摘要
The 7200-m-deep Well Tacan 1 in the central Tarim Basin is the deepest in China. Purplish gray medium-grained granodiorite containing dark gray fine-grained diorite xenolith is revealed at the base of the well (7169―7200 m), and they are results of the Jinning magmatic activities. Trace-element geochemistry and REE profiles of both rock types are similar, indicating that they are calc-alkaline series I-type granitoid. Proxies of diorite signify the development of a magmatic arc due to subduction at ca. 1200 Ma. The granodiorite was formed before 890―932 Ma. However, more study is needed to clarify if the arc diorite represents a ca. 300 Ma extension of the subduction or a reactivation during the orogenic collision event at ca. 900 Ma.
The 7200-m-deep Well Tacan 1 in the central Tarim Basin is the deepest in China. Purplish gray medium-grained granodiorite containing dark gray fine-grained diorite xenolith is revealed at the base of the well (7169―7200 m), and they are results of the Jinning magmatic activities. Trace-element geochemistry and REE profiles of both rock types are similar, indicating that they are calc-alkaline series I-type granitoid. Proxies of diorite signify the development of a magmatic arc due to subduction at ca. 1200 Ma. The granodiorite was formed before 890―932 Ma. However, more study is needed to clarify if the arc diorite represents a ca. 300 Ma extension of the subduction or a reactivation during the orogenic collision event at ca. 900 Ma.
作者
LI Yuejun1, 2, SONG Wenjie2, WU Genyao1, WANG Yifen1, LI Yuping2 & ZHENG Duoming2 1. Institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing 100029, China
2. Tarim Oil-field Company, PetroChina, Korla 841000, China
基金
This work was supported by the National Natural Science Foundation of China(Grant No.40072077).
