大肚溪為台灣中西部地區三大主要的河川之一，並且與多條重要的斷層相交，其河階台地發育廣闊，且分佈之特性與斷層活動息息相關，因此本文針對大肚溪之河流及河階地形進行研究，以瞭解新構造運動對大肚溪地形之影響。本文使用研究區域內各不同比例尺之地形圖、各不同時期航空照片、40公尺網格及20公尺網格之數值地形等資料，利用地理資訊系統作資料的輸入、管理、分析及展示，並針對大肚溪沿岸的河階地形進行研究。野外工作主要針對河階地的特性，以土壤鑽取器採樣以進行紅土化分析，並觀察河階之堆積層特性及基底岩層出露與否等項目。室內工作則針對大肚溪流域進行各項地形分析，如河流縱斷面分析、河流坡降指數分析等，藉此研究結果以解釋大肚溪流域之新構造運動。研究結果顯示，大肚溪的河流及河階地形皆反應了彰化斷層與車籠埔斷層的活動性較高，且斷層活動造成五階的高位河階，車籠埔斷層於近期之活動則造成三階低位河階及發達的山前沖積扇。 The Tatu Creek is one of the three major rivers in the central Taiwan. It crosses several important faults. River terraces and tablelands are well developed in the drainage-basin of Tatu Creek, and the distribution seem to be related to the activity of those faults. To Clarify the influences of neotectonics to the Tatu Creek, the river and terrace geomorphology of the Tatu Creek are analyzed in this study. Topographic maps in different scales, aerial photographs taken from different period, and Digital Terrain Model (DTM) in 20m and 40m resolution which covering the study area were used to study the geomorphic features of Tatu Creek. Geographic Information System (GIS) is used to data input, management, analysis and display. In the field investigation, we use the hand auger to obtain the soil samples, their colors were analyzed to compare the lateritization of different terrace. We also observe several characters of terraces, for example, the thickness of gravel deposits and bedrock exposure. For laboratory work, we analyzed the river longitudinal profile and the stream length-gradient index of main course of the Tatu Creek. According to the results of geomorphic analysis, the neotectonics in the drainage-basin of the Tatu Creek were discussed and illustrated. The result shows that the river and terrace geomorphology of Tatu Creek do reflect the high activity of the Changhua fault and the Chelungpu fault. The thrust faulting caused uplift of hanging wall and produced five levels of lateritic terrace. The recent activity of Chelungpu fault is clearly related to the formation of three levels of fluvial terrace and a broad mountain front alluvial fan.