Multi-dimensional and multi-parameter characterization method and device for heated rock mass in shale oil in-situ conversion stage

Abstract

The present invention discloses a multi-dimensional and multi-parameter characterization method and device for the heated rock mass of the in-situ conversion section of shale oil, including obtaining binary lithologic data of the organic-rich shale development section drilled in the study area, identifying the pseudo-in-situ conversion section according to the set upper limit of the proportion of non-organic-rich shale in the in-situ conversion section; dividing the pseudo-in-situ conversion section into at least one heated rock mass according to the binary lithologic and TOC distribution characteristics; identifying a single layer of non-organic-rich shale in the heated rock mass, and identifying it as an interlayer if its thickness is greater than the lower limit of the single layer thickness as an interlayer of the pseudo-in-situ conversion section; establishing a grid diagram of the drilled wells, and completing the spatial distribution study of the heated rock mass and the interlayer bodies therein in each well section based on the recognition of the single well. This method can combine the binary lithologic data with the organic matter abundance to finely divide the heated rock mass; identify the interlayer in the heated rock mass by the intuitive and easily obtainable lower limit of the interlayer thickness, and ultimately realize the spatial distribution study of the heated rock mass and the interlayer bodies therein.

Description

Technical Field

[0001] The present invention relates to the technical field of geophysics and shale oil development, and in particular to a multi-dimensional and multi-parameter characterization method and device for a heated rock mass in an in-situ conversion section of shale oil. Background Art

[0002] In the development of conventional oil and gas reservoirs, a series of methods and techniques, such as geological modeling and reservoir modeling, have been developed to precisely characterize the characteristics of target rock masses and their associated fluids to improve oil and gas recovery and development efficiency. However, because the development targets and methods differ from conventional and other unconventional oil and gas resources, existing geological body characterization techniques are not well suited for the detailed characterization of parameters in shale rock masses subjected to in-situ heating, a key development target for shale oil in-situ conversion. Existing evaluation and characterization of shale oil in-situ conversion development targets primarily focuses on favorable and sweet spots (Yang Zhi, Zou Caineng, Fu Jinhua, et al. Evaluation of Continental Shale Selection Based on In-situ Conversion / Upgrading Technology: A Case Study of the 7th Member of the Yanchang Formation, Triassic, Ordos Basin, 2017; Patent Grant No. CN 109113730 B). Vertically, five criteria for defining heating zones are proposed (Zhao Wenzhi, Hu Suyun, Hou Lianhua. The Connotation and Strategic Position of Underground In-situ Conversion of Shale Oil, 2018). However, during the in-situ conversion and development phase of shale oil, the research results and evaluation methods for favorable and sweet spots are too large-scale to be applied to the detailed characterization of specific heated rock masses; there is a basis for determining the vertical heating section, but there is a lack of operational methods and processes.

[0003] The detailed characterization and characterization of heated rock mass characteristics are crucial for optimal heating section selection, reserve and production estimation, well pattern design, development method optimization, and oil production engineering design during the in-situ conversion and development of shale oil. Therefore, it is necessary to establish a detailed characterization method for heated rock mass characteristics that is applicable to the specific characteristics of in-situ shale oil conversion technology. Summary of the Invention

[0004] In order to at least partially solve the technical problems existing in the prior art, the inventors have made the present invention. Through specific implementation methods, they provide a multi-dimensional and multi-parameter characterization method and device for the heated rock mass in the in-situ conversion section of shale oil. The binary lithological data and organic matter abundance are combined to finely divide the heated rock mass; the interlayers in the heated rock mass are identified through the intuitive and easy-to-obtain lower limit value of the interlayer thickness, and finally the spatial distribution study of the heated rock mass and the interlayer bodies therein is realized.

[0005] In a first aspect, an embodiment of the present invention provides a multi-dimensional and multi-parameter characterization method for a heated rock mass in an in-situ conversion stage of shale oil, comprising:

[0006] Obtaining binary lithologic data of organic-rich shale development sections developed in target layers of wells drilled in the study area, wherein the binary lithologic data includes organic-rich shale and non-organic-rich shale;

[0007] identifying at least one pseudo-in-situ conversion section within the organic-rich shale development section based on a set upper limit for the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithologic data, and dividing the pseudo-in-situ conversion section into at least one heated rock mass based on the distribution characteristics of the binary lithologic properties and TOC distribution characteristics;

[0008] Identifying a non-organic-rich shale single layer in the heated rock mass, and identifying the non-organic-rich shale single layer as an interlayer if the thickness of the non-organic-rich shale single layer is greater than a lower limit of the thickness of the single layer for being an interlayer in the simulated in-situ conversion section, wherein the lower limit of the thickness of the single layer is predetermined based on an average hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and a plurality of data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value;

[0009] A well-connected grid diagram of the drilled wells is established, and based on the identification results of the heated rock mass and interlayer of a single well, a spatial distribution study of the heated rock mass and the interlayer in each well-connected section in the well-connected grid diagram is completed.

[0010] In a second aspect, an embodiment of the present invention provides a multi-dimensional and multi-parameter characterization device for heated rock mass in an in-situ conversion section of shale oil, the device comprising a binary lithologic data acquisition module, a heated rock mass division module, an interlayer identification module, a heated rock mass distribution feature research module, and an interlayer single layer thickness lower limit determination module;

[0011] The binary lithologic data acquisition module is used to acquire binary lithologic data of the organic-rich shale development section developed in the target layer of the well drilled in the study block, wherein the binary lithologic data includes organic-rich shale and non-organic-rich shale;

[0012] The heated rock mass division module is configured to identify at least one pseudo-in-situ conversion section within the organic-rich shale development section based on a set upper limit of the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithologic data, and to divide the pseudo-in-situ conversion section into at least one heated rock mass based on the distribution characteristics of the binary lithologic properties and the TOC distribution characteristics;

[0013] The interlayer identification module is configured to identify a non-organic-rich shale single layer in the heated rock mass. If the thickness of the non-organic-rich shale single layer is greater than a lower limit of the thickness of the single layer used as an interlayer in the simulated in-situ conversion section, the non-organic-rich shale single layer is identified as an interlayer. The lower limit of the thickness of the single layer is predetermined by the interlayer single layer thickness lower limit determination module based on an average hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and a plurality of data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value.

[0014] The heated rock mass distribution feature research module is used to establish a well-connected grid diagram of the drilled wells, and based on the heated rock mass and interlayer identification results of a single well, complete the spatial distribution research of the heated rock mass and the interlayer in each well-connected section in the well-connected grid diagram.

[0015] In a third aspect, an embodiment of the present invention provides a computer storage medium, in which computer executable instructions are stored. When the computer executable instructions are executed by a processor, the multi-dimensional and multi-parameter characterization method of the heated rock mass in the in-situ conversion section of shale oil is implemented.

[0016] In a fourth aspect, an embodiment of the present disclosure provides a server comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the multi-dimensional and multi-parameter characterization method for heated rock mass in the in-situ conversion section of shale oil is implemented.

[0017] The beneficial effects of the above technical solutions provided by the embodiments of the present invention include at least:

[0018] (1) The multi-dimensional and multi-parameter characterization method for the heated rock mass in the in-situ conversion section of shale oil provided by the embodiment of the present invention, based on the binary lithologic data of the organic-rich shale development section, identifies the pseudo-in-situ conversion section according to the upper limit of the proportion of non-organic-rich shale in the in-situ conversion section, obtains the binary lithologic data of the organic-rich shale development section, and further subdivides the heated rock mass in the pseudo-in-situ conversion section based on the binary lithologic differences and TOC differences; identifies the interlayers in the heated rock mass by the intuitive and easily obtainable lower limit of the interlayer thickness; and completes the spatial distribution study of the heated rock mass and the interlayer bodies therein in each well-connected section in the well-connected grid diagram based on the understanding of the single well. From single well to well-connected wells to well-connected grid diagrams, from the characterization of the heated rock mass to the tracking of the interlayer bodies therein, a multi-dimensional and multi-parameter characterization of the heated rock mass is achieved, providing an important reference for the design of subsequent development plans.

[0019] (2) The multi-dimensional and multi-parameter characterization method for the heated rock mass in the in-situ conversion section of shale oil provided in the embodiment of the present invention, based on the binary lithologic data of the organic-rich shale development section, identifies the pseudo-in-situ conversion section according to the upper limit of the proportion of non-organic-rich shale in the in-situ conversion section; further subdivides the heated rock mass in the pseudo-in-situ conversion section based on the binary lithologic differences and TOC differences, making it possible to adopt different well layout methods, heating schemes, and subsequent oil and gas development plans for heated rock masses with different geological and geochemical conditions, providing an important geological evaluation method for the large-scale and efficient development of shale oil in-situ conversion. In other words, the field significance of this achievement lies in making it possible to design refined and differentiated in-situ conversion development plans.

[0020] (3) The multi-dimensional and multi-parameter characterization method for the heated rock mass of the in-situ conversion section of shale oil provided in the embodiment of the present invention predetermines the lower limit of the thickness of the non-organic-rich shale single layer as the interlayer of the pseudo-in-situ conversion section based on the average value of the hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and multiple data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value; if the thickness of the non-organic-rich shale single layer is determined to be greater than the lower limit of the thickness of the interlayer, it is determined to be an interlayer. First, this method is targeted at the specific application scenario of the organic-rich shale development section, breaking the limitation of the traditional method of relying solely on lithology to identify interlayers, and is more suitable for the geological evaluation and related research of shale oil in-situ conversion; in addition, this method converts the lower limit of the hydrocarbon generation potential of the interlayer into a more intuitive and easier to obtain lower limit of the interlayer thickness, reducing the requirements for data, and only lithology data is needed to realize the identification of interlayers in the pseudo-in-situ conversion section of shale oil. The direct reason why the lower limit of the hydrocarbon generation potential of the interlayer can be converted into the lower limit of the interlayer thickness in this way is that the interlayer thickness has a relatively significant statistical relationship with the hydrocarbon generation potential of the interlayer; and the fundamental reason is that the enrichment of organic matter requires an extremely low sedimentation rate, and the smaller the thickness of the single interlayer, the faster the sedimentation rate, the more difficult it is to enrich organic matter, and ultimately the worse the hydrocarbon generation potential.

[0021] (4) The multi-dimensional and multi-parameter characterization method for the heated rock mass of the in-situ conversion section of shale oil provided in the embodiment of the present invention determines the data on which the lower limit of the single-layer thickness of the non-organic-rich shale as the interlayer of the pseudo-in-situ conversion section depends, which is the average value of the hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and multiple data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value, which are obtained in the following way: according to the binary lithologic data of the continuous coring section in the shale layer and the upper limit of the proportion of non-organic-rich shale in the in-situ conversion section, the pseudo-in-situ conversion section is identified from the coring section; according to the sedimentary cycle, the pseudo-in-situ conversion section is identified from the coring section. The identified pseudo-in situ conversion section was divided into multiple units. The type of each unit was determined by its thickness ratio relative to the pseudo-in situ conversion section, and at least one unit of each type was selected. A millimeter-level lithologic description was performed on the selected units. Based on the description results, the units were divided into multiple organic-rich shale layers and non-organic-rich shale layers. Rock samples were cut from the layers and their hydrocarbon generation potentials were determined through pyrolysis testing. The average hydrocarbon generation potential of the organic-rich shale layers was statistically calculated, along with multiple data pairs containing the thickness and hydrocarbon generation potential of the non-organic-rich shale layers. Taking into account the geological characteristics of continental shale formations, such as rapid lithologic changes and thin single-layer thickness, the lithologic combination classification, multi-level core characterization, and multi-scale sampling interval screening significantly reduced the workload while ensuring the lithologic representativeness and high sampling accuracy of the collected samples.

[0022] (5) The multi-dimensional and multi-parameter characterization method for the heated rock mass in the in-situ conversion section of shale oil provided by the embodiment of the present invention is aimed at the specific scenario of lithologic identification of thin interlayers in the organic-rich shale development section. It abandons the universal pursuit of conventional well logging lithologic interpretation to interpret and characterize various lithologies developed in the study area separately, and limits the lithologic interpretation objects to two types: organic-rich shale and non-organic-rich shale. It reduces the multi-solution of well logging lithologic interpretation and improves the interpretation accuracy; at the same time, it reduces the amount of calculation and improves the recognition speed of batch interpretation of multiple wells.

[0023] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purposes and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0024] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0026] Figure 1 This is a flow chart of a method for determining the lower limit of the thickness of a single layer of non-organic-rich shale as an interlayer in Example 1 of the present invention;

[0027] Figure 2 This is a flow chart of a method for establishing a lithology identification model for an organic-rich shale development section based on lithology binarization in Example 2 of the present invention;

[0028] Figure 3 This is a flow chart of a multi-dimensional and multi-parameter characterization method for a heated rock mass in an in-situ conversion stage of shale oil in Example 3 of the present invention;

[0029] Figure 4 This is a flow chart of a method for simultaneous screening of multiple wells, multiple curves, and multiple lithologic sensitivity curves in a fourth embodiment of the present invention;

[0030] Figure 5 This is an example diagram of the simultaneous comparison and screening of sensitivity curves of all sample points and the lithologic distribution vein lines in the fourth embodiment of the present invention;

[0031] Figure 6 This is a flow chart of a method for determining the sealing thickness of a complex lithologic layer based on a simplified lithologic combination in Example 5 of the present invention;

[0032] Figure 7 This is a comprehensive histogram of the core wells at both ends of the long axis of the rock mass to be heated in Example 6 of the present invention;

[0033] Figure 8 for Figure 7 Example of one-dimensional single-well division of the heating formation unit of the core well 1;

[0034] Figure 9 This is the two-dimensional well connection characterization of the north-south heated rock mass in the shale oil in-situ conversion development area in Example 6 of the present invention;

[0035] Figure 10 This is the characterization of the thickness of the heated rock mass in the shale oil in-situ conversion development block in Example 6 of the present invention;

[0036] Figure 11 This is the case of characterizing the thickness of the heated rock mass top in the shale oil in-situ conversion development block in Example 6 of the present invention;

[0037] Figure 12 This is the three-dimensional grid diagram representation of the heated rock mass in the shale oil in-situ conversion development area in Example 6 of the present invention;

[0038] Figure 13 This is a schematic structural diagram of a multi-dimensional and multi-parameter characterization device for heating rock mass in the in-situ conversion stage of shale oil in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0040] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0041] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the invention belongs. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of any conflict with any incorporated document, the content of this specification shall prevail.

[0042] In the embodiment of the present application, the TOC lower limit of organic-rich shale is used as a standard to classify organic-rich shale and non-organic-rich shale. Specifically, the lithology of rocks with TOC greater than the lower limit is defined as organic-rich shale; the lithology of rocks with TOC not greater than the lower limit is defined as non-organic-rich shale.

[0043] The lower limit of TOC of organic-rich shale is flexibly set according to the actual geological conditions of the study area, and can usually be set to 2%, 3% or 5%. Optionally, it can also be set to other values.

[0044] Example 1

[0045] The first embodiment of the present invention provides a method for determining the lower limit of the thickness of a single layer of non-organic-rich shale as an interlayer of a pseudo-in-situ conversion section in a shale layer, specifically determining the lower limit of the thickness of a non-organic-rich shale interlayer identified from a pseudo-in-situ conversion section in a shale layer, referring to Figure 1 As shown, the following steps are included:

[0046] Step S11: Based on the binary lithologic data of the cored section of the target layer of the sample well and the upper limit of the proportion of non-organic-rich shale in the in-situ conversion section, identify the pseudo-in-situ conversion section from the cored section, divide the identified pseudo-in-situ conversion section into multiple units, determine the type of each unit according to the thickness ratio of the pseudo-in-situ conversion section, and select at least one unit from each type of unit.

[0047] First, typical dissected wells are selected to identify interlayers with low hydrocarbon generation potential. Generally, typical dissected wells must meet the following requirements:

[0048] (1) The dissecting well must be located within the shale oil in-situ conversion development block, or at least adjacent to the development block;

[0049] (2) at least one well;

[0050] (3) There is a continuous coring section in the shale oil in-situ conversion section where the shale is to be heated.

[0051] Binary lithologic data of the coring section, including organic-rich shale and non-organic-rich shale, can be obtained from core description data, thin section identification data, and TOC detection data of the coring section of the target layer of the sample well. The acquisition process includes the following description in Example 2.

[0052] Here, the binary lithology data of the core section needs to be centimeter-level lithology data.

[0053] The thickness of the non-organic-rich shale in the simulated in-situ conversion section identified from the coring section is less than the set upper limit of the non-organic-rich shale ratio in the in-situ conversion section.

[0054] The upper limit of the proportion of non-organic-rich shale in the in-situ conversion section can usually be set to 20%. Optionally, it can also be set to other values ​​according to relevant regulations or actual research needs.

[0055] In some embodiments, the quasi-in-situ conversion section can be divided into multiple units according to the sedimentation cycle, that is, divided into multiple sedimentation cycles, with a single sedimentation cycle as a unit.

[0056] Each unit is divided into one of the following types according to its thickness ratio to the proposed in-situ conversion section:

[0057] (1) The thickness ratio of the proposed in-situ conversion section is less than 1%,

[0058] (2) The thickness ratio of the proposed in-situ conversion section is not less than 1% and not more than 5%,

[0059] (3) The thickness ratio of the proposed in-situ conversion section is greater than 5% and not greater than 10%,

[0060] (4) The thickness ratio of the in-situ conversion section is greater than 10%.

[0061] The basis for this classification is that the thickness of a single sedimentary cycle is affected by the comprehensive influence of the sedimentary paleoenvironment, which will affect the organic matter abundance of the lithologic combination section.

[0062] The same number of units can be screened from each type of unit. One typical unit can be screened from each type of unit. If the research time and conditions permit, multiple units can also be screened.

[0063] Step S12: Perform millimeter-level binary lithologic description on the selected units. Based on the description results, divide the units into multiple organic-rich shale monolayers and non-organic-rich shale monolayers. Cut rock samples from the monolayers and determine the hydrocarbon generation potential of the rock samples through pyrolysis testing.

[0064] Based on the millimeter-level binary lithologic description of the selected units, the following steps are performed:

[0065] (1) Using wire cutting technology, cut each lithologic layer of each unit (sampling layer) along the lithologic layer plane, and prepare an independent flaky rock sample for each lithologic layer. The thickness of the rock sample is the thickness of the single layer, and the volume of a single rock sample must meet the mass required for rock pyrolysis (preferably, not less than 5 grams); (2) Conduct rock pyrolysis testing on each rock sample; (3) Calculate the sum of free hydrocarbons (S1) (unit: mg / g, the amount of free hydrocarbons in the rock per unit mass) and pyrolysis hydrocarbons (S2) (unit: mg / g, the amount of hydrocarbons generated after pyrolysis of the rock per unit mass) of each pyrolysis rock sample as the hydrocarbon generation potential value of the rock sample.

[0066] Step S13: Statistically obtain an average value of the hydrocarbon generation potential value of a single layer of organic-rich shale and a plurality of data pairs including the thickness of a single layer of non-organic-rich shale and its hydrocarbon generation potential value.

[0067] The data used to determine the lower limit of the thickness of a non-organic-rich shale monolayer as an interlayer of a pseudo-in situ conversion section are the average hydrocarbon generation potential of the organic-rich shale monolayer within the shale layer and multiple data pairs including the thickness of the non-organic-rich shale monolayer and its hydrocarbon generation potential. The data are obtained in the following manner: based on the binary lithologic data of consecutive coring sections within the shale layer and the upper limit of the proportion of non-organic-rich shale in the in situ conversion section, the pseudo-in situ conversion section is identified from the coring section; the identified pseudo-in situ conversion section is divided into multiple units according to the sedimentary cycle, the type of each unit is determined according to the thickness ratio of each unit to the pseudo-in situ conversion section, and at least one unit of each type is selected; the selected units are subjected to millimeter-level lithologic description, and based on the description results, the units are divided into multiple organic-rich shale monolayers and non-organic-rich shale monolayers; rock samples are cut from the monolayers and the hydrocarbon generation potential of the rock samples is determined by pyrolysis testing; and the average hydrocarbon generation potential of the organic-rich shale monolayer and multiple data pairs including the thickness of the non-organic-rich shale monolayer and its hydrocarbon generation potential are statistically obtained. Taking full account of the geological characteristics of the continental shale formations, such as rapid lithologic changes and thin single-layer thickness, the basic workload was greatly reduced through lithologic combination division, multi-level core detailed description, and multi-scale sampling layer screening, while taking into account the lithologic representativeness and high sampling accuracy of the collected samples.

[0068] Step S14: Based on each data pair, a sample point is obtained, which includes the ratio of the thickness of the non-organic-rich shale single layer and the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the organic-rich shale single layer.

[0069] Step S15: Project the sample points into a coordinate system and obtain a trend line by fitting. Based on the trend line, determine the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the organic-rich shale single layer as the thickness of the non-organic-rich shale single layer corresponding to the set ratio. This thickness is determined as the lower limit of the single layer thickness of the non-organic-rich shale single layer as the interlayer of the simulated in-situ conversion section.

[0070] The coordinate system uses the thickness of a non-organic-rich shale single layer and the ratio of the hydrocarbon generation potential value of a non-organic-rich shale single layer to the average hydrocarbon generation potential value of a shale single layer (hydrocarbon generation potential value of a non-organic-rich shale single layer / average hydrocarbon generation potential value of a shale single layer) as the coordinate axes.

[0071] The above-mentioned set ratio is usually 38% to 42%; preferably, it is 40%.

[0072] Taking the set ratio of 40% as an example, 40% of the average hydrocarbon generation potential value of all organic-rich shale single layers in the pseudo-in situ conversion section is used as the lower limit of the hydrocarbon generation potential of the interlayer of the pseudo-in situ conversion section; then, through the above-mentioned thickness conversion, the lower limit of the single layer thickness of the non-organic-rich shale single layer as the interlayer of the pseudo-in situ conversion section is obtained.

[0073] The direct reason why Example 1 of the present application can convert the lower limit value of the hydrocarbon generation potential of the interlayer into the lower limit value of the thickness of the interlayer is that the thickness of the interlayer has a relatively significant statistical relationship with the hydrocarbon generation potential of the interlayer; and the fundamental reason is that the enrichment of organic matter requires an extremely low deposition rate, and the smaller the thickness of the interlayer single layer, the faster the deposition rate, the more difficult it is to enrich the organic matter, and ultimately the worse the hydrocarbon generation potential.

[0074] Example 2

[0075] The second embodiment of the present invention provides a method for establishing a lithology identification model for an organic-rich shale development section based on lithology binarization. Figure 2 As shown, the following steps are included:

[0076] Step S21: Determine the lower limit of the GR value of the organic-rich shale based on the binary lithologic data of the core section of the target layer of the sample well.

[0077] Wells cored in the target layer of the study area are selected as sample wells. Optionally, the selected wells can be divided into sample wells and verification wells. The relevant data of the verification wells do not participate in the training of the model and are only used for the later verification of the model.

[0078] Specifically, the binary lithologic data of the core section, including organic-rich shale and non-organic-rich shale (i.e., interlayer), is obtained by the following steps:

[0079] (1) Based on the thin section identification data of the core section of the target layer of the sample well, the lithologic description data in the core description data is corrected to obtain preliminary lithologic data, which includes mud shale.

[0080] The lithologic descriptions in core data are merely empirical descriptions of the cores made by geologists based on visual observation. Due to the limitations of visual observation and subjective factors, the accuracy of these lithologic descriptions requires further refinement. Thin section identification data can accurately assign lithologic names, but thin section identification data is limited in sampling. Therefore, preliminary lithologic data is obtained based on the lithologic descriptions in the core data and verified with thin section identification data.

[0081] The preliminary description data obtained may include clastic rocks such as shale, coarse sandstone, medium sandstone, fine sandstone and siltstone, and may also include carbonate rocks or other rock types.

[0082] (2) Based on the TOC detection data, the mud shale with a TOC value greater than the preset lower limit of TOC for organic-rich shale in the preliminary lithologic data is determined as organic-rich shale, and the binary lithologic data of the coring section is obtained.

[0083] Thin section identification data can be used to accurately determine lithologic names at the millimeter level. However, thin section identification data cannot distinguish between organic-rich and non-organic-rich shales. In this case, TOC values ​​must be referenced to define shales with TOC values ​​no greater than the lower limit of the TOC of organic-rich shales, as well as other lithologies other than shales, as non-organic-rich shales.

[0084] It can be seen that the organic-rich shale in this embodiment is defined based on the TOC lower limit of organic-rich shale. Shale that meets this lower limit is organic-rich shale; the organic-rich shale development section refers to a rock formation composed of organic-rich shale and its interlayers.

[0085] The lower limit of TOC of organic-rich shale is flexibly set according to the actual geological conditions of the study area, and can usually be set to 2%, 3% or 5%. Optionally, it can also be set to other values.

[0086] Mud shales with TOC values ​​not greater than the lower limit of TOC of organic-rich shales, as well as other lithologies other than mud shales, are identified as non-organic-rich shales.

[0087] Determining the lower limit of the GR value of organic-rich shale can include extracting the lithology and GR values ​​of sampling points with thin section identification data and TOC test data based on lithology data and GR curves of sample wells; and statistically obtaining the lower limit of the GR value of organic-rich shale based on the lithology and GR values ​​of multiple sampling points.

[0088] Since the interlayer identification in this embodiment is based on the well logging curve, the well logging curve of the sample well must first be standardized; after obtaining the preliminary lithologic data or binary lithologic data of the coring section, the standardized well logging curve is depth-relocated.

[0089] The GR values ​​of the above sampling points are extracted from the GR curve after standardization and depth resetting.

[0090] Step S22: taking the binary lithologic data of the coring section and the curve section of the selected sensitivity curve as a sample, and establishing a sample set.

[0091] In some embodiments, after obtaining the binary lithologic data for the coring section, the method further includes screening sensitivity curves for organic-rich shale and non-organic-rich shale from all types of well logging curves in the sample wells. The specific screening method can adopt the method described in Example 4 below, or other conventional methods can be used.

[0092] Step S23: Use the sample set to train the selected neural network model, establish a lithology recognition model, and input the GR value lower limit into the lithology recognition model.

[0093] Example 3

[0094] The third embodiment of the present invention provides a multi-dimensional and multi-parameter characterization of the heated rock mass in the in-situ conversion stage of shale oil. Figure 3 As shown, the following steps are included:

[0095] Step S31: Obtain binary lithologic data of organic-rich shale development sections developed in target layers drilled in the study area.

[0096] Binary lithologic data include organic-rich shales and non-organic-rich shales.

[0097] If a well has been drilled and coring has been conducted in the target layer, and the coring section passes through the organic-rich shale development section of the target layer, binary lithologic data of the organic-rich shale development section can be obtained based on the core description data, thin section identification data, and TOC test data. The specific method is described in Example 2.

[0098] If a well has been drilled and coring is done in the target layer, but the coring section does not pass through the organic-rich shale development section of the target layer and only part of the coring is done, the binary lithologic data of the coring section shall be used as the standard. The binary lithologic data of the entire organic-rich shale development section shall be obtained by combining the uncored section with the logging interpretation results.

[0099] For wells drilled without coring, the binary lithologic data of the organic-rich shale development intervals are obtained by the following method:

[0100] The sensitivity curve of the drilled well is input into the lithologic identification model, and the binary lithologic data of the organic-rich shale development section is obtained according to the output of the model. The lithologic identification model is pre-established by the method in the above-mentioned second embodiment.

[0101] The lithologic identification model works by initially locating organic-rich shale development intervals based on the lower limit of the GR value of organic-rich shale and the GR curves of existing wells. Based on the neural network learning results of the corresponding sensitive curve segments of the organic-rich shale development intervals, the binary lithologic data is determined and output.

[0102] That is, the lower limit of the GR value of organic-rich shale is first used to roughly locate the organic-rich shale development section, and then the lithology identification model is used to perform fine and high-resolution binary lithology prediction for the organic-rich shale development section.

[0103] In some embodiments, before inputting the sensitivity curves of the drilled wells into the lithologic identification model, the process also includes using rock logging data to remove high GR outliers from the sensitivity curves of the drilled wells, such as those in non-organic-rich shales. For example, interference from high GR values ​​in organic-rich shales caused by specific high GR rocks, such as high-uranium sandstone, can be removed.

[0104] Step S32: identifying at least one pseudo-in-situ conversion section within the organic-rich shale development section according to the set upper limit of the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithologic data.

[0105] That is, the identified pseudo-in-situ conversion section satisfies the requirement that the thickness of the non-organic-rich shale layer is less than the upper limit of the non-organic-rich shale ratio in the in-situ conversion section.

[0106] The upper limit of the proportion of non-organic-rich shale in the in-situ conversion section can usually be set to 20%. Optionally, it can also be set to other values ​​according to relevant regulations or actual research needs.

[0107] Step S33: Divide the quasi-in-situ conversion section into at least one heated rock mass according to the distribution characteristics of the binary lithology and the TOC distribution characteristics.

[0108] Alternatively, a histogram of the binary lithologic profile and TOC profile of the organic-rich shale development section may be established.

[0109] Furthermore, if there is coring data for the organic-rich shale development section of the target well, the lithologic profile is established based on the binary lithologic description data of the coring data; if the binary lithologic description data in the coring data is incomplete, the lithologic data is supplemented in combination with the model output results to establish a binary lithologic profile.

[0110] The TOC profile can be established by using the measured TOC values ​​if there are continuous TOC values ​​(sampling interval is not greater than 0.5 meters) in the organic-rich shale development section of the target well. If there are no or only partial measured TOC values ​​in the organic-rich shale development section of the target well, the measured TOC values ​​are used first, and the interpreted TOC values ​​of the TOC interpretation model are used to supplement the measured TOC data in the remaining sections to establish the TOC profile.

[0111] Specifically, the division of the heated rock mass in the proposed in-situ conversion stage is based on the following principles:

[0112] The TOC difference between the heated rock mass and the adjacent heated rock mass satisfies a first set difference, and / or the lithology combination difference between the heated rock mass and the adjacent heated rock mass satisfies a second set difference.

[0113] Furthermore, the first set difference includes the overall TOC value difference and / or the overall TOC curve morphology difference; the second set difference includes the number of non-organic-rich shale layers and / or the thickness of non-organic-rich shale layers.

[0114] There are three situations in which a shale oil in-situ conversion heated rock mass is different from an adjacent heated rock mass. Situation 1: The heated rock mass and its adjacent heated rock mass have significantly different TOC value curve characteristics, such as overall TOC value differences or overall TOC value curve morphology differences. The specific differences need to be determined in combination with actual conditions in different embodiments. Situation 2: The heated rock mass and its adjacent heated rock mass do not have significantly different TOC value curve characteristics, but have significantly different lithologic combinations, such as the number of interlayers or the thickness of a single interlayer. The specific differences need to be determined in combination with actual conditions in different embodiments. Situation 3: The heated rock mass and its adjacent heated rock mass have both TOC value curve characteristic differences and lithologic combination differences.

[0115] Step S34: Identify a non-organic-rich shale single layer in the heated rock mass. If the thickness of the non-organic-rich shale single layer is greater than the lower limit of the single layer thickness as an interlayer in the simulated in-situ conversion section, identify the non-organic-rich shale single layer as an interlayer.

[0116] The lower limit of the single layer thickness is predetermined based on the average hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and multiple data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value. The specific determination method is described in Example 1.

[0117] After all the wells drilled in the study area (wells that have penetrated the target layer) have completed the above steps S31 to S34, step S35 is executed.

[0118] Step S35: Establish a well-connected grid diagram of the drilled wells, and complete the spatial distribution study of the heated rock mass and the interlayer in each well-connected section in the well-connected grid diagram based on the identification results of the heated rock mass and interlayer of the single well.

[0119] The well grid diagram covers all drilled wells that penetrate the target layer.

[0120] The third embodiment of the present application provides a multi-dimensional, multi-parameter characterization method for heated rock masses in the in-situ conversion phase of shale oil. The working principle of the binary lithologic interpretation method is as follows: Based on the fact that organic-rich shale forms in a reducing environment that facilitates uranium precipitation, resulting in high uranium and high natural gamma ray characteristics that distinguish it from other lithologies, the method utilizes natural gamma ray combined with conventional rock logging to eliminate interference from other non-shale, high-GR rocks (such as sandstone-type uranium deposits) and identify the vertical distribution of high-GR organic-rich shale development segments. Within the identified organic-rich shale development segments, the correlation between various conventional well logging curves and the organic-rich shale is automatically calculated, and the curve with the best correlation is directly selected as the input curve. A neural network method is then used to automatically establish a lithologic identification model for organic-rich shale and non-organic-rich shale. The lithologic identification model is continuously and iteratively verified in calibration wells to ensure that the interpretation results are consistent with the actual results. Ultimately, the front-end inputs various conventional well logging curves, and the terminal automatically generates a high-precision lithologic profile containing both organic-rich and non-organic-rich shale.

[0121] The multi-dimensional and multi-parameter characterization method for the heated rock mass in the in-situ conversion section of shale oil provided in Example 3 of the present invention, for a single well, based on the binary lithologic data obtained for the organic-rich shale development section, identifies the pseudo-in-situ conversion section according to the upper limit of the proportion of non-organic-rich shale in the in-situ conversion section; further subdivides the heated rock mass in the pseudo-in-situ conversion section based on binary lithologic differences and TOC differences; identifies interlayers within the heated rock mass using the intuitively accessible lower limit of interlayer thickness; and, based on the knowledge of a single well, completes the spatial distribution study of the heated rock mass and its interlayers in each well-connected section in the well-connected grid diagram. From single wells to well-connected grid diagrams, and from characterizing the heated rock mass to tracking its interlayers, a multi-dimensional and multi-parameter characterization of the heated rock mass is achieved, providing an important reference for the design of subsequent development plans.

[0122] The multi-dimensional, multi-parameter characterization method for heated rock masses in the in-situ conversion zone of shale oil, provided in Example 3 of the present invention, obtains binary lithologic data for organic-rich shale development zones and, based on the upper limit of the proportion of non-organic-rich shale in these zones, identifies pseudo-in-situ conversion zones. Within these pseudo-in-situ conversion zones, the heated rock masses are further subdivided based on binary lithologic and TOC differences. This enables the adoption of different well placement methods, heating schemes, and subsequent oil and gas development plans for heated rock masses with varying geological and geochemical conditions, providing an important geological evaluation tool for the efficient and large-scale development of in-situ conversion of shale oil. The practical significance of this achievement lies in enabling the refined and differentiated design of in-situ conversion development plans.

[0123] The multi-dimensional and multi-parameter characterization method for the heated rock mass of the in-situ conversion section of shale oil provided in Example 3 of the present invention predetermines the lower limit of the single-layer thickness of the non-organic-rich shale as an interlayer in the situ conversion section based on the average value of the hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and multiple data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value; if the thickness of the non-organic-rich shale single layer is determined to be greater than the lower limit of the single-layer thickness as an interlayer, it is determined to be an interlayer. First, this method is targeted at the specific application scenario of the organic-rich shale development section, breaking the limitation of the traditional reliance on lithology to identify interlayers, and is more suitable for geological evaluation and related research on shale oil in-situ conversion; in addition, this method converts the lower limit of the hydrocarbon generation potential of the interlayer into a more intuitive and easier to obtain lower limit of the interlayer thickness, reducing the requirements for data, and only lithology data is needed to realize the identification of interlayers in the shale oil in-situ conversion section. The direct reason why the lower limit of the hydrocarbon generation potential of the interlayer can be converted into the lower limit of the interlayer thickness in this way is that the interlayer thickness has a relatively significant statistical relationship with the hydrocarbon generation potential of the interlayer; and the fundamental reason is that the enrichment of organic matter requires an extremely low sedimentation rate, and the smaller the thickness of the single interlayer, the faster the sedimentation rate, the more difficult it is to enrich organic matter, and ultimately the worse the hydrocarbon generation potential.

[0124] The multi-dimensional and multi-parameter characterization method for the heated rock mass in the in-situ conversion section of shale oil provided in Example 3 of the present invention is aimed at the specific scenario of lithologic identification of thin interlayers in the organic-rich shale development section. It abandons the universal pursuit of conventional well logging lithologic interpretation to interpret and characterize various lithologies developed in the study area separately, and limits the lithologic interpretation objects to two types: organic-rich shale and interlayers (non-organic-rich shale). It reduces the multi-solution of well logging lithologic interpretation and improves the interpretation accuracy; at the same time, it reduces the amount of calculation and improves the recognition speed of batch interpretation of multiple wells.

[0125] The multi-dimensional, multi-parameter characterization method for heated rock mass in the in-situ conversion stage of shale oil, provided in Example 3 of the present invention, requires only core data from sample wells during the lithologic identification model establishment phase. Once the model is complete, conventional well logging curves are sufficient for high-precision characterization of the binary lithologic properties of organic-rich shale. This significantly reduces the requirements for data quality while ensuring interpretation accuracy.

[0126] In some embodiments, it may also include, for each heated rock mass, counting the heated rock mass thickness, interlayer thickness and interlayer thickness ratio of a single well, and drawing a heated rock mass thickness plane map, an interlayer thickness plane map and an interlayer thickness ratio plane map by interpolation method.

[0127] Example 4

[0128] The fourth embodiment of the present invention provides a method for synchronous screening of multiple wells, multiple curves and multiple lithologic sensitivity curves. Figure 4 As shown, the following steps are included:

[0129] Step S41: Acquire multiple sample points of the target layer.

[0130] Each sample point includes the binary lithology type and the value of each curve to be screened.

[0131] The curve to be screened may be depth-calibrated based on the binary lithologic data of the sample well in the second embodiment, and a matching relationship between the lithologic data and the curve to be screened in depth may be established to obtain a well logging lithologic calibration chart.

[0132] The extraction of sample points can be based on the sampling points of the logging curve. For example, if the logging curve is sampled every 0.125m, the sample points are also sampled every 0.125m, or the samples are sampled after thinning.

[0133] The sampling method of the above-mentioned sample points is different from the traditional method of using rock sample collection points as calibration points. This improvement will greatly improve the richness and vertical continuity of sample data.

[0134] Multiple wells with continuous core samples in the target layer of the study area can be identified as sample wells. The sample wells are representative and comprehensive, thereby greatly reducing the impact of geological heterogeneity on the accuracy of lithologic sensitivity curve screening.

[0135] Step S42: Project each sample point into a coordinate system containing multiple parallel axes, where each axis corresponds to a different curve to be screened.

[0136] Based on the well logging lithology calibration chart, the numerical distribution range of each curve to be screened is statistically analyzed.

[0137] Establish a coordinate system consisting of multiple parallel axes, with the axes aligned at both ends and their values ​​matching the corresponding numerical distribution range. This can be achieved by aligning the values ​​at both ends with the corresponding numerical distribution range, or by ensuring that the minimum value is less than the minimum value in the numerical distribution range, and the maximum value is greater than the maximum value in the numerical distribution range.

[0138] Taking the well logging curve GR as an example, if the numerical distribution range of GR in the target layer is 200 API to 500 API, the two end values ​​of the number axis corresponding to the well logging curve GR can be set to 200 API and 500 API respectively.

[0139] In some embodiments, the numerical values ​​of the axes in the established coordinate system change in the same direction.

[0140] Taking the example of each number axis being distributed vertically, the values ​​of each number axis gradually increase from top to bottom, or gradually decrease from top to bottom.

[0141] Step S43: Connect the projection points of the same sample point on different number axes to obtain a vein line.

[0142] Use line type or color to distinguish rock types.

[0143] Step S44: screening at least one type of lithologic sensitivity curve according to the distribution characteristics of the vein lines.

[0144] In some embodiments, the method may include screening at least one type of lithologic sensitivity curve based on the following knowledge, according to the distribution characteristics of the vein lines on the number axis:

[0145] The more convergent the vein lines of organic-rich shale on a certain axis, and the more distinct the difference between the vein lines of organic-rich shale and non-organic-rich shale, the more sensitive the corresponding screening curve to organic-rich shale is, and vice versa. Figure 5 shown.

[0146] The method for simultaneous screening of multi-well, multi-curve, and multi-lithologic sensitivity curves provided in the fourth embodiment of the present invention reduces the influence of human subjective factors in the sensitivity curve selection process and improves the objectivity of the selection results by converting the correlation between logging curves and lithology into a more intuitive line convergence and differentiation degree.

[0147] The method for synchronous screening of multi-well, multi-curve, and multi-lithologic sensitivity curves provided in the fourth embodiment of the present invention establishes a coordinate system including multiple parallel axes, each axis corresponding to a different curve to be screened, and draws vein lines corresponding to different sample points in the coordinate system. This enables synchronous comparison of curves of different types in the same coordinate system, improves the accuracy of sensitive curve selection, makes it less likely that sensitive curves will be missed, and greatly improves screening efficiency.

[0148] The method for synchronous screening of multiple wells, multiple curves, and multiple lithologic sensitivity curves provided in the fourth embodiment of the present invention connects the projection points of the same sample point on different number axes to obtain a vein line. One sample point corresponds to one vein line, and the possibility of two vein lines completely overlapping is very small, avoiding the situation of a large number of points overlapping caused by a simple point-casting method, so that the final lithologic distribution vein line map is more complete and representative.

[0149] In some embodiments, the multi-dimensional and multi-parameter characterization of the heated rock mass in the in-situ conversion section of shale oil can also characterize the lower limit of the sealing thickness of the overlying and underlying rock layers required for in-situ mining. The following Example 5 is illustrated by taking the determination of the lower limit of the sealing thickness of the overlying rock layer (a complex lithological layer of siltstone and mud shale layers) as an example. A similar method can be used to determine the lower limit of the sealing thickness of the underlying rock layer.

[0150] Example 5

[0151] The fifth embodiment of the present invention provides a method for determining the sealing thickness of a complex lithology layer based on a simplified lithology combination, referring to Figure 6 As shown, the following steps are included:

[0152] Step S61: Determine the vertical superposition relationship of the siltstone layer and the mud shale layer, and the total thickness of the siltstone layer and the total thickness of the mud shale layer according to the vertical distribution characteristics of the lithology of the overlying strata within a set range.

[0153] The complex lithologic layer is the overlying stratum of the shale reservoir, which is composed of interbedded siltstone and mud shale.

[0154] Empirical data indicates that the roof seal thickness during in-situ mining of shale reservoirs is typically within 300-400 centimeters. Therefore, the length (thickness) of the roof rock sample should be no less than 500 cm. Any thicker increases experimental difficulty and cost; any thinner will easily fall below the actual lower limit of the roof seal thickness, resulting in experimental failure (unable to measure the required in-situ roof seal thickness for shale). This means that the overlying stratum should be within a 500 cm thickness range, preferably within 500 cm from the location closest to the top of the shale reservoir upward.

[0155] The set range is divided into an upper and a lower part by an averaging method. If the cumulative thickness of the lower shale layer exceeds the first set ratio (for example, more than 60%), the superposition relationship is determined to be the shale layer at the bottom and the siltstone layer at the top; if the cumulative thickness of the lower shale layer is lower than the second set ratio (for example, lower than 40%), the superposition relationship is determined to be the shale layer at the top and the siltstone layer at the bottom; if the cumulative thickness of the lower shale layer is within the set ratio range (for example, 40% to 60%), the lower part within the set range is further divided into an upper and a lower part by an averaging method, and the above method is repeated to determine the upper and lower superposition relationship of the siltstone layer and the shale layer.

[0156] Step S62: Based on the measured properties of the plurality of siltstone samples and the plurality of mud shale samples, and in accordance with the upper and lower overlapping relationship and the total thickness of the siltstone layer and the total thickness of the mud shale layer, a roof rock sample is prepared by an integrated molding method.

[0157] Step S621: Based on the measured properties of multiple siltstone samples, a first formula for siltstone is prepared by experimental fitting; based on the measured properties of multiple shale samples, a second formula for shale is prepared by experimental fitting.

[0158] In some embodiments, fitting a first formula for preparing siltstone may include: measuring the particle size distribution, mineral composition, porosity, fracture pressure, critical damage strain value for fracture, and minimum starting pressure of rock samples of each siltstone layer within a set range of the overlying stratum, and obtaining the average value of the corresponding parameters by thickness-weighted averaging; preparing a siltstone sample using the average value of the particle size distribution and the average value of the mineral composition of the siltstone layer as the current formula, and adjusting the current formula until the errors between the porosity, fracture pressure, critical damage strain value for fracture, and minimum starting pressure of the currently prepared siltstone sample and the corresponding average values ​​meet an error threshold, thereby obtaining the first formula for preparing siltstone.

[0159] Small-sized samples can be synthesized first, the porosity of the synthesized samples can be measured, and the results can be calibrated with the measurement results of natural samples. Then, the current particle size distribution and mineral composition can be adjusted and optimized, and new artificial samples can be synthesized. Finally, the error between the measurement results of the synthetic samples and the natural samples does not exceed the error threshold (which can be set to 15%).

[0160] In some embodiments, fitting the second formula for preparing mud shale may include: measuring the particle size distribution, mineral composition, TOC, kerogen initial hydrocarbon production temperature, porosity, critical damage strain value for fracture, and fracture pressure of rock samples of each mud shale layer within a set range of the overlying formation, and obtaining the average value of the corresponding parameters by thickness weighting; preparing mud shale samples using the average value of the particle size distribution and the average value of the mineral composition of the mud shale layer as the current formula, and adjusting the current formula until the errors between the TOC, kerogen initial hydrocarbon production temperature, porosity, critical damage strain value for fracture, and fracture pressure of the currently prepared mud shale sample and the corresponding average values ​​all meet the error threshold, thereby obtaining the second formula for preparing mud shale.

[0161] Optionally, in the process of fitting the first and second formulas, the parameters used for calibration may include not only the above parameters but also other parameters. Correspondingly, the measurement results of natural samples of these parameters are obtained by thickness-weighted averaging the measurement results of the corresponding rock samples.

[0162] Step S622: preparing a roof rock sample by integral molding according to the upper and lower overlapping relationship, the total thickness of the siltstone layer and the total thickness of the shale layer, the first formula and the second formula.

[0163] Roof rock samples of the same cross-sectional area (eg cylindrical with a diameter of 5 cm) can be prepared.

[0164] Taking the above setting range of 500 cm thickness as an example, the thickness of the roof rock sample is also 500 cm.

[0165] The sides of the roof rock sample are wrapped with heat-insulating material to prevent heat from being dissipated to the surroundings during heating. The pressure resistance of the heat-insulating sealing material must be no less than 80MPa.

[0166] Step S63: a first heating device, a first pressurizing device, a first stress device and a group of first sensors are arranged on the bottom surface of the roof rock sample, and multiple groups of first sensors are arranged on the side of the roof rock sample at first set intervals, wherein the first sensors include a first temperature sensor, a first pressure sensor and a first strain sensor; the first heating device is used to heat the roof rock sample to a first set temperature at which the temperature measured by the first temperature sensor at the bottom is measured; the first pressurizing device is used to pressurize the roof rock sample to a first set pressure at which the pressure measured by the first pressure sensor at the bottom is measured; the first stress device is used to apply stress to the bottom of the roof rock sample step by step from small to large to a first set stress, and stabilize at the temperature, pressure and stress until the change amplitude of the measured values ​​of each first sensor is less than the set threshold value; and the lower limit of the roof sealing thickness is determined according to the measured values ​​of the first sensors and the upper and lower overlapping relationship.

[0167] In the embodiment of the present application, from bottom to top corresponds to from bottom to top.

[0168] The measurement positions of each group of first temperature sensors, first pressure sensors and first strain sensors arranged on the side of the rock sample in the longitudinal direction are consistent.

[0169] The first pressurizing device may be a fluid pressurizing device; and the first stress device may be a triaxial stress testing device.

[0170] In some embodiments, the first heating device is a one-way heating device to save resources.

[0171] The first heating device is located at the center of the bottom surface of the top plate rock sample. Further, the first heating device can directly heat an area of ​​the bottom surface of the top plate rock sample that does not exceed 1 / 4 of the bottom surface area, so that the heat source can be spread upward as much as possible.

[0172] The first temperature sensor and the first strain sensor are arranged axially on the side of the roof rock sample. The first set interval of the arrangement is set according to the measurement accuracy requirement, and is usually 10 cm.

[0173] In some embodiments, the first set temperature is the lowest temperature at which the kerogen conversion rate in the shale reservoir reaches a set conversion rate threshold.

[0174] The first set temperature can be determined by using a source rock thermal simulation experiment or a kerogen activation energy experiment.

[0175] For example, multiple samples of shale reservoirs are taken, and source rock thermal simulation experiments are conducted on each sample to measure the lowest temperature at which the kerogen conversion rate reaches a set conversion rate threshold, and the minimum value of the multiple measured minimum temperatures is determined as the first set temperature.

[0176] Furthermore, the first set temperature is the lowest temperature at which the kerogen conversion rate in the shale reservoir reaches 90%, which is usually 290-330°C.

[0177] The kerogen conversion rate reaches 90%. At this temperature, the reservoir is almost completely converted to hydrocarbons, achieving maximum oil and gas production. That is, this temperature is the highest temperature at which the reservoir can be heated during the in-situ heating and production process of actual shale reservoirs. Therefore, the setting of this temperature ensures the safety and rationality of the determined lower limit of the roof sealing thickness.

[0178] In some embodiments, the first set pressure is the fracture pressure of the shale reservoir, which can be determined through a rock fracture pressure experiment; the first set stress is the maximum principal stress underground at the depth of the bottom surface of the roof rock sample, which is obtained by calculation.

[0179] The first set temperature, i.e., the lowest temperature T0 at which the kerogen conversion rate in the shale reservoir reaches 90%, is determined in the above manner, as is the fracture pressure P0 of the shale reservoir and the maximum underground principal stress Ex at the bottom burial depth of the roof rock sample.

[0180] The first heating device (heat source) is used to slowly heat the sample (no more than 20°C / day), with the maximum temperature of the heat source between 400 and 650°C. The power of the heat source is adjusted to keep the temperature at the bottom of the roof rock sample constant at T0. The first pressurizing device is used to pressurize the bottom of the roof rock sample, using fluid boosting at a boosting rate of no more than 300KPa / day (the specific value is flexibly set according to the on-site construction conditions), so that the pressure at the bottom of the roof rock sample is constant at P0. At the same time, the first stress device is used to gradually apply stress to the bottom of the roof rock sample, increasing by 1MPa for 5 minutes at a time, and finally applying a constant stress of Ex. Furthermore, the stress reaching Ex, the pressure reaching P0, and the temperature reaching T0 are achieved as synchronously as possible. The temperature T0, pressure P0, and stress Ex are kept constant for at least 30 minutes until the change in the measured values ​​of each sensor is less than the set threshold, that is, after the temperature, pressure, and strain are stable, the measured values ​​of the first temperature sensor, the first pressure sensor, and the first strain sensor are collected. Since the temperature of the roof rock sample gradually decreases from bottom to top, the pressure gradually decreases from bottom to top, and the strain also gradually decreases from bottom to top, the measured values ​​of the first temperature sensor, the first pressure sensor, and the first strain sensor can be collected from bottom to top in sequence.

[0181] Before determining the lower limit of the roof plugging thickness, the following parameters need to be determined:

[0182] The initial hydrocarbon generation temperature Tx of kerogen in the shale layer of the roof rock sample is usually 200-250°C. It can be determined by thermal simulation experiments of hydrocarbon source rocks;

[0183] The fracture pressure Px of the roof rock sample can be the average value of the fracture pressures of the siltstone layer and the shale layer after weighted average of their thickness;

[0184] The critical damage strain value εx of the roof rock sample can be the average value of the thickness-weighted average of the critical damage strain values ​​of the siltstone layer and the shale layer;

[0185] The minimum starting pressure Ps for oil and gas migration in the siltstone layer in the roof rock sample.

[0186] In some embodiments, the lower limit of the sealing thickness of the roof rock sample is determined based on the measurement value of the first sensor and the vertical superposition relationship between the siltstone layer and the mud shale layer in the roof rock sample, including the following two situations:

[0187] 1. The superposition relationship is that the siltstone layer is on top.

[0188] (1) If the temperature in the shale layer drops to Tx, the pressure drops to Px, and the strain drops to εx, determine the highest position among the positions where the temperature is Tx, the pressure is Px, and the strain is εx, and determine the distance from this position to the bottom surface of the roof rock sample as the lower limit of the roof plugging thickness;

[0189] (2) If the temperature in the mudstone layer drops to Tx, but the pressure does not drop to Px and the strain does not drop to εx at the same time, and the minimum starting pressure of the siltstone layer is greater than the fracture pressure Pr of the shale reservoir, the distance from the higher position of the pressure Px and the strain εx to the bottom surface of the roof rock sample is determined as the lower limit of the roof plugging thickness; if the minimum starting pressure of the siltstone layer is not greater than the fracture pressure Pr of the shale reservoir, it is determined that the roof rock sample cannot be plugged;

[0190] (3) If the temperature in the shale layer is greater than Tx, the method is invalid.

[0191] 2. The superposition relationship is that the siltstone layer is at the bottom.

[0192] (1) If the temperature in the siltstone layer drops to Tx, the pressure drops to Px, and the strain drops to εx, the thickness of the siltstone layer is determined to be the lower limit of the roof seal thickness;

[0193] (2) If the strain in the shale layer drops to εx, or the pressure drops to Px, or the temperature drops to Tx, determine the highest position among the positions where the temperature is Tx, the pressure is Px, and the strain is εx, and determine the distance from this position to the bottom surface of the roof rock sample as the lower limit of the roof plugging thickness.

[0194] In some embodiments, other factors affecting the plugging performance may be further considered to determine a safety correction factor (greater than 1), and the safety correction factor may be used to correct the lower limit of the roof plugging thickness determined above.

[0195] The fifth embodiment of the present invention provides a method for determining the sealing thickness of a complex lithologic layer based on a simplified lithologic combination. A roof rock sample is prepared by integral molding, a first heating device is used to heat the roof rock sample to a first set temperature, a first pressurizing device is used to pressurize the roof rock sample to a first set pressure, and a first stress device is used to gradually apply stress to the bottom of the roof rock sample from small to large to the first set stress, and stabilize at the temperature, pressure, and stress until the measured values ​​of each sensor are stable. The lower limit of the sealing thickness of the roof rock sample is determined based on the measured values ​​of the sensors and the relationship between the upper and lower superposition of the siltstone layer and the mudstone layer. The lower limit of the roof sealing thickness of the shale reservoir is determined by experimental methods based on the simulation of the temperature field, pressure field, and stress field, and the roof sealing conditions of the shale reservoir in situ process are specifically quantified, which can effectively guide production and improve the economic benefits of in-situ mining of shale oil and gas.

[0196] The fifth embodiment of the present invention provides a method for determining the sealing thickness of a complex lithologic layer based on a simplified lithologic combination. Based on the vertical lithologic distribution characteristics of the overlying strata within a set range, the vertical superposition relationship of the siltstone layer and the mudstone layer, as well as the total thickness of the siltstone layer and the total thickness of the mudstone layer are determined. Based on the measured properties of the siltstone and mudstone, a roof rock sample is prepared in one piece. The prepared synthetic sample takes into account both the properties of the mudstone and siltstone, as well as their vertical superposition relationship, and rationally simplifies the sample, thereby enabling the determination of the lower limit of the sealing thickness of the complex lithologic roof interbedded with mudstone and siltstone.

[0197] It is generally believed that only mud shale can effectively seal shale reservoirs during in-situ mining. The method provided in Example 5 of the present invention for determining the sealing thickness of complex lithologic layers based on a simplified lithologic combination suggests that if the overlying rock layer of the shale reservoir is an interbedded layer of siltstone and mud shale, a sealing effect may also be achieved during in-situ mining of the shale reservoir, thereby broadening the exploration prospects of shale oil and gas.

[0198] Example 6

[0199] The sixth embodiment of the present invention provides a specific application of a multi-dimensional and multi-parameter characterization method for a heated rock mass in an in-situ conversion stage of shale oil, comprising the following steps:

[0200] S1: In this example, five wells in the shale oil in-situ conversion development block were selected as evaluation wells, of which two wells were used to conduct systematic core sampling and lithologic fine evaluation of the rock mass to be heated and its overlying and underlying rock formations (both with a thickness of not less than 5m each). Figure 7 The two core wells are located in the middle of the development block, at the two ends of the long axis of the rock mass to be heated.

[0201] S2: Using the coring wells, a logging lithologic interpretation model based on the lithologic binarization of the organic-rich shale section (organic-rich shale, interlayer) is established. Using the TOC detection data of the coring well system, a logging TOC interpretation model is established. Using the lithologic data and TOC data, a single-well comprehensive histogram of the organic-rich shale section is established, which includes the binarized lithologic profile and the TOC profile. In this embodiment, the lithologic data described by the cores and the measured TOC data of the two coring wells are used to map ( Figure 7 ), lithologic and TOC data from three uncored wells were mapped using logging data and logging interpretation models.

[0202] S3: Using samples from the overlying and underlying rock formations of the organic-rich shale section from two coring wells, a simulation experiment was conducted to evaluate the lower limit of the top and bottom plate thickness of the heated rock mass. The core of the experiment is to determine the relationship between the maximum breakthrough pressure of different lithology samples in the overlying and underlying rock formations of the organic-rich shale section and the thickness of the rock of that lithology. Through the experiment, it is determined that the breakthrough pressure of different lithology samples reaches the corresponding thickness of the top and bottom plates. In this embodiment, the top and bottom plate thicknesses determined by coring well 1 are 6.1m and 3.6m respectively; the top and bottom plate thicknesses determined by coring well 2 are 6.2m and 2.9m respectively. Figure 7 ).

[0203] Well logging lithology calibration was used to establish a well logging lithology interpretation model for different roof and floor lithologies. In three uncored wells, well logging interpretation was used to determine the lithology of the overlying and underlying strata of the organic-rich shale interval, and thus the roof and floor thicknesses of these three wells were determined.

[0204] S4: Divide the heating formation units using the comprehensive histogram of the organic-rich shale section containing the binary lithologic profile and TOC profile established in step S2. Taking the coring well 1 of this embodiment as an example, the organic-rich shale section (the shale section to be heated) of the well is divided into three heating formation units. The three have obvious differences in the overall value distribution of TOC and lithologic combination: the TOC of the T1 section is the highest overall, with no sandstone interlayers; the TOC of the T2 section is second overall, with a small amount of thin sandstone interlayers; the TOC of the T3 section is the lowest overall, with relatively developed sandstone interlayers ( Figure 8 ).

[0205] S5: This example shows the comparison of well connections in the long axis direction of the shale oil in-situ conversion development block ( Figure 9 The single-well histogram of the well-connected profile includes a binary lithologic profile of the heated rock mass and a TOC profile. Heating stratigraphic units are delineated within the individual wells, and the lateral distribution of heated stratigraphic units and interlayers is subsequently determined through well-connected comparison.

[0206] S6: Determine the thickness of the heated rock mass, the TOC average value per well, and the thickness of the roof and bottom plates in each well. Using the single well data, the planar distribution of the heated rock mass thickness, the heated rock mass TOC, and the roof and bottom plates is determined by interpolation. This example shows a planar distribution diagram of the heated rock mass thickness and the roof plate thickness ( Figure 10 、 Figure 11 ).

[0207] S7: Refer to the well cross-section diagram determined in step S5 and the various plan diagrams determined in step S6, analyze and evaluate the distribution and change trends of various parameters between wells, and establish a well grid diagram covering the entire shale oil in-situ conversion development block. The grid diagram shows the three-dimensional spatial distribution of the heating formation units and interlayers in the entire development block ( Figure 12 ).

[0208] Based on the inventive concept of the present invention, the embodiment of the present invention also provides a multi-dimensional and multi-parameter characterization device for heating rock mass in the in-situ conversion stage of shale oil. The structure of the device is as follows: Figure 13 As shown, it includes a binary lithologic data acquisition module 131, a heated rock mass division module 132, an interlayer identification module 133, a heated rock mass distribution feature research module 134, and an interlayer single layer thickness lower limit determination module 135;

[0209] Binary lithologic data acquisition module 131 is used to acquire binary lithologic data of organic-rich shale development segments developed in target layers in the studied block, wherein the binary lithologic data include organic-rich shale and non-organic-rich shale;

[0210] A heated rock mass division module 132 is configured to identify at least one pseudo-in-situ conversion section within the organic-rich shale development section based on a set upper limit of the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithologic data, and to divide the pseudo-in-situ conversion section into at least one heated rock mass based on the distribution characteristics of the binary lithologic properties and TOC distribution characteristics;

[0211] The interlayer identification module 133 is configured to identify a non-organic-rich shale single layer in the heated rock mass. If the thickness of the non-organic-rich shale single layer is greater than the lower limit of the thickness of the single layer used as an interlayer in the simulated in-situ conversion stage, the non-organic-rich shale single layer is identified as an interlayer. The lower limit of the thickness of the single layer is predetermined by the interlayer single layer thickness lower limit determination module 135 based on the average hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and multiple data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value.

[0212] The heated rock mass distribution characteristic research module 134 is used to establish a well-connected grid diagram of the drilled wells, and complete the spatial distribution research of the heated rock mass and the interlayer in each well-connected section in the well-connected grid diagram based on the heated rock mass and interlayer identification results of the single well.

[0213] In some embodiments, the apparatus further includes a lithologic identification model building module 136. If no coring is performed in the target layer after the well has been drilled, the binary lithologic data acquisition module 131 is configured to acquire binary lithologic data of the organic-rich shale development section of the drilled well in the following manner:

[0214] The sensitivity curve of the drilled well is input into the lithologic identification model, and the binary lithologic data of the organic-rich shale development section is obtained according to the output of the model. The lithologic identification model is pre-established by the lithologic identification model establishment module 136 in the following manner:

[0215] The GR value lower limit of organic-rich shale is determined based on the binary lithologic data of the coring section of the target layer of the sample well; the binary lithologic data of the coring section and the curve segment of the selected sensitivity curve are used as a sample to establish a sample set; the selected neural network model is trained using the sample set to establish a lithologic identification model, and the GR value lower limit is input into the lithologic identification model. The GR value lower limit is used to locate the organic-rich shale development section.

[0216] In some embodiments, the heated rock mass division module 132 is configured to divide the quasi-in-situ conversion section into at least one heated rock mass according to the following principles:

[0217] The TOC difference between the heated rock mass in the in-situ conversion section of shale oil and the adjacent heated rock mass meets the first set difference, and / or the lithology combination difference between the heated rock mass and the adjacent heated rock mass meets the second set difference.

[0218] In some embodiments, the lithology identification model building module 36 is used to obtain the binary lithology data of the core section of the target layer of the sample well in the following manner:

[0219] Based on the thin section identification data of the core sampling section of the target layer of the sample well, the lithologic description data in the core description data is corrected to obtain preliminary lithologic data, wherein the preliminary lithologic data includes mud shale; based on the TOC detection data, the mud shale in the preliminary lithologic data having a TOC value greater than a preset lower limit of the TOC of organic-rich shale is determined to be organic-rich shale, thereby obtaining binary lithologic data of the core sampling section.

[0220] In some embodiments, the lithology identification model establishment module 136 is used to extract the lithology and GR value of the sampling points with thin section identification data and TOC detection data based on the binary lithology data and GR curve of the sample well; and statistically obtain the lower limit of the GR value of organic-rich shale based on the lithology and GR values ​​of multiple sampling points.

[0221] In some embodiments, the interlayer single layer thickness lower limit determination module 135 is used to predetermine the lower limit of the thickness of the single layer of the interlayer to be used as the proposed in-situ conversion section by:

[0222] Based on each of the data pairs, a sample point is obtained, including the thickness of the non-organic-rich shale single layer and the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the organic-rich shale single layer; the sample point is projected into a coordinate system, and a trend line is obtained by fitting. Based on the trend line, the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the organic-rich shale single layer is determined to be the thickness of the non-organic-rich shale single layer corresponding to the set ratio, and this thickness is determined as the lower limit of the single layer thickness of the non-organic-rich shale single layer as an interlayer in the simulated in situ conversion section.

[0223] In some embodiments, the interlayer single layer thickness lower limit determination module 135 is configured to obtain an average hydrocarbon generation potential value of an organic-rich shale single layer in the shale layer and a plurality of data pairs including the thickness of a non-organic-rich shale single layer and its hydrocarbon generation potential value in the following manner:

[0224] Based on centimeter-level core description data of continuous coring sections within a shale layer, a pseudo-in situ conversion section is identified from the coring section, and the identified pseudo-in situ conversion section is divided into multiple units according to sedimentary cycles. The type of each unit is determined according to its thickness ratio to the pseudo-in situ conversion section, and at least one unit of each type is screened; a millimeter-level binary lithologic description is performed on the screened units, and based on the description results, the units are divided into multiple organic-rich shale single layers and non-organic-rich shale single layers. Rock samples are cut from the single layers, and the hydrocarbon generation potential of the rock samples is determined through pyrolysis testing; and the average hydrocarbon generation potential of the organic-rich shale single layers and multiple data pairs including the thickness of the non-organic-rich shale single layers and their hydrocarbon generation potential values ​​are statistically obtained.

[0225] In some embodiments, the interlayer single layer thickness lower limit determination module 135 is configured to:

[0226] Each unit is classified into one of the following types:

[0227] The thickness ratio of the proposed in-situ conversion section is less than 1%, the thickness ratio of the proposed in-situ conversion section is not less than 1% and not more than 5%, the thickness ratio of the proposed in-situ conversion section is greater than 5% and not more than 10%, and the thickness ratio of the proposed in-situ conversion section is greater than 10%.

[0228] In some embodiments, the heated rock mass distribution characteristics research module 134 is further configured to:

[0229] For each heated rock mass, the heated rock mass thickness, interlayer thickness and interlayer thickness ratio of a single well are counted, and the heated rock mass thickness plane map, interlayer thickness plane map and interlayer thickness ratio plane map are drawn by interpolation method.

[0230] Regarding the apparatus in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0231] Based on the inventive concept of the present invention, an embodiment of the present invention further provides a computer storage medium, in which computer executable instructions are stored. When the computer executable instructions are executed by a processor, the above-mentioned method for identifying heated rock interlayers in the in-situ conversion section of shale oil is implemented.

[0232] Based on the inventive concept of the present invention, an embodiment of the present invention also provides a server, including: a memory, a processor, and a computer program stored in the memory and runnable on the processor, wherein when the processor executes the program, the above-mentioned method for identifying heated rock interlayers in the in-situ conversion section of shale oil is implemented.

[0233] Unless otherwise specifically stated, terms such as process, calculate, compute, determine, display, and the like may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, that manipulate and convert data represented as physical (e.g., electronic) quantities within registers or memories of a processing system into other data similarly represented as physical quantities within the memories, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0234] It should be understood that the specific order or hierarchy of steps in the disclosed processes is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0235] In the foregoing detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that embodiments of the claimed subject matter require more features than are recited in each claim. On the contrary, as reflected in the appended claims, the invention comprises less than all the features of any individual disclosed embodiment. The appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0236] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein may be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described around their functions. Whether such functions are implemented as hardware or software depends on the specific application and the design constraints imposed on the entire system. A skilled person may implement the described functions in an adaptable manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of this disclosure.

[0237] The steps of the methods or algorithms described in conjunction with the embodiments herein may be directly embodied as hardware, software modules executed by a processor, or a combination thereof. The software module may be located in a RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, register, hard disk, removable disk, CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and storage medium may also be present in a user terminal as discrete components.

[0238] For software implementation, the techniques described in this application can be implemented using modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or external to the processor. In the latter case, it is communicatively coupled to the processor via various means, which are well known in the art.

[0239] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it will be appreciated by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to encompass all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is encompassed in a manner similar to the term "including," as explained in terms of "including," used as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or." The terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.

Claims

1. A multi-dimensional and multi-parameter characterization method for heated rock mass in the in-situ conversion stage of shale oil, characterized in that: include: Obtaining binary lithologic data of organic-rich shale development sections developed in target layers drilled in the study area, wherein the binary lithologic data includes organic-rich shale and non-organic-rich shale; identifying at least one pseudo-in-situ conversion section within the organic-rich shale development section based on a set upper limit for the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithologic data, and dividing the pseudo-in-situ conversion section into at least one heated rock mass based on the distribution characteristics of the binary lithologic properties and TOC distribution characteristics; Identifying a non-organic-rich shale single layer in the heated rock mass, and identifying the non-organic-rich shale single layer as an interlayer if the thickness of the non-organic-rich shale single layer is greater than a lower limit of the thickness of the single layer for being an interlayer in the simulated in-situ conversion section, wherein the lower limit of the thickness of the single layer is predetermined based on an average hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and a plurality of data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value; A well-connected grid diagram of the drilled wells is established, and based on the identification results of the heated rock mass and interlayer of a single well, a spatial distribution study of the heated rock mass and the interlayer in each well-connected section in the well-connected grid diagram is completed.

2. The method according to claim 1, characterized in that If no coring is done in the target layer, the binary lithologic data of the organic-rich shale development section can be obtained by the following method: The sensitivity curve of the drilled well is input into the lithologic identification model. Based on the output of the model, the binary lithologic data of the organic-rich shale development section is obtained. The lithologic identification model is pre-established in the following manner: The GR value lower limit of organic-rich shale is determined based on the binary lithologic data of the coring section of the target layer of the sample well; the binary lithologic data of the coring section and the curve segment of the selected sensitivity curve are used as a sample to establish a sample set; the selected neural network model is trained using the sample set to establish a lithologic identification model, and the GR value lower limit is input into the lithologic identification model. The GR value lower limit is used to locate the organic-rich shale development section.

3. The method according to claim 2, characterized in that The model output result is obtained from the lithology identification model in the following way: Locating the organic-rich shale development section based on the GR value lower limit and the GR curve of the drilled well; According to the neural network learning result of the sensitive curve segment corresponding to the organic-rich shale development segment, the binary lithologic data thereof is determined to obtain a result for output.

4. The method according to claim 2, characterized in that The binary lithologic data of the core section of the target layer of the sample well is obtained by the following method: According to the thin section identification data of the core section of the target layer of the sample well, the lithology description data in the core description data is corrected to obtain preliminary lithology data, wherein the preliminary lithology data includes mud shale; According to the TOC detection data, the mud shale with a TOC value greater than a preset lower limit of TOC of organic-rich shale in the preliminary lithological data is determined as organic-rich shale, and the binary lithological data of the coring section is obtained.

5. The method according to claim 4, characterized in that Determining the lower limit of the GR value of organic-rich shale includes: Based on the binary lithologic data and GR curve of the sample well, the lithologic properties and GR values ​​of the sampling points with thin section identification data and TOC detection data are extracted; Based on the lithology and GR values ​​of multiple sampling points, the lower limit of the GR value of organic-rich shale was obtained statistically.

6. The method according to claim 1, characterized in that The step of dividing the quasi-in-situ conversion section into at least one heated rock mass comprises: The quasi-in-situ conversion section is divided into at least one heated rock mass according to the following principles: The TOC difference between the heated rock mass and the adjacent heated rock mass satisfies a first set difference, and / or the lithology combination difference between the heated rock mass and the adjacent heated rock mass satisfies a second set difference.

7. The method according to claim 6, characterized in that The first set difference includes an overall TOC value difference and / or an overall TOC curve morphology difference; The second set difference includes a difference in the number of non-organic-rich shale layers and / or a difference in the thickness of the non-organic-rich shale layers.

8. The method according to claim 1, characterized in that The lower limit of the thickness of the non-organic-rich shale monolayer as the interlayer of the simulated in-situ conversion section is predetermined by the following method: According to each data pair, a sample point is obtained, which includes the ratio of the thickness and hydrocarbon generation potential value of the non-organic-rich shale single layer to the average hydrocarbon generation potential value of the organic-rich shale single layer; The sample points are projected into a coordinate system, and a trend line is obtained by fitting. Based on the trend line, the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the organic-rich shale single layer is determined to be the thickness of the non-organic-rich shale single layer corresponding to the set ratio. This thickness is determined as the lower limit of the thickness of the non-organic-rich shale single layer as an interlayer in the simulated in-situ conversion section.

9. The method according to claim 2, characterized in that The average value of the hydrocarbon generation potential value of a single layer of organic-rich shale in the shale layer and a plurality of data pairs including the thickness of a single layer of non-organic-rich shale and its hydrocarbon generation potential value are obtained by the following method: Based on the binary lithologic data of the cored section of the target layer of the sample well and the upper limit of the proportion of non-organic-rich shale in the in-situ conversion section, a pseudo-in-situ conversion section is identified from the cored section, the identified pseudo-in-situ conversion section is divided into a plurality of units according to the sedimentary cycle, the type of each unit is determined according to the thickness ratio of each unit to the pseudo-in-situ conversion section, and at least one unit is selected from each type of unit; Conduct millimeter-level binary lithologic descriptions on the selected units. Based on the description results, the units are divided into multiple organic-rich shale layers and non-organic-rich shale layers. Rock samples are cut from the layers and their hydrocarbon generation potential is determined through pyrolysis testing. The average value of the hydrocarbon generation potential value of the organic-rich shale single layer and multiple data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value are statistically obtained.

10. The method according to claim 9, characterized in that The method of determining the type of each unit according to the thickness ratio of the proposed in-situ conversion section includes: Each unit is classified into one of the following types: The thickness ratio of the proposed in-situ conversion section is less than 1%, the thickness ratio of the proposed in-situ conversion section is not less than 1% and not more than 5%, the thickness ratio of the proposed in-situ conversion section is greater than 5% and not more than 10%, and the thickness ratio of the proposed in-situ conversion section is greater than 10%.

11. The method according to claim 1, wherein It also includes, for each heated rock mass, counting the heated rock mass thickness, interlayer thickness and interlayer thickness ratio of a single well, and drawing the heated rock mass thickness plane map, interlayer thickness plane map and interlayer thickness ratio plane map by interpolation method.

12. The method according to any one of claims 1 to 11, characterized in that: The hydrocarbon generation potential value is the sum of free hydrocarbons S1 and pyrolysis hydrocarbons S2 per unit mass of rock.

13. The method according to any one of claims 1 to 11, characterized in that: The upper limit of the proportion of non-organic-rich shale in the in-situ conversion stage is 20%.

14. A multi-dimensional and multi-parameter characterization device for heated rock mass in the in-situ conversion stage of shale oil, characterized in that: The device includes a binary lithologic data acquisition module, a heated rock mass division module, an interlayer identification module, a heated rock mass distribution feature research module, and an interlayer single layer thickness lower limit determination module; The binary lithologic data acquisition module is used to acquire binary lithologic data of the organic-rich shale development section developed in the target layer of the well drilled in the study block, wherein the binary lithologic data includes organic-rich shale and non-organic-rich shale; The heated rock mass division module is configured to identify at least one pseudo-in-situ conversion section within the organic-rich shale development section based on a set upper limit of the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithologic data, and to divide the pseudo-in-situ conversion section into at least one heated rock mass based on the distribution characteristics of the binary lithologic properties and the TOC distribution characteristics; The interlayer identification module is configured to identify a non-organic-rich shale single layer in the heated rock mass. If the thickness of the non-organic-rich shale single layer is greater than a lower limit of the thickness of the single layer used as an interlayer in the simulated in-situ conversion section, the non-organic-rich shale single layer is identified as an interlayer. The lower limit of the thickness of the single layer is predetermined by the interlayer single layer thickness lower limit determination module based on an average hydrocarbon generation potential value of the organic-rich shale single layer in the shale layer and a plurality of data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value. The heated rock mass distribution feature research module is used to establish a well-connected grid diagram of the drilled wells, and based on the heated rock mass and interlayer identification results of a single well, complete the spatial distribution research of the heated rock mass and the interlayer in each well-connected section in the well-connected grid diagram.

15. A computer storage medium, characterized in that The computer storage medium stores computer executable instructions, which, when executed by a processor, implement the multi-dimensional and multi-parameter characterization method for heated rock mass in the in-situ conversion section of shale oil as described in any one of claims 1 to 13.

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