Method and device for identifying heating rock mass interlayer in shale oil in-situ conversion section

Abstract

The invention discloses a shale oil in-situ conversion section heating rock mass interlayer identification method and device, and the method comprises the steps: inputting a sensitive curve of a target well into a lithology identification model, and obtaining the binary lithology data of a rich shale development section according to a model output result; identifying at least one quasi-in-situ conversion section according to the upper limit of the proportion of the non-rich organic matter shale in the set in-situ conversion section and the binarization lithologic data; dividing the quasi-in-situ conversion section into at least one heating rock mass according to the distribution characteristics of the binarization lithology and the TOC distribution characteristics; identifying a non-rich organic matter shale single layer in the heated rock mass, and if the thickness of the non-rich organic matter shale single layer is larger than the lower limit of the thickness of the single layer serving as the quasi-in-situ conversion section interlayer, identifying the non-rich organic matter shale single layer as the interlayer. According to the method, the binarized logging lithology interpretation result and the organic matter abundance can be combined to finely divide the heating rock mass; the lower limit value of the hydrocarbon generation potential of the interlayer is converted into the lower limit value of the thickness of the interlayer which is more visual and easier to obtain, and the interlayer in the heated rock mass is visually recognized.

Description

Technical Field

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

[0002] my country has conducted a lot of research on the in-situ conversion of oil shale and accumulated rich research experience. Different in-situ heating methods for shale, such as convection heating, electric heating, and microwave heating, have been studied and demonstrated. These research results have laid a solid foundation for further research and development of in-situ conversion technology for shale oil. In recent years, phased understanding and technical progress have been made in the evaluation and optimization of favorable areas and sweet spots for in-situ conversion and development of medium- and low-maturity shale oil (Yang Zhi, Zou Caineng, Fu Jinhua, et al. Evaluation of terrestrial shale selection based on in-situ conversion / modification technology - taking the shale of the 7th section of the Triassic Yanchang Formation in the Ordos Basin as an example, 2017; Patent authorization announcement number: CN 109113730 B).

[0003] Analyzing the previous research results, the research on the determination of the vertical heating section for in-situ conversion of low-middle-mature organic-rich shales is relatively weak. In the research on in-situ heating development of oil shale, the oil shale layer is generally regarded as the target layer for development; in the research on in-situ conversion of shale oil, the determination of the heating section has been deepened, but only five conditions that the heating section must meet have been determined (Zhao Wenzhi, Hu Suyun, Hou Lianhua. The connotation and strategic position of underground in-situ conversion of shale oil, 2018). Summary of the invention

[0004] The inventors found that due to the complex and changeable geological conditions of the continental shale formation, my country's organic-rich shale sections often show more significant heterogeneity, which is manifested in the high development of non-shale interlayers and the heterogeneity of the quality of shale source rocks. In the in-situ conversion and heating stage of shale oil, non-shale interlayers and low hydrocarbon generation potential interlayers may differ from organic-rich shales in terms of heat transfer efficiency, thermal cracking, hydrocarbon generation, etc.; in the production stage after the in-situ conversion of shale oil to generate oil and gas on a large scale, interlayers may also differ significantly from organic-rich shales in terms of fracture development, physical properties, and oil and gas saturation (for example, the poor ability of interlayers to generate fractures plays a role in blocking oil and gas transmission). These differences will have an impact on the selection of the optimal heating section, well pattern, and well spacing design during the in-situ conversion and development of shale oil. Based on this, it is very necessary to finely divide the heating unit of the in-situ conversion heating section of shale oil from the two aspects of lithology and hydrocarbon generation potential.

[0005] In order to at least partially solve the technical problems existing in the prior art, the inventors have made the present invention, and through a specific implementation method, provide a method and device for identifying interlayers in the heated rock mass of the in-situ conversion section of shale oil, conduct a detailed evaluation of the spatial distribution of lithology and organic matter abundance in the heating section of the in-situ conversion of shale oil, and then divide the heated rock mass of the heating section; on this basis, identify interlayers based on hydrocarbon generation potential, and provide important data basis for realizing the efficient development of in-situ conversion of shale oil.

[0006] In a first aspect, an embodiment of the present invention provides a method for identifying interlayers in a heated rock mass in an in-situ conversion stage of shale oil, comprising:

[0007] The sensitivity curve of the target well in the shale layer is input into the lithology identification model, and the binary lithology data of the organic-rich shale development section including organic-rich shale and non-organic-rich shale are obtained according to the output of the model;

[0008] According to the set upper limit of the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithology data, at least one pseudo-in-situ conversion section is identified from the organic-rich shale development section, and according to the distribution characteristics of the binary lithology and the TOC distribution characteristics, the pseudo-in-situ conversion section is divided into at least one heated rock mass;

[0009] A non-organic-rich shale monolayer in a heated rock mass is identified. If the thickness of the non-organic-rich shale monolayer is greater than the lower limit of the monolayer thickness as an interlayer of a simulated in-situ conversion section, the non-organic-rich shale monolayer is identified as an interlayer. The lower limit of the monolayer thickness is predetermined based on an average value of the hydrocarbon generation potential of the organic-rich shale monolayer in the shale layer and a plurality of data pairs including the thickness of the non-organic-rich shale monolayer and its hydrocarbon generation potential.

[0010] In a second aspect, an embodiment of the present invention provides a device for identifying interlayers in a heated rock mass in an in-situ conversion stage of shale oil, the device comprising a binary lithology prediction module, a heated rock mass division module, an interlayer identification module, a lithology identification model establishment module, and an interlayer single layer thickness lower limit determination module;

[0011] The binary lithology prediction module is used to input the sensitivity curve of the shale layer target well into the lithology identification model, and obtain the binary lithology data of the organic-rich shale development section including organic-rich shale and non-organic-rich shale according to the model output result. The lithology identification model is pre-established by the lithology identification model establishment module;

[0012] The heated rock mass division module is used to identify at least one pseudo-in-situ conversion section from 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 lithology data, and divide the pseudo-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;

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

[0014] In a third aspect, an embodiment of the present invention provides a computer storage medium, wherein the computer storage medium stores computer executable instructions, and 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.

[0015] 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 the processor implements the above-mentioned method for identifying heated rock interlayers in the in-situ conversion section of shale oil when executing the program.

[0016] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0017] (1) The method for identifying the interlayer of 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 lithology logging interpretation, identifies the quasi-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 based on the binary lithology difference and TOC difference for the quasi-in-situ conversion section, making it possible to adopt different well layout methods, heating schemes and subsequent oil and gas development schemes for heated rock masses with different geological and geochemical conditions, and providing an important geological evaluation means for the scale-effective development of in-situ conversion of shale oil. That is, the on-site significance of this achievement is to make it possible to design the in-situ conversion development scheme in a refined and differentiated manner.

[0018] (2) The method for identifying interlayers in heated rock mass in the in-situ conversion section of shale oil provided in an embodiment of the present invention predetermines the lower limit of the single-layer thickness of the non-organic-rich shale as the interlayer of the proposed in-situ conversion section based on the average value of the hydrocarbon generation potential 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 the interlayer, it is determined to be an interlayer. First, this method is targeted at specific application scenarios of organic-rich shale development sections, breaking the limitations of traditional interlayer identification that relies solely on lithology, and is more suitable for geological evaluation and related research on in-situ conversion of shale oil; 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 proposed 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 thickness of the interlayer in this way 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 and the faster the deposition rate, the more difficult it is to enrich the organic matter, and the worse the hydrocarbon generation potential is.

[0019] (3) The shale interlayer identification method based on hydrocarbon generation potential and lithology binarization provided in the embodiment of the present invention determines that 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 are the average value of the hydrocarbon generation potential 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 lithology 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 identified pseudo-in-situ conversion section is divided into multiple units, and the type of each unit is determined according to the thickness ratio of the pseudo-in-situ conversion section, and at least one unit is selected from each type of unit; millimeter-level lithology description is carried out on the selected units, and the units are divided into multiple organic-rich shale single layers and non-organic-rich shale single layers according to the description results. Rock samples are cut from the single layers, and the hydrocarbon generation potential of the rock samples is determined by pyrolysis test; the average value of the hydrocarbon generation potential of the organic-rich shale single layer and multiple data pairs containing the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential are statistically obtained. Taking into full consideration the geological characteristics of the continental shale formation, such as rapid lithology changes and thin single layer thickness, the basic workload is greatly reduced through lithology combination division, multi-level core fine description, and multi-scale sampling layer screening, while taking into account the lithology representativeness and high sampling accuracy of the collected samples.

[0020] (4) The method for identifying interlayers in heated rock mass in the in-situ conversion section of shale oil provided in the embodiment of the present invention is aimed at the specific scenario of lithology identification of thin interlayers in the organic-rich shale development section. It abandons the universal pursuit of conventional well logging lithology interpretation to interpret and characterize various lithologies developed in the study area separately, and limits the lithology interpretation objects to two types: organic-rich shale and non-organic-rich shale, thereby reducing the multi-solution of well logging lithology interpretation and improving the interpretation accuracy; at the same time, it reduces the amount of calculation and improves the recognition speed of batch interpretation of multiple wells.

[0021] (5) The method for identifying interlayers in heated rock mass in the in-situ conversion stage of shale oil provided by the embodiment of the present invention only needs to use the core data of the sample well in the stage of establishing the lithology identification model. Once the modeling is completed, only conventional logging curves need to be used in the application stage to achieve accurate lithology characterization of organic-rich shale binary. Under the premise of ensuring the accuracy of interpretation, the requirements for data quality are greatly reduced.

[0022] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose 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.

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] 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:

[0025] Figure 1 This is a flow chart of a method for determining a lower limit of the thickness of a single layer of non-organic-rich shale as an interlayer in Example 1 of the present invention;

[0026] Figure 2 This is a flow chart of a method for establishing a lithology identification model for an organic-rich shale development segment based on lithology binarization in Embodiment 2 of the present invention;

[0027] Figure 3 This is a flow chart of a method for identifying interlayers in a heated rock mass in an in-situ conversion stage of shale oil in Embodiment 3 of the present invention;

[0028] Figure 4 A comprehensive histogram of sample wells selected in the fourth embodiment of the present invention;

[0029] Figure 5 This is a schematic diagram of the division of the heated rock mass in the shale oil in-situ conversion heating section in the fourth embodiment of the present invention;

[0030] Figure 6 The typical anatomical well histogram and the distribution of three sampling points in the fifth embodiment of the present invention;

[0031] Figure 7 for Figure 6 The millimeter-level silt interlayer, shale single layer division and sampling plan diagram of "Sampling Point 1" in the figure;

[0032] Figure 8 for Figure 6 The millimeter-level silt interlayer, shale single layer division and sampling plan diagram of "sampling point 2" and "sampling point 3";

[0033] Fig. 9 A graph showing the relationship between the ratio of the average value of the hydrocarbon generation potential of the sandstone single layer to that of the shale and the thickness of the sandstone single layer in Example 5 of the present invention;

[0034] Fig.10 for Figure 6 "Sampling point 1" is based on the comparison between the lithology profile evaluated in this embodiment and the conventional lithology profile;

[0035] Fig.11 It is a schematic diagram of the structure of the heated rock interlayer identification device in the in-situ conversion section of shale oil in an embodiment of the present invention. DETAILED DESCRIPTION

[0036] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the 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. On the contrary, 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.

[0037] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0038] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings 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 a conflict with any incorporated document, the content of this specification shall prevail.

[0039] The embodiment of the present application divides organic-rich shale and non-organic-rich shale based on the TOC lower limit of organic-rich shale. Specifically, the lithology of rocks with TOC greater than the lower limit is defined as organic-rich shale; and the lithology of rocks with TOC not greater than the lower limit is defined as non-organic-rich shale.

[0040] 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.

[0041] Embodiment 1

[0042] Embodiment 1 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 of a shale layer, specifically determining the lower limit of the thickness of the non-organic-rich shale interlayer identified from the pseudo-in-situ conversion section in the shale layer, referring to Figure 1 As shown, the following steps are included:

[0043] Step S11: According to the binary lithology data of the core 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 quasi-in-situ conversion section from the core section, divide the identified quasi-in-situ conversion section into multiple units, determine the type of each unit according to the thickness ratio of the quasi-in-situ conversion section, and select at least one unit from each type of unit.

[0044] First, typical dissected wells used to identify interlayers with low hydrocarbon generation potential are selected. Generally, typical dissected wells must meet the following requirements:

[0045] (1) The dissecting well must be located in the shale oil in-situ conversion development block, or at least adjacent to the development block;

[0046] (2) at least one well;

[0047] (3) There is a continuous coring section in the shale section to be heated for in-situ conversion of shale oil.

[0048] Binary lithology 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, and the acquisition process includes the following as described in Example 2.

[0049] The binary lithology data of the coring section here needs to be centimeter-level lithology data.

[0050] The thickness of 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.

[0051] The upper limit of the proportion of non-organic-rich shale in the in-situ conversion stage can usually be set to 20%. Optionally, it can also be set to other values ​​according to relevant regulations or actual research needs.

[0052] 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.

[0053] Each unit is classified into one of the following types according to its thickness ratio to the proposed in-situ conversion section:

[0054] (1) The thickness ratio of the proposed in-situ conversion section is less than 1%,

[0055] (2) The thickness ratio of the proposed in-situ conversion section is not less than 1% and not more than 5%,

[0056] (3) The thickness ratio of the proposed in-situ conversion section is greater than 5% and less than 10%,

[0057] (4) The thickness ratio of the proposed in-situ conversion section is greater than 10%.

[0058] 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 abundance of organic matter in the lithological combination section.

[0059] Screening the same number of units from each type of unit can be done by screening a typical unit from each type of unit, or by screening multiple units if the research time and conditions permit.

[0060] Step S12: Perform millimeter-level binary lithology description on the screened units, divide the units into multiple organic-rich shale monolayers and non-organic-rich shale monolayers according to the description results, cut rock samples from the monolayers, and determine the hydrocarbon generation potential of the rock samples through pyrolysis testing.

[0061] Based on the millimeter-level binary lithology description of the selected units, the following steps are performed:

[0062] (1) Using wire cutting technology, cut each lithologic single layer of each unit (sampling layer) along the lithologic single layer plane, and prepare independent flaky rock samples for each lithologic single 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 test 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.

[0063] Step S13: Statistically obtain an average value of the hydrocarbon generation potential value of the organic-rich shale single layer and a plurality of data pairs including the thickness of the non-organic-rich shale single layer and its hydrocarbon generation potential value.

[0064] The data relied on for determining the lower limit of the single-layer thickness of the non-organic-rich shale as an interlayer of the pseudo-in-situ conversion section are the average value of the hydrocarbon generation potential 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, which are obtained in the following way: according to the binary lithology 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; 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 the pseudo-in-situ conversion section, and at least one unit is selected from each type of unit; millimeter-level lithology description is carried out on the selected units, and the units are divided into multiple organic-rich shale single layers and non-organic-rich shale single layers according to the description results, rock samples are cut from the single layers, and the hydrocarbon generation potential of the rock samples is determined by pyrolysis test; the average value of the hydrocarbon generation potential 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 are statistically obtained. Fully considering the geological characteristics of continental shale formations such as rapid lithology changes and thin single layer thickness, through lithology combination division, multi-level core detailed description, and multi-scale sampling layer screening, the basic workload was greatly reduced while taking into account the lithology representativeness and high sampling accuracy of the collected samples.

[0065] Step S14: 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 layer to the average value of the hydrocarbon generation potential value of the organic-rich shale layer.

[0066] Step S15: Project the sample points into a coordinate system, obtain a trend line by fitting, and determine the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the organic-rich shale single layer according to the trend line as the thickness of the non-organic-rich shale single layer corresponding to the set ratio, and determine the thickness as the lower limit of the single layer thickness of the non-organic-rich shale single layer as the interlayer of the quasi-in-situ conversion section.

[0067] The coordinate system uses the thickness of a single layer of non-organic-rich shale and the ratio of the hydrocarbon generation potential value of a single layer of non-organic-rich shale to the average hydrocarbon generation potential value of a single layer of shale (hydrocarbon generation potential value of a single layer of non-organic-rich shale / average hydrocarbon generation potential value of a single layer of shale) as coordinate axes.

[0068] The above-mentioned set ratio is usually 38% to 42%; preferably, it is 40%.

[0069] Taking the setting ratio of 40% as an example, 40% of the average hydrocarbon generation potential value of all organic-rich shale monolayers in the quasi-in-situ conversion section is used as the lower limit of the hydrocarbon generation potential of the interlayer of the quasi-in-situ conversion section; then, through the above-mentioned thickness conversion, the lower limit of the monolayer thickness of the non-organic-rich shale monolayer as the interlayer of the quasi-in-situ conversion section is obtained.

[0070] 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 the worse the hydrocarbon generation potential is.

[0071] Embodiment 2

[0072] The second embodiment of the present invention provides a method for establishing a lithology identification model for an organic-rich shale development segment based on lithology binarization. Figure 2 As shown, the following steps are included:

[0073] Step S21: Determine the lower limit of the GR value of the organic-rich shale based on the binary lithology data of the core section of the target layer of the sample well.

[0074] 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.

[0075] Specifically, the binary lithology data of the coring section, including organic-rich shale and non-organic-rich shale (i.e., interlayer), is obtained by the following steps:

[0076] (1) Based on the thin section identification data of the core sampling 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, which includes mud shale.

[0077] The lithology description data in the core description data is only the lithology description made by geologists based on their experience of visual observation of the core. Due to the limitations of visual observation and the influence of subjective factors, the accuracy of the lithology description data needs to be further corrected. The thin section identification data can accurately realize the lithology naming, but the thin section identification data has limited sampling after all. Therefore, the lithology description data in the core description data is based on the verification of the thin section identification data to obtain preliminary lithology data.

[0078] 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.

[0079] (2) Based on the TOC detection data, the mudstone with a TOC value greater than the preset lower limit of the 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.

[0080] Thin section identification data can be used to accurately identify lithology at the millimeter level, but thin section identification data cannot distinguish whether mud shale is organic-rich shale or non-organic-rich shale. At this time, it is also necessary to refer to the TOC value, and mud shale with a TOC value not greater than the lower limit of the TOC of organic-rich shale, as well as other lithologies other than mud shale, are identified as non-organic-rich shale.

[0081] It can be seen that the organic-rich shale in this embodiment is defined based on the lower limit of TOC of organic-rich shale, and the shale that meets the 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.

[0082] 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.

[0083] Mud shale with a TOC value not greater than the lower limit of the TOC value of organic-rich shale, as well as other lithologies except mud shale, are identified as non-organic-rich shale.

[0084] Determining the lower limit of the GR value of organic-rich shale may include, based on the lithology data and the GR curve of the sample well, extracting the lithology and GR value of the sampling points with thin section identification data and TOC detection data; and obtaining the lower limit of the GR value of the organic-rich shale based on the lithology and GR values ​​of multiple sampling points.

[0085] 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 lithology data or binary lithology data of the coring section, the standardized well logging curve is depth-reset.

[0086] The GR values ​​of the above sampling points are extracted from the GR curve after standardization and depth return.

[0087] Step S22: taking the binary lithology data of the coring section and the curve section of the selected sensitive curve as a sample to establish a sample set.

[0088] In some embodiments, after obtaining the binary lithology data of the coring section, the method further includes screening the sensitivity curves of organic-rich shale and non-organic-rich shale from all types of logging curves of the sample well.

[0089] 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.

[0090] Embodiment 3

[0091] Embodiment 3 of the present invention provides a method for identifying interlayers in a heated rock mass in an in-situ conversion stage of shale oil, see Figure 3 As shown, the following steps are included:

[0092] Step S31: input the sensitivity curve of the target well in the shale layer into the lithology identification model, and obtain binary lithology data of the organic-rich shale development section including organic-rich shale and non-organic-rich shale according to the output result of the model.

[0093] The lithology identification model is pre-established in the manner described in the second embodiment above.

[0094] The working principle of the lithology identification model is to preliminarily locate the organic-rich shale development section based on the GR value lower limit of the organic-rich shale and the GR curve of the target well. According to the neural network learning results of the corresponding sensitive curve section of the organic-rich shale development section, its binary lithology data is determined to obtain the results for output.

[0095] 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 make a fine and high-resolution binary lithology prediction for the organic-rich shale development section.

[0096] In some embodiments, before inputting the sensitivity curve of the target well into the lithology identification model, the process further includes removing the high GR value abnormal values ​​of non-organic-rich shale from the sensitivity curve of the target well using the rock logging data. For example, the interference of special high GR rocks on the high GR response of organic-rich shale is removed, such as high uranium content sandstone.

[0097] Step S32: According to the set upper limit of the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithology data, at least one pseudo-in-situ conversion section is identified from the organic-rich shale development section.

[0098] That is, the identified simulated in-situ conversion section satisfies the requirement that the thickness of the non-organic-rich shale layer therein is less than the upper limit of the proportion of non-organic-rich shale in the in-situ conversion section.

[0099] The upper limit of the proportion of non-organic-rich shale in the in-situ conversion stage can usually be set to 20%. Optionally, it can also be set to other values ​​according to relevant regulations or actual research needs.

[0100] 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.

[0101] It can be that a bar graph of a binary lithology profile and a TOC profile of the organic-rich shale development section is established.

[0102] Furthermore, if there is coring data for the organic-rich shale development section of the target well, the lithology profile is established based on the binary lithology description data of the coring data; if the binary lithology description data in the coring data is incomplete, the lithology data is supplemented in combination with the model output results to establish a binary lithology profile.

[0103] The establishment of the TOC profile can be, if there are continuous measured TOC values ​​(sampling interval is not more than 0.5 meters) in the organic-rich shale development section of the target well, the TOC profile is established using the measured TOC values; 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 for the remaining parts to establish the TOC profile.

[0104] Specifically, the division of the heated rock mass in the proposed in-situ conversion stage is based on the following principles:

[0105] 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.

[0106] Furthermore, the first set difference includes the difference in overall TOC value and / or the difference in overall TOC curve morphology; the second set difference includes the difference in the number of non-organic-rich shale layers and / or the difference in the thickness of non-organic-rich shale layers.

[0107] 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 difference, or overall TOC value curve morphology difference. The specific difference needs to be determined in combination with actual conditions in different embodiments. Situation 2: there is no obvious TOC value curve characteristic difference between the heated rock mass and its adjacent heated rock mass, but there is an obvious lithologic combination difference, such as: the number of interlayers, or the difference in the thickness of a single interlayer, etc. The specific difference needs 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.

[0108] Step S34: Identify a single layer of non-organic-rich shale in the heated rock mass. If the thickness of the single layer of non-organic-rich shale is greater than the lower limit of the thickness of the single layer as an interlayer in the simulated in-situ conversion section, identify the single layer of non-organic-rich shale as an interlayer.

[0109] The lower limit of the single layer thickness is predetermined 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. The specific determination method is described in Example 1.

[0110] The third embodiment of the present application provides a method for identifying the interlayer of the heated rock mass in the in-situ conversion section of shale oil, wherein the working principle of the binary lithology interpretation method is: based on the fact that organic-rich shale is formed in a reducing environment that makes uranium elements easier to precipitate, resulting in the characteristics of high uranium and high natural gamma that are different from other lithologies, natural gamma is combined with conventional rock cuttings logging to eliminate the interference of other non-shale high GR rocks (such as sandstone-type uranium mines), and the vertical distribution of the high GR organic-rich shale development section is identified. In the identified organic-rich shale development section, by automatically calculating the correlation between various conventional logging curves and organic-rich shale, the curve with the best correlation is directly selected as the input curve, and the lithology identification model of organic-rich shale and non-organic-rich shale is automatically established by using a neural network method. The interpretation results are consistent with the actual results through continuous verification and iteration of the lithology identification model by the verification well. Finally, the front-end inputs various conventional logging curves, and the terminal automatically generates a high-precision lithology profile containing organic-rich shale and non-organic-rich shale.

[0111] The method for identifying the interlayer of the heated rock mass in the in-situ conversion section of shale oil provided in the third embodiment of the present invention, based on the binary lithology logging interpretation, identifies the quasi-in-situ conversion section according to the upper limit of the proportion of non-organic-rich shale in the in-situ conversion section; the quasi-in-situ conversion section is further subdivided into heated rock masses based on binary lithology differences and TOC differences, making it possible to adopt different well layout methods, heating schemes and subsequent oil and gas development schemes for heated rock masses with different geological and geochemical conditions, and providing an important geological evaluation means for the scale-effective development of in-situ conversion of shale oil. That is, the on-site significance of this achievement is to make it possible to design the in-situ conversion development scheme in a refined and differentiated manner.

[0112] The method for identifying the interlayers in 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 the interlayer of the proposed in-situ conversion section based on the average value of the hydrocarbon generation potential 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 it is determined that the thickness of the non-organic-rich shale single layer is greater than the lower limit of the single-layer thickness as the interlayer, it is determined to be an interlayer. First of all, this method is targeted at the specific application scenario of the organic-rich shale development section, breaking the limitation of the traditional identification of interlayers by relying solely on lithology, and is more suitable for geological evaluation and related research on the in-situ conversion of shale oil; 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 the interlayer of the proposed 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 thickness of the interlayer in this way 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 and the faster the deposition rate, the more difficult it is to enrich the organic matter, and the worse the hydrocarbon generation potential is.

[0113] The method for identifying interlayers in 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 thin interlayer lithology identification in the organic-rich shale development section. It abandons the universal pursuit of conventional well logging lithology interpretation to interpret and characterize various lithologies developed in the study area separately, and limits the lithology interpretation objects to two types: organic-rich shale and interlayers (non-organic-rich shale). It reduces the multi-solution of well logging lithology 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.

[0114] The method for identifying the heated rock interlayer in the in-situ conversion stage of shale oil provided in the third embodiment of the present invention only needs to use the core data of the sample well in the stage of establishing the lithology identification model. Once the modeling is completed, only conventional logging curves need to be used in the application stage to achieve high-precision characterization of the binary lithology of organic-rich shale. Under the premise of ensuring the accuracy of interpretation, the requirements for data quality are greatly reduced.

[0115] The method for identifying heated rock interlayers in the in-situ conversion stage of shale oil provided in Example 3 of the present invention adopts artificial intelligence methods such as neural networks to eliminate human influence as much as possible and further improve the reliability of lithology interpretation.

[0116] Embodiment 4

[0117] The fourth embodiment of the present invention provides a specific application of a method for dividing a heated rock mass in an in-situ conversion stage of shale oil, comprising the following steps:

[0118] S1: The shale oil in-situ conversion heating section in the sample well selected in the embodiment has continuous core samples, complete conventional logging curves, and systematic sampling and TOC testing have been carried out in the shale section, see Figure 4 shown.

[0119] S2: Standardize the logging curves of the sample wells. After lithology identification and TOC detection are carried out for the heated shale section, the lithology of the shale section is binarized into two categories: organic-rich shale and interlayer. The core and logging curve depth relocation, binary lithology sensitivity curve screening, and logging lithology identification model establishment are carried out in sequence. In this embodiment, the determined binary lithology sensitivity curves are natural gamma (GR), neutron compensation (CNL), and acoustic time difference (AC).

[0120] S3: A TOC logging interpretation model is established using the continuous TOC detection data (sampling interval is 0.1m-0.2m) of the organic-rich shale development section of the sample well, as well as the deep resistivity (RD), natural gamma (GR), and density (DEN) logging curve data.

[0121] S4: Using the lithology identification model and TOC logging interpretation model established in steps S2 and S3, a heated rock mass partitioning histogram including a binary lithology profile and a TOC profile is established, see Figure 4 shown.

[0122] S5: Determine the heating rock mass division scheme in combination with the bar graph established in step S4. In this embodiment, the shale oil in-situ conversion heating section is subdivided into three heating rock masses: T1, T2, and T3. The shale in the T1 section is pure, without interlayers, and has a high overall TOC; the T2 section has two sets of sand interlayers locally developed, and the TOC is relatively high overall; the T3 section has mixed shale and sandstone interlayers, with relatively developed sandstone interlayers, and the shale TOC is the lowest among the three, see Figure 5 shown.

[0123] Embodiment 5

[0124] Embodiment 5 of the present invention provides a specific application of a method for identifying a heated rock interlayer in a shale oil quasi-in-situ conversion section based on hydrocarbon generation potential, and identifies a sandstone interlayer from a shale quasi-in-situ conversion section, including the following steps:

[0125] S1: A well with continuous coring in an organic-rich shale interval was selected as a typical dissection well ( Figure 6 ).

[0126] S2: Based on the centimeter-level core description, the organic-rich shale section is divided into 10 sedimentary cycles. Each sedimentary cycle has a positive rhythm, that is, the bottom is a set of siltstone or silty mud shale, and the sediment grain size becomes finer and the lithology gradually changes to shale upward. In terms of sedimentary genesis, the siltstone or silty mud shale at the bottom of each cycle in this embodiment is a first-stage gravity flow deposit. According to the different ratios of the thickness of a single sedimentary cycle to the total thickness of the proposed heating section, this embodiment defines the four types of lithology combinations with ratios below 1%, 1% (inclusive) to 5% (inclusive), 5% to 10% (inclusive), and greater than 10% as Type I (0), Type II (1), Type III (4), and Type IV (5), as shown below. Figure 6 In this embodiment, lithologic combination sections No. 1, No. 5 and No. 9 are selected as sample collection sections.

[0127] S3: Select millimeter-scale core description and sample collection points for the type II, type III and type IV lithology combinations developed in this example ( Figure 6 ). The details are as follows: In the No. 1 lithologic combination section, select a sample collection point and code it as "sampling point 1" ( Figure 6 In the 5th and 9th lithologic combination sections, one sampling point was selected and named as “sampling point 2” ( Figure 6 2 in the figure) and "sampling point 3" ( Figure 6 Large thin sections were made for the samples collected from the three sampling points. The lithology of the three sampling points was described at the millimeter level with the help of the large thin sections. A total of 24 lithology single layers were divided at "sampling point 1" (as shown in Figure 3). Figure 7 shown), Figure 7 1-24 in the figure represent a single lithology layer, and 12 and 4 single lithology layers are divided in "sampling point 2" and "sampling point 3" respectively (e.g. Figure 8 As shown in the figure, the lithology single layer of "sampling point 2" includes ① to ③ of "sampling point 2-1", ① and ② of "sampling point 2-2", ① to ③ of "sampling point 2-3" and ① to ④ of "sampling point 2-4", a total of 12; the lithology single layer of "sampling point 3" includes ① to ④, a total of 4. In this embodiment, the lithology types of all lithology single layers include shale and silty interlayer.

[0128] S4: All monolayers are sampled using wire cutting technology. After each monolayer sample is prepared, a pyrolysis experiment is performed, and the sum of the pyrolysis free hydrocarbons S1 and the pyrolysis hydrocarbons S2 is taken as the hydrocarbon generation potential value of the monolayer.

[0129] S5: Count the hydrocarbon generation potential values ​​of the shale monolayers in all the monolayers and calculate their average value. 40% of the average value of the hydrocarbon generation potential values ​​of all the shale monolayers is taken as the lower limit of the hydrocarbon generation potential of the shale interlayer for in-situ conversion heating of shale oil. The remaining monolayers are regarded as silty sand interlayers.

[0130] S6: Put the ratio of the hydrocarbon generation potential of the 15 silty interlayers at the three sampling points to the average hydrocarbon generation potential of the shale single layer, and the thickness of each interlayer into the same coordinate system in the form of a scatter plot. Since the only lithology of the non-shale interlayer in this embodiment is the silty interlayer, only one scatter plot plate is needed. In this embodiment, the ordinate is the ratio of the hydrocarbon generation potential of the silty interlayer to the average hydrocarbon generation potential of the shale single layer, and the abscissa is the single layer thickness of each interlayer. Set a trend line of 15 data points, and take the thickness corresponding to the intersection of the trend line and the horizontal line with a ordinate value of 40% as the lower limit of the thickness of the low hydrocarbon generation potential interlayer. That is, in this embodiment, siltstone and silty mud shale with a single layer thickness not exceeding 10 mm are all considered to have a large hydrocarbon generation potential and are not considered as interlayers; siltstone and silty mud shale with a single layer thickness exceeding 10 mm are all considered as interlayers ( Fig. 9 ).

[0131] S7: For organic-rich shale sections, a multi-dimensional screening method of sensitive curves is used to select lithological sensitivity curves. Specifically, it includes: screening sample wells for selecting lithological sensitivity curves; relying on sample wells to carry out data preparation, including logging curve data and lithological data; establishing a logging lithology calibration plate containing standard lithology columns and all curves; using all logging curves of sample wells as candidates for lithological sensitivity curves to avoid missing sensitive curves, and statistically analyzing the value distribution range of each curve; setting a one-dimensional vertical axis for each curve, and arranging the axes corresponding to all curves horizontally; the top scale of all axes should be greater than the maximum value of the corresponding curve, and the bottom scale should be less than the minimum value of the corresponding curve, to ensure that the values ​​of all curves are distributed on the axis; unifying all axes Vertical length; connect the numerical projections of the same logging curve data collection point on each axis from left to right; the lithology of each logging curve data collection point is determined according to the logging lithology calibration plate; each lithology is marked with a unique color; connect the numerical projections of all logging curve data collection points on different logging curve axes one by one to form lithology distribution vein lines; statistically analyze the distribution patterns of different lithologies on each axis in the lithology sensitivity curve synchronous comparison screening coordinate system; the more convergent the vein lines of a certain lithology on a certain axis, and the more obvious the differentiation from the vein lines of other lithologies, the more sensitive the logging curve corresponding to the axis is to the lithology, and vice versa. After screening, GR, CNL and AC are determined to be the sensitive curves in this embodiment, such as Figure 5 shown.

[0132] S8: In the embodiment, the lithology interpretation sensitivity curves GR, CNL and AC are used as input curves to establish a logging lithology identification model based on the three sensitivity curves, and the interpretation model is further used to establish a lithology profile ( Fig.10 ).

[0133] S9: Identify and determine the interlayer of the shale section for in-situ conversion heating of shale oil according to the lower limit of the interlayer thickness described in step S6. Take the core section of "sampling point 1" in this embodiment as an example to reconstruct the lithology profile, and regard the silty interlayers with a thickness of less than 10 mm as shale. Finally, the lithology profile of the shale section for in-situ conversion of shale oil based on hydrocarbon generation potential is established, such as Fig.10 As shown. Fig.10 and Figure 6 The comparison shows that Figure 6 Many silty interlayers are Fig.10 This practice of ignoring lithologic interlayers is exactly what is needed for in-situ conversion of shale oil, because these ignored interlayers can also generate hydrocarbons without being considered as interlayers.

[0134] Based on the inventive concept of the present invention, an embodiment of the present invention further provides a shale oil in-situ conversion section heated rock interlayer identification device, the structure of the device is as follows: Fig.11 As shown, it includes a binary lithology prediction module 111, a heated rock mass division module 112, an interlayer identification module 113, a lithology identification model establishment module 114 and an interlayer single layer thickness lower limit determination module 115;

[0135] Binarization lithology prediction module 111 is used to input the sensitivity curve of the target well of the shale layer into the lithology identification model, and obtain binary lithology data of the organic-rich shale development section including organic-rich shale and non-organic-rich shale according to the model output result. The lithology identification model is pre-established by the lithology identification model establishment module 114;

[0136] A heated rock mass division module 112 is used to identify at least one quasi-in-situ conversion section from 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 lithology data, and 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;

[0137] The interlayer identification module 113 is used to identify the non-organic-rich shale monolayer in the heated rock mass. If the thickness of the non-organic-rich shale monolayer is greater than the lower limit of the monolayer thickness of the interlayer in the proposed in-situ conversion section, the non-organic-rich shale monolayer is identified as an interlayer. The lower limit of the monolayer thickness is predetermined by the interlayer monolayer thickness lower limit determination module 115 based on the average hydrocarbon generation potential value of the organic-rich shale monolayer in the shale layer and multiple data pairs including the thickness of the non-organic-rich shale monolayer and its hydrocarbon generation potential value.

[0138] In some embodiments, the lithology identification model building module 114 is used to pre-build the lithology identification model in the following manner:

[0139] The GR value lower limit of the organic-rich shale is determined according to the binary lithology data of the coring section of the target layer of the sample well; the binary lithology data of the coring section and the curve section of the selected sensitive curve are taken as a sample to establish a sample set; the selected neural network model is trained by using the sample set to establish a lithology recognition model, and the GR value lower limit is input into the lithology recognition model, and the GR value lower limit is used to locate the organic-rich shale development section.

[0140] In some embodiments, the heated rock mass division module 112 is used to divide the quasi-in-situ conversion section into at least one heated rock mass according to the following principles:

[0141] 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 with the adjacent heated rock mass meets the second set difference.

[0142] In some embodiments, the lithology identification model building module 114 is used to obtain the binary lithology data of the coring section of the target layer of the sample well in the following manner:

[0143] According to the thin section identification data of the coring 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, and the preliminary lithology data includes mud shale; according to the TOC detection data, the mud shale in the preliminary lithology data whose TOC value is greater than the preset organic-rich shale TOC lower limit is determined as organic-rich shale, and the binary lithology data of the coring section is obtained.

[0144] In some embodiments, the lithology identification model building module 114 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; according to the lithology and GR values ​​of multiple sampling points, the lower limit of the GR value of organic-rich shale is statistically obtained.

[0145] In some embodiments, the binary lithology prediction module 111 is further used to:

[0146] Using cuttings logging data, the sensitivity curves of the target wells were used to eliminate outliers with high GR values ​​in non-organic-rich shales.

[0147] In some embodiments, the interlayer single layer thickness lower limit determination module 115 is used to predetermine the single layer thickness lower limit of the interlayer to be used as the proposed in-situ conversion section in the following manner:

[0148] According to 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; according to 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 the 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 pseudo-in-situ conversion section.

[0149] In some embodiments, the interlayer single layer thickness lower limit determination module 115 is used to obtain 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 in the following manner:

[0150] According to the centimeter-level core description data of continuous coring sections in the shale layer, a quasi-in-situ conversion section is identified from the coring section, the identified quasi-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 the quasi-in-situ conversion section, and at least one unit of each type is screened; a millimeter-level binary lithological description is performed on the screened units, and the units are divided into multiple organic-rich shale monolayers and non-organic-rich shale monolayers according to the description results, rock samples are cut from the monolayers, and the hydrocarbon generation potential values ​​of the rock samples are determined through pyrolysis tests; and the average value of the hydrocarbon generation potential values ​​of the organic-rich shale monolayers and multiple data pairs including the thickness of the non-organic-rich shale monolayers and their hydrocarbon generation potential values ​​are statistically obtained.

[0151] In some embodiments, the interlayer single layer thickness lower limit determination module 115 is used to:

[0152] Each unit is classified into one of the following types:

[0153] 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%.

[0154] Regarding the device 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.

[0155] 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.

[0156] 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 executable 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.

[0157] Unless otherwise specifically stated, terms such as processing, computing, calculating, determining, displaying, etc. may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, which operate 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 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 mentioned throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0158] It should be understood that the specific order or hierarchy of steps in the disclosed process 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 protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0159] In the above 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 an embodiment of the claimed subject matter requires more features than those set forth in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, 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.

[0160] 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 can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0161] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a 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 can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0162] For software implementation, the techniques described in this application can be implemented with 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 outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0163] 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 should be recognized by those skilled in the art that the various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover 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 covered in a manner similar to the term "including", just as "including," explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to represent "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 method for identifying interlayers in heated rock mass in an in-situ conversion stage of shale oil, characterized in that: include: The sensitivity curve of the target well in the shale layer is input into the lithology identification model, and the binary lithology data of the organic-rich shale development section including organic-rich shale and non-organic-rich shale are obtained according to the output of the model; According to the set upper limit of the proportion of non-organic-rich shale in the in-situ conversion section and the binary lithology data, at least one pseudo-in-situ conversion section is identified from the organic-rich shale development section, and according to the distribution characteristics of the binary lithology and the TOC distribution characteristics, the pseudo-in-situ conversion section is divided into at least one heated rock mass; A non-organic-rich shale monolayer in a heated rock mass is identified. If the thickness of the non-organic-rich shale monolayer is greater than the lower limit of the monolayer thickness as an interlayer of a simulated in-situ conversion section, the non-organic-rich shale monolayer is identified as an interlayer. The lower limit of the monolayer thickness is predetermined based on an average value of the hydrocarbon generation potential of the organic-rich shale monolayer in the shale layer and a plurality of data pairs including the thickness of the non-organic-rich shale monolayer and its hydrocarbon generation potential.

2. The method according to claim 1, characterized in that The lithology identification model is pre-established in the following manner: According to the binary lithology data of the core section of the target layer in the sample well, the lower limit of the GR value of organic-rich shale is determined; The binary lithology data of the coring section and the curve section of the selected sensitive curve are taken as a sample to establish a sample set; The selected neural network model is trained using the sample set to establish a lithology identification model, and the GR value lower limit is input into the lithology 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 by the lithology identification model in the following way: Locating the organic-rich shale development section according to the GR value lower limit and the GR curve of the target well; According to the neural network learning result of the corresponding sensitive curve segment of the organic-rich shale development segment, the binary lithology data thereof is determined to obtain the result for output.

4. The method according to claim 2, characterized in that: The binary lithology 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 coring 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 lithology data is determined as organic-rich shale, and the binary lithology 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 lithology data and GR curve of the sample well, the lithology and GR value of the sampling point with thin section identification data and TOC detection data are extracted; According to 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 setting 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 proposed in-situ conversion section is predetermined by the following method: According to each of the data pairs, 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 value of the 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. According to 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 as the thickness of the non-organic-rich shale single layer corresponding to the set ratio, and the 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 pseudo-in-situ conversion section.

9. The method according to claim 2, characterized in that: The average value of hydrocarbon generation potential 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 are obtained by the following method: According to the binary lithology data of the core 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, the pseudo-in-situ conversion section is identified from the core 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 the pseudo-in-situ conversion section, and at least one unit is selected from each type of unit; Carry out millimeter-level binary lithology description on the selected units, divide the units into multiple organic-rich shale monolayers and non-organic-rich shale monolayers according to the description results, cut rock samples from the monolayers, and determine the hydrocarbon generation potential of the rock samples through pyrolysis tests; 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 obtained by statistics.

10. The method according to claim 9, characterized in that The type of each unit is determined according to the thickness ratio of the proposed in-situ conversion section, including: 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 any one of claims 1 to 10, characterized in that: The hydrocarbon generation potential value is the sum of free hydrocarbons S1 and pyrolysis hydrocarbons S2 per unit mass of rock.

12. The method according to any one of claims 1 to 10, characterized in that: Before inputting the sensitivity curve of the shale layer target well into the lithology identification model, the method further includes: Using cuttings logging data, the sensitivity curves of the target wells were used to eliminate outliers with high GR values ​​in non-organic-rich shales.

13. The method according to any one of claims 1 to 10, characterized in that: The upper limit of the proportion of non-organic-rich shale in the in-situ conversion stage is 20%.

14. A device for identifying interlayers in heated rock mass in an in-situ conversion section of shale oil, characterized in that: The device comprises a binary lithology prediction module, a heated rock mass division module, an interlayer identification module, a lithology identification model establishment module and an interlayer single layer thickness lower limit determination module; The binary lithology prediction module is used to input the sensitivity curve of the shale layer target well into the lithology identification model, and obtain the binary lithology data of the organic-rich shale development section including organic-rich shale and non-organic-rich shale according to the model output result. The lithology identification model is pre-established by the lithology identification model establishment module; The heated rock mass division module is used to identify at least one pseudo-in-situ conversion section from 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 lithology data, and divide the pseudo-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; The interlayer identification module is used to identify a single layer of non-organic-rich shale in the heated rock mass. If the thickness of the single layer of non-organic-rich shale is greater than the lower limit of the single layer thickness of the interlayer in the simulated in-situ conversion section, the single layer of non-organic-rich shale is identified as an interlayer. The lower limit of the single layer thickness is predetermined by the interlayer single layer thickness lower limit determination module based on the average hydrocarbon generation potential value of the single layer of organic-rich shale in the shale layer and a plurality of data pairs including the thickness of the single layer of non-organic-rich shale and its hydrocarbon generation potential value.

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

Images