INTRA-CONTINENTAL DEFORMATION, SPRINGS AND ARID ECOSYSTEMS: NEOTECTONIC FAULTS AS IMPORTANT WATER RESERVOIRS IN ARID AREAS OF XINJIANG PROVINCE, NORTHWEST CHINA

Xinjiang is a province of extremes. Urumqi is the remotest population centre from any sea and historically was part of the Silk Road. It hosts three major deserts – the Gobi, Taklimakan and the Gurbantunggut, which occupy the Tarim, Turfan and Junggar basins. They are separated by intra-continental mountain ranges such as the Tian Shan, Altay Shan and Karakorum. Elevation varies from 7435 m (Tomur Peak) to -154 m (Turpan Pendi). These actively forming mountains and basins are part of a dynamic landscape built by tectonic forces operating over the past 500 Ma to form Eurasia. Recent intra-continental deformation is attributed to the India/Asia collision that was initiated ~50 mya and continues to sculpt Earth's largest continent.

Mountain ranges create microclimates which foster ecological diversity. They contain vital natural resources, including minerals and water. Xinjiang is China's driest province but ice reserves in the Tian Shan have made it one of China's richest in terms of per capita possession of water promoting it as China's main fruit growing region. This study deals with Neotectonic faults and their role as important fresh water reservoirs.

Mountain drainage is channelled along active faults before percolating into internal drainage basins where it is absorbed by alluvial sediments or collects as ephemeral salt lakes. Vegetation is concentrated in small, elongate fault-controlled valleys near permanent water sources. In contrast surrounding areas are sparsely vegetated. Nomadic inhabitants depend upon these water sources to irrigate crops and for the survival of their animal herds.

Active deformation has created climatic and ecological diversity in Central Asia. Faults channel and store water to form permanent oases. Studies of spatial relationships between geology, topography, microclimate and biodiversity can potentially gauge how global climate change will affect less topographically diverse arid environments where isolated ecosystems have less scope to shift into suitable, neighbouring microclimates due to limited topographic range. Active faults and associated springs should rank highly when planning to preserve ecosystems as they allow species to survive outside of the typical environmental range dictated by the surrounding climate. Geodiversity is closely linked to biodiversity.