On Site Mapping of Microseismicity at Cooper Basin, Australia Hdr Project by the Japanese Team

A large scale hydraulic injection was conducted at the Australian Hot Dry Rock site in November and December, 2003 in order to develop a commercial size underground heat exchanger. A Japanese seismic team set up the seismic network and data acquisition system, and carried out microseismic monitoring during the period in co-operation with the Australian teams. On-site analysis was done as an almost real-time process by means of auto and manual time picking. Information such as 3D distribution of events, time-spatial growth of seismicity, and roughly estimated magnitude were reported simultaneously. More than 11,000 events were located as the result of the on-site mapping. The information from microseismicity was practically used for planning and determination of the appropriate hydraulic pumping program, and will be critical to the determination of the location for the second well.