Gravel bodies in the Kumtagh Desert and their geomorphological implications
Gravel bodies in the Kumtagh Desert and their geomorphological implications
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DOI：
10.1007/s12665-009-0159-5
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发表时间：
2010-02
影响因子：
2.8
通讯作者：
Z. Dong;Guangqiang Qian;P. Yan;Z. Su
中科院分区：
文献类型：
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作者：
Z. Dong;Guangqiang Qian;P. Yan;Z. Su
尽管沙漠地貌是在主要干旱的环境中发展起来的，但它有时也包含有关过去环境变化的信息。研究人员最近才对中国的库姆塔格沙漠进行了研究。这些调查揭示了与中国其他沙漠相比存在的一些独特特征，包括分布在沙漠北部的砾石体。本文总结了该地区前期研究成果以及遥感和野外调查资料，讨论了该地区的地质背景、第四纪地貌，以及沙漠砾石体的类型、发育阶段和地貌意义。确定了四种主要砾石体类型和四个发育阶段。认为青藏高原隆升造成的阿尔金山与库姆塔格沙漠之间的巨大高差构成了砾石体发育的总体背景，但随后的气候事件是其演化的直接原因。砾石体是由主要由风成而来的松散细沉积物上的冲积沉积物形成的，随后遭受风蚀。然后，侵蚀循环逐渐分散这些砾石，形成砾石片。砾石体具有三个主要地貌意义：记录了沙丘场形成后的古代气候异常事件，对东北部附近赛义夫沙丘的发育影响不大；证明阿尔金山是库姆塔格沙漠的主要沉积源；提示库姆塔格沙漠环境和地貌的演化受到新构造运动的影响。
Although developed in predominantly arid environments, desert geomorphology sometimes bears information about past environmental change. China’s Kumtagh Desert has only recently been studied by researchers. These investigations revealed the existence of several unique features compared with other Chinese deserts, including gravel bodies distributed in the northern part of the desert. This paper summarizes the results of previous research in the region, as well as information obtained from remote sensing and field investigations, then discusses the geological background, underlying Quaternary geomorphology, and the types, development stages, and geomorphological implications of the desert’s gravel bodies. Four main types of gravel bodies and four developmental stages were identified. It is suggested that the great elevation difference between the Altyn Tagh Mountains and the Kumtagh Desert caused by uplift of the Qinghai-Tibetan Plateau constitutes the overall background for the development of gravel bodies, but subsequent climatic events were the direct causes of their evolution. The gravel bodies resulted from alluvial deposits on loose fine sediments mainly of aeolian origin that were subsequently subjected to wind erosion. Erosion cycles then progressively scattered these gravels to form gravel sheets. The gravel bodies have three main geomorphological implications: they record anomalous ancient climate events after the dune field formed and have little influence on the development of nearby seif dunes in the northeast, demonstrate that the Altyn Tagh Mountains are the main sediment source for the Kumtagh Desert, and suggest that the evolution of the environment and geomorphology of the Kumtagh Desert have been influenced by neotectonic movements.