中天山北缘青铝闪石和多硅白云母的发现及其地质意义  

DISCOVERY OF CROSSITE AND PHENGITE ON THE NORTHERN MARGIN OF THE CENTRAL TIANSHAN MOUNTAINS AND ITS GEOLOGICAL SIGNIFICANCE

作　　者：崔可锐[1,2] 丁道桂[1,2] 邢乐澄[1,2] 

机构地区：[1]合肥工业大学资源系 [2]地矿部石油地质中心实验室

出　　处：《中国区域地质》1997年第1期26-31,共6页Regional Geology of China

摘　　要：新疆中天山北缘存在一条早古生代构造混杂岩带。在该带东段乌斯特沟和干沟混杂岩中，发现了蓝闪石类矿物和多硅白云母。经电子探针分析，蓝闪石类矿物为青铝闪石，形成时压力为６７×１０５ｋＰａ。测得多硅白云母的ｂ０值为９０４１Ａ，晶体结构式中的离子数Ｓｉ平均为３４３。这些高压矿物的发现为确定中天山北缘构造混杂岩带的变质相提供了确凿的证据。There exists an Early Paleozoic tectonic mélange zone on the northern margin of the Central Tianshan Mountains.The authors first found glaucophanic amphiboles and phengite in mélanges at Wusitegou and Gangou in the eastern sector of the zone.Electron microprobe analysis shows that the glaucophanic amphiboles are represented by crossite formed at a pressure of 6.7×10 5 kPa.The b0 value of the phengite is 9.041 and the ion number Si in its crystal structure averages 3.43.The discovery of theses high pressure minerals provides reliable evidence for the metamorphic facies of the tectonic mélange zone on the northern margin of the Central Tianshan Mountains,thus furnishing necessary information for the tectonic evolution and paleo plate motion of the Tianshan orogenic belt.

关 键 词：青铝闪石 多硅白云母 地质意义 天山 矿物 

分 类 号：P578.955[天文地球—矿物学] P578.959[天文地球—地质学]