Late Cenozoic high-resolution magnetostratigraphy in the Kunlun Pass Basin and its implications for the uplift of the northern Tibetan Plateau

摘要

The Kutntan Pass Basin, located in the of the eastern Kentan Mountains, received relatively continuous late Cenozoic sediments from the surrounding mountains, archiving great information to understand the deformation and uplift histories of the northern Tibetan Plateau. The Kunlun-Yellow River Movement, identified from the tectonomorphologic and sedimentary evolution of the Pass Basin by Cui Zhijiu et al. (1997, 1998), is roughly coincident with many important global and Plateau climatic and environmental events, becoming a crucial time interval to understand tectonic-climatic interactions. However, the used to constrict the events remain great uncertainty. Here, we present the results of detailed magneto-stratigraphy of the late Cenozoic sediments in the Kuntan Pass Basin, which show the basin sediments were formed between about 3.6 Ma and 0.5 Ma and the Kuatan-Yellow River Movement occurred at 1.2 to -0.78 Ma. The lithology, sedimentary facies and lithofacies associations divide the basin into five stages of tectonosedimentary evolution, indicating the northern Tibetan Plateau having experienced five episodes of tectonic uplifts at -3.6, 2.69-2.58, 1.77,1.2, 0.87 and -0.78 Ma since the Pliocene.