Method and system for obtaining stratum extrusion shortening amount

Abstract

The invention discloses a method and system for obtaining stratum extrusion shortening amount, and the method comprises the steps: obtaining the areas of uplift region sections of different layers in a stratum to be researched, and the size parameters of rigid stratum region sections of corresponding layers, the uplift area section and the rigid rock stratum area section are both seismic sections perpendicular to the ground and parallel to the stratum compression direction; and the thickness parameter in the size parameters of the rigid rock stratum area section is extracted to determine the slip surface depth, and the slip surface depth and the area of the uplift area section are subjected to linear fitting, so that the extrusion shortening amount of the stratum to be researched is obtained according to the fitting result. According to the invention, accurate acquisition of the formation extrusion shortening amount is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of geological exploration, and in particular relates to a method and system for obtaining the formation squeeze shortening amount. Background Art

[0002] The calculation of formation shortening amount has always been a difficult problem in structural geology. Affected by the data quality and the large scale of the research scope of structural geology, there is a lack of a method that can clearly and quantitatively restore the regional formation shortening amount. At the same time, during the process of formation squeeze shortening deformation, weak layers (such as gypsum-salt layers), rheology and extrusion activities are complex, and plastic rheology will occur. The appearance of this phenomenon causes difficulties in calculating the squeeze shortening amount deformation. The existing technology generally obtains the squeeze shortening amount by simple estimation, ignoring the uncertainty brought by the rheology in the weak layer area. However, in fact, the rheology in the weak layer area can absorb the deformation amount of regional tectonic activities and has a significant impact on the regional deformation behavior. Ignoring the rheology in the weak layer area to calculate the squeeze shortening amount often cannot obtain reliable data. Therefore, there is an urgent need for a method for restoring the formation squeeze shortening amount considering the plastic rheology of gypsum-salt layers in areas with weak layer rocks. Summary of the Invention

[0003] In order to solve the above problems, an embodiment of the present invention provides a method for obtaining the formation squeeze shortening amount, including: obtaining the area of the uplift area profile of different horizons in the formation to be studied, and the size parameters of the rigid rock layer area profile corresponding to the horizons, wherein the uplift area profile and the rigid rock layer area profile are both seismic profiles perpendicular to the ground and parallel to the formation compression direction; extracting the thickness parameter in the size parameters of the rigid rock layer area profile to determine the detachment surface depth, and performing a linear fit on the detachment surface depth and the area of the uplift area profile, so as to obtain the squeeze shortening amount of the formation to be studied according to the fitting result.

[0004] Preferably, in the step of obtaining the area of the uplift area profile of different horizons in the formation to be studied, it includes: determining the development positions of the weak layer areas of different horizons according to the seismic data volume of the formation to be studied, and analyzing the material rheological characteristics of the weak layer areas of each horizon, so as to obtain the uplift area corresponding to the weak layer area of each horizon according to the analysis result, and then obtain the corresponding area.

[0005] Preferably, in the step of fitting the detachment surface depth and the area of the uplift area profile, it includes: based on the correlation between the area of the uplift area profile of different horizons and the area of the compression area profile, obtaining the shortening amount for calculating the area of the compression area profile of each horizon and the correlation between the detachment surface depth and the area of the uplift area profile, and thus performing a fit on the detachment surface depth and the area of the uplift area profile.

[0006] Preferably, the correlation between the area of the uplift zone profile and the area of the compression zone profile at different stratigraphic levels is an equal-area relationship.

[0007] Preferably, the area of the compression zone profile is obtained by calculating the product of the shortening amount and the depth of the detachment surface.

[0008] Preferably, in the step of obtaining the compressive shortening amount of the formation to be studied, it includes: extracting the slope of the fitting line from the fitting result and taking the slope as the compressive shortening amount of the formation to be studied.

[0009] Preferably, the fitting line is represented by the following expression:

[0010] ΔA = S / AH

[0011] where S represents the compressive shortening amount, △H represents the depth of the detachment surface, and △A represents the area of the uplift zone profile.

[0012] Preferably, the dimensional parameters of the rigid rock formation area profile include but are not limited to: length, thickness, and area.

[0013] The present invention also provides a computer-readable storage medium, which contains a series of instructions for performing the method steps of obtaining the compressive shortening amount of the formation.

[0014] On the other hand, the present invention also provides a system for obtaining the compressive shortening amount of the formation. The system includes the following modules: a parameter acquisition module, which is used to acquire the area of the uplift zone profile at different stratigraphic levels in the formation to be studied, and the dimensional parameters of the rigid rock formation area profile corresponding to the stratigraphic levels, where the uplift zone profile and the rigid rock formation area profile are both seismic profiles perpendicular to the ground and parallel to the formation compression direction; a shortening amount calculation module, which is used to extract the thickness parameter in the dimensional parameters of the rigid rock formation area profile to determine the depth of the detachment surface, and perform a linear fit on the depth of the detachment surface and the area of the uplift zone profile, so as to obtain the compressive shortening amount of the formation to be studied according to the fitting result.

[0015] The present invention provides a method and system for obtaining the formation compaction shortening amount. The method mainly uses seismic-geological analysis, applies the theory of conservation of gypsum-salt rheological substances in the field of salt structure research to the calculation of formation shortening amount. First, obtain the area of the uplifted area profile and the size parameters of the rigid rock layer area profile in the formation to be studied, then extract the thickness parameter from the size parameters of the rigid rock layer area profile to determine the detachment surface depth, and obtain the compaction shortening amount of the formation to be studied by linearly fitting the detachment surface depth and the area of the uplifted area profile. The present invention breaks through the technical difficulty of accurately calculating the regional formation shortening amount, realizes the accurate acquisition of the formation compaction shortening amount, and has important significance for studying the compaction shortening of gypsum-salt-bearing formations.

[0016] Other features and advantages of the present invention will be described in the following specification, and part of them will be obvious from the specification or understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the specification, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention. In the drawings:

[0018] Figure 1 is a step diagram of the method for obtaining the formation compaction shortening amount according to the embodiment of the present application.

[0019] Figure 2 is an example diagram of the uplifted area and the compressed area of the method for obtaining the formation compaction shortening amount according to the embodiment of the present application.

[0020] Figure 3 is an example diagram of the fitting line of the method for obtaining the formation compaction shortening amount according to the embodiment of the present application.

[0021] Figure 4 is a module block diagram of the system for obtaining the formation compaction shortening amount according to the embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The following will describe the embodiments of the present invention in detail with reference to the drawings and embodiments, so as to fully understand how the present invention uses technical means to solve technical problems and achieve the implementation process of technical effects. It should be noted that as long as there is no conflict, the various embodiments in the present invention and the various features in each embodiment can be combined with each other, and the formed technical solutions are all within the protection scope of the present invention.

[0023] In addition, the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. And although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0024] The calculation of formation shortening has always been a difficult problem in structural geology. Affected by the data quality and the relatively large scale of the research scope of structural geology, there is a lack of a method to clearly and quantitatively restore the regional formation shortening. At the same time, during the process of squeezing and shortening deformation of the formation, in soft layers (such as gypsum-salt layers), the rheology and extrusion activities are complex, and plastic rheology will occur. The occurrence of this phenomenon causes difficulties in calculating the squeezing and shortening deformation. The existing technology generally obtains the squeezing and shortening amount by simple estimation, ignoring the uncertainty brought by the rheology in the soft layer area. However, in fact, the rheology in the soft layer area can absorb the deformation amount of regional tectonic activities and has a significant impact on the regional deformation behavior. Calculating the squeezing and shortening amount by ignoring the rheology in the soft layer area often fails to obtain reliable data. Therefore, there is an urgent need for a method for restoring the formation squeezing and shortening amount considering the plastic rheology of gypsum-salt layers in areas with soft layer rocks.

[0025] Therefore, to solve the above problems, embodiments of the present invention propose a method and system for obtaining the formation squeezing and shortening amount. This method takes seismic-geological analysis as the main means, applies the theory of material conservation of gypsum-salt rheology in the field of salt tectonics research to the calculation of formation shortening amount, first obtains the area of the uplifted area profile and the size parameters of the rigid rock layer area profile in the formation to be studied, then extracts the thickness parameter in the size parameters of the rigid rock layer area profile to determine the detachment surface depth, and obtains the squeezing and shortening amount of the formation to be studied by linearly fitting the detachment surface depth and the area of the uplifted area profile. The present invention breaks through the technical difficulty of accurately calculating the regional formation shortening amount, realizes the accurate acquisition of the formation squeezing and shortening amount, and is of great significance for studying the squeezing and shortening of gypsum-salt-bearing formations.

[0026] Example 1

[0027] Rheological properties refer to the quantitative relationship between the strain and stress that occur in an object under the action of an external force. This strain (flow or deformation) is related to the nature and internal structure of the object, as well as the relative motion state between the particles within the object. Real objects (or materials) will undergo deformation (or flow) under the action of an external force. According to their properties, the deformation can be divided into elastic deformation, viscous flow, and plastic flow. Rigid rocks such as carbonate rocks and sandstones mainly undergo elastic deformation under the stress at common temperature and pressure conditions in nature. When the stress exceeds a certain threshold, the rock will fracture and form faults. However, gypsum salts, due to their weak ability to dry, undergo plastic flow when subjected to stress. After the stress is removed, the deformation will not recover (i.e., non-elastic deformation), and there is no fracture within the gypsum salt layer. The rheological properties of gypsum salts cause a natural law of movement from high-stress areas to low-stress areas when they are subjected to stress, resulting in completely different structural styles from those of rigid strata such as carbonate rocks and sandstones. In areas where gypsum salt layers are developed, the tectonic deformation behavior often presents a layered structural style from top to bottom, that is, the structural styles above and below the salt are inconsistent.

[0028] Figure 1 This is a step diagram of the method for obtaining the formation squeeze shortening amount in the embodiments of the present application. The following will refer to Figure 1 to illustrate each step of this method.

[0029] As Figure 1 shown, in step S110, the area of the uplift region profile at different horizons in the formation to be studied is obtained, as well as the size parameters of the rigid rock formation region profile corresponding to the horizons. Among them, both the uplift region profile and the rigid rock formation region profile are seismic profiles perpendicular to the ground and parallel to the formation compression direction. Based on the foregoing analysis, it can be known that during the squeeze shortening process of the gypsum salt-bearing formation, the size parameters of the rigid rock formation remain unchanged, while the soft layer (such as the gypsum salt layer) will form an uplift region due to plastic flow. Therefore, in this embodiment, the uplift regions and rigid rock formation regions at different horizons in the formation to be studied containing soft layers (such as gypsum salt-bearing formations) are determined, and the area of the uplift region profile and the size parameters of the rigid rock formation region profile for each horizon are obtained. For the convenience of measurement and calculation, in this embodiment, a seismic profile perpendicular to the ground and parallel to the formation compression direction is selected as the uplift region profile and the rigid rock formation region profile.

[0030] In a specific embodiment of the present application, the size parameters of the rigid rock formation region profile include but are not limited to: length, thickness, and area. That is to say, in this embodiment, based on the characteristics that the length, thickness, and area (shortening) of the rigid rock formation in the formation to be studied remain unchanged before and after the squeeze shortening process, the acquisition of the formation squeeze shortening amount is realized, ensuring the reliability of the obtained formation squeeze shortening amount.

[0031] In the step of obtaining the areas of the uplifted area profiles at different horizons in the formation to be studied, based on the seismic data volume of the formation to be studied, determine the development positions of the weak layer areas at different horizons, and analyze the material rheological characteristics of the weak layer areas at each horizon. Then, according to the analysis results, obtain the uplifted areas corresponding to the weak layer areas at each horizon, and further obtain the corresponding areas. Figure 2 This is an example diagram of the uplifted area and the compressed area of the method for obtaining the formation compression shortening amount according to the embodiment of the present application. Refer to Figure 2 , in this embodiment, by collecting the basic geological data of the formation to be studied, determine the basic situation of the geological structure. Then, on the seismic data volume of the formation to be studied, intercept the seismic profile parallel to the thrust direction, so as to obtain the development positions of the weak layer areas at different horizons according to the intercepted seismic profile, and on this basis, analyze the material rheological characteristics of the weak layer areas at each horizon, so as to clarify the situation of the material rheology of the weak layer. Finally, according to the situation of the material rheology of the weak layer, locate the uplifted areas corresponding to the weak layer areas at each horizon, and thus use the shortening amount S and the detachment surface depth H d to calculate the shortening area A s and then obtain the area A of the uplifted area profile.

[0032] Furthermore, in step S120, extract the thickness parameter in the size parameters of the rigid rock layer area profile to determine the detachment surface depth, and perform a linear fit on the detachment surface depth and the area of the uplifted area profile. Then, according to the fitting result, obtain the compression shortening amount of the formation to be studied. Since there are large errors in the amount of the detachment fold shortening area calculated by using the area balance method of a single horizon, in this embodiment, on the basis of the area balance method, by establishing a linear fitting line between the areas of the uplifted areas at multiple horizons and the distance from the initial sedimentary surface of the formation to the detachment layer or the height from the detachment layer (detachment surface depth), obtain the compression shortening amount that matches the entire formation to be studied. In the embodiment of the present application, based on the correlation between the uplifted area and the compressed area on the same horizon, extract the thickness parameter in the size parameters of the rigid rock layer area profile to determine the detachment surface depth, and further establish the correlation between the detachment surface depth and the area of the uplifted area profile, and accordingly implement the linear fit. Then, according to the fitting result, obtain the compression shortening amount of the formation to be studied. It can be seen that the present invention obtains the accurate formation shortening amount on the seismic profile by quantitatively calculating the material flow variable of the weak layer.

[0033] In the step of fitting the depth of the detachment surface and the area of the uplift region profile, based on the correlation between the area of the uplift region profile and the area of the compression region profile at different horizons, the shortening amount used to calculate the area of the compression region profile and the correlation between the depth of the detachment surface and the area of the uplift region profile are obtained for each horizon, thereby fitting the depth of the detachment surface and the area of the uplift region profile. In the embodiment of the present application, according to the correlation between the area of the uplift region profile and the area of the compression region profile at different horizons, combined with the positional relationship between the compression region and the adjacent rigid rock formation region, that is, there is a common edge between the compression region and the rigid rock formation region at each horizon. At this time, the depth of the detachment surface can be determined according to the length of the common edge, so that a specific relationship is also formed between the depth of the detachment surface and the area of the uplift region profile. Integrating the depths of the detachment surface and the areas of the uplift region profiles at different horizons into the same coordinate system can achieve the purpose of linearly fitting the depth of the detachment surface and the area of the uplift region profile.

[0034] Next, the correlation between the area of the uplift region profile and the area of the compression region profile at different horizons is an area equality relationship. Specifically, due to the conservation of the rheological area of the weak layer region, the area of the formation compression region caused by extrusion will be completely converted into the uplift region area. Therefore, in this embodiment, the area equality relationship is used as the correlation between the area of the uplift region profile and the area of the compression region profile at different horizons.

[0035] Furthermore, the area of the compression region profile is obtained by calculating the product of the shortening amount and the depth of the detachment surface. Based on the foregoing analysis, it can be seen that the depth of the detachment surface is related to the length of the common edge between the compression region and the rigid rock formation region. The product of the length of the common edge and the shortening amount of the compression region within a single horizon is the area of the compression region profile of that horizon. For multiple horizons in this embodiment, the product of the shortening amount and the depth of the detachment surface is used, combined with the area of the compression region of the single horizon where the initial sedimentary surface is located, to calculate the areas of the compression region profiles at different horizons.

[0036] In the step of obtaining the extrusion shortening amount of the formation to be studied, the slope of the fitting line is extracted from the fitting result, and the slope is used as the extrusion shortening amount of the formation to be studied. Figure 3 This is an example diagram of the fitting line of the method for obtaining the extrusion shortening amount of the formation in the embodiment of the present application. As Figure 3 shown, in a specific embodiment of the present application, a total of 8 horizons are selected, and the uplift region areas and the corresponding detachment surface depths of 8 are measured respectively (the growth formation phenomenon appears in horizons 1 to 3, indicating multi-stage extrusion activities, which need to be excluded during subsequent data fitting). The uplift region area is linearly fitted with the detachment surface depth as the detachment thickening area, and the calculated slope of the fitting line is 2.67. At this time, the extrusion shortening amount of the current formation is obtained as 2.67 km.

[0037] In the embodiment of the present application, the fitting straight line is represented by the following expression:

[0038] AA = S / AH (1)

[0039] Wherein, S represents the extrusion shortening amount, ΔH represents the depth of the slip surface, and ΔA represents the area of the profile of the uplifted area.

[0040] In summary, the present invention is based on the rheological material conservation in the weak layer area, and based on the fine seismic-geological analysis, the kinematic characteristics of the weak layer area are determined, so as to finely depict the kinematic characteristics of the nearby layers developed in the weak layer area. By quantitatively counting the areas of the uplifted areas of different layers and defining the depths of the slip surfaces of different layers, the amount of the formation shortening area is quantitatively calculated, thereby realizing the accurate calculation of the extrusion shortening amount of the formation.

[0041] Example 2

[0042] The embodiment of the present invention also provides a computer-readable storage medium, in which at least one instruction is stored, and the instruction is loaded and executed by a processor to implement the operation of obtaining the extrusion shortening amount of the formation in the method of the above embodiment. For example, the computer-readable storage medium may be a ROM (Read Only Memory), a RAM (Random Access Memory), a CD-ROM (Compact Disc-Read Only Memory), a magnetic tape, a floppy disk, an optical data storage device, etc.

[0043] Example 3

[0044] Based on the method for obtaining the extrusion shortening amount of the formation described in the above Embodiment 1, the embodiment of the present invention also provides a system for obtaining the extrusion shortening amount of the formation. Figure 4 It is a block diagram of the module of the system for obtaining the extrusion shortening amount of the formation in the embodiment of the present application.

[0045] As Figure 4As shown in the figure, the system for obtaining the formation squeeze shortening amount in the embodiments of the present invention includes: a parameter acquisition module 41 and a shortening amount calculation module 42. Specifically, the parameter acquisition module 41 is implemented according to the method described in step S110 above, and is configured to obtain the area of the uplift area profile of different horizons in the formation to be studied, and the size parameters of the rigid rock formation area profile corresponding to the horizons, wherein both the uplift area profile and the rigid rock formation area profile are seismic profiles perpendicular to the ground and parallel to the formation compression direction; the shortening amount calculation module 42 is implemented according to the method described in step S120 above, and is configured to extract the thickness parameter in the size parameters of the rigid rock formation area profile to determine the detachment surface depth, and perform a linear fit on the detachment surface depth and the area of the uplift area profile, so as to obtain the squeeze shortening amount of the formation to be studied according to the fitting result.

[0046] The present invention discloses a method and a system for obtaining the formation squeeze shortening amount. The method mainly uses seismic-geological analysis, applies the theory of the conservation of gypsum-salt rheological substances in the field of salt structure research to the calculation of the formation shortening amount, first obtains the area of the uplift area profile and the size parameters of the rigid rock formation area profile in the formation to be studied, then extracts the thickness parameter in the size parameters of the rigid rock formation area profile to determine the detachment surface depth, and obtains the squeeze shortening amount of the formation to be studied by performing a linear fit on the detachment surface depth and the area of the uplift area profile. The present invention breaks through the technical difficulty of accurately calculating the regional formation shortening amount, realizes the accurate acquisition of the formation squeeze shortening amount, and has important significance for studying the squeeze shortening situation of the gypsum-salt-bearing formation.

[0047] As mentioned above, only the specific preferred embodiments of the present invention are described, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

[0048] Of course, the present invention may also have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding changes and deformations should all fall within the protection scope of the claims of the present invention.

[0049] Those skilled in the art should understand that the various modules or steps of the present invention described above can be implemented by a general-purpose computing device. They can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Optionally, they can be implemented by program code executable by the computing device. Thus, they can be stored in a storage device and executed by the computing device, or they can be separately fabricated into individual integrated circuit modules, or multiple modules or steps among them can be fabricated into a single integrated circuit module for implementation. In this way, the present invention is not limited to any specific combination of hardware and software.

[0050] Although the embodiments disclosed in the present invention are as described above, the content described is only an embodiment adopted for the convenience of understanding the present invention and is not intended to limit the present invention. Any person skilled in the art within the technical field to which the present invention pertains can make any modifications and changes in the form of implementation and details without departing from the spirit and scope disclosed by the present invention. However, the scope of patent protection of the present invention shall still be subject to the scope defined by the appended claims.

Claims

1. A method for obtaining the formation compaction shortening amount, characterized in that, Including: Obtaining the areas of the uplift region profiles of different horizons in the formation to be studied, and the dimensional parameters of the rigid rock layer region profiles corresponding to the respective horizons, where the uplift region profiles and the rigid rock layer region profiles are both seismic profiles perpendicular to the ground and parallel to the formation compression direction; Extracting the thickness parameter among the dimensional parameters of the rigid rock layer region profiles to determine the detachment surface depth, and performing linear fitting on the detachment surface depth and the area of the uplift region profile, so as to obtain the compressive shortening amount of the formation to be studied according to the fitting result.

2. The method according to claim 1, wherein In the step of obtaining the areas of the uplift region profiles of different horizons in the formation to be studied, it includes: Based on the seismic data volume of the formation to be studied, determining the development positions of the weak layer regions of different horizons, and analyzing the material rheological characteristics of the weak layer regions of each horizon, so as to obtain the uplift regions corresponding to the weak layer regions of each horizon according to the analysis result, and further obtain the corresponding areas.

3. The method according to claim 1 or 2, characterized in that, In the step of fitting the detachment surface depth and the area of the uplift region profile, it includes: Based on the correlation relationship between the area of the uplift region profile and the area of the compression region profile of different horizons, obtaining the shortening amount for calculating the area of the compression region profile of each horizon and the correlation relationship between the detachment surface depth and the area of the uplift region profile, and thereby fitting the detachment surface depth and the area of the uplift region profile.

4. The method according to claim 3, characterized in that, The correlation relationship between the area of the uplift region profile and the area of the compression region profile of different horizons is an area equality relationship.

5. The method according to claim 4, wherein The area of the compression region profile is obtained by calculating the product of the shortening amount and the detachment surface depth.

6. The method according to claim 5, wherein In the step of obtaining the compressive shortening amount of the formation to be studied, it includes: Extracting the slope of the fitting line from the fitting result, and taking the slope as the compressive shortening amount of the formation to be studied.

7. The method according to claim 6, wherein The fitting line is represented by the following expression: ΔA = S / ΔH where S represents the compressive shortening amount, ΔH represents the detachment surface depth, and ΔA represents the area of the uplift region profile.

8. The method according to any one of claims 1 to 7, characterized in that, The dimensional parameters of the rigid rock layer region profile include but are not limited to: length, thickness, and area.

9. A computer-readable storage medium, characterized in that, It includes a series of instructions for executing the method steps for obtaining the compressive shortening amount of the formation as described in any one of claims 1 to 8.

10. A system for obtaining the formation squeeze shortening amount, characterized in that, The system includes the following modules: A parameter acquisition module, which is used to obtain the areas of the uplift region profiles of different horizons in the formation to be studied, and the dimensional parameters of the rigid rock layer region profiles corresponding to the respective horizons, where the uplift region profiles and the rigid rock layer region profiles are both seismic profiles perpendicular to the ground and parallel to the formation compression direction; A shortening amount calculation module, which is used to extract the thickness parameter among the dimensional parameters of the rigid rock layer region profiles to determine the detachment surface depth, and perform linear fitting on the detachment surface depth and the area of the uplift region profile, so as to obtain the compressive shortening amount of the formation to be studied according to the fitting result.

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