关键词: 鲜水河断裂, 断层泥, 显微构造, 分形, 断层分段

Abstract: The Xianshuihe fault zone is a well known active fault located at the north eastern boundary of the Tibetan plate. The micro texture and microstructures of fault gouge, the eroded micro texture and microstructures on the surface of quartz fragments from the fault zone are measured by Scanning Electron Microscope. The results of statistics and analysis show that the fault zone has experienced the intense oriented stress field and displays the stick slip movement mode. Its activity was still continuing from late Pleistocene to Holocene. Both the feature of the grain size distribution from fault gouge and the analysis of the fractal dimension have the obvious segmentation along the fault zone. This is consistent with the result from geodetic surveying along the fault zone in recent years.

Key words: Xianshuihe fault, Fault gouge, Microstructure, Fractal, Fault segmentation