Quaternary glacier development and the relationship between the climate change and tectonic uplift in the Helan Mountain

孤立拉长 Helan 山脉山岳的 NE-SW，分开从 Tenggeli 沙漠的 Ordos 高原的适度的草地，是在西方中国学习冰河发展的一个关键位置以及气候的联合条件随着变化构造高举。冰川的地形和存款包括冰斗，山峰，刀口山脉，侧面的冰碛，和终端冰碛在 Helan 山的中间的部分在 2800 m a.s.l 上面散布。这分布显示这曾经是 glaciated 在期间晚第四级。形态学特征证明形成事件的风景的一个清楚的序列发生在整个 Helan 山。实验室光学地刺激了光(OSL ) 和标明日期的加速器团 spectrometry 放射性碳(AMS 14C ) 结果显示冰川的进展的迟了的历史。在 Helan 山的中间的部分的迟了的更新世冰河进展了接近他们的位置至少四次，并且冰川的序列能作为最后一个冰川的周期的中间的阶段被分配(MIS3b， 43.2 ????????? ′ ? 錸? 錸?@

Isolated NE-SW stretching the Helan Mountain massif, separating the temperate grassland of the Ordos plateau from the Tenggeli Desert, is a key position of studying the glacier development in west China as well as the coupling conditions of climate change with tectonic uplift. The glacial landforms and deposits including cirques, peaks, knife-edge ridges, lateral moraines, and terminal moraines distribute above 2800 m a.s.1, in the middle part of the Helan Mountain. This distribution indicates that here was once glaciated during the late Quaternary. Morphology features show a clear sequence of landscape forming events took place throughout the Helan Mountain. Laboratory optically stimulated luminescence （OSL） and accelerator mass spectrometry radio- carbon dating （AMS 14C） results indicate a late history of glacial advance. Late Pleistocene glaciers in the middle part of the Helan Mountain advanced to near their positions at least four times, and the glacial sequences can be assigned as the middle stage of last glacial cycle （MIS3b, 43.2±4.0 ka）, last glacial maximum （LGM, -18 ka）, late glacial （12.0±1.1 ka） and neo-glacial （3.4± 0.3 ka） respectively. Adopting equilibrium line altitude -2980 m of last glacial maximum and the modern theoretical snowline altitude -4724 m as the maximum amplitudes, and the standard marine isotope curve （MIS） as the glacial equilibrium line change since the Gonghe Movement （150 ka）, the relationship between the mountain altitude and glacier development is discussed herein. Compared with other environmental indexes such as the loess-paleosol and ice core, conclusions are made that glacier advances in the Helan Mountain during the late Quaternary obviously depended on the coupled control of tectonic uplift of mountain with the climate condition. It is at last glaciation that the mountain reached the altitude above snowline and coupled with the glacial climate. The glacial advances occurred in the early and middle stages of last glacial cycle after the Gonghe Movement.