Petrogenesis of the Early Cretaceous Xi’anli Hornblende-Gabbros from the Southern Taihang Mountains: Evidence from Zircon U-Pb Geochronology, Hf Isotope and Whole-Rock Geochemistry

详细信息   

• 责任者：Wang Chunguang (College of Earth Science ; Jilin University ; Changchun 130061 ; China) ; Xu Wenliang
• 刊名：Earth Science
• 出版年：2011
• 卷期：36(3)
• 关键词：角闪辉长岩 ; hornblende gabbro ; 铀—铅计时 ; U-Pb dating ; 太行山 ; Taihang Mountains
• 页码：p.471-482
• 图表：8 illus., 3 tables, 60 refs.
• 分类号：0801
• issnNo：ISSN1000-2383
• isbnNo：CN42-1233/P

摘要

This paper reports zircon U-Pb geochronology, Hf isotope, and whole-rock geochemical data, aimed at constraining the petrogenesis of the hornblende (Hb)-gabbros from the Xi’anli intrusion in the southern Taihang Mountains (Mts.).The intrusion is composed mainly of olivine-bearing Hb-gabbro, Hb-diorite, and diorite. Zircons from the Hb-gabbros display euhedral shape and zonal homogeneous absorption on CL images, and have high Th/U ratio (1.44-2.85), suggesting a magmatic origin. Combined with the mineralogical and geochemical study of the dunite xenolith and the olivine xenocrysts hosted in the Hb-gabbros, we propose that the Xi’anli Hb-gabbros may have been produced by the reaction of the delaminated lower continental crust-derived melt and mantle peridotite.