Method and system for searching oil-rich reservoir in continental facies shale oil reservoir based on rock paleomagnetic characteristics

Abstract

The invention belongs to the technical field of shale oil exploration, and discloses a method for searching for an oil-rich reservoir in a continental facies shale oil reservoir based on rock paleomagnetic characteristics. Therefore, the paleomagnetic characteristics of the shale sample are used as connection points of volcanic activities and organic matter enrichment, and rapid and accurate positioning of the organic matter-rich horizon in the shale is guided. Rock powder is not needed in the magnetic susceptibility test, only about 10 g of rock fragments are needed, about 30 samples can be tested in one hour, the machine-hour cost is 3000 yuan / hour, and each sample is about 100 yuan. Therefore, a large amount of time and test cost can be saved after the method is used. The method is favorable for testing a large number of samples, and is applied to early exploration of organic matter-rich horizon selection.

Description

Technical Field

[0001] The present invention belongs to the technical field of shale oil exploration, and in particular relates to a method and system for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics. Background Art

[0002] Lacustrine shale refers to a type of rock with foliated structure formed in a lake environment during the geological period and composed of fine-grained sediments (including terrigenous debris and authigenic carbonate minerals) with a particle size of less than 62.5 μm. Shale oil refers to the oil resources contained in shale formations.

[0003] Shale oil resources rich in lacustrine shale formations have been developed in many oil and gas basins in different periods in my country, and have shown characteristics such as wide distribution, large total thickness, high organic matter content and rich brittle minerals, which meet the international evaluation standards for high-quality shale oil. However, due to the strong heterogeneity of lithology and oil and gas distribution of continental sedimentary rocks, this type of shale oil shows the characteristics of rapid production decline, low recovery rate and poor development efficiency in the process of applying North American shale oil exploration and development technology methods. It is worth noting that volcanic-hydrothermal activity sediments have been developed in many sets of shale oil layers developed in the extensional geological background in my country, and they have a clear coupling relationship with the enrichment of organic matter. Therefore, a shale oil exploration method based on the characteristics of shale oil in my country can be established.

[0004] At present, the main method for determining the organic matter-rich layer in shale oil is the total organic carbon content (TOC) test. This indicator directly reveals the degree of organic matter enrichment in the shale layer and is the most important parameter in the early exploration and evaluation of shale oil. However, this experiment requires the shale sample to be tested to be ground into powder before testing it using a carbon-sulfur analyzer or a rock pyrolyzer, which has the disadvantages of a relatively long test cycle and high cost.

[0005] Through the above analysis, the problems and defects of the prior art are as follows: Continental shale oil layers are highly heterogeneous in both lithology and oil content distribution, requiring accurate and rapid oil layer division and positioning. In addition, the current method for determining the organic matter-rich layer in shale oil mainly uses the total organic carbon content (TOC) test. This indicator directly reveals the degree of organic matter enrichment in the shale layer and is the most important parameter in the early exploration and evaluation of shale oil. However, this experiment requires the shale sample to be tested to be ground into powder first, and then tested using a carbon-sulfur analyzer or a rock pyrolyzer, which has the disadvantages of a relatively long test cycle and high cost. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides a method for finding oil-rich strata in continental shale oil layers based on the paleomagnetic characteristics of rocks.

[0007] The present invention is implemented in this way: a method for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics comprises: Step 1: Collect and investigate geological background information; The geological background data mainly include the regional tectonic background and sedimentary evolution characteristics; if the shale under study is an oil and gas basin formed in a tensional tectonic background, it is applicable to the present invention; Step 2: partial sample collection, processing, and paleomagnetic and total organic carbon testing; Step 3: Microscopic identification of rock and mineral characteristics; Step 4: test data analysis; Step five: Conduct large-scale and detailed testing to establish paleomagnetic profiles and accurately locate the organic-rich strata of shale oil.

[0008] Further, some of the samples were collected, processed, and tested for paleomagnetic and total organic carbon: A section of shale oil layer drilling core with a length of about 1 m was selected for detailed observation, collection and testing, which specifically included the following steps: ① Observe the core and divide the rock into small layers according to the lithology changes visible to the naked eye; ② First, cut a 2 cm long, 1 cm wide and 2 cm thick core slice; then divide the sample into two along the vertical direction, one for making electron probe rock slices; the other half is evenly divided into two, one is ground into 200 mesh rock powder, and the other is tested for magnetic susceptibility; ③ Use a carbon-sulfur analyzer to test the total organic carbon content of a portion of the powder; keep the remaining powder for later use; ④ Establish the longitudinal numerical correlation curve between magnetic susceptibility and TOC.

[0009] Further, the microscopic identification of rock and mineral characteristics: ① Make electron probe slices for inflection point samples and observe the main mineral crystal morphology characteristics, such as chicken bone-shaped volcanic glass, angular quartz and feldspar with stepped ends; ② The remaining powder of the inflection point sample in step 2 is tested for its mineral composition by X-ray diffraction, mainly to observe whether the clay is mainly composed of montmorillonite; ③ If the above observations are visible, the inflection point is considered to be affected by volcanic activity.

[0010] Further, the test data analysis: ① The production institute observed the TOC and magnetic susceptibility value change curves in the vertical direction of the core section to see whether the two have the same change trend and preliminarily determine whether the linear relationship is established; ② If it is established, continue to use the results of step 4 to exclude some data points, that is, points that do not contain volcanic materials but show abnormally high magnetic susceptibility; ③ Perform correlation numerical analysis on all correlation values, determine the correlation parameters between the two and observe whether there is a threshold; ④ Use the effective TOC value and correlation relationship to determine the effective magnetic susceptibility range.

[0011] Another object of the present invention is to provide a system for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics, comprising: The data collection module is used to collect and investigate geological background data; the geological background data mainly includes regional tectonic background and sedimentary evolution characteristics; if the shale under study is an oil and gas basin formed in a tensional tectonic background, the present invention is applicable; The test module is used for partial sample collection, processing, and paleomagnetism and total organic carbon testing; Identification module, used for microscopic identification of rock and mineral characteristics; Analysis module, used for test data analysis; The positioning module is used for large-scale detailed testing, establishing paleomagnetic profiles, and accurately locating organic-rich strata in shale oil.

[0012] Another object of the present invention is to provide a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method for finding oil-rich strata in continental shale oil layers based on the paleomagnetic characteristics of rocks.

[0013] Another object of the present invention is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to execute the steps of the method for finding oil-rich strata in continental shale oil layers based on the paleomagnetic characteristics of rocks.

[0014] Another object of the present invention is to provide an information data processing terminal, which is used to implement the system for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics.

[0015] First, the current determination of organic-rich layers in shale layers mainly relies on the total organic carbon content (TOC) test, which has the disadvantages of being time-consuming and expensive. For example, the most commonly used method is to use a carbon-sulfur analyzer or a rock pyrolysis instrument for testing, which requires the rock sample to be ground into powder before being tested on the machine. The cost of each sample is about 350 yuan, and about 12 samples can be tested in one hour.

[0016] Since the magnetic susceptibility test does not require rock powder, only about 10 g of rock fragments are needed, about 30 samples can be tested in 1 hour, the machine hour fee is 3,000 yuan / hour, and each sample is about 100 yuan. Therefore, the method of the present invention can save a lot of time and testing costs. It is conducive to the testing of a large number of samples and is applied to the selection of organic-rich layers in the early stage of exploration.

[0017] Second, as auxiliary evidence of the inventiveness of the claims of the present invention, it is also reflected in the following important aspects: The expected benefits and commercial value of the technical solution of the present invention after transformation are: The present invention changes the traditional use of shale whole rock organic carbon content (TOC) as a key evaluation index for finding high-quality shale oil layers to the use of shale magnetic susceptibility as an evaluation index. The establishment of this method can effectively reduce time and economic costs. For example: taking the test of 1 m shale core as an example, taking 2 cm as the standard for testing one sample, a total of 50 samples need to be tested. If the traditional TOC test method is used, it will cost about 17,500 yuan (350 yuan / piece*50), the sample will be crushed for about 12.5 hours (about 15 minutes per sample), and the TOC test will take about 4.2 hours (about 5 minutes per sample). If this scheme is used, it will cost 5,000 yuan (100 yuan per piece) and 1.6 hours (about 2 minutes per piece). Although this scheme requires an investment of about 6,000 yuan in the early stage of rock and mineral verification (taking 10 samples to be tested as an example, 3,000 yuan for electron probe sample preparation and observation and 3,000 yuan for X-ray diffraction), this verification process is not required when a large number of samples are tested in the later stage. Therefore, this solution greatly saves economic and time costs, and will accumulate cost savings in the subsequent large-scale sample testing process, and has obvious commercial value.

[0018] (2) Whether the technical solution of the present invention solves the technical problems that people have been eager to solve but have never been able to solve successfully: The relationship between volcanic activity and organic matter enrichment in shale layers has become a consensus in the field of scientific research, but the problem of how to transform this scientific discovery into oil and gas production has never been solved. In addition, today's oil and gas exploration and development mainly rely on well logging and seismic methods based on geophysics, which is significantly different from scientific research based on geochemistry, petrology and mineralogy. The core of the present invention is to use the geomagnetic method in geophysics as a bridge to connect scientific discoveries with production practice, thereby solving the problem of long-term decoupling of production, learning and research in this field. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flow chart of a method for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics provided by an embodiment of the present invention.

[0020] Figure 2 It is a detailed flow chart of a method for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics provided by an embodiment of the present invention.

[0021] Figure 3 It is a structural block diagram of a system for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics provided by an embodiment of the present invention.

[0022] Figure 4 The sample core, microphotograph and corresponding magnetic susceptibility and total organic carbon (TOC) change curves provided in the embodiments of the present invention. A & B. Laminated tuffaceous dolomite. The volcanic debris is mainly chicken bone-shaped and angular glass fragments (white particles in A), which are completely extinct under an orthogonal microscope (black particles in B). C & D. Cloud-bearing tuff. The debris is mainly chicken bone-shaped glass fragments (white particles in C, completely extinct in D) and angular felsic fragments (first-level gray-white interference color particles in D). E & F. Shale containing felsic fragments (white particles). G & H. Micritic dolomite. No obvious felsic fragments are found. I. The shale is mainly composed of mud-grade particles, containing a small amount of silt-grade feldspar and quartz particles and a small amount of organic debris (black). J. The felsic mud-silt-grade particles in the shale are mostly angular. The pores are rich in organic matter (black) and pyrite (white). A, C, E, G are single polarized microphotographs, B, D, F, H are corresponding orthogonal polarized microphotographs, and I and J are electron probe backscattered microphotographs. K. Photograph of a drilling core containing obvious volcanic debris and its magnetic susceptibility and TOC variation curve characteristics. Lenticular tuffaceous dolomite (yellow-brown) and dolomite tuff (gray-green with obvious clastic structure) are mostly interbedded with syn-sedimentary soft deformation, with a small amount of shale layers (dark gray-black laminae) in some places. The red box is the sampling location of the magnetic susceptibility and TOC test samples. L. Photograph of a drilling core without obvious volcanic debris and its magnetic susceptibility and TOC variation curve characteristics. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] like Figure 1 , 2 As shown, a method for finding oil-rich layers in continental shale oil layers based on rock paleomagnetic characteristics provided by an embodiment of the present invention includes the following steps: S101, collect and investigate geological background data; The geological background data mainly include the regional tectonic background and sedimentary evolution characteristics; if the shale under study is an oil and gas basin formed in a tensional tectonic background, it is applicable to the present invention; S102, partial sample collection, processing, and paleomagnetic and total organic carbon testing; S103, microscopic identification of rock and mineral characteristics; S104, test data analysis; S105, large-scale and detailed testing, establishment of paleomagnetic profile, precise location of shale oil organic-rich strata.

[0025] The present invention provides a method for finding oil-rich layers in continental shale oil layers based on the paleomagnetic characteristics of rocks. By analyzing the paleomagnetic characteristics and organic matter content, the organic-rich layers of shale oil can be accurately located. The specific working principle is as follows: First, in step S101, the geological background data of the region is collected and investigated. This step determines whether the exploration of shale oil layers in the target area is suitable for the present invention by analyzing the tectonic background and sedimentary evolution characteristics of the target area. If the shale in the study area is formed in an oil and gas basin with a tensional tectonic background, it means that the shale oil enrichment in the region may be affected by volcanic activity, which is suitable for further paleomagnetic analysis and then used to find favorable strata.

[0026] Next, enter step S102, i.e. sample collection, processing, paleomagnetic and total organic carbon (TOC) testing. This process requires the collection of shale samples in the target area, especially samples obtained at different levels, to ensure that the samples are representative. The collected samples need to be pre-treated to remove impurities and stabilize the properties of the samples. Subsequently, the paleomagnetic characteristics and TOC content of the samples are measured by professional equipment. Paleomagnetic data can reflect the characteristics of the geomagnetic field during the sedimentation period of the strata, thereby indicating the strength of volcanic activity, and TOC content is one of the important signs of shale oil enrichment.

[0027] In step S103, microscopic identification of rock and mineral characteristics is performed. Through rock and mineral analysis, different mineral components and structural characteristics in shale samples with abnormal paleomagnetic characteristics (high or low values) are identified, and whether the genesis and sedimentary environment of the shale are related to volcanic activity is evaluated at a microscopic level.

[0028] Step S104 performs a detailed analysis of the aforementioned test data. The paleomagnetic data is combined with the variation trend of the TOC content to determine the manifestation of the distribution law of the organic-rich strata in the shale in the paleomagnetic data. The paleomagnetic characteristics are observed to change with the strata, as well as the fluctuation characteristics of the TOC content in different strata, to form a preliminary correspondence between the paleomagnetic profile and the characteristics of the organic strata.

[0029] In step S105, based on the preliminary analysis results, a large-scale detailed test is conducted to establish a paleomagnetic profile, and then the paleomagnetic characteristics are used to find organic-rich layers in shale. This step further improves the positioning accuracy of shale oil-rich layers by increasing the sampling density and measurement frequency, refining the profile information, and further improving the positioning accuracy of shale oil-rich layers. Detailed testing can also enhance the applicability of the model and make it applicable to a wider range of regions.

[0030] Finally, by establishing a paleomagnetic profile, the organic-rich layers of shale oil were accurately located. Based on the aforementioned geological background, microscopic identification, paleomagnetic data and TOC analysis results, the location of the shale oil-rich layers was finally determined.

[0031] Part of the sample collection, processing, paleomagnetism and total organic carbon testing provided by the embodiments of the present invention: This step can randomly select a shale oil layer drilling core of about 1 m in length for detailed observation, collection and testing, which specifically includes the following steps: ① Observe the core and divide the rock into small layers according to the visible lithology changes (color, composition, bedding); ② First, cut a core piece of 2 cm long, 1 cm wide (when the thickness of the small layer is less than 1 cm, the layer thickness shall prevail) and 2 cm thick; then divide the sample into two parts along the vertical direction, one part is used to make the electron probe rock slice; the other part is evenly divided into two parts, one part is ground into 200 mesh rock powder, and the other part is used to test the magnetic susceptibility; ③ Use a carbon-sulfur analyzer to test the total organic carbon content (TOC) of a portion of the powder; keep the remaining powder for later use; ④ Establish the longitudinal numerical correlation curve between magnetic susceptibility and TOC.

[0032] Microscopic identification of rock and mineral characteristics provided by the embodiments of the present invention: This step mainly conducts mineral ultra-microscopic morphological observation and X-ray diffraction mineral composition test on samples with abnormal inflection points (maximum and minimum) in the magnetic susceptibility curve, and jointly constrains and bidirectionally verifies the strength information of volcanic activity reflected by the magnetic susceptibility characteristics from a mineralogical perspective; it specifically includes the following steps: ① For the inflection point samples, electron probe slices (2 cm long, 1 cm wide, 60 μm thick) were prepared to observe the main mineral crystal morphology characteristics, such as chicken bone-shaped volcanic glass ( Figure 4 AJ), angular quartz and feldspar with stepped ends; ② The remaining powder of the inflection point sample in step 2 is tested for its mineral composition by X-ray diffraction, mainly to observe whether the clay is mainly composed of montmorillonite; ③ If the above observations are visible, the turning point is considered to be affected by volcanic activity ( Figure 4 K, L).

[0033] Test data analysis provided by the embodiment of the present invention: Correlation and threshold summarization, construction of standard favorable value range This step is mainly to establish a numerical correlation between the magnetic susceptibility value and the TOC value; specifically, it includes the following steps: ① The production institute observed the TOC and magnetic susceptibility value change curves in the vertical direction of the core section to see whether the two have the same change trend and preliminarily determine whether the linear relationship is established; ② If it is established, continue to use the results of step 4 to exclude some data points, that is, points that do not contain volcanic materials but show abnormally high magnetic susceptibility; ③ Perform correlation numerical analysis on all correlation values, determine the correlation parameters between the two and observe whether there is a threshold; ④ Use the effective TOC value and correlation relationship to determine the effective magnetic susceptibility range.

[0034] like Figure 3 As shown, a system for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics provided by an embodiment of the present invention includes: The data collection module is used to collect and investigate geological background data; the geological background data mainly includes regional tectonic background and sedimentary evolution characteristics; if the shale under study is an oil and gas basin formed in a tensional tectonic background, the present invention is applicable; The test module is used for partial sample collection, processing, and paleomagnetism and total organic carbon testing; Identification module, used for microscopic identification of rock and mineral characteristics; Analysis module, used for test data analysis; The positioning module is used for large-scale detailed testing, establishing paleomagnetic profiles, and accurately locating organic-rich strata in shale oil.

[0035] Another object of the present invention is to provide a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method for finding oil-rich strata in continental shale oil layers based on the paleomagnetic characteristics of rocks.

[0036] Another object of the present invention is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to execute the steps of the method for finding oil-rich strata in continental shale oil layers based on the paleomagnetic characteristics of rocks.

[0037] Another object of the present invention is to provide an information data processing terminal, which is used to implement the system for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics.

[0038] The system for finding oil-rich layers in continental shale oil layers based on rock paleomagnetic characteristics of the present invention realizes efficient and accurate positioning and identification of shale oil-rich layers through the collaborative work of multiple modules. The following is the detailed working principle of the system: First, the data collection module is used to collect and investigate the geological background data of the target area. The work content of this module mainly includes the analysis of the regional tectonic background and the study of sedimentary evolution characteristics. By understanding the regional tectonic background, especially if the shale is formed in the oil and gas basin with a tensional tectonic background, the applicability of the present invention can be further judged. The geological background data provides directional guidance for subsequent sampling and analysis, and lays the foundation for the accurate identification of oil-rich strata.

[0039] Next, the test module conducts detailed testing and analysis on the collected samples. First, some target rock samples are collected on-site and sent to the laboratory for processing. The sample processing process includes cleaning, cutting and preparation into standard test pieces suitable for testing. Subsequently, the test module conducts paleomagnetic tests and total organic carbon (TOC) content tests on the samples. Paleomagnetic tests can reveal the geomagnetic characteristics of the shale formation period, while TOC tests directly reflect the organic matter content in the samples, thereby preliminarily evaluating the oil potential of the samples. This process provides key data on geomagnetic characteristics and organic matter enrichment, providing a basis for the subsequent precise positioning of oil-rich strata.

[0040] The identification module further conducts microscopic identification of the rock and mineral characteristics of the collected samples. Through microscope and electron microscope observation, the identification module can analyze the mineral composition, structural characteristics, porosity and other microscopic properties of the rock. These microscopic characteristics are crucial for determining the sedimentary environment and organic matter enrichment of the shale. The work of the identification module ensures the accuracy of the test samples and provides more detailed mineral and lithological characteristics for subsequent data analysis and stratigraphic positioning.

[0041] The analysis module is responsible for comprehensive analysis of the data obtained from testing and identification. In this module, the system combines paleomagnetic test results, TOC content and microscopic rock and mineral characteristics to conduct multi-dimensional data mining and feature association. Through these analyses, the system can identify geomagnetic features and organic matter enrichment patterns associated with high oil content. The analysis module uses data association analysis and statistical methods to identify key parameters and indicators that may be related to oil-rich strata, and further lock in potential high oil-bearing strata areas.

[0042] The positioning module conducts detailed tests on a large scale based on the analysis results to establish a systematic paleomagnetic profile. The module conducts densely distributed detailed sampling and testing in the target area, and draws the paleomagnetic profile of each sampling point to accurately locate the organic-rich strata of shale oil. Through the positioning module, the system can effectively lock the oil-rich strata in a large area to a specific geological section, significantly improving the pertinence and accuracy of subsequent mining.

[0043] The present invention also provides a computer device, which includes a memory and a processor. The memory stores a computer program, and when the processor executes the program, the above-mentioned oil-rich stratum analysis and positioning method steps can be automatically executed. This device automatically realizes data collection, processing, analysis and result output, greatly reduces the workload of manual operation, and improves analysis accuracy and processing efficiency.

[0044] In addition, the present invention also proposes a computer-readable storage medium, which stores an executable computer program. When the program is loaded and executed by a processor, each step of finding an oil-rich layer based on the paleomagnetic characteristics of rocks can be automatically completed. The storage medium is applicable to a variety of devices, such as a personal computer, a data analysis workstation, etc., thereby expanding the scope of application of the present invention.

[0045] Finally, the system also includes an information data processing terminal, which is used to integrate and process the acquired and analyzed geological and lithological data, and realize the full process automation from data collection, analysis to result output. The information data processing terminal can update and present the data analysis results in real time, which is convenient for researchers to dynamically monitor and deeply analyze the oil-bearing strata in different geological regions. This data terminal provides geologists with intelligent data support and visual analysis interface, and provides convenience and scientific basis for the identification and precise positioning of oil-rich strata.

[0046] The present invention is specifically implemented: Step 1: Collect and investigate geological background information Collect regional tectonic background information, including geological maps, seismic data, previous research results, etc.

[0047] Investigate sedimentary evolution characteristics and analyze the sedimentary environment and history of the basin.

[0048] Determine whether the shale under study was formed in a petroliferous basin in a tensional tectonic setting.

[0049] Step 2: Partial sample collection, processing, and paleomagnetic and total organic carbon testing A section of shale oil layer drilling core with a length of about 1 meter was randomly selected.

[0050] Observe the core, record the changes in lithology, and divide it into small layers.

[0051] Cut a 2 cm x 1 cm x 2 cm core slice and divide it into two parts. One part is used to make electron probe rock slices; half of the other part is used to test magnetic susceptibility, and the other half is ground into 200 mesh rock powder.

[0052] The powder was tested for total organic carbon content (TOC) using a carbon-sulfur analyzer.

[0053] Establish the longitudinal value correlation curve between magnetic susceptibility and TOC ( Figure 4 K, L).

[0054] Step 3: Microscopic identification of rock and mineral characteristics Electron probe slices were made for samples with abnormal inflection points in the magnetic susceptibility curve to observe the mineral crystal morphology characteristics.

[0055] The mineralogical composition of the remaining powder was analyzed by X-ray diffraction, with particular attention paid to the types of clay minerals.

[0056] Based on the observation results, determine whether the turning point is affected by volcanic activity.

[0057] Step 4: Test data analysis Produce a curve of TOC and magnetic susceptibility values ​​along the longitudinal direction of the core section.

[0058] Analyze the curve, determine the linear relationship, and exclude abnormal data points.

[0059] Perform correlation numerical analysis and determine correlation parameters and thresholds.

[0060] The effective TOC value and correlation relationship are used to determine the effective magnetic susceptibility range.

[0061] Step 5: Conduct large-scale and detailed tests to establish paleomagnetic profiles and accurately locate organic-rich strata in shale oil Establish a paleomagnetic profile, combine it with geological background data, and use the effective magnetic susceptibility range determined in steps 2-4 to accurately locate the oil and gas rich strata.

[0062] Oil layer identification and positioning: Using the prediction model based on the paleomagnetic characteristics of rocks, the oil-rich layers in the continental shale oil layer can be accurately identified, which can improve the success rate of exploration and reduce the exploration cost. By analyzing the paleomagnetic data of rocks, combined with the geological structure and sedimentary environment information, it is possible to quickly and accurately locate the oil layer with high oil content and great mining potential, providing a scientific basis for subsequent drilling and development.

[0063] Oil and gas resource assessment: The prediction model based on rock paleomagnetic characteristics can also be used to assess oil and gas resources. Through comprehensive analysis of multiple oil-rich strata, the reserves and mining potential of the entire shale reservoir can be estimated, providing an important reference for oil companies' investment decisions.

[0064] Oil and gas exploration software development: This technical solution can be integrated into oil and gas exploration software to provide oil layer identification tools based on rock paleomagnetic characteristics. Through the software interface, users can input multi-source data such as geology, geophysics and geochemistry, and the software automatically analyzes and predicts oil-rich strata, assisting explorers in making more accurate decisions.

[0065] Oil and gas exploration consulting services: Based on this technical solution, oil and gas exploration consulting services can be carried out. Professional oil and gas exploration consulting and technical support can be provided to oil companies, geological survey institutions, etc., including services such as oil-rich stratum identification, drilling strategy optimization, and oil and gas resource assessment, to promote scientific and technological progress and industrial upgrading in the field of oil and gas exploration and development.

[0066] In summary, finding oil-rich strata in continental shale oil layers based on the paleomagnetic characteristics of rocks has broad application prospects and important economic value, and can provide strong technical support for the field of oil exploration and development.

[0067] The present invention is based on the scientific discovery that there is a coupling relationship between organic matter enrichment in shale and volcanic sediments. It uses paleomagnetic susceptibility to identify volcanic sediments in shale, and then finds organic-rich strata in shale. Based on the following three characteristics, magnetic susceptibility can be used to preliminarily identify volcanic information in shale: ① A large amount of dust-like magnetite will be produced during volcanic activity and transported to remote sedimentary areas along with volcanic ash; ② With the improvement of the performance of modern paleomagnetic research equipment, extremely small amounts of magnetite information can be captured in various sedimentary rocks, and magnetic susceptibility signals can be generated; ③ The single source and stability characteristics of magnetite are widely used in paleomagnetism to identify volcanic activity. In order to verify the effectiveness of the present invention, the correlation analysis of the magnetic susceptibility, rock mineralogy and TOC characteristics of 13 standard core samples (total thickness of 30 cm) has been completed ( Figure 4 The coupling relationship between the two indicates that the magnetic susceptibility can accurately reflect the presence of volcanic activity in shale and the relative intensity of volcanic activity, and has a significant correlation with TOC characteristics, that is, the magnetic susceptibility is between 3 and 5x10 -8 m 3 / kg, the TOC value often increases.

[0068] It should be noted that the embodiments of the present invention can be implemented by hardware, software, or a combination of software and hardware. The hardware part can be implemented using dedicated logic; the software part can be stored in a memory and executed by an appropriate instruction execution system, such as a microprocessor or a dedicated design software. A person of ordinary skill in the art will understand that the above-mentioned devices and methods can be implemented using computer executable instructions and / or contained in a processor control code, such as a carrier medium such as a disk, CD or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. Such code is provided on a carrier medium such as a disk, CD or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The device and its modules of the present invention can be implemented by hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., can also be implemented by software executed by various types of processors, and can also be implemented by a combination of the above-mentioned hardware circuits and software, such as firmware.

[0069] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modification, equivalent substitution and improvement made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics, characterized in that: The method for finding the oil-rich layer in the continental shale oil layer based on the paleomagnetic characteristics of rocks comprises the following steps: Step 1: Collect and investigate geological background information; The geological background data mainly include the regional tectonic background and sedimentary evolution characteristics; if the shale under study is an oil and gas basin formed in a tensional tectonic background, it is applicable to the present invention; Step 2: partial sample collection, processing, and paleomagnetic and total organic carbon testing; Step 3: Microscopic identification of rock and mineral characteristics; Step 4: test data analysis; Step five: Conduct large-scale and detailed testing to establish paleomagnetic profiles and accurately locate the organic-rich strata of shale oil.

2. The method for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics as claimed in claim 1, characterized in that: Some of the samples collected, processed, and tested for paleomagnetic and total organic carbon: A section of shale oil layer drilling core with a length of about 1 m was selected for detailed observation, collection and testing, which specifically included the following steps: ① Observe the core and divide the rock into small layers according to the lithology changes visible to the naked eye; ② First, cut a 2 cm long, 1 cm wide and 2 cm thick core slice; then divide the sample into two along the vertical direction, one for making electron probe rock slices; the other half is evenly divided into two, one is ground into 200 mesh rock powder, and the other is tested for magnetic susceptibility; ③ Use a carbon-sulfur analyzer to test the total organic carbon content of a portion of the powder; keep the remaining powder for later use; ④ Establish the longitudinal numerical correlation curve between magnetic susceptibility and TOC.

3. The method for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics as claimed in claim 1, characterized in that: Microscopic identification of rock and mineral characteristics: ① Make electron probe slices for inflection point samples and observe the main mineral crystal morphology characteristics, such as chicken bone-shaped volcanic glass, angular quartz and feldspar with stepped ends; ② The remaining powder of the inflection point sample in step 2 is tested for its mineral composition by X-ray diffraction, mainly to observe whether the clay is mainly composed of montmorillonite; ③ If the above observations are visible, the inflection point is considered to be affected by volcanic activity.

4. The method for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics as claimed in claim 1, characterized in that: The test data analysis: ① The production institute observed the TOC and magnetic susceptibility value change curves in the vertical direction of the core section to see whether the two have the same change trend and preliminarily determine whether the linear relationship is established; ② If it is established, continue to use the results of step 4 to exclude some data points, that is, points that do not contain volcanic materials but show abnormally high magnetic susceptibility; ③ Perform correlation numerical analysis on all correlation values, determine the correlation parameters between the two and observe whether there is a threshold; ④ Use the effective TOC value and correlation relationship to determine the effective magnetic susceptibility range.

5. A system for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics, which implements the method for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics as described in any one of claims 1 to 4, characterized in that: The method for finding the oil-rich stratum system in the continental shale oil layer based on the paleomagnetic characteristics of rocks includes: The data collection module is used to collect and investigate geological background data; the geological background data mainly includes regional tectonic background and sedimentary evolution characteristics; if the shale under study is an oil and gas basin formed in a tensional tectonic background, the present invention is applicable; The test module is used for partial sample collection, processing, and paleomagnetism and total organic carbon testing; Identification module, used for microscopic identification of rock and mineral characteristics; Analysis module, used for test data analysis; The positioning module is used for large-scale detailed testing, establishing paleomagnetic profiles, and accurately locating organic-rich strata in shale oil.

6. A computer device, characterized in that: The computer device includes a memory and a processor, the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method for finding oil-rich layers in continental shale oil layers based on rock paleomagnetic characteristics as described in any one of claims 1 to 4.

7. A computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to perform the steps of a method for finding oil-rich strata in continental shale oil layers based on paleomagnetic characteristics of rocks as described in any one of claims 1 to 4.

8. An information data processing terminal, characterized in that: The information data processing terminal is used to implement a system for finding oil-rich strata in continental shale oil layers based on rock paleomagnetic characteristics as described in claim 5.

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