ISSN:
1420-9136
Keywords:
Microseismicity
;
source parameter scaling
;
seismic efficiency
;
principal stresses
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract Source parameter scaling relations are examined for microseismic events (−2.4≤M≤−0.3) occurring within higyly and moderately stressed and fractured rock masses at Strathcona mine, Sudbury, Canada. Insight into scaling is provided by waveform complexities, calculated rupture velocities, and maximum shear stresses based onin situ and numerical modelling data. The importance of normal stress on the failure process is also considered. Our results show that a strong dependence exists between stress release and seismic moment. An observed positive scaling in excess stress release (Δσ/2−σ a ) is consistent with the concept of overshoot. Rupture velocities ranging from 0.2 to 0.5β and waveform complexities less than 1.5 suggested that overshoot was related to healing behind a slowly advancing rupture front. Scaling in seismic efficiency paralleled that in apparent stress, implying that seismic stress release estimates are quasi-independent of the maximum shear stress. High levels of normal stress further supported the importance of high resisting stress in the observed overshoot behaviour and its role in the failure process.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00877486
