Earthquake elastic parameter-based shale content determination method and device

Abstract

The invention discloses a shale content determination method and device based on seismic elastic parameters. The method comprises the following steps: determining a distance between a point to be estimated and a first template line in a longitudinal and transverse wave impedance two-dimensional coordinate system according to longitudinal and transverse wave impedance of the point to be estimated; according to the distance, the standard distance between the first template line and the second template line and the difference value between the shale content corresponding to the first template line and the shale content corresponding to the second template line, the shale content of the point to be estimated is determined in the mode that the distance and the shale content difference are equal in proportion, the first template line and the second template line are two parallel straight lines in a coordinate system, the shale content of each point on the first template line is the same, and the shale content of each point on the second template line is the same. According to the method, the shale content can be quantitatively calculated based on seismic elastic parameter inversion data (longitudinal wave impedance and transverse wave impedance), the operability is high, the precision is high, and the method can be better applied to production.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas geophysical prospecting and well logging, and in particular to a method and device for determining mud content based on seismic elastic parameters. Background Art

[0002] The accurate prediction of shale content (Vsh) has a certain impact on the prediction of other reservoir parameters, drilling design and wellbore stability evaluation. It can be said that accurate prediction results of shale content play an important role in finding high-quality oil and gas reservoirs.

[0003] At present, there are two main methods for using seismic data to quantitatively predict shale content: (1) directly construct the relationship between shale content and elastic curves such as longitudinal wave impedance by fitting well logging data, and apply this relationship to the elastic data volume for the prediction of the entire shale content. (2) construct the relationship between shale content and elastic parameters through the method of inverse rock physics modeling, and apply this relationship to the prediction of shale content. Summary of the invention

[0004] The inventors found that the above methods are difficult to use in the actual production of mud content. The reasons are: the first method is simple and easy, but the linear or nonlinear relationship of regression is difficult to apply to the seismic inversion data body, because the seismic inversion seismic data body can often only obtain parameters such as longitudinal wave impedance and transverse wave impedance; the second method is advanced in theory, but involves many calculation parameters, which leads to instability in the solution process and is difficult to operate in practice.

[0005] In order to at least partially solve the technical problems existing in the prior art, the inventors have made the present invention, and through a specific implementation method, provide a method and device for determining the mud content based on seismic elastic parameters. The method and device can quantitatively calculate the mud content based on the seismic elastic parameter inversion data (longitudinal wave impedance, transverse wave impedance), have strong operability and high accuracy, and can be better applied to production.

[0006] In a first aspect, an embodiment of the present invention provides a method for determining shale content based on seismic elastic parameters, comprising:

[0007] Determine the distance between the point to be estimated and the first template line in the two-dimensional coordinate system of the longitudinal and transverse wave impedances according to the longitudinal and transverse wave impedances of the point to be estimated;

[0008] According to the distance, the standard distance between the first template line and the second template line, and the difference between the mud content corresponding to the first template line and the mud content corresponding to the second template line, the mud content of the point to be estimated is determined in a manner that the distance is proportional to the mud content difference, wherein the first template line and the second template line are two parallel straight lines in the coordinate system, the mud content of each point on the first template line is the same, and the mud content of each point on the second template line is the same.

[0009] In a second aspect, an embodiment of the present invention provides a device for determining shale content based on seismic elastic parameters, comprising:

[0010] A distance determination module, used to determine the distance between the point to be estimated and the first template line in the two-dimensional coordinate system of longitudinal and transverse wave impedances according to the longitudinal and transverse wave impedances of the point to be estimated;

[0011] A mud content determination module is used to determine the mud content of the point to be estimated in a proportional manner according to the distance, the standard distance between the first template line and the second template line, and the difference between the mud content corresponding to the first template line and the mud content corresponding to the second template line, wherein the first template line and the second template line are two parallel straight lines in the coordinate system, the mud content of each point on the first template line is the same, and the mud content of each point on the second template line is the same.

[0012] In a third aspect, an embodiment of the present invention provides a computer storage medium, wherein the computer storage medium stores computer executable instructions, and when the computer executable instructions are executed by a processor, the above-mentioned method for determining mud content based on seismic elastic parameters is implemented.

[0013] In a fourth aspect, an embodiment of the present disclosure provides a server, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for determining the mud content based on seismic elastic parameters is implemented.

[0014] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0015] The method for determining the mud content based on seismic elastic parameters provided in an embodiment of the present invention directly starts from the seismic elastic parameter inversion data (longitudinal wave impedance, transverse wave impedance), pre-establishes a seismic elastic parameter interpretation template line for mud content interpretation, and calculates the mud content by solving the distance between the point to be estimated and the template line. This method has strong operability and high accuracy, and can be better applied to production.

[0016] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0017] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 This is a flow chart of a method for establishing a template line for seismic elastic parameter interpretation in Embodiment 1 of the present invention;

[0020] Figure 2 A schematic diagram of a template line established in the first embodiment of the present invention;

[0021] Figure 3 This is a flow chart of a method for determining shale content based on seismic elastic parameters in Embodiment 2 of the present invention;

[0022] Figure 4 This is a schematic diagram of the calculation result of the mud content in the second embodiment of the present invention;

[0023] Figure 5 It is a schematic diagram of the structure of a device for determining mud content based on seismic elastic parameters in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0025] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0026] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which the invention belongs. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0027] Embodiment 1

[0028] Embodiment 1 of the present invention provides a method for establishing a template line for seismic elastic parameter interpretation, and the process thereof is as follows Figure 1 As shown, the following steps are included:

[0029] Step S11: Based on the first sample set, a rock physics model characterizing the relationship between shale content, porosity and P- and S-wave velocities is established through multivariate linear regression.

[0030] Each sample of the first sample set contains the shale content, porosity, P-wave velocity and S-wave velocity of the same location, which are obtained through rock physics experiments and / or well logging data.

[0031] Based on the first sample set, a rock physics model characterizing the relationship between shale content, porosity and P- and S-wave velocities was established by multivariate linear regression as follows:

[0032] V P =AB·φ-C·V sh (1)

[0033] V S =DE·φ-FV sh (2)

[0034] In formulas (1) and (2), V P is the longitudinal wave velocity, V S is the shear wave velocity, φ is the porosity, V sh is the mud content, A, B, C, D, E and F are fitting constants.

[0035] Step S12: Based on the second sample set, a third sample set is obtained by using the conversion relationship between P-wave velocity and P-wave impedance and the rock physics model.

[0036] Each sample of the second sample set contains the shale content and porosity at the same location, and each sample of the third sample set contains the shale content, porosity, longitudinal wave impedance and shear wave impedance at the same location.

[0037] Using the rock physics model, the third sample set is obtained through the following equations (3)-(5):

[0038] I P =V P ·ρ (3)

[0039] I S =V S ·ρ (4)

[0040] ρ=ρ ma *(1-V sh -φ)+ρ sh *V sh +ρ f *φ (5)

[0041] In formulas (3)-(5), ρ ma , sh and ρ f are the known densities of pure sandstone, pure mudstone and fluid, ρ is the reservoir density, I S is the shear wave impedance, I P is the longitudinal wave impedance.

[0042] There are relatively few sample points containing mud content, porosity, longitudinal wave impedance and transverse wave impedance that can be directly obtained in the study area. Through the rock physics model, the sample points containing mud content and porosity can be obtained, and the sample points containing mud content, porosity, longitudinal wave impedance and transverse wave impedance can be calculated, thereby expanding the number of samples in the third sample set.

[0043] Step S13: Determine multiple mud content values, extract multiple sub-sample sets from the third sample set, each sub-sample set corresponds to a mud content value, and project each sub-sample set into a longitudinal and transverse wave impedance two-dimensional coordinate system with longitudinal wave impedance as the horizontal axis and transverse wave impedance as the vertical axis to obtain multiple template lines.

[0044] To determine multiple mud content values, the mud content may be fixed between 0 and 1, and multiple mud content values ​​may be determined at set intervals (which may be flexibly set according to research needs), wherein the largest of the determined mud content values ​​is 1 and the smallest is 0. Figure 2 As shown in the figure, the mud content V sh The template lines corresponding to 0.00, 0.20, 0.40, 0.60, 0.80 and 1.00 (from bottom to top, the mud content corresponding to the template lines increases successively). It can be seen that the template lines are parallel to each other, and the form is: Y = G·X + P j , which is G·X-Y+P j =0, where X is the longitudinal wave impedance I P , Y is the shear wave impedance I S , G is the slope, P j is the intercept of each template line.

[0045] The distance between any two template lines is determined by the following formula (6):

[0046]

[0047] In formula (6), D T is the standard distance between template line 11 and template line 22, P 11 and P 22 They are the intercepts of template line 11 and template line 22 respectively.

[0048] It is found through calculation that the ratio between the distance between any two template lines and the absolute value of the corresponding difference in mud content is a certain value. Therefore, two template lines can be selected as standards, the distance between the two and the corresponding difference in mud content can be calculated in advance, and then the mud content of the point to be estimated can be determined by the distance between the point to be estimated and one of the template lines.

[0049] Based on the understanding of the above rules, in subsequent practical applications, it is not necessary to establish too many template lines, but only two standard template lines. That is:

[0050] On the basis of step S11 and step S12, a first character sample set with a first set mud content and a second character sample set with a second set mud content are extracted from the third sample set, and the extracted first character sample set and the second character sample set are projected into the coordinate system to obtain a first template line corresponding to the first sub-sample set and a second template line corresponding to the second sub-sample set.

[0051] For the convenience of calculation, template lines corresponding to shale contents of 0 and 1 are usually established. Otherwise, the relationship between the shale content of the estimated point and the shale content corresponding to the standard template line must be determined. Furthermore, it is determined whether the estimated point is above or below the standard template line. If it is above, the shale content of the estimated point is greater than the shale content corresponding to the standard template line; if it is below, the shale content of the estimated point is less than the shale content corresponding to the standard template line. By determining the standard template line (i.e., the first template line) as a template line with a shale content of 0, the step of judging the relationship between the shale content of the estimated point and the shale content corresponding to the standard template line can be omitted, because the shale content is definitely greater than or equal to 0.

[0052] The distance in the embodiment of the present invention refers to the vertical distance. Furthermore, the distance between two template lines refers to the vertical distance between the two template lines; the distance from the point to be estimated to the template line refers to the length of the vertical line segment obtained by drawing a perpendicular line from the point to be estimated to the template line. The distance here is not the traditional distance in space or time, but the distance in the extended sense, which is the distance in the longitudinal wave impedance and transverse wave impedance domain.

[0053] Embodiment 2

[0054] Embodiment 2 of the present invention provides a method for determining shale content based on seismic elastic parameters, and its process is as follows: Figure 3 As shown, the following steps are included:

[0055] Step S31: Determine the distance between the point to be estimated and the first template line in the two-dimensional coordinate system of the longitudinal and transverse wave impedances according to the longitudinal and transverse wave impedances of the point to be estimated.

[0056] The distance between the point to be estimated and the first template line in the two-dimensional coordinate system of longitudinal and transverse wave impedance is determined by the following formula (7):

[0057]

[0058] In formula (7), D i is the distance between the point to be estimated with sequence number i and the first template line, I pi and I si are the longitudinal wave impedance and transverse wave impedance of the point to be estimated, G is the slope of the template line in the coordinate system (the slopes of each template line are equal), and P1 is the intercept of the first template line.

[0059] Step S32: According to the distance, the standard distance between the first template line and the second template line, and the difference between the mud content corresponding to the first template line and the mud content corresponding to the second template line, the mud content of the point to be estimated is determined in a proportional manner.

[0060] The first template line and the second template line are two parallel straight lines in the coordinate system, the mud content of each point on the first template line is the same, and the mud content of each point on the second template line is the same.

[0061] The standard distance between the first template line and the second template line is predetermined by the following formula (8):

[0062]

[0063] In formula (8), D s is the standard distance between the first template line and the second template line, G is the slope of the template line in the coordinate system, and P1 and P2 are the intercepts of the first template line and the second template line, respectively.

[0064] When the shale content of each point on the first template line is 0 and the shale content of each point on the second template line is 1, the shale content V of the point to be estimated is determined by the following formula (9): shi :

[0065]

[0066] In formula (9), D i is the distance between the point to be estimated with serial number i and the first template line, D sis the standard distance between the first template line and the second template line.

[0067] Previous quantitative prediction methods for mud content either have low accuracy, while high-precision methods are often difficult to apply on a large scale. The mud content determination method based on seismic elastic parameters provided in this embodiment obtains a first sample set and a second sample set under the calibration of known well or core data, establishes a rock physics model that characterizes the relationship between mud content, porosity, and longitudinal and transverse wave velocities, and then establishes a seismic elastic parameter interpretation template line for mud content interpretation, and calculates the mud content by solving the distance between the estimated point and the template line. This method combines experimental data to construct a rock physics model, and on this basis, a relatively simple mathematical relationship can be used to achieve quantitative calculation of mud content, which is more suitable for industrial promotion and application.

[0068] The above-mentioned method for determining the shale content based on seismic elastic parameters is used to calculate the shale content. The calculation effect diagram is shown in Figure 4 , we can see that the verification well and the measured mud content have a good match, indicating that it has a high accuracy.

[0069] Based on the inventive concept of the present invention, an embodiment of the present invention further provides a device for determining the shale content based on seismic elastic parameters. The structure of the device is as follows: Figure 5 As shown, including:

[0070] A distance determination module 51 is used to determine the distance between the point to be estimated and the first template line in the two-dimensional coordinate system of longitudinal and transverse wave impedances according to the longitudinal and transverse wave impedances of the point to be estimated;

[0071] The mud content determination module 52 is used to determine the mud content of the point to be estimated in a proportional manner according to the distance, the standard distance between the first template line and the second template line, and the difference between the mud content corresponding to the first template line and the mud content corresponding to the second template line, wherein the first template line and the second template line are two parallel straight lines in the coordinate system, the mud content of each point on the first template line is the same, and the mud content of each point on the second template line is the same.

[0072] In some embodiments, the distance determination module 51 determines the distance between the point to be estimated and the first template line in the two-dimensional coordinate system of longitudinal and transverse wave impedances, for:

[0073] The distance between the point to be estimated and the first template line in the two-dimensional coordinate system of longitudinal and transverse wave impedance is determined by the following formula:

[0074]

[0075] Among them, D i is the distance between the point to be estimated with sequence number i and the first template line, I pi and ISi are respectively the longitudinal wave impedance and the transverse wave impedance of the point to be estimated, G is the slope of the template line in the coordinate system, and P1 is the intercept of the first template line.

[0076] In some embodiments, the mud content determination module 52 determines the mud content of the estimated point in a manner that the distance is proportional to the mud content difference, and is used to:

[0077] The mud content V of the estimated point is determined by the following formula shi :

[0078]

[0079] Where D i is the distance between the point to be estimated with serial number i and the first template line, D s is the standard distance between the first template line and the second template line.

[0080] In some embodiments, the above device further comprises a template line establishing module 53, which is used to pre-establish the first template line and the second template line in the following manner:

[0081] Based on the first sample set, a rock physics model characterizing the relationship between mud content, porosity and P-wave and S-wave velocities is established by multivariate linear regression, wherein each sample of the first sample set includes mud content, porosity, P-wave velocity and S-wave velocity at the same position; based on the second sample set, a third sample set is obtained by using the conversion relationship between P-wave and S-wave velocities and P-wave and S-wave impedances and the rock physics model, wherein each sample of the second sample set includes mud content and porosity at the same position, and each sample of the third sample set includes mud content, porosity, P-wave impedance and S-wave impedance at the same position; a first sub-sample set with a mud content of a first set value and a second sub-sample set with a mud content of a second set value are extracted from the third sample set, and the extracted first sub-sample set and the second sub-sample set are projected into the coordinate system to obtain a first template line corresponding to the first sub-sample set and a second template line corresponding to the second sub-sample set.

[0082] In some embodiments, the template line establishment module 53, based on the first sample set, establishes a rock physics model that characterizes the relationship between shale content, porosity and P- and S-wave velocities through multivariate linear regression, for:

[0083] Based on the first sample set, a rock physics model characterizing the relationship between shale content, porosity and P- and S-wave velocities was established by multivariate linear regression as follows:

[0084] V P =AB·φ-C·V sh

[0085] VS =DE·φ-F·V sh

[0086] Among them, V P is the longitudinal wave velocity, V S is the shear wave velocity, φ is the porosity, V sh is the mud content, A, B, C, D, E and F are fitting constants.

[0087] In some embodiments, the template line establishment module 53 uses the conversion relationship between P-wave velocity and P-wave impedance and the rock physics model to obtain a third sample set, which is used to:

[0088] Using the rock physics model, the third sample set is obtained by the following formula:

[0089] I P =V P ·ρ

[0090] I S =V S ·ρ

[0091] ρ=ρ ma *(1-V sh -φ)+ρ sh *V sh +ρ f *φ

[0092] Among them, ρ ma , sh and ρ f are the known densities of pure sandstone, pure mudstone and fluid, ρ is the reservoir density, I S is the shear wave impedance, I P is the longitudinal wave impedance.

[0093] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0094] Based on the inventive concept of the present invention, an embodiment of the present invention further provides a computer storage medium, wherein the computer storage medium stores computer executable instructions, and when the computer executable instructions are executed by a processor, the above-mentioned method for determining mud content based on seismic elastic parameters is implemented.

[0095] Based on the inventive concept of the present invention, an embodiment of the present invention also provides a server, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the above-mentioned method for determining mud content based on seismic elastic parameters is implemented.

[0096] Unless otherwise specifically stated, terms such as processing, computing, calculating, determining, displaying, etc. may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, which operate and convert data represented as physical (e.g., electronic) quantities within registers or memories of a processing system into other data similarly represented as physical quantities within memories, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0097] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0098] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that an embodiment of the claimed subject matter requires more features than those set forth in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0099] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0100] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0101] For software implementation, the techniques described in this application can be implemented with modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0102] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to represent "non-exclusive or". The terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.

Claims

1. A method for determining shale content based on seismic elastic parameters, characterized in that: include: Determine the distance between the point to be estimated and the first template line in the two-dimensional coordinate system of the longitudinal and transverse wave impedances according to the longitudinal and transverse wave impedances of the point to be estimated; According to the distance, the standard distance between the first template line and the second template line, and the difference between the mud content corresponding to the first template line and the mud content corresponding to the second template line, the mud content of the point to be estimated is determined in a manner that the distance is proportional to the mud content difference, wherein the first template line and the second template line are two parallel straight lines in the coordinate system, the mud content of each point on the first template line is the same, and the mud content of each point on the second template line is the same.

2. The method according to claim 1, characterized in that The coordinate system has the longitudinal wave impedance as the horizontal axis and the transverse wave impedance as the vertical axis.

3. The method according to claim 2, characterized in that Determining the distance between the point to be estimated and the first template line in the two-dimensional coordinate system of longitudinal and transverse wave impedances includes: The distance between the point to be estimated and the first template line in the two-dimensional coordinate system of longitudinal and transverse wave impedance is determined by the following formula (1): In formula (1), D i is the distance between the point to be estimated with sequence number i and the first template line, I pi and I si are respectively the longitudinal wave impedance and the transverse wave impedance of the point to be estimated, G is the slope of the template line in the coordinate system, and P1 is the intercept of the first template line.

4. The method according to claim 2, characterized in that: The standard distance between the first template line and the second template line is predetermined by the following formula (2): In formula (2), D s is the standard distance between the first template line and the second template line, G is the slope of the template line in the coordinate system, and P1 and P2 are the intercept of the first template line and the intercept of the second template line, respectively.

5. The method according to claim 1, characterized in that The shale content of each point on the first template line is 0, and the shale content of each point on the second template line is 1.

6. The method according to claim 5, characterized in that The method of determining the mud content of the point to be estimated by a method in which the distance is proportional to the mud content difference includes: The mud content V of the estimated point is determined by the following formula (3): shi : In formula (3), D i is the distance between the point to be estimated with serial number i and the first template line, D s is the standard distance between the first template line and the second template line.

7. The method according to claim 1, characterized in that The first template line and the second template line are pre-established in the following manner: Based on the first sample set, a rock physics model characterizing the relationship between shale content, porosity and P-wave velocity and S-wave velocity is established by multivariate linear regression, wherein each sample of the first sample set includes shale content, porosity, P-wave velocity and S-wave velocity at the same location; Based on the second sample set, a third sample set is obtained by using the conversion relationship between P-wave velocity and P-wave impedance and the rock physics model, wherein each sample of the second sample set includes the shale content and porosity at the same location, and each sample of the third sample set includes the shale content, porosity, P-wave impedance and P-wave impedance at the same location; A first character sample set with a first set mud content and a second character sample set with a second set mud content are extracted from the third sample set, and the extracted first character sample set and the second character sample set are projected into the coordinate system to obtain a first template line corresponding to the first sub-sample set and a second template line corresponding to the second sub-sample set.

8. The method according to claim 7, characterized in that The rock physics model characterizing the relationship between shale content, porosity and P- and S-wave velocities is established based on the first sample set through multiple linear regression, including: Based on the first sample set, a rock physics model characterizing the relationship between shale content, porosity and P- and S-wave velocities was established by multivariate linear regression as follows: IN P =AB·φ-C·V sh (4) V S =D-E·φ-F·V sh (5) In formulas (4) and (5), V P is the longitudinal wave velocity, V S is the shear wave velocity, φ is the porosity, V sh is the mud content, A, B, C, D, E and F are fitting constants.

9. The method according to claim 8, characterized in that The third sample set is obtained by using the conversion relationship between P-wave velocity and P-wave impedance and the rock physics model, including: Using the rock physics model, the third sample set is obtained through the following equations (6)-(8): I P =V P ·r (6) I S =V S ·r (7) p=p ma *(1-V sh -φ)+ρ sh *V sh +r f *φ (8) In formulas (6)-(8), ρ ma , sh and ρ f are the known densities of pure sandstone, pure mudstone and fluid, ρ is the reservoir density, I S is the shear wave impedance, I P is the longitudinal wave impedance.

10. A device for determining shale content based on seismic elastic parameters, characterized in that: The device comprises: A distance determination module, used to determine the distance between the point to be estimated and the first template line in the two-dimensional coordinate system of longitudinal and transverse wave impedances according to the longitudinal and transverse wave impedances of the point to be estimated; A mud content determination module is used to determine the mud content of the point to be estimated in a proportional manner according to the distance, the standard distance between the first template line and the second template line, and the difference between the mud content corresponding to the first template line and the mud content corresponding to the second template line, wherein the first template line and the second template line are two parallel straight lines in the coordinate system, the mud content of each point on the first template line is the same, and the mud content of each point on the second template line is the same.

11. A computer storage medium, characterized in that: The computer storage medium stores computer executable instructions, and when the computer executable instructions are executed by a processor, the method for determining shale content based on seismic elastic parameters according to any one of claims 1 to 9 is implemented.

12. A server, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for determining the shale content based on seismic elastic parameters according to any one of claims 1 to 9 is implemented.

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