Key Techniques and Several Cases in Paleoseismic Studies in Mainland China (1)： Trenching Sites, Layouts and Paleoseismic Indicators on Active Strike-Slip Faults

详细信息   

• 责任者：Ran Yongkang (Key Laboratory of Active Tectonics and Volcano ; China Earthquake Administration ; Beijing 100029 ; China) ; Wang Hu
• 刊名：Seismology and Geology
• 出版年：2012
• 卷期：34(2)
• 关键词：古地震 ; paleoearthquakes ; 走滑断层 ; strike-slip faults ; 中国 ; China
• 页码：p.197-210
• 图表：6 illus., 27 refs.
• 分类号：0500
• issnNo：ISSN0253-4967
• isbnNo：CN11-2192/P

摘要

///Through comprehensive analysis on characteristics of coseismic surface ruptures and influencing factors on several trenching cases, the authors suggest micro-landforms such as depressions, basins, troughs, sag ponds, successive-offset channels, continuous scarp-derived deposit and multiple geomorphic surfaces are likely to be good trenching sites for paleoseismic studies on strike-slip faults. Multiple trenching or three-dimensional trenching should be the primary layout on strike-slip faults. Offsets of micro-landform across a fault, young stratigraphic units overlying on faulted units, locally distributed scarp-derived colluvial deposits, filled fissures,abrupt increases or decreases in displacement of different stratigraphic units on a fault, warping in different degrees, and multiple periodic paleo-sag ponds accumulation, all of these deformation evidences are good indicators for identifying paleoseismic events.