Switching from advancing to retreating subduction in the Neoproterozoic Tarim Craton, NW China: Implications for Rodinia breakup

Geoscience Frontiers

Wei Liu¹  Yang Xiao²  Shuai Yang³  Xin Chen⁴  Zecheng Wang⁵  R. Damian Nance⁶  Guanghui Wu⁶ 

[1] Corresponding author. School of Geoscience and Technology, Southwest Petroleum University, Chengdu 610500, China.;Development, Beijing 100083, China;Southwest Petroleum University, Division of Key Laboratory of Carbonate Reservoirs, CNPC, Chengdu 610500, China;Department of Geological Sciences, 316 Clippinger Laboratories, Ohio University, Athens, OH 45701, USA;;PetroChina Research Institute of Petroleum Exploration &School of Geoscience and Technology, Southwest Petroleum University, Chengdu 610500, China;

关键词: Supercontinent breakup;    Top-down tectonics;    Rodinia;    Subduction;    U–Pb–Hf isotopes;   

DOI  :  

来源: DOAJ

【 摘 要 】

Geodynamic drivers for the supercontinent cycle are generally attributed to either top-down (subduction-related) or bottom-up (mantle-related) processes. Compiled geochemical data and U–Pb ages and Hf isotopic signatures for magmatic and detrital zircons from the Tarim Craton reveal a distinct change in subduction style during the Neoproterozoic. The subduction cycle is recorded in increasing and decreasing intensity of subduction-related magmatic rocks and time-equivalent sedimentary successions, and converse trends of εHf(t) values and corresponding changes in crustal incubation time. These trends are consistent with a switch from advancing to retreating subduction. The switch likely occurred at ca. 760 Ma when zircon εHf(t) values increase and crustal incubation times decrease following a transitional shift between 800 ​Ma and 760 ​Ma. A switch at this time is consistent with Rodinia breakup and may have resulted in the late Neoproterozoic Tarim rift basin. The long-lived (ca. 500 Ma) subduction recorded in the Tarim Craton suggests the predominance of a top-down process for Rodinia breakup on this part of its margin.

【 授权许可】

Unknown