A method and device for calculating a synthetic seismic record based on Q compensation

Abstract

This invention discloses a method and apparatus for calculating synthetic seismic records based on Q-compensation. The calculation method includes calculating a full-band velocity curve based on reservoir elastic parameters and determining the frequency values ​​corresponding to a first frequency and a second frequency; calculating the compressibility modulus corresponding to the first frequency and the second frequency based on well logging curves and reservoir elastic parameters; calculating a quality factor curve based on the compressibility modulus corresponding to the first frequency and the second frequency; and calculating a Q-compensated synthetic seismic record based on the quality factor curve. This invention utilizes well logging data and reservoir elastic parameters to calculate the compressibility modulus of the first frequency and the second frequency, thereby obtaining the quality factor curve. Then, based on a convolution model, it integrates P-wave velocity, density, and the quality factor curve to calculate the Q-compensated synthetic seismic record. The Q-compensated synthetic seismic record can more realistically reflect the amplitude energy of seismic waves propagating in actual formations, improving the accuracy and precision of well-seismic calibration.

Description

Technical Field

[0001] This invention belongs to the field of petroleum geophysical exploration technology, and specifically relates to a method and apparatus for calculating synthetic seismic records based on Q compensation. Background Technology

[0002] Synthetic seismic record calibration is a crucial method for establishing a link between time-domain seismic data and depth-domain well logging data. A correct synthetic seismic record ensures the reasonableness of formation velocities. Conventional synthetic seismic record production involves converting sonic logging or VSP data into well-side seismic traces through mathematical operations. During the calculation process, only the quality of the sonic and density logging curves is typically considered. For collapse phenomena or abnormal pressure conditions in mudstone formations, environmental corrections are required first. Then, the reflection coefficient is calculated using qualified well logging curves. Subsequently, the reflection coefficient is convolved with the extracted seismic wavelet to obtain the final synthetic seismic record, which is used for waveform comparison with well-side seismic traces to obtain reasonable velocity relationships.

[0003] As oil exploration deepens, seismic exploration targets become increasingly refined. This necessitates meticulous precision and accuracy at every step of seismic data interpretation, including the creation of precise synthetic seismic record (SSR) calibration. The results of SSR calibration determine the accuracy of wellhead formation velocities. Given depth-domain logging stratification, velocity relationships determine the calibration location of time-domain seismic interpretation horizons, thus impacting the interpretation of the target horizon across the entire seismic work area. The criteria for judging the rationality of SSR calibration are twofold: first, whether the SSR matches the well-side seismic traces, including energy and wave impedance characteristics; and second, whether multiple wells within the same structural zone in the work area exhibit similar time-depth correspondences. A qualified SSR calibration generally must simultaneously meet both of these criteria. The main factors influencing SSR calibration results include: seismic wavelet extraction, logging curve correction, and the quality of the seismic data. Generally, a reasonable seismic wavelet and correct logging curves can effectively ensure the quality of synthetic seismic records. However, further refining the well-seismic calibration process requires considering the differences between logging and seismic measurement methods, and the inherent differences in the measurement results. According to rock physics research, seismic waves experience energy attenuation and velocity dispersion when propagating in saturated fluid media, leading to distortion of seismic amplitude. However, according to logging principles, acoustic logging curves characterize the travel time per unit distance of compressive waves, while density curves measure formation bulk density based on the photoelectric effect. Neither type of logging curve considers the absorption and attenuation effects of the formation. Therefore, the differences between these two measurement methods directly affect the matching relationship between well-bypass seismic data and synthetic seismic records. Based on this understanding, during the refined synthetic seismic record calibration process, attenuation correction, i.e., Q (quality factor) compensation, should be performed on the synthetic seismic record calculated based on logging curves to more accurately reflect the elastic properties of the formation and achieve a better match with the seismic data. Summary of the Invention

[0004] To address the above problems, this invention discloses a method for calculating synthetic seismic records based on Q-compensation, comprising:

[0005] Calculate the full-band velocity curve based on reservoir elastic parameters, and determine the frequency values ​​corresponding to the first and second frequencies;

[0006] Calculate the compression modulus corresponding to the first and second frequencies based on well logging curves and reservoir elastic parameters;

[0007] The quality factor curve is calculated based on the compression modulus corresponding to the first and second frequencies.

[0008] Synthetic seismic records with Q-compensation calculated based on quality factor curves.

[0009] Furthermore, the reservoir elastic parameters include reservoir rock matrix elastic parameters and pore fluid elastic parameters;

[0010] The elastic parameters of the reservoir rock matrix include the bulk modulus of rock mineral particles and the density of rock mineral particles;

[0011] The pore fluid elastic parameters include the bulk modulus of formation water and the bulk modulus of saturated gas.

[0012] Furthermore, the calculation of the full-band velocity curve based on reservoir elastic parameters and the determination of the frequency values ​​corresponding to the first and second frequencies include the following steps:

[0013] The reservoir elastic parameters are substituted into the rock physics model to calculate the full-band velocity curve;

[0014] The full-band velocity curve is differentiated with respect to frequency to obtain the frequency values ​​of the first and second frequencies corresponding to the determination threshold when the derivative result is less than the determination threshold.

[0015] The first frequency is greater than the second frequency.

[0016] Furthermore, the well logging curves are obtained through the following steps:

[0017] Acquire well logging data and derive well logging curves based on the well logging data;

[0018] The well logging data includes P-wave velocity curves, S-wave velocity curves, density curves, porosity curves, and water saturation curves.

[0019] Furthermore, the calculation of the compression modulus corresponding to the first and second frequencies based on the logging curves and reservoir elastic parameters includes the following steps:

[0020] Substitute the well logging curves into the rock physics model to calculate the velocity curves corresponding to the first and second frequencies, and then obtain the compression modulus curves under the first and second frequency conditions.

[0021] Furthermore, the quality factor curve is determined by the following formula:

[0022]

[0023] Among them, M high M is the compression modulus at the first frequency. low Q is the second frequency compression modulus. -1 It is the reciprocal of the quality factor.

[0024] Furthermore, the synthetic seismic record is determined using the following formula:

[0025] s = conv(w, R) * exp(-πftQ) -1 )

[0026] Where s is the synthetic seismic record, w is the Ricker wavelet, R is the reflection coefficient, f is the frequency, t is the time, conv is the convolution operation, and exp is the exponential operation;

[0027] The reflection coefficient R is determined by the following formula:

[0028]

[0029] Where den is the density curve, Vp is the P-wave velocity curve, j is 1 to WN, and WN is the number of sampling points for the logging curve;

[0030] The Ricker wavelet w is determined by the following formula:

[0031] w = (1 - 2(πft)) 2 )exp(-(πft) 2 ).

[0032] A Q-compensated synthetic seismic record calculation device, comprising:

[0033] The frequency determination unit is used to calculate the full-band velocity curve based on the reservoir elastic parameters and determine the frequency values ​​corresponding to the first and second frequencies.

[0034] The compression modulus determination unit is used to calculate the compression modulus corresponding to the first and second frequencies based on the logging curves and reservoir elastic parameters.

[0035] The quality factor calculation unit is used to calculate the quality factor curve based on the compression modulus corresponding to the first and second frequencies.

[0036] Synthetic seismic record unit, used to calculate Q-compensated synthetic seismic records based on quality factor curves.

[0037] Furthermore, the synthetic seismic record computing device further includes: an acquisition unit;

[0038] The acquisition unit is used to acquire well logging data and obtain well logging curves based on the well logging data;

[0039] The well logging data includes P-wave velocity curves, S-wave velocity curves, density curves, porosity curves, and water saturation curves.

[0040] Furthermore, the frequency determination unit is also used for:

[0041] The reservoir elastic parameters are substituted into the rock physics model to calculate the full-band velocity curve;

[0042] The full-band velocity curve is differentiated with respect to frequency to obtain the frequency values ​​of the first and second frequencies corresponding to the determination threshold when the derivative result is less than the determination threshold.

[0043] The first frequency is greater than the second frequency.

[0044] Furthermore, the compression modulus determining unit is also used for:

[0045] Substitute the well logging curves into the rock physics model to calculate the velocity curves corresponding to the first and second frequencies, and then obtain the compression modulus curves under the first and second frequency conditions.

[0046] Compared with the prior art, the embodiments of the present invention have at least the following advantages: Addressing the problem of missing amplitude energy Q-compensation in the conventional synthetic seismic record production process, the present invention proposes a method and apparatus for calculating synthetic seismic records based on conventional well logging curves to obtain quality factor curves and perform Q-compensation. This method uses well logging data and reservoir elastic parameters to calculate the compression modulus of the first and second frequencies using a patch saturation theory rock physics model, thereby obtaining the quality factor curve. Then, based on the convolution model, it calculates the Q-compensated synthetic seismic record by integrating P-wave velocity, density, and the quality factor curve. The Q-compensated synthetic seismic record can more realistically reflect the amplitude energy of seismic waves propagating in actual formations, effectively improving the accuracy and precision of well-seismic calibration and reducing the risks of exploration and development.

[0047] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention can be realized and obtained by means of the structures pointed out in the description and the drawings. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 A flowchart of a Q-compensation-based synthetic seismic record calculation method according to an embodiment of the present invention is shown;

[0050] Figure 2 Well logging curves according to an embodiment of the present invention are shown;

[0051] Figure 3A graph showing the relationship between full-band velocity and velocity derivative according to an embodiment of the present invention is shown;

[0052] Figure 4 The curve of the reciprocal of the quality factor (1 / Q) according to an embodiment of the present invention is shown;

[0053] Figure 5 A comparison diagram of the synthesized seismic records before and after Q-compensation according to an embodiment of the present invention is shown;

[0054] Figure 6 A schematic diagram of a Q-compensated synthetic seismic record calculation apparatus according to an embodiment of the present invention is shown. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] like Figure 1 As shown, the present invention proposes a method for calculating synthetic seismic records based on Q-compensation, which includes the following steps:

[0057] Step S101: Acquire well logging data and obtain well logging curves based on the well logging data;

[0058] During the process, the logging data includes the target well's P-wave velocity profile (Vp), in km / s; S-wave velocity profile (Vs), in km / s; and density profile (den), in g / cm³. 3 Porosity curve (por) and water saturation curve (Sw). Figure 2 The input logging data is displayed, with the target interval depth ranging from 5240ft to 5400ft, and the target interval being a high-yield gas layer.

[0059] Step S102: Calculate the full-band velocity curve based on the reservoir elastic parameters, and determine the frequency values ​​corresponding to the first and second frequencies;

[0060] Reservoir elastic parameters include reservoir matrix elastic parameters and pore fluid elastic parameters;

[0061] During implementation, the elastic parameters of the reservoir rock matrix include the bulk modulus K0 of the rock mineral particles (in GPa) and the density ρ0 of the rock mineral particles (in g / cm³). 3 ).

[0062] Pore ​​fluid elastic parameters include the bulk modulus of formation water and the bulk modulus of saturated gas;

[0063] Formation water bulk modulus K w The unit is GPa, and the viscosity coefficient η of formation water is... w The unit is Pas, and the density ρ of formation water is... w The unit is g / cm³ 3 ; Bulk modulus K of saturated gas g The unit is GPa, and the viscosity coefficient η of saturated gas. g The unit is Pas, and the density ρ of saturated gas is... g The unit is g / cm³ 3 κ represents matrix permeability, expressed in mD.

[0064] During implementation, the full-frequency velocity curve was calculated using the patch saturation theory rock physics model. The calculation process is as follows:

[0065] First, the bulk modulus K of the rock framework is calculated based on the bulk modulus of rock mineral grains. dry With shear modulus u dry The calculation formula is as follows:

[0066] K dry =K0*(1-por) 4 / (1-por)

[0067] μ dry =den*V s 2

[0068] Where por is porosity, K0 is the bulk modulus of rock mineral particles in GPa, and den is density in g / cm³. 3 Vs is the transverse wave velocity, with units of km / s.

[0069] According to the patch saturation theory rock physics model, the expression for the compressibility modulus of seismic waves propagating in a partially saturated fluid medium is:

[0070]

[0071] M0 = 1 / (S) w / M water +(1-S w ) / M gas )

[0072] Where M0 is the average compressive modulus of the saturated fluid mixture, in GPa, M water This is the compressibility modulus when saturated with water, expressed in GPa and M. gas I is the compressibility modulus of saturated gas, expressed in GPa. wI is the slow longitudinal wave impedance in saturated water, expressed in km / s * g / cm³. g The slow longitudinal wave impedance at saturation is given by r in km / s g / cm³. w The stress gradient when water is saturated, r g Let ω be the stress gradient when the gas is saturated, ω be the angular frequency, L be the characteristic length of the saturated heterogeneous body (usually 0.1–0.2 m), and i be the imaginary unit. Preferably, L is 0.1 m.

[0073] In the formula, ω = 2πf, where f is the frequency.

[0074] The compressibility modulus of a fully saturated fluid can be calculated using the Gassmann formula, as shown below:

[0075]

[0076]

[0077] The stress gradient of a saturated fluid can be calculated by the ratio of the total stress induced by the fluid to the vertical stress when there is no fluid flow, as shown in the following formula:

[0078]

[0079]

[0080] Where b is the Biot coefficient, E w The elastic modulus of formation water is expressed in GPa and E. g This is the elastic modulus of saturated gas, expressed in GPa.

[0081]

[0082]

[0083]

[0084] The expression for the slow longitudinal wave impedance when saturated with different fluids is:

[0085]

[0086]

[0087] in,

[0088]

[0089]

[0090] In the formula, k wThe complex wave number of the slow longitudinal wave when the water is saturated, in meters. -1 η w κ is the viscosity coefficient of formation water, in Pas, and k is the matrix permeability, in mD. g The complex wave number of the slow longitudinal wave in saturated gas, in meters. -1 η g is the viscosity coefficient of saturated gas, in Pas, and i is the imaginary unit.

[0091] Finally, the full-band velocity can be calculated based on the compressibility modulus M propagating in a partially saturated fluid medium, as expressed by:

[0092]

[0093] The full-band velocity curve is differentiated with respect to frequency to obtain the derivative of velocity with respect to frequency. The first and second frequencies corresponding to the condition that the derivative is less than a threshold are then determined. The first frequency is greater than the second frequency.

[0094] When the derivative of speed with respect to frequency is 0, it indicates that the speed no longer changes with frequency. There are two corresponding frequencies at this point: a low-frequency limit (the second frequency) at the low-frequency end and a high-frequency limit (the first frequency) at the high-frequency end. In practice, the derivative of speed with respect to frequency will approach 0 infinitely, but will not reach zero. Therefore, a threshold value needs to be set. When the derivative of speed with respect to frequency is less than this threshold, the frequency limit is considered to have been reached. The threshold value ranges from 0 to 0.00001. In some embodiments, the threshold value is set to 0.00001. The low-frequency end is lower than the high-frequency end.

[0095] like Figure 3 The figure shows the full-band velocity and the velocity-frequency derivative relationship obtained during the implementation. The horizontal axis represents frequency in Hz, the left vertical axis represents P-wave velocity in km / s, and the right vertical axis represents the P-wave velocity derivative. The solid black line represents the full-band velocity curve, and the dashed black line represents the P-wave velocity-frequency derivative curve. The figure shows that as the frequency changes, the P-wave velocity curve approaches constant at both low and high frequencies, while the velocity value changes significantly in the middle frequency range. Overall, the velocity gradually increases with increasing frequency, which is consistent with rock physics theory. Regarding the P-wave velocity derivative curve, it can be seen that the derivative value approaches 0 at both low and high frequencies, and the velocity-frequency derivative curve reaches its maximum value in the middle frequency range. According to our set judgment threshold, when the frequency is less than 10... -1 Hz and greater than 10 5 At Hz, the derivative of velocity with respect to frequency reaches a threshold value, and the derivative is considered to be approximately zero. Therefore, the first frequency is determined to be 10. 5Hz, the frequency value of the second frequency is 10. -1 Hz.

[0096] Step S103: Calculate the compression modulus corresponding to the first and second frequencies based on the logging curves and reservoir elastic parameters;

[0097] Substitute the well logging curves into the rock physics model to calculate the velocity curves corresponding to the first and second frequencies, and then obtain the compression modulus curves under the first and second frequency conditions.

[0098] Specifically, the first and second frequencies are substituted into the above full-band velocity formula to obtain the corresponding velocity curve, and then the corresponding compression modulus curve is obtained through the following formula.

[0099] During implementation, according to the calculation process in step 103, the second frequency is calculated to be 10. -1 Hz and the first frequency is 10 5 The compressive modulus corresponding to Hz is expressed as:

[0100]

[0101]

[0102] In the formula, ω high I whigh I ghigh This indicates that the frequency f = 10 during the calculation process. 5 The physical quantity corresponding to Hz, M high For the first frequency compression modulus, similarly, ω low I wlow I glow This indicates that the frequency f = 10 during the calculation process. -1 The physical quantity corresponding to Hz, M low is the second frequency compression modulus, and i is the imaginary unit.

[0103] Step S104: Calculate the quality factor curve based on the compression modulus corresponding to the first and second frequencies;

[0104] During implementation, based on the definition of quality factor (Q), the quality factor curve is calculated using the compressive modulus corresponding to the first and second frequencies. The calculation formula is shown below:

[0105]

[0106] Among them, Q -1 It is the reciprocal of the quality factor. Figure 4The figure shows the reciprocal curve of the calculated quality factor, i.e. the attenuation curve. It can be seen from the figure that the presence of pore fluid leads to a decrease in the formation quality factor (enhanced absorption and attenuation). When seismic waves pass through formations with low quality factors, strong energy attenuation occurs, which eventually leads to distortion of amplitude energy.

[0107] Step S105: Calculate the Q-compensated synthetic seismic record based on the quality factor curve.

[0108] During implementation, using the input P-wave velocity and density curves, as well as the calculated quality factor curve, the formula for calculating Q-compensated synthetic seismic records can be obtained according to the convolution formula, as shown below:

[0109] s = conv(w, R) * exp(-πftQ) -1 )

[0110] Where s is the synthetic seismic record, w is the Ricker wavelet, R is the reflection coefficient, f is the frequency, t is the time, conv is the convolution operation, and exp is the exponential operation;

[0111] The reflection coefficient R is determined by the following formula:

[0112]

[0113] Where den is the density curve, Vp is the P-wave velocity curve, j is 1 to WN, and WN is the number of sampling points for the logging curve;

[0114] Ricker wavelet w is determined by the following formula:

[0115] w = (1 - 2(πft)) 2 )exp(-(πft) 2 ).

[0116] Figure 5A comparison of the synthesized seismic records before and after Q-compensation is shown. The black dashed line represents the synthesized seismic record before Q-compensation, and the black solid line represents the synthesized seismic record after Q-compensation. The figure shows that in the target layer (5240 ft to 5400 ft), the formation quality factor decreases due to saturated gas, resulting in significantly enhanced attenuation of seismic waves during propagation. This leads to a noticeable reduction in amplitude energy after Q-compensation. However, in non-target layers (depths less than 5240 ft and greater than 5400 ft), the formation quality factor is high due to the absence of gas, resulting in minimal attenuation of seismic waves. Consequently, there is no significant difference in energy between the synthesized and non-Q-compensated seismic records, which is consistent with rock physics theory and actual seismic observations. This comparison confirms that this method can effectively compensate for amplitude energy distortion caused by seismic waves propagating in oil and gas-bearing reservoirs, ensuring a consistent energy variation trend between the synthesized seismic record and wellbore seismic data. This improves the accuracy of wellbore calibration, thereby enhancing the precision of seismic data interpretation and reducing exploration and development risks.

[0117] Based on the above-described Q-compensation-based synthetic seismic record calculation method, this embodiment proposes a Q-compensation-based synthetic seismic record calculation device, such as... Figure 6 As shown, it includes:

[0118] The frequency determination unit is used to calculate the full-band velocity curve based on the reservoir elastic parameters and determine the frequency values ​​corresponding to the first and second frequencies.

[0119] The compression modulus determination unit is used to calculate the compression modulus corresponding to the first and second frequencies based on the logging curves and reservoir elastic parameters.

[0120] The quality factor calculation unit is used to calculate the quality factor curve based on the compression modulus corresponding to the first and second frequencies.

[0121] Synthetic seismic record unit, used to calculate Q-compensated synthetic seismic records based on quality factor curves.

[0122] The synthetic seismic record computing device also includes: an acquisition unit;

[0123] The acquisition unit is used to acquire well logging data and obtain well logging curves based on the well logging data;

[0124] The well logging data includes P-wave velocity curves, S-wave velocity curves, density curves, porosity curves, and water saturation curves.

[0125] The frequency determination unit is also used for:

[0126] The reservoir elastic parameters are substituted into the rock physics model to calculate the full-band velocity curve;

[0127] The full-band velocity curve is differentiated with respect to frequency to obtain the frequency values ​​of the first and second frequencies corresponding to the determination threshold when the derivative result is less than the determination threshold.

[0128] The first frequency is greater than the second frequency.

[0129] The compression modulus determination unit is also used for:

[0130] Substitute the well logging curves into the rock physics model to calculate the velocity curves corresponding to the first and second frequencies, and then obtain the compression modulus curves under the first and second frequency conditions.

[0131] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating synthetic seismic records based on Q-compensation, characterized in that, include: Calculate the full-band velocity curve based on reservoir elastic parameters, and determine the frequency values ​​corresponding to the first and second frequencies; Calculate the compression modulus corresponding to the first and second frequencies based on well logging curves and reservoir elastic parameters; The quality factor curve is calculated based on the compression modulus corresponding to the first and second frequencies. Synthetic seismic records for Q-compensation calculated based on quality factor curves; The synthetic seismic record is determined using the following formula: in, s To synthesize seismic records, w For Ricker subwavelength, R The reflection coefficient, f For frequency, t For time, conv is the convolution operation, and exp is the exponentiation operation; The reflectance coefficient R Determined by the following formula: Where den is the density curve, Vp is the P-wave velocity curve, j is 1~WN, and WN is the number of sampling points for the logging curve.

2. The method for calculating synthetic seismic records based on Q-compensation according to claim 1, characterized in that, The reservoir elastic parameters include reservoir rock matrix elastic parameters and pore fluid elastic parameters; The elastic parameters of the reservoir rock matrix include the bulk modulus of rock mineral particles and the density of rock mineral particles; The pore fluid elastic parameters include the bulk modulus of formation water and the bulk modulus of saturated gas.

3. The method for calculating synthetic seismic records based on Q-compensation according to claim 1, characterized in that, The process of calculating the full-band velocity curve based on reservoir elastic parameters and determining the frequency values ​​corresponding to the first and second frequencies includes the following steps: The reservoir elastic parameters are substituted into the rock physics model to calculate the full-band velocity curve; The full-band velocity curve is differentiated with respect to frequency to obtain the frequency values ​​of the first and second frequencies corresponding to the determination threshold when the derivative result is less than the determination threshold. The first frequency is greater than the second frequency.

4. The method for calculating synthetic seismic records based on Q-compensation according to claim 1, characterized in that, The logging curves are obtained through the following steps: Acquire well logging data and derive well logging curves based on the well logging data; The well logging data includes P-wave velocity curves, S-wave velocity curves, density curves, porosity curves, and water saturation curves.

5. The method for calculating synthetic seismic records based on Q-compensation according to claim 1, characterized in that, The calculation of the compression modulus corresponding to the first and second frequencies based on well logging curves and reservoir elastic parameters includes the following steps: Substitute the well logging curves into the rock physics model to calculate the velocity curves corresponding to the first and second frequencies, and then obtain the compression modulus curves under the first and second frequency conditions.

6. The method for calculating synthetic seismic records based on Q-compensation according to claim 1, characterized in that, The quality factor curve is determined by the following formula: in, M high The first frequency compression modulus, M low The second frequency compression modulus, Q -1 It is the reciprocal of the quality factor.

7. The method for calculating synthetic seismic records based on Q-compensation according to claim 1, characterized in that, The Ricker wavelet w Determined by the following formula: 。 8. A synthetic seismic record calculation device based on Q-compensation, characterized in that, include: The frequency determination unit is used to calculate the full-band velocity curve based on the reservoir elastic parameters and determine the frequency values ​​corresponding to the first and second frequencies. The compression modulus determination unit is used to calculate the compression modulus corresponding to the first and second frequencies based on the logging curves and reservoir elastic parameters. The quality factor calculation unit is used to calculate the quality factor curve based on the compression modulus corresponding to the first and second frequencies. Synthetic seismic record unit, used to calculate Q-compensated synthetic seismic records based on quality factor curves; The synthetic seismic record is determined using the following formula: in, s To synthesize seismic records, w For Ricker subwavelength, R The reflection coefficient, f For frequency, t For time, conv is the convolution operation, and exp is the exponentiation operation; The reflectance coefficient R Determined by the following formula: Where den is the density curve, Vp is the P-wave velocity curve, j is 1~WN, and WN is the number of sampling points for the logging curve.

9. The synthetic seismic record calculation device based on Q-compensation according to claim 8, characterized in that, The synthetic seismic record computing device further includes: an acquisition unit; The acquisition unit is used to acquire well logging data and obtain well logging curves based on the well logging data; The well logging data includes P-wave velocity curves, S-wave velocity curves, density curves, porosity curves, and water saturation curves.

10. The Q-compensated synthetic seismic record calculation device according to claim 8 or 9, characterized in that, The frequency determination unit is further configured to: The reservoir elastic parameters are substituted into the rock physics model to calculate the full-band velocity curve; The full-band velocity curve is differentiated with respect to frequency to obtain the frequency values ​​of the first and second frequencies corresponding to the determination threshold when the derivative result is less than the determination threshold. The first frequency is greater than the second frequency.

11. The synthetic seismic record calculation device based on Q-compensation according to claim 8, characterized in that, The compression modulus determining unit is further configured to: Substitute the well logging curves into the rock physics model to calculate the velocity curves corresponding to the first and second frequencies, and then obtain the compression modulus curves under the first and second frequency conditions.

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