A new cache of Eoarchaean detrital zircons from the Singhbhum craton,eastern India and constraints on early Earth geodynamics

作     者：Bulusu Sreenivas Sukanta Dey Y.J. Bhaskar Rao T. Vijaya Kumar E.V.S.S.K. Babu Ian S. Williams 

作者机构：CSIR-National Geophysical Research InstituteHyderabad 500007India Department of Earth SciencesIndian Institute of Science Education and ResearchKolkata 741246India Research School of Earth SciencesThe Australian National UniversityCanberra 2601Australia 

出 版 物：《Geoscience Frontiers》 (地学前缘（英文版）)

年 卷 期：2019年第10卷第4期

页      面：1359-1370页

核心收录：

学科分类：07[理学] 

基　　金：Financial support from the Ministry of Earth Sci-ences,New Delhi for Excimer 193 nm LA system at CSIR-NGRI MoES/P.O.(Seismo)/1(245)/2014 for the project on Singhbhum craton to S.D.,E.V.S.S.K.B.,B.S.and T.V.K(No.MoES/P.O.(Geosci)45/2015 GAP-738-28EVB) part of the CSIR-NGRI projects INDEX(PSC0204) and GEOMET 

主　　题：U-Pb zircon ages Hf isotopes Singhbhum craton Hadean Eoarchean Geodynamics 

摘      要：The dominant geodynamic processes that underpin the formation and evolution of Earth’s early crust remain enigmatic calling for new information from less studied ancient cratonic ***,we present U-Pb ages and Hf isotopic compositions of detrital zircon grains from^2.9 Ga old quartzites and magmatic zircon from a 3.505 Ga old dacite from the Iron Ore Group of the Singhbhum craton,eastern *** detrital zircon grains range in age between 3.95 Ga and 2.91 *** with the recently reported Hadean,Eoarchean xenocrystic(up to 4.24 Ga)and modem detritus zircon grains from the Singhbhum craton,our results suggest that the Eoarchean detrital zircons represent crust generated by recycling of Hadean felsic crust formed at^4.3-4.2 Ga and^3.95 *** observe a prominent shift in Hf isotope compositions at^3.6-3.5 Ga towards super-chondritic values,which signify an increased role for depleted mantle and the relevance of plate *** Paleo-,Mesoarchean zircon Hf isotopic record in the craton indicates crust generation involving the role of both depleted and enriched mantle *** infer a short-lived suprasubduction setting around^3.6-3.5 Ga followed by mantle plume activity during the Paleo-,Mesoarchean crust formation in the Singhbhum *** Singhbhum craton provides an additional repository for Earth’s oldest materials.