Method for detecting reservoir velocity change through inter-well time-lapse earthquake

• Main Authors: ZHANG FENGJIAO, GONG XIANGBO, HAN LIGUO, XU ZHUO
• Format: Patent
• Language: Chinese; English
• Published: 04.04.2023
• Subjects: DETECTING MASSES OR OBJECTS; GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; MEASURING; PHYSICS; TESTING

The invention provides an inter-well time-lapse seismic reservoir velocity change detection method, which comprises the following steps of: performing conventional data processing, wave field separation processing and time-lapse seismic data processing on time-lapse seismic data, designing a sliding time window, and calculating a time-lapse cross correlation coefficient of a time-lapse upgoing wave seismic channel set in the sliding time window; obtaining the delay time when the time shift cross correlation coefficient reaches the maximum value; calculating the relative speed change of each time window; then obtaining an average speed change; then, calculating the time-shifted uplink wave field and the time-shifted downlink wave field channel by channel, and drawing a curve that the speed changes along with the depth changes; and delimiting the depth range of reservoir velocity change through comprehensive comparison. According to the method, the tiny change of the speed of the underground reservoir can be ef