tailieunhanh - U-Pb detrital zircon geochronology of sedimentary rocks in NE Vietnam: Implication for Early and Middle Devoni-an Palaeogeography

We present detrital zircon U-Pb analytical results from two samples, the Van Canh and the Van Huong Formations (east Red River Basin). Zircons were analyzed for U, Th, and Pb isotopes by LA-SF ICP-MS techniques. The youngest zircon of each formation provides maximum ages of sedimentation at ± Ma and ± Ma. The zircon cluster of both samples supports the postulated position of NE Vietnam close to the western Himalaya. | Vietnam Journal of Earth Sciences, 39(4), 303-323, DOI: Vietnam Academy of Science and Technology Vietnam Journal of Earth Sciences (VAST) U-Pb detrital zircon geochronology of sedimentary rocks in NE Vietnam: Implication for Early and Middle Devonian Palaeogeography Königshof P.*1, Linnemann , Ta Hoa Phuong3 1 Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, 60325 Frankfurt, Germany 2 Senckenberg Naturhistorische Sammlungen Dresden, Museum für Mineralogie und Geologie, GeoPlasma Lab, Königsbrücker Landstraße 159, 01109 Dresden, Germany 3 Hanoi National University, 334 Nguyen Trai Str., Thanh Xuan Dist., Hanoi, Vietnam Received 18 April 2017. Accepted 27 July 2017 ABSTRACT Rocks of the Do Son Peninsula in NE Vietnam are mainly composed of Palaeozoic siliciclastics. The overall sedimentary record represents fluvial to deltaic prograding deposits close to a shoreline. We present detrital zircon U-Pb analytical results from two samples, the Van Canh and the Van Huong Formations (east Red River Basin). Zircons were analyzed for U, Th, and Pb isotopes by LA-SF ICP-MS techniques. The youngest zircon of each formation provides maximum ages of sedimentation at ± Ma and ± Ma. The zircon cluster of both samples supports the postulated position of NE Vietnam close to the western Himalaya. Keywords: U-Pb detrital zircon; Palaeogeography; Terrane; Van Huong; Van Canh Formations; Vietnam. ©2017 Vietnam Academy of Science and Technology 1. Introduction1 Southeast Asia is composed of a complex puzzle of various terranes (Figure 1) which were rifted from Gondwana during the Early Palaeozoic through the Jurassic times (. Metcalfe, 1984; Burrett and Strait, 1985, 1987; Burrett et al., 1990; Metcalfe, 2011; Usuki et al., 2013). From the Palaeozoic to the Cretaceous several major terranes, including the South China, North China, Indochina, .