CN-121995455-A - Fluid identification method, device and medium based on energy difference

CN121995455ACN 121995455 ACN121995455 ACN 121995455ACN-121995455-A

Abstract

The invention provides a fluid identification method, device and medium based on energy difference, and belongs to the field of geophysical exploration. The method comprises the steps of S100, inputting a CRP gather and average speed data V stk , S200, extracting an angle gather according to the input CRP gather and the average speed data V stk , S300, extracting partial superposition data bodies of three angles of large, medium and small, S400, calculating a time channel gather of the three angles, S500, extracting discrete energy bodies of the low frequency band and the high frequency band of the partial superposition data of the three angles, and S600, and extracting energy difference attribute data bodies. The method considers the difference between the near and far channels after the stratum contains oil gas and the change between the low-frequency band and the high-frequency band attributes, extracts the energy or the attributes of different incident angles and different frequency bands based on the angle part superposition data, and can be used for carrying out seismic fluid identification research.

Inventors

CHEN KE
WANG PENGYAN
Xiao Renrui
XIANG KUN
WANG CAIYUN

Assignees

中国石油化工股份有限公司
中石化石油物探技术研究院有限公司

Dates

Publication Date: 20260508
Application Date: 20241107

Claims (10)

1. A method of fluid identification based on energy differences, comprising: s100, inputting CRP gathers and average speed data V stk ; S200, extracting an angle gather according to the input CRP gather and the average speed data V stk ; s300, extracting partial superposition data bodies with large, medium and small angles; S400, calculating time channel sets of three angles; S500, extracting discrete energy bodies of the low frequency band and the high frequency band of the data overlapped by the three angle parts; S600, extracting the energy difference attribute data volume.
2. The method of claim 1, wherein S200, extracting the angle gather based on the entered CRP gather and the average speed, comprises: For the incoming CRP gather and average velocity data V stk , an angle gather ANGGATHER is calculated, specifically using the following formula to extract the angle gather: Where θ is the angle value, x is the offset, V stk is the average speed data, and t 0 is the current time of travel.
3. The method of claim 1, wherein S400, the computing the time-channel set for the three angles comprises: And respectively carrying out time-frequency decomposition on the partial superposition data bodies PS min 、PS mid and PS max under three angles by using a high-precision time-frequency analysis method to respectively obtain time channel sets TFG min 、TFG mid and TFG max .
4. The method according to claim 1, wherein S500, the extracting discrete energy bodies of the low frequency band and the high frequency band of the three angle partial overlap data body comprises: defining frequency ranges of a low frequency band and a high frequency band; according to the frequency ranges of the defined low frequency band and the high frequency band, discrete energy bodies Dis min-low 、Dis min-high 、Dis mid-low 、Dis mid-high 、Dis max-low and Dis max-high of the low frequency band and the high frequency band of the three angle part superposition data bodies are extracted; wherein, dis min-low is a small-angle low-frequency discrete energy body, dis min-high is a small-angle high-frequency discrete energy body, dis mid-low is a medium-angle low-frequency discrete energy body, dis mid-high is a medium-angle high-frequency discrete energy body, dis max-low is a large-angle low-frequency discrete energy body, and Dis max-high is a large-angle high-frequency discrete energy body.
5. The method of claim 4, wherein S600, extracting the energy difference attribute data volume, comprises: The energy difference attribute of each position of the three-dimensional space is calculated according to the following formula: EnVar (i,j,k) ＝0.5*[(Dis(i,j,k) min-high -Dis(i,j,k) min-low )/(Dis(i,j,k) mid-high -Dis(i,j,k) mid-low )] -0.5*[(Dis(i,j,k) mid-high -Dis(i,j,k) mid-low )/(Dis(i,j,k) max-high -Dis(i,j,k) max-low )] Where (i, j, k) is a position coordinate in three-dimensional space.
6. A fluid identification device based on energy differences, comprising: an input unit for inputting CRP gather and average speed data V stk ; The angle gather extraction unit is used for extracting the angle gather according to the input CRP gather and the average speed data V stk ; a partial superimposed data volume extraction unit for extracting partial superimposed data volumes of three angles of large, medium and small; a time channel set calculating unit for calculating time channel sets of three angles; The discrete energy body extraction unit is used for extracting discrete energy bodies of the low frequency band and the high frequency band of the three-angle partial superposition data; And the energy difference attribute extraction unit is used for extracting the energy difference attribute data volume.
7. The apparatus according to claim 6, wherein the angle gather extraction unit performs in particular the following operations: For the incoming CRP gather and average velocity data V stk , an angle gather ANGGATHER is calculated, specifically using the following formula to extract the angle gather: Where θ is the angle value, x is the offset, V stk is the average speed data, and t 0 is the current time of travel.
8. The apparatus of claim 6, wherein the time channel set calculation unit specifically performs the following operations: And respectively carrying out time-frequency decomposition on the partial superposition data bodies PS min 、PS mid and PS max under three angles by using a high-precision time-frequency analysis method to respectively obtain time channel sets TFG min 、TFG mid and TFG max .
9. The apparatus according to claim 6, wherein the energy difference attribute extraction unit specifically performs the following operations: The energy difference attribute of each position of the three-dimensional space is calculated according to the following formula: EnVar (i,j,k) ＝0.5*[(Dis(i,j,k) min-high -Dis(i,j,k) min-low )/(Dis(i,j,k) mid-high -Dis(i,j,k) mid-low )] -0.5*[(Dis(i,j,k) mid-high -Dis(i,j,k) mid-low )/(Dis(i,j,k) max-high -Dis(i,j,k) max-low )] Where (i, j, k) is a position coordinate in three-dimensional space.
10. A computer-readable storage medium storing at least one program executable by a computer, the at least one program, when executed by the computer, causing the computer to perform the steps in the energy-difference-based fluid identification method of any one of claims 1-5.

Description

Fluid identification method, device and medium based on energy difference Technical Field The invention belongs to the field of geophysical exploration, and particularly relates to a fluid identification method, device and medium based on energy difference. Background The seismic acquisition is to utilize the vibration of an artificial seismic source to generate seismic wavelets, the seismic wavelets can generate transmission and reflection when encountering a stratum impedance difference interface when propagating to the underground, the seismic signals from the underground are received through detectors arranged on the ground or in a well, and the CRP gather after offset homing or the seismic data after superposition can be obtained through processing and imaging technologies. The seismic section contains abundant amplitude and travel time information, and the energy attenuation caused by the seismic waves in the propagation process is hidden in the seismic signals, the seismic wave attenuation is classified into two types, namely the attenuation related to the propagation characteristics of the seismic waves, the shallow attenuation is larger and deeper, the intrinsic attenuation related to a propagation medium, such as absorption attenuation caused by passing through an oil-gas-containing stratum, and the characteristic of the second attenuation is utilized for detecting the oil-gas content of the stratum. Various fluid identification methods are researched by scientific researchers according to attenuation characteristics of seismic waves after the seismic waves pass through an oil-gas-containing stratum, and the fluid identification methods are mainly divided into two categories, namely prestack and poststack. The method can be used for detecting the fluid of different types of reservoirs based on the attributes such as desserts, absorption coefficients, attenuation gradients, highlights, frequency attenuation or low-frequency companion shadows and the like extracted from post-stack seismic data, and the post-stack fluid identification technology is simple, convenient and quick to apply, but the application effect is greatly influenced by the types of the reservoirs. The technology such as AVO attribute analysis, pre-stack elastic parameter inversion and frequency-dependent AVO inversion based on pre-stack data can also be used for fluid identification, parameters extracted by the pre-stack fluid identification technology are more abundant, and the capability of solving practical problems is stronger, but the pre-stack inversion technology has complex flow, involves the steps of seismic horizon calibration, angle wavelet extraction, petrophysical modeling, seismic inversion and the like, and has the advantages of large calculated amount, long application period and high technical threshold. Disclosure of Invention The invention aims to solve the problems in the prior art, and provides a fluid identification method, a device and a medium based on energy difference, wherein the attribute for fluid identification is constructed by fully utilizing the energy difference of different incidence angles and different frequency bands based on angle part superposition data of incidence angles, the calculation step is simple and convenient, and the detection capability of fluid identification can be improved. The invention is realized by the following technical scheme: in a first aspect of the present invention, there is provided a fluid identification method based on energy differences, comprising: s100, inputting CRP gathers and average speed data V stk; S200, extracting an angle gather according to the input CRP gather and the average speed data V stk; s300, extracting partial superposition data bodies with large, medium and small angles; S400, calculating time channel sets of three angles; S500, extracting discrete energy bodies of the low frequency band and the high frequency band of the data overlapped by the three angle parts; S600, extracting the energy difference attribute data volume. The invention further improves that: s200, extracting an angle gather according to the input CRP gather and the average speed, wherein the specific operation comprises the following steps: For the incoming CRP gather and average velocity data V stk, an angle gather ANGGATHER is calculated, specifically using the following formula to extract the angle gather: Where θ is the angle value, x is the offset, V stk is the average speed data, and t 0 is the current time of travel. The invention further improves that: S400, calculating a time channel set of three angles, wherein the specific operation comprises the following steps: And respectively carrying out time-frequency decomposition on the partial superposition data bodies PS min、PSmid and PS max under three angles by using a high-precision time-frequency analysis method to respectively obtain time channel sets TFG min、TFGmid and TFG max. The invention further improves that: