Shale oiliness grade determination method and device, equipment and storage medium

Abstract

The embodiment of the invention provides a shale oiliness grade determination method and device, equipment and a storage medium. The method comprises the following steps: acquiring a shale sample set on a target region; wherein the shale sample set comprises a plurality of shale samples, and the shale samples have free hydrocarbon content and total organic carbon content; generating an outer envelope line according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set; wherein the outer envelope line surrounds the shale samples in the shale sample set; according to the outer envelope line, determining a region surrounded by the outer envelope line as a plurality of sub-regions; wherein the sub-regions have corresponding shale oiliness grades; the shale oiliness grade of the shale sample falling into the sub-region is the shale oiliness grade corresponding to the sub-region. The method is used for achieving the effect of improving the accuracy of determining the shale oiliness grade of the shale sample.

Description

Technical Field

[0001] The present application relates to the field of energy exploration, and in particular to a method, device, equipment and storage medium for determining the oil content grade of shale. Background Art

[0002] The field of energy exploration and development includes the development of conventional oil and gas and the development of unconventional oil and gas. The development of unconventional oil and gas can include the development of continental shale oil. The evaluation of shale oil content grade is the basis for the development of continental shale oil.

[0003] In some technologies, a shale sample can be excited by a laser light source to measure the oil content of the shale sample, thereby determining the shale oil content grade of the shale sample.

[0004] However, the above-mentioned method of only measuring cannot accurately determine the oil content of the shale sample, and cannot accurately determine the shale oil content grade of the shale sample. Summary of the invention

[0005] The embodiments of the present application provide a method, device, equipment and storage medium for determining the oil content grade of shale, so as to achieve the effect of improving the accuracy of determining the oil content grade of shale samples.

[0006] In a first aspect, an embodiment of the present application provides a method for determining the oil content grade of shale, comprising:

[0007] Acquire a shale sample set in a target area; wherein the shale sample set includes a plurality of shale samples, and the shale samples have free hydrocarbon content and total organic carbon content;

[0008] generating an outer envelope according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set; wherein the outer envelope surrounds the shale samples in the shale sample set;

[0009] According to the outer envelope, the area surrounded by the outer envelope is determined as a plurality of sub-areas; wherein the sub-areas have corresponding shale oil content grades;

[0010] The shale oil content grade of the shale samples falling into the sub-region is the shale oil content grade corresponding to the sub-region.

[0011] In a possible implementation, generating an outer envelope according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set includes:

[0012] A coordinate system is established with the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis;

[0013] Determine the shale sample to be processed that has the largest free hydrocarbon content when the total organic carbon content has the same value;

[0014] Obtaining each processed shale sample from discrete samples of the shale samples to be processed with the largest value of each free hydrocarbon content;

[0015] The outer envelope was obtained by fitting the shale samples after each treatment.

[0016] In a possible implementation, according to the outer envelope, the area surrounded by the outer envelope is determined as a plurality of sub-areas, including:

[0017] Generate a preset straight line; wherein the slope value of the preset straight line is a preset value, the preset straight line takes the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis; the preset straight line passes through the origin of the coordinate system where the outer envelope line is located;

[0018] According to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas.

[0019] In a possible implementation, according to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas, including:

[0020] Determine the intersection point between the preset straight line and the outer envelope line as the first intersection point;

[0021] A first perpendicular line is obtained by drawing a perpendicular line from the first intersection point to the horizontal axis of the coordinate system, and a second perpendicular line is obtained by drawing a perpendicular line from the first intersection point to the vertical axis of the coordinate system;

[0022] Determine the intersection point between the second perpendicular line and the outer envelope line as the second intersection point; and draw a perpendicular line from the second intersection point to the horizontal axis of the coordinate system to obtain a third perpendicular line;

[0023] A plurality of sub-areas are determined according to the outer envelope, the first vertical line, the second vertical line, and the third vertical line.

[0024] In a possible implementation, a plurality of sub-areas are determined according to the outer envelope, the first vertical line, the second vertical line, and the third vertical line, including:

[0025] Determine an area enclosed by the outer envelope and the second perpendicular line as a first sub-area among the sub-areas;

[0026] Determine an area enclosed by the second vertical line, the preset straight line, and the third vertical line as a second sub-area in the multiple sub-areas;

[0027] Determine an area enclosed by the first vertical line, the preset straight line, and the third vertical line as a third sub-area among the multiple sub-areas;

[0028] It is determined that the area surrounded by the outer envelope, excluding the first sub-area, the second sub-area, and the third sub-area, is the fourth sub-area among the plurality of sub-areas.

[0029] In a possible implementation, obtaining a shale sample set in a target area includes:

[0030] The shale samples are measured and analyzed by a rock pyrolysis instrument to obtain the free hydrocarbon content of the shale samples;

[0031] The shale samples are measured and analyzed by a total organic carbon analyzer to obtain the total organic carbon content of the shale samples.

[0032] In a second aspect, an embodiment of the present application provides a device for determining the oil content grade of shale, comprising:

[0033] An acquisition module is used to acquire a shale sample set in a target area; wherein the shale sample set includes a plurality of shale samples, and the shale samples have a free hydrocarbon content and a total organic carbon content;

[0034] A processing module, configured to generate an outer envelope according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set; wherein the outer envelope surrounds the shale samples in the shale sample set;

[0035] The processing module is further used to determine the area surrounded by the outer envelope line into multiple sub-areas according to the outer envelope line; wherein the sub-areas have corresponding shale oil content grades;

[0036] The processing module is also used to determine the shale oil content grade of the shale samples falling into the sub-region as the shale oil content grade corresponding to the sub-region.

[0037] In a possible implementation, an outer envelope is generated according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set, and the processing module is used to:

[0038] A coordinate system is established with the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis;

[0039] Determine the shale sample to be processed that has the largest free hydrocarbon content when the total organic carbon content has the same value;

[0040] Obtaining each processed shale sample from discrete samples of the shale samples to be processed with the largest value of each free hydrocarbon content;

[0041] The outer envelope was obtained by fitting the shale samples after each treatment.

[0042] In a possible implementation, according to the outer envelope, the area surrounded by the outer envelope is determined as a plurality of sub-areas, and the processing module is used to:

[0043] Generate a preset straight line; wherein the slope value of the preset straight line is a preset value, the preset straight line takes the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis; the preset straight line passes through the origin of the coordinate system where the outer envelope line is located;

[0044] According to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas.

[0045] In a possible implementation, according to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas, and the processing module is used to:

[0046] Determine the intersection point between the preset straight line and the outer envelope line as the first intersection point;

[0047] A first perpendicular line is obtained by drawing a perpendicular line from the first intersection point to the horizontal axis of the coordinate system, and a second perpendicular line is obtained by drawing a perpendicular line from the first intersection point to the vertical axis of the coordinate system;

[0048] Determine the intersection point between the second perpendicular line and the outer envelope line as the second intersection point; and draw a perpendicular line from the second intersection point to the horizontal axis of the coordinate system to obtain a third perpendicular line;

[0049] A plurality of sub-areas are determined according to the outer envelope, the first vertical line, the second vertical line, and the third vertical line.

[0050] In a possible implementation, a plurality of sub-areas are determined according to the outer envelope, the first vertical line, the second vertical line, and the third vertical line, and the processing module is used to:

[0051] Determine an area enclosed by the outer envelope and the second perpendicular line as a first sub-area among the sub-areas;

[0052] Determine an area enclosed by the second vertical line, the preset straight line, and the third vertical line as a second sub-area in the multiple sub-areas;

[0053] Determine an area enclosed by the first vertical line, the preset straight line, and the third vertical line as a third sub-area among the multiple sub-areas;

[0054] It is determined that the area surrounded by the outer envelope, excluding the first sub-area, the second sub-area, and the third sub-area, is the fourth sub-area among the plurality of sub-areas.

[0055] In a possible implementation, a shale sample set in a target area is obtained, and the obtaining module is used to:

[0056] The shale samples are measured and analyzed by a rock pyrolysis instrument to obtain the free hydrocarbon content of the shale samples;

[0057] The shale samples are measured and analyzed by a total organic carbon analyzer to obtain the total organic carbon content of the shale samples.

[0058] In a third aspect, an embodiment of the present application provides an electronic device, including: a memory, a processor;

[0059] Memory stores computer-executable instructions;

[0060] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementations of the first aspect.

[0061] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the first aspect above and / or various possible implementations of the first aspect.

[0062] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the above first aspect and / or various possible implementation methods of the first aspect.

[0063] The method, device, equipment and storage medium for determining the shale oil content grade provided in the embodiments of the present application obtain multiple shale samples in the target area, and measure and analyze the shale samples to obtain the total organic carbon content and the free hydrocarbon content. According to the total organic carbon content and free hydrocarbon content of the multiple shale samples, an outer envelope is determined in the coordinate system, and the area surrounded by the outer envelope is divided into sub-areas. According to which sub-area the total organic carbon content and free hydrocarbon content of the shale sample fall in the coordinate system, the shale oil content grade of the shale sample is determined as the shale oil content grade corresponding to the sub-area. Thereby achieving the effect of improving the accuracy of determining the shale oil content grade of the shale sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0065] Figure 1 Schematic diagram of the process of determining the shale oil content grade provided in this application Figure 1 ;

[0066] Figure 2 Schematic diagram of the process of determining the shale oil content grade provided in this application Figure 2 ;

[0067] Figure 3 is a schematic diagram of the outer envelope in an exemplary coordinate system;

[0068] Figure 4 Schematic diagram of the process of determining the shale oil content grade provided in this application Figure 3 ;

[0069] Figure 5 is a schematic diagram of the division of exemplary sub-regions;

[0070] Figure 6 A schematic diagram of shale oil content grades for exemplary shale samples;

[0071] Figure 7 The results of shale oil content evaluation at different depths of the target single well are shown in the figure;

[0072] Figure 8 A schematic diagram of the structure of a device for determining the oil content grade of shale provided in this application;

[0073] Fig. 9 A schematic diagram of the structure of the electronic device provided in this application.

[0074] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0075] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0076] First, the terms involved in this application are explained:

[0077] Free hydrocarbon content (S1) refers to the content of hydrocarbon gas or liquid that has been generated in the shale sample but has not yet been migrated out and has not been adsorbed by the primary pores in the shale sample, and still remains.

[0078] Total Organic Carbon (TOC): refers to the total amount of organic carbon elements in water or organic matter. By measuring the total organic carbon content in shale samples, the oil generation potential of shale can be further determined.

[0079] Oil Saturation Index (OSI): refers to an important parameter used to evaluate the performance of shale oil reservoirs. OSI can be obtained by multiplying the ratio of S1 in the shale sample to TOC in the shale sample by 100. OSI can indirectly reflect the generation and enrichment of hydrocarbons in the shale sample. When the OSI value is high, it means that the shale is rich in hydrocarbons, which is sufficient to meet the adsorption and filling of the reservoir space inside the shale sample; otherwise, it indicates that the hydrocarbon content is relatively low and the reservoir space of the shale sample may not be fully utilized. Optionally, when the OSI value is greater than 100 mg / g, it is considered that the hydrocarbons already generated in the shale formation begin to be discharged and movable shale oil can be formed.

[0080] In the field of energy exploration and development, it can include the development of conventional oil and gas and the development of unconventional oil and gas, among which the development of unconventional oil and gas can include the development of continental shale oil. Continental shale oil resources have great potential, so the development of continental shale oil is becoming more and more significant. In the process of continental shale oil development, it is first necessary to determine the shale oil content grade, so as to determine the enrichment degree and distribution characteristics of oil and gas in the continental shale layer, and optimize resource allocation, providing scientific and reliable data support for the development of continental shale oil. Therefore, the determination of shale oil content grade is the basis for the development of continental shale oil.

[0081] In some embodiments, the shale sample can be excited by a laser light source, and based on the fluorescence characteristics of crude oil, multiple fluorescence signals can be received, and the multiple fluorescence signals can be separated and recombined for imaging, thereby determining the oil content of the shale sample, and then determining the shale oil content grade of the shale sample.

[0082] In the above embodiment, the oil content of the shale sample cannot be accurately determined only by measurement, and the shale oil content grade of the shale sample cannot be accurately determined.

[0083] In other embodiments, the shale sample can be analyzed and measured by pyrolysis and oil washing to obtain the oil-containing volume V0 in the effective pores of the shale sample and the effective pore volume V p . According to V0 and V p The oil saturation S0 is calculated, and the shale oil content grade of the shale sample is determined according to S0.

[0084] In the above embodiment, the oil-containing volume of the shale sample cannot be accurately determined when the shale sample is pyrolyzed and washed for oil, and thus the shale oil content grade of the shale sample cannot be accurately determined.

[0085] Therefore, in the above embodiments, the accuracy of determining the shale oil content grade of the shale sample is low.

[0086] The method for determining the shale oil content grade provided in the present application measures the free hydrocarbon content and the total organic carbon content of the shale samples in the target area, determines an outer envelope line according to the free hydrocarbon content and the total organic carbon content, determines multiple sub-areas in the area surrounded by the outer envelope line, determines which sub-area the shale sample falls into according to the measured free hydrocarbon content and the total organic carbon content of the shale sample, and determines that the shale oil content grade of the shale sample is the shale oil content grade corresponding to the sub-area. The accuracy of determining the shale oil content grade of the shale sample is improved.

[0087] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0088] Figure 1 Schematic diagram of the process of determining the shale oil content grade provided in this application Figure 1 ,like Figure 1 As shown, the method includes:

[0089] Step 101. Obtain a shale sample set in a target area; wherein the shale sample set includes a plurality of shale samples, and the shale samples have a free hydrocarbon content and a total organic carbon content.

[0090] As an example, the region where the shale oil content grade is to be determined is set as the target region, and multiple shale samples are obtained in the target region to form a shale sample set. Optionally, when multiple shale samples are obtained in the target region, shale samples can be obtained at different locations in the target region, and / or shale samples can be obtained at different depths in the target region. The shale samples are measured and analyzed to obtain the free hydrocarbon content S1 and the total organic carbon content TOC of each shale sample in the shale sample set.

[0091] The method of measuring and analyzing the shale sample to obtain the S1 and TOC of the shale sample is not specifically limited. In an optional embodiment, the shale sample can be measured and analyzed by a rock pyrolyzer to obtain the free hydrocarbon content of the shale sample; the shale sample can be measured and analyzed by a total organic carbon analyzer to obtain the total organic carbon content of the shale sample.

[0092] The rock pyrolyzer is an instrument used to measure and analyze the free hydrocarbon content in shale samples. When the shale sample is heated to nearly 300°C, the shale sample will volatilize hydrocarbons. The content of the volatilized hydrocarbons is measured by a hydrogen flame ionization detector (FID), thereby obtaining the S1 of the shale sample.

[0093] The total organic carbon analyzer is an instrument used to measure and analyze the total organic carbon content in shale samples. First, the shale sample can be treated with dilute hydrochloric acid to remove the inorganic carbon content in the shale sample; then the shale sample treated with dilute hydrochloric acid is burned, and the total organic carbon content of the shale sample is determined by detecting the concentration of carbon dioxide generated by combustion, thereby obtaining the TOC of the shale sample.

[0094] In the above example, the free hydrocarbon content and the total organic carbon content of the shale sample are determined by a rock pyrolyzer and a total organic carbon analyzer, which lays the foundation for the subsequent determination of the shale oil content grade of the shale sample based on the free hydrocarbon content and the total organic carbon content.

[0095] Step 102: Generate an outer envelope according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set; wherein the outer envelope surrounds the shale samples in the shale sample set.

[0096] The multiple shale samples in the shale sample set have corresponding S1 and corresponding TOC. It can be understood that each shale sample has a corresponding set of shale sample data, and the shale sample data includes S1 and TOC obtained by measuring and analyzing the shale sample.

[0097] As an example, a scatter plot can be formed based on a set of shale sample data corresponding to each shale sample. For example, the shale sample data is formed into a scatter plot in a coordinate system with the free hydrocarbon content S1 of the shale sample as the vertical axis and the total organic carbon content TOC as the horizontal axis. An outer envelope can be generated based on the scatter plot so that the outer envelope can surround the shale samples in the shale sample set. It can be understood that the outer envelope needs to surround the scattered points corresponding to the shale samples in the scatter plot.

[0098] Step 103: According to the outer envelope, the area surrounded by the outer envelope is determined as a plurality of sub-areas; wherein the sub-areas have corresponding shale oil content grades.

[0099] As an example, after obtaining the outer envelope in the coordinate system, the outer envelope and the coordinate axis of the coordinate system enclose an area, which can be divided into multiple sub-areas, and each sub-area has a corresponding shale oil content grade. The specific strategy for dividing multiple sub-areas is not limited in this embodiment.

[0100] Step 104: The shale oil content grade of the shale sample falling into the sub-region is the shale oil content grade corresponding to the sub-region.

[0101] As an example, in the coordinate system, according to the sub-region where the coordinate point falls, the shale oil content grade corresponding to the sub-region where the coordinate point falls is determined as the shale oil content grade of the shale sample corresponding to the coordinate point.

[0102] Exemplarily, the area enclosed by the outer envelope and the coordinate axis of the coordinate system is divided into three areas, which are respectively recorded as area A, area B and area C. The shale oil content level corresponding to area A is enriched resources, the shale oil content level corresponding to area B is inefficient resources, and the shale oil content level corresponding to area C is invalid resources. If the coordinate point corresponding to the shale sample falls into area A, the shale oil content level of the shale sample is determined to be enriched resources.

[0103] The method for determining the shale oil content grade provided in this embodiment collects shale samples in the target area to obtain a shale sample set consisting of multiple shale samples; the free hydrocarbon content and the total organic carbon content of the shale samples are determined by a rock pyrolyzer and a total organic carbon analyzer to obtain the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set, and the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set are obtained, and mapped on the coordinate system to obtain a scatter plot. An outer envelope is generated in the coordinate system, the outer envelope surrounds the coordinate points corresponding to the shale sample, and the area surrounded by the outer envelope is divided into multiple sub-areas, and according to which sub-area the shale sample falls into, the shale oil content grade of the shale sample is determined as the shale oil content grade corresponding to the sub-area. Determining the shale oil content grade of a shale sample according to the area where the coordinate point falls can improve the accuracy of determining the shale oil content grade.

[0104] Based on the above embodiments, this embodiment explains the strategy for determining the outer envelope. Figure 2 Schematic diagram of the process of determining the shale oil content grade provided in this application Figure 2 ,like Figure 2 As shown, the method includes:

[0105] Step 201. Establish a coordinate system with the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis.

[0106] Exemplarily, the coordinate system may be a plane rectangular coordinate system. Taking the plane rectangular coordinate system as an example, TOC is used as the horizontal axis of the coordinate system, and S1 is used as the vertical axis of the coordinate system. In the coordinate system, a set of shale sample data corresponding to each shale sample can determine a coordinate point in the coordinate system. It can be understood that multiple coordinate points can be obtained in the coordinate system, and each coordinate point corresponds to a shale sample. In the coordinate system, a scatter plot can be drawn according to the data of each shale sample in the shale sample set.

[0107] Step 202: Determine the shale sample to be processed whose free hydrocarbon content has the largest value when the total organic carbon content has the same value.

[0108] According to step 201, the coordinate system includes multiple coordinate points. Exemplarily, the multiple coordinate points are segmented according to TOC, the coordinate points corresponding to the maximum value of S1 are obtained in each segment, and the coordinate points corresponding to the maximum value of S1 are extracted.

[0109] For the case where the TOC values ​​appearing in each segment are the same, further, the coordinate point with the largest S1 value is selected from the multiple coordinate points with the same TOC values. The shale samples corresponding to the coordinate points with the largest S1 values ​​are determined as the shale samples to be processed. It can be understood that the shale samples to be processed are discrete.

[0110] Step 203: Obtain processed shale samples from discrete samples of the shale samples to be processed with the largest free hydrocarbon content.

[0111] According to step 202, the shale sample to be processed is the shale sample with the largest S1 value when the TOC values ​​are the same. The shale samples to be processed are screened to remove problematic samples from the shale samples to be processed.

[0112] Exemplarily, the horizontal axis can be divided into multiple sections, each section including multiple coordinate points. Taking the first section as an example, the median of the S1 values ​​of all coordinate points falling in the first section is calculated. If the difference between the S1 value of any coordinate point in the first section and the median exceeds a preset threshold, the coordinate point is determined as a problem point, and the shale sample corresponding to the problem point is determined as a problem sample. Repeat the above steps until the problem points in all sections are judged, and multiple problem samples in the discrete samples of the shale samples to be processed are obtained.

[0113] These problem samples are removed from the discrete samples in the shale samples to be processed to obtain each processed shale sample.

[0114] Step 204: Fit each processed shale sample to obtain an outer envelope.

[0115] Exemplarily, each processed shale sample corresponds to a plurality of coordinate points in the coordinate system, and the outer envelope can be fitted according to the positions of these coordinate points. Specifically, the fitting method is not limited in this embodiment, and for example, the fitting method includes but is not limited to: cubic spline interpolation, piecewise polynomial interpolation, and outer envelope fitting function.

[0116] As an example, Figure 3 is a schematic diagram of the outer envelope in an exemplary coordinate system. Figure 3As shown in the figure, when the TOC value is less than 0.3%, the oil generation potential is poor and the value of S1 at the coordinate point is low, because the water body where the shale sample is deposited is shallow, the debris input from the edge of the continental lake basin accounts for a large proportion, and the preservation condition of organic matter is poor. Therefore, when the TOC value is within the range of 0.3% to 0.8%, as the TOC value gradually increases, the water body where the shale sample is deposited becomes deeper, and the organic matter content in the shale sample increases. Therefore, when the TOC value is within the range of 0.3% to 0.8%, as the TOC value gradually increases, the water body where the shale sample is deposited becomes deeper, and the organic matter content in the shale sample increases. In the range of % to 0.8%, as the TOC value gradually increases, the oil generation potential gradually increases, and the value of S1 at the coordinate point gradually increases; when the TOC value is greater than 0.8, the water body where the shale sample is deposited further changes toward the deposition center, the deposited water body deepens, and the organic matter content remains at a high level. However, due to the deepening of the water body where the shale sample is deposited, the primary pores of the shale sample shrink, the storage capacity of the shale sample decreases, the oil generation potential gradually decreases, and the value of S1 at the coordinate point gradually decreases.

[0117] In an optional embodiment, the soluble organic matter content can be used as the vertical axis and TOC can be used as the horizontal axis to construct an outer envelope of the relationship between soluble organic matter and TOC. The outer envelope also has a trend of increasing first and then decreasing. The soluble organic matter content can be the content of chloroform asphalt.

[0118] Based on the above description, Figure 3 As shown, the obtained outer envelope has a trend of first increasing and then decreasing in the coordinate system, and the obtained outer envelope surrounds all coordinate points, that is, the obtained outer envelope surrounds the shale samples in the shale sample set.

[0119] The method for determining the oil content grade of shale provided in this embodiment is to establish a coordinate system by taking the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis, and obtain a scatter plot in the coordinate system according to the shale sample; and according to the shale sample set with the largest free hydrocarbon content when the total organic carbon content is the same; remove the problem sample according to the shale sample to be processed to obtain each processed shale sample; and fit the coordinate points corresponding to each processed shale sample to obtain the outer envelope. In the process of drawing the outer envelope, the change trend of the primary pores of the shale sample with the change of TOC value is taken into account, so that the drawn outer envelope is closer to the change trend of S1 of the actual shale sample with TOC, and the accuracy of determining the shale oil content grade of the shale sample is improved.

[0120] Based on the above embodiments, it can be known that the shale oil content grade of the shale sample is determined by which sub-region the shale sample falls into in the coordinate system. Therefore, based on any of the above embodiments, this embodiment explains the process of determining the region surrounded by the outer envelope as multiple sub-regions.

[0121] Figure 4 Schematic diagram of the process of determining the shale oil content grade provided in this application Figure 3 , Figure 5 is a schematic diagram of the division of exemplary sub-areas. Figure 4 As shown, the method includes:

[0122] Step 401: Generate a preset straight line.

[0123] The slope value of the preset straight line is a preset value, the preset straight line has the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis; the preset straight line passes through the origin of the coordinate system where the outer envelope line is located.

[0124] As an example, a preset straight line is generated in the coordinate system where the outer envelope line is located. The preset straight line is a straight line passing through the origin of the coordinate system. It can be understood that the preset straight line and the outer envelope line are in the same coordinate system. Therefore, the preset straight line also uses TOC as the horizontal axis and S1 as the vertical axis. According to the definition of the slope of a straight line in a coordinate system, the slope of the preset straight line can be obtained by dividing S1 by TOC. The slope value of the generated preset straight line can be set to a preset value. The specific value of the preset value is not limited. The larger the preset value, the steeper the preset straight line appears in the coordinate system; the smaller the preset value, the gentler the preset straight line appears in the coordinate system.

[0125] Furthermore, since the coordinate system uses TOC as the horizontal axis and S1 as the vertical axis, it can be understood that the slope of the preset straight line is the ratio of S1 to TOC. According to the definition of the oil saturation index OSI, the slope of the preset straight line multiplied by 100 can be obtained to obtain OSI.

[0126] When the OSI value is greater than 100 mg / g, it is considered that the hydrocarbons generated in the shale formation begin to be discharged and mobile shale oil can be formed. Optionally, the OSI threshold can be set to 100 mg / g; accordingly, Figure 5 As shown, the slope of the preset straight line can be set to 1, and the preset straight line is generated through the origin of the coordinate system.

[0127] Step 402: According to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas.

[0128] The preset straight line can first divide the area surrounded by the outer envelope into two sub-areas. For example, the area surrounded by the outer envelope can be further divided into multiple sub-areas by the following steps:

[0129] Step 4021. Determine the intersection point between the preset straight line and the outer envelope line as the first intersection point.

[0130] like Figure 5As shown, the preset straight line and the outer envelope intersect at point A, and point A can be recorded as the first intersection point. Further, the coordinates of point A can be obtained by combining the expression of the preset straight line and the expression of the outer envelope. The coordinates of point A can be recorded as A(TOC", S1').

[0131] Step 4022. Draw a perpendicular line from the first intersection point to the horizontal axis of the coordinate system to obtain a first perpendicular line, and draw a perpendicular line from the first intersection point to the vertical axis of the coordinate system to obtain a second perpendicular line.

[0132] like Figure 5 As shown, a perpendicular line is drawn through point A to the horizontal axis of the coordinate system to obtain a first perpendicular line; and a perpendicular line is drawn through point A to the vertical axis of the coordinate system to obtain a second perpendicular line.

[0133] Step 4023. Determine the intersection point between the second perpendicular line and the outer envelope line as the second intersection point; and draw a perpendicular line from the second intersection point to the horizontal axis of the coordinate system to obtain the third perpendicular line.

[0134] like Figure 5 As shown, the second vertical line intersects the outer envelope line at point B, and point B can be recorded as the second intersection point. According to step 4022, point A and point B are both on the second vertical line. Therefore, the ordinate values ​​of point A and point B are the same, both S1'. Further, the abscissa of point B can be obtained based on the expression of the outer envelope line. The coordinates of point B can be recorded as B(TOC', S1').

[0135] Step 4024. Determine multiple sub-areas based on the outer envelope, the first vertical line, the second vertical line and the third vertical line.

[0136] like Figure 5 As shown, the outer envelope, the first vertical line, the second vertical line and the third vertical line can divide the area surrounded by the outer envelope into multiple sub-areas. Exemplarily, the definition of each sub-area can be performed by the following steps:

[0137] Step 403: Determine the area enclosed by the outer envelope and the second vertical line as the first sub-area among the multiple sub-areas.

[0138] The area enclosed by the outer envelope and the second vertical line is determined as the first sub-area, that is, Figure 5 The area marked with “①” in the figure, and the corresponding shale oil content grade in this area is rich resources.

[0139] The shale samples in the first sub-area have a TOC value between TOC' and TOC", and an S1 value above S1'. These shale samples have a high degree of shale oil enrichment, which is conducive to exploitation. Therefore, the shale oil content of the shale samples falling into the first sub-area can be determined as enriched resources.

[0140] Step 404: Determine the area enclosed by the second vertical line, the preset straight line and the third vertical line as the second sub-area among the multiple sub-areas.

[0141] The area enclosed by the second vertical line, the preset straight line and the third vertical line is determined as the second sub-area, that is, Figure 5 The area marked with “②” in the figure has a shale oil content grade of medium-rich resources.

[0142] The shale samples in the second sub-area have TOC values ​​between TOC' and TOC", S1 values ​​below S1', and OSI values ​​greater than 100 mg / g. The S1 values ​​of these shale samples are lower than those of the shale samples with rich resources, indicating that the total amount of hydrocarbon substances in the shale samples is relatively small, but because the OSI value is greater than 100 mg / g, the shale oil still has a certain mobility. Therefore, the shale oil content grade of the shale samples falling into the second sub-area can be determined as medium-rich resources.

[0143] Step 405: Determine that the area enclosed by the first vertical line, the preset straight line and the third vertical line is the third sub-area among the multiple sub-areas.

[0144] The area enclosed by the first vertical line, the preset straight line and the third vertical line is determined as the third sub-area, that is, Figure 5 The area marked “③” in the figure, and the corresponding shale oil content grade in this area is low-efficiency resource.

[0145] The shale samples in the third sub-area have TOC values ​​between TOC' and TOC", S1 values ​​below S1', and OSI values ​​less than 100 mg / g. The S1 values ​​of these shale samples are lower than those of the shale samples with rich resources, indicating that the total amount of hydrocarbon substances in the shale samples is relatively small, and because the OSI value is less than 100 mg / g, the mobility of shale oil is also poor. Therefore, the shale oil content grade of the shale samples falling into the third sub-area can be determined as low-efficiency resources.

[0146] Step 406: Determine that the area surrounded by the outer envelope, excluding the first sub-area, the second sub-area, and the third sub-area, is the fourth sub-area among the multiple sub-areas.

[0147] After the first sub-region, the second sub-region and the third sub-region are determined, Figure 5 As shown, the remaining part of the area surrounded by the outer envelope is determined as the fourth sub-area, that is, Figure 5 The area marked “④” in the figure has an invalid shale oil content grade.

[0148] The TOC value of the shale samples in the fourth sub-area is less than TOC' or greater than TOC". When the TOC value of the shale sample is less than TOC', the total organic carbon content in the shale sample is low and the oil generation capacity is poor; when the TOC value of the shale sample is greater than TOC", although the total organic carbon content in the shale sample is high, the storage capacity of shale oil is poor due to the reduction of the primary pore control in the shale sample. Therefore, the shale oil content grade of the shale samples falling into the fourth sub-area can be determined as invalid resources.

[0149] It should be noted that the above steps 403 to 405 can be executed simultaneously or sequentially, and the order of execution is not limited.

[0150] It should also be noted that Figure 5 This is only used as an example to illustrate the strategy of sub-region division. In actual applications, the coordinate system should also include coordinate points corresponding to multiple shale samples. Figure 6 Schematic diagram of shale oil content grades for exemplary shale samples.

[0151] like Figure 6 As shown, the four sub-regions are Figure 5 The serial number corresponds to Figure 6 The legend in the figure shows the range of each sub-region. Figure 6 It includes multiple coordinate points, and each coordinate point corresponds to the S1 value and TOC value of a shale sample. The shale oil content grade of the shale sample corresponding to the coordinate point is determined according to the area where the coordinate point falls. In this example, the TOC" value determined according to the preset straight line and the outer envelope line is 2.2%, and the S1' value is 2.2 mg / g. The TOC' value determined according to the second vertical line and the outer envelope line is 0.4%. The above-mentioned TOC" value, TOC' value and S1' value are all determined by the data of the shale sample in this example, and this example does not specifically limit the above-mentioned TOC" value, TOC' value and S1' value.

[0152] It should be noted that most of the coordinate points corresponding to the shale samples in the coordinate system will fall in the sub-area. For a small number of coordinate points falling on the above-mentioned dividing line, it is necessary to separately determine the shale oil content grade of the shale samples corresponding to the coordinate points falling on the above-mentioned dividing line.

[0153] For example, if a coordinate point falls on the outer envelope line, the coordinate point falling on the outer envelope line can be identified as being within the area surrounded by the outer envelope line, and it can be further determined in which sub-area the coordinate point falling on the outer envelope line is; if a coordinate point falls on the first vertical line, since the right side of the first vertical line is the sub-area of ​​invalid resources, the coordinate point falling on the first vertical line can be judged to be within the fourth sub-area, that is, the shale oil content grade of the shale sample corresponding to the coordinate point is invalid resources; if a coordinate point falls on the second vertical line, since the upper side of the second vertical line is the sub-area of ​​enriched resources, the coordinate point falling on the second vertical line can be judged to be within the fourth sub-area. In the first sub-area, the shale oil content grade of the shale sample corresponding to the coordinate point is enriched resource; if a coordinate point falls on the preset straight line, since the upper side of the preset straight line is the sub-area of ​​medium-enriched resources, the coordinate point falling on the preset straight line can be judged as falling in the second sub-area, that is, the shale oil content grade of the shale sample corresponding to the coordinate point is medium-enriched resource; if a coordinate point falls on the third vertical line, since the left side of the third vertical line is the sub-area of ​​invalid resources, the coordinate point falling on the third vertical line can be judged as falling in the fourth sub-area, that is, the shale oil content grade of the shale sample corresponding to the coordinate point is invalid resource.

[0154] The method for determining the shale oil content grade provided in this embodiment generates a preset straight line in a coordinate system, and determines a first intersection point according to the preset straight line and the outer envelope line, and draws a first perpendicular line to the horizontal axis of the coordinate system and a second perpendicular line to the vertical axis of the coordinate system from the first intersection point; determines a second intersection point according to the second perpendicular line and the outer envelope line, and draws a third perpendicular line from the second intersection point to the horizontal axis of the coordinate axis. Multiple sub-areas are divided by the outer envelope line, the first perpendicular line, the second perpendicular line, and the third perpendicular line, and the shale oil content grade of the shale sample is determined as the shale oil content grade corresponding to the sub-area according to which sub-area the coordinate point of the shale sample falls. When dividing the sub-areas, the different structural parts of the shale sample and the factors of the primary pores in the shale sample are taken into consideration, and the sub-areas are divided according to the outer envelope line and the preset straight line, and different shale oil content grades are assigned to the sub-areas, thereby improving the efficiency of determining the shale oil content grade of the shale sample, and further improving the accuracy of determining the shale oil content grade of the shale sample.

[0155] Based on the method for determining the shale oil content grade provided in any of the aforementioned embodiments, this embodiment determines the shale oil content grade of shale samples at different depths of a target single well in a target area.

[0156] At different depths of the target single well in the target area, shale samples are obtained, and the S1 and TOC of the shale samples at different depths are measured and analyzed, and the outer envelope is drawn according to the method of the above embodiment to divide the sub-areas. The shale oil content grade of the shale samples at different depths of the target single well is evaluated. Figure 7 The following is the evaluation result of shale oil content grade at different depths of the target single well. Figure 7 As shown in the figure, the first column of data is the section of the formation, the second column of data is the depth information of the target single well, the third column of data is the core lithology; the fourth column of data includes spontaneous potential (SP), wellbore characteristics (CALI), and natural gamma ray intensity (GR); the fifth column of data includes flushing resistivity (R XO ), original resistivity (R T ), medium induction resistivity (R I ); the sixth column of data includes permeability and porosity; the seventh column of data is total organic carbon content (TOC); the eighth column of data is free hydrocarbon content (S1); the ninth column of data is oil saturation index (OSI); the tenth column of data is soluble organic matter content; the eleventh to thirteenth columns are the results of judging the shale oil content grade of shale samples by the three-point method, the four-point method and the method provided in this application; the fourteenth column is the cumulative oil field output during trial production.

[0157] Combination Figure 7 Analysis shows that at the first analysis point, the method provided in this application determines that the shale sample corresponding to the first analysis point is a medium-enriched resource. On the one hand, the actual corresponding trial production cumulative oil field output is also relatively high; on the other hand, the three-part method and the four-part method determine that the shale sample corresponding to the first analysis point is an invalid resource, and the three-part method and the four-part method determine that the actual corresponding trial production cumulative oil field output is relatively high. This shows that the method for determining the shale oil content grade provided in this application can accurately determine the shale oil content grade of the shale sample.

[0158] Furthermore, combined with Figure 7 Analysis shows that at the second analysis point, the solution provided by this application determines that the shale sample corresponding to the second analysis point is an inefficient resource. On the one hand, the actual corresponding trial production cumulative oil field output is indeed low; on the other hand, the three-part method determines that the shale sample corresponding to the second analysis point is an enriched resource, and the four-part method determines that the shale sample corresponding to the second analysis point is a medium-enriched resource, which is inconsistent with the actual corresponding trial production cumulative oil field output. This further reflects the accuracy of the shale oil content grade determination method provided by this application in determining the shale oil content grade of shale samples.

[0159] In the above embodiment, shale samples at different depths are selected in a target single well in a target area, and the shale oil content grade of the shale samples is determined according to the method for determining the shale oil content grade provided in the present application, which proves the superiority of the accuracy of the method for determining the shale oil content grade provided in the present application.

[0160] Figure 8The schematic diagram of the structure of the device for determining the oil content grade of shale provided in this application is as follows: Figure 8 As shown, the shale oil content grade determination device 80 provided in this embodiment includes:

[0161] The acquisition module 801 is used to acquire a shale sample set in a target area; wherein the shale sample set includes a plurality of shale samples, and the shale samples have a free hydrocarbon content and a total organic carbon content;

[0162] The processing module 802 is used to generate an outer envelope according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set; wherein the outer envelope surrounds the shale samples in the shale sample set;

[0163] The processing module 802 is further used to determine the area surrounded by the outer envelope line into multiple sub-areas according to the outer envelope line; wherein the sub-areas have corresponding shale oil content grades;

[0164] The processing module 802 is further configured to determine the shale oil content level of the shale sample falling into the sub-region as the shale oil content level corresponding to the sub-region.

[0165] In a possible implementation, an outer envelope is generated according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set, and the processing module 802 is used to:

[0166] A coordinate system is established with the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis;

[0167] Determine the shale sample to be processed that has the largest free hydrocarbon content when the total organic carbon content has the same value;

[0168] Obtaining each processed shale sample from discrete samples of the shale samples to be processed with the largest value of each free hydrocarbon content;

[0169] The outer envelope was obtained by fitting the shale samples after each treatment.

[0170] In a possible implementation, according to the outer envelope, the area surrounded by the outer envelope is determined as a plurality of sub-areas, and the processing module 802 is used to:

[0171] Generate a preset straight line; wherein the slope value of the preset straight line is a preset value, the preset straight line takes the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis; the preset straight line passes through the origin of the coordinate system where the outer envelope line is located;

[0172] According to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas.

[0173] In a possible implementation, according to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas, and the processing module 802 is used to:

[0174] Determine the intersection point between the preset straight line and the outer envelope line as the first intersection point;

[0175] A first perpendicular line is obtained by drawing a perpendicular line from the first intersection point to the horizontal axis of the coordinate system, and a second perpendicular line is obtained by drawing a perpendicular line from the first intersection point to the vertical axis of the coordinate system;

[0176] Determine the intersection point between the second perpendicular line and the outer envelope line as the second intersection point; and draw a perpendicular line from the second intersection point to the horizontal axis of the coordinate system to obtain a third perpendicular line;

[0177] A plurality of sub-areas are determined according to the outer envelope, the first vertical line, the second vertical line, and the third vertical line.

[0178] In a possible implementation, a plurality of sub-areas are determined according to the outer envelope, the first vertical line, the second vertical line, and the third vertical line, and the processing module 802 is used to:

[0179] Determine an area enclosed by the outer envelope and the second perpendicular line as a first sub-area among the sub-areas;

[0180] Determine an area enclosed by the second vertical line, the preset straight line, and the third vertical line as a second sub-area in the multiple sub-areas;

[0181] Determine an area enclosed by the first vertical line, the preset straight line, and the third vertical line as a third sub-area among the multiple sub-areas;

[0182] It is determined that the area surrounded by the outer envelope, excluding the first sub-area, the second sub-area, and the third sub-area, is the fourth sub-area among the plurality of sub-areas.

[0183] In a possible implementation, a shale sample set in a target area is obtained, and the obtaining module 801 is used to:

[0184] The shale samples are measured and analyzed by a rock pyrolysis instrument to obtain the free hydrocarbon content of the shale samples;

[0185] The shale samples are measured and analyzed by a total organic carbon analyzer to obtain the total organic carbon content of the shale samples.

[0186] The device for determining the oil content grade of shale provided in this embodiment can execute the method provided in the above method embodiment, and its implementation principle and technical effect are similar, so this embodiment will not be described in detail here.

[0187] Fig. 9 This is a schematic diagram of the structure of the electronic device provided in this application. Fig. 9As shown, the electronic device 90 provided in this embodiment includes: at least one processor 901 and a memory 902. Optionally, the device 90 further includes a communication component 903. The processor 901, the memory 902 and the communication component 903 are connected via a bus 904.

[0188] In a specific implementation process, at least one processor 901 executes the computer execution instructions stored in the memory 902, so that at least one processor 901 executes the above method.

[0189] The specific implementation process of the processor 901 can be found in the above method embodiment, and its implementation principle and technical effect are similar, so this embodiment will not be repeated here.

[0190] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the application may be directly implemented as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0191] The memory may include a high-speed memory (Random Access Memory, RAM), and may also include a non-volatile memory (Non-volatile Memory, NVM), such as at least one disk memory.

[0192] The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus in the drawings of the present application is not limited to only one bus or one type of bus.

[0193] The present application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0194] The present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the above method is implemented.

[0195] The above-mentioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The readable storage medium can be any available medium that can be accessed by a general or special-purpose computer.

[0196] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (Application Specific Integrated Circuits, referred to as: ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0197] The division of modules is only a logical function division. There may be other divisions in actual implementation, such as multiple modules can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, which can be electrical, mechanical or other forms.

[0198] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0199] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0200] If the function is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, and other media that can store program codes.

[0201] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk and other media that can store program codes.

[0202] Finally, it should be noted that those skilled in the art will readily conceive of other embodiments of the present application after considering the specification and practicing the application disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary technical means in the art that are not disclosed in the present application, are not limited to the precise structures described above and shown in the drawings, and may be modified and changed in various ways without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for determining the oil content grade of shale, characterized in that: include: Acquire a shale sample set in a target area; wherein the shale sample set includes a plurality of shale samples, and the shale samples have a free hydrocarbon content and a total organic carbon content; Generate an outer envelope according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set; wherein the outer envelope surrounds the shale samples in the shale sample set; According to the outer envelope, the area surrounded by the outer envelope is determined as a plurality of sub-areas; wherein the sub-areas have corresponding shale oil content grades; The shale oil content grade of the shale samples falling into the sub-region is the shale oil content grade corresponding to the sub-region.

2. The method according to claim 1, characterized in that An outer envelope is generated according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set, including: A coordinate system is established with the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis; Determine the shale sample to be processed that has the largest free hydrocarbon content when the total organic carbon content has the same value; Obtaining each processed shale sample from discrete samples of the shale samples to be processed having the largest free hydrocarbon content; The outer envelope is obtained by fitting each processed shale sample.

3. The method according to claim 1, characterized in that According to the outer envelope, the area surrounded by the outer envelope is determined as a plurality of sub-areas, including: Generate a preset straight line; wherein the slope value of the preset straight line is a preset value, the preset straight line takes the total organic carbon content as the horizontal axis and the free hydrocarbon content as the vertical axis; the preset straight line passes through the origin of the coordinate system where the outer envelope line is located; According to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas.

4. The method according to claim 3, characterized in that According to the outer envelope and the preset straight line, the area surrounded by the outer envelope is determined as a plurality of sub-areas, including: Determine an intersection point between the preset straight line and the outer envelope line as a first intersection point; A first perpendicular line is obtained by drawing a perpendicular line from the first intersection point to the horizontal axis of the coordinate system, and a second perpendicular line is obtained by drawing a perpendicular line from the first intersection point to the vertical axis of the coordinate system; Determine the intersection point between the second perpendicular line and the outer envelope line as the second intersection point; and draw a perpendicular line from the second intersection point to the horizontal axis of the coordinate system to obtain a third perpendicular line; The plurality of sub-areas are determined according to the outer envelope, the first vertical line, the second vertical line, and the third vertical line.

5. The method according to claim 4, characterized in that Determining the plurality of sub-areas according to the outer envelope, the first perpendicular line, the second perpendicular line, and the third perpendicular line comprises: Determine an area enclosed by the outer envelope and the second vertical line as a first sub-area among the multiple sub-areas; Determine an area enclosed by the second vertical line, the preset straight line, and the third vertical line as a second sub-area among the multiple sub-areas; Determine an area enclosed by the first vertical line, the preset straight line, and the third vertical line as a third sub-area among the multiple sub-areas; It is determined that a region within the region surrounded by the outer envelope excluding the first sub-region, the second sub-region, and the third sub-region is a fourth sub-region among the plurality of sub-regions.

6. The method according to any one of claims 1 to 5, characterized in that Obtain a collection of shale samples in the target area, including: Measuring and analyzing the shale sample by a rock pyrolysis instrument to obtain the free hydrocarbon content of the shale sample; The shale sample is measured and analyzed by a total organic carbon analyzer to obtain the total organic carbon content of the shale sample.

7. A device for determining the oil content grade of shale, characterized in that: include: An acquisition module, used to acquire a shale sample set in a target area; wherein the shale sample set includes a plurality of shale samples, and the shale samples have a free hydrocarbon content and a total organic carbon content; A processing module, configured to generate an outer envelope according to the free hydrocarbon content and the total organic carbon content of the shale samples in the shale sample set; wherein the outer envelope surrounds the shale samples in the shale sample set; The processing module is further used to determine the area surrounded by the outer envelope line into a plurality of sub-areas according to the outer envelope line; wherein the sub-areas have corresponding shale oil content grades; The processing module is also used to determine the shale oil content grade of the shale samples falling into the sub-region as the shale oil content grade corresponding to the sub-region.

8. An electronic device, characterized in that: include: Memory, processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the processor performs the method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 6 when executed by a processor.

10. A computer program product, characterized in that The invention comprises a computer program, which implements the method according to any one of claims 1 to 6 when being executed by a processor.

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