Fluid and pressure decoupling method and device in time-lapse earthquake, electronic equipment and storage medium

Abstract

The invention discloses a fluid and pressure decoupling method and device in a time-lapse earthquake, electronic equipment and a storage medium. The method comprises the following steps: determining a longitudinal wave impedance difference body and a transverse wave impedance difference body of a research target region based on time-lapse seismic data of the research target region; substituting the longitudinal wave impedance difference body and the transverse wave impedance difference body into a first transformation formula to obtain a fluid saturation change attribute body, wherein the first transformation formula is a linear function between the first data and the target impedance difference value; substituting the longitudinal wave impedance difference body and the transverse wave impedance difference body into a second transformation formula to obtain a pore pressure change attribute body, wherein the second transformation formula is a linear function between second data and a target impedance difference value; and based on the fluid saturation change attribute body and the pore pressure change attribute body, identifying signals of fluid saturation change and pore pressure change of the research target region in the time-lapse earthquake. According to the scheme, effective decoupling separation of fluid and pressure signals of the target region in time-lapse earthquake can be realized.

Description

Technical Field

[0001] This invention relates to the field of oil and gas geophysical exploration technology, and in particular to a method, apparatus, electronic device and storage medium for decoupling fluid and pressure in time-lapse earthquakes. Background Technology

[0002] In the development and production process of oil fields, time-shift seismic technology, also known as four-dimensional seismic technology, is often used. By analyzing the baseline and monitoring the changes in the seismic response between two acquisitions, it is possible to infer the changes in the underground oil reservoir after extraction and fluid injection, and guide the optimization of the injection-production well network to improve the oil field recovery rate.

[0003] In actual injection and production processes, changes in reservoir fluid saturation and pore pressure both lead to variations in elastic parameters, which in turn cause changes in seismic amplitude. This makes it impossible to distinguish between changes in fluid saturation and pore pressure when directly observing amplitude data. Furthermore, as oilfield development progresses and the scope of the injection and production impact expands, the complex interference between changes in fluid saturation and pore pressure necessitates effective decoupling and separation of fluid and pressure signals during time-lapsed seismic events. Summary of the Invention

[0004] This invention provides a method, apparatus, electronic device, and storage medium for decoupling fluid and pressure in time-lapse earthquakes, so as to achieve decoupling and separation of fluid and pore pressure in oil fields during time-lapse earthquakes.

[0005] According to one aspect of the present invention, a method for decoupling fluid and pressure in time-shifted earthquakes is provided, the method comprising:

[0006] Based on time-shifted seismic data of the target area, the P-wave impedance difference volume and S-wave impedance difference volume of the target area were determined.

[0007] Substituting the longitudinal wave impedance difference volume and the transverse wave impedance difference volume into the first transformation formula yields the fluid saturation change attribute volume. The first transformation formula is a linear function between the first data and the target impedance difference. The first transformation formula is determined based on a reference well, which is a drilled well with complete geological parameter curve data and elastic parameter curve data in the target area. The first data is used to indicate the change in fluid saturation. The target impedance difference includes the longitudinal wave impedance difference and the transverse wave impedance difference.

[0008] Substituting the longitudinal wave impedance difference volume and the transverse wave impedance difference volume into the second transformation formula yields the pore pressure change attribute volume. The second transformation formula is a linear function between the second data and the target impedance difference. The second transformation formula is determined based on the reference well. The second data is used to indicate the change in pore pressure.

[0009] The signals of fluid saturation change and pore pressure change in the target area during time-lapse earthquakes are identified based on the fluid saturation change attribute volume and pore pressure change attribute volume.

[0010] According to another aspect of the present invention, a fluid and pressure decoupling device for time-shifted earthquakes is provided, the device comprising:

[0011] The first determination module is used to determine the P-wave impedance difference volume and the S-wave impedance difference volume of the research target area based on the time-shifted seismic data of the research target area.

[0012] The first acquisition module is used to substitute the longitudinal wave impedance difference volume and the transverse wave impedance difference volume into the first transformation formula to obtain the fluid saturation change attribute volume. The first transformation formula is a linear function between the first data and the target impedance difference. The first transformation formula is determined based on the reference well. The reference well is a drilled well with complete geological parameter curve data and elastic parameter curve data in the target area. The first data is used to indicate the change of fluid saturation. The target impedance difference includes the longitudinal wave impedance difference and the transverse wave impedance difference.

[0013] The second acquisition module is used to substitute the longitudinal wave impedance difference body and the transverse wave impedance difference body into the second transformation formula to obtain the pore pressure change attribute body. The second transformation formula is a linear function between the second data and the target impedance difference. The second transformation formula is determined based on the reference well. The second data is used to indicate the change of pore pressure.

[0014] The identification module is used to identify signals of fluid saturation changes and pore pressure changes in the target area during time-lapse earthquakes based on fluid saturation change attribute volume and pore pressure change attribute volume.

[0015] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0016] At least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the fluid and pressure decoupling method in time-shifted earthquakes according to any embodiment of the present invention.

[0017] According to another aspect of the present invention, a computer-readable storage medium is provided storing computer instructions for causing a processor to execute and implement the fluid and pressure decoupling method in time-shifted earthquakes according to any embodiment of the present invention.

[0018] The technical solution of this invention determines the P-wave impedance difference volume and S-wave impedance difference volume of the research target area based on time-lapsed seismic data of the research target area; substitutes the P-wave impedance difference volume and S-wave impedance difference volume into a first transformation formula to obtain a fluid saturation change attribute volume, where the first transformation formula is a linear function between the first data and the target impedance difference; substitutes the P-wave impedance difference volume and S-wave impedance difference volume into a second transformation formula to obtain a pore pressure change attribute volume, where the second transformation formula is a linear function between the second data and the target impedance difference; and identifies the signals of fluid saturation change and pore pressure change in the research target area during time-lapsed seismic events based on the fluid saturation change attribute volume and the pore pressure change attribute volume, thereby effectively decoupling the fluid and pressure signals by describing the changes in fluid saturation and pore pressure in the research target area during time-lapsed seismic events.

[0019] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A flowchart illustrating a fluid and pressure decoupling method in time-shifted earthquakes provided by an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of a target difference data volume provided in an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of a longitudinal wave impedance difference body provided in an embodiment of the present invention;

[0024] Figure 4 A schematic diagram of a transverse wave impedance difference body provided in an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of a fluid saturation variation property body provided in an embodiment of the present invention;

[0026] Figure 6 This is a schematic diagram of a pore pressure variation property body provided in an embodiment of the present invention;

[0027] Figure 7 A schematic diagram of seismic forward modeling under single-factor variations of fluid saturation and pore pressure, provided as an embodiment of the present invention;

[0028] Figure 8 A time-shifted seismic amplitude difference planar diagram provided in an embodiment of the present invention;

[0029] Figure 9 A fluid saturation variation property plane diagram provided in an embodiment of the present invention;

[0030] Figure 10 A pore pressure variation property planar diagram provided for an embodiment of the present invention;

[0031] Figure 11 A dynamic monitoring data diagram of water injection wells and gas injection wells provided in an embodiment of the present invention;

[0032] Figure 12 A flowchart illustrating another method for decoupling fluid and pressure in time-shifted earthquakes provided in this embodiment of the invention;

[0033] Figure 13 A schematic diagram of a reference geological parameter curve and a reference elastic parameter curve provided for an embodiment of the present invention;

[0034] Figure 14 This is a schematic diagram illustrating the variation trend of fluid and pressure in the intersection region of longitudinal wave impedance and transverse wave impedance when the lithology and physical properties are homogeneous, as provided in an embodiment of the present invention.

[0035] Figure 15 This is a schematic diagram illustrating linear fitting of impedance pairs based on the fluid saturation associated with impedance pairs to a target number, as provided in an embodiment of the present invention.

[0036] Figure 16 This is a schematic diagram illustrating linear fitting of impedance pairs based on the pore pressure as a target number, provided as an embodiment of the present invention.

[0037] Figure 17 A schematic diagram of a fluid and pressure decoupling device in time-shifted earthquakes provided in an embodiment of the present invention;

[0038] Figure 18 This is a schematic diagram of an electronic device for implementing a fluid and pressure decoupling method in time-shifted earthquakes, as provided in an embodiment of the present invention. Detailed Implementation

[0039] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0040] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0041] Figure 1 This is a flowchart illustrating a fluid and pressure decoupling method in time-lapse earthquakes provided by an embodiment of the present invention. This embodiment is applicable to situations requiring the decoupling and separation of fluid saturation and pore pressure in a target area during time-lapse earthquakes. This method can be executed by a fluid and pressure decoupling device in time-lapse earthquakes, which can be implemented in hardware and / or software and configured in an electronic device implementing the fluid and pressure decoupling method in time-lapse earthquakes. Figure 1 As shown, the fluid and pressure decoupling method in this time-lapse earthquake includes:

[0042] S101. Based on the time-shifted seismic data of the target area, determine the P-wave impedance difference volume and S-wave impedance difference volume of the target area.

[0043] Time-shifted seismic surveys refer to dynamic monitoring that incorporates a time dimension into 3D seismic exploration. Time-shifted seismic data includes 3D seismic data acquired at the baseline time and 3D seismic data acquired at the monitoring time, with the baseline time preceding the monitoring time. By comparing and analyzing the 3D seismic data acquired at the baseline time and the 3D seismic data acquired at the monitoring time, the changes in the physical properties of the subsurface reservoirs in the study area between the baseline time and the monitoring time can be determined. Water injection, gas injection, and oil and gas extraction may occur in the study area during time-shifted seismic surveys.

[0044] The longitudinal wave impedance difference volume refers to the data volume consisting of the longitudinal wave impedance at the monitoring time minus the longitudinal wave impedance at the baseline time, obtained by subtracting the longitudinal wave impedance at the monitoring time from the longitudinal wave impedance at the baseline time. The transverse wave impedance difference volume refers to the data volume consisting of the transverse wave impedance at the monitoring time minus the transverse wave impedance at the baseline time, obtained by subtracting the transverse wave impedance at the monitoring time from the transverse wave impedance at the baseline time. Both the longitudinal wave impedance difference volume and the transverse wave impedance difference volume have the same dimensions and size.

[0045] As an optional implementation of this invention, determining the P-wave impedance difference volume and S-wave impedance difference volume of the research target area based on time-shifted seismic data of the research target area includes: determining time-shifted seismic difference data based on monitoring data and baseline data of time-shifted seismic data of the research target area, and determining at least three target difference data volumes based on the time-shifted seismic difference data, wherein the target difference data volumes are obtained by angular superposition of the time-shifted seismic difference data within a preset seismic wave incident angle range; and determining the P-wave impedance difference volume and S-wave impedance difference volume by performing time-shifted seismic pre-stack inversion based on the at least three target difference data volumes.

[0046] The seismic wave incident angle can refer to the angle between the direction of seismic wave propagation and the normal to the reflecting interface. The preset range of seismic wave incident angles can be defined based on the differences in the sensitivity of reflected signals at different incident angles to reservoir elastic parameters. For example, the preset range of seismic wave incident angles can be 0°–15°, 15°–30°, or 30°–45°. Time-shifted seismic difference data can refer to the difference between 3D seismic data acquired at the monitoring time and 3D seismic data acquired at the baseline time, which is included in the time-shifted seismic data. Pre-stack inversion of time-shifted seismic data can refer to the technique of performing pre-stack inversion based on time-shifted seismic data.

[0047] Specifically, for each of the at least three preset seismic wave incident angle ranges, at least three target difference data volumes are obtained by angularly superimposing the pre-stack incident angle gathers of time-lapsed seismic difference data of the target area within the preset seismic wave incident angle range. Then, based on the at least three target difference data volumes, time-lapsed pre-stack seismic inversion is performed to determine the P-wave impedance difference volume and S-wave impedance difference volume of the target area, ensuring the accuracy of the P-wave impedance difference volume and S-wave impedance difference volume. For example, based on... Figure 2 The three target difference data volumes shown are obtained by superimposing angles within preset seismic wave incident angle ranges of 4°–15° (corresponding to near angle), 15°–26° (corresponding to intermediate angle), and 26°–37° (corresponding to far angle), respectively. This allows us to determine... Figure 3 The longitudinal wave impedance difference body shown and Figure 4 The transverse wave impedance difference body is shown.

[0048] S102. Substitute the longitudinal wave impedance difference volume and the transverse wave impedance difference volume into the first transformation formula to obtain the fluid saturation change attribute volume. The first transformation formula is a linear function between the first data and the target impedance difference. The first transformation formula is determined based on the reference well. The reference well is a drilled well with complete geological parameter curve data and elastic parameter curve data in the target area. The first data is used to indicate the change of fluid saturation. The target impedance difference includes the longitudinal wave impedance difference and the transverse wave impedance difference.

[0049] The output of the first transformation formula is the first data. The first transformation formula is determined based on a reference well, and represents the relationship between the fluid saturation change and the target impedance difference in the target area as determined by the fluid saturation change from the reference well. For example, the first transformation formula can be expressed as F1(ΔZp, ΔZs), where ΔZp represents the longitudinal wave impedance difference and ΔZs represents the transverse wave impedance difference.

[0050] Specifically, for each longitudinal wave impedance difference in the longitudinal wave impedance difference body and each transverse wave impedance difference in the transverse wave impedance difference body, the longitudinal wave impedance difference and transverse wave impedance difference at the same location are used as the target impedance differences corresponding to the longitudinal wave impedance difference body and the transverse wave impedance difference body, respectively. Furthermore, by sequentially substituting the target impedance differences corresponding to the longitudinal wave impedance difference body and the transverse wave impedance difference body into the first transformation formula, the first data corresponding to the longitudinal wave impedance difference body and the transverse wave impedance difference body can be obtained, thereby forming a fluid saturation change attribute body using the first data corresponding to the longitudinal wave impedance difference body and the transverse wave impedance difference body. The fluid saturation change attribute body and the longitudinal wave impedance difference body have the same dimension and size. For example, [the following is an example of a process where...] Figure 3 The longitudinal wave impedance difference body shown and Figure 4 Substituting the transverse wave impedance difference shown into the first transformation equation yields... Figure 5 The fluid saturation change property is shown.

[0051] S103. Substitute the longitudinal wave impedance difference volume and the transverse wave impedance difference volume into the second transformation formula to obtain the pore pressure change attribute volume. The second transformation formula is a linear function between the second data and the target impedance difference. The second transformation formula is determined based on the reference well. The second data is used to indicate the change of pore pressure.

[0052] The output of the second transformation formula is the second data. The second transformation formula is determined based on a reference well, and represents the relationship between the pore pressure change and the target impedance difference in the target area as determined by the pore pressure change from the reference well. For example, the second transformation formula can be expressed as F2(ΔZp,ΔZs).

[0053] Specifically, by sequentially substituting the target impedance differences corresponding to the longitudinal wave impedance difference body and the transverse wave impedance difference body into the second transformation formula, the second data corresponding to the longitudinal wave impedance difference body and the transverse wave impedance difference body can be obtained. Thus, a pore pressure variation attribute body is formed using the second data corresponding to the longitudinal wave impedance difference body and the transverse wave impedance difference body. The pore pressure variation attribute body and the longitudinal wave impedance difference body have the same dimension and size. For example, [the following is an example of...] Figure 3 The longitudinal wave impedance difference body shown and Figure 4 Substituting the transverse wave impedance difference shown into the second transformation equation yields... Figure 6 The pore pressure variation property is shown.

[0054] S104. Based on the fluid saturation change attribute volume and pore pressure change attribute volume, identify the signals of fluid saturation change and pore pressure change in the target area during time-lapse earthquakes.

[0055] Specifically, the fluid saturation change attribute can describe the changes in fluid saturation in the target area during time-lapse earthquake simulations, while the pore pressure change attribute can describe the changes in pore pressure in the target area during time-lapse earthquake simulations. Furthermore, by studying the changes in fluid saturation and pore pressure in the target area during time-lapse earthquake simulations, effective decoupling of the fluid saturation change signal and the pore pressure change signal can be achieved.

[0056] As an optional embodiment of the present invention, the signals of fluid saturation change and pore pressure change in the research target area during time-lapsed earthquakes are identified based on the fluid saturation change attribute volume and the pore pressure change attribute volume. This includes: determining a fluid saturation change attribute plane map corresponding to the research target area based on the fluid saturation change attribute volume, and determining the intensity and range of fluid saturation change in the research target area from the baseline to the monitoring earthquake acquisition based on the fluid saturation change attribute plane map; determining a pore pressure change attribute plane map corresponding to the research target area based on the pore pressure change attribute volume, and determining the intensity and range of pore pressure change in the research target area from the baseline to the monitoring earthquake acquisition based on the pore pressure change attribute plane map.

[0057] Specifically, the fluid saturation change attribute volume can be used to describe the changes in fluid saturation in the target area during time-lapse seismic acquisition. Therefore, the fluid saturation change attribute plane map determined based on the fluid saturation change attribute volume can be used to accurately describe the intensity and extent of fluid saturation changes in the target area from the baseline to the monitoring seismic acquisition. Similarly, the pore pressure change attribute volume can be used to describe the changes in pore pressure in the target area during time-lapse seismic acquisition. Therefore, the pore pressure change attribute plane map determined based on the pore pressure change attribute volume can be used to accurately describe the intensity and extent of pore pressure changes in the target area from the baseline to the monitoring seismic acquisition.

[0058] For example, refer to Figure 7 Changes in fluid saturation and pore pressure can be misrepresented in seismic amplitude changes: the amplitude changes of rising water saturation and falling pore pressure are similar, as are the amplitude changes of rising gas saturation and rising pore pressure. Since the amplitude changes caused by rising water saturation and rising pore pressure are opposite, when they occur at the same spatial location, they cancel each other out, creating a time-shifted seismic difference dark area. Similarly, rising gas saturation and falling pore pressure at the same spatial location also create a time-shifted seismic difference dark area. The existence of such dark areas can lead to them being misinterpreted as areas of weak fluid or pressure change. Therefore, it is difficult to effectively distinguish fluid and pressure signals directly from time-shifted amplitude difference data. For example, Figure 8 The time-lapse seismic amplitude difference planar map shown indicates that within the vicinity of injection well A in the target area (i.e., within the yellow dashed line), there is a dark area of ​​time-lapse seismic amplitude difference. A large area of ​​negative response to time-lapse seismic amplitude difference exists between the yellow and white dashed lines. Therefore, it is difficult to accurately interpret the intensity and spread of fluid and pressure directly from the time-lapse seismic amplitude difference data. Furthermore, Figure 9 The fluid saturation change property plane diagram shows that the area within the yellow dashed line represents the water injection sweep response caused by injection well A; Figure 10 The white dashed line area in the pore pressure change property diagram shows the pressure rise wave and response caused by injection well A, indicating a wider pressure transmission range; (Comparison) Figure 11 The dynamic monitoring data of injection well A shown in the figure shows that the pore pressure monitoring curve of injection well A increases significantly from the baseline time to the monitoring time, and the decoupling effect is verified in the injection well. Figure 8 Near the gas injection well B, within the green dashed line, a negative response due to time-shifted seismic amplitude difference appears, similar to the large negative response within the white dashed line. It is difficult to distinguish whether the negative response within the green dashed line is caused by gas injection or pressurization based on the time-shifted seismic amplitude difference. Figure 9 Near gas injection well B, the area within the green dashed line shows the gas injection response. Figure 10 The green dashed line represents the weak voltage transformer response. (See reference line.) Figure 11 The dynamic monitoring data of injection well B shown indicates that the pressure of injection well B did not change significantly from the baseline time to the monitoring time, and the decoupling effect was also verified in injection well B.

[0059] The technical solution of this invention determines the P-wave impedance difference volume and S-wave impedance difference volume of the research target area based on time-lapsed seismic data of the research target area; substitutes the P-wave impedance difference volume and S-wave impedance difference volume into a first transformation formula to obtain a fluid saturation change attribute volume, where the first transformation formula is a linear function between the first data and the target impedance difference; substitutes the P-wave impedance difference volume and S-wave impedance difference volume into a second transformation formula to obtain a pore pressure change attribute volume, where the second transformation formula is a linear function between the second data and the target impedance difference; and identifies the signals of fluid saturation change and pore pressure change in the research target area during time-lapsed seismic events based on the fluid saturation change attribute volume and the pore pressure change attribute volume, thereby effectively decoupling the fluid and pressure signals by describing the changes in fluid saturation and pore pressure in the research target area during time-lapsed seismic events.

[0060] Figure 12 A flowchart illustrating another method for decoupling fluid and pressure in time-shifted earthquakes provided by an embodiment of the present invention. Figure 12 As shown, the fluid and pressure decoupling method in this time-lapse earthquake includes:

[0061] S201. Determine the reference geological parameter curves for the reference well. The reference geological parameter curves include: mineral proportion curve, porosity curve, overburden pressure curve, fluid saturation curve, and pore pressure curve.

[0062] Among these, the geological parameter curve can refer to a curve used to describe the variation of geological parameters with depth. The reference geological parameter curve can be obtained by calculation based on a reference well.

[0063] S202. The target geological parameter curve is obtained by modifying the fluid saturation curve and / or pore pressure curve in the reference geological parameter curve.

[0064] Modifying the fluid saturation curve can refer to adjusting the saturation levels of each fluid element in the curve to a preset saturation level. Similarly, modifying the pore pressure curve can refer to changing the pore pressure levels to a preset pressure. The upper limit of the preset pressure does not exceed the overlying pressure of the reservoir section, ensuring the effective pressure remains positive. Different target geological parameter curves can be obtained by making different modifications to only the fluid saturation curve, pore pressure curve, or both of the fluid saturation curve and pore pressure curve in the reference geological parameter curves.

[0065] S203. Based on the target geological parameter curve, rock physics forward modeling is performed to obtain the target elastic parameter curve, which includes the longitudinal wave impedance curve and the transverse wave impedance curve.

[0066] Here, the elastic parameter curve refers to a curve describing how elastic parameters change with depth. Rock physics forward modeling refers to the process of quantitatively calculating the elastic parameter curve based on the geological parameter curve using a rock physics model. The target geological parameter curve and the target elastic parameter curve correspond to the same depth range. Elastic parameters can be determined based on mineral proportion, porosity, fluid saturation, and effective pressure, while effective pressure can be determined based on overlying pressure and pore pressure.

[0067] As an optional embodiment of the present invention, obtaining the target elastic parameter curve by rock physics forward modeling based on the target geological parameter curve includes: adjusting the theoretical rock physics model based on the reference geological parameter curve and the reference elastic parameter curve until the elastic parameter curve obtained by the rock physics forward modeling based on the reference geological parameter curve matches the reference elastic parameter curve; then using the adjusted theoretical rock physics model as the target area rock physics model; the reference elastic parameter curve includes the density curve, the P-wave impedance curve, and the S-wave impedance curve; and obtaining the target elastic parameter curve by rock physics forward modeling based on the target geological parameter curve using the target area rock physics model.

[0068] In this context, a theoretical rock physics model refers to a mathematical model that describes the quantitative relationship between rock elastic parameters and geological parameters based on fundamental theories of physics, mechanics, and geology. Elastic parameter curves can be generated by inputting geological parameter curves into the theoretical rock physics model. For example, the theoretical rock physics model can be a theoretical model for pressure-dependent loosely cemented sandstone. Reference elastic parameter curves can be obtained through field measurements based on reference wells.

[0069] Specifically, the elastic parameter curves obtained by forward modeling rock physics using theoretical rock physics models based on reference geological parameter curves can be used as predicted elastic parameter curves. Furthermore, the reference... Figure 13 The theoretical rock physics model is adjusted by comparing the predicted elastic parameter curves with the reference elastic parameter curves until they match perfectly. The adjusted model can then be used as the target area rock physics model. By performing forward modeling of the target area rock physics model based on the target geological parameter curves to obtain the target elastic parameter curves, the accuracy of the target elastic parameter curves can be improved.

[0070] S204. Determine the first transformation formula and the second transformation formula based on the target geological parameter curve and the target elastic parameter curve.

[0071] Specifically, the first transformation formula can be determined based on the fluid saturation curve and the target elastic parameter curve in the target geological parameter curve, and the second transformation formula can be determined based on the pore pressure curve and the target elastic parameter curve in the target geological parameter curve, so as to improve the accuracy of the first transformation formula and the second transformation formula.

[0072] As an optional embodiment of the present invention, determining the first transformation formula and the second transformation formula based on the target geological parameter curve and the target elastic parameter curve includes the following steps A1-A3:

[0073] Step A1: Determine the target number of impedance pairs based on the target elastic parameter curve. The impedance pairs are formed by the longitudinal wave impedance curve and the transverse wave impedance curve in the target elastic parameter curve corresponding to the longitudinal wave impedance and transverse wave impedance at the same depth.

[0074] Step A2: Correlate each impedance pair with the fluid saturation and pore pressure corresponding to the impedance pair at the same depth in the target geological parameter curve.

[0075] Step A3: Group and mark the target number of impedance pairs in the intersection domain of longitudinal wave impedance and transverse wave impedance, and determine the first transformation formula by linear fitting of the target number of impedance pairs based on fluid saturation, and determine the second transformation formula by linear fitting of the target number of impedance pairs based on pore pressure.

[0076] Specifically, based on the P-wave impedance and S-wave impedance curves at each depth in the target elastic parameter curves, impedance pairs corresponding to each depth can be formed, thus obtaining the target number of impedance pairs. For each impedance pair in the target number of impedance pairs, the fluid saturation and pore pressure corresponding to the same depth as the impedance pair can be determined from the target geological parameter curves and correlated with the impedance pair.

[0077] By grouping and labeling the target number of impedance pairs in the intersection region of P-wave and S-wave impedances, a linear fit can be performed to obtain the fitting function Zs = k × Zp - b, where k is the slope and b is the intercept. Substituting the two sets of values ​​(Zp1, Zs1) and (Zp2, Zs2) into the fitting function yields two equations: Zs1 = k × Zp1 - b and Zs2 = k × Zp2 - b. Subtracting these two equations and moving all terms to the right side, we obtain the transformation F(ΔZp, ΔZs) = k × ΔZp - ΔZs, where ΔZp = Zp2 - Zp1 and ΔZs = Zs2 - Zs1. This ensures that the slope obtained for the impedance values ​​Zp and Zs is also applicable to the impedance difference values ​​ΔZp and ΔZs.

[0078] Furthermore, based on the fluid saturation associated with the impedance pairs, linear fitting is performed on a target number of impedance pairs to obtain a linear fitting line under the same fluid saturation, which serves as the first fitting line. Thus, the first transformation formula can be determined based on the first fitting line. Based on the pore pressure associated with the impedance pairs, linear fitting is performed on a target number of impedance pairs to obtain a linear fitting line under the same pore pressure, which serves as the second fitting line. Thus, the second transformation formula can be determined based on the second fitting line.

[0079] As an optional embodiment of the present invention, a first transformation formula is determined by linear fitting of the target number of impedance pairs based on fluid saturation, and a second transformation formula is determined by linear fitting of the target number of impedance pairs based on pore pressure, including the following steps B1-B4:

[0080] Step B1: Based on the data density distribution under fluid saturation, perform linear fitting on impedance pairs associated with the same fluid saturation to obtain at least two first fitting lines.

[0081] Step B2: Determine the first transformation formula based on at least two first fitted lines.

[0082] Step B3: Based on the data density distribution under pore pressure, perform linear fitting on impedance pairs associated with the same pore pressure to obtain at least two second fitting lines.

[0083] Step B4: Determine the second transformation formula based on at least two second fitted lines.

[0084] Specifically, the data density distribution under fluid saturation can be used to describe the density of the target number of impedance pairs in the intersection region of P-wave and S-wave impedances under fluid saturation associated with impedance pairs. Similarly, the data density distribution under pore pressure can be used to describe the density of the target number of impedance pairs in the intersection region of P-wave and S-wave impedances under pore pressure associated with impedance pairs.

[0085] Specifically, for impedance pairs displaying the target number of impedances in the intersection region of longitudinal and transverse wave impedances, determining at least two first fitted lines based on the data density distribution under fluid saturation and at least two second fitted lines based on the data density distribution under pore pressure can improve the effectiveness and fitting efficiency of the first and second fitted lines. By determining the slope of each first fitted line, a first transformation formula can be determined based on the average slope of at least two first fitted lines. By determining the slope of each second fitted line, a second transformation formula can be determined based on the average slope of at least two second fitted lines.

[0086] refer to Figure 14When the lithology and physical properties of a reservoir are homogeneous, meaning the mineral content and porosity are constant, the fluid saturation and pressure variation trends are essentially constant within the intersection domain of P-wave impedance and S-wave impedance; that is, the slope of the fitted straight line is essentially constant. However, under actual conditions, the lithology and physical properties are heterogeneous, and the average slope of the fitted straight line can effectively account for actual conditions.

[0087] For example, refer to Figure 15 and Figure 16 Zp represents the longitudinal wave impedance value, and Zs represents the transverse wave impedance value. Figure 15 In the process, different markers are added to the fluid saturation associated with the impedance pairs of the target quantity, namely 100% gas saturation, 50% oil saturation, 50% water saturation, and 100% water saturation, to display the values. Linear fitting yields three first-fit lines. The slopes of each of the three first-fit lines are 0.572, 0.673, and 0.802, respectively, with an average slope of 0.682. Therefore, the first transformation formula F1(ΔZp,ΔZs) = 0.682 × ΔZp - ΔZs is obtained.

[0088] Figure 16 In the process, different markers are added to indicate the pore pressures associated with the target number of impedance pairs at 12000 psi, 10000 psi, and 8000 psi, respectively, thereby obtaining four second-fit lines through linear fitting. The slopes of each of the four second-fit lines are 0.178, 0.121, 0.102, and 0.074, respectively, with an average slope of 0.119. Therefore, the second transformation formula F2(ΔZp,ΔZs) = 0.119 × ΔZp - ΔZs.

[0089] S205. Based on the time-shifted seismic data of the target area, determine the P-wave impedance difference volume and S-wave impedance difference volume of the target area.

[0090] S206. Substitute the longitudinal wave impedance difference volume and the transverse wave impedance difference volume into the first transformation formula to obtain the fluid saturation change attribute volume. The first transformation formula is a linear function between the first data and the target impedance difference. The first transformation formula is determined based on a reference well. The reference well is a drilled well with complete geological parameter curve data and elastic parameter curve data in the target area. The first data is used to indicate the change of fluid saturation. The target impedance difference includes the longitudinal wave impedance difference and the transverse wave impedance difference.

[0091] S207. Substitute the longitudinal wave impedance difference volume and the transverse wave impedance difference volume into the second transformation formula to obtain the pore pressure change attribute volume. The second transformation formula is a linear function between the second data and the target impedance difference. The second transformation formula is determined based on the reference well. The second data is used to indicate the change of pore pressure.

[0092] S208. Based on the fluid saturation change attribute volume and pore pressure change attribute volume, identify the signals of fluid saturation change and pore pressure change in the research target area during time-lapse earthquakes.

[0093] The technical solution of this invention involves determining a reference geological parameter curve for a reference well, which includes: a mineral proportion curve, a porosity curve, an overburden pressure curve, a fluid saturation curve, and a pore pressure curve. A target geological parameter curve is obtained by modifying the fluid saturation curve and / or the pore pressure curve in the reference geological parameter curve. A target elastic parameter curve is obtained by performing rock physics forward modeling based on the target geological parameter curve, which includes a P-wave impedance curve and a S-wave impedance curve. A first transformation formula and a second transformation formula are determined based on the target geological parameter curve and the target elastic parameter curve. This achieves the establishment of the first and second transformation formulas through linear fitting and obtaining the average slope, improving the accuracy of the first and second transformation formulas and effectively adapting to the lithology and physical properties of the target reservoir. Given the heterogeneous nature of the target area, the study determines the P-wave impedance difference volume and S-wave impedance difference volume based on time-lapsed seismic data. Substituting these volumes into a first transformation equation yields the fluid saturation change attribute volume, which is a linear function of the difference between the first data and the target impedance. Substituting these volumes into a second transformation equation yields the pore pressure change attribute volume, which is a linear function of the difference between the second data and the target impedance. Based on these fluid saturation change and pore pressure change attribute volumes, the study identifies the signals of fluid saturation and pore pressure changes in the target area during time-lapsed seismic events, effectively decoupling the fluid and pressure signals by studying the changes in fluid saturation and pore pressure in the target area during time-lapsed seismic events.

[0094] Figure 17 This is a schematic diagram of a fluid and pressure decoupling device for time-lapse earthquakes provided in an embodiment of the present invention. This embodiment of the invention is applicable to situations where fluid saturation and pore pressure in a target area are decoupled and separated during time-lapse earthquake implementation. The device can be implemented in hardware and / or software. Figure 17 As shown, the fluid and pressure decoupling device in this time-lapse earthquake includes:

[0095] The first determining module 301 is used to determine the P-wave impedance difference body and the S-wave impedance difference body of the research target area based on the time-shifted seismic data of the research target area.

[0096] The first acquisition module 302 is used to substitute the longitudinal wave impedance difference body and the transverse wave impedance difference body into the first transformation formula to obtain the fluid saturation change attribute body. The first transformation formula is a linear function between the first data and the target impedance difference. The first transformation formula is determined based on the reference well. The reference well is a drilled well with complete geological parameter curve data and elastic parameter curve data in the target area. The first data is used to indicate the change of fluid saturation. The target impedance difference includes the longitudinal wave impedance difference and the transverse wave impedance difference.

[0097] The second acquisition module 303 is used to substitute the longitudinal wave impedance difference body and the transverse wave impedance difference body into the second transformation formula to obtain the pore pressure change attribute body. The second transformation formula is a linear function between the second data and the target impedance difference. The second transformation formula is determined based on the reference well. The second data is used to indicate the pore pressure change.

[0098] The identification module 304 is used to identify the signals of fluid saturation change and pore pressure change in the research target area during time-lapse earthquakes based on the fluid saturation change attribute volume and the pore pressure change attribute volume.

[0099] Based on any of the above-mentioned optional technical solutions, the fluid and pressure decoupling device in time-lapse seismic data may optionally further include: a second determining module, a third determining module, a fourth determining module, and a fifth determining module. The second determining module is used to determine the reference geological parameter curves of a reference well before determining the P-wave impedance difference body and S-wave impedance difference body of the research target area based on the time-lapse seismic data of the research target area. The reference geological parameter curves include: mineral proportion curves, porosity curves, overlying pressure curves, fluid saturation curves, and pore pressure curves. The third determining module is used to obtain the target geological parameter curves by modifying the fluid saturation curve and / or pore pressure curve in the reference geological parameter curves. The fourth determining module is used to obtain the target elastic parameter curves by performing rock physics forward modeling based on the target geological parameter curves. The target elastic parameter curves include P-wave impedance curves and S-wave impedance curves. The fifth determining module is used to determine the first transformation formula and the second transformation formula based on the target geological parameter curves and the target elastic parameter curves.

[0100] Based on any of the above optional technical solutions, optionally, the fourth determining module is specifically used to adjust the theoretical rock physics model based on the reference geological parameter curve and the reference elastic parameter curve until the elastic parameter curve obtained by the theoretical rock physics model through rock physics forward modeling based on the reference geological parameter curve matches the reference elastic parameter curve. Then, the theoretical rock physics model with adjusted parameters is used as the target area rock physics model. The reference elastic parameter curve includes the density curve, the P-wave impedance curve, and the S-wave impedance curve. The target elastic parameter curve is obtained by rock physics forward modeling based on the target geological parameter curve using the target area rock physics model.

[0101] Based on any of the above optional technical solutions, optionally, the fifth determining module includes: a sixth determining unit, an association unit, and a seventh determining unit. The sixth determining unit is used to determine the target number of impedance pairs based on the target elastic parameter curve, where each impedance pair is formed by the P-wave impedance curve and the S-wave impedance curve corresponding to the P-wave impedance and S-wave impedance at the same depth in the target elastic parameter curve; the association unit is used to associate each impedance pair with the fluid saturation and pore pressure corresponding to the impedance pair at the same depth in the target geological parameter curve; the seventh determining unit is used to group and mark the target number of impedance pairs displayed in the intersection region of the P-wave impedance and S-wave impedance, and determine a first transformation formula based on linear fitting of the target number of impedance pairs based on fluid saturation, and determine a second transformation formula based on linear fitting of the target number of impedance pairs based on pore pressure.

[0102] Based on any of the above optional technical solutions, optionally, the seventh determining unit is specifically used to perform linear fitting on impedance pairs associated with the same fluid saturation based on the data density distribution under fluid saturation to obtain at least two first fitting lines; determine a first transformation formula based on the at least two first fitting lines; perform linear fitting on impedance pairs associated with the same pore pressure based on the data density distribution under pore pressure to obtain at least two second fitting lines; and determine a second transformation formula based on the at least two second fitting lines.

[0103] Based on any of the above optional technical solutions, optionally, the first determining module 301 is specifically used to determine time-shifted earthquake difference data based on the monitoring data and baseline data of time-shifted earthquakes in the research target area, and to determine at least three target difference data volumes based on the time-shifted earthquake difference data. The target difference data volumes are obtained by angular superposition of the time-shifted earthquake difference data within a preset seismic wave incident angle range. Based on the at least three target difference data volumes, time-shifted earthquake pre-stack inversion is performed to determine the P-wave impedance difference volume and the S-wave impedance difference volume.

[0104] Based on any of the above optional technical solutions, optionally, the identification module 304 is specifically used to determine the fluid saturation change attribute plane map corresponding to the research target area based on the fluid saturation change attribute volume, and to determine the intensity and range of fluid saturation change in the research target area from the baseline to the monitoring seismic acquisition based on the fluid saturation change attribute plane map; and to determine the pore pressure change attribute plane map corresponding to the research target area based on the pore pressure change attribute volume, and to determine the intensity and range of pore pressure change in the research target area from the baseline to the monitoring seismic acquisition based on the pore pressure change attribute plane map.

[0105] The technical solution of this invention involves: a first determining module 301 determining the P-wave impedance difference volume and the S-wave impedance difference volume of the target area based on time-lapsed seismic data; a first acquiring module 302 substituting the P-wave impedance difference volume and the S-wave impedance difference volume into a first transformation formula to obtain a fluid saturation change attribute volume, where the first transformation formula is a linear function between the first data and the target impedance difference; and a second acquiring module 303 substituting the P-wave impedance difference volume and the S-wave impedance difference volume into a second transformation formula to obtain a pore pressure change attribute volume, where the second transformation formula is a linear function between the second data and the target impedance difference. The linear function between; the identification module 304 identifies the signals of fluid saturation change and pore pressure change in the research target area during time-lapse earthquakes based on the fluid saturation change attribute volume and the pore pressure change attribute volume. This realizes the description of the fluid saturation change in the research target area during time-lapse earthquakes by the fluid saturation change attribute volume and the description of the pore pressure change in the research target area during time-lapse earthquakes by the pore pressure change attribute volume. Thus, by studying the changes of fluid saturation and pore pressure in the research target area during time-lapse earthquakes, the fluid and pressure signals are effectively decoupled.

[0106] The fluid and pressure decoupling device in time-shifted earthquakes provided in this embodiment of the invention can execute the fluid and pressure decoupling method in time-shifted earthquakes provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0107] Figure 18 This is a schematic diagram of an electronic device for implementing a fluid and pressure decoupling method in time-lapse earthquakes, provided as an embodiment of the present invention. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0108] like Figure 18As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0109] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0110] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as fluid and pressure decoupling methods in time-lapsed seismic events.

[0111] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication unit 19, or installed from storage unit 18, or installed from ROM 12. When the computer program is executed by processor 11, it performs the functions defined in the methods of the embodiments of the present invention.

[0112] In some embodiments, the fluid and pressure decoupling method in time-shifted earthquakes can be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the fluid and pressure decoupling method in time-shifted earthquakes described above can be performed. Alternatively, in other embodiments, processor 11 can be configured to perform the fluid and pressure decoupling method in time-shifted earthquakes by any other suitable means (e.g., by means of firmware).

[0113] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip (SoCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0114] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0115] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0116] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0117] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0118] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0119] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0120] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for decoupling fluid and pressure in time-shifted earthquakes, characterized in that, The method includes: Based on time-shifted seismic data of the target area, the P-wave impedance difference volume and the S-wave impedance difference volume of the target area were determined. Substituting the longitudinal wave impedance difference body and the transverse wave impedance difference body into the first transformation formula yields the fluid saturation change attribute body. The first transformation formula is a linear function between the first data and the target impedance difference. The first transformation formula is determined based on a reference well. The reference well is a drilled well in the research target area with complete geological parameter curve data and elastic parameter curve data. The first data is used to indicate the change in fluid saturation. The target impedance difference includes the longitudinal wave impedance difference and the transverse wave impedance difference. Substituting the longitudinal wave impedance difference body and the transverse wave impedance difference body into the second transformation formula yields the pore pressure change attribute body. The second transformation formula is a linear function between the second data and the target impedance difference. The second transformation formula is determined based on the reference well. The second data is used to indicate the change in pore pressure. Based on the fluid saturation change attribute body and the pore pressure change attribute body, the signals of fluid saturation change and pore pressure change in the study target area during time-lapse earthquakes are identified.

2. The method according to claim 1, characterized in that, Before determining the P-wave impedance difference volume and S-wave impedance difference volume of the study target area based on time-shifted seismic data of the study target area, the following steps are also included: Determine the reference geological parameter curves of the reference well, which include: mineral proportion curve, porosity curve, overburden pressure curve, fluid saturation curve, and pore pressure curve; The target geological parameter curve is obtained by modifying the fluid saturation curve and / or pore pressure curve in the reference geological parameter curve; Based on the target geological parameter curve, a rock physics forward model is performed to obtain the target elastic parameter curve, which includes a longitudinal wave impedance curve and a transverse wave impedance curve. The first transformation formula and the second transformation formula are determined based on the target geological parameter curve and the target elastic parameter curve.

3. The method according to claim 2, characterized in that, Based on the target geological parameter curve, a rock physics forward modeling is performed to obtain the target elastic parameter curve, including: The theoretical rock physics model is adjusted based on the reference geological parameter curve and the reference elastic parameter curve until the elastic parameter curve obtained by the theoretical rock physics model through rock physics forward modeling based on the reference geological parameter curve matches the reference elastic parameter curve. The theoretical rock physics model with adjusted parameters is then used as the target area rock physics model. The reference elastic parameter curve includes the density curve, the longitudinal wave impedance curve, and the transverse wave impedance curve. The target elastic parameter curve is obtained by performing forward rock physics modeling based on the target geological parameter curve using the target area rock physics model.

4. The method according to claim 2, characterized in that, Determining the first transformation formula and the second transformation formula based on the target geological parameter curve and the target elastic parameter curve includes: Based on the target elastic parameter curve, the target number of impedance pairs is determined. The impedance pairs are formed by the longitudinal wave impedance curve and the transverse wave impedance curve in the target elastic parameter curve at the same depth, corresponding to the longitudinal wave impedance and transverse wave impedance. Each impedance pair is correlated with the fluid saturation and pore pressure at the same depth as the impedance pair in the target geological parameter curve; The target number of impedance pairs are grouped and marked in the intersection region of longitudinal and transverse impedances, and the first transformation is determined by linear fitting of the target number of impedance pairs based on fluid saturation, and the second transformation is determined by linear fitting of the target number of impedance pairs based on pore pressure.

5. The method according to claim 4, characterized in that, The first transformation formula is determined by linearly fitting the impedance pairs of the target quantity based on fluid saturation, and the second transformation formula is determined by linearly fitting the impedance pairs of the target quantity based on pore pressure, including: Based on the data density distribution under fluid saturation, at least two first fitting lines are obtained by linear fitting of impedance pairs with the same fluid saturation. The first transformation formula is determined based on the at least two first fitted straight lines; Based on the data density distribution under pore pressure, at least two second fitting lines are obtained by linear fitting of impedance pairs associated with the same pore pressure. The second transformation is determined based on the at least two second fitted lines.

6. The method according to claim 1, characterized in that, Based on time-shifted seismic data of the target area, the P-wave impedance difference volume and S-wave impedance difference volume of the target area are determined, including: Based on the monitoring data and baseline data of time-shifted earthquakes in the research target area, time-shifted earthquake difference data is determined, and at least three target difference data volumes are determined based on the time-shifted earthquake difference data. The target difference data volumes are obtained by angular superposition of the time-shifted earthquake difference data within a preset seismic wave incident angle range. Based on the at least three target difference data volumes, time-shifted pre-stack seismic inversion is performed to determine the P-wave impedance difference volume and the S-wave impedance difference volume.

7. The method according to claim 1, characterized in that, Based on the fluid saturation change attribute volume and the pore pressure change attribute volume, the signals of fluid saturation change and pore pressure change in the study target area during time-lapsed earthquakes are identified, including: Based on the fluid saturation change attribute volume, a fluid saturation change attribute plane map corresponding to the research target area is determined, and based on the fluid saturation change attribute plane map, the intensity and range of fluid saturation change in the research target area from the baseline to the monitoring seismic acquisition are determined; Based on the pore pressure change attribute volume, a pore pressure change attribute plane map corresponding to the research target area is determined, and based on the pore pressure change attribute plane map, the intensity and spread of pore pressure change in the research target area from the baseline to the monitoring seismic acquisition period are determined.

8. A fluid and pressure decoupling device for time-shifted earthquakes, characterized in that, The device includes: The first determining module is used to determine the P-wave impedance difference volume and the S-wave impedance difference volume of the research target area based on the time-shifted seismic data of the research target area. The first acquisition module is used to substitute the longitudinal wave impedance difference body and the transverse wave impedance difference body into the first transformation formula to obtain the fluid saturation change attribute body. The first transformation formula is a linear function between the first data and the target impedance difference. The first transformation formula is determined based on a reference well. The reference well is a drilled well in the research target area with complete geological parameter curve data and elastic parameter curve data. The first data is used to indicate the change of fluid saturation. The target impedance difference includes the longitudinal wave impedance difference and the transverse wave impedance difference. The second acquisition module is used to substitute the longitudinal wave impedance difference body and the transverse wave impedance difference body into the second transformation formula to obtain the pore pressure change attribute body. The second transformation formula is a linear function between the second data and the target impedance difference. The second transformation formula is determined based on the reference well. The second data is used to indicate the change of pore pressure. The identification module is used to identify the signals of fluid saturation change and pore pressure change in the research target area during time-lapse earthquakes based on the fluid saturation change attribute body and the pore pressure change attribute body.

9. An electronic device, characterized in that, The electronic device includes: At least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the fluid and pressure decoupling method in time-shifted earthquakes as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the fluid and pressure decoupling method in time-shifted earthquakes as described in any one of claims 1-7.

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