Method for identifying coverage type recoil structure formed by impact of ancient planet on earth

Abstract

The invention belongs to the field of geophysics and geology, and discloses a method for identifying a coverage type recoil structure formed by an ancient planet impacting the earth, which comprises the following steps of: 1, explaining by using underground three-dimensional seismic data to obtain a geological structure morphological graph; a second step of identifying a negative annular structure associated with radioactive disruption in the occurrence age of planet impact high frequency in the geological structure form map; 3, recognizing an extrusion thrust fault on the periphery of the negative annular structure; and 4, recognizing the backlash anticline on the extrusion backlash fault hanging wall to obtain a coverage type backlash structure formed by the ancient planet impacting the earth. According to the method, the coverage type backlash structure of the ancient planet impact cause is comprehensively identified in the planet impact high-frequency occurrence time ancient structure map, the processing speed can be increased, the identification accuracy is improved, and the problem that the coverage type backlash structure is difficult to identify due to geological movement interference is solved.

Description

Technical Field

[0001] The present invention belongs to the field of geophysics and geology. More specifically, the present invention relates to a method for identifying a cover-type thrust structure formed by an ancient planet impacting the earth. Background Art

[0002] Ancient planetary impact structures have characteristic impact stratigraphic records, geochemical anomalies produced by impact, and mineral shock metamorphism. Traditional views focus on the impact of mantle uplift and plate collision. In recent years, new research evidence shows that ancient planetary impacts on the Earth will produce geological mineralization effects, and ancient planetary impacts on the Earth may play a key role in the formation of thrust structures. This kind of thrust structure has guiding significance for the search for oil and gas reservoirs.

[0003] In the prior art, most of the ancient planetary impact structures discovered are developed on the surface, which is easy to directly observe and measure. However, the ancient planetary impact structures developed in geological history have been disturbed by geological movements such as burial, diagenesis and structural deformation, making it difficult to identify based on current seismic data.

[0004] In view of this, there is an urgent need to provide a method to identify the covering thrust structures formed by the impact of ancient planets on the Earth, and to accurately identify the thrust structures caused by the impact of ancient planets. Summary of the invention

[0005] In order to at least solve the above-mentioned problems, the present invention provides a method for identifying cover-type thrust structures formed by ancient planetary impacts on the earth, comprising: a first step, using underground three-dimensional seismic data to interpret and obtain a geological structure morphology map; a second step, in the geological structure morphology map, in the high-frequency ages of planetary impacts, identifying negative annular structures accompanied by radioactive faults, wherein the high-frequency ages of planetary impacts include: the end of Ordovician, the end of Devonian, the end of Permian, the end of Triassic and the end of Cretaceous; a third step, identifying compressional thrust faults around the negative annular structure; a fourth step, identifying thrust anticlines on the upper plate of the compressional thrust faults, and obtaining cover-type thrust structures formed by the underground ancient planetary impact on the earth in the sedimentary cover area.

[0006] According to one embodiment of the present invention, in the first step, using underground three-dimensional seismic data to interpret a geological structure morphology map includes: restoring paleomorphic seismic geological data based on the underground three-dimensional seismic data to obtain a geological structure morphology map.

[0007] According to one embodiment of the present invention, in the second step, identifying a negative annular structure associated with a radioactive fracture comprises: obtaining isochronous geological slices according to the geological structure morphology map, and identifying the annular structure morphology; and determining that the annular structure morphology is a negative annular structure according to the annular structure morphology decreasing from large to small from top to bottom in space.

[0008] According to one embodiment of the present invention, the annular structure includes: a contour on a geological slice that is circular or elliptical with a ratio of a major axis to a minor axis less than 1.5.

[0009] According to one embodiment of the present invention, identifying a compressional thrust fault around the negative annular structure includes: identifying the fault at the edge of the annular structure through seismic profiles and horizontal slices; if the stratigraphic relationship of the fault is that the upper plate rises relative to the lower plate, it is identified as a compressional thrust fault.

[0010] According to one embodiment of the present invention, identifying faults through seismic sections and horizontal slices includes: intercepting a plurality of the seismic sections and the horizontal slices; and identifying faults on the seismic sections and the horizontal slices, respectively.

[0011] According to one embodiment of the present invention, the angles between the multiple seismic profiles range from 2° to 15°.

[0012] According to another aspect of the present invention, there is provided a device for identifying cover-type thrust structures formed by ancient planets impacting the Earth, comprising: a processor for executing program instructions; and a memory storing program instructions, which enables the processor to execute the aforementioned method when the program instructions are loaded and executed by the processor.

[0013] According to another aspect of the present invention, a non-volatile computer-readable storage medium is provided, on which computer-readable instructions are stored. When the computer-readable instructions are executed by one or more processors, the aforementioned method is implemented.

[0014] In the present invention, by limiting the age of identifying negative annular structures, the scope of identifying covering thrust structures formed by ancient planets impacting the earth is narrowed, the amount of data processing is reduced, and the processing speed is improved.

[0015] In the present invention, the ring structure is identified on the basis of restoring the geological structure morphology map of the high-frequency period of planetary impact using three-dimensional seismic data, which helps to realize the targeted identification of the ring structure caused by the ancient planetary impact.

[0016] In the present invention, the annular structural features, radioactive faults and thrust anticline features are used to comprehensively identify the covered thrust structures caused by ancient planetary impacts in the paleogeological structure map, thereby achieving an accurate identification effect.

[0017] The present invention can comprehensively identify the covering thrust structure caused by ancient planetary impact in the ancient structural map of the high-frequency occurrence of planetary impact, thereby improving the processing speed, improving the recognition accuracy, and overcoming the problem of difficulty in recognition caused by the interference of geological movement.

[0018] In an embodiment of the present invention, by determining the high-frequency occurrence of planetary impacts in the geological structure map, the ancient structures of each age can be reproduced, and the covering thrust structures formed by ancient planetary impacts can be accurately identified, avoiding missing the covering thrust structures affected by burial, diagenesis, structural deformation, etc. during the identification process.

[0019] Through seismic profiles and horizontal slices, faults can be identified from different angles, which helps to improve identification accuracy.

[0020] The identification accuracy is improved by utilizing multiple seismic sections and multiple horizontal slices. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] 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 invention will become readily understood. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0022] Figure 1 A schematic diagram of a three-dimensional seismic survey system is shown;

[0023] Figure 2 A schematic diagram showing the steps for identifying the overlying thrust structure formed by the impact of an ancient planet on the Earth;

[0024] Figure 3 A schematic diagram of the structural cross section formed by the impact of an ancient planet on Earth is shown;

[0025] Figure 4 Schematic diagrams showing the annular configuration and radial fractures. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0027] It should be understood that the terms "include" and "comprising" used in the description and claims of the present invention indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0028] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the claims, the singular forms of "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should also be further understood that the term "and / or" used in the specification of the present invention and the claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0029] As used in this specification and claims, the term "if" may be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" may be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

[0030] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0031] Seismic exploration is a method of geophysical exploration that uses artificially excited seismic waves to locate mineral deposits and obtain engineering geological information. Its basic principle is: artificially excited seismic sources generate seismic waves. When seismic waves propagate in rocks, if they encounter the interface of rock layers, they will generate reflected waves or refracted waves. When the reflected waves or refracted waves return to the ground, they are received by recording instruments such as geophones to form seismic data. Through the analysis, processing and comprehensive interpretation of seismic data, the burial depth and shape of the rock layer section where the seismic waves are reflected or refracted are determined, and accurate imaging of underground geological structures is achieved.

[0032] Figure 1 A schematic diagram of a three-dimensional seismic survey system is shown.

[0033] like Figure 1As shown, in the system 100, a plurality of mutually spaced detectors 110 for detecting seismic waves are arranged on the surface 101 of the exploration target area, forming a detector array covering the target area on a plane. These detectors 110 are connected to the seismic information processing device by wired or wireless connection, and a plurality of seismic sources 120 are also provided. The seismic information processing device can perform preliminary processing on the seismic data. The working process of the three-dimensional seismic exploration system is: artificially excite the seismic sources 120 located at multiple positions to generate seismic waves, which are reflected from the boundary of the stratum 102 and received by the detector array to form seismic information collected on a plane and changing with time. The seismic information received by the detector array represents certain measures of seismic wave energy as a function of time, such as displacement, velocity, wave impedance, pressure, etc. This information can be grouped in different ways, such as traces, sets, etc., and then processed or format-converted according to the corresponding relationship between time and space to form a three-dimensional seismic data body in the form of a three-dimensional array. It can also be said that the three-dimensional seismic data body is formed by stacking interface points in space. The interpretation of three-dimensional seismic data can observe the morphology of geological interfaces from different directions and study the changes of geological bodies in three-dimensional space by cutting cross sections, longitudinal sections and horizontal slices.

[0034] In the stratigraphic model, the stratigraphic layer 102 includes faults. Faults refer to the phenomenon that the stratigraphic layer undergoes relative displacement along the fracture surface and are a byproduct of tectonic activity. Faults play a very important role in controlling the migration, accumulation or destruction of oil and gas, and are closely related to the formation, distribution and enrichment of oil and gas reservoirs, and are important migration channels.

[0035] Figure 2 A schematic diagram showing the steps of a method for identifying overlying thrust structures formed by ancient planetary impacts on the Earth.

[0036] like Figure 2 As shown, the method for identifying the cover-type thrust structure formed by the impact of an ancient planet on the earth comprises: a first step S201, using underground three-dimensional seismic data to interpret and obtain a geological structure morphology map; a second step S202, in the geological structure morphology map, in the high-frequency occurrence age of planetary impacts, identifying a negative annular structure accompanied by radioactive faults, wherein the high-frequency occurrence age of planetary impacts includes: the end of the Ordovician, the end of the Devonian, the end of the Permian, the end of the Triassic and the end of the Cretaceous; a third step S203, identifying a compressional thrust fault around the negative annular structure; a fourth step S204, identifying a thrust anticline on the upper plate of the compressional thrust fault, and obtaining a cover-type thrust structure formed by the impact of an ancient planet on the earth.

[0037] The thrust structure identified in the present invention is a typical structure of an impact-type oil-generating depression, and is a type of impact structure determined based on impact stratigraphy. When the bottom of a basin generated by an impact structure has connected source rocks, it can be called an oil-generating depression.

[0038] In the early stage of geological deposition, old strata such as the end of Ordovician, the end of Devonian, the end of Permian, the end of Triassic and the end of Cretaceous were hit by meteorites or ancient planets in one or more periods, forming annular or quasi-annular depressions and a series of compressional ancient buried hills around the depressions. In the later stage, the strata were covered by sedimentation to form a buried hill oil reservoir with a good configuration of source rock and ancient buried hill closures.

[0039] In the first step, by acquiring underground three-dimensional seismic data, an underground geological structure morphology map is formed after interpretation, which is close to the morphology of the real underground stratigraphic structure. According to the relationship between the strata in the underground geological structure morphology map, the layers are flattened from near to far in chronological order. The age interval can be set as needed, and different age intervals can be set or adjusted according to the stratigraphic relationship. Each time the layer is flattened to form the corresponding ancient structure, the operation is cyclical, and ancient structures of multiple ages can be obtained, including the high-frequency age of planetary impacts, so that the cover-type thrust structure caused by ancient planetary impacts can be identified in a targeted manner in the high-frequency age of planetary impacts.

[0040] Identify negative annular structures in paleostructures from the era of frequent planetary impacts. Planetary impacts will form annular negative structural paleogeomorphic features, which are characterized by circular or elliptical annular negative structural forms, which may be accompanied by radioactive fractures. According to the seismic data of paleogeomorphic formation, the isochronous slicing technology can be used to identify circular or elliptical annular structural forms. According to the spatial top-down annular change characteristics, the negative annular structure changes from large to small, and vice versa. The negative annular structure is thus identified as a planetary impact crater. Moreover, since the impact easily forms compressive stress, a thrust structure is formed around the circular or elliptical annular negative structure. By identifying the compression thrust fault and the upper plate thrust anticline around it, the covering thrust structure formed by the impact of the ancient planet on the earth can be obtained.

[0041] Figure 3 A schematic diagram of the structural cross section formed by the impact of an ancient planet on Earth is shown;

[0042] Figure 4 Schematic diagrams showing the annular configuration and radial fractures.

[0043] like Figure 3 and Figure 4 As shown, A is an annular structure, B is a radial fault, and C is a thrust fault.

[0044] Annular structures are identified in the impact crater area and the surrounding area. Specifically, annular structures are identified on ancient structures of multiple ages when planetary impacts occurred frequently, and the information of these annular structures is summarized to form a first structure set. The first structure set contains the annular structures identified in each ancient structure. Even if these annular structures are no longer circular or elliptical due to later stratum movement, their circular or elliptical structures can be restored according to the different ancient structures in each period, thereby avoiding missing deformed annular structures.

[0045] like Figure 3 and Figure 4 As shown, the annular structure A in the first structure set is screened, and the screening condition is set to the presence of radial faults B in the surrounding area. The annular structure with radial faults has the conditions for forming oil and gas channels and oil and gas traps. By setting this condition to further screen the annular structure, the oil and gas probability of the thrust fault finally identified can be increased.

[0046] Identify compressional thrust faults at the edge of the annular structure. Identify faults through seismic sections and horizontal slices; if the stratigraphic relationship of the fault is that the upper plate rises and the lower plate falls, it is identified as a compressional thrust fault. Preferably, multiple seismic sections are intercepted; multiple horizontal slices are intercepted; and faults are identified on the seismic sections and the horizontal slices respectively. The seismic section is a longitudinal section with time as the ordinate and offset as the abscissa, and the horizontal slice is a slice in the horizontal direction at a certain time point. Usually, the seismic section and the horizontal slice are perpendicular to each other.

[0047] By identifying compression thrust faults on seismic sections and horizontal slices, respectively, omissions caused by different angles of interception of seismic sections or horizontal slices can be avoided. In order to further avoid omissions, multiple seismic sections and / or multiple horizontal slices can be taken to verify each other and identify faults. Multiple seismic sections can be parallel to each other or can be set to have a certain angle between each other. Preferably, the angle range between the multiple seismic sections is 2-15°. By setting an angle between the two, omissions of fault identification caused by the interception angle of the seismic section can be avoided.

[0048] Anticline trap refers to a stratigraphic structure that can form oil and gas reservoirs. It is a closed geological structure that can accumulate oil and natural gas because the top of the reservoir is arched upward and its upper part is covered and blocked by impermeable rock layers. Anticline has the following characteristics: the rock layer or fault surface is inclined to both sides and rises toward the center; the dip angle of the anticline is usually steep, generally between 30 and 70 degrees.

[0049] When determining the range of anticline traps, the range can be determined as the range extending from the inside and edge of the annular structure to a certain distance, such as 50 km. At the edge of the annular structure, due to the impact, anticline traps may be generated, and migration channels connecting the anticline traps in this range and the source rocks at the bottom are easily generated.

[0050] When identifying anticline traps, anticline traps with inclined axial planes are preferred. Specifically, in the three-dimensional seismic data volume, the axial plane of the anticline is marked, and the angle of the axial plane relative to the horizontal plane is calculated. When the angle is 90°, it indicates that it is located in the vertical direction, and when the angle is not equal to 90°, it indicates that it is in an inclined state. The bottom of the anticline trap with inclined axial plane is conducive to connecting with the migration channel, which is an advantageous luck reservoir structure.

[0051] Migration pathways refer to the paths of oil and gas migration, including networks of pores, dissolved pores, caves and cracks connecting anticline traps and source rocks, faults or fracture zones, unconformities, etc. Oil and gas resources are generated from source rocks and are enriched in anticline traps through these migration pathways to form oil and gas reservoirs.

[0052] In the present invention, by limiting the age of identifying negative annular structures, the scope of identifying thrust structures formed by ancient planets impacting the earth is narrowed, the amount of data processing is reduced, and the processing speed is improved.

[0053] In the present invention, the ring structure is identified on the basis of restoring the geological structure morphology map of the high-frequency period of planetary impact using three-dimensional seismic data, which helps to realize the targeted identification of the ring structure caused by the ancient planetary impact.

[0054] In the present invention, the annular structural features, radioactive faults and thrust anticline features are used to comprehensively identify the covered thrust structures caused by ancient planetary impacts in the paleogeological structure map, thereby achieving an accurate identification effect.

[0055] In an embodiment of the present invention, by determining the high-frequency occurrence of planetary impacts in the geological structure map, the ancient structures of each age can be reproduced, and the covering thrust structures formed by ancient planetary impacts can be accurately identified, avoiding missing the covering thrust structures affected by burial, diagenesis, structural deformation, etc. during the identification process.

[0056] Through seismic profiles and horizontal slices, faults can be identified from different angles, which helps to improve identification accuracy.

[0057] The accuracy of identification is improved by utilizing multiple seismic sections and multiple horizontal slices.

[0058] The present invention can comprehensively identify the covering thrust structure caused by ancient planetary impact in the ancient structural map of the high-frequency occurrence of planetary impact, thereby improving the processing speed, improving the recognition accuracy, and overcoming the problem of difficulty in recognition caused by the interference of geological movement.

[0059] Although multiple embodiments of the present invention have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art may conceive of many changes, modifications, and alternatives without departing from the thought and spirit of the present invention. It should be understood that in the process of practicing the present invention, various alternatives to the embodiments of the present invention described herein may be adopted. The appended claims are intended to define the scope of protection of the present invention, and therefore cover equivalents or alternatives within the scope of these claims.

Claims

1. A method for identifying a cover-type thrust structure formed by an ancient planet impacting the Earth, characterized in that: include: The first step is to use underground three-dimensional seismic data to interpret and obtain a geological structure morphology map; The second step is to identify negative annular structures with radioactive fractures in the high-frequency occurrence of planetary impacts in the geological structure morphology map, wherein the high-frequency occurrence of planetary impacts includes: the end of the Ordovician, the end of the Devonian, the end of the Permian, the end of the Triassic and the end of the Cretaceous; The third step is to identify compressional thrust faults around the negative annular structure; The fourth step is to identify the thrust anticline in the upper plate of the compressional thrust fault to obtain the covering thrust structure formed by the impact of the ancient planet on the earth.

2. The method according to claim 1, characterized in that In the first step, using underground three-dimensional seismic data to interpret and obtain a geological structure morphology map includes: According to the underground three-dimensional seismic data, the paleo-geomorphological seismic geological data are restored to obtain a geological structure morphology map.

3. The method according to claim 1, characterized in that In the second step, identifying the negative annular structure associated with radioactive fractures includes: According to the geological structure morphology map, isochronous geological slices are obtained to identify the annular structure morphology; According to the fact that the annular structure morphology changes from large to small from top to bottom in space, it is determined that the annular structure morphology is a negative annular structure.

4. The method according to claim 3, characterized in that The annular structure includes: a contour on a geological slice that is circular or an ellipse with a ratio of a major axis to a minor axis less than 1.

5.

5. The method according to claim 3, characterized in that: Identification of compressional thrust faults around the negative annular structure includes: At the edges of the ring structure, faults were identified by seismic profiles and horizontal slices; If the stratigraphic relationship of the fault is that the hanging wall rises relative to the footwall, it is identified as a compressional thrust fault.

6. The method according to claim 5, characterized in that Identification of faults through seismic sections and horizontal slices includes: intercepting a plurality of the seismic sections and the horizontal slices; Faults are identified on the seismic profile and the horizontal slice, respectively.

7. The method according to claim 6, characterized in that The angles between the multiple seismic profiles range from 2° to 15°.

8. A device for identifying the overlying thrust structure formed by the impact of an ancient planet on the Earth, characterized in that: include: a processor for executing program instructions; and a memory storing program instructions, which, when loaded and executed by a processor, enables the processor to execute the method according to any one of claims 1 to 7.

9. A non-volatile computer-readable storage medium, characterized in that: Computer-readable instructions are stored thereon, and when the computer-readable instructions are executed by one or more processors, the method according to any one of claims 1 to 7 is implemented.

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