Feature characterization method and apparatus for continental shale oil, and electronic device and storage medium

Abstract

The present disclosure relates to the technical field of petroleum. Provided are a feature characterization method and apparatus for continental shale oil, and an electronic device and a storage medium. The method comprises: acquiring feature data of aged continental shale samples in a first dimension and a second dimension, and acquiring feature data of fresh continental shale samples in the first dimension; and on the basis of the feature data of the aged continental shale samples in the first dimension and the second dimension, and the feature data of the fresh continental shale samples in the first dimension, using cryogenic focused ion beam-scanning electron microscopy imaging technology to perform feature characterization on the fresh continental shale samples, in order to acquire feature data of the fresh continental shale samples in a third dimension, wherein the third dimension comprises at least one of occurrence features, main controlling factors and effective oil storage space. The feature characterization method and apparatus for continental shale oil, and the electronic device and the storage medium provided in the present disclosure enable more accurate acquisition of feature data of fresh continental shale in a dimension comprising at least one of occurrence features, main controlling factors and effective oil storage space.

Description

Characterization methods, devices, electronic equipment, and storage media for continental shale oil

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202510361033.7, filed on March 26, 2025, entitled “Method, Apparatus, Electronic Device and Storage Medium for Characterizing Characteristics of Continental Shale Oil”, which is incorporated herein by reference in its entirety. Technical Field

[0003] This disclosure relates to the field of petroleum technology, and in particular to a method, apparatus, electronic device, and storage medium for characterizing continental shale oil. Background Technology

[0004] The occurrence characteristics, key controlling factors, and effective oil storage space of shale oil are crucial for evaluating its resource potential, development difficulty, and economic feasibility. Characterizing these characteristics provides a data foundation for shale oil exploration, development, and production.

[0005] Continental shale oil refers to petroleum resources found in shale formations within continental sedimentary environments (such as lacustrine and riverine environments). Compared to marine shale oil (such as North American shale oil), continental shale oil is found in shale formations characterized by multi-source mixing, integrated source and reservoir, thin-layer stacking, overall oil content, and localized enrichment. The complex lithofacies and variable petroleum evolution processes make it challenging to characterize the occurrence characteristics, controlling factors, and effective oil storage space of continental shale oil. In related technologies, characterization results often differ significantly from actual conditions, hindering accurate characterization and thus limiting the exploration and development of continental shale oil.

[0006] Therefore, how to more accurately characterize the features of shale oil is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0007] This disclosure provides a method, apparatus, electronic device, and storage medium for characterizing continental shale oil, which addresses the shortcomings of related technologies in accurately characterizing the occurrence characteristics, main controlling factors, and effective oil storage space of shale oil.

[0008] This disclosure provides a method for characterizing continental shale oil, including:

[0009] The method involves acquiring characteristic data for the first and second dimensions of aged continental shale samples, and acquiring characteristic data for the first dimension of fresh continental shale samples. The aged continental shale samples are obtained in the target subsurface area using pressure-holding coring technology and are then stored in a normal temperature and pressure environment for more than a first preset time. The fresh continental shale samples are obtained in the target subsurface area using pressure-holding coring technology and are then stored in a low-temperature environment for no more than a second preset time, wherein the fresh continental shale samples are isolated from air during storage in the low-temperature environment. The first dimension includes at least one of lithology type, lithofacies type, and maturity. The second dimension includes at least one of total organic carbon content and / or mineral assemblage.

[0010] Based on the first and second dimension feature data of the aged continental shale sample and the first dimension feature data of the fresh continental shale sample, the fresh continental shale sample is characterized using cryo-focused ion beam scanning electron microscopy imaging technology to obtain the third dimension feature data of the fresh continental shale sample; the third dimension includes at least one of occurrence characteristics, main controlling factors, and effective oil storage space.

[0011] According to the continental shale oil characteristic characterization method provided in this disclosure, the method involves characterizing the fresh continental shale sample based on the first and second dimension characteristic data of the aged continental shale sample and the first dimension characteristic data of the fresh continental shale sample using cryo-focused ion beam scanning electron microscopy imaging technology to obtain the third dimension characteristic data of the fresh continental shale sample, including:

[0012] A portion of the fresh continental shale sample was sliced ​​to obtain a slice of the fresh continental shale sample, and an image of the slice of the fresh continental shale sample was obtained.

[0013] Based on the first dimension feature data of the fresh continental shale sample, a first region localization model corresponding to the fresh continental shale sample is determined. The first region localization model corresponding to the fresh continental shale sample is obtained after training based on the second dimension feature data of the sample-stored continental shale sample and the location information of the first region of interest on the slice of the sample-stored continental shale sample. The first dimension feature data of the sample-stored continental shale sample is matched with the first dimension feature data of the fresh continental shale sample. The stored continental shale sample includes the sample-stored continental shale sample. The slice of the sample-stored continental shale sample is obtained by slicing a portion of the sample-stored continental shale sample.

[0014] The image of the fresh continental shale sample slice is input into the first region localization model corresponding to the fresh continental shale sample to obtain the location information of the first region of interest on the fresh continental shale sample slice output by the first region localization model corresponding to the fresh continental shale sample.

[0015] Based on the location information of the first region of interest on the fresh continental shale sample slice, two-dimensional imaging characterization is performed on the first region of interest on the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy, and then the feature data of the third dimension of the fresh continental shale sample is obtained based on the two-dimensional imaging characterization results.

[0016] According to the method for characterizing continental shale oil provided in this disclosure, after acquiring the image of the fresh continental shale sample slice, the method further includes:

[0017] Based on the feature data of the first dimension of the fresh continental shale sample, a second region of interest localization model corresponding to the fresh continental shale sample is determined. The second region of interest localization model corresponding to the fresh continental shale sample is obtained after training based on the feature data of the second dimension of the sample-arranged continental shale sample and the location information of the second region of interest on the slice of the sample-arranged continental shale sample.

[0018] The image of the fresh continental shale sample slice is input into the second region of interest localization model corresponding to the fresh continental shale sample to obtain the location information of the second region of interest on the fresh continental shale sample slice output by the second region of interest localization model corresponding to the fresh continental shale sample.

[0019] Based on the location information of the second region of interest on the fresh continental shale sample slice, the second region of interest on the fresh continental shale sample slice is characterized by three-dimensional imaging using cryo-focused ion beam scanning electron microscopy imaging technology. Then, based on the three-dimensional imaging characterization results, the feature data of the third dimension of the fresh continental shale sample are obtained.

[0020] According to the method for characterizing continental shale oil provided in this disclosure, the step of performing two-dimensional imaging characterization of the first region of interest on the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy based on the location information of the first region of interest on the fresh continental shale sample slice includes:

[0021] The fresh continental shale sample slices were pretreated to obtain pretreated fresh continental shale sample slices.

[0022] In a frozen state, the pretreated fresh terrestrial shale sample slice is transferred into the sample chamber of a cryo-focused ion beam scanning electron microscope, and multiple two-dimensional fresh surfaces are etched on the first region of interest on the pretreated fresh terrestrial shale sample slice using a focused ion beam at a first temperature.

[0023] The scanning electron microscope image of the fresh surface is obtained using the cryo-focused ion beam scanning electron microscope as the two-dimensional imaging characterization result. The chemical composition data of the fresh surface is obtained using the energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope as the two-dimensional imaging characterization result.

[0024] The pretreated fresh terrestrial shale sample slices are heated to a second temperature. At the second temperature, a scanning electron microscope image of the fresh surface is acquired again using a scanning electron microscope as the two-dimensional imaging characterization result. The chemical composition data of the fresh surface is acquired again using the energy dispersive spectrometer mounted on the scanning electron microscope as the two-dimensional imaging characterization result.

[0025] According to the continental shale oil characteristic characterization method provided in this disclosure, the step of performing three-dimensional imaging characterization of the second region of interest on the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy imaging technology within the second region of interest on the fresh continental shale sample slice, based on the location information of the second region of interest, includes:

[0026] At the first temperature, a cube of the target size is obtained by etching the second region of interest on the pretreated fresh terrestrial shale sample slice using a focused ion beam;

[0027] At the first temperature, the cube is sliced ​​with a preset thickness using a focused ion beam. The scanning electron microscope image of each cube slice is obtained using the cryo-focused ion beam scanning electron microscope. The chemical composition data of each cube slice is obtained using the energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope. The number of each cube slice is a preset number.

[0028] Three-dimensional skeleton modeling is performed based on the scanning electron microscope images of each cube slice to obtain a three-dimensional skeleton model of the cube. Based on the chemical composition data of each cube slice, a pore space structure is generated in the three-dimensional skeleton model of the cube to obtain a three-dimensional model of the cube, which serves as the three-dimensional imaging characterization result.

[0029] According to the method for characterizing continental shale oil provided in this disclosure, the fresh continental shale sample is obtained through the following steps: after obtaining the continental shale sample from the target underground area by pressure-holding coring technology, a protective layer for isolating air is coated on the surface of the continental shale sample.

[0030] After the protective layer is applied to the surface of the continental shale sample, the continental shale sample with the protective layer is stored in dry ice.

[0031] If the preservation time of the continental shale sample covered with the protective layer in dry ice does not exceed the second preset time, the continental shale sample is identified as the fresh continental shale sample.

[0032] This disclosure also provides a characterization device for continental shale oil, comprising:

[0033] The data acquisition module is used to acquire feature data of the first and second dimensions of aged continental shale samples, and to acquire feature data of the first dimension of fresh continental shale samples. The aged continental shale samples are obtained in the target underground area using pressure-holding coring technology and are then stored in a normal temperature and pressure environment for more than a first preset time. The fresh continental shale samples are obtained in the target underground area using pressure-holding coring technology and are then stored in a low-temperature environment for no more than a second preset time, wherein the fresh continental shale samples are isolated from air during storage in the low-temperature environment. The first dimension includes at least one of lithology type, lithofacies type, and maturity. The second dimension includes at least one of total organic carbon content and / or mineral assemblage.

[0034] The feature characterization module is used to characterize the fresh continental shale sample based on the feature data of the first and second dimensions of the aged continental shale sample and the feature data of the first dimension of the fresh continental shale sample using cryo-focused ion beam scanning electron microscopy imaging technology, and to obtain the feature data of the third dimension of the fresh continental shale sample; the third dimension includes at least one of occurrence characteristics, main controlling factors and effective oil storage space.

[0035] This disclosure also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement any of the above-described methods for characterizing continental shale oil features.

[0036] This disclosure also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the continental shale oil characterization method as described above.

[0037] This disclosure also provides a computer program product, including a computer program that, when executed by a processor, implements any of the above-described methods for characterizing continental shale oil features.

[0038] The method, apparatus, electronic equipment, and storage medium for characterizing continental shale oil disclosed herein preserve fresh continental shale samples obtained using pressure-holding coring technology in a low-temperature, air-isolated environment before characterization. This maximizes the preservation of the physical and chemical properties of the fresh continental shale samples, keeping them as close as possible to their original state, thus improving the accuracy of subsequent characterization. It can utilize the first and second dimension characteristic data of aged continental shale samples preserved at room temperature for a long period to provide data guidance for characterizing fresh continental shale samples. Furthermore, it can utilize the high-resolution three-dimensional imaging technology of cryo-focused ion beam scanning electron microscopy to achieve in-situ imaging characterization of fresh continental shale samples. This allows for more accurate acquisition of at least one dimension of characteristic data in fresh continental shale, including its occurrence characteristics, main controlling factors, and effective oil-bearing space. It effectively overcomes the data distortion bottleneck caused by sample degradation in traditional characterization methods, providing a more accurate data foundation for shale oil exploration, development, and production, and has significant guiding significance for the formulation of shale oil exploration and development plans. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in this disclosure or related technologies, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 is a flowchart illustrating the characterization method for continental shale oil provided in this disclosure.

[0041] Figure 2 is a scanning electron microscope image of a cube etched into a pre-treated fresh continental shale sample slice in the continental shale oil characterization method provided in this disclosure.

[0042] Figure 3 is a schematic diagram of the structure of the continental shale oil characterization device provided in this disclosure.

[0043] Figure 4 is a schematic diagram of the structure of the electronic device provided in this disclosure. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this disclosure clearer, the technical solutions of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0045] It should be noted that as oil is the core of the global energy system, the depletion of conventional crude oil reserves makes the exploration of unconventional oil resources crucial. Shale oil refers to oil resources stored in shale formations, including oil in the pores and fractures of mudstone and shale, as well as oil in adjacent and interlayered layers of tight carbonate or clastic rocks within mudstone and shale formations. As an unconventional oil resource, the exploration and development of shale oil is of great significance for optimizing the energy structure and ensuring energy security.

[0046] The occurrence characteristics of shale oil refer to its distribution state, phase state, and interaction with rocks in underground reservoirs. The occurrence characteristics of shale oil mainly include occurrence phase state, distribution characteristics, and occurrence space.

[0047] The controlling factors of shale oil refer to the factors that have a decisive influence on the formation, enrichment, storage, and exploitation of shale oil. The controlling factors of shale oil may include, but are not limited to, organic matter characteristics, mineral composition, reservoir properties, temperature and pressure conditions, and tectonic setting.

[0048] The effective reservoir space of shale oil refers to the pore and fracture system within shale that can store and allow oil and gas to flow. The effective reservoir space of shale oil mainly includes organic matter pores, inorganic mineral pores, microfracture networks, and dissolution voids.

[0049] The occurrence characteristics, main controlling factors, and effective oil storage space of shale oil are key to evaluating the resource potential, development difficulty, and economic feasibility of shale oil.

[0050] Traditional methods for characterizing continental shale oil in related technologies can utilize physicochemical characterization techniques (such as rock pyrolysis or nuclear magnetic resonance) or microscopic imaging techniques (such as conventional field emission scanning electron microscopy or focused ion beam scanning electron microscopy) to characterize the features of continental shale oil. However, shale, originally situated in a high-temperature and high-pressure underground environment (temperature 60-200℃, pressure 10-100MPa), undergoes significant migration and loss of hydrocarbons in the cored shale samples after being transferred to the surface environment (temperature 25℃, pressure 101.3KPa) due to the drastic change in environmental conditions. This makes it difficult to accurately characterize the features of continental shale oil using the aforementioned physicochemical characterization techniques.

[0051] Characterizing continental shale samples using microscopic imaging techniques requires imaging the freshly polished surface of the shale sample under a high vacuum environment. However, liquid hydrocarbons on the freshly polished surface of the shale sample are unstable and easily escape in a high vacuum environment, leading to significant discrepancies between the characterization results obtained from microscopic imaging techniques and the actual situation. Therefore, how to more accurately characterize the features of shale oil is a technical problem that urgently needs to be solved in this field.

[0052] To address this issue, this disclosure provides a method for characterizing continental shale oil. This method innovatively establishes an experimental procedure for in-situ imaging of continental shale samples, promoting the development of in-situ imaging characterization technology for shale oil. It has significant guiding significance for deepening the understanding of in-situ geological theory of continental shale oil and formulating development strategies. The method for characterizing continental shale oil provided in this disclosure is described below with reference to Figures 1-2.

[0053] Figure 1 is a flowchart illustrating the characterization method for continental shale oil provided in this disclosure. As shown in Figure 1, the method includes the following:

[0054] Step 101: Obtain the first and second dimension feature data of the aged continental shale sample, and obtain the first dimension feature data of the fresh continental shale sample; the aged continental shale sample was obtained in the target underground area using pressure-holding coring technology, and was stored in a normal temperature and pressure environment for more than a first preset time after acquisition; the fresh continental shale sample was obtained in the target underground area using pressure-holding coring technology, and was stored in a low temperature environment for no more than a second preset time after acquisition, and the fresh continental shale sample was isolated from air during storage in the low temperature environment; the first dimension includes at least one of lithology type, lithofacies type and maturity; the second dimension includes at least one of total organic carbon content and / or mineral assemblage.

[0055] It should be noted that the execution subject of this embodiment is a continental shale oil characterization device. This continental shale oil characterization device can be configured in electronic devices such as computers or servers.

[0056] Specifically, fresh continental shale samples are the characteristic characterization objects of the continental shale oil characteristic characterization method provided in this disclosure. Based on the continental shale oil characteristic characterization method provided in this disclosure, the third-dimensional characteristic data of fresh continental shale samples can be obtained.

[0057] It should be noted that the first and second preset durations in the two embodiments of this disclosure can be determined based on prior knowledge and / or actual circumstances. For example, the value of the first preset duration can range from 80 to 100 days; the value of the second preset duration can range from 6 to 8 days. The specific values ​​of the first and second preset durations are not limited in the embodiments of this disclosure.

[0058] It should be noted that the ambient temperature and pressure values ​​in this embodiment refer to room temperature (25°C) and atmospheric pressure (101.3 kPa). The temperature of the low-temperature environment in this embodiment can be determined based on prior knowledge and / or actual conditions, and this embodiment does not specifically limit the temperature of the aforementioned low-temperature environment.

[0059] It is understood that in the embodiments of this disclosure, the number of stored continental shale samples is multiple, and the number of fresh continental shale samples may be one or more.

[0060] As an alternative embodiment, fresh terrestrial shale samples are obtained by the following steps: after obtaining terrestrial shale samples from the target subsurface area using pressure-controlled coring technology, a protective layer is applied to the surface of the terrestrial shale samples to isolate them from air.

[0061] It should be noted that pressure-maintaining coring is a drilling coring technique that maintains or approaches the original formation pressure during the coring process. It is primarily used to obtain subsurface core samples and ensure that fluid components such as oil, gas, and water within the core are not lost during coring, thus accurately reflecting the original state of the formation. When obtaining core samples using pressure-maintaining coring, pressure compensation devices (such as high-pressure gas chambers and regulating valves) are used to maintain the formation pressure inside the core during coring, preventing the escape of gases and light components due to pressure reduction. A sealing fluid (such as calcium carbonate or calcium bromide) is used to coat the core surface to prevent drilling fluid contamination. Simultaneously, a ball valve mechanism seals the core casing after coring, ensuring the core remains sealed during hoisting. During tripping, high-pressure nitrogen or inert gas is used to replenish pressure to the inner core casing, maintaining a constant internal pressure and ensuring the core retains its original formation pressure before surface processing.

[0062] It should be noted that the target underground area in this embodiment can be determined based on actual needs. This embodiment does not specifically limit the target underground area.

[0063] It is understood that the preserved terrestrial shale samples and fresh terrestrial shale samples in the embodiments of this disclosure are terrestrial shale samples taken from the same underground area but with different preservation methods and preservation times.

[0064] After obtaining terrestrial shale samples from the target underground area using pressure-holding coring technology, a protective layer for isolating air can be applied to the surface of the terrestrial shale samples within a third preset time period.

[0065] It should be noted that the third preset duration in this embodiment can be determined based on prior knowledge and / or actual conditions. For example, the value of the third preset duration can range from 20 seconds to 40 seconds. This embodiment does not limit the specific value of the aforementioned third preset duration.

[0066] Optionally, in the embodiments of this disclosure, the protective layer used to cover the above-mentioned terrestrial shale sample can be a polyethylene film, a paraffin film, a polyvinyl chloride film or a polyester film, as well as a paraffin coating or a silicone coating.

[0067] After coating the surface of the terrestrial shale sample with a protective layer, the coated terrestrial shale sample was stored in dry ice.

[0068] Specifically, after the surface of the aforementioned terrestrial shale sample is covered with a protective layer for isolating space, the terrestrial shale sample covered with the protective layer can be placed in a low-temperature freezer containing dry ice within a fourth preset time period, and then the terrestrial shale sample in the low-temperature environment can be transported to the laboratory under cold chain conditions.

[0069] It should be noted that the fourth preset duration in this embodiment can be determined based on prior knowledge and / or actual circumstances. For example, the value of the fourth preset duration can range from 20 seconds to 40 seconds. This embodiment does not limit the specific value of the fourth preset duration.

[0070] It is understood that the sublimation temperature of dry ice is -78.5°C. Therefore, when the terrestrial shale sample with the protective layer described above is stored in a low-temperature environment, the temperature of the low-temperature environment is -78.5°C.

[0071] If the preservation time of the continental shale sample covered with a protective layer in dry ice does not exceed the second preset time, the continental shale sample is identified as a fresh continental shale sample.

[0072] It should be noted that the preservation time of the aforementioned continental shale samples coated with protective layers in dry ice is counted from the moment the aforementioned continental shale samples coated with protective layers are placed in the dry ice.

[0073] As an optional embodiment, the aged continental shale sample is obtained through the following steps: after obtaining the continental shale sample from the target underground area using pressure-controlled coring technology, the continental shale sample is stored in a normal temperature and pressure environment. If the duration of storage of the continental shale sample in the normal temperature and pressure environment exceeds a first preset duration, the continental shale sample is identified as an aged continental shale sample.

[0074] It should be noted that the preservation time of the above-mentioned terrestrial shale samples in a normal temperature and pressure environment is calculated from the moment the terrestrial shale samples are placed in the normal temperature and pressure environment.

[0075] In this embodiment of the disclosure, characteristic data of the first and second dimensions of the aged continental shale sample can be obtained by testing and analyzing a portion of the sample.

[0076] It should be noted that, in this disclosure, the total organic carbon (TOC) content refers to the abundance of organic matter in shale, which is generally proportional to the oil and gas potential of shale. Maturity reflects the degree of thermal evolution of shale; high maturity usually means that shale has a high oil and gas generation potential. Mineral assemblage can affect the pore structure and oil and gas occurrence state of shale. Lithological classification includes mudstone and shale, etc., affecting the occurrence state and distribution of oil and gas in shale. Shales with different lithofacies classifications have different pore characteristics and oil and gas occurrence capabilities.

[0077] Specifically, geochemical analysis can be performed on some samples of aged continental shale, including rock pyrolysis, total organic carbon (TOC) measurement, and vitrinite reflectance (Ro) analysis, to obtain the total organic carbon content and maturity of the aged continental shale samples.

[0078] We can also take some samples from the aged continental shale samples for petrological and mineralogical characterization to determine the lithofacies type of the aged continental shale samples.

[0079] Alternatively, a portion of the aged terrestrial shale sample can be sliced ​​to obtain a 20 μm thick thin section. This thin section can then be analyzed using a Zeiss Axio Scope A2 polarizing microscope to determine the lithological type of the aged terrestrial shale sample and distinguish whether it is coarse-grained siltstone or fine-grained shale (coarse-grained siltstone has a mineral grain size greater than 62.5 μm).

[0080] The mineral composition of the above-mentioned aged terrestrial shale samples can be obtained by testing thin sections of the samples using X-ray diffraction (XRD) technology.

[0081] It should be noted that quantitative separation of group composition and chromatographic analysis of saturated hydrocarbons in crude oil produced in the target underground area can obtain characteristic data such as chemical composition, crude oil type, crude oil fluidity and processing performance, molecular composition of saturated hydrocarbons in crude oil, crude oil maturity, degree of biodegradation of crude oil, source of organic matter and sedimentary environment characteristics of crude oil produced in the target underground area.

[0082] It should be noted that when obtaining the above-mentioned aged continental shale samples using the pressure-holding coring technique, the volatile gases produced can be collected, and then analyzed using headspace gas chromatography-mass spectrometry (HS-GC-MS) to obtain the composition of volatile hydrocarbons in the above-mentioned aged continental shale samples.

[0083] In this embodiment of the disclosure, characteristic data of the first dimension of the fresh continental shale sample can be obtained by testing and analyzing a portion of the sample.

[0084] It should be noted that the method for obtaining the first dimension feature data of fresh continental shale samples is the same as the method for obtaining the first dimension feature data of aged continental shale samples, and will not be repeated in this embodiment.

[0085] Step 102: Based on the first and second dimension feature data of the aged continental shale sample and the first dimension feature data of the fresh continental shale sample, the fresh continental shale sample is characterized by cryo-focused ion beam scanning electron microscopy imaging technology to obtain the third dimension feature data of the fresh continental shale sample; the third dimension includes at least one of occurrence characteristics, main controlling factors and effective oil storage space.

[0086] It should be noted that cryo-focused ion beam scanning electron microscopy imaging technology (Cryo-FIB-SEM) is an advanced technology that combines cryogenic freezing, focused ion beam (FIB) cutting, and scanning electron microscopy (SEM) imaging. It is mainly used to perform high-resolution three-dimensional imaging of samples in near-natural conditions.

[0087] After obtaining the first and second dimension feature data of aged continental shale samples and the first dimension feature data of fresh continental shale samples, the first dimension feature data of the fresh continental shale samples can be characterized using cryo-focused ion beam scanning electron microscopy imaging technology, through at least one of numerical calculation, mathematical statistics, conditional judgment, and deep learning techniques, to obtain the third dimension feature data of the fresh continental shale samples.

[0088] This embodiment preserves fresh continental shale samples obtained using pressure-holding coring technology in a low-temperature, air-isolated environment before characterization. This maximizes the preservation of the physical and chemical properties of the fresh continental shale samples, keeping them as close as possible to their original state, thus improving the accuracy of subsequent characterization. It utilizes the first and second dimension characteristic data of long-term preserved continental shale samples at room temperature to provide data guidance for characterizing fresh continental shale samples. Furthermore, it leverages the high-resolution three-dimensional imaging technology of cryo-focused ion beam scanning electron microscopy to achieve in-situ imaging characterization of fresh continental shale samples. This allows for more accurate acquisition of at least one dimension of characteristic data regarding the occurrence characteristics, controlling factors, and effective oil-bearing space of fresh continental shale. It effectively overcomes the data distortion bottleneck caused by sample degradation in traditional characterization methods, providing a more accurate data foundation for shale oil exploration, development, and production, and has significant guiding significance for the formulation of shale oil exploration and development plans.

[0089] As an optional embodiment, based on the first and second dimension feature data of the stored continental shale sample and the first dimension feature data of the fresh continental shale sample, the fresh continental shale sample is characterized using cryo-focused ion beam scanning electron microscopy imaging technology to obtain the third dimension feature data of the fresh continental shale sample. This includes: taking a portion of the fresh continental shale sample for slicing, obtaining slices of the fresh continental shale sample, and obtaining images of the slices of the fresh continental shale sample.

[0090] Specifically, in this embodiment of the present disclosure, a portion of a fresh continental shale sample can be mechanically crushed and sliced ​​in a liquid nitrogen freezing environment (-196°C) to obtain a fresh continental shale sample slice with a length × width × thickness of approximately 5 mm × 5 mm × 1 mm.

[0091] Similarly, in the embodiments of this disclosure, the slices of the aged terrestrial shale sample are obtained by mechanically crushing and slicing a portion of the aged terrestrial shale sample in a liquid nitrogen freezing environment (-196°C). The size of the slices of the aged terrestrial shale sample is approximately 5mm × 5mm × 1mm.

[0092] It is understood that in the embodiments of this disclosure, there are multiple fresh continental shale sample slices and multiple aged continental shale sample slices.

[0093] After obtaining fresh and aged continental shale sample slices, both samples were cryopreserved in liquid nitrogen.

[0094] After obtaining fresh continental shale sample slices, imaging equipment such as optical microscopes, scanning electron microscopes, or yard microscopes can be used to obtain images of the fresh continental shale sample slices.

[0095] It should be noted that the images of the stored continental shale sample slices were obtained using the same imaging equipment as those used to obtain images of fresh continental shale sample slices.

[0096] It should be noted that the first region of interest in this embodiment is a region on a continental shale sample slice suitable for two-dimensional imaging characterization. The second region of interest in this embodiment is a region on a continental shale sample slice suitable for three-dimensional imaging characterization.

[0097] Accordingly, after acquiring images of the aged continental shale sample slices, key features in the images, such as porosity, pore morphology, mineral distribution, micro-fracture characteristics, and spatial structure, can be obtained. Then, based on these key features, an algorithm can be used to select regions with high total organic carbon content, relatively good maturity, and good pore structure, suitable for two-dimensional imaging, as the first region of interest (ROI). Similarly, regions with high ROI content, relatively good maturity, and good pore structure, suitable for three-dimensional imaging, can be selected as the second region of interest (ROI). Finally, based on the location information of the first and second ROI regions in the images, and the mapping relationship between the images and the aged continental shale sample slices, the location information of the first and second ROI regions in the aged continental shale sample slices can be obtained.

[0098] Based on the first-dimensional feature data of fresh continental shale samples, a first-region localization model corresponding to the fresh continental shale samples is determined. This first-region localization model is obtained after training based on the second-dimensional feature data of the sample-stored continental shale samples and the location information of the first region of interest on the slices of the sample-stored continental shale samples. The first-dimensional feature data of the sample-stored continental shale samples is matched with the first-dimensional feature data of the fresh continental shale samples. The stored continental shale samples include the sample-stored continental shale samples. The slices of the sample-stored continental shale samples are obtained by slicing a portion of the sample-stored continental shale samples.

[0099] It should be noted that, in this embodiment of the present disclosure, the aged continental shale samples can be grouped based on the first dimension feature data of the aged continental shale samples. Aged continental shale samples with the same lithofacies type can be grouped into one group, aged continental shale samples with the same lithological type can be grouped into another group, and aged continental shale samples with maturity belonging to the same preset maturity range can be grouped into another group, thus obtaining multiple first-order aged continental shale sample groups.

[0100] The aforementioned preset maturity range can be determined based on prior knowledge and / or actual conditions. There can be multiple preset maturity ranges; for example, the preset maturity ranges may include [0.5%, 1.5%) and [1.5%, 2.5%). This disclosure does not specifically limit the aforementioned preset maturity ranges.

[0101] It should be noted that the terrestrial shale samples included in different first-order terrestrial shale sample groups can be repeated.

[0102] After obtaining multiple primary-stage continental shale sample groups, these primary-stage continental shale sample groups can be arranged and combined. Each combination of multiple primary-stage continental shale sample groups can be identified as a secondary-stage continental shale sample group. This allows for the acquisition of secondary-stage continental shale sample groups with the same lithofacies and lithological types, secondary-stage continental shale sample groups with the same lithofacies and maturity within the same preset maturity range, secondary-stage continental shale sample groups with the same lithological types and maturity within the same preset maturity range, and secondary-stage continental shale sample groups with the same lithofacies, lithological types, and maturity within the same preset maturity range.

[0103] For each first-order settled continental shale sample group, the second-dimensional feature data of the settled continental shale samples in the first-order settled continental shale sample group can be used as training samples, and the location information of the first region of interest on the settled continental shale sample slices in the first-order settled continental shale sample group can be used as sample labels to train the first initial model, thereby obtaining the first regional localization model corresponding to the first-order settled continental shale sample group.

[0104] For each secondary-level terrestrial shale sample group, the second-dimensional feature data of each terrestrial shale sample in the secondary-level terrestrial shale sample group can be used as training samples, and the location information of the first region of interest on the terrestrial shale sample slice of each terrestrial shale sample in the secondary-level terrestrial shale sample group can be used as sample labels to train the first initial model, thereby obtaining the first regional localization model corresponding to the secondary-level terrestrial shale sample group.

[0105] It should be noted that the first initial model in this embodiment can be constructed based on supervised learning algorithms, such as support vector machine (SVM), random forest (RF) and artificial neural network (ANN). The first initial model in this embodiment can also be constructed based on deep learning algorithms, such as convolutional neural network (CNN) or generative adversarial network (GANs).

[0106] After obtaining the first-dimensional feature data of the fresh continental shale sample, the first-level or second-level aged continental shale sample group whose first-dimensional feature data matches the first-dimensional feature data of the fresh continental shale sample can be selected as the aged continental shale sample group corresponding to the fresh continental shale sample. The first regional positioning model corresponding to the aged continental shale sample group corresponding to the fresh continental shale sample is determined as the first regional positioning model corresponding to the fresh continental shale sample group. The aged continental shale samples in the aged continental shale sample group corresponding to the fresh continental shale sample are determined as the sample aged continental shale samples.

[0107] It is understandable that the first-dimensional feature data of the stored continental shale sample matches the first-dimensional feature data of the fresh continental shale sample.

[0108] It should be noted that the conditions for determining whether the characteristic data of the first dimension of a fresh continental shale sample matches the characteristic data of the first dimension of an aged continental shale sample include: the lithofacies type of the fresh continental shale sample is the same as that of the aged continental shale sample; the lithology of the fresh continental shale sample is the same as that of the aged continental shale sample; and the maturity of the fresh continental shale sample and the maturity of the aged continental shale sample belong to at least one of the same preset maturity range. The specific content of the above conditions corresponds one-to-one with the data dimensions included in the first dimension.

[0109] For example, if the first dimension includes lithology or lithofacies type, if the lithofacies type of the fresh continental shale sample is the same as that of the aged continental shale sample, or if the lithology type of the fresh continental shale is the same as that of the aged continental shale sample, then it can be determined that the characteristic data of the first dimension of the fresh continental shale sample matches the characteristic data of the first dimension of the aged continental shale sample.

[0110] For example, if the first dimension includes lithology type, lithofacies type, and maturity, and the lithofacies type of the fresh continental shale sample is the same as that of the aged continental shale sample, and the lithology type of the fresh continental shale is the same as that of the aged continental shale sample, and the maturity of the fresh continental shale and the maturity of the aged continental shale sample belong to the same preset maturity range, then...

[0111] The image of a slice of fresh continental shale sample is input into the localization model of the first region corresponding to the fresh continental shale sample, and the location information of the first region of interest on the slice of fresh continental shale sample is obtained from the localization model of the first region corresponding to the fresh continental shale sample.

[0112] Specifically, after determining the first region localization model corresponding to the fresh continental shale sample, the image of the fresh continental shale sample slice can be input into the first region localization model. The first region localization model can extract key features such as porosity, pore morphology, mineral distribution, micro-fracture characteristics, and spatial structure characteristics from the image of the fresh continental shale sample slice. Based on these key features, the first region of interest can be determined in the image of the fresh continental shale sample slice. Furthermore, based on the mapping relationship between the image of the fresh continental shale sample slice and the fresh continental shale sample slice, the location information of the first region of interest on the fresh continental shale sample slice can be obtained and output.

[0113] Based on the location information of the first region of interest on the slice of fresh continental shale sample, two-dimensional imaging characterization is performed in the first region of interest on the slice of fresh continental shale sample using cryo-focused ion beam scanning electron microscopy. Then, based on the two-dimensional imaging characterization results, the third-dimensional feature data of the fresh continental shale sample is obtained.

[0114] Specifically, after obtaining the location information of the first region of interest on the fresh continental shale sample slice output by the first region localization model corresponding to the fresh continental shale sample, two-dimensional imaging characterization can be performed within the first region of interest of the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy. One or more two-dimensional imaging characterization results can be obtained. Then, based on the above two-dimensional imaging characterization results, the third-dimensional feature data of the fresh continental shale sample can be obtained through numerical calculation, mathematical statistics, and deep learning techniques.

[0115] As an optional embodiment, based on the location information of the first region of interest on the fresh continental shale sample slice, two-dimensional imaging characterization is performed on the first region of interest on the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy imaging technology, including: preprocessing the fresh continental shale sample slice to obtain a preprocessed fresh continental shale sample slice.

[0116] Specifically, fresh continental shale sample slices were securely mounted on the stage of a cryo-focused ion beam scanning electron microscope using mechanical clamps. The stage carrying the fresh continental shale sample slices was then cryogenically transferred to a Leica EM VCT500 vacuum cryo-transfer system and stabilized at liquid nitrogen temperature. Subsequently, the fresh continental shale sample slices were transferred through the cryo-transfer chamber of the Leica EM VCT500 vacuum cryo-transfer system to a Leica EM ACE200 cryogenic coating system. After sublimation to -90°C for approximately 5 minutes in the Leica EM ACE200 cryogenic coating system to remove ice from the surface of the fresh continental shale sample slices, a 5 nm thick layer of tungsten was electroplated onto the fresh continental shale sample slices to enhance their conductivity, resulting in pretreated fresh continental shale sample slices.

[0117] Pretreated fresh continental shale sample slices were transferred to the sample chamber of a cryo-focused ion beam scanning electron microscope under frozen conditions. Multiple two-dimensional fresh surfaces were etched on the first region of interest on the pretreated fresh continental shale sample slices using a focused ion beam at a first temperature.

[0118] Optionally, in this embodiment of the present disclosure, the first temperature can be in the range of -130°C to -170°C.

[0119] Preferably, in this embodiment of the present disclosure, the first temperature can be -150°C.

[0120] Scanning electron microscope images of fresh surfaces were acquired using cryo-focused ion beam scanning electron microscopy as two-dimensional imaging characterization results. Chemical composition data of fresh surfaces were acquired using an energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope as two-dimensional imaging characterization results.

[0121] The pretreated fresh terrestrial shale sample slices were heated to a second temperature. At the second temperature, scanning electron microscope images of the fresh surface were acquired again using a scanning electron microscope as two-dimensional imaging characterization results. The chemical composition data of the fresh surface were acquired again using the energy dispersive spectrometer on the scanning electron microscope as two-dimensional imaging characterization results.

[0122] Optionally, the first temperature in this embodiment is the same as the room temperature mentioned above, and the first temperature can be 25°C.

[0123] This embodiment utilizes multi-dimensional data, including lithology, lithofacies, total organic carbon content, and mineral assemblage of aged continental shale samples, to train a regional positioning model. Combined with lithological matching information from fresh continental shale samples, it determines the first regional positioning model corresponding to the fresh continental shale samples. This enables rapid and accurate identification of the first region of interest (ROI) on slices of fresh continental shale samples. High-resolution two-dimensional imaging of the RIO on the fresh continental shale sample slices is achieved using cryo-focused ion beam scanning electron microscopy, overcoming the problem of microstructural distortion caused by environmental interference in fresh continental shale samples. In characterizing fresh continental shale samples, not only is the original pore-fracture network and organic matter occurrence state of the shale completely preserved, but the influence of preservation conditions on microscopic features is also revealed through cross-sample data correlation. Ultimately, it achieves the characterization of at least one key dimension of fresh continental shale samples, providing microscopic data support that more closely approximates real underground conditions for shale oil reservoir evaluation, significantly improving the scientific rigor and reliability of exploration and development decisions.

[0124] As an optional embodiment, after acquiring the image of a slice of fresh continental shale sample, the method further includes: determining a second region of interest localization model corresponding to the fresh continental shale sample based on the feature data of the first dimension of the fresh continental shale sample. The second region of interest localization model corresponding to the fresh continental shale sample is obtained after training based on the feature data of the second dimension of the sample-arranged continental shale sample and the location information of the second region of interest on the slice of the sample-arranged continental shale sample.

[0125] It should be noted that after obtaining each primary-level terrestrial shale sample group and each secondary-level production terrestrial shale sample group, for each primary-level terrestrial shale sample group, the second dimension feature data of the terrestrial shale samples in the primary-level terrestrial shale sample group can be used as training samples, and the location information of the second region of interest on the terrestrial shale sample slices in the primary-level terrestrial shale sample group can be used as sample labels to train the second initial model, thereby obtaining the second region of interest localization model corresponding to the primary-level terrestrial shale sample group.

[0126] For each secondary set of continental shale samples, the second dimension feature data of each continental shale sample in the secondary set of continental shale samples can be used as training samples, and the location information of the second region of interest on the continental shale sample slice of each continental shale sample in the secondary set of continental shale samples can be used as sample labels to train the second initial model, thereby obtaining the second region of interest localization model corresponding to the secondary set of continental shale samples.

[0127] It should be noted that the second initial model in this embodiment can be constructed based on supervised learning algorithms, such as support vector machine (SVM), random forest (RF) and artificial neural network (ANN). The human initial model in this embodiment can also be constructed based on deep learning algorithms, such as convolutional neural network (CNN) or generative adversarial network (GANs).

[0128] After determining the aged continental shale sample set corresponding to the fresh continental shale sample, the location model of the second region of interest corresponding to the aged continental shale sample set corresponding to the fresh continental shale sample can be determined as the location model of the second region of interest corresponding to the fresh continental shale sample set.

[0129] The image of a slice of fresh continental shale sample is input into the localization model of the second region of interest corresponding to the fresh continental shale sample, and the location information of the second region of interest on the slice of fresh continental shale sample is obtained from the localization model of the second region of interest corresponding to the fresh continental shale sample.

[0130] Specifically, after determining the location model of the second region of interest (ROI) corresponding to the fresh continental shale sample, the image of the fresh continental shale sample slice can be input into the location model of the ROI corresponding to the fresh continental shale sample. The location model of the ROI corresponding to the fresh continental shale sample can extract key features such as porosity, pore morphology, mineral distribution, micro-fracture characteristics, and spatial structure characteristics from the image of the fresh continental shale sample slice. Based on the above key features in the image of the fresh continental shale sample slice, the ROI can be determined in the image of the fresh continental shale sample slice. Furthermore, based on the mapping relationship between the image of the fresh continental shale sample slice and the fresh continental shale sample slice, the location information of the ROI on the fresh continental shale sample slice can be obtained and output.

[0131] Based on the location information of the second region of interest on the slice of fresh continental shale sample, the second region of interest on the slice of fresh continental shale sample is characterized by three-dimensional imaging using cryo-focused ion beam scanning electron microscopy. Then, based on the three-dimensional imaging characterization results, the third-dimensional feature data of the fresh continental shale sample is obtained.

[0132] Specifically, after obtaining the location information of the second region of interest on the fresh continental shale sample slice output by the first region localization model corresponding to the fresh continental shale sample, three-dimensional imaging characterization can be performed in the second region of interest of the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy. One or more three-dimensional imaging characterization results can be obtained. Then, based on the above three-dimensional imaging characterization results, the third-dimensional feature data of the fresh continental shale sample can be obtained through numerical calculation, mathematical statistics, image processing, feature fusion and deep learning techniques.

[0133] As an optional embodiment, based on the location information of the second region of interest on the fresh continental shale sample slice, the second region of interest on the fresh continental shale sample slice is characterized by three-dimensional imaging using cryo-focused ion beam scanning electron microscopy imaging technology. This includes: using a focused ion beam to etch a cube of a target size into the second region of interest on the pretreated fresh continental shale sample slice at a first temperature.

[0134] It should be noted that the target size in the embodiments of this disclosure can be determined based on prior knowledge and / or actual conditions. The target size can be 9μm × 6μm × 10μm.

[0135] Figure 2 is a scanning electron microscope image of a cube etched into a pre-treated fresh continental shale sample slice in the continental shale oil characterization method provided in this disclosure. The cube of the target size is shown in Figure 2.

[0136] At a first temperature, a cube is sliced ​​to a preset thickness using a focused ion beam. Scanning electron microscopy images of each cube slice are obtained using a cryo-focused ion beam scanning electron microscope. The chemical composition data of each cube slice is obtained using an energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope. The number of cube slices is a preset number.

[0137] Specifically, the cube is sliced ​​at a preset thickness at a first temperature, and for each cube slice obtained, a scanning electron microscope image of the cube slice is acquired using a cryo-focused ion beam scanning electron microscope, and the chemical composition data of the cube slice is acquired using an energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope.

[0138] It should be noted that the preset thickness in this embodiment can be determined based on prior knowledge and / or actual conditions. For example, the value range of the preset thickness can be from 5μm to 9μm. This embodiment does not limit the specific value of the preset thickness.

[0139] Optionally, the preset thickness can be 7 μm.

[0140] The slicing process ends when the number of cubic slices obtained from the slicing reaches a preset number. The preset number can range from 600 to 800.

[0141] Optionally, the above-mentioned preset quantity can be 700.

[0142] It is understandable that the size of the cube slices mentioned above is 9μm×6μm.

[0143] Three-dimensional skeleton modeling is performed based on scanning electron microscope images of each cubic slice to obtain a three-dimensional skeleton model of the cube. Based on the chemical composition data of each cubic slice, a pore space structure is generated in the three-dimensional skeleton model of the cube to obtain a three-dimensional model of the cube, which serves as the result of three-dimensional imaging characterization.

[0144] Specifically, by importing the scanning electron microscope images of each cubic slice into Avizo software and performing three-dimensional skeleton structure modeling, the three-dimensional skeleton model of the aforementioned cube can be obtained.

[0145] Based on the differences in imaging grayscale and the chemical composition data of each cube slice, threshold segmentation technology is used to distinguish and render the inorganic minerals, solid organic matter, liquid hydrocarbons and various types of pore space structures developed in situ in the 3D skeleton model of the above cubes. The 3D model of the above cubes can be obtained as the 3D imaging characterization result.

[0146] This embodiment utilizes multi-dimensional data, including lithology, lithofacies, total organic carbon content, and mineral assemblage of aged continental shale samples, to train a regional positioning model. Combined with lithological matching information from fresh continental shale samples, it determines the second region of interest (ROI) positioning model corresponding to the fresh continental shale samples. This enables rapid and accurate identification of the ROI on slices of fresh continental shale samples. Cryo-focused ion beam scanning electron microscopy is used to perform three-dimensional tomographic imaging of the ROI on slices of fresh continental shale samples. This overcomes the limitations of two-dimensional imaging in terms of pore connectivity and fracture spatial distribution, preserving the original three-dimensional structural data of the fresh continental shale samples. It better reveals the three-dimensional characteristics of nanopore distribution, fracture extension patterns, and organic matter occurrence morphology in fresh continental shale samples. Ultimately, it achieves the characteristic characterization of at least one key dimension of fresh continental shale samples, providing microscopic data support closer to real underground conditions for shale oil reservoir evaluation, significantly improving the scientific rigor and reliability of exploration and development decisions.

[0147] Figure 3 is a schematic diagram of the structure of the continental shale oil characterization device provided in this disclosure. The continental shale oil characterization device provided in this disclosure will be described below with reference to Figure 3. The continental shale oil characterization device described below can be referred to in correspondence with the continental shale oil characterization method described above. As shown in Figure 3, the device includes: a data acquisition module 301 and a characterization module 302.

[0148] The data acquisition module 301 is used to acquire the first and second dimension feature data of aged continental shale samples and the first dimension feature data of fresh continental shale samples. Aged continental shale samples are obtained in the target underground area using pressure-holding coring technology and are stored in a normal temperature and pressure environment for more than a first preset time after acquisition. Fresh continental shale samples are obtained in the target underground area using pressure-holding coring technology and are stored in a low-temperature environment for no more than a second preset time after acquisition. Fresh continental shale samples are isolated from air during storage in the low-temperature environment. The first dimension includes at least one of lithology type, lithofacies type, and maturity. The second dimension includes at least one of total organic carbon content and / or mineral assemblage.

[0149] The feature characterization module 302 is used to characterize the fresh continental shale sample based on the feature data of the first and second dimensions of the aged continental shale sample and the feature data of the first dimension of the fresh continental shale sample using cryo-focused ion beam scanning electron microscopy imaging technology, and to obtain the feature data of the third dimension of the fresh continental shale sample; the third dimension includes at least one of occurrence characteristics, main controlling factors and effective oil storage space.

[0150] Specifically, the data acquisition module 301 and the feature characterization module 302 are electrically connected.

[0151] The continental shale oil characterization device in this embodiment preserves fresh continental shale samples obtained using pressure-holding coring technology in a low-temperature, air-isolated environment before characterization. This maximizes the preservation of the physical and chemical properties of the fresh continental shale samples, keeping them as close as possible to their original state, thus improving the accuracy of subsequent characterization. It can utilize the first and second dimension characteristic data of aged continental shale samples preserved at room temperature for a long time to provide data guidance for characterizing fresh continental shale samples. Furthermore, it can utilize the high-resolution three-dimensional imaging technology of cryo-focused ion beam scanning electron microscopy to achieve in-situ imaging characterization of fresh continental shale samples. This allows for more accurate acquisition of at least one dimension of characteristic data in terms of the occurrence characteristics, main controlling factors, and effective oil storage space of fresh continental shale. It effectively overcomes the data distortion bottleneck caused by sample degradation in traditional characterization methods, providing a more accurate data foundation for shale oil exploration, development, and production, and has significant guiding significance for the formulation of shale oil exploration and development plans.

[0152] Figure 4 illustrates a schematic diagram of the physical structure of an electronic device. As shown in Figure 4, the electronic device may include: a processor 410, a communication interface 420, a memory 430, and a communication bus 440. The processor 410, communication interface 420, and memory 430 communicate with each other via the communication bus 440. The processor 410 can call logical instructions in the memory 430 to execute a method for characterizing continental shale oil features. This method includes: acquiring feature data of the first and second dimensions of aged continental shale samples; acquiring feature data of the first dimension of fresh continental shale samples; the aged continental shale samples are obtained in the target underground area using pressure-holding coring technology and then stored in a normal temperature and pressure environment for more than a first preset time; the fresh continental shale samples are obtained in the target underground area using pressure-holding coring technology and then stored in a low-temperature environment for no more than a second preset time. The facies shale samples, specifically fresh continental shale samples preserved in a low-temperature environment and isolated from air; the first dimension includes at least one of lithology type, lithofacies type, and maturity; the second dimension includes at least one of total organic carbon content and / or mineral assemblage; based on the characteristic data of the first and second dimensions of the aged continental shale samples and the characteristic data of the first dimension of the fresh continental shale samples, cryo-focused ion beam scanning electron microscopy imaging technology is used to characterize the fresh continental shale samples and obtain the characteristic data of the third dimension of the fresh continental shale samples; the third dimension includes at least one of occurrence characteristics, main controlling factors, and effective oil-bearing space.

[0153] Furthermore, the logical instructions in the aforementioned memory 430 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this disclosure, 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. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this disclosure. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0154] On the other hand, this disclosure also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the continental shale oil characteristic characterization method provided by the above methods. This method includes: acquiring characteristic data of the first and second dimensions of aged continental shale samples, and acquiring characteristic data of the first dimension of fresh continental shale samples; the aged continental shale samples are obtained in the target underground area using pressure-holding coring technology, and are then stored in a normal temperature and pressure environment for more than a first preset time after acquisition; the fresh continental shale samples are obtained in the target underground area using pressure-holding coring technology. The fresh continental shale samples are obtained from storage and stored in a low-temperature environment for no more than a second preset time after acquisition. The fresh continental shale samples are isolated from air during storage in the low-temperature environment. The first dimension includes at least one of lithology type, lithofacies type, and maturity. The second dimension includes at least one of total organic carbon content and / or mineral assemblage. Based on the characteristic data of the first and second dimensions of the stored continental shale samples and the characteristic data of the first dimension of the fresh continental shale samples, the fresh continental shale samples are characterized using cryo-focused ion beam scanning electron microscopy imaging technology to obtain the characteristic data of the third dimension of the fresh continental shale samples. The third dimension includes at least one of occurrence characteristics, main controlling factors, and effective oil storage space.

[0155] Furthermore, this disclosure also provides a non-transitory computer-readable storage medium storing a computer program thereon. When executed by a processor, the computer program is implemented to perform the continental shale oil characteristic characterization method provided by the above methods. This method includes: acquiring characteristic data of a first dimension and a second dimension of an aged continental shale sample; acquiring characteristic data of a first dimension of a fresh continental shale sample; the aged continental shale sample is obtained in a target subsurface area using pressure-holding coring technology, and after acquisition, the continental shale sample is placed in a normal temperature and pressure environment and stored for more than a first preset time; the fresh continental shale sample is obtained in a target subsurface area using pressure-holding coring technology, and after acquisition, the fresh continental shale sample is placed in a normal temperature and pressure environment and stored for more than a first preset time. Continental shale samples are preserved in a low-temperature environment for no more than a second preset time, and fresh continental shale samples are isolated from air during low-temperature preservation; the first dimension includes at least one of lithology type, lithofacies type, and maturity; the second dimension includes at least one of total organic carbon content and / or mineral assemblage; based on the characteristic data of the first and second dimensions of the aged continental shale samples and the characteristic data of the first dimension of the fresh continental shale samples, the fresh continental shale samples are characterized using cryo-focused ion beam scanning electron microscopy imaging technology to obtain the characteristic data of the third dimension of the fresh continental shale samples; the third dimension includes at least one of occurrence characteristics, main controlling factors, and effective oil storage space.

[0156] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0157] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0158] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A method for characterizing continental shale oil features, comprising: Obtain the first and second dimension feature data of aged continental shale samples, and obtain the first dimension feature data of fresh continental shale samples. The aged continental shale samples were obtained from the target underground area using pressure-controlled coring technology and then stored in a normal temperature and pressure environment for more than a first preset time. The fresh continental shale samples were obtained from the target underground area using pressure-controlled coring technology and then stored in a low-temperature environment for no more than a second preset time. The fresh continental shale samples were isolated from air during storage in the low-temperature environment. The first dimension includes at least one of lithology type, lithofacies type, and maturity. The second dimension includes at least one of total organic carbon content and / or mineral assemblage. The low-temperature environment is a dry ice environment. Based on the first and second dimension feature data of the aged continental shale sample and the first dimension feature data of the fresh continental shale sample, the fresh continental shale sample is characterized using cryo-focused ion beam scanning electron microscopy imaging technology to obtain the third dimension feature data of the fresh continental shale sample; the third dimension includes at least one of occurrence characteristics, main controlling factors, and effective oil storage space.

2. The method for characterizing continental shale oil according to claim 1, wherein, Based on the feature data of the first and second dimensions of the aged continental shale sample and the feature data of the first dimension of the fresh continental shale sample, cryo-focused ion beam scanning electron microscopy imaging technology is used to characterize the fresh continental shale sample and obtain the feature data of the third dimension of the fresh continental shale sample, including: A portion of the fresh continental shale sample was sliced ​​to obtain a slice of the fresh continental shale sample, and an image of the slice of the fresh continental shale sample was obtained. Based on the first dimension feature data of the fresh continental shale sample, a first region localization model corresponding to the fresh continental shale sample is determined. The first region localization model corresponding to the fresh continental shale sample is obtained after training based on the second dimension feature data of the sample-stored continental shale sample and the location information of the first region of interest on the slice of the sample-stored continental shale sample. The first dimension feature data of the sample-stored continental shale sample is matched with the first dimension feature data of the fresh continental shale sample. The stored continental shale sample includes the sample-stored continental shale sample. The slice of the sample-stored continental shale sample is obtained by slicing a portion of the sample-stored continental shale sample. The image of the fresh continental shale sample slice is input into the first region localization model corresponding to the fresh continental shale sample to obtain the location information of the first region of interest on the fresh continental shale sample slice output by the first region localization model corresponding to the fresh continental shale sample. Based on the location information of the first region of interest on the fresh continental shale sample slice, two-dimensional imaging characterization is performed on the first region of interest on the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy, and then the feature data of the third dimension of the fresh continental shale sample is obtained based on the two-dimensional imaging characterization results.

3. The method for characterizing continental shale oil according to claim 2, wherein, After acquiring the image of the fresh continental shale sample slice, the method further includes: Based on the feature data of the first dimension of the fresh continental shale sample, a second region of interest localization model corresponding to the fresh continental shale sample is determined. The second region of interest localization model corresponding to the fresh continental shale sample is obtained after training based on the feature data of the second dimension of the sample-arranged continental shale sample and the location information of the second region of interest on the slice of the sample-arranged continental shale sample. The image of the fresh continental shale sample slice is input into the second region of interest localization model corresponding to the fresh continental shale sample to obtain the location information of the second region of interest on the fresh continental shale sample slice output by the second region of interest localization model corresponding to the fresh continental shale sample. Based on the location information of the second region of interest on the fresh continental shale sample slice, the second region of interest on the fresh continental shale sample slice is characterized by three-dimensional imaging using cryo-focused ion beam scanning electron microscopy imaging technology. Then, based on the three-dimensional imaging characterization results, the feature data of the third dimension of the fresh continental shale sample are obtained.

4. The method for characterizing continental shale oil according to claim 3, wherein, The step of performing two-dimensional imaging characterization of the first region of interest on the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy based on the location information of the first region of interest on the fresh continental shale sample slice includes: The fresh continental shale sample slices were pretreated to obtain pretreated fresh continental shale sample slices. In a frozen state, the pretreated fresh terrestrial shale sample slice is transferred into the sample chamber of a cryo-focused ion beam scanning electron microscope, and multiple two-dimensional fresh surfaces are etched on the first region of interest on the pretreated fresh terrestrial shale sample slice using a focused ion beam at a first temperature. The scanning electron microscope image of the fresh surface is obtained using the cryo-focused ion beam scanning electron microscope as the two-dimensional imaging characterization result. The chemical composition data of the fresh surface is obtained using the energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope as the two-dimensional imaging characterization result. The pretreated fresh terrestrial shale sample slices are heated to a second temperature. At the second temperature, a scanning electron microscope image of the fresh surface is acquired again using a scanning electron microscope as the two-dimensional imaging characterization result. The chemical composition data of the fresh surface is acquired again using the energy dispersive spectrometer mounted on the scanning electron microscope as the two-dimensional imaging characterization result.

5. The method for characterizing continental shale oil according to claim 4, wherein, Based on the location information of the second region of interest on the fresh continental shale sample slice, the second region of interest on the fresh continental shale sample slice is characterized in three dimensions using cryo-focused ion beam scanning electron microscopy, including: At the first temperature, a cube of the target size is obtained by etching the second region of interest on the pretreated fresh terrestrial shale sample slice using a focused ion beam; At the first temperature, the cube is sliced ​​with a preset thickness using a focused ion beam. The scanning electron microscope image of each cube slice is obtained using the cryo-focused ion beam scanning electron microscope. The chemical composition data of each cube slice is obtained using the energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope. The number of each cube slice is a preset number. Three-dimensional skeleton modeling is performed based on the scanning electron microscope images of each cubic slice to obtain a three-dimensional skeleton model of the cube. Based on the chemical composition data of each cubic slice, a pore space structure is generated in the three-dimensional skeleton model of the cube to obtain a three-dimensional model of the cube, which serves as the three-dimensional imaging characterization result.

6. The method for characterizing continental shale oil according to any one of claims 1 to 5, wherein, The fresh terrestrial shale sample was obtained through the following steps: after obtaining the terrestrial shale sample from the target underground area using pressure-holding coring technology, a protective layer was applied to the surface of the terrestrial shale sample to isolate it from air. After the protective layer is applied to the surface of the continental shale sample, the continental shale sample with the protective layer is stored in dry ice. If the preservation time of the continental shale sample covered with the protective layer in dry ice does not exceed the second preset time, the continental shale sample is identified as the fresh continental shale sample.

7. A device for characterizing continental shale oil features, comprising: The data acquisition module is used to acquire feature data of the first and second dimensions of aged continental shale samples, and to acquire feature data of the first dimension of fresh continental shale samples. The aged continental shale samples are obtained in the target underground area using pressure-holding coring technology and are then stored in a normal temperature and pressure environment for more than a first preset time. The fresh continental shale samples are obtained in the target underground area using pressure-holding coring technology and are then stored in a low-temperature environment for no more than a second preset time, wherein the fresh continental shale samples are isolated from air during storage in the low-temperature environment. The first dimension includes at least one of lithology type, lithofacies type, and maturity. The second dimension includes at least one of total organic carbon content and / or mineral assemblage. The low-temperature environment is a dry ice environment. The feature characterization module is used to characterize the fresh continental shale sample based on the feature data of the first and second dimensions of the aged continental shale sample and the feature data of the first dimension of the fresh continental shale sample using cryo-focused ion beam scanning electron microscopy imaging technology, and to obtain the feature data of the third dimension of the fresh continental shale sample; the third dimension includes at least one of occurrence characteristics, main controlling factors and effective oil storage space.

8. The continental shale oil characterization device according to claim 7, wherein, in, Based on the feature data of the first and second dimensions of the aged continental shale sample and the feature data of the first dimension of the fresh continental shale sample, cryo-focused ion beam scanning electron microscopy imaging technology is used to characterize the fresh continental shale sample and obtain the feature data of the third dimension of the fresh continental shale sample, including: A portion of the fresh continental shale sample was sliced ​​to obtain a slice of the fresh continental shale sample, and an image of the slice of the fresh continental shale sample was obtained. Based on the first dimension feature data of the fresh continental shale sample, a first region localization model corresponding to the fresh continental shale sample is determined. The first region localization model corresponding to the fresh continental shale sample is obtained after training based on the second dimension feature data of the sample-stored continental shale sample and the location information of the first region of interest on the slice of the sample-stored continental shale sample. The first dimension feature data of the sample-stored continental shale sample is matched with the first dimension feature data of the fresh continental shale sample. The stored continental shale sample includes the sample-stored continental shale sample. The slice of the sample-stored continental shale sample is obtained by slicing a portion of the sample-stored continental shale sample. The image of the fresh continental shale sample slice is input into the first region localization model corresponding to the fresh continental shale sample to obtain the location information of the first region of interest on the fresh continental shale sample slice output by the first region localization model corresponding to the fresh continental shale sample. Based on the location information of the first region of interest on the fresh continental shale sample slice, two-dimensional imaging characterization is performed on the first region of interest on the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy, and then the feature data of the third dimension of the fresh continental shale sample is obtained based on the two-dimensional imaging characterization results.

9. The method for characterizing continental shale oil according to claim 8, wherein, After acquiring the image of the fresh continental shale sample slice, the method further includes: Based on the feature data of the first dimension of the fresh continental shale sample, a second region of interest localization model corresponding to the fresh continental shale sample is determined. The second region of interest localization model corresponding to the fresh continental shale sample is obtained after training based on the feature data of the second dimension of the sample-arranged continental shale sample and the location information of the second region of interest on the slice of the sample-arranged continental shale sample. The image of the fresh continental shale sample slice is input into the second region of interest localization model corresponding to the fresh continental shale sample to obtain the location information of the second region of interest on the fresh continental shale sample slice output by the second region of interest localization model corresponding to the fresh continental shale sample. Based on the location information of the second region of interest on the fresh continental shale sample slice, the second region of interest on the fresh continental shale sample slice is characterized by three-dimensional imaging using cryo-focused ion beam scanning electron microscopy imaging technology. Then, based on the three-dimensional imaging characterization results, the feature data of the third dimension of the fresh continental shale sample are obtained.

10. The method for characterizing continental shale oil according to claim 9, wherein, The step of performing two-dimensional imaging characterization of the first region of interest on the fresh continental shale sample slice using cryo-focused ion beam scanning electron microscopy based on the location information of the first region of interest on the fresh continental shale sample slice includes: The fresh continental shale sample slices were pretreated to obtain pretreated fresh continental shale sample slices. In a frozen state, the pretreated fresh terrestrial shale sample slice is transferred into the sample chamber of a cryo-focused ion beam scanning electron microscope, and multiple two-dimensional fresh surfaces are etched on the first region of interest on the pretreated fresh terrestrial shale sample slice using a focused ion beam at a first temperature. The scanning electron microscope image of the fresh surface is obtained using the cryo-focused ion beam scanning electron microscope as the two-dimensional imaging characterization result. The chemical composition data of the fresh surface is obtained using the energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope as the two-dimensional imaging characterization result. The pretreated fresh terrestrial shale sample slices are heated to a second temperature. At the second temperature, a scanning electron microscope image of the fresh surface is acquired again using a scanning electron microscope as the two-dimensional imaging characterization result. The chemical composition data of the fresh surface is acquired again using the energy dispersive spectrometer mounted on the scanning electron microscope as the two-dimensional imaging characterization result.

11. The method for characterizing continental shale oil according to claim 10, wherein, Based on the location information of the second region of interest on the fresh continental shale sample slice, the second region of interest on the fresh continental shale sample slice is characterized in three dimensions using cryo-focused ion beam scanning electron microscopy, including: At the first temperature, a cube of the target size is obtained by etching the second region of interest on the pretreated fresh terrestrial shale sample slice using a focused ion beam; At the first temperature, the cube is sliced ​​with a preset thickness using a focused ion beam. The scanning electron microscope image of each cube slice is obtained using the cryo-focused ion beam scanning electron microscope. The chemical composition data of each cube slice is obtained using the energy dispersive spectrometer mounted on the cryo-focused ion beam scanning electron microscope. The number of each cube slice is a preset number. Three-dimensional skeleton modeling is performed based on the scanning electron microscope images of each cubic slice to obtain a three-dimensional skeleton model of the cube. Based on the chemical composition data of each cubic slice, a pore space structure is generated in the three-dimensional skeleton model of the cube to obtain a three-dimensional model of the cube, which serves as the three-dimensional imaging characterization result.

12. The method for characterizing continental shale oil according to any one of claims 7 to 11, wherein, The fresh terrestrial shale sample was obtained through the following steps: after obtaining the terrestrial shale sample from the target underground area using pressure-holding coring technology, a protective layer was applied to the surface of the terrestrial shale sample to isolate it from air. After the protective layer is applied to the surface of the continental shale sample, the continental shale sample with the protective layer is stored in dry ice. If the preservation time of the continental shale sample covered with the protective layer in dry ice does not exceed the second preset time, the continental shale sample is identified as the fresh continental shale sample.

13. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the method for characterizing continental shale oil as described in any one of claims 1 to 6.

14. A non-transitory computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the method for characterizing continental shale oil as described in any one of claims 1 to 6.

Images