Geomorphological analysis of earthquke surface fault associated with reverse active fauting

本研究的目的是分析地震地表断层与构造地貌的关系。研究了1999年台湾赤赤地震、1948年虎魁地震、1927年北探戈地震、1847年真古寺地震、1945年三川地震和1998年岩手根奈陆-北部地震中沿龙坡断裂带的地震地表断层。这些地震与地震地表断层有关。在大尺度航空照片解译和野外调查的基础上，认识了地震断裂带沿线的构造地貌。弯曲陡坡是这些地震地表断层的典型变形特征，表明这是由低角度逆断层作用造成的。研究区地震地表断层大部分位于已存在的活动断层地貌中，但也有部分断层远离已存在的活动断层地貌。弯曲陡坡位于距山前线100米至1公里处，表明近期逆断裂向盆地迁移。研究区褶皱体系发育良好，表明褶皱与松散盆地沉积晚第四纪断裂作用有关。

The purpose of this study is to analyze the relationship of earthquake surface fault and tectonic landform. The earthquake suface faults along the Chelungpeu Fault during the Chi-Chi earthquake 1999 in Taiwan, Hukui earthquake 1948, Kita-Tango earthquake 1927, Zenkoji earthquake 1847, Mikawa earthquake 1945 and Iwate-ken Nairiku-Hokubu earthquake 1998 are investigated. These earthquakes associated with earthquake surface faults. Tectonic landform are recognized along these earthquake fault, based on the interpretation of large-scale air photographs and the field survey.Flexural scarps are a characteristic deformed feature along these earthquake surface faults, implying that this is resulted from low angle reverse faulting.Most of earthquake surface faults in study areas situated in pre-existing active fault landforms, however a part of them is located away from pre-existing active fault landforms. Flexural scarps are situated one hundred meters to one kilometer off from the piedmont line, which indicates that recent reverse faulting migrates to the basin. The fold systems well develop in the study areas, which shows that the folding is related to the late Quaternary faulting in the unconsolidated basin deposits.