A method, device and electronic device for determining the direction of paleo-stress in a formation

Abstract

The present disclosure provides a method, apparatus and electronic device for determining the paleo-stress direction of a formation. The method includes: obtaining a shale sample and an imaging logging image of the shale sample, where the bedding plane of the shale sample is clear and conjugate shear fractures are developed, the conjugate shear fractures intersect the bedding plane, and the conjugate shear fractures are filled with authigenic minerals; restoring the true orientation of the shale sample according to the imaging logging image; determining the original occurrence of the conjugate shear fractures according to the true orientation of the shale sample; determining the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures; and determining the paleo-stress direction of the shale sample in a specific geological historical period according to the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures. Applying this method has strong operability, relatively accurate results, and is more conducive to popularization and application in the fields of structural geology and petroleum geology.

Description

Technical Field

[0001] The present disclosure relates to the field of geological research, and in particular, to a method, apparatus, and electronic device for determining the paleo-stress direction of a formation. Background Art

[0002] The determination of the paleo-stress direction is a prerequisite for understanding the nature of tectonic activities in the geological history period, analyzing the strike of faults and the tectonic deformation mechanism, and is an important means for reconstructing the regional tectonic evolution history. Existing paleo-stress direction analysis methods include: analyzing based on field outcrop profiles through the strike of faults and joints and the fold direction; or analyzing based on indoor microfabric characteristics such as rock acoustic emission, paleomagnetism, physical simulation, and numerical simulation. However, for hydrocarbon-bearing basin reservoirs lacking field outcrops such as deep sea and deep formations, the drilling cores often lack the original azimuth information, and the existing paleo-stress direction analysis methods have limitations. Summary of the Invention

[0003] The present disclosure provides a method, apparatus, electronic device, and storage medium for determining the paleo-stress direction of a formation to at least solve the above technical problems existing in the prior art.

[0004] According to a first aspect of the present disclosure, there is provided a method for determining the paleo-stress direction of a formation, the method including: obtaining a shale sample and an imaging logging image of the shale sample, the shale sample having clear bedding planes and developed conjugate shear fractures, the conjugate shear fractures intersecting the bedding planes, and the conjugate shear fractures filled with authigenic minerals; restoring the true azimuth of the shale sample according to the imaging logging image; determining the original occurrence of the conjugate shear fractures according to the true azimuth of the shale sample; determining the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures; and determining the paleo-stress direction of the shale sample in a specific geological history period according to the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures; wherein, the determining the original occurrence of the conjugate shear fractures according to the true azimuth of the shale sample includes: projecting the poles corresponding to the bedding planes of the shale sample and the poles corresponding to the conjugate shear fracture planes onto a stereographic projection diagram, and a Wulff net diagram is placed below the stereographic projection diagram; rotating the Wulff net diagram clockwise with the strike of the bedding plane as the rotation axis, and the rotation angle is the same as the angle corresponding to the strike of the bedding plane; moving the pole corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection diagram, and restoring the position of the pole corresponding to the original occurrence of the conjugate shear fractures on the stereographic projection diagram to obtain the original occurrence of the conjugate shear fractures.

[0005] In one feasible embodiment, restoring the true orientation of the shale sample according to the imaging logging image includes: placing the shale sample according to preset requirements, rotating the shale sample to match the characteristics of the bedding plane of the shale sample with the characteristics of the imaging logging image, and determining the true orientation of the shale sample underground.

[0006] In one feasible embodiment, determining the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures includes: determining the precipitation time of the authigenic minerals through mineral dating techniques; and determining the formation period of the conjugate shear fractures according to the precipitation time.

[0007] According to a second aspect of the present disclosure, there is provided a device for determining the paleo-stress direction of a formation. The device includes: an acquisition module for acquiring a shale sample and an imaging logging image of the shale sample, where the bedding plane of the shale sample is clear and conjugate shear fractures are developed, the conjugate shear fractures intersect with the bedding plane, and the conjugate shear fractures are filled with authigenic minerals; a restoration module for restoring the true orientation of the shale sample according to the imaging logging image; a first determination module for determining the original occurrence of the conjugate shear fractures according to the true orientation of the shale sample; a second determination module for determining the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures; and a third determination module for determining the paleo-stress direction of the shale sample in a specific geological historical period according to the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures. Among them, the first determination module is specifically configured to project the poles corresponding to the bedding plane of the shale sample and the poles corresponding to the conjugate shear fracture plane onto a stereographic projection diagram, and a Wulff net diagram is placed below the stereographic projection diagram; using the strike of the bedding plane as the rotation axis, rotating the Wulff net diagram clockwise by an angle consistent with the angle corresponding to the strike of the bedding plane; moving the pole corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection diagram, and restoring the position of the pole corresponding to the original occurrence of the conjugate shear fractures on the stereographic projection diagram to obtain the original occurrence of the conjugate shear fractures.

[0008] In one feasible embodiment, the restoration module is specifically configured to place the shale sample according to preset requirements, rotate the shale sample to match the characteristics of the bedding plane of the shale sample with the characteristics of the imaging logging image, and determine the true orientation of the shale sample underground.

[0009] In one feasible embodiment, the second determination module includes: a first determination sub-module for determining the precipitation time of the authigenic minerals through mineral dating techniques; and a second determination sub-module for determining the formation period of the conjugate shear fractures according to the precipitation time.

[0010] According to a third aspect of the present disclosure, there is provided an electronic device, including:

[0011] at least one processor; and

[0012] a memory communicatively connected to the at least one processor; wherein,

[0013] the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method described in the present disclosure.

[0014] According to a fourth aspect of the present disclosure, there is provided a non-transitory computer-readable storage medium storing computer instructions for causing a computer to execute the method described in the present disclosure.

[0015] A method, apparatus, electronic device and storage medium for determining the paleo-stress direction of a formation in the present disclosure first obtain a shale sample with clear bedding planes and developed conjugate shear fractures, and the conjugate shear fractures intersect the bedding planes. Autogenous minerals are filled in the conjugate shear fractures, and an imaging logging image corresponding to the shale sample is obtained. Based on the imaging logging image, the original occurrence of the conjugate shear fractures of the shale sample is determined. Paleo-stress information is recorded in the conjugate shear fractures. Therefore, by analyzing the original occurrence of the conjugate shear fractures, the paleo-stress direction of the shale sample can be determined. In addition, autogenous minerals are filled in the shale sample, and the autogenous minerals contain information such as the geological history period. By analyzing the autogenous minerals, the historical period corresponding to the shale sample can be determined. Applying this method can overcome the limitations of paleo-stress direction analysis caused by the lack of original orientation information in field geological outcrops and drilling cores. It is highly operable, the results are relatively accurate, and it is easier to be popularized and applied in the fields of structural geology and oil and gas geology.

[0016] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it used to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become easily understood. In the drawings, several embodiments of the present disclosure are shown in an exemplary and non-limiting manner, wherein:

[0018] In the drawings, the same or corresponding reference numerals represent the same or corresponding parts.

[0019] Figure 1The figure shows a schematic implementation flowchart of a method for determining the paleo-stress direction of a formation according to an embodiment of the present disclosure;

[0020] Figure 2 The figure shows a schematic process of determining the original occurrence of conjugate shear fractures according to an embodiment of the present disclosure Figure 1 ;

[0021] Figure 3 The figure shows a schematic process of determining the original occurrence of conjugate shear fractures according to an embodiment of the present disclosure Figure 2 ;

[0022] Figure 4 The figure shows a schematic process of determining the original occurrence of conjugate shear fractures according to an embodiment of the present disclosure Figure 3 ;

[0023] Figure 5 The figure shows a schematic process of determining the original occurrence of conjugate shear fractures according to an embodiment of the present disclosure Figure 4 ;

[0024] Figure 6 The figure shows a schematic of a shale sample before restoring the original occurrence of conjugate shear fractures according to an embodiment of the present disclosure Figure 1 ;

[0025] Figure 7 The figure shows a schematic of a shale sample before restoring the original occurrence of conjugate shear fractures according to an embodiment of the present disclosure Figure 2 ;

[0026] Figure 8 The figure shows a schematic diagram of the feature matching between the bedding plane of a shale sample and an image logging image according to an embodiment of the present disclosure;

[0027] Figure 9 The figure shows a schematic module diagram of a device for determining the paleo-stress direction of a formation according to an embodiment of the present disclosure;

[0028] Figure 10 The figure shows a schematic composition structure diagram of an electronic device according to an embodiment of the present disclosure. Detailed implementation manners

[0029] To make the objectives, features, and advantages of the present disclosure more obvious and understandable, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present disclosure.

[0030] Figure 1 The figure shows a schematic implementation flowchart of a method for determining the paleo-stress direction of a formation according to an embodiment of the present disclosure.

[0031] See Figure 1 Figure 1 , according to the first aspect of the embodiments of the present disclosure, a method for determining the paleo-stress direction of a formation is provided. The method includes: Step 101, obtaining a shale sample and an imaging logging image of the shale sample. The bedding plane of the shale sample is clear and conjugate shear fractures are developed. The conjugate shear fractures intersect with the bedding plane, and the conjugate shear fractures are filled with authigenic minerals; Step 102, restoring the true orientation of the shale sample according to the imaging logging image; Step 103, determining the original occurrence of the conjugate shear fractures according to the true orientation of the shale sample; Step 104, determining the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures; Step 105, determining the paleo-stress direction of the shale sample in a specific geological historical period according to the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures.

[0032] This application first obtains a shale sample, which is obtained by drilling. At the same time, an imaging logging image of the shale sample is obtained. The imaging logging image is obtained by a specific logging technology and is an image reflecting the distribution of physical parameters of the wellbore or objects around the well. The selected shale sample has a clear bedding plane and developed conjugate shear fractures. The bedding plane is caused by environmental changes or sedimentation changes during the sedimentation process; the conjugate shear fractures are fractures formed by the rock under stress, usually manifested as two sets of intersecting shear planes, and the development degrees of the two sets of fractures may be unbalanced. This application selects the more developed set of conjugate shear fractures, and the conjugate shear fractures in the selected shale sample intersect with the bedding plane. The conjugate shear fractures are filled with authigenic minerals, which can be calcite, dolomite, quartz, etc. The mineral type of the authigenic minerals is not specific.

[0033] During the drilling process, the orientation of the shale sample will change. Therefore, the collected shale sample is matched with its corresponding imaging logging image to restore the true orientation of the shale sample underground. After determining the true orientation of the shale sample underground, the original occurrence of the conjugate shear fractures on the shale sample can be determined. Since the conjugate shear fractures are fractures formed by the rock under stress, the stress direction on the shale sample can be determined according to the original occurrence of the conjugate shear fractures. The direction of the acute angle of the conjugate shear fractures in the original occurrence of the conjugate shear fractures is the stress direction on the shale sample. In addition, during the geological structure process, the shale sample forms conjugate shear fractures after being subjected to shear stress, and these fractures will be filled with authigenic minerals subsequently. Therefore, the formation period of the conjugate shear fractures can be determined according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures. Finally, the paleo-stress direction of the shale sample in a specific geological historical period is determined according to the paleo-stress direction determined by the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures.

[0034] Further, the original occurrence of conjugate shear fractures is determined according to the true orientation of the shale sample, including: projecting the poles corresponding to the bedding plane of the shale sample and the poles corresponding to the conjugate shear fracture plane onto a stereographic projection diagram, with a Wulff net diagram placed below the stereographic projection diagram; using the strike of the bedding plane as the rotation axis, rotating the Wulff net diagram clockwise, and the rotation angle is the same as the angle corresponding to the strike of the bedding plane; moving the pole corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection diagram, restoring the position of the pole corresponding to the original occurrence of the conjugate shear fracture on the stereographic projection diagram, and obtaining the original occurrence of the conjugate shear fracture.

[0035] As Figures 2 - 5 shown, Figure 2 Shown is the display of projecting the pole corresponding to the bedding plane, i.e., pole A, and the pole corresponding to the conjugate shear fracture plane, i.e., pole B, onto the stereographic projection diagram. A Wulff net diagram is placed below this stereographic projection diagram. Then, as Figure 3 shown, using the strike of the bedding plane as the rotation axis, rotating the Wulff net diagram clockwise, where the rotation angle is the same as the angle corresponding to the strike of the bedding plane, and rotating the bedding plane to the horizontal state. Finally, as Figure 4 and Figure 5 shown, moving the pole corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection diagram. When the pole corresponding to the bedding plane moves, the pole corresponding to the conjugate shear fracture plane also moves accordingly. When the pole of the bedding plane moves to the center of the stereographic projection diagram, determining the position of the pole corresponding to the conjugate shear fracture plane is the position of the pole corresponding to the original occurrence of the conjugate shear fracture on the stereographic projection diagram, i.e., Figure 5 pole in, and finally obtaining the original occurrence of the conjugate shear fracture.

[0036] Figure 6 Shows a schematic diagram of the shale sample before restoring the original occurrence of the conjugate shear fracture Figure 1 , Figure 7 Shows a schematic diagram of the shale sample after restoring the original occurrence of the conjugate shear fracture Figure 2 . As Figure 6 and Figure 7 shown, Fa and Fb are the conjugate shear fractures of the shale sample, The direction of the arrow is the paleo-stress direction of the shale sample determined based on the original occurrence of conjugate shear fractures. In this application, first, a shale sample and its corresponding imaging logging image are obtained. According to the imaging logging image, the true orientation of the shale sample in the ground can be restored to further determine the original occurrence of conjugate shear fractures on the shale sample. Based on the precipitation time of authigenic minerals filled in the conjugate shear fractures, the formation period of the conjugate shear fractures is determined. Finally, based on the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures, the paleo-stress direction of the shale sample in a specific geological historical period is determined. Applying this method can overcome the problem of limited paleo-stress direction analysis caused by the lack of original orientation information such as field geological outcrops and drilling cores, and has strong operability and relatively accurate results.

[0037] Figure 8 FIG. shows a schematic diagram of the feature matching between the bedding plane of the shale sample in the embodiment of the present disclosure and the imaging logging image.

[0038] As Figure 8 shown, according to the imaging logging image, restoring the true orientation of the shale sample includes: placing the shale sample according to preset requirements, rotating the shale sample to make the features of the bedding plane of the shale sample match the features of the imaging logging image, and determining the true orientation of the shale sample in the ground.

[0039] The shale sample is placed perpendicular to the horizontal plane at 90°, and then the shale sample is rotated to make the dip information and dip angle information of the bedding plane of the shale sample match the bedding plane information of the imaging logging image corresponding to the depth position of the shale sample. The position corresponding to the matching result is the true orientation of the shale sample in the ground. That is Figure 8 In, first place the shale sample perpendicular to the horizontal plane and rotate it so that after the bedding plane is unfolded, its dip information and dip angle information match the bedding plane information of the imaging logging image at the corresponding depth position.

[0040] In an implementable manner, determining the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures includes: determining the precipitation time of the authigenic minerals through mineral dating technology; determining the formation period of the conjugate shear fractures according to the precipitation time.

[0041] In this application, the precipitation time of authigenic minerals can be detected by mineral dating techniques, and this precipitation time is determined as the formation period of conjugate shear fractures. Among them, when the authigenic mineral is calcite or dolomite, the uranium-lead dating technique can be used to determine the precipitation time of calcite or dolomite. When the authigenic mineral is quartz, the rubidium-strontium dating technique can be used to determine the precipitation time of quartz. The uranium-lead dating technique and the rubidium-strontium dating technique have high precision, and the formation period of conjugate shear fractures determined by using the uranium-lead dating technique and the rubidium-strontium dating technique in this application is more accurate.

[0042] Figure 9 The module schematic diagram of a device for determining the paleo-stress direction of a formation according to an embodiment of the present disclosure is shown.

[0043] See Figure 9 , according to the second aspect of the present disclosure, a device for determining the paleo-stress direction of a formation is provided. The device includes: an acquisition module 901, configured to acquire a shale sample and an imaging logging image of the shale sample. The bedding plane of the shale sample is clear and conjugate shear fractures are developed. The conjugate shear fractures intersect with the bedding plane, and authigenic minerals are filled in the conjugate shear fractures; a restoration module 902, configured to restore the true orientation of the shale sample according to the imaging logging image; a first determination module 903, configured to determine the original occurrence of the conjugate shear fractures according to the true orientation of the shale sample; a second determination module 904, configured to determine the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures; a third determination module 905, configured to determine the paleo-stress direction of the shale sample in a specific geological historical period according to the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures. The first determination module is specifically configured to project the poles corresponding to the bedding plane of the shale sample and the poles corresponding to the conjugate shear fracture plane onto a stereographic projection chart, and a Wulff net chart is placed below the stereographic projection chart; using the strike of the bedding plane as the rotation axis, rotate the Wulff net chart clockwise, and the rotation angle is the same as the angle corresponding to the strike of the bedding plane; move the pole corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection chart, and restore the position of the pole corresponding to the original occurrence of the conjugate shear fractures on the stereographic projection chart to obtain the original occurrence of the conjugate shear fractures.

[0044] In an implementable manner, the restoration module 902 is specifically configured to place the shale sample according to a preset requirement, rotate the shale sample, so that the characteristics of the bedding plane of the shale sample match the characteristics of the imaging logging image, and determine the true orientation of the shale sample underground.

[0045] In an implementable embodiment, the second determination module 904 includes: a first determination sub-module 9041, configured to determine the precipitation time of authigenic minerals through a mineral dating technique; and a second determination sub-module 9042, configured to determine the formation period of conjugate shear fractures according to the precipitation time.

[0046] According to an embodiment of the present disclosure, the present disclosure further provides an electronic device and a readable storage medium.

[0047] Figure 10 FIG. shows a schematic block diagram of an exemplary electronic device 1000 that can be used to implement embodiments of the present disclosure. The electronic device is intended to represent various forms of digital computers, such as, for example, a laptop computer, a desktop computer, a workbench, a personal digital assistant, a server, a blade server, a mainframe computer, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as, for example, a personal digital processor, a cellular phone, a smart phone, a wearable device, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely exemplary and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0048] As Figure 10 shown, the device 1000 includes a computing unit 1001, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 1002 or a computer program loaded from a storage unit 1008 into a random access memory (RAM) 1003. In the RAM 1003, various programs and data required for the operation of the device 1000 can also be stored. The computing unit 1001, the ROM 1002, and the RAM 1003 are connected to each other through a bus 1004. An input / output (I / O) interface 1005 is also connected to the bus 1004.

[0049] A plurality of components in the device 1000 are connected to the I / O interface 1005, including: an input unit 1006, such as a keyboard, a mouse, etc.; an output unit 1007, such as various types of displays, speakers, etc.; a storage unit 1008, such as a magnetic disk, an optical disk, etc.; and a communication unit 1009, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 1009 allows the device 1000 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0050] The computing unit 1001 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 1001 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 1001 executes the various methods and processes described above, such as a method for determining the paleo-stress direction of a formation. For example, in some embodiments, a method for determining the paleo-stress direction of a formation can be implemented as a computer software program tangibly embodied in a machine-readable medium, such as the storage unit 1008. In some embodiments, part or all of the computer program can be loaded and / or installed onto the device 1000 via the ROM 1002 and / or the communication unit 1009. When the computer program is loaded into the RAM 1003 and executed by the computing unit 1001, one or more steps of the method for determining the paleo-stress direction of a formation described above can be executed. Alternatively, in other embodiments, the computing unit 1001 can be configured to execute a method for determining the paleo-stress direction of a formation by any other suitable means (e.g., by means of firmware).

[0051] The various embodiments of the systems and techniques described above in this document can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SOCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a dedicated or general-purpose programmable processor, receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting the data and instructions to the storage system, the at least one input device, and the at least one output device.

[0052] The program code for implementing the methods of the present disclosure can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the program code is executed by the processor or controller, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The program code can be executed entirely on the machine, partially on the machine, as an independent software package partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0053] In the context of this disclosure, a machine-readable medium can be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0054] To provide for interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the computer. Other kinds of devices can also be used to provide for interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic, speech, or tactile input).

[0055] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer having a graphical user interface or a web browser through which the user can interact with an implementation of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of a communication network include: a local area network (LAN), a wide area network (WAN), and the Internet.

[0056] A computer system may include a client and a server. The client and the server are generally far away from each other and usually interact via a communication network. The relationship between the client and the server is generated by computer programs running on the respective computers and having a client-server relationship with each other. The server may be a cloud server, a server of a distributed system, or a server incorporating a blockchain.

[0057] It should be understood that various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and no limitation is imposed herein.

[0058] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this disclosure, "a plurality of" means two or more, unless otherwise specifically defined.

[0059] As described above, this is only the specific implementation manner of this disclosure, but the protection scope of this disclosure is not limited thereto. Any person skilled in the art within the technical scope disclosed in this disclosure can easily think of changes or substitutions, which should all be covered within the protection scope of this disclosure. Therefore, the protection scope of this disclosure should be subject to the protection scope of the claimed rights.

Claims

1. A method for determining the direction of paleo - stress in strata, characterized in that, The method includes: Obtaining a shale sample and an imaging logging image of the shale sample, where the bedding plane of the shale sample is clear and conjugate shear fractures are developed, the conjugate shear fractures intersect with the bedding plane, and the conjugate shear fractures are filled with authigenic minerals; Restoring the true orientation of the shale sample according to the imaging logging image; Determining the original occurrence of the conjugate shear fractures according to the true orientation of the shale sample; Determining the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures; Determining the paleo-stress direction of the shale sample in a specific geological historical period according to the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures; Among them, restoring the true orientation of the shale sample according to the imaging logging image includes: placing the shale sample according to preset requirements, rotating the shale sample to match the characteristics of the bedding plane of the shale sample with the characteristics of the imaging logging image, and determining the true orientation of the shale sample underground; Determining the original occurrence of the conjugate shear fractures according to the true orientation of the shale sample includes: projecting the poles corresponding to the bedding plane of the shale sample and the poles corresponding to the conjugate shear fracture planes onto a stereographic projection diagram, and a Wulff net diagram is placed below the stereographic projection diagram; using the strike of the bedding plane as the rotation axis, rotating the Wulff net diagram clockwise, and the rotation angle is the same as the angle corresponding to the strike of the bedding plane; moving the poles corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection diagram, restoring the position of the poles corresponding to the original occurrence of the conjugate shear fractures on the stereographic projection diagram, and obtaining the original occurrence of the conjugate shear fractures; The specific process is as follows: Project the poles corresponding to the bedding plane, i.e., pole A, and the poles corresponding to the conjugate shear fracture planes, i.e., pole B, onto the stereographic projection diagram for display. A Wulff net diagram is placed below the stereographic projection diagram. Using the strike of the bedding plane as the rotation axis, rotate the Wulff net diagram clockwise, where the rotation angle is the same as the angle corresponding to the strike of the bedding plane, rotate the bedding plane to the horizontal state, move the poles corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection diagram. When the poles corresponding to the bedding plane move, the poles corresponding to the conjugate shear fracture planes also move accordingly. When the poles corresponding to the bedding plane move to the center of the stereographic projection diagram, determine the position of the poles corresponding to the conjugate shear fracture planes as the position of the poles corresponding to the original occurrence of the conjugate shear fractures on the stereographic projection diagram, i.e., the required pole B', and finally obtain the original occurrence of the conjugate shear fractures; Determining the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures includes: determining the precipitation time of the authigenic minerals through mineral dating technology; determining the formation period of the conjugate shear fractures according to the precipitation time.

2. A device for determining the direction of paleo - stress in a formation, characterized in that, The device includes: An acquisition module for acquiring a shale sample and an imaging logging image of the shale sample, where the bedding plane of the shale sample is clear and conjugate shear fractures are developed, the conjugate shear fractures intersect with the bedding plane, and the conjugate shear fractures are filled with authigenic minerals; A restoration module, configured to restore the true orientation of the shale sample according to the imaging logging image; A first determination module, configured to determine the original occurrence of the conjugate shear fractures according to the true orientation of the shale sample; A second determination module, configured to determine the formation period of the conjugate shear fractures according to the precipitation time of the authigenic minerals filled in the conjugate shear fractures; A third determination module, configured to determine the paleo-stress direction of the shale sample in a specific geological history period according to the original occurrence of the conjugate shear fractures and the formation period of the conjugate shear fractures; Wherein, the restoration module is specifically configured to place the shale sample according to preset requirements, rotate the shale sample to match the characteristics of the bedding plane of the shale sample with the characteristics of the imaging logging image, and determine the true orientation of the shale sample underground; The first determination module is specifically configured to project the poles corresponding to the bedding plane of the shale sample and the poles corresponding to the conjugate shear fracture plane onto a stereographic projection diagram, and a Wulff net diagram is placed below the stereographic projection diagram; taking the strike of the bedding plane as the rotation axis, rotate the Wulff net diagram clockwise, and the rotation angle is consistent with the angle corresponding to the strike of the bedding plane; move the pole corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection diagram, and restore the position of the pole corresponding to the original occurrence of the conjugate shear fractures on the stereographic projection diagram to obtain the original occurrence of the conjugate shear fractures; The specific process is as follows: Project the pole corresponding to the bedding plane, i.e., pole A, and the pole corresponding to the conjugate shear fracture plane, i.e., pole B, onto the stereographic projection diagram for display. A Wulff net diagram is placed below the stereographic projection diagram. Taking the strike of the bedding plane as the rotation axis, rotate the Wulff net diagram clockwise, where the rotation angle is consistent with the angle corresponding to the strike of the bedding plane, rotate the bedding plane to the horizontal state, and move the pole corresponding to the bedding plane along the latitude direction to the center point of the stereographic projection diagram. When the pole corresponding to the bedding plane moves, the pole corresponding to the conjugate shear fracture plane also moves accordingly. When the pole of the bedding plane moves to the center of the stereographic projection diagram, determine the position of the pole corresponding to the conjugate shear fracture plane as the position of the pole corresponding to the original occurrence of the conjugate shear fractures on the stereographic projection diagram, i.e., the required pole B', and finally obtain the original occurrence of the conjugate shear fractures; The second determination module includes: a first determination sub-module, configured to determine the precipitation time of the authigenic minerals through mineral dating technology; a second determination sub-module, configured to determine the formation period of the conjugate shear fractures according to the precipitation time.

3. An electronic device, characterized in that, Including: At least one processor; And a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method described in claim 1.

4. A non-transitory computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to cause a computer to execute the method described in claim 1.

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