TY  - JOUR
PY  - 2006//
TI  - On Temporal and Spatial Distribution of Seismic Apparent Stresses in Yunnan Area
JO  - Acta seismologica sinica. English edition
A1  - Qin, JZ
A1  - Qian, XD
SP  - 233
EP  - 242
VL  - 19
IS  - 3
N2  - The method of radiation energy (E sub-R) of the earthquake wave measured by the peak velocity (r-v) of the ground motion is applied to a detailed study on the temporal and spatial distribution of the seismic apparent stresses (sigma sub-a) for the moderate and small earthquakes and two aftershock sequences in Yunnan area. The results show that there exists an obvious non-homogeneity for the seismic apparent stresses in the spatial distribution. The concentrated regions of the high apparent stresses are related to the active places of the moderate and small earthquakes. Before the Dayao M = 6.2 earthquake, there was a period in which the apparent stresses were high and the value was 5 times of the average value, 0.25 MPa. The relatively high values of apparent stresses distribute around the epicentral area of the major shock and nearby. It indicates that the variation characteristics of the apparent stresses can be taken as a new kind of criterion for the earthquake-risk forecast. Usually the ratio of the apparent stresses of the aftershock sequence sigma sub-aA to the ones sigma sub-aM of main shock is less than 1.0.     <p>Language: en</p>
LA  - en
SN  - 1000-9116
UR  - http://dx.doi.org/
ID  - ref1
ER  -