关键词: 水力压裂, 微地震监测, 微地震事件, 初至拾取, 定位, 裂缝

Abstract: Unconventional oil and gas reserves, such as tight sandstone oil and gas, coalbed methane and shale gas, are becoming an important area for reserve growth at the present time and in the future. Hydraulic fracturing is an indispensible technology for unconventional oil and gas development. Microseismic monitoring can provide dynamic distribution of fractural network at real time while guiding hydraulic fracturing operation and appraising fracturing results. GeoEast-ESP bring about integration of acquisition, processing and interpretation of borehole and surface microseismic data during real-time monitoring, making technological breakthroughs in optimization of velocity model, noise suppression and real-time positioning. It shows the technology for noise attenuation and signal enhancement based on low signal-noise ratio microseismic signals and increases the on-field timeliness of automatic first arrival picking and positioning in microseismic events. It can combine the real-time monitoring results with fracturing curves as well as logging and seismic data for integrated interpretation. The positioning time under borehole monitoring is less than three seconds while the time under surface monitoring is less than 30 seconds. The on-field monitoring results can be submitted within 24 hours with the positioning error limited to less than 10 meters. This software package has been used in hydraulic fracturing operations for more than 200 wells at 17 oil and gas fields in China, providing technological support for adjustment of operational parameters and optimization of fracturing plans.

Key words: hydraulic fracturing, microseismic monitoring, microseismic event, first arrival picking, positioning, fractures