Scaling of Reduced Energy for Deep-Focus Earthquakes and its Apparent Depth Dependence

doi:10.7523/j.issn.2095-6134.2005.3.004

Abstract

Abstract:

The ratio of radiated energy over seismic moment, or the so called reduced energy, is studied for global deep-focus earthquakes deeper than 70km using the scalar seismic moment in the Harvard CMT catalogue and the radiated energy estimated by NEIL from January 1987 to December 2001. The scaling of reduced energy versus seismic moment is obtained for different depth ranges, respectively. It is olxerved that for earthquakes with depths between 70km and 400km, reduced energy decreases with seismic moment,while for earthquakes with depths beyond 400km, reduced energy increases with seismic moment. This characteristic is apparently different from that of shallow earthquakes.

Key words: deep-focus earthquakes, reduced energy, radiated energy, seismic moment, apparent stress

CLC Number:

P315

WU Zhong-Liang . Scaling of Reduced Energy for Deep-Focus Earthquakes and its Apparent Depth Dependence[J]. , 2005, 22(3): 279-285.

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