地质力学学报2016，Vol.22Issue(4)：1015-1031,17.
西南天山乌什县晚三叠世镁铁-超镁铁质层状杂岩体年代学及地球化学研究
GEOCHRONOOGICAL AND GEOCHEMICAL STUDY OF THE LATE TRIASSIC LAYERED MAFIC-ULTRAMFIC INTRUSIONS IN BEISHAN AREA OF WUSHI COUNTY,SOUTHWEST TIANSHAN
摘要
Abstract
Layered Mafic-ultramafic intrusions,which carry abundant information of mantle and provide an excellent approach to probe the mantle material composition,plate tectonic and deep geological process,are generally considered to be an important symbol of lithosphere extension,We discovered a suit of layered Mafic-ultramafic intrusions in Southwest Tianshan area,and obtained the zircon U-Pb age of gabbros of 224 ± 4 Ma.These rocks are characterized by the enrichment of LREE,H2O,Na2O + K2O and incompatible elements such as Th,U,Nb,Ta,etc.,and depleted in HREE.They might be derived from enriched mantle,which is formed by low degree partial melting of garnet lherzolite.The primary magma may be high Mg basaltic magma which was rich in iron and titanium and mainly controlled by the fractional crystallization.This magam in the continental orogenic stage was actived in the environment of intracontinent orogen after the closure of the South Tianshan ocean and post collisional orogeny,which derived from mantle in the envirnment of extensional environment.We can concluded that the Southwest Tianshan area was under an extensional tectonic seting during late Triassic.关键词
西南天山/镁铁-超镁铁质/层状杂岩Key words
Southwest Tianshan area/mafic-ultramafic/layered intrusions分类
天文与地球科学引用本文复制引用
胡朝斌,李培庆,辜平阳,陈锐明,查显锋,庄玉军..西南天山乌什县晚三叠世镁铁-超镁铁质层状杂岩体年代学及地球化学研究[J].地质力学学报,2016,22(4):1015-1031,17.基金项目
中国地质调查局地质调查项目“特殊地质地貌区填图试点”(DD20160060)、“新疆1:5万喀伊车山口等3幅艰险区试点项目”(12120114042701)、“东昆仑成矿带木孜塔格铅锌铜金多金属矿调查评价区地质矿产调查”(DD20160002) （DD20160060）
