Welcome to visit Geoscience!

Geoscience ›› 2021, Vol. 35 ›› Issue (02): 477-491.DOI: 10.19657/j.geoscience.1000-8527.2020.056

• Petrology • Previous Articles     Next Articles

LA-ICP-MS Zircon U-Pb Dating, Geochemical Characteristics and Tectonic Significance of Neoproterozoic Granite in the Quruqtagh Area,Northern Margin of Tarim Craton,NW China

CHEN Bangxue1(), XU Shengli1, ZHOU Nengwu2(), BAI Quanjin2, LI Chao1, ZHANG Hongshen1   

  1. 1. Shaanxi Geological Exploration Institute of Geology and Mine Bureau, Xi’an,Shaanxi 710000,China
    2. No.11 Geological Party,Xinjiang Bureau of Geology and Mineral Exploration and Development,Changji,Xinjiang 831100,China
  • Received:2019-06-21 Revised:2020-05-25 Online:2021-04-25 Published:2021-05-25
  • Contact: ZHOU Nengwu

Abstract:

In this study, we conducted LA-ICP-MS zircon U-Pb dating on the monzogranite from the Quruqtagh area, which yielded a concordant age of (832.3±3.3) Ma (MSWD=2.8,n=24).The monzogranite is metaluminous,high-K calc-alkaline,and I-type. As for trace elements, the samples are enriched in large-ion lithophile elements (LILEs, e.g., Ba, K, Sr and U) and depleted in high field strength elements (HFSEs, e.g., Nb, Ta, Ti and P). The total rare earth element (REE)contents are relatively low (29.88×10-6 to 63.57×10-6), and the samples exhibit weakly positive Eu anomaly (δEu=0.87 - 1.39). The overall trace element distribution pattern resembles that of the lower crust. Comprehensive analysis of magmatic lithogeochemistry and regional geological background shows that the monzonitic granite was likely formed in an island arc environment.Combined with the regional tectonic evolution, we considered that the oceanic crust in the region began to subduct at around 832 Ma. This may have made the crust thicker, and the heating from the upwelling mantle plume may have partially melted the ancient crust materials, forming the Neoproterozoic granites.

Key words: Neoproterozoic, granite, Rodinia super continent, Tarim Craton, Quruqtagh

CLC Number: