A method and device for identifying interlayers in the in-situ conversion heating section of complex lithology shale oil

Abstract

The present invention discloses a method and device for identifying interlayers in the in-situ conversion heating section of complex lithologic shale oil, comprising the following steps: identifying non-shale layers based on the lithologic data of the proposed in-situ conversion section within the shale layer; identifying the non-shale layer as an interlayer if it is a single lithologic layer and its thickness is greater than the corresponding lower limit of the interlayer thickness; and determining whether the composite lithologic layer is an interlayer based on the thickness of each type of lithologic layer contained therein and the corresponding lower limit of the interlayer thickness. This method, targeted at specific application scenarios of organic-rich shale sections, breaks the limitations of traditional interlayer identification based solely on lithologic data, 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, reduces the data requirements, and enables interlayer identification with only lithologic data.

Description

Technical Field

[0001] The present invention relates to the technical field of geophysical logging and in-situ shale oil mining, and in particular to a method and device for identifying interlayers in an in-situ conversion heating section of shale oil with complex lithology. Background Art

[0002] Research indicates that my country's low- to medium-maturity shale oil resources hold enormous potential. Breakthroughs in exploration and development technologies will be of significant strategic significance for reducing my country's dependence on foreign crude oil. Currently, theoretical and technological exploration in this area is underway both domestically and internationally. The organic matter contained in low- and medium-maturity shales primarily consists of generated, retained oil and unconverted kerogen. Current unconventional oil and gas development methods, such as horizontal wells and large-scale hydraulic fracturing, are generally ineffective in extracting either type of organic matter. Production requires in-situ heating of the shale to convert the organic matter into more fluid, lighter oil and gas. This process requires detailed characterization of the organic-rich shale intervals to be heated, particularly identifying interlayers that influence heating and oil and gas conversion efficiency.

[0003] Currently, technical methods for evaluating interlayers in shale formations primarily focus on single lithologic interlayers. For example, they aim to identify and characterize non-shale interlayers such as sandstone, limestone, dolomite, and diamictite within shale. Within these classification schemes, studies have reported on the thickness, proportion, and development degree of individual interlayers (Zhu Deshun, Wang Yong, Zhu Deyan, et al. Definition criteria and key factors controlling the enrichment of interlayered shale oil in the first member of the Shahejie Formation in the Bonan Subsag, 2015; Cheng Ming, Luo Xiaorong, Lei Yuhong, et al. Distribution, fractal characteristics, and estimation methods of siltstone interlayers / laminae in the Zhangjiatan Shale of the Ordos Basin, 2015; Liu Yali, Liu Peng. Characteristics and role of interlayers in continental organic-rich mudstones: A case study of the Jiyang Depression, 2019; Wang Baohua, Li Hao, Lu Jianlin. Quantitative characterization of the development degree of non-mudstone interlayers in continental shale formations, 2019). In previous studies, the presence of interlayers primarily affected the accumulation, migration, and seepage of generated oil and gas, as well as the effectiveness of hydraulic fracturing during subsequent development. Therefore, current research on interlayers primarily focuses on their porosity, permeability, oil and gas saturation, and mechanical properties.

[0004] In terms of patented technologies, the evaluation of interlayers in shale formations often focuses on their impact on the seepage and content of generated oil and gas, as well as subsequent reservoir reconstruction. For example, there is a method for quantitatively characterizing the development of permeable interlayers in mudstone (authorized publication number: CN 110569512B), a classification of lithofacies associations in sandstone interlayer-developed sections in shale formations (application publication number: CN115876974A), a method and system for calculating the oil content index of sandstone interlayers in shale formations (application publication number: CN114894997A), and a method for evaluating the brittleness of continental shale gas reservoirs taking into account interlayer type (authorized publication number: CN115356772B). Summary of the Invention

[0005] The inventors discovered that for the in-situ conversion of shale oil, the target layer to be developed is the organic-rich shale section, and the target of exploitation is the immobile solid organic matter or the viscous retained oil that is difficult to flow. Traditional lithologic interlayer identification and evaluation has no significant benefit for the in-situ heating development of low-maturity shale oil. In contrast, accurately determining interlayers with poor hydrocarbon generation potential from the perspective of source rock quality is more practical for the efficient development of shale oil in situ conversion. Currently, there are few studies on the identification and evaluation of interlayers based on differences in hydrocarbon generation potential in organic-rich shale formations. In addition, due to the characteristics of most terrestrial shale formations such as rapid lithologic changes, a large number of interlayers, and thin single layer thickness, it is difficult to achieve high-precision evaluation of interlayers with low hydrocarbon generation potential in organic-rich shale formations.

[0006] 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 method and device for identifying interlayers in the heating section of complex lithology shale oil in situ conversion. The method and device can identify interlayers based on hydrocarbon generation potential, and provide important data basis for realizing efficient development of shale oil in situ conversion.

[0007] In a first aspect, an embodiment of the present invention provides a method for identifying interlayers in an in-situ conversion heating section of shale oil with complex lithology, comprising:

[0008] Identify non-shale layers based on lithologic data of the proposed in-situ conversion zone within the shale layer;

[0009] If the non-shale layer is a single lithologic layer, and the thickness of the non-shale layer is greater than the lower limit of the thickness of a single lithologic layer of the corresponding type as an interlayer in the simulated in-situ conversion section, the non-shale layer is identified as an interlayer;

[0010] If the non-shale layer is a composite lithologic layer, whether the composite lithologic layer is an interlayer is determined based on the thickness of each type of lithologic single layer contained in the composite lithologic layer and the lower limit of the single layer thickness of each type of lithologic single layer contained as an interlayer of the quasi-in-situ conversion section. The lower limit of the single layer thickness of each type of lithologic single layer contained as an interlayer of the quasi-in-situ conversion section is predetermined based on the average value of the hydrocarbon generation potential value of the shale single layer in the shale layer and multiple data pairs containing the thickness of the lithologic single layer of this type and its hydrocarbon generation potential value.

[0011] In a second aspect, an embodiment of the present invention provides an interlayer identification device for an in-situ conversion heating section of complex lithology shale oil, comprising a single layer thickness lower limit determination module for the interlayer, a non-shale layer identification module, and an interlayer identification module;

[0012] The interlayer single layer thickness lower limit determination module is used to predetermine the single layer thickness lower limit of each type of lithologic single layer as the interlayer of the simulated in-situ conversion section based on the average hydrocarbon generation potential value of the shale single layer in the shale layer and a plurality of data pairs containing the thickness of the lithologic single layer of this type and its hydrocarbon generation potential value;

[0013] The non-shale layer identification module is used to identify the non-shale layer based on the lithologic data of the simulated in-situ conversion heating section in the shale layer;

[0014] The interlayer identification module is used to identify the sandstone single layer as an interlayer if the non-shale layer is a single lithologic layer and the thickness of the non-shale layer is greater than the lower limit of the single layer thickness of the corresponding type of lithologic single layer as an interlayer of the pseudo-in-situ conversion section; if the non-shale layer is a composite lithologic layer, determine whether the composite lithologic layer is an interlayer based on the thickness of each type of lithologic single layer contained in the composite lithologic layer and the lower limit of the single layer thickness of each type of lithologic single layer contained as an interlayer of the pseudo-in-situ conversion section.

[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 above-mentioned method for identifying interlayers in the in-situ conversion heating section of complex lithology 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 above-mentioned method for identifying interlayers in the in-situ conversion heating section of complex lithology 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 method for identifying interlayers in the in-situ conversion heating section of complex lithologic shale oil provided in an embodiment of the present invention predetermines, for each type of lithology other than shale contained in a shale layer, the lower limit of the single-layer thickness of the lithologic single layer of the type as the interlayer of the quasi-in-situ conversion section based on the average value of the hydrocarbon generation potential value of the shale single layer in the shale layer and multiple data pairs containing the thickness of the lithologic single layer of the type and its hydrocarbon generation potential value; identifies non-shale layers based on the lithologic data of the quasi-in-situ conversion section in the shale layer, and determines whether the non-shale layer is an interlayer using different methods based on the thickness of the lithologic single layer and the corresponding lower limit of the single layer thickness as the interlayer, depending on whether the non-shale layer is a single lithologic layer or a composite lithologic layer. First, this method, specifically targeting organic-rich shale intervals, breaks the limitations of traditional lithologic identification of interlayers, making it more suitable for geological evaluation and related research on in-situ conversion of shale oil. Furthermore, this method converts the lower limit of the hydrocarbon generation potential of interlayers into a more intuitive and accessible lower limit of interlayer thickness, reducing data requirements. Only lithologic data is required to identify interlayers in shale oil proposed in-situ conversion. The direct reason for converting the lower limit of the hydrocarbon generation potential of interlayers into the lower limit of interlayer thickness in this way is that interlayer thickness has a relatively significant statistical relationship with the hydrocarbon generation potential of interlayers. The fundamental reason for this is that the enrichment of organic matter requires an extremely low sedimentation rate. The smaller the thickness of a single interlayer, the faster the sedimentation rate, the more difficult it is to enrich organic matter, and ultimately the lower the hydrocarbon generation potential.

[0019] (2) The method for identifying the interlayer of the in-situ conversion heating section of complex lithologic shale oil provided by the embodiment of the present invention relies on the data for determining the lower limit of the single layer thickness of each type of lithologic single layer as the interlayer of the pseudo-in-situ conversion section, which is the average value of the hydrocarbon generation potential value of the shale single layer in the shale layer and multiple data pairs containing the thickness of the lithologic single layer and its hydrocarbon generation potential value of each type of lithologic single layer. The data are obtained in the following way: based on the centimeter-level core description data of the continuous coring section in the shale layer and the upper limit of the proportion of non-shale layer in the in-situ conversion section, the pseudo-in-situ conversion is identified from the coring section. The proposed in-situ conversion section is divided into multiple units, and the type of each unit is determined by its thickness ratio to the proposed in-situ conversion section. At least one unit of each type is selected. The selected units are subjected to millimeter-level lithologic description. Based on the description results, the units are divided into multiple shale and sandstone single layers. Rock samples are cut from the single layers and their hydrocarbon generation potential values ​​are determined through pyrolysis testing. The average hydrocarbon generation potential value of the shale single layer is statistically obtained, and multiple data pairs containing the thickness of the lithologic single layer and its hydrocarbon generation potential value for each type of lithologic single layer are statistically obtained. Taking into full consideration the geological characteristics of shale formations, such as rapid lithologic changes and thin single layer thickness, through lithologic combination classification, multi-level core detailed description, and multi-scale sampling interval screening, the workload of basic research is significantly reduced while ensuring the lithologic representativeness and high sampling accuracy of the collected samples.

[0020] (3) The method for identifying interlayers in the in-situ conversion heating section of complex lithologic shale oil provided by the embodiment of the present invention is to cut rock samples from the unit, including: determining the reference plane direction according to the extension direction of the bedding plane of the screened unit, cutting and leveling the top and bottom surfaces of the unit in a direction parallel to the reference plane, cutting the side surfaces of the unit in a direction perpendicular to the reference plane so that the cross-section of the unit parallel to the reference plane has the same shape; cutting the unit into a first rock sample and a second rock sample in a direction perpendicular to the reference plane; obtaining an XRF scan of the cut surface of the second rock sample, obtaining a sequence of dividing lines arranged in an upper and lower order according to the data difference in the scan, and the dividing lines are consistent with the bedding plane direction at the corresponding position; cutting the first rock sample in sequence according to the dividing line sequence to obtain multiple rock samples. The continuous section preparation for the microscopic heterogeneity of fine-grained sedimentary rocks improves work efficiency and reduces sample loss rate; the dividing lines are consistent with the bedding plane direction at the corresponding position, the obtained rock samples are of full variety, have good heterogeneity representation, and are homogeneous, providing a basis for achieving fast and high-resolution sample property judgment.

[0021] 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.

[0022] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] 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:

[0024] Figure 1 This is a flow chart of a method for determining the lower limit of the thickness of each type of lithologic single layer as an interlayer in the simulated in-situ conversion section in Example 1 of the present invention;

[0025] Figure 2 This is a flow chart of the method for identifying interlayers in the heating section of in-situ conversion of complex lithology shale oil in Example 2 of the present invention;

[0026] Figure 3 This is a flow chart of the method for preparing a sample of an organic-rich shale section in Example 3 of the present invention;

[0027] Figure 4 This is an example diagram of a shale section with complex lithologic interlayers selected in Example 4 of the present invention;

[0028] Figure 5 This is a schematic structural diagram of the device for identifying the interlayer in the heating section of in-situ conversion of complex lithology shale oil in an embodiment of the present invention. DETAILED DESCRIPTION

[0029] 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.

[0030] 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.

[0031] 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.

[0032] Example 1

[0033] The first embodiment of the present invention provides a method for determining the lower limit of the thickness of each type of lithologic single layer as an interlayer in the pseudo-in-situ conversion section of a shale layer, specifically determining the lower limit of the thickness of the interlayer identified from the pseudo-in-situ conversion section, i.e., the organic-rich shale development section, in the shale layer. Each type of lithologic single layer here refers to a lithologic single layer of other lithologies contained in the shale layer except shale. Figure 1 As shown, the following steps are included:

[0034] Step S11: Based on the centimeter-level core description data of the continuous coring section in the shale layer and the upper limit of the non-shale layer ratio of the in-situ conversion section, identify the pseudo-in-situ conversion section from the coring 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 screen at least one unit from each type of unit.

[0035] First, typical dissected wells are selected to identify interlayers with low hydrocarbon generation potential. Generally, typical dissected wells must meet the following requirements:

[0036] (1) The dissecting well must be located within the shale oil in-situ conversion development block, or at least adjacent to the development block;

[0037] (2) at least one well;

[0038] (3) There is a continuous coring section in the shale oil in-situ conversion section where the shale is to be heated.

[0039] Based on the lithologic description data, the pseudo-in-situ conversion section, i.e., the organic-rich shale development section, was identified from the core sections sampled from typical dissecting wells.

[0040] In each identified pseudo-in-situ conversion section, the thickness ratio of the non-shale layer is less than the upper limit of the non-shale layer ratio.

[0041] The upper limit of the non-shale layer ratio 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.

[0042] 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.

[0043] Each unit is divided into one of the following types according to its thickness ratio to the proposed in-situ conversion section:

[0044] (1) The thickness ratio of the proposed in-situ conversion section is less than 1%,

[0045] (2) The thickness ratio of the proposed in-situ conversion section is not less than 1% and not more than 5%,

[0046] (3) The thickness ratio of the proposed in-situ conversion section is greater than 5% and not greater than 10%,

[0047] (4) The thickness ratio of the in-situ conversion section is greater than 10%.

[0048] 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.

[0049] 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.

[0050] Step S12: Conduct millimeter-level lithologic description on the screened units, divide the units into multiple lithologic single layers based on the description results, cut rock samples from the lithologic single layers, and determine the hydrocarbon generation potential of the rock samples through pyrolysis testing.

[0051] (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 by pyrolysis of the rock per unit mass) of each pyrolysis rock sample as the hydrocarbon generation potential value of the rock sample.

[0052] Optionally, multiple lithologic single-layer rock samples may be obtained by cutting from each unit (sampling layer segment), and the method in the following embodiment 3 may also be used.

[0053] Step S13: Statistically obtain the average value of the hydrocarbon generation potential of the shale single layer and a plurality of data pairs including the thickness of each type of lithologic single layer and its hydrocarbon generation potential value.

[0054] For each type of lithologic single layer, the following steps S14 and S15 are respectively performed to determine the lower limit of the thickness of the lithologic single layer of this type as the interlayer of the pseudo in-situ conversion section of the shale layer.

[0055] Step S14: For each type of lithologic single layer, multiple sample points are obtained based on the average hydrocarbon generation potential value of the shale single layer in the shale layer and multiple data pairs containing the thickness of the lithologic single layer of this type and its hydrocarbon generation potential value. Each sample point contains the ratio of the thickness and hydrocarbon generation potential value of the lithologic single layer of this type to the average hydrocarbon generation potential value of the shale single layer.

[0056] Step S15: Project the sample points into a coordinate system, obtain a fitting trend line by fitting, and determine the ratio of the hydrocarbon generation potential value to the average value of the hydrocarbon generation potential value of the shale single layer according to the fitting trend line as the single layer thickness corresponding to the set ratio. This thickness is determined as the lower limit of the single layer thickness of the lithologic single layer of this type as the interlayer of the simulated in-situ conversion section.

[0057] The above coordinate system uses the single layer thickness, the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the shale single layer (hydrocarbon generation potential value / average hydrocarbon generation potential value of the shale single layer) as the coordinate axis.

[0058] The above-mentioned set ratio is usually 38% to 42%; preferably, it is 40%.

[0059] Taking the set ratio of 40% as an example, 40% of the average hydrocarbon generation potential value of all 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, each type of lithologic single layer is obtained as the lower limit of the single layer thickness of the interlayer of the pseudo-in situ conversion section.

[0060] 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.

[0061] Example 2

[0062] The second embodiment of the present invention provides a method for identifying interlayers in the in-situ conversion heating section of complex lithology shale oil, which identifies interlayers from the pseudo in-situ conversion section in the shale layer, that is, the organic-rich shale development section. The process is as follows: Figure 2 As shown, the following steps are included:

[0063] Step S21: Identify a non-shale single layer based on the lithologic data of the proposed in-situ conversion section within the shale layer.

[0064] Lithologic data can be data obtained by interpreting conventional well logging curves, so its resolution can be consistent with the resolution of the well logging curves.

[0065] Step S22: If the non-shale layer is a single lithologic layer and the thickness of the non-shale layer is greater than the lower limit of the thickness of the corresponding lithologic layer as an interlayer in the simulated in-situ conversion section, the non-shale layer is identified as an interlayer.

[0066] If the thickness of a single lithologic layer other than shale is not greater than the lower limit of the thickness of a single lithologic layer of the corresponding type as the interlayer of the simulated in-situ conversion section, the non-shale layer is identified as a non-interlayer.

[0067] Step S23: If the non-shale layer is a composite lithologic layer, determine whether the composite lithologic layer is an interlayer based on the thickness of each type of lithologic single layer contained in the composite lithologic layer and the lower limit of the single layer thickness of each type of lithologic single layer contained as an interlayer in the simulated in-situ conversion section.

[0068] Specifically, it can be divided into the following two situations:

[0069] (1) If the thickness of any type of lithologic single layer contained in the composite lithologic layer is greater than the lower limit of the thickness of the lithologic single layer of that type as an interlayer of the simulated in-situ conversion section, the composite lithologic layer shall be identified as an interlayer.

[0070] If the thickness of any type of lithologic single layer is greater than the lower limit of the single layer thickness of the lithologic single layer of this type as an interlayer of the pseudo-in-situ conversion section, then this type of lithologic single layer can constitute an interlayer alone; and the composite lithologic layer also contains other non-shale lithologic single layers, so the composite lithologic layer can be identified as an interlayer.

[0071] (2) If the thickness of any type of lithologic single layer contained in the composite lithologic layer is not greater than the lower limit of the thickness of the lithologic single layer of that type as an interlayer of the pseudo-in-situ conversion section, determine the ratio of the thickness of each type of lithologic single layer contained in the composite lithologic layer to the lower limit of the thickness of the lithologic single layer of the corresponding type as an interlayer of the pseudo-in-situ conversion section. If the sum of the ratios is greater than 1, the composite lithologic layer is determined to be an interlayer.

[0072]

[0073] In the above formula, H is the thickness index of the composite lithology layer (i.e., the sum of the above ratios); n is the nth lithology single layer; hn is the thickness of the nth lithology single layer in the composite lithology layer; h0n is the lower limit of the interlayer thickness corresponding to the nth lithology in the composite lithology layer.

[0074] The lower limit of the single-layer thickness of each type of lithologic single layer as the interlayer of the quasi-in-situ conversion section is predetermined based on the average hydrocarbon generation potential value of the shale single layer in the shale layer and multiple data pairs containing the thickness of the lithologic single layer of this type and its hydrocarbon generation potential value. The specific determination method is described in the previous embodiment 1 and will not be repeated here.

[0075] The method for identifying interlayers in the in-situ conversion heating section of complex lithology shale oil provided in Example 2 of the present invention predetermines, for each type of lithology other than shale contained in the shale layer, the lower limit of the single-layer thickness of the lithology single layer of this type as the interlayer of the quasi-in-situ conversion section based on the average value of the hydrocarbon generation potential value of the shale single layer in the shale layer and multiple data pairs containing the thickness of the lithology single layer of this type and its hydrocarbon generation potential value; identifies non-shale layers based on the lithology data of the quasi-in-situ conversion section in the shale layer, and determines whether the non-shale layer is an interlayer using different methods based on the thickness of the lithology single layer and the corresponding lower limit of the single layer thickness as the interlayer, depending on whether the non-shale layer is a single lithology layer or a composite lithology layer. First, this method is targeted at specific application scenarios in organic-rich shale sections, breaking the limitations of traditional reliance on lithology to identify interlayers, making it 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 interlayers into a more intuitive and easier-to-obtain lower limit of interlayer thickness, reducing the data requirements. Only lithology data are needed to identify interlayers in shale oil sections to be converted in situ.

[0076] The second embodiment of the present invention provides a method for identifying interlayers in the in-situ conversion heating section of complex lithologic shale oil. The data relied upon for determining the lower limit of the single-layer thickness of each type of lithologic single layer as an interlayer of the quasi-in-situ conversion section are the average value of the hydrocarbon generation potential value of the shale single layer in the shale layer and multiple data pairs containing the thickness of the lithologic single layer and its hydrocarbon generation potential value for each type of lithologic single layer. The data are obtained in the following way: based on the centimeter-level core description data of the continuous coring section in the shale layer and the upper limit of the proportion of non-shale layers in the in-situ conversion section, the quasi-in-situ conversion section is identified from the coring section, and the identified The pseudo-in situ conversion section was divided into multiple units based on sedimentary cycles. The type of each unit was determined by its thickness ratio within 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, and based on the description results, the units were divided into multiple shale and sandstone monolayers. Rock samples were cut from the monolayers and their hydrocarbon generation potentials were determined through pyrolysis testing. The average hydrocarbon generation potential of the shale monolayers was statistically calculated, along with multiple data pairs containing the thickness of each lithologic monolayer and its hydrocarbon generation potential for each type of lithologic monolayer. Taking into full account the geological characteristics of shale formations, such as rapid lithologic changes and thin monolayer thickness, the lithologic combination classification, multi-level core detailed description, and multi-scale sampling interval screening significantly reduced the workload while ensuring the lithologic representativeness and high sampling accuracy of the collected samples.

[0077] Example 3

[0078] The third embodiment of the present invention provides a method for cutting and preparing a core unit sample of an organic-rich shale section, referring to Figure 3 As shown, the following steps are included:

[0079] Step S31: Determine the reference plane direction according to the extension direction of the bedding plane of the sample, cut the top and bottom surfaces of the sample parallel to the reference plane and make them flat, and cut the side surfaces of the sample perpendicular to the reference plane so that the shape of the cross section of the sample parallel to the reference plane is consistent.

[0080] The top and bottom surfaces of the sample are two end surfaces perpendicular to the axial direction of the coring section.

[0081] The reference plane is perpendicular to the dominant bedding plane and can be determined in one of the following two ways:

[0082] (1) Count the bedding plane directions of the samples and determine the direction with the most developed bedding planes as the reference plane direction.

[0083] (2) Based on the directions of the bedding planes of the samples, the reference plane direction is obtained by cluster analysis.

[0084] For example, the reference plane direction finally determined is the direction with the smallest sum of differences from each reference plane. The difference from each reference plane is determined respectively, and the direction with the smallest sum of differences is determined as the reference plane direction.

[0085] Taking the reference plane direction as P and the direction perpendicular to the reference plane as V as an example, the side of the sample is cut along the direction perpendicular to the reference plane so that the shape of the cross section of the sample parallel to the reference plane is consistent. It can be that the minimum cross-sectional area polygon of the sample parallel to P or any shape smaller than the minimum cross-sectional area polygon is used as the boundary, set as Z, and the sample polygon Z is cut along the vector V so that the cross-sectional area of ​​the sample along the direction of the vector P is equal.

[0086] Step S32: cutting the sample into a first rock sample and a second rock sample along a direction perpendicular to the reference plane.

[0087] Grind the cut section to make it level with a height difference of no more than 1mm.

[0088] The first rock sample is used as a scanning and reference rock sample, and the second rock sample is used as a cut rock sample, so the volume of the first rock sample does not need to be too large. Preferably, the volume ratio of the first rock sample to the second rock sample is greater than 10.

[0089] Step S33: Obtain an XRF scan of the cut surface of the second rock sample, and obtain a sequence of segmentation lines arranged in an upper and lower order based on data differences in the scan.

[0090] The second rock sample is placed in a Micro-XRF (micro-area X-ray fluorescence spectrometer) instrument, and the profile is adjusted to a horizontal state; the profile is scanned using Micro-XRF to generate an XRF scan image (data), which is a content distribution map of multiple set elements.

[0091] The XRF scanning conditions along vector V can be: a resolution of 5 microns, a scan width W of 1 to 2 cm (correspondingly, the width of the cut surface of the second rock sample is required to be 1 to 5 cm), and a scan length H, where H is the length of the sample within the range of the heterogeneity study, preferably 1 to 30 cm, and does not exceed HMax or the upper limit of the XRF scanner's sample chamber. HMax is the maximum height of the rock sample, which is the vertical distance between the top and bottom surfaces of the sample.

[0092] In some embodiments, obtaining the segmentation line sequence may include:

[0093] For each XRF scan image, points with a content change rate of the corresponding element higher than a set threshold are identified to obtain a scatter point set. Using the scatter point clustering analysis method, multiple possible segmentation lines are obtained from the scatter point set, and the two endpoints of each possible segmentation line are respectively on two opposite sides of the cut surface of the second rock sample; using the line clustering analysis method, the possible segmentation lines obtained from each XRF scan image are clustered and analyzed to obtain a segmentation line sequence arranged in upper and lower order.

[0094] The dividing line determined by the above method is a line formed by the points whose corresponding element content change rate is higher than the set threshold value in the horizontal matching position. Therefore, the dividing line is consistent with the direction of the bedding plane at the corresponding position; specifically, each dividing line is located on a bedding plane and is the line where the bedding plane intersects the cutting plane.

[0095] After obtaining the segmentation line sequence by the image method, the method may further include determining whether the distance between two adjacent segmentation lines is less than a set distance threshold; if so, deleting one of the segmentation lines, or merging two adjacent segmentation lines whose distance is less than the set distance threshold according to the merging rule of the cluster analysis similarity principle to obtain a new segmentation line.

[0096] The above-mentioned set distance threshold is usually set to 0.2 mm.

[0097] Step S34: cutting the first rock sample in sequence according to the segmentation line sequence to obtain a plurality of rock samples.

[0098] The first rock sample can be cut according to the cutting line sequence using a diamond wire cutting instrument.

[0099] Furthermore, since the dividing line is consistent with the direction of the bedding plane at the corresponding position, but not necessarily parallel to the reference plane, and the dividing lines are not necessarily parallel to each other, after completing the cutting of the first rock sample according to the dividing line sequence, the cut rock sample can be cut again according to the principle of maximum volume so that the top and bottom surfaces of the rock sample are parallel; optionally, if the rock property is only used to carry out rock pyrolysis testing, because the rock sample needs to be ground into powder, it is not necessary to level the top and bottom surfaces.

[0100] In the same vertical direction, multiple rock samples can be cut according to research needs. Therefore, in some embodiments, it can include determining at least one cutting direction perpendicular to the reference plane according to research needs, and completing vertical cutting of the first rock sample according to each cutting direction; wrapping the cut first rock sample with a set material (industrial wax can be used for wrapping), and cutting the wrapped first rock sample in sequence according to the dividing line sequence to obtain multiple rock samples.

[0101] Furthermore, the cut rock sample can be further cut according to the principle of maximizing the volume so that the top and bottom surfaces of the rock sample are parallel.

[0102] Finally, multiple shale and sandstone samples were obtained.

[0103] The sample preparation method provided in Example 3 of the present invention is aimed at the preparation of continuous slices of organic-rich shale sections, which improves work efficiency and reduces the sample loss rate; the dividing line is consistent with the direction of the bedding plane at the corresponding position, the prepared rock samples are of full variety, with good heterogeneity representation, and the rock samples are homogeneous bodies, providing a basis for achieving rapid and high-resolution sample property judgment.

[0104] Example 4

[0105] A fourth embodiment of the present invention provides a specific application of a method for identifying interlayers in an in-situ conversion heating section of complex lithology shale oil. The method includes identifying interlayers in a shale layer, i.e., an organic-rich shale section, which is a simulated in-situ conversion section, and includes the following steps:

[0106] S1: The typical dissected well selected in the embodiment is located in the mixed shale development area, and the organic-rich shale section is continuously cored. The 10.3m coring section from 3185.3m to 3195.6m is selected for the demonstration of this embodiment ( Figure 4 ).

[0107] S2: After centimeter-level core description, the coring section in the embodiment is divided into four lithologic combination sections according to lithologic differences. The first lithologic combination section is a mixed shale section, which is composed of shale and various non-shale lithologic interlayers; the second lithologic combination section is a dolomitic shale section, which is mainly composed of dolomitic interlayers and shale; the third lithologic combination section is a sandy shale section, which is mainly composed of sandstone interlayers and shale of different particle sizes and sand content; the fourth lithologic combination section is a limestone shale section, which is mainly composed of limestone interlayers and shale ( Figure 4 ). In this embodiment, the first lithologic combination section is selected as the sample collection section.

[0108] S3: Millimeter-scale core description of the first lithologic combination section. The results show that there are 11 single layers and 9 lithologies constituting the non-shale interlayer. The specific lithologies are as follows: Figure 4 shown.

[0109] S4: Cut and sample the various non-shale interlayers and shale layers in the first lithologic combination section, and conduct analysis and testing on each layer to determine the hydrocarbon generation potential.

[0110] S5: Calculate the average hydrocarbon generation potential value of all shale single layers in the sampling interval. In this embodiment, 40% of the average hydrocarbon generation potential value of all shale single layers in the shale interval to be heated is used as the lower limit of the hydrocarbon generation potential of the interlayer of the shale interval to be heated by in-situ conversion of shale oil.

[0111] S6: There are 4 points that require special attention in this step: (1) The percentage of hydrocarbon generation potential value of each of the 9 lithologic layers in the non-shale interlayer to the average hydrocarbon generation potential value of the shale layer should be counted. The statistical scope includes the entire typical dissected well, that is, the same lithologic layers in other lithologic combination sections with millimeter-level core description are also counted. For each lithologic layer, a relationship chart of the percentage of hydrocarbon generation potential value of each lithologic layer to the average hydrocarbon generation potential value of the shale layer and the thickness of the layer is established; (2) When determining the thickness of the non-shale interlayer layer, since there is no shale layer separating the various non-shale interlayer layers in the first lithologic combination section, this 11-layer ( Figure 4(1-11) The combined sections composed of 9 lithologies are merged into a single layer, namely a "merged single layer"; (3) When the thickness of any single layer in the 11 single layers exceeds the upper limit of the hydrocarbon generation potential interlayer thickness of its corresponding lithology, regardless of the thickness of other lithology single layers, the entire "merged single layer" is considered to be a low hydrocarbon generation potential interlayer; (4) When all 11 single layers exceed the upper limit of the low hydrocarbon generation potential interlayer thickness of their corresponding lithology, and the "merged single layer thickness index (H)" of the entire "merged single layer" reaches or exceeds 1, the entire "merged single layer" is considered to be a low hydrocarbon generation potential interlayer, otherwise, the "merged single layer" is considered to be an in-situ converted shale section.

[0112] Based on the inventive concept of the present invention, the embodiment of the present invention also provides a device for identifying the interlayer of the in-situ conversion heating section of complex lithology shale oil. The structure of the device is as follows: Figure 5 As shown, it includes a single layer thickness lower limit determination module 51 for interlayers, a non-shale layer identification module 52 and an interlayer identification module 53;

[0113] The interlayer single layer thickness lower limit determination module 51 is used to predetermine the single layer thickness lower limit of each type of lithologic single layer as the interlayer of the proposed in-situ conversion section based on the average hydrocarbon generation potential value of the shale single layer in the shale layer and a plurality of data pairs including the thickness of the lithologic single layer of the type and its hydrocarbon generation potential value;

[0114] The non-shale layer identification module 52 is used to identify the non-shale layer based on the lithologic data of the proposed in-situ conversion heating section in the shale layer;

[0115] The interlayer identification module 53 is used to identify the sandstone single layer as an interlayer if the non-shale layer is a single lithologic layer and the thickness of the non-shale layer is greater than the lower limit of the single layer thickness of the corresponding type of lithologic single layer as an interlayer of the pseudo-in-situ conversion section; if the non-shale layer is a composite lithologic layer, determine whether the composite lithologic layer is an interlayer based on the thickness of each type of lithologic single layer contained in the composite lithologic layer and the lower limit of the single layer thickness of each type of lithologic single layer contained as an interlayer of the pseudo-in-situ conversion section.

[0116] In some embodiments, the interlayer identification module 53 is configured to:

[0117] If the thickness of any type of lithologic single layer contained in the composite lithologic layer is greater than the lower limit of the single layer thickness of the lithologic single layer of the type serving as an interlayer of the pseudo-in-situ conversion section, the composite lithologic layer is identified as an interlayer; otherwise, the ratio of the thickness of each type of lithologic single layer contained in the composite lithologic layer to the lower limit of the single layer thickness of the corresponding type of lithologic single layer serving as an interlayer of the pseudo-in-situ conversion section is determined; if the sum of the ratios is greater than 1, the composite lithologic layer is determined to be an interlayer.

[0118] In some embodiments, the interlayer single layer thickness lower limit determination module 51 is used to predetermine the single layer thickness lower limit of each type of lithologic single layer as the interlayer of the simulated in-situ conversion section in the following manner:

[0119] For each type of lithologic single layer, multiple sample points are obtained based on the average hydrocarbon generation potential value of the shale single layer in the shale layer and multiple data pairs containing the thickness of the lithologic single layer of this type and its hydrocarbon generation potential value. Each sample point contains the thickness of the lithologic single layer of this type and the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the shale single layer. The sample points are projected into a coordinate system to obtain a fitting trend line. According to the fitting trend line, the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the shale single layer is determined to be the single layer thickness corresponding to the set ratio. This thickness is determined as the lower limit of the single layer thickness of the lithologic single layer of this type as the interlayer of the pseudo-in-situ conversion section.

[0120] In some embodiments, the interlayer single layer thickness lower limit determination module 51 is configured to obtain an average hydrocarbon generation potential value of a shale single layer in the shale layer and a plurality of data pairs including the thickness of each lithologic single layer and its hydrocarbon generation potential value for each type of lithologic single layer in the following manner:

[0121] Based on centimeter-level core description data of continuous coring sections within a shale layer and an upper limit on the proportion of non-shale layers in an in-situ conversion section, a 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 sedimentary cycles, the type of each unit is determined according to the thickness ratio of the pseudo-in-situ conversion section in which it is located, and at least one unit of each type of unit is screened; a millimeter-level lithologic description is performed on the screened units, and based on the description results, the units are divided into multiple lithologic single layers, rock samples are cut from the lithologic single layers, and the hydrocarbon generation potential of the rock samples is determined through pyrolysis testing; and the average hydrocarbon generation potential of the shale single layers and multiple data pairs containing the thickness of the lithologic single layer and its hydrocarbon generation potential value for each type of lithologic single layer are statistically obtained.

[0122] In some embodiments, the interlayer single layer thickness lower limit determination module 51 is used to classify the type of each unit into one of the following types:

[0123] 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%.

[0124] 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.

[0125] 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 interlayers in the in-situ conversion heating section of complex lithology shale oil is implemented.

[0126] 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 interlayers in the in-situ conversion heating section of complex lithology shale oil is implemented.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] 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 method for identifying interlayers in the in-situ conversion heating section of complex lithology shale oil, characterized by: include: Identify non-shale layers based on lithologic data of the proposed in-situ conversion zone within the shale layer; If the non-shale layer is a single lithologic layer, and the thickness of the non-shale layer is greater than the lower limit of the thickness of a single lithologic layer of the corresponding type as an interlayer in the simulated in-situ conversion section, the non-shale layer is identified as an interlayer; If the non-shale layer is a composite lithologic layer, whether the composite lithologic layer is an interlayer is determined based on the thickness of each type of lithologic single layer contained in the composite lithologic layer and the lower limit of the thickness of each type of lithologic single layer as an interlayer in the pseudo-in-situ conversion section. The lower limit of the thickness of each type of lithologic single layer as an interlayer in the pseudo-in-situ conversion section is predetermined in the following manner: for each type of lithologic single layer, multiple sample points are obtained based on the average hydrocarbon generation potential value of the shale single layers in the shale layer and multiple data pairs containing the thickness of each type of lithologic single layer and its hydrocarbon generation potential value, each sample point containing the thickness of the lithologic single layer of the type and the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the shale single layer; the sample points are projected into a coordinate system to obtain a fitted trend line; based on the fitted trend line, the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the shale single layer is determined to be the single layer thickness corresponding to the set ratio; and this thickness is determined as the lower limit of the thickness of the lithologic single layer of the type as an interlayer in the pseudo-in-situ conversion section.

2. The method according to claim 1, characterized in that Determining whether the composite lithologic layer is an interlayer according to the thickness of each type of lithologic single layer contained in the composite lithologic layer and the lower limit of the thickness of each type of lithologic single layer as an interlayer of the pseudo in-situ conversion section includes: If the thickness of any type of lithologic single layer contained in the composite lithologic layer is greater than the lower limit of the thickness of the lithologic single layer of the type as an interlayer of the pseudo in-situ conversion section, the composite lithologic layer is identified as an interlayer; Otherwise, determine the ratio of the thickness of each type of lithologic single layer contained in the composite lithologic layer to the lower limit of the single layer thickness of the corresponding type of lithologic single layer as the interlayer of the pseudo-in-situ conversion section. If the sum of the ratios is greater than 1, determine that the composite lithologic layer is an interlayer.

3. The method according to claim 1, characterized in that The set ratio is 38% to 42%.

4. The method according to claim 1, wherein The average value of the hydrocarbon generation potential of the shale single layer in the shale layer and a plurality of data pairs including the thickness of each type of lithologic single layer and its hydrocarbon generation potential value are obtained by the following method: Based on centimeter-level core description data of continuous coring sections within the shale layer and an upper limit of the proportion of non-shale layers in the in-situ conversion section, identifying a pseudo-in-situ conversion section from the coring section, dividing the identified pseudo-in-situ conversion section into multiple units according to sedimentary cycles, determining the type of each unit based on its thickness ratio to the pseudo-in-situ conversion section, and selecting at least one unit from each type of unit; Conduct millimeter-level lithologic descriptions on the selected units. Based on the description results, the units are divided into multiple lithologic layers. Rock samples are cut from the lithologic layers and their hydrocarbon generation potential is determined through pyrolysis testing. The average value of the hydrocarbon generation potential value of the shale single layer and multiple data pairs including the thickness of the lithologic single layer and its hydrocarbon generation potential value for each type of lithologic single layer are statistically obtained.

5. The method according to claim 4, 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%.

6. The method according to claim 4, characterized in that The process of performing millimeter-level lithologic description on the screened units, dividing the units into multiple lithologic single layers based on the description results, and cutting rock samples from the lithologic single layers further includes: Determine the reference plane direction according to the extension direction of the bedding plane of the screened unit, cut and level the top and bottom surfaces of the unit in a direction parallel to the reference plane, and cut the side surfaces of the unit in a direction perpendicular to the reference plane so that the cross-sections of the unit parallel to the reference plane have the same shape; cutting the unit into a first rock sample and a second rock sample along a direction perpendicular to the reference plane; Obtaining an XRF scan of the cut surface of the second rock sample, and obtaining a sequence of segmentation lines arranged in a vertical order based on data differences in the scan, wherein the segmentation lines are consistent in direction with bedding planes at corresponding positions; The first rock sample is cut in sequence according to the segmentation line sequence to obtain a plurality of rock samples.

7. The method according to claim 6, characterized in that The XRF scans are multiple distribution maps of the content of set elements. The sequence of dividing lines arranged in a vertical order is obtained based on the data differences in the scans, including: For each XRF scan image, points where the content change rate of the corresponding element is higher than a set threshold are identified to obtain a scatter point set. A scatter point cluster analysis method is used to obtain multiple possible segmentation lines from the scatter point set, where the two endpoints of each possible segmentation line are respectively on two opposite sides of the cut surface of the second rock sample; The possible segmentation lines obtained from each XRF scan image are clustered and analyzed by a line clustering analysis method to obtain a segmentation line sequence arranged in an upper and lower order.

8. The method according to claim 7, characterized in that Also includes: Determine whether the distance between two adjacent segmentation lines is less than the set distance threshold; If so, delete one of the segmentation lines, or merge two adjacent segmentation lines whose distance is less than the set distance threshold according to the merging rule of the cluster analysis similarity principle to obtain a new segmentation line.

9. The method according to claim 1, characterized in that The hydrocarbon generation potential value is the sum of free hydrocarbon S1 and pyrolysis hydrocarbon S2 per unit mass of rock.

10. A device for identifying interlayers in the in-situ conversion heating section of complex lithology shale oil, characterized in that: The device includes a single layer thickness lower limit determination module for the interlayer, a non-shale layer identification module, and an interlayer identification module; The interlayer single layer thickness lower limit determination module is used to determine, for each type of lithologic single layer, in advance the single layer thickness lower limit of each type of lithologic single layer as an interlayer in the pseudo-in-situ conversion section in the following manner: based on the average hydrocarbon generation potential value of the shale single layer in the shale layer and a plurality of data pairs including the thickness of the lithologic single layer of this type and its hydrocarbon generation potential value, obtain a plurality of sample points, each sample point including the thickness of the lithologic single layer of this type and the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the shale single layer; project the sample points into a coordinate system to obtain a fitting trend line; determine, based on the fitting trend line, the ratio of the hydrocarbon generation potential value to the average hydrocarbon generation potential value of the shale single layer as the single layer thickness corresponding to the set ratio; and determine the thickness as the single layer thickness lower limit of the lithologic single layer of this type as the interlayer in the pseudo-in-situ conversion section; The non-shale layer identification module is used to identify the non-shale layer based on the lithologic data of the simulated in-situ conversion heating section in the shale layer; The interlayer identification module is used to identify the non-shale layer as an interlayer if the non-shale layer is a single lithologic layer and the thickness of the non-shale layer is greater than the lower limit of the single layer thickness of the corresponding type of lithologic single layer as an interlayer of the pseudo-in-situ conversion section; if the non-shale layer is a composite lithologic layer, determine whether the composite lithologic layer is an interlayer based on the thickness of each type of lithologic single layer contained in the composite lithologic layer and the lower limit of the single layer thickness of each type of lithologic single layer contained as an interlayer of the pseudo-in-situ conversion section.

11. 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 interlayers in the in-situ conversion heating section of complex lithology shale oil according to any one of claims 1 to 9.

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