The Carboniferous paleokarst in Akqi area of Xinjiang and its geological significance

Carboniferous strata are perfectly developed in Akqi area on the northwest margin of Tarim basin and can be divided into Bashisuogong Formation, Biegengtawu Formation and Kangkelin Formation in upward succession. Abundant paleokarst breccias and paleokarst structures were discovered in Bashisuogong Formation and Biegengtawu Formation, in which five distinct large-scale paleokarst cycles are well developed vertically. This paper gives a detailed description of the above-mentioned paleokarst structures and paleokarst cycles, discusses the relationship of the paleokarst to regional sea-level changes and the contemporaneous glacial events, and points out the close relationship of the early Late Carboniferous paleokarst with regional bauxite ore-forming events, which could shed light on the exploration of bauxite deposits in the study area.