A method and device for discriminating shale reservoir types

Abstract

The present application provides a method and device for discriminating shale reservoir types, relating to the technical field of geological exploration and development, including: performing pyrolysis and total organic carbon content analysis on pressure-maintained sealed cores of shale oil reservoirs in the study area, and determining the genetic type of crude oil accumulation corresponding to the shale oil reservoir based on the hydrocarbon generation potential discrimination method; microscopically analyzing and determining the crude oil storage space corresponding to the shale oil reservoir based on the laser confocal method; obtaining the 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 according to the geological data; and determining the shale reservoir type based on the reservoir type and crude oil accumulation genetic type corresponding to the shale oil reservoir. By discriminating shale reservoir types mainly based on the differences in shale oil genesis, the present application can reliably reveal the characteristics of shale reservoirs, provide a reliable evaluation basis for subsequent reservoir resource analysis, and improve the effectiveness of subsequent reservoir exploration deployment and development plan selection.

Description

Technical Field

[0001] This application relates to the technical field of geological exploration and development, and particularly relates to a method and device for discriminating shale reservoir types. Background Art

[0002] Shale oil is an unconventional oil and gas resource. Its reservoir characteristics are significantly different from those of conventional trap-accumulated oil reservoirs. It does not have typical trap characteristics and lacks a unified oil-water interface. Generally, it accumulates within the source rock or near the source rock, and the reservoir shows the characteristics of large-area continuous enrichment. Therefore, due to the differences in reservoir characteristics and formation mechanisms, the method for classifying shale reservoir types cannot be directly applied from conventional oil reservoirs.

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

[0004] In view of this, the purpose of this application is to provide at least a method and device for discriminating shale reservoir types. By using the differences in shale oil formation mechanisms as the main basis for discriminating shale reservoir types, it can reliably reveal the characteristics of shale reservoirs, provide a reliable evaluation basis for subsequent reservoir resource analysis, and improve the effectiveness of subsequent reservoir exploration deployment and development plan selection.

[0005] This application mainly includes the following aspects:

[0006] In the first aspect, an embodiment of this application provides a method for discriminating shale reservoir types. The method includes: performing pyrolysis and total organic carbon content analysis on the pressure-maintained sealed cores of shale oil reservoirs in the study area, and determining the crude oil accumulation origin type corresponding to the shale oil reservoir based on the hydrocarbon generation potential discrimination method; microscopically analyzing and determining the crude oil storage space corresponding to the shale oil reservoir based on the laser confocal method; obtaining the 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 according to the geological data; and determining the shale reservoir type based on the reservoir type and crude oil accumulation origin type corresponding to the shale oil reservoir.

[0007] 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.

[0008] 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.

[0009] 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.

[0010] 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.

[0011] In a possible implementation manner, the genetic types of crude oil accumulation include the retention type, the in-source migration type, and the micro-migration type. Among them, the genetic type of crude oil accumulation corresponding to the shale oil reservoir is determined by the following method: 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, determining that the genetic type of crude oil accumulation corresponding to the shale oil reservoir is the in-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 the 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, determining that the genetic type of crude oil accumulation corresponding to the shale oil reservoir is the retention type or the micro-migration type.

[0012] In a possible implementation manner, the steps of determining that the genetic type of crude oil accumulation corresponding to the shale oil reservoir is the retention type or the micro-migration type according to the crude oil storage space and the organic matter enrichment position in the shale oil reservoir include: measuring the vertical microscopic migration distance of hydrocarbon molecules according to 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 the first distance interval, determining that the genetic type of crude oil accumulation 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, determining that the genetic type of crude oil accumulation corresponding to the shale oil reservoir is the micro-migration type.

[0013] In a possible implementation manner, the geological data at least includes reservoir lithology, mineral composition elements, and sedimentary structures. The reservoir types include the matrix type, the bedding type, the laminar type, and the interlayer type. Among them, the reservoir type corresponding to the shale oil reservoir is determined by the following method: if the reservoir lithology is massive mudstone, the mineral composition elements are clay minerals, quartz, feldspar, and carbonate rock minerals, and the clay mineral content is higher than the upper limit of the preset clay mineral content, the sedimentary structure is massive, and the main enrichment area corresponding to the crude oil is the pores in the mudstone matrix, determining that the shale oil reservoir is a matrix type reservoir; if the reservoir lithology is shale, the mineral composition elements are clay minerals, quartz, and feldspar, and the clay mineral content is higher than the upper limit of the preset clay mineral content, the main enrichment area of the crude oil is the bedding fissures, and the sedimentary structure shows the development of book-shaped bedding, determining that the shale oil reservoir is a bedding type reservoir; if the reservoir lithology is laminated shale, the types of mineral composition elements exceed the preset number, the clay mineral content is lower than the lower limit of the preset clay mineral content, the carbonate rock mineral content exceeds the preset carbonate rock mineral content threshold, the main enrichment area of the crude oil is the pores in the coarse clastic laminae, and the sedimentary structure indicates the interbedded development of clayey laminae and quartzofeldspathic laminae or carbonate rock laminae, determining that the shale oil reservoir is a laminar type reservoir; if the reservoir lithology is a sandstone or carbonate rock thin layer in the shale oil reservoir series, and the main enrichment area of the crude oil is the pores in the sandstone or carbonate rock interlayer, determining that the shale oil reservoir is an interlayer type reservoir.

[0014] In a possible implementation manner, based on the reservoir type corresponding to the shale oil reservoir and the type of crude oil accumulation origin, the steps of determining the shale oil reservoir type include: if the reservoir type corresponding to the shale oil reservoir is a matrix-type reservoir or a bedding-type reservoir, and the type of crude oil accumulation origin is a retention type, then it is determined that the shale oil reservoir type corresponding to the shale oil reservoir is an in-situ retention type shale oil reservoir; if the reservoir type corresponding to the shale oil reservoir is a laminar-type reservoir, and the type of crude oil accumulation origin is a micro-migration type, then it is determined that the shale oil reservoir type corresponding to the shale oil reservoir is a micro-migration laminar enrichment type shale oil reservoir; if the reservoir type corresponding to the shale oil reservoir is an interlayer-type reservoir, and the type of crude oil accumulation origin is an in-source migration type, then it is determined that the shale oil reservoir type corresponding to the shale oil reservoir is an in-source migration interlayer enrichment type shale oil reservoir.

[0015] In a second aspect, an apparatus for discriminating shale oil reservoir types provided by an embodiment of the present application includes: a first analysis module, configured to perform pyrolysis and total organic carbon content analysis on a pressure-maintained sealed core of a shale oil reservoir in a study area, and determine the type of crude oil accumulation origin corresponding to the shale oil reservoir based on a hydrocarbon generation potential discrimination method; a second analysis module, configured to microscopically analyze and determine the crude oil storage space corresponding to the shale oil reservoir based on a laser confocal method; a reservoir type determination module, configured to obtain geological data and the crude oil storage space corresponding to the shale oil reservoir in the study area, and determine the reservoir type corresponding to the shale oil reservoir according to the geological data; an oil reservoir type determination module, configured to determine the shale oil reservoir type based on the reservoir type and the type of crude oil accumulation origin corresponding to the shale oil reservoir.

[0016] A method and apparatus for discriminating shale oil reservoir types provided by an embodiment of the present application, the method includes: performing pyrolysis and total organic carbon content analysis on a pressure-maintained sealed core of a shale oil reservoir in a study area, and determining the type of crude oil accumulation origin corresponding to the shale oil reservoir based on a hydrocarbon generation potential discrimination method; microscopically analyzing and determining the crude oil storage space corresponding to the shale oil reservoir based on a laser confocal method; obtaining geological data and the 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 according to the geological data; determining the shale oil reservoir type based on the reservoir type and the type of crude oil accumulation origin corresponding to the shale oil reservoir. By discriminating shale oil reservoir types mainly based on the differences in shale oil genesis, the present application can reliably reveal the characteristics of shale oil reservoirs, provide reliable data support for subsequent oil reservoir resource analysis, and improve the accuracy of subsequent oil reservoir analysis.

[0017] To make the above objects, features, and advantages of the present application more obvious and understandable, the following specifically enumerates preferred embodiments and, in conjunction with the accompanying drawings, makes a detailed description as follows. Description of the Drawings

[0018] To more clearly illustrate the technical solutions of the embodiments of the present application, the accompanying drawings required for the embodiments will be briefly introduced below. It should be understood that the following accompanying drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related accompanying drawings can be obtained based on these drawings.

[0019] Figure 1 The flowchart of a method for discriminating shale reservoir types provided by the embodiments of the present application is shown;

[0020] Figure 2 The hydrocarbon generation conversion rate charts of different types of kerogens provided by the embodiments of the present application are shown;

[0021] Figure 3 A shale reservoir type discrimination chart provided by the embodiments of the present application is shown;

[0022] Figure 4 The functional module diagram of a device for discriminating shale reservoir types provided by the embodiments of the present application is shown;

[0023] Figure 5 The structural schematic diagram of an electronic device provided by the embodiments of the present application is shown. Specific embodiments

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. It should be understood that the accompanying drawings in the present application only serve for illustration and description purposes and are not used to limit the protection scope of the present application. Additionally, it should be understood that the schematic accompanying drawings are not drawn to scale. The flowcharts used in the present application show the operations implemented according to some embodiments of the present application. It should be understood that the operations in the flowchart may not be implemented in sequence, and steps without logical context relationships may be reversed or implemented simultaneously. Moreover, those skilled in the art can add one or more other operations to the flowchart or remove one or more operations from the flowchart under the guidance of the content of the present application.

[0025] In addition, the described embodiments are only some embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application claimed, but only 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 creative efforts fall within the protection scope of the present application.

[0026] There is no scientific and reliable method for classifying shale reservoir types. In the process of exploration practice, shale oil is generally classified into pure shale type, mixed sedimentary type, and interlayer type according to the type of shale oil reservoir. This classification method is mainly based on the characteristics of the reservoir body of shale oil and is a qualitative description method, which is easily affected by human subjective factors, resulting in inaccurate classification of reservoir types. Moreover, this method does not truly classify the types based on the origin of shale reservoirs and cannot provide strong data support for subsequent reservoir resource analysis using reservoir types.

[0027] Based on this, the embodiments of the present application provide a method and device for discriminating shale reservoir types. By mainly relying on the differences in the origin of shale oil to discriminate shale reservoir types, it can reliably reveal the characteristics of shale reservoirs, provide a reliable evaluation basis for subsequent reservoir resource analysis, and improve the effectiveness of subsequent reservoir exploration deployment and development plan selection, as follows:

[0028] Please refer to Figure 1 , Figure 1 which shows the flow chart of a method for discriminating shale reservoir types provided by the embodiments of the present application. As Figure 1 shown, the method provided by the embodiments of the present application includes the following steps:

[0029] S100. Perform pyrolysis and total organic carbon content analysis on the pressure-maintained sealed cores of shale oil reservoirs in the study area, and determine the crude oil accumulation origin type corresponding to the shale oil reservoir based on the hydrocarbon generation potential discrimination method.

[0030] S200. Microscopically analyze and determine the crude oil storage space corresponding to the shale oil reservoir based on the laser confocal method.

[0031] S300. Obtain the geological data and crude oil storage space corresponding to the shale oil reservoir in the study area, and determine the reservoir type corresponding to the shale oil reservoir according to the geological data.

[0032] S400. Determine the shale reservoir type based on the reservoir type and crude oil accumulation origin type corresponding to the shale oil reservoir.

[0033] In specific implementation, step S100 includes:

[0034] Perform pyrolysis and total organic carbon content analysis on the pressure-maintained sealed cores corresponding to the shale oil reservoirs in the study area, determine the pyrolysis and total organic carbon parameters corresponding to the shale oil reservoirs, based on the pyrolysis and total organic carbon parameters, determine the current hydrocarbon generation potential index and the original hydrocarbon generation potential index corresponding to the shale oil reservoirs, and determine the crude oil accumulation origin type corresponding to the shale oil reservoirs according to the current hydrocarbon generation potential index and the original hydrocarbon generation potential index.

[0035] Specifically, obtain the pressure-maintained sealed core corresponding to the shale oil reservoir in the study area, conduct total organic carbon and pyrolysis analysis tests on the pressure-maintained sealed core under the condition of low-temperature nitrogen protection, and obtain the pyrolysis and total organic carbon parameters corresponding to the shale oil reservoir. The pyrolysis and total organic carbon parameters include at least one of the following items: total organic carbon content TOC, pyrolysis free hydrocarbon amount S1, pyrolytic 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.

[0036] In a preferred embodiment, the current hydrocarbon generation potential index corresponding to the shale oil reservoir is determined by the following method:

[0037] Calculate the first sum value between the pyrolysis free hydrocarbon amount and the pyrolytic cracking hydrocarbon amount, and determine the ratio between the first sum value and the total organic carbon content as the current hydrocarbon generation potential index corresponding to the shale oil reservoir.

[0038] In a specific embodiment, the current hydrocarbon generation potential index corresponding to the shale oil reservoir is determined by the following formula :

[0039]

[0040] In a preferred embodiment, the original hydrocarbon generation potential corresponding to the shale oil reservoir is determined by the following method:

[0041] According to the ratio between the pyrolytic cracking hydrocarbon amount S2 and the total organic carbon content and the maximum pyrolysis peak temperature Tmax, 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, determine the target hydrocarbon generation conversion rate corresponding to the shale oil reservoir. The preset kerogen hydrocarbon generation conversion rate chart describes the mapping relationship between the maximum pyrolysis peak temperature Tmax corresponding to different kerogen types and the hydrocarbon generation conversion rate. According to the pyrolysis and total organic carbon parameters and the target hydrocarbon generation conversion rate, calculate the original hydrocarbon generation potential index corresponding to the shale oil reservoir.

[0042] In a specific embodiment, the classification of kerogen types is usually carried out according to the ratio between the pyrolytic cracking hydrocarbon amount S2 and the total organic carbon content TOC. Please refer to Figure 2 , Figure 2 shows the hydrocarbon generation conversion rate charts of different types of kerogens provided in the embodiments of the present application. As Figure 2 shown, the kerogen types include type I kerogen, type kerogen, type kerogen, and type III kerogen. In the chart, the abscissa represents the maximum pyrolysis peak temperature Tmax, with the unit of degree Celsius (°C), and the ordinate represents the hydrocarbon generation conversion rate , each curve in the plate depicts the mapping relationship between the maximum pyrolysis peak temperature Tmax of the corresponding type and the hydrocarbon generation conversion rate between, based on Figure 2 , after determining the kerogen type corresponding to the shale oil reservoir according to the ratio between the pyrolysis hydrocarbon amount S2 and the total organic carbon content TOC in this application, by looking up Figure 2 the corresponding curve shown in the plate and combining the maximum pyrolysis peak temperature Tmax, the target hydrocarbon generation conversion rate corresponding to the shale oil reservoir can be determined . Further, by combining the target hydrocarbon generation conversion rate , the original hydrocarbon generation potential index corresponding to the shale oil reservoir can be determined.

[0043] In a specific embodiment, the original hydrocarbon generation potential index corresponding to the shale oil reservoir is calculated in the following manner:

[0044] Calculate the first ratio between the pyrolysis hydrocarbon amount and the total organic carbon content, calculate the difference between 1 and the target hydrocarbon generation conversion rate, and determine the second ratio between the first ratio and the difference as the original hydrocarbon generation potential index corresponding to the shale oil reservoir.

[0045] In an example, the original hydrocarbon generation potential index corresponding to the shale oil reservoir is determined by the following formula .

[0046]

[0047] Preferably, the genetic types of crude oil accumulation include the retention type, in-source migration type, and micro-migration type.

[0048] In a preferred embodiment, the genetic type of crude oil accumulation corresponding to the shale oil reservoir is determined by the following formula:

[0049] Calculate 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, it is determined that the genetic type of crude oil accumulation corresponding to the shale oil reservoir is the in-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. According to the analysis results, the crude oil storage space and the organic matter enrichment location in the shale oil reservoir are determined. According to the crude oil storage space and the organic matter enrichment location in the shale oil reservoir, it is determined that the genetic type of crude oil accumulation corresponding to the shale oil reservoir is the retention type or the micro-migration type.

[0050] In a specific embodiment, calculate the second difference between the current hydrocarbon generation potential index and the original hydrocarbon generation potential index corresponding to the shale oil reservoir , according to determine whether there is macroscopic migration in the shale oil reservoir corresponding to the shale oil reservoir. When When >0, it is determined that there is macroscopic migration in the shale reservoir, and the genetic type of crude oil accumulation corresponding to the shale oil reservoir is determined to be in-source migration type. When <0, it is determined that There is basically no macroscopic migration, and the genetic type of crude oil accumulation corresponding to the shale oil reservoir is determined to be in-situ retention or micro-migration accumulation.

[0051] If it is determined that there is no macroscopic migration in the shale oil reservoir, then shale samples are selected for fluorescence thin section and laser confocal analysis to determine the crude oil storage space and the location of organic matter enrichment in the shale oil reservoir. According to the crude oil storage space and the location of organic matter enrichment, the vertical microscopic migration distance of hydrocarbon molecules is determined. Combining the distance interval where the vertical microscopic migration distance of hydrocarbon molecules is located, further determine whether the genetic type of crude oil accumulation corresponding to the shale oil reservoir is retention type or micro-migration type.

[0052] In a specific embodiment, based on fluorescence thin section and laser confocal analysis, the location of organic matter enrichment in the shale oil reservoir is determined, and then the vertical distance of the location of organic matter enrichment relative to the crude oil storage space is further calculated, and this vertical distance is determined as the vertical microscopic migration distance of hydrocarbon molecules.

[0053] In a preferred embodiment, the genetic type of crude oil accumulation corresponding to the shale oil reservoir is also determined by the following method:

[0054] If the vertical microscopic migration distance of hydrocarbon molecules is in the first distance interval, it is determined that the genetic type of crude oil accumulation corresponding to the shale oil reservoir is retention type. If it is determined that the vertical microscopic migration distance of hydrocarbon molecules is in the second distance interval, it is determined that the genetic type of crude oil accumulation corresponding to the shale oil reservoir is micro-migration type.

[0055] Specifically, the vertical microscopic migration distance of hydrocarbon molecules ranges from the nanometer level to the meter level, and the upper limit value of the first distance interval is less than the lower limit value of the second distance interval.

[0056] In step S200, the microscopic analysis of the laser confocal method performed in step S100 can be combined to obtain the crude oil storage space corresponding to the shale oil reservoir.

[0057] In step S300, the geological data includes at least reservoir lithology, mineral composition elements, and sedimentary structures. The reservoir types include matrix type, bedding type, laminar type, and interlayer type.

[0058] In a preferred embodiment, step S300 includes:

[0059] If the reservoir lithology is massive mudstone, the mineral composition elements are clay minerals, quartz, feldspar, and carbonate rock minerals, and the content of clay minerals is higher than the upper limit of the preset clay mineral content, the sedimentary structure is massive, and the main enrichment area corresponding to the crude oil is the pores of the mudstone matrix, it is determined that the shale oil reservoir is a matrix type reservoir.

[0060] If the reservoir lithology is shale, the mineral composition elements are clay minerals, quartz, and feldspar, and the content of clay minerals is higher than the upper limit of the preset clay mineral content, the main enrichment area of crude oil is the bedding fissures, and the sedimentary structure shows the development of book-like bedding, then it is determined that the shale oil reservoir is a bedding type reservoir.

[0061] If the reservoir lithology is laminated shale, the types of mineral composition elements exceed the preset quantity, the content of clay minerals is lower than the lower limit of the preset clay mineral content, the content of carbonate minerals exceeds the preset carbonate mineral content threshold, the main enrichment area of crude oil is the pores of the coarse clastic laminae, and the sedimentary structure indicates the interbedded development of clayey laminae and quartzofeldspathic laminae or carbonate laminae, then it is determined that the shale oil reservoir is a laminated type reservoir.

[0062] If the reservoir lithology is sandstone or carbonate thin layer within the shale oil reservoir series, and the main enrichment area of crude oil is the pores of the sandstone or carbonate interlayer, then it is determined that the shale oil reservoir is an interlayer type reservoir.

[0063] In this application, the upper limit of the preset clay mineral content can be 40%.

[0064] In a preferred embodiment, step S400 includes:

[0065] If the reservoir type corresponding to the shale oil reservoir is a matrix type reservoir or a bedding type reservoir, and the genetic type of crude oil accumulation is a retention type, then it is determined that the shale oil reservoir type corresponding to the shale oil reservoir is an in-situ retention type shale oil reservoir.

[0066] If the reservoir type corresponding to the shale oil reservoir is a laminated type reservoir, and the genetic type of crude oil accumulation is a micro-migration type, then it is determined that the shale oil reservoir type corresponding to the shale oil reservoir is a micro-migration laminated enrichment type shale oil reservoir.

[0067] If the reservoir type corresponding to the shale oil reservoir is an interlayer type reservoir, and the genetic type of crude oil accumulation is an in-source migration type, then it is determined that the shale oil reservoir type corresponding to the shale oil reservoir is an in-source migration interlayer enrichment type shale oil reservoir.

[0068] Please refer to Figure 3 , Figure 3 which shows a shale oil reservoir type discrimination chart provided by an embodiment of this application. As Figure 3In the shale oil reservoir type discrimination chart shown, the abscissa represents the vertical microscopic migration distance of hydrocarbon molecules. Different intervals of the vertical microscopic migration distance of hydrocarbon molecules correspond to different genetic types of crude oil accumulation. The first distance interval corresponds to the retention type, the second distance interval corresponds to the micro-migration type, and the third distance interval corresponds to the in-source migration type. The ordinate represents the sedimentary structure thickness corresponding to the shale oil reservoir. Different intervals of sedimentary structure thickness correspond to different reservoir types. The sedimentary structure thickness intervals corresponding to the matrix type reservoir and the bedding type reservoir are 0 to 1 mm (millimeter), the sedimentary structure thickness interval corresponding to the laminar type reservoir is 1 mm to 1 dm (decimeter), and the sedimentary structure thickness interval corresponding to the interlayer type reservoir is 1 dm to 5 m (meter). In this application, through the above method of this application combined with Figure 3 the shown shale oil reservoir type discrimination chart, the shale oil reservoir type can be further determined.

[0069] This application provides a shale oil reservoir type discrimination method that integrates macro-micro multi-scale and is mainly based on the differences in the origin of shale oil. It can reliably reveal the characteristics of shale oil reservoirs, improve the accuracy of shale oil reservoir type determination, and provide scientific guidance for subsequent resource / reserve calculation, exploration deployment, and development plan related to shale oil reservoir type, thereby improving the accuracy of subsequent analysis.

[0070] Based on the same inventive concept, in the embodiments of this application, there is also provided a discrimination device for shale oil reservoir type corresponding to the discrimination method for shale oil reservoir type provided in the above embodiments. Since the principle of solving problems by the device in the embodiments of this application is similar to the discrimination method for shale oil reservoir type in the above embodiments of this application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be elaborated.

[0071] Please refer to Figure 4 , Figure 4 which shows a functional module diagram of a discrimination device for shale oil reservoir type provided in the embodiments of this application. As Figure 4 shown, the device includes:

[0072] A first analysis module 500, configured to perform pyrolysis and total organic carbon content analysis on the pressure-maintained and sealed core of the shale oil reservoir in the study area, and determine the genetic type of crude oil accumulation corresponding to the shale oil reservoir based on the hydrocarbon generation potential discrimination method;

[0073] A second analysis module 510, configured to microscopically analyze and determine the crude oil storage space corresponding to the shale oil reservoir based on the laser confocal method;

[0074] A reservoir type determination module 520, which acquires the geological data and the 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;

[0075] The reservoir type determination module 530 is configured to determine the shale reservoir type based on the reservoir type corresponding to the shale oil reservoir and the crude oil accumulation genesis type.

[0076] Based on the same inventive concept, please refer to Figure 5 , Figure 5 which shows a schematic structural diagram of an electronic device provided by an embodiment of the present application. As Figure 5 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 runs, communication is carried out between the processor 610 and the memory 620 through the bus 630. When the machine-readable instructions are run by the processor 610, the steps of the discrimination method for the shale reservoir type provided in any of the above embodiments are executed.

[0077] Based on the same inventive concept, an embodiment of the present application also provides a computer-readable storage medium. A computer program is stored on the computer-readable storage medium. When the computer program is run by a processor, the steps of the discrimination method for the shale reservoir type provided in the above embodiment are executed.

[0078] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems and devices described above can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated herein. In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For another 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 couplings or direct couplings or communication connections shown or discussed with each other can be through some communication interfaces. The indirect couplings or communication connections of the devices or units can be in electrical, mechanical, or other forms.

[0079] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place, or they can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0080] In addition, in each embodiment of the present application, the functional units can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit.

[0081] When the above-mentioned functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium executable by a processor. Based on such understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a 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 and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The foregoing storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks, or optical discs.

[0082] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of changes or substitutions, which should all be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. A method for distinguishing shale reservoir types, characterized in that: The method comprises: Conduct pyrolysis and total organic carbon content analysis on the pressure-maintained sealed core corresponding to the shale oil reservoir in the study area, determine the pyrolysis and total organic carbon parameters corresponding to the shale oil reservoir, determine the current hydrocarbon generation potential index and the original hydrocarbon generation potential index corresponding to the shale oil reservoir based on the pyrolysis and total organic carbon parameters, and determine the crude oil accumulation genesis type corresponding to the shale oil reservoir based on the current hydrocarbon generation potential index and the original hydrocarbon generation potential index; 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; Determine the type of shale oil reservoir based on the reservoir type and crude oil accumulation genesis type corresponding to the shale oil reservoir; 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.

2. The method according to claim 1, 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.

3. The method according to claim 2, 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.

4. The method according to claim 3, 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 formula: In this formula, Represents the original hydrocarbon generation potential index corresponding to the shale oil reservoir, represents the amount of thermal cracking hydrocarbons, represents the total organic carbon content, Represents the target hydrocarbon conversion rate.

5. The method according to claim 1, 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.

6. 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.

7. 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.

8. 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-maintaining sealed core corresponding to the shale oil reservoir in the study area, determine the pyrolysis and total organic carbon parameters corresponding to the shale oil reservoir, determine the current hydrocarbon generation potential index and the original hydrocarbon generation potential index corresponding to the shale oil reservoir based on the pyrolysis and total organic carbon parameters, and determine the crude oil accumulation genesis type corresponding to the shale oil reservoir according to the current hydrocarbon generation potential index and the original hydrocarbon generation potential index; 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; An oil reservoir type determination module, 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; The types of crude oil accumulation in the shale oil reservoir include retention type, intra-source migration type and micro-migration type, wherein the first analysis module is further used for: 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.

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