Carbonate rock ancient landform restoration method based on reservoir-geography ratio

Abstract

The invention belongs to the field of reservoir prediction in the petroleum industry, and particularly relates to a carbonate rock ancient landform recovery method based on the reservoir thickness of a target stratum, which comprises the following steps: calculating the stratum thickness of the target stratum, predicting the reservoir thickness of the target stratum, obtaining the reservoir thickness of the target stratum, and obtaining the ancient landform of the target stratum according to the reservoir thickness of the target stratum. According to the carbonate rock ancient landform recovery method based on the reservoir-geography ratio, the reservoir thickness of the target layer is predicted through neutron curve and pseudo-acoustic curve inversion, then the reservoir-geography ratio is calculated through a well-seismic fusion method, the ancient landform of the target layer is recovered, the ancient landform recovery precision is effectively improved, and the exploration and development success rate is improved.

Description

Technical Field

[0001] This invention belongs to the field of reservoir prediction in the petroleum industry, specifically involving a method for restoring paleogeography of carbonate rocks based on the reservoir-to-land ratio. Background Technology

[0002] Carbonate rocks are an important area of ​​oil and gas exploration, and accurately reconstructing paleogeography is crucial for predicting the distribution of high-quality reservoirs. Furthermore, paleogeographic maps are one of the essential foundational maps for work in carbonate rock oil and gas exploration, including delineating paleogeographic units, finely characterizing sedimentary facies, determining the distribution of high-quality reservoirs, and predicting oil and gas reservoir distribution.

[0003] Exploration practice shows that the reservoir properties of carbonate rocks are closely related to paleogeography. Therefore, paleogeography restoration has become a hot topic in carbonate reservoir research, but paleogeography restoration is usually very difficult.

[0004] Existing paleogeographic restoration methods can be broadly categorized into: residual stratigraphic thickness method, imprinting method, fill-in method, layer flattening method, sedimentological analysis method, error simulation method, sequence stratigraphy method, and stripping method. Currently, residual stratigraphic thickness method and imprinting method are mostly used for the restoration of paleogeographic features in carbonate rocks, making the restoration process simple and easy to operate. However, these methods have relatively low accuracy, and restoration is essentially impossible in cases of severe stratigraphic erosion.

[0005] To further improve the accuracy of paleogeographic reconstruction using the residual stratum thickness method, this invention proposes a method for paleogeographic reconstruction of carbonate rocks based on the reservoir-to-land ratio, which addresses the aforementioned problems. Summary of the Invention

[0006] The purpose of this invention is to provide a method for paleogeographic reconstruction of carbonate rocks based on reservoir-to-landform ratio. Through precise well-seismic calibration, inversion, and optimization analysis, this method efficiently and accurately calculates the formation thickness of the target layer, predicts reservoir thickness, and reconstructs paleogeography. This method improves the accuracy and efficiency of oil and gas exploration, and is applicable not only to cases of severe formation erosion but also to improving the accuracy of paleogeographic reconstruction.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for paleogeographic reconstruction of carbonate rocks based on reservoir-to-land ratio includes the following steps:

[0009] Calculate the formation thickness of the target layer, predict the reservoir thickness of the target layer, and obtain the reservoir-to-land ratio of the target layer;

[0010] The difference between the reservoir ratio of the target layer and the reservoir ratio of a single well is obtained, and the difference is then interpolated into a grid to obtain gridded interpolated data.

[0011] The interpolated data of the difference gridded interpolation is merged with the reservoir ratio data of the target layer to obtain the paleogeography of the target layer.

[0012] Furthermore, calculating the formation thickness of the target layer includes the following steps:

[0013] Through fine-tuning of well seismic data, the seismic reflection characteristics of the top and bottom boundaries of the target layer are determined;

[0014] The seismic reflection characteristics are spatially deconstructed to obtain a three-dimensional stratigraphic model. The seismic horizons of the top and bottom boundaries of the target layer are obtained from the three-dimensional stratigraphic model. The seismic thickness is obtained based on the seismic horizons of the top and bottom boundaries of the target layer.

[0015] The seismic thickness is corrected, and the thickness of the target layer is obtained after correction.

[0016] Furthermore, the calibration includes the following steps:

[0017] Statistical analysis of the formation thickness and seismic thickness of the target layer in drilled wells, and calculation of correction factors;

[0018] Based on the correction coefficients, grid interpolation is performed to obtain the planar distribution of the correction coefficients;

[0019] The thickness of the target layer is obtained by using the gridded data with correction coefficients and the extracted seismic horizons at the top and bottom of the target layer.

[0020] Furthermore, predicting the reservoir thickness of the target layer includes the following steps:

[0021] By reconstructing the neutron curve and the acoustic curve, a pseudo-acoustic curve is obtained;

[0022] Establish a quantitative relationship between pseudo-acoustic curves and reservoir porosity;

[0023] The acoustic wave curve is inverted to obtain the wave impedance data volume. Then, based on the quantitative relationship between the acoustic wave curve and reservoir porosity, the porosity inversion data is obtained, thereby obtaining the reservoir thickness of the target layer.

[0024] Furthermore, the reconstruction of the acoustic waveform includes the following steps:

[0025] By cross-analysis of well logging curves and reservoir response characteristics, neutron curves reflecting the reservoir are obtained;

[0026] High-frequency filtering was applied to the acoustic wave curve and low-frequency filtering was applied to the neutron curve. The filtering frequency was the dominant frequency of the seismic data in the target area, which was obtained through spectral characteristics.

[0027] By combining the low-frequency portion of the filtered acoustic wave curve with the high-frequency portion of the neutron curve, a pseudo-acoustic wave curve with acoustic wave dimensions is obtained.

[0028] Furthermore, the acoustic wave curve is filtered at a high frequency of 35Hz, and the neutron curve is filtered at a low frequency.

[0029] Furthermore, the reservoir thickness of the target layer is obtained by extracting porosity inversion data with a value greater than 2% and converting the data.

[0030] Furthermore, the single-well reservoir-to-formation ratio is obtained by using the reservoir thickness and formation thickness of known wells in the target area.

[0031] Furthermore, the difference between the reservoir ratio of the target layer and the reservoir ratio of a single well is interpolated three times to obtain gridded interpolated data.

[0032] This invention also protects a method for paleogeographic reconstruction of carbonate rocks based on reservoir-to-land ratio, comprising the following steps:

[0033] (1) Calculate the formation thickness of the target layer based on the interpretation results of the top and bottom boundaries of the target layer;

[0034] (2) Predict the reservoir thickness of the target layer by inverting the neutron curve pseudo-acoustic curve;

[0035] (3) The well-seismic fusion method is used to calculate the reservoir ratio and restore the paleomorphology of the target layer.

[0036] Specifically, the steps of this application are as follows:

[0037] (1) Calculate the formation thickness of the target layer based on the interpretation results of the top and bottom boundaries of the target layer.

[0038] Formation thickness data is a crucial parameter in oil and gas exploration and development, and its accuracy directly impacts subsequent research on the target formation. Acquiring formation thickness data involves the following steps:

[0039] Step 1: Through fine-tuning of well seismic data, determine the seismic reflection characteristics of the top and bottom boundaries of the target layer (e.g., amplitude characteristics, frequency characteristics, phase characteristics, wave group characteristics, and waveform characteristics).

[0040] The specific process for fine well-seismic calibration is as follows: ① Standardize the acoustic and density curves using methods such as baseline analysis, probability statistics, regression analysis, or field removal and smoothing filtering; ② Convert the depth-domain acoustic and density curves into time-domain logging curves; ③ Multiply the acoustic and density curves at the same time points to obtain the wave impedance curve; ④ Calculate the reflection coefficient of the corresponding interface based on the wave impedance above and below the reflection interface; ⑤ Use theoretical seismic wavelets for marker layer calibration; for specific sub-layer calibration, use the least squares method to obtain the target layer seismic wavelet based on the reflection coefficient and the well-side seismic record; ⑥ Form a synthetic record trace by convolving the time-domain reflection coefficient with the seismic wavelet; ⑦ Use the correlation coefficient method or phase surface method to perform consistency analysis between the synthetic record trace and the well-side seismic trace.

[0041] The second step is to spatially deconstruct the seismic data to obtain a three-dimensional stratigraphic model. Based on the seismic reflection characteristics of the top and bottom boundaries of the target layer, the seismic horizons of the top and bottom boundaries of the target layer are extracted from the three-dimensional model.

[0042] Spatial deconstruction methods for seismic data include: using the structural trend level of seismic interpretation as a benchmark and actual drilling stratification data as control, the resulting seismic stratigraphic interpretation data originates from both the relative seismic trend and well point data, improving the certainty of the stratigraphic data. The specific methods are: ① interpreting seismic data for stratigraphy and faults based on well-seismic calibration results; ② using a combined well-seismic approach, manually editing structural points, fault displacements, and their intersecting relationships near faults; ③ performing error checks between well-seismic stratification data and the target seismic layer, providing well corrections to achieve seamless integration between well-seismic stratification data and the target layer seismic interpretation; ④ based on the above, establishing a three-dimensional stratigraphic model based on the combined well-seismic approach.

[0043] The third step is to obtain the seismic thickness H by subtracting the seismic horizons of the top and bottom boundaries of the target layer, and then correct it using the thickness of the drilling data (H drilling thickness) to obtain the formation thickness of the target layer.

[0044] The specific process for drilling data correction is as follows: ① Statistically calculate the target formation thickness value of the drilling well and calculate the correction coefficient, i.e., R = H_drilling thickness / H_seismic thickness; ② Based on the calculated correction coefficient R at these well points, perform grid interpolation using interpolation methods such as inverse distance weighting or kriging to obtain the planar distribution of the correction coefficient; ③ Multiply the gridded data of the correction coefficient with the data obtained from the subtraction of the top and bottom seismic layers of the target formation to obtain the target formation thickness.

[0045] (2) Predict the reservoir thickness of the target layer by neutron curve pseudo-acoustic curve inversion.

[0046] Neutron curves exhibit good sensitivity to carbonate reservoirs, particularly dolomite reservoirs. To incorporate neutron curves as constraints into the seismic inversion process, they need to be converted to curves with acoustic dimensions to meet the requirements of acoustic impedance inversion theory. This mainly involves the following three steps:

[0047] Step 1: Using pseudo-acoustic curve reconstruction technology, the high-frequency part of the neutron curve, which is sensitive to the reservoir, is fitted with the low-frequency part of the acoustic curve, which reflects the lithology of the formation, to obtain a new pseudo-acoustic curve with higher resolution.

[0048] The pseudo-acoustic curve reconstruction technology is based on comprehensive research in geology, well logging, and seismic data. Targeting specific geological problems and inversion objectives, and grounded in rock physics, it selects the best logging curve from a variety of options and reconstructs a curve that reflects reservoir characteristics. The specific process is as follows: ① Standardization and normalization of logging curves; ② Through cross-sectional analysis of different logging curves and reservoir response characteristics, the sensitive logging curve (neutron curve) that best reflects the reservoir in the study area is selected; ③ Based on the spectral characteristics of seismic data in the study area, through parameter experiments at different frequencies, a 35Hz frequency (the same dominant frequency as the seismic data) is selected for high-frequency filtering of the acoustic curve and low-frequency filtering of the neutron curve; ④ Combining the low-frequency portion of the filtered acoustic curve with the high-frequency portion of the neutron curve yields a pseudo-acoustic curve with acoustic dimensions.

[0049] Step 2: Establish a new quantitative relationship between the pseudo-acoustic curve and reservoir porosity.

[0050] Step 3: Based on the new pseudo-acoustic curve, inversion is performed to obtain the acoustic impedance data volume, and according to the quantitative relationship mentioned above, the porosity inversion data is obtained. Generally, a porosity of 2% is used as the threshold value for carbonate reservoirs, and data with porosity greater than 2% are extracted and converted to obtain the reservoir thickness of the target layer.

[0051] (3) The reservoir ratio was calculated using the well-seismic fusion method to reconstruct the paleogeography of the target layer.

[0052] Step 1: Statistically analyze the reservoir thickness and formation thickness of the target layer in multiple wells in the study area, and calculate the reservoir-to-formation ratio of a single well (h_reservoir-to-formation ratio = h_target-layer reservoir thickness / h_target-layer formation thickness).

[0053] The second step is to divide the target reservoir thickness and formation thickness obtained from the seismic data to obtain the reservoir-to-land ratio. The reservoir-to-land ratio at the well point is extracted (H reservoir-to-land ratio = H target reservoir thickness / H target formation thickness), and the difference is calculated with the reservoir-to-land ratio calculated from a single well (ε = H reservoir-to-land ratio - h reservoir-to-land ratio). These differences (ε) are then interpolated using the cubic spline interpolation method to form a grid.

[0054] The third step is to fully leverage the accuracy of the reservoir ratio calculated using drilling data at the well point and the rationality of the reservoir ratio calculated using seismic data in terms of its lateral distribution trend. The reservoir ratio is calculated by organically integrating the two, that is, by merging the interpolated data of the difference grid with the reservoir ratio data obtained using seismic data to generate a new reservoir ratio contour map, thereby obtaining the paleogeography of the target layer.

[0055] Beneficial effects

[0056] This invention relates to a method for paleogeographic restoration of carbonate rocks based on reservoir-to-landform ratio. It predicts the reservoir thickness of the target layer by inverting neutron curves and pseudo-acoustic curves, and then calculates the reservoir-to-landform ratio using a well-seismic fusion method to restore the paleogeography of the target layer. This method solves the problem that directly using the residual stratum thickness to restore paleogeography can lead to inaccurate restoration, effectively improving the accuracy of paleogeographic restoration and thus increasing the success rate of exploration and development. Attached Figure Description

[0057] 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.

[0058] Figure 1 This is a flowchart illustrating the carbonate rock paleogeographic restoration technology based on the reservoir-to-land ratio in a specific embodiment.

[0059] Figure 2 This is a thickness diagram of the Carboniferous strata in Example 1 of a specific embodiment.

[0060] Figure 3 This is a bar chart of the neutron curve and pseudo-acoustic curve of a single well in Example 2 of the specific implementation method;

[0061] Figure 4 This is a plot of the pseudo-acoustic wave curve and porosity in Example 2 of the specific implementation method;

[0062] Figure 5 This is a reservoir thickness diagram from Example 2 of a specific implementation method;

[0063] Figure 6 This is a paleogeographic distribution map of Example 3 in a specific implementation method. Detailed Implementation

[0064] 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.

[0065] See the flowchart for carbonate rock paleogeographic restoration technology based on reservoir-to-land ratio. Figure 1 ,

[0066] (1) Calculate the formation thickness of the target layer based on the interpretation results of the top and bottom boundaries of the target layer;

[0067] (2) Predict the reservoir thickness of the target layer by inverting the neutron curve pseudo-acoustic curve;

[0068] (3) The well-seismic fusion method is used to calculate the reservoir ratio and restore the paleomorphology of the target layer.

[0069] The following are examples of the restoration of the Carboniferous paleogeography in the TD area, with actual drilled mines including TD1-12.

[0070] Example 1

[0071] Calculation of the thickness of the target layer:

[0072] Well-seismic fine calibration

[0073] Using a combined well-seismic calibration technique, the target layer's reflection interface is first calibrated in detail. After standardizing the well logging data, a seismic wavelet is extracted using a reflection coefficient calculation method based on wave impedance to generate a synthetic seismic record. In practice, the least squares method is used to match the actual seismic record to ensure similarity between the well-side seismic data and the synthetic record.

[0074] The specific process of well-seismic combined calibration technology includes: standardizing well logging data to convert depth-domain velocity and density curves into time-domain logging curves; multiplying the acoustic and density curves at the same time points to obtain the wave impedance curve; calculating the reflection coefficient of the corresponding interface based on the wave impedance above and below the reflection interface; using theoretical seismic wavelets for marker layer calibration; using the least squares method to obtain the target layer seismic wavelet for specific sub-layer calibration based on the reflection coefficient and well-side seismic records; forming a synthetic record trace by convolving the time-domain reflection coefficient with the seismic wavelet; and performing consistency analysis between the synthetic record trace and the well-side seismic trace using the correlation coefficient method or phase surface method.

[0075] Three-dimensional stratigraphic model establishment

[0076] Based on seismic reflection characteristics and combined with drilling data, a three-dimensional formation model is established. Within the formation model, the seismic horizons of the top and bottom boundaries of the target layer are accurately extracted, and adjustments and optimizations are made based on the results of well-seismic calibration.

[0077] The specific steps are as follows: Based on the well-seismic calibration results, the seismic data is interpreted for stratigraphy and faults; using a combined well-seismic approach, the structural points, fault displacements, and mutual cutting relationships near the faults are manually edited; errors are checked between the well-seismic data and the target layer in the seismic interpretation, and well corrections are applied to achieve seamless integration between the well-seismic data and the target layer seismic interpretation. Based on the above, a three-dimensional stratigraphic model is established using the combined well-seismic approach.

[0078] Calculation of formation thickness

[0079] The H-seismic thickness is obtained by subtracting the extracted top and bottom boundary data of the seismic horizon. Then, it is corrected using thickness data from drilling data, and correction coefficients are calculated using the inverse distance weighting method to generate a gridded distribution. Multiplying the correction coefficients by the H-seismic thickness yields the final formation thickness. See the formation thickness map. Figure 2 ;

[0080] The specific process for drilling data correction is as follows: Statistically calculate the target formation thickness value from the drilling data and then calculate the correction coefficient, i.e., R = Hdrilling thickness / Hseismic thickness. Based on the calculated correction coefficient R at these well points, perform gridded interpolation using interpolation methods such as inverse distance weighting or kriging to obtain the planar distribution of the correction coefficients. Multiply the gridded correction coefficient data with the data obtained from the subtraction of the top and bottom seismic layers of the target formation to obtain the target formation thickness.

[0081] Example 2

[0082] Predict the reservoir thickness of the target layer:

[0083] Prediction of reservoir thickness

[0084] The pseudo-acoustic curve inversion employs acoustic curve reconstruction technology, fusing the high-frequency portion of the neutron curve from a single well with the low-frequency portion of the acoustic curve to generate a pseudo-acoustic curve. See the histogram of the pseudo-acoustic curve for the neutron curve of a single well. Figure 3 For the target strata, frequency parameter optimization experiments were conducted, and 35Hz was selected as the filtering frequency to ensure high resolution of the pseudo-acoustic curve.

[0085] The pseudo-acoustic curve reconstruction technology specifically involves: standardizing and normalizing logging curves; selecting sensitive logging curves (neutron curves) that better reflect the reservoir in the study area through cross-analysis of different logging curves and reservoir response characteristics; based on the actual situation of seismic data in the study area, selecting high-frequency filtering of the acoustic curve at 35Hz and low-frequency filtering of the neutron curve through parameter experiments at different frequencies; and combining the low-frequency part of the filtered acoustic curve with the high-frequency part of the neutron curve to obtain a pseudo-acoustic curve with acoustic wave dimensions.

[0086] Reservoir porosity inversion

[0087] Based on the generated pseudo-acoustic curve, a quantitative relationship with reservoir porosity was established. See the cross-plot of the pseudo-acoustic curve and porosity. Figure 4 Porosity data were obtained using impedance retrieval techniques. Using a 2% porosity threshold as a standard, regions with porosity greater than 2% were extracted, and the reservoir thickness of the target layer was calculated. The reservoir thickness map is shown below. Figure 5 .

[0088] Example 3

[0089] Restoration of ancient landforms:

[0090] Calculation of land reserve ratio

[0091] The reservoir thickness and formation thickness of the target layer in multiple wells in the study area were statistically analyzed to calculate the reservoir-to-formation ratio of each well. Simultaneously, the reservoir thickness and formation thickness of the target layer were calculated using seismic data, and the reservoir-to-formation ratio was then divided.

[0092] Restoration of ancient landforms

[0093] By comparing the reservoir ratio of single wells and the reservoir ratio of seismic data, a gridded distribution of the reservoir ratio is adopted. Based on this, and combining the reservoir ratio information from drilling and seismic data, the paleogeographic changes of the target layer are reconstructed using the principle of sedimentary inheritance.

[0094] Specific recovery steps:

[0095] Step 1: Statistically analyze the reservoir thickness and formation thickness of the target layer in multiple wells in the study area, and calculate the reservoir-to-formation ratio of a single well (h_reservoir-to-formation ratio = h_target-layer reservoir thickness / h_target-layer formation thickness).

[0096] The second step is to divide the target reservoir thickness and formation thickness obtained from the seismic data to obtain the reservoir-to-land ratio. The reservoir-to-land ratio at the well point is extracted (H reservoir-to-land ratio = H target reservoir thickness / H target formation thickness), and the difference is calculated with the reservoir-to-land ratio calculated from a single well (ε = H reservoir-to-land ratio - h reservoir-to-land ratio). These differences (ε) are then interpolated using the cubic spline interpolation method to form a grid.

[0097] Step 3: Fully leverage the accuracy of the reservoir ratio calculated from drilling data at the well point and the rationality of the lateral distribution trend of the reservoir ratio calculated from seismic data. Calculate the reservoir ratio by organically integrating the two, specifically by merging the interpolated interpolation data with the reservoir ratio data obtained from seismic data to generate a new reservoir ratio contour map. This yields the paleogeography of the target layer. (See the paleogeography map of the target layer.) Figure 6 ,

[0098] Current technology generally suggests that areas with high paleomorphic elevations have thicker reservoirs, which are formed by... Figure 2 It is evident that the formation thickness of TD13 is greater than that of TD12; however, from... Figure 5 It is evident that the actual drilled reservoir thickness of TD13 is smaller than that of TD12, while referring to... Figure 6 It is evident that the paleogeography of TD13 is lower than that of TD12, and the reservoir thickness is smaller. Therefore, the paleogeography restoration method provided by this invention is closer to actual drilling, effectively improving the accuracy of paleogeography restoration.

Claims

1. A method for paleogeographic reconstruction of carbonate rocks based on reservoir-to-land ratio, comprising the following steps: Calculate the formation thickness of the target layer, predict the reservoir thickness of the target layer, and obtain the reservoir-to-land ratio of the target layer; The difference between the reservoir ratio of the target layer and the reservoir ratio of a single well is obtained, and the difference is then interpolated by gridding to obtain gridded interpolated data of the difference. The interpolated data of the difference gridded interpolation is merged with the reservoir ratio data of the target layer to obtain the paleogeography of the target layer.

2. The method for restoring paleogeography of carbonate rocks according to claim 1, characterized in that, The calculation of the formation thickness of the target layer includes the following steps: Through fine-tuning of well seismic data, the seismic reflection characteristics of the top and bottom boundaries of the target layer are determined; The seismic reflection characteristics are spatially deconstructed to obtain a three-dimensional stratigraphic model. The seismic horizons of the top and bottom boundaries of the target layer are obtained from the three-dimensional stratigraphic model. The seismic thickness is obtained based on the seismic horizons of the top and bottom boundaries of the target layer. The seismic thickness is corrected, and the thickness of the target layer is obtained after correction.

3. The method for restoring paleogeography of carbonate rocks according to claim 2, characterized in that, Well-seismic fine calibration includes the following steps: The acoustic and density curves are standardized; the depth-domain acoustic and density curves are converted into time-domain logging curves; the acoustic and density curves at the same time point are multiplied to obtain the wave impedance curve; the reflection coefficient of the corresponding interface is calculated based on the wave impedance above and below the reflection interface; theoretical seismic wavelets are used for marker layer calibration; for specific sub-layer calibration, the target layer seismic wavelet is obtained using the least squares method based on the reflection coefficient and the well-side seismic record; a synthetic record is formed by convolving the time-domain reflection coefficient with the seismic wavelet; the consistency analysis between the synthetic record and the well-side seismic record is performed using the correlation coefficient method or phase surface method to complete the fine well-seismic calibration.

4. The method for restoring paleogeography of carbonate rocks according to claim 3, characterized in that, The calibration includes the following steps: Calculate the correction factor based on the formation thickness and seismic thickness of the target layer already drilled; Based on the correction coefficients, gridded interpolation is performed to obtain gridded data of the correction coefficients; The thickness of the target layer is obtained based on the gridded data of the correction coefficient and the seismic horizons at the top and bottom of the target layer.

5. The method for restoring paleogeography of carbonate rocks according to claim 1, characterized in that, Predicting the reservoir thickness of the target layer includes the following steps: By reconstructing the neutron curve and the acoustic curve, a pseudo-acoustic curve is obtained; Establish a quantitative relationship between pseudo-acoustic curves and reservoir porosity; The acoustic wave curve is inverted to obtain the wave impedance data volume. Then, based on the quantitative relationship between the acoustic wave curve and reservoir porosity, the porosity inversion data is obtained, thereby obtaining the reservoir thickness of the target layer.

6. The method for restoring paleogeography of carbonate rocks according to claim 5, characterized in that, Reconstruction of acoustic waveforms includes the following steps: By cross-analysis of well logging curves and reservoir response characteristics, neutron curves reflecting the reservoir are obtained; The acoustic wave curve and neutron curve are filtered, and the filtering frequency is the dominant frequency of the seismic data in the target area. By combining the low-frequency portion of the filtered acoustic wave curve with the high-frequency portion of the neutron curve, a pseudo-acoustic wave curve with acoustic wave dimensions is obtained.

7. The method for restoring paleogeography of carbonate rocks according to claim 6, characterized in that, The dominant frequency of seismic data in the target area is obtained through the spectral characteristics of the seismic data.

8. The method for restoring paleogeography of carbonate rocks according to claim 5, characterized in that, Extract data with a porosity inversion greater than 2% to obtain the reservoir thickness of the target layer.

9. The method for restoring paleogeography of carbonate rocks according to claim 1, characterized in that, The single-well reservoir-to-formation ratio is obtained by using the reservoir thickness and formation thickness of known wells drilled in the target area.

10. The method for restoring paleogeography of carbonate rocks according to claim 1, characterized in that, The difference between the reservoir ratio of the target layer and the reservoir ratio of a single well is interpolated three times to obtain gridded interpolated data.

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