地质通报2012，Vol.31Issue(12)：1939-1948,10.
西天山尼勒克地区浅成花岗质侵入体的地球化学特征及形成时代
Geochemistry and dating of the hypabyssal granite body in Nilka County of Western Tianshan Mountains
摘要
Abstract
Granodiorite porphyrite and granite porphyry are respectively exposed in Yilanbasitao and Wulangdaban of western Nilka County, Xinjiang. Detailed petrologic and geochemical studies have shown that the two rock bodies are characterized by weak peralu-minous nature, rich Na and LREE, deficiency of HREE and weak positive Eu anomalies, geochemically similar to adakite rocks in such aspects as rich Na2O and A12O3, high Sr, low Yb and Y, and loss of HREE. Zircon U—Pb dating shows that ages of the two rock bodies are respectively 291.8Ma±3.7Ma (MSWD=1.13) and 303.6Ma±4.0Ma (MSWD=0.95), suggesting a period from the end of late Carboniferous to the beginning of early Permian. According to their petrological and geochemical characteristics as well as regional geological evidence, the authors have reached the conclusion that the two granite bodies are products of magmatic invasion at the continental extension stage after the closure of Tianshan Paleozoic oceanic basin, and that they were formed by partial melting of the lower crust.关键词
西天山/尼勒克/浅成花岗质侵入体/地球化学/形成时代Key words
Western Tianshan Mountains/Nilka/hypabyssal granite/geochemical features/formation age分类
天文与地球科学引用本文复制引用
李晓英,徐学义,孙吉明,李智佩,白建科,张晓博..西天山尼勒克地区浅成花岗质侵入体的地球化学特征及形成时代[J].地质通报,2012,31(12):1939-1948,10.基金项目
中国地质调查局项目《天山-兴蒙成矿带火山岩浆作用对成矿制约的综合研究》(编号:1212011085475)、《天山成矿带基础地质综合研究》(编号:1212011085055)和《西北综合研究》(编号:1212011220649) （编号:1212011085475）
