摘要
This research on the attenuation features of intensity in the Yunnan region has been conducted by using intensity isoseismals of 127 earthquakes, and the following three conclusions have been put forward: (1) The average ratio value of long axis to short axis of innermost isoseismals in the Yunnan region is larger than that of eastern China and smaller than that of western China. The velocity of intensity attenuation varies in different directions; (2) The zoning feature of intensity attenuation in the Yunnan region is obvious; (3) In Northwest China and North China, the ratios of long axis to short axis of low magnitude isoseismals are larger than those of high magnitude ones. Compared with that phenomenon, the ratios in the Yunnan region are more complicated. Finally, some relevant questions are discussed.
This research on the attenuation features of intensity in the Yunnan region has been conducted by using intensity isoseismals of 127 earthquakes, and the following three conclusions have been put forward: (1) The average ratio value of long axis to short axis of innermost isoseismals in the Yunnan region is larger than that of eastern China and smaller than that of western China. The velocity of intensity attenuation varies in different directions; (2) The zoning feature of intensity attenuation in the Yunnan region is obvious; (3) In Northwest China and North China, the ratios of long axis to short axis of low magnitude isoseismals are larger than those of high magnitude ones. Compared with that phenomenon, the ratios in the Yunnan region are more complicated. Finally, some relevant questions are discussed.
基金
Sortoftheproject:fundedbytheNaturalScientificFoundationofYunnanProvince (2 0 0 0D0 0 2 8Q)
China .
