由形貌特徵指標看臺灣河階的對比

Terrace Correlation in Taiwan from the Morphological Perspective

10.6562/JEE.2012.29.5

孫稜翔(Leng-Hsiang Sun)；沈淑敏(Su-Min Shen)

河階對比 ； 扇階 ； 河階表面 ； 河階底岩面 ； terrace correlation ； fan terrace ； tread ； strath

工程環境會刊

29期（2012 / 07 / 01）

85 - 97

繁體中文

河階對比是藉由河階重建河流地形演育時常用的手段，而階地對比的依據是由相對容易觀察與獲得的各種形態指標開始。本文回顧臺灣從日治時期以來這類倚重形貌指標之對比方法的發展，指出雖然這類方法有時被簡稱為高度對比法，但實際進行階地對比時一向是同時採納多項指標的。即使隨著航遙測和數值地形分析技術的進步，掌握地表形態比以往更為容易，但在對比階地時仍應以河流地形作用和特徵為基礎，推敲各殘餘面的生成區位及所代表的地形意義，思考所擷取之階面高度的代表性，排除人為活動造成的「人工面」，並盡可能納入底岩面與沖積層厚度等資訊，以利於河流地形演育的探討。

The correlation of fluvial terrace is a basic procedure on reconstructing the river evolution history. Morphological properties of terraces are always used as indices since they are relatively easy to obtain, especially those height-related variables. This article reviews the development of the terrace correlation method with morphological indicators in Taiwan, clarifies that the correlation method has always been multi-indices. It is also emphasized that, no matter the rapid progress on the digital photogrammetry and digital topographical analysis, for terrace correlation it is essential to interpret residual geomorphic surfaces based on fluvial geomorphology, detect the representative height value of terraces, exclude artificial geomorphic surfaces, and incorporate straths height and the thickness of terrace sediments.