Cenozoic uplift of the Qimantage Mountains, northeastern Tibet: Contraints from provenance analysis of Cenozoic sediments in Qaidam Basin

Abstract

Qimantage Orogen as the western part of East Kunlun Mountains is located in the northeastern margin of the Tibet Plateau. In this contribution, detrital zircon age spectra combined with heavy mineral analysis of Cenozoic sediments from Qaidam Basin were applied to reveal the uplift history of Qimantage Mountains. Our results show that the Cenozoic staged uplift of the Qimantage Mountains exhibit eastward and northward uplift characteristics. From the middle Eocene to Quaternary, there are three major uplift stages for Qimantage Mountains: the first stage is from middle Eocene to late Eocene (~45–35.3 Ma). The range developed a topographic pattern of east‐high and west‐low at that time, and the uplift of the east part range at that time is significant perhaps linked to the Cenozoic uplift of Tibetan Plateau due to its significant crustal shortening. The second stage is from early Oligocene to late Miocene (~15–8 Ma). During this stage, the uplift is both significant in tectonic and topographic aspects, and the overall uplift occurred mainly in the middle and west part of Qimantage Mountains. The last stage is from late Miocene to Quaternary (~2.8 Ma to present), and the Qimantage Mountains experienced complete uplift. The provenance is mainly the northern Qimantage Mountains without sediments supplied from further south, and therefore, the Qaidam Basin became an intermontane basin geomorphically.