Abstract:
Based on analyzing composite characteristics of heavy minerals from clastic rocks of Jiusi-Wujiaping Stage in Ejina Banner and its adjacent areas, in combination with regional geological features, lithologic character of clastic rocks, detrital zircon dating data, ancient flow direction and the depositional system, this paper deals with the provenance system of the Carboniferous-Permian sediments. Heavy mineral combinational features reveal that combination types and content of heavy minerals are different in northern Heiying Mountain, Ejin Banner depression and southern Liuyuan-Manghanchaoke depression, suggesting that they were probably derived from different sedimentary sources. According to detrital zircon dating data, there are two types of detrital zircon age of Maihanhada Formation in Lvyuan-Guaizihu depression, being 436Ma±13Ma and 1467Ma±110Ma in age respectively. Ancient flow direction also reveals the existence of northern sedimentary source. These data suggest that the sedimentary source experienced dual action from both Dunhuang-Alashan-Langshan ancient land and Mazongshan-Guaizihu uplift belt. The sedimentary source of northern depression was Mazongshan-Guaizihu uplift.