There are a series of basins in the Fenwei Graben. Field survey found that there took place several paleolake regressions or intensive stream down-incisions in all basins during the Mid-Late Quaternary. The lowest and...There are a series of basins in the Fenwei Graben. Field survey found that there took place several paleolake regressions or intensive stream down-incisions in all basins during the Mid-Late Quaternary. The lowest and oldest paleosol/Ioess units overlying three of the lacustrine terraces or alluvial ones and some paleomagenetism data from the lacustrine sediment indicate that the onset times of three paleolake regressions or intensive stream down-incisions are synchronous with the formation of Lg, L6 and L2 respectively in the Weihe Basin, $8, S~ and $1 respectively in the Linfen-Taiyuan-Xingding Basins, and Ls, Ls and L1 respectively in the Datong Basin. The difference in the onset time of each lake regressions or intensive stream down-incision in different basins reveals that the farther the basin is from the Tibetan Plateau, the later it took place. Taking these field facts and the former research re- sults in terms of the regional tectonic movement into account, it is inferred that the tectonic movement of the Tibetan Plateau most probably controlled such geomorphological- sedimentary evolution in the graben.展开更多
基金Foundation: National Natural Science Foundation of China, No.41371021
文摘There are a series of basins in the Fenwei Graben. Field survey found that there took place several paleolake regressions or intensive stream down-incisions in all basins during the Mid-Late Quaternary. The lowest and oldest paleosol/Ioess units overlying three of the lacustrine terraces or alluvial ones and some paleomagenetism data from the lacustrine sediment indicate that the onset times of three paleolake regressions or intensive stream down-incisions are synchronous with the formation of Lg, L6 and L2 respectively in the Weihe Basin, $8, S~ and $1 respectively in the Linfen-Taiyuan-Xingding Basins, and Ls, Ls and L1 respectively in the Datong Basin. The difference in the onset time of each lake regressions or intensive stream down-incision in different basins reveals that the farther the basin is from the Tibetan Plateau, the later it took place. Taking these field facts and the former research re- sults in terms of the regional tectonic movement into account, it is inferred that the tectonic movement of the Tibetan Plateau most probably controlled such geomorphological- sedimentary evolution in the graben.