岩矿测试2012，Vol.31Issue(3)：543-548,6.
赣南兴国田新白垩纪火山岩的锆石U - Pb定年及其构造背景
Tianxin Cretaceous Volcanic Rock in Xingguo, South Jiangxi:Zircon U-Pb Dating and Its Tectonic Setting
摘要
Abstract
The Nanling area is famous for its widely distributed granites. There are also many volcanic rocks there, but cretaceous volcanic rocks are rare. In this paper, based on field survey, we investigate the rock formation time of Tianxin andesitic-porphyrite by Laser Ablation-Multicollector Inductively Coupled Plasma-Mass Spectrometry (LA-MC-ICPMS) zircon U-Pb dating, and determine its age to be (102. 3 ±0. 5) Ma. This result indicates that the stratum relation considered before should be adjusted, the Tianxin andesitic-porphyrite must have erupted in the late Cretaceous but not the late Jurassic period, the included sandstone breccia belongs to the early cretaceous Ganzhou group and the stratum covering on the andesitic-porphyrite belongs to the Nanxiong group, not the Ganzhou group. However, this result also indicates that, in this area, the magma activity from early to late was a reverse evolution from acid to neutral to mafic-ultra mafic during the Yanshanian period, and this might be related to the magma activity of the deep mantle, and possibly a production of tectonic event in the South China continental crust from thickening to thinning.关键词
田新安山玢岩/LA-MC-ICPMS锆石U-Pb定年/岩浆逆向演化/地幔深部Key words
Tianxin andesitic-porphyrite/ LA-MC-ICPMS zircon U-Pb dating/ magma reverse evolution/ deep mantle分类
天文与地球科学引用本文复制引用
陈振宇,王登红,陈郑辉,侯可军,赵正..赣南兴国田新白垩纪火山岩的锆石U - Pb定年及其构造背景[J].岩矿测试,2012,31(3):543-548,6.基金项目
中国地质大调查项目“南岭地区岩浆岩成矿专属性研究”(1212011120989) （1212011120989）
“我国重要矿产和区域成矿规律研究”项目(1212010633903) （1212010633903）
国家深部探测技术与实验研究专项“南岭成矿带地壳岩浆系统结构探测实验”(SinoProbe 0301) （SinoProbe 0301）
“南岭于都—赣县矿集区立体探测技术与深部成矿预测示范”课题(201011048) （201011048）
