敦煌雅丹地貌区晚更新世以来的区域构造运动特征

河流阶地和活动断层是研究区域构造运动的良好证据。分析了敦煌雅丹地貌区的活动断层和河流阶地的特征与性质，并取样测定活动断层形成时间，进而通过区域对比确定研究区晚更新世以来的构造运动特征和性质。研究区晚更新世以来受区域构造运动影响强烈，特别是阿尔金构造系和北山构造系的次级构造对研究区影响明显。距今约10万年以来，研究区共发生过3次明显的间歇性构造抬升活动：Ⅰ期发生于距今约10万年前，强度最弱；Ⅱ期发生于距今约7万年前，最为强烈；Ⅲ期发生在距今4万年前。

Characteristics of Regional Tectonic Movement of Dunhuang Yardang Area in Late Pleistocene

River terraces and active faults are excellent evidence for regional tectonic movement. In this paper, river terraces and active faults in Dunhuang Yardang area were studied. By fault gouge dating and comparison with regional neotectonic movements, characteristics and mechanism of tectonic movement in Late Pleistocene were detailed. The study area was affected evidently by regional neotectonic movement since Late Pleistocene, especially by the Arkin Faults and Beishan Faults. Combining field investigation and dating, the paper arrived at conclusions as follows:there has been three stages of intermittent tectonic uplift since 100 kyr BP, the first stage happened at about 100 kyr BP, with the lowest fierceness; the second stage happened at about 70 kyr BP, which was the fiercest; and the third stage happened at about 40 kyr BP.