新疆地质
新疆地質
신강지질
XINJIANG GEOLOGY
2014年
3期
295-300
,共6页
西昆仑%塞拉加兹塔格岩群%地质特征%构造环境
西昆崙%塞拉加玆塔格巖群%地質特徵%構造環境
서곤륜%새랍가자탑격암군%지질특정%구조배경
Western Kunlun%Sailajiazitage Rock Group%Geologic features%Tectonic settings
塞拉加兹塔格群主要分布在柯岗断裂以东阿喀孜达坂-苏皮克牙一带,是塔里木南缘铁克里克陆缘地块的重要组成部分。主体为一套双峰式火山岩夹少量碳酸盐岩、碎屑岩建造,火山岩主要由玄武岩、石英角斑岩、角斑岩组成。采用LA-ICP-MS方法测定锆石U-Pb年龄值(841.6±2.1)Ma,反映其时代为青白口纪,代表塞拉加兹塔格岩群原岩生成年龄。从火山岩的沉积学、地球化学特征综合分析,火山岩形成于板内拉张后期近洋壳的陆缘裂谷构造环境。
塞拉加玆塔格群主要分佈在柯崗斷裂以東阿喀孜達坂-囌皮剋牙一帶,是塔裏木南緣鐵剋裏剋陸緣地塊的重要組成部分。主體為一套雙峰式火山巖夾少量碳痠鹽巖、碎屑巖建造,火山巖主要由玄武巖、石英角斑巖、角斑巖組成。採用LA-ICP-MS方法測定鋯石U-Pb年齡值(841.6±2.1)Ma,反映其時代為青白口紀,代錶塞拉加玆塔格巖群原巖生成年齡。從火山巖的沉積學、地毬化學特徵綜閤分析,火山巖形成于闆內拉張後期近洋殼的陸緣裂穀構造環境。
새랍가자탑격군주요분포재가강단렬이동아객자체판-소피극아일대,시탑리목남연철극리극륙연지괴적중요조성부분。주체위일투쌍봉식화산암협소량탄산염암、쇄설암건조,화산암주요유현무암、석영각반암、각반암조성。채용LA-ICP-MS방법측정고석U-Pb년령치(841.6±2.1)Ma,반영기시대위청백구기,대표새랍가자탑격암군원암생성년령。종화산암적침적학、지구화학특정종합분석,화산암형성우판내랍장후기근양각적륙연렬곡구조배경。
The stratum of Sailajiazitage Group distributes from Akazidaban to Supikeya, located to the east of Kegang fault,which is also an important part of Tiekelike epicontinental massif in the south edge of Tarim block.Its composition are mainly bimodal volcanic rock,which contains small amounts of carbonate rock,and pyroclastic rock.And the volcanic rock is composed of basalt, quartz keratophyre and keratophyre.By means of LA-ICP-MS U-Pb dating of the zircon from quartz keratophyre in the Sailajiazitage Group,an age of (841.6 ± 2.1) Ma is determined,which should be the Qingbaik-ouan Period,and stands for the original rock age of the Sailajiazitage Rock Group.The sedimentology and geochemistry features of the volcanic rock indicate that,the volcanic rock in Sailajiazitage Group is formed under the tectonic environ-ment of epicontinental rift valleys in the later period of intraplate’s tension.