Chronology of Pliocene-early Pleistocene lacustrine strata in the Zanda basin, Ngari area, Tibet

Abstract：Neogene Pliocene-Quaternary early Pleistocene strata have been determined through analyses of paleomagnetic and ESR samples from a section of fluvio-lacustrine strata in the Zanda basin, Ngari, Tibet. The analytic results show that： the paleomagnetic ages obtained in ascending order from the section are 5.41-1.60 Ma, while the ESR ages are 5.40-1.36 Ma. The two analytic results roughly coincide. According to the results of the paleomagnetic and ESR datings, the time series of the fluvio-lacustrine strata is as follows： the Pliocene Tolin Formation (N12t) formed at 5.41-4.20 Ma, the Pliocene Guge Formation (N22g) formed at 4.20-2.57 Ma and the Quaternary early Pleistocene Qangzê Formation (Qp1-1x) formed at 2.57-1.36 Ma. This study provides an important basis for the establishment of the time scale of the Neogene Pliocene-Quaternary early Pleistocene strata on the Qinghai-Tibet Plateau and division and correlation of the Neogene Pliocene-Quaternary early Pleistocene fluvio-lacustrine strata.