桐柏北部条山—朱庄一带秦岭褶皱带古构造环境初探  

A PRELIMINASY STUDY CON THE PALEQTECTONIC SETTINGOF THE QINLING FOLO BELT ALONG TIAOSHANZHUZHUANG AREA IN THE NORTHERN PARTOF THE TONGBAI MOUNTAINS

作　　者：康伯凯 马文璞[2] 

机构地区：[1]中国地质大学 [2]北京大学

出　　处：《现代地质》1989年第1期91-101,共11页Geoscience

摘　　要：条山—朱庄地区位于秦岭褶皱带的北带,其目前的研究程度还很低。本文对这一地区的野外地质特征和岩石化学的研究表明,该地区中部的红石山和黑石山之间早古生代的斜长角闪岩原岩可能主要为玄武岩;而两侧的变粒岩原岩可能主要为长石砂岩和长石石英砂岩,斜长角闪岩的原岩可能主要为泥灰岩。进而通过火山岩系列分析、岩石化学图解、微量和稀土元素地球化学分析、花岗岩判别图解、矿物组分和岩性分布格局的研究,认识到中部的早古生代玄武岩属于钙碱系列,并与区内早古生代侵入岩体组成的深成杂岩体共同构成火山—深成杂岩带;中部地段在早古生代发育时的古构造环境可能是岛弧环境,古岛弧所处的位置相当于现在桃园岩体的南东地段,古岛弧在后期遭受强烈的侵蚀作用,使得深部杂岩体得以露出地表,同时也成为两侧沉积盆地的蚀源区。因此,该地区两侧地段早古生代的古构造环境可能是发育于岛弧两侧的沉积盆地。Tiaoshan and Zhuzhuang area is situated on the northern part of the Pin-ling Fold Belt.It is indicated in this paper,through the analysis of field geological characters and petrochemistry, that the original rock of the early Paleozoic amphibolite which lies between the Hongshi mountain and the Heishi mountain that is situated in the middle part of this area comes from basalt.that the original rock of granulite and amphibolite in the two Parts beside the middle part probably is arkose and marl. Furthermore,the petrochemical data of volcanic series and lithological distributions show that the early Paleozoic basalt in the middle part belongs to the calcic-lkalic series and forms a volcanic-lutonic complex, that the early paleozoic tectonic environment of the middle part probably is island arc which is being strongly eroded. The erosion leads to the cropping out of the deep plutonic complex which,afterwards,become the material source of the two parts beside the middle part in this area, The early Paleozoic tectonic environment of the two parts beside the middle part probably is sedimentary basin beside the island arc.

关 键 词：秦岭褶皱带 原岩 岩石化学 古岛弧 岛弧环境 

分 类 号：P5[天文地球—地质学]