Geocgronology of Ji' an Group in Tonggua Area,Soutgern Jilin Province
Qin Ya
Chen Dandan
Liang Yihong
Zou Cunming
Zhang Qingwei
Bai Ling an
Abstract：The chronology of volcanic and sedimentary rocks of Ji’an Group,and the granites of the Tonghua area of the Liaoji rift zone by the LA-ICP-MS zircon U-Pb dating are studied in the paper.The results show that the Ji’an Group formed in 2 156 to 2 189 Ma,and subsequently underwent regional metamorphism between 1 870 and 1 881 Ma.Accompanied by the volcanic-sedimentation and the metamorphism of the Ji’an Group,two periods of granitic intrusions occurred;one was at 2 156 to 2 189 Ma during the rifting stage,whereas the other at 1 870 to 1 881 Ma during the orogenic period.In addition,ages of mag-matic zircons from the detrital zircons and the inherited zircons peaked at 2 471 to 2 494 Ma and 2 633 to 2 653 Ma,representing two magmatic events of the crystalline basement.Sedimentary provenance of the Ji’ an Group was derived from the Archean basement and products of the magmatism during the rifting events.
Keywords：Tonghua areaJi’ an GroupgeochronologyzirconLA-ICP-MS dating
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：13( 1487-1499 )