doi:10.16186/j.cnki.1673-9787.2020040060

Received:2020/04/15

Revised:2020/05/20

Published:2021/11/15

Zircon U-Pb dating and geological significance of Xiaoqinling Xiaohe pluton in the southern margin of North China

PANG Xucheng1, HAN Di1, ZONG Rui2, DUAN Qichao1, ZHANG Yan2, ZHANG Xin1

1.Institute of Resources and Environment， Henan Polytechnic University， Jiaozuo  454000 ， Henan， China;2.No.， Bureau of Geology and Miniral Exploration and Development of Henan Province， Zhengzhou  450000 ， Henan， China

Abstract:Xiaohe pluton is one of the four large-scale granites in the Xiaoqinling area ， southern margin of North China. The existing rock age data are still insufficient. In order to accurately determine the age of Xiaohe pluton ， based on the determination of intrusive periods in the field ， the granite was sampled and purified by zircon ， and then U-Pb dating was carried out by LA-ICP-MS. Most of the samples were located at or near the3Pb，/2U-"Pl/""U consistent line. The dating data showed that the crystallization age of Xiaohe granite was（1 795 ±70） Ma， which was in the late Zhongtiao orogeny. In the middle and late period of Xiong' er ， it was subjected to a large scale of metamorphism and dike invasion. Afterwards ， although the multi-stage tectonomagmatism formed the multi-stage dikes interpenetrating into the rock mass ， the scale and strength were limited. It showed the development process of regional magmatic activity from inoculation intrusion-strong eruption-energy weakening to intrusion. There was a huge time difference between the pluton formation and the regional gold and silver mineralization， so it was speculated that the contribution to regional metallogenic process was limited.

Key words:Xiaohe pluton;zircon U-Pb dating;geological significance;Xiaoqinling;southern margin of North China

 华北南缘小秦岭小河岩体锆石U-Pb定年及地质意义_庞绪成.pdf