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。考察了1999年台湾集集地震、1948年虎奎地震、1927年基塔探戈地震、1847年增古地震、1945年宫川地震和1998年岩手县奈陆部-北部县地震期间车龙坪断裂沿线的地震断层。这些地震与地震地表断层有关。根据大比例尺航片的解释和野外调查，这些地震断层沿线的构造地貌被识别出来。弯曲陡坎是这些地震断层沿线的一种特征变形特征，这意味着这是低角度逆断裂作用的结果。研究区的地震地表断层大多位于原有的活动断裂地貌中，但也有一部分位于远离原有的活动断裂地貌的地方。弯曲的陡坎位于距离山前100米到1公里的地方，这表明最近的反向断裂活动迁移到了盆地。研究区内褶皱系统发育，表明褶皱与松散盆地沉积中的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.