阅读说明：本技术 一种利用三维地震恢复相对微古地貌的工业化流程 (Industrialized process for recovering relatively micro ancient landform by using three-dimensional earthquake ) 是由 张宪国 张涛 吴啸啸 刘杰 刘华峰 黄德榕 刘玉从 段冬平 黄鑫 于 2020-06-08 设计创作，主要内容包括：本发明公开了一种利用三维地震恢复相对微古地貌的工业化流程,具体方法是,利用地层顶界面和底界面的地震解释求取地层厚度,利用井点的测井信息对地震解释得到的地层厚度进行井点校正,利用地震倾角属性分析得到地层倾角余弦值,利用地层顶面和底面的倾角余弦平均值与井点校正后的地层厚度求取地层真厚度分布,上述流程得到的地层真厚度可以反映目的层沉积时期的相对微古地貌形态。本发明为少井地区基于三维地震资料恢复微古地貌提供了一种简单、合理而有效的方法。(The invention discloses an industrialized process for recovering relatively micro-ancient landforms by using a three-dimensional earthquake, which comprises the steps of solving the thickness of a stratum by using earthquake interpretation of a top interface and a bottom interface of the stratum, carrying out well point correction on the thickness of the stratum obtained by the earthquake interpretation by using well logging information of well points, obtaining a cosine value of a dip angle of the stratum by using earthquake dip angle attribute analysis, solving the true thickness distribution of the stratum by using the cosine average value of the dip angle of the top surface and the bottom surface of the stratum and the thickness of the stratum obtained by the well point correction, wherein the true thickness of the stratum obtained by the process can reflect the relatively micro-ancient landform form of a target stratum in a deposition period. The invention provides a simple, reasonable and effective method for recovering the micro ancient landform based on the three-dimensional seismic data in the area with few wells.)

1. An industrial process for recovering a relatively micro ancient landform by using a three-dimensional earthquake is characterized by comprising the following steps of:

step (1): on the three-dimensional seismic data, a well-seismic combined seismic data interpretation method is utilized to respectively obtain a data grid T of the top surface depth of the target stratum_topAnd the data grid T of the depth of the bottom surface_bot；

Step (2): subtracting the bottom surface and the top surface of the target stratum to obtain the thickness data grid T of the target stratum_h；

Wherein, the calculation formula in the step (2) is T_h＝T_bot-T_top；

And (3): selecting any well A in the research area and forming a grid T in the thickness of the stratum_hReading the thickness h of the stratum obtained by seismic interpretation at the well A_tObtaining the stratum thickness h at the well A by using the logging curve data of the well A_lSubtracting the two to obtain the error D of the seismic interpretation result at the well point A_A；

Wherein the calculation formula in the step (3) is D_A＝h_l-h_t；

And (4): obtaining each well point of the research area by using the method in the step (3)The error of the stratum thickness is calculated, and the data points are interpolated and extrapolated to obtain an error grid T covering the research area_d；

And (5): mixing T of step (2)_hWith T of step (4)_dAdding to obtain the stratum thickness data grid T after well seismic correction_hc；

Wherein the calculation formula in the step (5) is T_hc＝T_h+T_d；

And (6): calculating seismic dip data grid T of top surface of target layer by utilizing three-dimensional seismic attribute analysis_datCalculating cosine value of each point on the grid to obtain a grid T of inclination angle cosine value of the top surface of the target layer_cost；

And (7): calculating seismic dip data grid T of target layer bottom surface by utilizing three-dimensional seismic attribute analysis_dabCalculating cosine value of each point on the grid to obtain a grid T of inclination angle cosine value of the bottom surface of the target layer_cosb；

And (8): carrying out arithmetic averaging on the top surface and bottom surface stratum inclination angle cosine value grids of the target layer respectively obtained in the step (6) and the step (7) to obtain an average stratum inclination angle cosine value grid T of the target layer of the research area_cosave；

Wherein the calculation formula in the step (8) is T_cosave＝(T_cost+T_cosb)/2；

And (9): multiplying the stratum thickness data grid obtained after the well seismic correction in the step (5) with the average stratum inclination angle cosine value grid of the target layer obtained in the step (8) to obtain a target stratum true thickness data grid T_hr；

Wherein the calculation formula in the step (9) is T_hr＝T_hc×T_cosave；

Step (10): utilizing the target stratum true thickness data grid T obtained in the step (9)_hrContour maps were made as the relative paleotopographic morphology during the deposition period of the target layer.

Technical Field

The invention relates to the technical field of exploration and development of oil and gas reservoirs, in particular to an industrial process for recovering relatively micro-ancient landforms by using three-dimensional seismic data.

Background

The ancient landform is an important factor for controlling the deposition of the oil and gas reservoir, and can control the development type, the spreading range, the internal structure and the sedimentary facies mode of the reservoir. Ancient landform research is an important content in reservoir sedimentary facies research. For a long time, scholars at home and abroad continuously research the restoration method of the ancient landform, and a series of ancient landform restoration methods are formed.

In regional paleotopographic restoration, factors mainly considered include changes in formation morphology and changes in formation thickness, and paleotopographic restoration mainly develops around restoration of these two factors. For the recovery of the change in the form of the structure, on the one hand, the recovery of the amount of sedimentation of the structure and on the other hand, the recovery of the amount of horizontal slip. The method mainly comprises three aspects of carrying out work on the recovery of stratum thickness change, namely, carrying out compaction correction to solve the stratum thickness change caused by differential compaction, solving the stratum thickness change caused by differential deposition through the recovery of ancient water depth, and carrying out the recovery of denudation amount to solve the stratum thickness change formed by denudation difference.

Aiming at the ancient landform restoration problems, the conventional methods have four major categories, namely a residual thickness and compensation thickness impression method, the method has the idea of restoring the stratum denudation amount and the original thickness and reflecting the ancient landform form by utilizing the ancient thickness; the stratum back-stripping method is a method for recovering the original landform shape of a basin in a certain period of basin development by quantifying the sedimentation amount of the basin; thirdly, a sedimentology analysis method, wherein the method combines various sedimentology analysis means such as formation analysis, ancient tectonic developmental characteristics, ancient flow analysis and the like to recover ancient landforms; and fourthly, a sequence stratigraphy recovery method, which selects an isochronous surface as a reference surface to recover the original ancient landform morphology of the underlying stratum before deposition.

For the restoration of small-scale micro-ancient landforms, the currently common methods have three major categories, wherein the first category is the identification of ancient valleys and co-deposition faults; the second major category is the deposition micro-inversion method; the third category is the characterization of sand microstructure by using dense well pattern data, and the method is mainly suitable for areas with dense well points. For areas with few well points, such as offshore oil fields and onshore oil field exploration stages, an effective method and technology for recovering micro-ancient landforms by using seismic data are lacked. The invention researches and develops an industrial process for recovering the micro-ancient landform by using seismic data, aiming at the defects of the existing method for recovering the micro-ancient landform of a few well zones by using the seismic data.

Disclosure of Invention

The invention provides an industrialized process for recovering a relatively micro-ancient landform by using three-dimensional seismic data, which comprises the following steps:

step (1): on the three-dimensional seismic data, a well-seismic combined seismic data interpretation method is utilized to respectively obtain a data grid T of the top surface depth of the target stratum_topAnd the data grid T of the depth of the bottom surface_bot；

Step (2): subtracting the bottom surface and the top surface of the target stratum to obtain the thickness data grid T of the target stratum_h；

The calculation formula in the step (2) is T_h＝T_bot-T_top；

And (3): selecting any well A in the research area and forming a grid T in the thickness of the stratum_hReading the thickness h of the stratum obtained by seismic interpretation at the well A_tObtaining the stratum thickness h at the well A by using the logging curve data of the well A_lSubtracting the two to obtain the error D of the seismic interpretation result at the well point A_A；

The calculation formula in the step (3) is D_A＝h_l-h_t；

And (4): obtaining stratum thickness errors at each well point of the research area by using the method in the step (3), and carrying out interpolation and extrapolation calculation on the data points to obtain an error grid T covering the research area_d；

And (5): mixing T of step (2)_hWith T of step (4)_dAdding to obtain the stratum thickness data grid T after well seismic correction_hc；

The calculation formula in the step (5) is T_hc＝T_h+T_d；

And (6): calculating seismic dip data grid T of top surface of target layer by utilizing three-dimensional seismic attribute analysis_datCalculating cosine value of each point on the grid to obtain a grid T of inclination angle cosine value of the top surface of the target layer_cost；

And (7): calculating seismic dip data grid T of target layer bottom surface by utilizing three-dimensional seismic attribute analysis_dabCalculating cosine value of each point on the grid to obtain a grid T of inclination angle cosine value of the bottom surface of the target layer_cosb；

And (8): carrying out arithmetic averaging on the top surface and bottom surface stratum inclination angle cosine value grids of the target layer respectively obtained in the step (6) and the step (7) to obtain an average stratum inclination angle cosine value grid T of the target layer of the research area_cosave；

The calculation formula in the step (8) is T_cosave＝(T_cost+T_cosb)/2；

And (9): multiplying the stratum thickness data grid obtained after the well seismic correction in the step (5) with the average stratum inclination angle cosine value grid of the target layer obtained in the step (8) to obtain a target stratum true thickness data grid T_hr；

The calculation formula in the step (9) is T_hr＝T_hc×T_cosave；

Step (10): utilizing the target stratum true thickness data grid T obtained in the step (9)_hrContour maps were made as the relative paleotopographic morphology during the deposition period of the target layer.

Detailed Description

The method is implemented according to the steps in the above invention content, and specifically comprises the following steps:

(1) on the three-dimensional seismic data, a well-seismic combined seismic data interpretation method is utilized to respectively obtain a data grid T of the top surface depth of the target stratum_topAnd the data grid T of the depth of the bottom surface_bot；

(2) Subtracting the bottom surface and the top surface of the target stratum to obtain the thickness data grid T of the target stratum_hWherein T is_h＝T_bot-T_top；

(3) Selecting any well A in the research area and forming a grid T in the thickness of the stratum_hReading the thickness h of the stratum obtained by seismic interpretation at the well A_tObtaining the stratum thickness h at the well A by using the logging curve data of the well A_lSubtracting the two to obtain the error D of the seismic interpretation result at the well point A_AWherein D is_A＝h_l-h_t；

(4) Carrying out interpolation and extrapolation calculation on the stratum thickness error at each well point of the research area to obtain an error grid T covering the research area_d；

(5) Mesh T_hAnd grid T_dAdding to obtain the stratum thickness data grid T after well seismic correction_hcWherein T is_hc＝T_h+T_d；

(6) Calculating seismic dip data grid T of top surface of target layer by utilizing three-dimensional seismic attribute analysis_datCalculating cosine value of each point on the grid to obtain a grid T of inclination angle cosine value of the top surface of the target layer_cost；

(7) Calculating seismic dip data grid T of target layer bottom surface by utilizing three-dimensional seismic attribute analysis_dabCalculating cosine value of each point on the grid to obtain a grid T of inclination angle cosine value of the bottom surface of the target layer_cosb；

(8) Calculating the average formation dip cosine value grid T of the target layer of the research area_cosaveWherein T is_cosave＝(T_cost+T_cosb)/2；

(9) Mesh T_hcAnd grid T_cosaveMultiplying to obtain the target stratum true thickness data grid T_hrWherein T is_hr＝T_hc×T_cosave；

(10) Utilizing a target formation true thickness data grid T_hrContour maps were made as the relatively micro-ancient topographic morphology of the deposition period of the target layer.