The Yardang Landform of Aqik Valley in the East of Lop-Nor and its Relationship with the Evolution of the Kumtagh Desert
The Yardang Landform of Aqik Valley in the East of Lop-Nor and its Relationship with the Evolution of the Kumtagh Desert
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发表时间：
2004
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通讯作者：
Yu Qi-hao
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作者：
Yu Qi-hao
Aqik山谷位于Lop-Nor凹陷和东经93°之间。长约150公里，宽约20~30公里。它是阿尔金山与白山山之间新近系地堑坳陷的一部分。它的伦敦东区与河西走廊洼地相连。根据雅尔丁地层的ESR测年和区域地貌特征，将阿其克河谷和库姆塔格沙漠的演化历史划分为4个阶段：（1）罗布泊大湖阶段;该阶段为早更新世至中更新世。湖的东侧约在东经93°15′或更远，湖的东部宽50~60 km。(2)山隆湖退阶段。中更新世晚期（约300 kaBP），青藏高原的强烈隆升对海洋性气团形成屏障，导致中亚地区气候变干。在阿尔金山脉北部，古湖泊地层中发育深成的深泓断谷群。原因是阿尔金山正在向东移动。区内存在两组断裂（一组为EW向，另一组为NE向）。因此，疏勒河的水不会流入罗布泊。其东湖流域逐渐干涸。(3)暴雨侵蚀和强风蚀阶段。中更新世晚期至晚更新世早期，在阿其克河谷北部分支河口处发育了多个雅丹群。在山谷的南侧，有许多NE方向的，近雅丹山脉和风蚀山谷。在Aqik山谷的中部，有季节性的盐沼和孤立的Yardang。(4)晚更新世末和全新世库姆塔格沙漠扩张阶段。在这一阶段，沙丘向北扩展，并掩盖了羽状断层谷。因此，风蚀山谷和雅丹山脉成为世界上最令人难以置信的羽状沙丘。
The Aqik Valley is located between the Lop-Nor depression and longitude 93°E. It is about 150 km long and 20～30 km wide. It is a part of the Neogene graben depression between the Aljin Mountains and the Baishan Hill. Its east end is adjoined to the Hexi Corridor depression. Based on the ESR dating of the Yarding strata and regional geomorphological features, the evolution history of the Aqik Valley and the Kumtagh Desert can be divide into four stages: (1) The big lake stage of Lop-Nor. This stage is from early Pleistocene to middle Pleistocene. The east side of the lake is at about longitude 93°15′E or more far, and the east part of the lake had 50～60 km wide. (2) The mountain uplift and lake retreat stage. During late middle Pleistocene (about 300 ka BP), the strong uplift of the Qinghai-Tibetan Plateau formed a barrier for the maritime air mass, and this caused the climate of Central Asia to be drier. In the north of the Aljin Mountains, plumetic fault valley group occurred in the strata of old lakes. The reason is that Aljin Mountains is moving eastward. In this region, there are two groups of faults (one EW direction, the other NE direction). So, the water of Shule River doesnt flow into the Lop-Nor. Its east lake valley is dried up gradually. (3) The rainstorm erosion and strong wind erosion stage. During the late Middle Pleistocene and the early Late Pleistocene, there are many Yardang groups at the branch river mouth of the north part of Aqik Valley. In the southern side of the valley, there are many NE direction, paralleled Yardang ranges and wind-eroded valleys. In the middle of the Aqik valley, there are seasonal salt marsh and isolated Yardang. (4) The expanding stage of Kumtagh Desert at the end of Late Pleistocene and Holocene. In this stage, the dunes expanded northward and covered up the plumetic fault valleys. Hence, wind erosion valleys and Yardang ranges became the most incredible plumetic sand dunes in the world.