摘要
北淮阳构造带位于大别造山带北缘 ,其中东段安徽境内变质构造地层佛子岭岩群对北淮阳带区域构造研究至关重要。研究表明 ,以原黄龙岗岩组为界 ,佛子岭岩群上、下部早期构造变形明显不同。佛子岭岩群下部郑堂子岩组、仙人冲岩组、祥云寨岩组发育以固态流变为特征的褶叠层构造 ,形成于地壳伸展构造体制下 ,是横向构造置换作用的产物。佛子岭岩群上部诸佛庵岩组、八道尖岩组、潘家岭岩组表现为纵弯褶皱变形 ,构造置换不彻底 ,局部保留有原生沉积结构构造 ,形成于地壳收缩构造体制下 ,是纵向构造置换作用的产物。因此 ,文中将原佛子岭岩群解体为下部卢镇关构造混杂岩带和上部诸佛庵岩群 。
Beihuaiyang tectonic belt lies in the northern margin of the Dabie Mountains. The Foziling lithogroup, one of the metamorphic tectono-stratigraphic units in the eastern part of the belt, is the key to a better understanding of the evolution of the Beihuaiyang tectonic belt. The Huanglonggang lithoformation occurred as a tectonic boundary zone which separates the upper part of the Foziling lithogroup from the lower part of the same Lithogroup. The upper part differs from the lower part in many aspects, such as in metamorphism and in deformation. The lower part of the Foziling lithogroup is composed of Zhengtangzi, Xianrenchong and Xiangyunzhai lithoformations. It's characterized by the development of the intra-folds, which is interpreted as the result of extensional tectonic deformation. The deformations in the lower part indicate an extensive tectonic replacement. In contrast, the upper part of the Foziling lithogroup, which consists of Zhufoan, Badaojian and Panjialing lithoformations, is dominated by buckling deformation, which is thought to be the result of contraction in crust. Based on our study, we propose to divide the former Foziling lithogroup into two lithogroups: The lower part named as Luzhenguan melange and the upper part Zhufoan lithogroup. The former Huanglonggang lithoformation is identified as a horizontal ductile detachment shear zone.
出处
《地学前缘》
EI
CAS
CSCD
2004年第3期83-90,共8页
Earth Science Frontiers
基金
国家自然科学基金资助项目 (4 990 2 0 1 7)
关键词
北淮阳构造带
变质构造地层
佛子岭岩群
构造变形
Beihuaiyang tectonic belt
metamorphic tectono-stratigraphy
Foziling lithogroup
deformation
