海岸山脈東坡河階的地形學研究

Abstract

Owing to the continuous uplift since Quaternary, rejuvenated terraces, gorges and raised alluvial fans are developed well in the eastern slope of Coastal Range. The river terraces in this area are distributed below 200 m generally. The scarps of higher level terrace are larger than that of lower level one. The gravel deposits in higher level terrace are thicker than that of lower level one. Comparing the terrace between six studied rivers, meander terraces are significant both in Mawuku River, Fengpin River, Shuilien Riverand Fanshuliao River whereas fan terraces are developed well in Sanhsien River. In contrary, the terrace in Shuimuting River is undeveloped due to down cutting into hard rock which restricts the widening of terrace. By correlating to marine terraces, most of the terraces in this area are formed in Holocene. The detailed correlation of each step or dating still needs more envidences.