Fitting of Acceleration Peak Attenuation With Six area Model for Wenchuan 8.0 Magnitude Earthquake
YANG Fan and LUO Qi feng
DOI:10.11835/j.issn.1674-4764.2010.05.006
Received March 10, 2010,Revised , Accepted , Available online July 01, 2015
Volume ,2010,Pages 29-34
- Abstract
At present, euqi distance circle model is generally used for directly fitting acceleration peak attenuation. Epicenter distance or focal distance is the only coordinate statistical parameter of seismic station. For large earthquake with a long fault, the iso seismical curve of euqi distance exists serious deviation from realistic iso seismal curve. Six area model was addressed to correct the deviation. With the model, seismic station was divided into six areas by two cut lines of coincided with fault and four cut lines perpendicular to fault. The acceleration peak attenuation curve along cut lines was fitted to analyse the relationship between attenuation curve and area seismic station. Take Wenchuan earthquake for an instance, the accuracy of the model is much higher than that of euqi distance circle model and a little higher than that of four area elliptical model. And the model is more accurate than four area elliptical model in reflecting hanging and foot wall effect and direction effect.