本文關(guān)鍵詞： 高黎貢變質(zhì)巖帶 構(gòu)造特征 淡色花崗巖脈 U-Pb定年　出處：《巖石學(xué)報(bào)》2016年08期 　論文類(lèi)型：期刊論文

【摘要】：高黎貢構(gòu)造帶作為藏東三江地區(qū)大地構(gòu)造上的一條重要構(gòu)造帶,在印度-歐亞板塊碰撞過(guò)程中起著重要的調(diào)節(jié)作用,并被認(rèn)為是該地區(qū)發(fā)生"大陸逃逸"與地塊旋轉(zhuǎn)的西邊界。本文以高黎貢構(gòu)造帶中的深變質(zhì)巖為研究對(duì)象,通過(guò)對(duì)高黎貢變質(zhì)巖帶南段進(jìn)行詳細(xì)地構(gòu)造解析,發(fā)現(xiàn)其內(nèi)部廣泛發(fā)育一系列或順巖石面理、或切割面理分布的淡色花崗巖脈;并選取了5個(gè)淡色花崗巖脈樣品進(jìn)行鋯石U-Pb測(cè)年,這5個(gè)樣品的鋯石~(206)Pb/~(238)U年齡值主要分布于二個(gè)區(qū)間:68~40Ma和24~21Ma,并在45Ma左右形成一個(gè)巨大的峰值�；阡喪木巍⒕�(nèi)結(jié)構(gòu)和微量元素組成特征等方面進(jìn)行鋯石成因?qū)W分析,認(rèn)為本文所測(cè)試的5個(gè)淡色花崗巖脈樣品的鋯石為深熔作用過(guò)程中形成的鋯石;從而推測(cè)高黎貢變質(zhì)巖帶南段發(fā)生深熔作用并形成淡色花崗巖脈的時(shí)代主要集中于68~40Ma和24~21Ma。
[Abstract]:As an important tectonic belt in the Sanjiang area of eastern Tibet, the Goligon tectonic belt plays an important role in the process of the Indo-Eurasian plate collision. This paper takes the deep metamorphic rocks in the Goligong tectonic belt as the research object and makes a detailed structural analysis of the southern section of the Goligong metamorphic rock belt. It is found that a series of pale granite veins are widely developed in its interior. The zircon U-Pb dating was performed on five samples of pale granite veins. The zircon dating values of the five samples are mainly distributed in two sections: 68 ~ (40) Ma and 24 ~ (21) Ma. A huge peak value was formed at about 45Ma. The genetic analysis of zircon was carried out on the basis of the crystal shape, intracrystalline structure and trace element composition of the zircon. It is considered that the zircon of the five pinkish granite veins tested in this paper is zircon formed during the process of deep melting. It is inferred that the age of deep melting and the formation of pallor granite veins in the southern section of the Gaoligong metamorphic belt are mainly concentrated at 6840 Ma and 2421 Ma.
【作者單位】： 中國(guó)地質(zhì)科學(xué)院地質(zhì)研究所;中國(guó)地質(zhì)調(diào)查局成都地質(zhì)調(diào)查中心;中國(guó)科學(xué)院紫金山天文臺(tái);
【基金】：國(guó)家“973”項(xiàng)目(2015CB452601) 國(guó)家自然科學(xué)基金項(xiàng)目(41302170、41302157) 中國(guó)地質(zhì)調(diào)查局項(xiàng)目(1212010000150009、121201010000150007、1212011220412)聯(lián)合資助
【分類(lèi)號(hào)】：P588.121;P597.3
【正文快照】： 1.中國(guó)地質(zhì)科學(xué)院地質(zhì)研究所,北京1000372.中國(guó)地質(zhì)調(diào)查局成都地質(zhì)調(diào)查中心,成都6100813.中國(guó)科學(xué)院紫金山天文臺(tái),南京2100081.Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China2.Chengdu Center,China Geological Survey,Chengdu 610081,C，

本文編號(hào)：1489302