Late Cenozoic tectonic movement in the Keyir Mountain area, Kuqa, Xinjiang, and its controls on sandstone-type uranium deposits

Abstract：The Keyir Mountain area, located at the northern edge of the Kuqa-Baicheng depression of the Tarim Basin, is one of the favorable areas for the formation of sandstone-type uranium deposits in NW China. Field geological survey and interpretation of remote-sensing images have revealed that not only E-W-trending thrust faults and folds but also E-W-trending normal faults and a half-graben are developed in the study area. Stratigraphic correlation and development of unconformities indicate that these thrust faults and folds formed during the terminal Neogene to Early Quaternary, and E-W-trending normal faults and the half-graben formed later than the Middle Pleistocene. Therefore, the Late Cenozoic tectonic evolution process of the Keyir Mountain area is reconstructed. It is inferred that a regional N-S compressional environment occurred in the Neogene to early Pleistocene, while a local extensional environment from the late Pleistocene to present time. According to the above-mentioned study, combined with an analysis of the mineralization conditions for sandstone-type uranium deposits, the authors suggest that the uplifting segments of the a monoclinal zone in the northern part of the Keyir Mountain area are favorable areas for the formation of sandstone-type uranium deposits and should be firstly explored.