地质学报2012，Vol.86Issue(7)：1063-1076,14.
青藏高原西北缘红其拉甫岩体的岩石成因、时代及其构造意义
The Age and Origin of the Konjirap Pluton in Northwestern Tibetan Plateau and Its Tectonic Significances
摘要
Abstract
crystallization of plagioclase, apatite and ilmenite. The high CaO, high CaO/Na2O ratio, depletion of Nb and Ta, low Mg# , enriched K, and Sr isotope all show that the pluton was dervided from remelting of the amphibole facies basaltic rocks in lower crust. The low Y and HREE, high A12O3 and Sr, and low Sr/Y ratio, and the diagrams of SiO2-Mg# , SiO2-Al2O3, along with the structure of intergrowth between quartz and alkali feldspar, indicate that the pressure of the source region may be >1. 5 GPa (the thickness of crust was 50 km at least). The initial temperature of magma was > 788℃ using calculation of the saturation temperatures and structure, and U-Pb isotopes analysis of zircon, and is in accordance with the temperature and pressure conditions of formation of the granite with high Sr and low Yb(adakite) , and the residual facies is correspondingly garnet + amphibole + rutile (with no plagioclase). Based on the regional geological data, the pluton should be the product of thickening crust which was caused by the collision between Gangdese massif and Qiangtang massif with the closing of Bangonghu-Nujiang ocean, it is suggested that the closure times of western and central eastern Bangonghu-Nujiang ocean should be the same.关键词
青藏高原西北缘/红其拉甫岩体/锆石U-Pb年龄/岩石成因/构造意义Key words
northwestern Tibetan Plateau/ Konjirap pluton/ zircon U-Pb geochronology/petrogenesis/ tectonic significances引用本文复制引用
康磊,校培喜,高晓峰,朱海平,奚仁刚,过磊,董增产..青藏高原西北缘红其拉甫岩体的岩石成因、时代及其构造意义[J].地质学报,2012,86(7):1063-1076,14.基金项目
本文为陕西省自然科学基金(编号2012JM5004)和中国地质调查局国土资源大调查研究项目"西昆仑—阿尔金成矿带基础地质综合研究"(编号1212011085034)联合资助的成果. （编号2012JM5004）
