地质与勘探2017，Vol.53Issue(5)：855-866,12.
东昆仑造山带早中生代幔源岩浆事件及其地质意义
Early Mesozoic Mantle-Derived Magmatic Events and Their Geological Significance in the East Kunlun Orogenic Belt
摘要
Abstract
The Early Mesozoic mantle-derived magmatic underplating in the East Kunlun orogenic belt provides not only energy and material for the extensive development of granites, but also a new constraint on determination of regional tectonic environments. In this paper, an accurate zircon U-Pb chronology study is carried out on the Xiaojianshan and Lalinggaoligounao intrusion, and a comparison is made with the mafic rock in the study area. The resultsofLA-ICP-MSU-Pbdatingshowthattheconcordiaageofzircon206Pb / 238U-207Pb /235Uis(247.1 ±1.1)Ma,whichis20Maolderthan the age of gabbro in previous work, indicating that the intrusion is the product of multi-stage magmatic activities. The zircon ages of the 206 Pb / 238 U-207 Pb/235 U for No. 2 and No. 3 intrusions are (244. 9 ± 1. 6) Ma and (238. 4 ± 4. 1) Ma, respectively. Based on the ages and geochemical character-istics of the known mafic rocks in the area, we suggest that the Early Mesozoic mantle magma was formed in the post-collision extensional environment with a time limit of 251~221 Ma. The mantle-derived magma of this period has experienced a wide material and energy exchange with crust, which is one of the important objects of copper-nickel exploration in the future.关键词
锆石U-Pb年龄/幔源岩浆/小尖山岩体/拉陵高里沟脑/东昆仑Key words
zircon U-Pb age/mantle-derived magma/Xiaojianshan intrusion/Lalinggaoligounao intrusion/East Kunlun分类
天文与地球科学引用本文复制引用
王亚磊,张照伟,张江伟,钱兵,刘月高,尤敏鑫..东昆仑造山带早中生代幔源岩浆事件及其地质意义[J].地质与勘探,2017,53(5):855-866,12.基金项目
国土资源部公益性行业科研专项项目(201511020)、国家自然科学基金(青年)项目(41402071,41302052)和中国地质调查局地质矿产调查项目(DD20160013)联合资助. （201511020）
