Welcome to visit Geoscience!

Geoscience ›› 2019, Vol. 33 ›› Issue (03): 561-573.DOI: 10.19657/j.geoscience.1000-8527.2019.03.09

• Structural Geology and Stratigraphy • Previous Articles     Next Articles

Genesis and Tectonic Significance of Quartz Sandstones in the Southern Subzone of Tethyan Himalayas: A Case Study on the Paleocene Jidula Formation in Gamba Area, Southern Tibet

LIU Qingshan1,2(), WEI Yushuai1,2(), ZHANG Baosen1,2, PAN Wanying1,2   

  1. 1. School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083,China
    2. Research Center for Tibetan Plateau Geology,China University of Geosciences,Beijing 100083,China
  • Received:2018-07-24 Revised:2019-04-25 Online:2019-06-23 Published:2019-06-24
  • Contact: WEI Yushuai

Abstract:

The Tethyan Himalayas is the main tectonic unit of the northern Indian passive margin. Compared to other similar tectonic units, there are many suites of special quartz sandstones, implying that the terrigenous supply capacity had changed overtime. Tectonic setting and significance of these quartz sandstones are yet to be clear. In this paper, the quartz sandstones (Jidula Formation) in Gamba of the Tethyan Himalayas were analyzed for their detrital compositions, paleocurrent, heavy minerals and detrital zircon ages. Sedimentology and provenance characteristics of these quartz sandstones, their formation and tectonic significance were discussed. According to sedimentary facies analysis, in the Early Paleozoic Gamba area belonged to the Indian passive continental margin of the Neotethys. Littoral facies dominate and show a change from shallow shelf to continental facies. Sandstone lithofacies suggest that the terrigenous clastic material of the Jidula Formation comprises mainly quartz sandstone with very high maturity, and the paleocurrent direction was near NNE. Detrital zircon dating results suggest that the detrital zircon ages of the Jidula Formation coincide with those from the Early Cretaceous Degan Plateau. It is suggested that the formation of quartz sandstones (Jidula Formation) was led by the sudden increase of terrigenous clastic supply in the northern Indian plate margin and the tectonic uplift of the passive continental margin, which was in turn caused mainly by the formation of the Deccan large igneous province (LIP). We concluded that the origin of the quartz sandstones is related to the reactivation of stable cratons caused by the up-doming of the Deccan LIP on the northern Indian plate margin.

Key words: Paleocene, Jidula Formation, quartz sandstone, provenance analysis, Deccan large igneousprovince

CLC Number: