Geochemical and geochronological study of early Carboniferous volcanic rocks from the West Junggar : Petrogenesis and tectonic implications

Hongyan GENG, Min SUN*, Chao YUAN, Guochun ZHAO, Wenjiao XIAO

*Corresponding author for this work

Research output: Journal PublicationsJournal Article (refereed)

130 Citations (Scopus)

Abstract

A series of early Carboniferous volcanic rocks, i.e., basalt, andesite, and dacite, occur in the West Junggar. Zircon U-Pb isotopic data indicate that these rocks coevally erupted at 331-344Ma. These volcanic rocks have comparable trace element patterns, characterized by the enrichment of large ion lithophile elements (LILE) and the depletion of high field strength elements (HFSE). Isotopically, they display consistently depleted Sr-Nd isotopic compositions (initial 87Sr/86Sr ratios=0.7034-0.7054, εNd(t)=4.2-7.7). These rocks are interpreted to be derived from a slightly metasomatized depleted mantle in a normal subduction environment. In the context of a previously proposed ridge subduction model, this study constrains that ridge subduction, if it indeed occurred, commenced between 331 and 310Ma in the central West Junggar.

Original languageEnglish
Pages (from-to)854-866
Number of pages13
JournalJournal of Asian Earth Sciences
Volume42
Issue number5
Early online date8 Feb 2011
DOIs
Publication statusPublished - 10 Oct 2011
Externally publishedYes

    Fingerprint

Keywords

  • Central Asian Orogenic Belt
  • Geochemistry
  • Subduction
  • Volcanic
  • West Junggar

Cite this