摘要
内蒙古旗下营北部伸展构造是90年代中晚期进行1∶5万区调时识别确定的。标志性构造形迹拆离断层产状平缓,倾角10°～15°,其间发育黄白色或蛋青色微角砾岩、假玄武玻璃、断层泥等构造岩。下盘由太古宙变质岩系和早白垩世二长花岗岩组成,均发育近水平韧性剪切带,花岗岩宏观上呈层状产出。上盘岩系组成较复杂,有的地段为下白垩统李三沟组和固阳组,发育构造劈理带及高角度正断层;有的地段则为中元古界渣尔泰山群、古元古界二道洼岩群及太古宙大理岩,韧性变形显著,呈糜棱岩或构造岩片形式产出。
The extensional structure in the Shenshuiliang area in the northern part of Qixiaying,Inner Mongolia,was recognized during1∶50000regional surveys in the area in the middle and late1990s.The detachment fault dips gently at10～15°,in which there occur such tectonites as yellowish white or egg-green microbreccia,pseudotachylite and fault gouges.The footwall consists of Archean metamorphic series and Early Cretaceous monzogranite,where subhorizontal ductile shear zones are developed;macroscopically granite shows layering.The rock series in the hanging wall is complex.In some places the rock series is represented by the Lower Cretaceous Lisangou and Guyang Formations ,in which there occur tectonic cleavage zones and high-angle normal fault systems ,forming a number of tilted fault blocks.In other places the rock series consists of the Mesoproterozoic Zha'ertaishan Group,Paleoproterozoic Erdaowa Group-complex and Archean marble;ductile deformation is conspicuous ,manifested by the occurrence of mylonite,and marble is flaky.
出处
《地质通报》
CAS
CSCD
北大核心
2002年第4期259-263,共5页
Geological Bulletin of China
基金
内蒙古察右中旗全盆地区1:5万区调等项目成果之一。
关键词
内蒙古
伸展构造
拆离断层
构造形迹
糜棱岩
形成时代
Qixiaying
Inner Mongolia
regional survey
extensional structure
detachment fault
