TY  - JOUR
ID  - epos1798
UR  - http://doi.org/10.1785/0120040170
IS  - 3
A1  - Oye, Volker
A1  - Bungum, Hilmar
A1  - Roth, Michael
Y1  - 2005/06//
N2  - To investigate source-scaling relations for small earthquakes (Mw ?1.8 to 1.2) we have determined source parameters for numerous events (?1500) from the 1400-m-deep Pyhäsalmi ore mine in Finland. In addition to a spectral integration approach, we have fitted Brune, Boatwright, and Haskell spectral-shape models to the observed spectra and investigated attenuation influences. Of three different constant Q models (200, 350, and 800), a Q of 350 in combination with the Brune spectral model satisfied the data best. We have also investigated the frequency dependence of Q using the spectral decay method and found that Q increases with frequency. For selected events from two distinct clusters, we compared source parameters derived from constant Q models with source parameters using the multiple empirical Green?s function (megf) approach. By using constant Q models, the apparent stress seems to increase with magnitude, whereas results based on the megf approach indicate constant apparent stress with magnitude. In comparison with results from other studies that cover a larger-magnitude scale, we find apparent stresses that are about 1 to 2 orders of magnitude smaller than most of those. A modified M0 ? fc?(3 + ?) scaling relation allows for increasing apparent stress with magnitude and can hence combine this study?s results with apparent stresses found for large earthquakes. However, within the limited-magnitude range of our data, apparent stresses seem constant.
PB  - Seismological Society of America
JF  - Bulletin of the Seismological Society of America
VL  - 95
SN  - 0037-1106
TI  - Source Parameters and Scaling Relations for Mining-Related Seismicity within the Pyhasalmi Ore Mine, Finland
SP  - 1011
AV  - none
EP  - 1026
ER  -