Method and device for distinguishing types of shale oil reservoirs

Abstract

The invention provides a shale oil reservoir type discrimination method and device, and relates to the technical field of geological exploration and development, and the method comprises the steps: carrying out the pyrolysis and total organic carbon content analysis of a shale oil reservoir pressure-maintaining sealed core in a research area, and determining a crude oil accumulation cause type corresponding to a shale oil reservoir based on a hydrocarbon generation potential discrimination method; a crude oil storage space corresponding to the shale oil reservoir is determined through microscopic analysis based on a laser confocal method; geological data and crude oil storage space corresponding to the shale oil reservoir of the research area are obtained, and the reservoir type corresponding to the shale oil reservoir is determined according to the geological data; and determining the shale oil reservoir type based on the reservoir type corresponding to the shale oil reservoir and the crude oil aggregation cause type. According to the method, the shale oil reservoir type is judged by taking the shale oil cause difference as the main basis, the shale oil reservoir characteristics can be reliably revealed, a reliable evaluation basis is provided for subsequent oil reservoir resource analysis, and the effectiveness of subsequent oil reservoir exploration deployment and development scheme selection is improved.

Description

Technical Field

[0001] The present application relates to the technical field of geological exploration and development, and in particular to a method and device for distinguishing the type of shale oil reservoir. Background Art

[0002] Shale oil is an unconventional oil and gas resource. Its reservoir characteristics are significantly different from those of conventional trapped accumulation reservoirs. It does not have typical trapped characteristics and lacks a unified oil-water interface. It is generally accumulated within the source or near the source, and the reservoirs are characterized by large-scale continuous enrichment. Therefore, due to the differences in reservoir characteristics and genesis, the reservoir type classification method for shale oil cannot be copied from conventional reservoirs.

[0003] At present, there is no scientific and reliable method for the classification of shale oil reservoir types. In the process of exploration practice, shale oil is generally divided into pure shale type, mixed type and interlayer type according to the type of shale oil reservoir. This classification method is mainly based on the reservoir characteristics of shale oil. It is a qualitative description method and is easily affected by human subjective factors, resulting in inaccurate reservoir type classification. Moreover, this method does not truly classify shale oil reservoirs based on their causes, and cannot provide strong support for the subsequent use of reservoir types for reservoir resource analysis and exploration and development deployment. Summary of the invention

[0004] In view of this, the purpose of the present application is to at least provide a method and device for distinguishing the type of shale oil reservoirs. By distinguishing the type of shale oil reservoirs based mainly on the differences in the genesis of shale oil, the characteristics of shale oil reservoirs can be reliably revealed, providing a reliable evaluation basis for subsequent reservoir resource analysis, and improving the effectiveness of subsequent reservoir exploration deployment and development plan selection.

[0005] This application mainly includes the following aspects: In the first aspect, an embodiment of the present application provides a method for identifying the type of shale oil reservoir, the method comprising: performing pyrolysis and total organic carbon content analysis on pressure-maintained sealed cores of shale oil reservoirs in a study area, and determining the crude oil accumulation genesis type corresponding to the shale oil reservoir based on a hydrocarbon generation potential identification method; determining the crude oil storage space corresponding to the shale oil reservoir through microscopic analysis based on a laser confocal method; obtaining geological data and crude oil storage space corresponding to the shale oil reservoir in the study area, and determining the reservoir type corresponding to the shale oil reservoir based on the geological data; and determining the shale oil reservoir type based on the reservoir type and crude oil accumulation genesis type corresponding to the shale oil reservoir.

[0006] In one possible implementation, the crude oil accumulation genesis type corresponding to the shale oil reservoir is determined in the following manner: pyrolysis and total organic carbon content analysis are performed on the pressure-maintained sealed cores corresponding to the shale oil reservoirs in the study area to determine the pyrolysis and total organic carbon parameters corresponding to the shale oil reservoirs; based on the pyrolysis and total organic carbon parameters, the current hydrocarbon generation potential index and the original hydrocarbon generation potential index corresponding to the shale oil reservoir are determined; based on the current hydrocarbon generation potential index and the original hydrocarbon generation potential index, the crude oil accumulation genesis type corresponding to the shale oil reservoir is determined.

[0007] In one possible embodiment, the pyrolysis and total organic carbon parameters include the amount of pyrolysis free hydrocarbons, the amount of thermal cracking hydrocarbons and the total organic carbon content corresponding to the shale oil reservoir, wherein the current hydrocarbon generation potential index corresponding to the shale oil reservoir is determined by: calculating the first sum between the amount of pyrolysis free hydrocarbons and the amount of thermal cracking hydrocarbons; and determining the ratio between the first sum and the total organic carbon content as the current hydrocarbon generation potential index corresponding to the shale oil reservoir.

[0008] In a possible embodiment, the pyrolysis and total organic carbon parameters also include a maximum pyrolysis peak temperature, wherein the original hydrocarbon generation potential corresponding to the shale oil reservoir is determined in the following manner: based on the ratio between the pyrolysis hydrocarbon content and the total organic carbon content, the organic matter type parameter corresponding to the shale oil reservoir is determined, and the organic matter type parameter indicates the kerogen type corresponding to the shale oil reservoir; based on the organic matter type parameter, the maximum pyrolysis peak temperature and a preset kerogen hydrocarbon generation conversion rate map, the corresponding target hydrocarbon generation conversion rate in the shale oil reservoir is determined, and the preset kerogen hydrocarbon generation conversion rate map describes the mapping relationship between the maximum pyrolysis peak temperature and the hydrocarbon generation conversion rate corresponding to different kerogen types; based on the pyrolysis and total organic carbon parameters and the target hydrocarbon generation conversion rate, the original hydrocarbon generation potential index corresponding to the shale oil reservoir is calculated.

[0009] In one possible embodiment, the pyrolysis and total organic carbon parameters include the amount of thermal cracking hydrocarbons and the total organic carbon content, wherein the original hydrocarbon generation potential index corresponding to the shale oil reservoir is calculated in the following manner: calculating a first ratio between the amount of thermal cracking hydrocarbons and the total organic carbon content; calculating the difference between 1 and the target hydrocarbon generation conversion rate; and determining a second ratio between the first ratio and the difference as the original hydrocarbon generation potential index corresponding to the shale oil reservoir.

[0010] In one possible embodiment, the crude oil accumulation genesis type includes retention type, intra-source migration type and micro-migration type, wherein the crude oil accumulation genesis type corresponding to the shale oil reservoir is determined by the following method: calculating the second difference between the current hydrocarbon generation potential index and the original hydrocarbon generation potential index; if it is determined that the second difference is greater than zero, then the crude oil accumulation genesis type corresponding to the shale oil reservoir is determined to be the intra-source migration type; if it is determined that the second difference is less than zero, shale samples in the shale oil reservoir are selected for fluorescence thin section and laser confocal analysis, and the crude oil storage space and organic matter enrichment position in the shale oil reservoir are determined according to the analysis results; according to the crude oil storage space and organic matter enrichment position in the shale oil reservoir, it is determined that the crude oil accumulation genesis type corresponding to the shale oil reservoir is the retention type or the micro-migration type.

[0011] In a possible embodiment, the step of determining whether the crude oil accumulation type corresponding to the shale oil reservoir is a retention type or a micro-migration type based on the crude oil storage space and the organic matter enrichment position in the shale oil reservoir includes: determining the vertical microscopic migration distance of hydrocarbon molecules based on the crude oil storage space and the organic matter enrichment position in the shale oil reservoir; if the vertical microscopic migration distance of hydrocarbon molecules is in a first distance interval, determining that the crude oil accumulation type corresponding to the shale oil reservoir is a retention type; if it is determined that the vertical microscopic migration distance of hydrocarbon molecules is in a second distance interval, determining that the crude oil accumulation type corresponding to the shale oil reservoir is a micro-migration type.

[0012] In a possible implementation, the geological data at least includes reservoir lithology, mineral components and sedimentary structures, and the reservoir types include matrix type, foliation type, lamination type and interlayer type, wherein the reservoir type corresponding to the shale oil reservoir is determined in the following manner: if the reservoir lithology is massive mudstone, the mineral components are clay minerals, quartz, feldspar and carbonate minerals, and the clay mineral content is higher than the preset clay mineral content upper limit, the sedimentary structure is massive, and the main enrichment area corresponding to the crude oil is the mudstone matrix pore, then the shale oil reservoir is determined to be a matrix reservoir; If the reservoir lithology is shale, the mineral components are clay minerals, quartz and feldspar, and the clay mineral content is higher than the preset upper limit of clay mineral content, the main crude oil enrichment area is foliation fractures, and the sedimentary structure is developed in book-shaped foliation, then the shale oil reservoir is determined to be a foliated reservoir; if the reservoir lithology is laminated shale, the types of mineral components exceed the preset number, the clay mineral content is lower than the preset lower limit of clay mineral content, the carbonate rock mineral content exceeds the preset carbonate rock mineral content threshold, the main crude oil enrichment area is the pores of coarse clastic laminae, and the sedimentary structure indicates that clay laminae and feldspar laminae or carbonate laminae are interlayered and superimposed, then the shale oil reservoir is determined to be a laminated reservoir; if the reservoir lithology is a thin layer of sandstone or carbonate rock within the shale oil reservoir system, and the main crude oil enrichment area is the pores of sandstone or carbonate interlayers, then the shale oil reservoir is determined to be an interlayer reservoir.

[0013] In a possible embodiment, based on the reservoir type corresponding to the shale oil reservoir and the crude oil accumulation genesis type, the step of determining the shale oil reservoir type includes: if the reservoir type corresponding to the shale oil reservoir is a matrix reservoir or a laminated reservoir, and the crude oil accumulation genesis type is a retention type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be an in-situ retention type shale oil reservoir; if the reservoir type corresponding to the shale oil reservoir is a laminar reservoir, and the crude oil accumulation genesis type is a micro-migration type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be a micro-migration laminar-enriched shale oil reservoir; if the reservoir type corresponding to the shale oil reservoir is an interlayer reservoir, and the crude oil accumulation genesis type is an intra-source migration type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be an intra-source migration interlayer-enriched shale oil reservoir.

[0014] In a second aspect, an embodiment of the present application also provides a device for distinguishing the type of shale oil reservoir, the device comprising: a first analysis module, used to perform pyrolysis and total organic carbon content analysis on the pressure-maintained sealed core of the shale oil reservoir in the study area, and determine the crude oil accumulation genesis type corresponding to the shale oil reservoir based on the hydrocarbon generation potential distinction method; a second analysis module, used to determine the crude oil storage space corresponding to the shale oil reservoir through microscopic analysis based on the laser confocal method; a reservoir type determination module, which obtains the geological data and crude oil storage space corresponding to the shale oil reservoir in the study area, and determines the reservoir type corresponding to the shale oil reservoir based on the geological data; and a reservoir type determination module, which is used to determine the shale oil reservoir type based on the reservoir type and crude oil accumulation genesis type corresponding to the shale oil reservoir.

[0015] The embodiment of the present application provides a method and device for distinguishing the type of shale oil reservoir, the method comprising: pyrolysis and total organic carbon content analysis of the pressure-maintained sealed core of the shale oil reservoir in the study area, and determining the crude oil accumulation genesis type corresponding to the shale oil reservoir based on the hydrocarbon generation potential distinction method; microscopic analysis based on the laser confocal method determines the crude oil storage space corresponding to the shale oil reservoir; obtains the geological data and crude oil storage space corresponding to the shale oil reservoir in the study area, and determines the reservoir type corresponding to the shale oil reservoir based on the geological data; determines the shale oil reservoir type based on the reservoir type corresponding to the shale oil reservoir and the crude oil accumulation genesis type. The present application distinguishes the shale oil reservoir type based on the differences in shale oil genesis as the main basis, and can reliably reveal the characteristics of the shale oil reservoir, provide reliable data support for subsequent reservoir resource analysis, and improve the accuracy of subsequent reservoir analysis.

[0016] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A flow chart showing a method for distinguishing shale reservoir types provided in an embodiment of the present application is shown; Figure 2 The charts of hydrocarbon generation conversion rates of different types of kerogens provided in the examples of the present application are shown; Figure 3 A shale reservoir type identification chart provided in an embodiment of the present application is shown; Figure 4 A functional module diagram of a shale reservoir type identification device provided in an embodiment of the present application is shown; Figure 5 A schematic structural diagram of an electronic device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0019] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0020] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0021] There is no scientific and reliable method for the classification of shale oil reservoir types. In the process of exploration practice, shale oil is generally divided into pure shale type, mixed type and interlayer type according to the type of shale oil reservoir. This classification method is mainly based on the reservoir characteristics of shale oil. It is a qualitative description method and is easily affected by human subjective factors, resulting in inaccurate reservoir type classification. Moreover, this method does not truly classify shale oil reservoirs based on their causes, and cannot provide strong data support for the subsequent use of reservoir types for reservoir resource analysis.

[0022] Based on this, the embodiment of the present application provides a method and device for distinguishing the type of shale oil reservoir. By distinguishing the type of shale oil reservoir based on the differences in the genesis of shale oil as the main basis, the characteristics of shale oil reservoirs can be reliably revealed, a reliable evaluation basis can be provided for subsequent reservoir resource analysis, and the effectiveness of subsequent reservoir exploration deployment and development plan selection can be improved. The details are as follows: See also Figure 1 , Figure 1 A flow chart of a method for distinguishing shale reservoir types provided in an embodiment of the present application is shown. Figure 1 As shown, the method provided in the embodiment of the present application comprises the following steps: S100. Pyrolysis and total organic carbon content analysis were performed on the pressure-sealed cores of the shale oil reservoirs in the study area, and the crude oil accumulation genesis type corresponding to the shale oil reservoirs was determined based on the hydrocarbon generation potential discrimination method.

[0023] S200. Determine the crude oil storage space corresponding to the shale oil reservoir through microscopic analysis based on the laser confocal method.

[0024] S300, obtaining geological data and crude oil storage space corresponding to the shale oil reservoir in the study area, and determining the reservoir type corresponding to the shale oil reservoir based on the geological data.

[0025] S400: Determine the shale oil reservoir type based on the reservoir type corresponding to the shale oil reservoir and the crude oil accumulation genesis type.

[0026] In a specific implementation, step S100 includes: Pyrolysis and total organic carbon content analysis were carried out on the pressure-maintained sealed cores corresponding to the shale oil reservoirs in the study area to determine the pyrolysis and total organic carbon parameters corresponding to the shale oil reservoirs. Based on the pyrolysis and total organic carbon parameters, the current hydrocarbon generation potential index and the original hydrocarbon generation potential index corresponding to the shale oil reservoirs were determined. According to the current hydrocarbon generation potential index and the original hydrocarbon generation potential index, the crude oil accumulation genesis type corresponding to the shale oil reservoir was determined.

[0027] Specifically, the pressure-maintained sealed cores corresponding to the shale oil reservoirs in the study area are obtained, and the total organic carbon and pyrolysis analysis tests are performed on the pressure-maintained sealed cores under low-temperature nitrogen protection conditions to obtain the pyrolysis and total organic carbon parameters corresponding to the shale oil reservoirs. The pyrolysis and total organic carbon parameters include but are not limited to at least one of the following items: total organic carbon content TOC, pyrolysis free hydrocarbon amount S1, thermal cracking hydrocarbon amount S2, and maximum pyrolysis peak temperature Tmax. Based on the pyrolysis and total organic carbon parameters, the current hydrocarbon generation potential index and the original hydrocarbon generation potential index of the shale oil reservoir can be further calculated.

[0028] In a preferred embodiment, the current hydrocarbon generation potential index corresponding to the shale oil reservoir is determined by: The first sum of the amount of pyrolysis free hydrocarbons and the amount of pyrolysis hydrocarbons is calculated, and the ratio of the first sum to the total organic carbon content is determined as the current hydrocarbon generation potential index corresponding to the shale oil reservoir.

[0029] In a specific embodiment, the current hydrocarbon generation potential index corresponding to the shale oil reservoir is determined by the following formula: :

[0030] In a preferred embodiment, the original hydrocarbon generation potential corresponding to the shale oil reservoir is determined by: According to the thermal cracking hydrocarbon amount S2 and total organic carbon content The ratio between the maximum pyrolysis peak temperature Tmax and the maximum pyrolysis peak temperature Tmax is used to determine the organic matter type parameter corresponding to the shale oil reservoir. The organic matter type parameter indicates the kerogen type corresponding to the shale oil reservoir. According to the organic matter type parameter, the maximum pyrolysis peak temperature Tmax and the preset kerogen hydrocarbon generation conversion rate chart, the corresponding target hydrocarbon generation conversion rate in the shale oil reservoir is determined. The preset kerogen hydrocarbon generation conversion rate chart describes the mapping relationship between the maximum pyrolysis peak temperature Tmax and the hydrocarbon generation conversion rate corresponding to different kerogen types. According to the pyrolysis and total organic carbon parameters and the target hydrocarbon generation conversion rate, the original hydrocarbon generation potential index corresponding to the shale oil reservoir is calculated.

[0031] In a specific embodiment, the classification of kerogen types is usually carried out based on the ratio between the amount of pyrolysis hydrocarbons S2 and the total organic carbon content TOC, see Figure 2 , Figure 2 The following diagram shows the hydrocarbon conversion rate of different types of kerogen provided in the examples of this application. Figure 2 As shown, kerogen types include type I kerogen, Type kerogen, Type kerogen and Type III kerogen. The horizontal axis in the figure represents the maximum pyrolysis peak temperature Tmax in degrees Celsius, and the vertical axis represents the hydrocarbon conversion rate. Each curve in the figure describes the maximum pyrolysis peak temperature Tmax and hydrocarbon conversion rate of the corresponding type. The mapping relationship between Figure 2 After determining the kerogen type corresponding to the shale oil reservoir according to the ratio between the amount of pyrolysis hydrocarbon S2 and the total organic carbon content TOC, the application searches for Figure 2 The corresponding curve shown in the figure, combined with the maximum pyrolysis peak temperature Tmax, can determine the target hydrocarbon conversion rate corresponding to the shale oil reservoir , further, combined with the target hydrocarbon conversion rate , the original hydrocarbon generation potential index corresponding to the shale oil reservoir can be determined.

[0032] In a specific embodiment, the original hydrocarbon generation potential index corresponding to the shale oil reservoir is calculated in the following manner: A first ratio between the amount of thermal cracking hydrocarbons and the total organic carbon content is calculated, the difference between 1 and the target hydrocarbon generation conversion rate is calculated, and a second ratio between the first ratio and the difference is determined as the original hydrocarbon generation potential index corresponding to the shale oil reservoir.

[0033] In one example, the original hydrocarbon generation potential index corresponding to the shale oil reservoir is determined by the following formula: .

[0034]

[0035] Preferably, the crude oil accumulation genesis types include retention type, intra-source migration type and micro-migration type.

[0036] In a preferred embodiment, the crude oil accumulation type corresponding to the shale oil reservoir is determined by the following formula: The second difference between the current hydrocarbon generation potential index and the original hydrocarbon generation potential index is calculated. If it is determined that the second difference is greater than zero, the crude oil accumulation genesis type corresponding to the shale oil reservoir is determined to be the intra-source migration type. If it is determined that the second difference is less than zero, shale samples in the shale oil reservoir are selected for fluorescence thin section and laser confocal analysis. The crude oil storage space and organic matter enrichment position in the shale oil reservoir are determined according to the analysis results. According to the crude oil storage space and organic matter enrichment position in the shale oil reservoir, the crude oil accumulation genesis type corresponding to the shale oil reservoir is determined to be the retention type or the micro-migration type.

[0037] In a specific embodiment, the second difference between the current hydrocarbon generation potential index corresponding to the shale oil reservoir and the original hydrocarbon generation potential index is calculated. ,according to Determine whether there is macroscopic migration in the shale oil reservoir corresponding to the shale oil reservoir. >0, it is determined that there is macroscopic migration in the shale oil reservoir, and the crude oil accumulation type corresponding to the shale oil reservoir is determined to be intra-source migration type. <0, judge There is basically no macroscopic migration, and the crude oil accumulation type corresponding to the shale oil reservoir is determined to be in-situ retention or micro-migration accumulation.

[0038] If it is determined that there is no macroscopic migration in the shale oil reservoir, shale samples are selected for fluorescence thin section and laser confocal analysis to determine the crude oil storage space and organic matter enrichment position in the shale oil reservoir. Based on the crude oil storage space and organic matter enrichment position, the vertical microscopic migration distance of hydrocarbon molecules is determined. Combined with the distance interval of the vertical microscopic migration distance of hydrocarbon molecules, it is further determined whether the crude oil accumulation genesis type corresponding to the shale oil reservoir is retention type or micromigration type.

[0039] In a specific embodiment, the organic matter enrichment position in the shale oil reservoir is determined based on fluorescent thin sections and laser confocal analysis, and then the vertical distance of the organic matter enrichment position relative to the crude oil storage space is further calculated, and the vertical distance is determined as the vertical microscopic migration distance of hydrocarbon molecules.

[0040] In a preferred embodiment, the crude oil accumulation genesis type corresponding to the shale oil reservoir is also determined by: If the vertical microscopic migration distance of hydrocarbon molecules is in the first distance interval, the crude oil accumulation type corresponding to the shale oil reservoir is determined to be a retention type; if the vertical microscopic migration distance of hydrocarbon molecules is in the second distance interval, the crude oil accumulation type corresponding to the shale oil reservoir is determined to be a micromigration type.

[0041] Specifically, the vertical microscopic migration distance of hydrocarbon molecules transitions from the nanometer level to the meter level, and the upper limit value corresponding to the first distance interval is smaller than the lower limit value of the second distance interval.

[0042] In step S200, the laser confocal microscopic analysis performed in step S100 can be combined to obtain the crude oil storage space corresponding to the shale oil reservoir.

[0043] In step S300, the geological data at least includes reservoir lithology, mineral composition elements and sedimentary structure, and the reservoir types include matrix type, foliation type, lamination type and interlayer type.

[0044] In a preferred embodiment, step S300 includes: If the reservoir lithology is massive mudstone, the mineral components are clay minerals, quartz, feldspar and carbonate minerals, and the clay mineral content is higher than the preset upper limit of clay mineral content, the sedimentary structure is massive, and the main enrichment area corresponding to crude oil is the mudstone matrix pores, then the shale oil reservoir is determined to be a matrix reservoir.

[0045] If the reservoir lithology is shale, the mineral components are clay minerals, quartz and feldspar, and the clay mineral content is higher than the preset upper limit of clay mineral content, the main crude oil enrichment area is foliation gaps, and the sedimentary structure is developed in book-like foliation, then the shale oil reservoir is determined to be a foliated reservoir.

[0046] If the reservoir lithology is laminated shale, the types of mineral components exceed the preset number, the clay mineral content is lower than the preset clay mineral content lower limit, the carbonate mineral content exceeds the preset carbonate mineral content threshold, the main crude oil enrichment area is the pores of coarse clastic laminae, and the sedimentary structure indicates that clay laminae and feldspar laminae or carbonate laminae are interlayered and superimposed, then the shale oil reservoir is determined to be a laminated reservoir.

[0047] If the reservoir lithology is a thin layer of sandstone or carbonate rock within the shale oil reservoir system, and the main crude oil enrichment area is the pores of the sandstone or carbonate interlayer, then the shale oil reservoir is determined to be an interlayer reservoir.

[0048] In the present application, the preset upper limit of clay mineral content may be 40%.

[0049] In a preferred embodiment, step S400 includes: If the reservoir type corresponding to the shale oil reservoir is a matrix reservoir or a foliation reservoir, and the crude oil accumulation genesis type is a retention type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be an in-situ retention shale oil reservoir.

[0050] If the reservoir type corresponding to the shale oil reservoir is a laminar reservoir and the crude oil accumulation genesis type is a micro-migration type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be a micro-migration laminar-enriched shale oil reservoir.

[0051] If the reservoir type corresponding to the shale oil reservoir is an interlayer reservoir and the crude oil accumulation genesis type is an intra-source migration type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be an intra-source migration interlayer enriched shale oil reservoir.

[0052] See also Figure 3 , Figure 3 A shale reservoir type identification chart provided in the embodiment of the present application is shown. Figure 3In the shale reservoir type identification chart shown, the horizontal axis represents the vertical microscopic migration distance of hydrocarbon molecules. Different vertical microscopic migration distance intervals of hydrocarbon molecules correspond to different crude oil accumulation genesis types. The first distance interval corresponds to the retention type, the second distance interval corresponds to the micromigration type, and the third distance interval corresponds to the intra-source migration type. The vertical axis represents the sedimentary structure thickness corresponding to the shale oil reservoir. Different sedimentary structure thickness intervals correspond to different reservoir types. The sedimentary structure thickness interval corresponding to the matrix reservoir and the lamellar reservoir is 0~1mm (millimeter), the sedimentary structure thickness interval corresponding to the laminar reservoir is 1mm ~1dm (decimeter), and the sedimentary structure thickness interval corresponding to the interlayer reservoir is 1dm ~5m (meter). In this application, the above method of this application is combined with Figure 3 The shale reservoir type identification chart shown can further determine the shale reservoir type.

[0053] The present application provides a shale reservoir type identification method that integrates macro-micro multi-scales and is based mainly on differences in shale oil genesis. The method can reliably reveal shale reservoir characteristics and improve the accuracy of shale reservoir type identification. At the same time, it can provide scientific guidance for subsequent resource / reserve calculations, exploration deployment, and development plans based on shale reservoir types, thereby improving the accuracy of subsequent analysis.

[0054] Based on the same application concept, the embodiments of the present application also provide a shale reservoir type identification device corresponding to the shale reservoir type identification method provided in the above embodiments. Since the principle of solving the problem by the device in the embodiments of the present application is similar to the shale reservoir type identification method in the above embodiments of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0055] See also Figure 4 , Figure 4 The functional module diagram of a shale reservoir type identification device provided in an embodiment of the present application is shown. Figure 4 As shown, the device comprises: The first analysis module 500 is used to perform pyrolysis and total organic carbon content analysis on the pressure-maintained sealed core of the shale oil reservoir in the study area, and determine the crude oil accumulation genesis type corresponding to the shale oil reservoir based on the hydrocarbon generation potential discrimination method; The second analysis module 510 is used to determine the crude oil storage space corresponding to the shale oil reservoir based on the laser confocal microscopic analysis method; The reservoir type determination module 520 obtains geological data and crude oil storage space corresponding to the shale oil reservoir in the study area, and determines the reservoir type corresponding to the shale oil reservoir according to the geological data; The oil reservoir type determination module 530 is used to determine the shale oil reservoir type based on the reservoir type corresponding to the shale oil reservoir and the crude oil accumulation genesis type.

[0056] Based on the same application idea, please refer to Figure 5 , Figure 5 FIG. 1 is a schematic diagram showing the structure of an electronic device provided by an embodiment of the present application. Figure 5 As shown, the electronic device 600 includes: a processor 610, a memory 620 and a bus 630. The memory 620 stores machine-readable instructions executable by the processor 610. When the electronic device 600 is running, the processor 610 and the memory 620 communicate through the bus 630. The machine-readable instructions are executed by the processor 610 when it is running, such as the steps of the method for distinguishing the shale reservoir type provided in any of the above embodiments.

[0057] Based on the same application concept, an embodiment of the present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the shale reservoir type identification method provided in the above embodiment are executed.

[0058] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. In the several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components 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 communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0059] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0060] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0061] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile computer-readable storage medium that is executable by a processor. 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. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0062] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for distinguishing shale reservoir types, characterized in that: The method comprises: The shale oil reservoir pressure-sealed cores in the study area were subjected to pyrolysis and total organic carbon content analysis, and the crude oil accumulation genesis type corresponding to the shale oil reservoir was determined based on the hydrocarbon generation potential discrimination method; Determine the crude oil storage space corresponding to the shale oil reservoir by microscopic analysis based on the laser confocal method; Obtaining geological data corresponding to the shale oil reservoir in the study area and the crude oil storage space, and determining the reservoir type corresponding to the shale oil reservoir according to the geological data; The shale oil reservoir type is determined based on the reservoir type corresponding to the shale oil reservoir and the crude oil accumulation genesis type.

2. The method according to claim 1, characterized in that: The crude oil accumulation genesis type corresponding to the shale oil reservoir is determined by: The pyrolysis and total organic carbon content analysis of the pressure-retaining sealed cores corresponding to the shale oil reservoirs in the study area were carried out to determine the pyrolysis and total organic carbon parameters corresponding to the shale oil reservoirs; Based on the pyrolysis and total organic carbon parameters, determining a current hydrocarbon generation potential index and an original hydrocarbon generation potential index corresponding to the shale oil reservoir; The crude oil accumulation genesis type corresponding to the shale oil reservoir is determined according to the current hydrocarbon generation potential index and the original hydrocarbon generation potential index.

3. The method according to claim 2, characterized in that The pyrolysis and total organic carbon parameters include the amount of pyrolysis free hydrocarbons, the amount of pyrolysis hydrocarbons and the total organic carbon content corresponding to the shale oil reservoir. The current hydrocarbon generation potential index corresponding to the shale oil reservoir is determined by: calculating a first sum value between the amount of pyrolysis free hydrocarbons and the amount of pyrolysis cracked hydrocarbons; The ratio between the first sum value and the total organic carbon content is determined as the current hydrocarbon generation potential index corresponding to the shale oil reservoir.

4. The method according to claim 3, characterized in that The pyrolysis and total organic carbon parameters also include the maximum pyrolysis peak temperature, Among them, the original hydrocarbon generation potential corresponding to the shale oil reservoir is determined by the following methods: Determining an organic matter type parameter corresponding to the shale oil reservoir according to the ratio between the amount of pyrolysis hydrocarbons and the total organic carbon content and the maximum pyrolysis peak temperature, wherein the organic matter type parameter indicates the kerogen type corresponding to the shale oil reservoir; Determine the corresponding target hydrocarbon generation conversion rate in the shale oil reservoir according to the organic matter type parameter, the maximum pyrolysis peak temperature and the preset kerogen hydrocarbon generation conversion rate chart, wherein the preset kerogen hydrocarbon generation conversion rate chart describes the mapping relationship between the maximum pyrolysis peak temperature and the hydrocarbon generation conversion rate corresponding to different kerogen types; The original hydrocarbon generation potential index corresponding to the shale oil reservoir is calculated according to the pyrolysis and total organic carbon parameters and the target hydrocarbon generation conversion rate.

5. The method according to claim 4, characterized in that The pyrolysis and total organic carbon parameters include the amount of pyrolysis hydrocarbons and the total organic carbon content. Among them, the original hydrocarbon generation potential index corresponding to the shale oil reservoir is calculated by the following method: calculating a first ratio between the amount of pyrolysis hydrocarbons and the total organic carbon content; Calculate the difference between 1 and the target hydrocarbon generation conversion rate; A second ratio between the first ratio and the difference is determined as the original hydrocarbon generation potential index corresponding to the shale oil reservoir.

6. The method according to claim 2, characterized in that The types of crude oil accumulation in the shale oil reservoir include retention type, intra-source migration type and micro-migration type. The crude oil accumulation genesis type corresponding to the shale oil reservoir is determined by: Calculating a second difference between the current hydrocarbon generation potential index and the original hydrocarbon generation potential index; If it is determined that the second difference is greater than zero, it is determined that the crude oil accumulation type corresponding to the shale oil reservoir is an intra-source migration type; If it is determined that the second difference is less than zero, selecting a shale sample in the shale oil reservoir for fluorescence thin section and laser confocal analysis, and determining the crude oil storage space and organic matter enrichment position in the shale oil reservoir according to the analysis results; According to the crude oil storage space and the organic matter enrichment position in the shale oil reservoir, it is determined that the crude oil accumulation genesis type corresponding to the shale oil reservoir is a retention type or a micro-migration type.

7. The method according to claim 6, characterized in that According to the crude oil storage space and the organic matter enrichment position in the shale oil reservoir, the step of determining whether the crude oil accumulation genesis type corresponding to the shale oil reservoir is a retention type or a micro-migration type comprises: Determining the vertical microscopic migration distance of hydrocarbon molecules according to the crude oil storage space and organic matter enrichment position in the shale oil reservoir; If the vertical microscopic migration distance of hydrocarbon molecules is in the first distance interval, it is determined that the crude oil accumulation type corresponding to the shale oil reservoir is the retention type; If it is determined that the vertical microscopic migration distance of hydrocarbon molecules is in the second distance interval, then the crude oil accumulation genesis type corresponding to the shale oil reservoir is determined to be micro-migration type.

8. The method according to claim 1, characterized in that The geological data at least include reservoir lithology, mineral composition elements and sedimentary structure, and the reservoir types include matrix type, foliation type, lamination type and interlayer type. The reservoir type corresponding to the shale oil reservoir is determined by: If the reservoir lithology is massive mudstone, the mineral components are clay minerals, quartz, feldspar and carbonate minerals, and the clay mineral content is higher than the preset clay mineral content upper limit, the sedimentary structure is massive, and the main enrichment area corresponding to the crude oil is the mudstone matrix pores, then the shale oil reservoir is determined to be a matrix reservoir; If the reservoir lithology is shale, the mineral components are clay minerals, quartz and feldspar, and the clay mineral content is higher than the preset clay mineral content upper limit, the main crude oil enrichment area is foliation gaps, and the sedimentary structure is book-shaped foliation development, then the shale oil reservoir is determined to be a foliated reservoir; If the reservoir lithology is laminated shale, the types of mineral components exceed the preset number, the clay mineral content is lower than the preset clay mineral content lower limit, the carbonate rock mineral content exceeds the preset carbonate rock mineral content threshold, the main crude oil enrichment area is the pores of the coarse clastic laminae, and the sedimentary structure indicates that clay laminae and feldspar laminae or carbonate laminae are interlayered and superimposed, then the shale oil reservoir is determined to be a laminated reservoir; If the reservoir lithology is a thin layer of sandstone or carbonate rock in a shale oil reservoir system, and the main crude oil enrichment area is the pores of the sandstone or carbonate interlayer, then the shale oil reservoir is determined to be an interlayer reservoir.

9. The method according to claim 1, characterized in that: Based on the reservoir type and crude oil accumulation genesis type corresponding to the shale oil reservoir, the steps to determine the shale oil reservoir type include: If the reservoir type corresponding to the shale oil reservoir is a matrix reservoir or a foliation reservoir, and the crude oil accumulation genesis type is a retention type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be an in-situ retention shale oil reservoir; If the reservoir type corresponding to the shale oil reservoir is a laminar reservoir and the crude oil accumulation genesis type is a micro-migration type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be a micro-migration laminar-enriched shale oil reservoir; If the reservoir type corresponding to the shale oil reservoir is an interlayer reservoir and the crude oil accumulation genesis type is an intra-source migration type, then the shale oil reservoir type corresponding to the shale oil reservoir is determined to be an intra-source migration interlayer enriched shale oil reservoir.

10. A device for distinguishing shale oil reservoir types, characterized in that: The device comprises: The first analysis module is used to perform pyrolysis and total organic carbon content analysis on the pressure-maintained sealed core of the shale oil reservoir in the study area to determine the crude oil accumulation genesis type corresponding to the shale oil reservoir; A second analysis module is used to determine the crude oil storage space corresponding to the shale oil reservoir based on a laser confocal microscopic analysis method; A reservoir type determination module, which obtains geological data corresponding to the shale oil reservoir in the study area and the crude oil storage space, and determines the reservoir type corresponding to the shale oil reservoir according to the geological data; The oil reservoir type determination module is used to determine the shale oil reservoir type based on the reservoir type corresponding to the shale oil reservoir and the crude oil accumulation genesis type.

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