-
公开(公告)号:JPH02256791A
公开(公告)日:1990-10-17
申请号:JP31048189
申请日:1989-11-29
申请人: GAS RES INST
发明人: KENISU DEII MAARAA
摘要: PURPOSE: To improve reliability of a fracture zone dimension and shape estimating means by determining a method for analyzing a seismic wave motion in the each depth of a well detected during a prescribed time after stopping the pressurization of the fracture water pressure of the well. CONSTITUTION: A horizontally two-directional and vertically directional three- component motion sensor sonde 13 is provided in a record station 22 of a well casing 10 passing through a fracture zone 11. Secondly, a wave motion before the fracture is detected at series of positions exceeding a fracture design vertical range so as to determine a reference. Thirdly, the wave motion during an unstable time after stopping the pressurization of the fracture water pressure is detected in the same position. After eliminating the noise not contributing to the fracture, an average background level of vertical and horizontal components is determined, its ratio is found, and the presence/absence of fracture is judged using it as a parameter. The height and the depth of the fracture can be thus determined using standard facility technology at low cost and high reliability.