摘要
甘肃敦煌－北山地区广泛出露早前寒武纪岩石。这些岩石在早期的《甘肃省区域地质志》中被确定为前长城系、长城系、奥陶－志留系及部分石炭系。本文认为这些岩石应属太古宙和古元古代。据此，重新厘定了该区早前寒式纪岩石－构造框架。自南向北划分为敦煌太古宙杂岩区、北山南带古元古代剪切构造区和北山北带古元古代－太古宙杂岩区，并根据变形特点和岩石组合，进一步划分出次级带。
Early - Precambrian rocks are widely exposed in Dunhuang-Beishan area, GansuProvince. The Precambrian rocks are traditionally defined as strata of Pre-Changchengian,Ordovician-Silurian, Carboniferous and Baihu Group. According to field investigation, the rocksare reinterpreted as Aichaean and Palaeoproterosoic ages. They can be divided into three terrainsfrom south to north: Dunhuang mctamorphic terrain, south Beishan palaeoproterozoic tectonicterrain and north Beishan Archaean-Palaeoproterozoic terrain. These terrains can be furtherdivided into litho-structural zones(belts) according to deformation ard metamorphism, that is:Hongliuxia-Dunhuang Metasedimentary Belt, Anxi-Cijin TTG Belt, Baidunzi-Qiaowan Shearsone within the Dunhuang terrain; Xiaoxigong-Sishilijing Palaeoproterozoic shear zone andYamajie-Mazongshan Palaooproterozoic Shear zone within the south Beishan.
出处
《前寒武纪研究进展》
1997年第4期47-54,共8页
Progress in Precambrian Research
基金
"九五"地矿部资源与环境科技攻关课题!95-02-011-02
