摘要
造山带一般都经历了多期板块裂解与拼合的复杂演化过程。造山带地层体在造山带洋盆会聚、俯冲消亡和陆内造山阶段,发生过强烈的构造搬运和构造混杂。俯冲带在消减板块下潜过程中,盆地中先前在重力机制下形成的原始浊积岩和远洋沉积(基质)、同沉积滑塌岩块,与先前在热力机制下形成的蛇绿岩和火山弧,与早先裂解的陆壳碎片等最终一并带入俯冲带内遭受剪切,发生构造混杂,由这种混杂作用形成的地层体通常由经强烈构造剪切作用的基质(浊积岩和远洋沉积)和混入的多种外来岩片(块)构成,是造山带非史密斯地层研究的主体。对造山带非史密斯地层,要针对基质和外来岩片(块)分别进行划分、对比研究。特别对基质中的外来岩片(块),要进行物态、时态,相态、位态、变形和变质历程的精细解剖与研究。通过造山带非史密斯地层研究,建立造山带地层系统理论模型,恢复造山带形成和演化历程。
Orogenic belts always underwent complex geological evolution process, characterized by multiple cracking and splitting of plates. During the ocean basin convergence, subduction and intra-continental orogeny, the strata underwent dramatic tectonic migration and mixing. In the process of plate subduction, the previously formed original turbidite under gravity mechanism, ocean deposits, and synsedimentary slumped rock mass, with the ophiolite and volcanic arc that were formed by the thermo-dynamic mechanism, and with the fragments of the cracked continental crust, etc., were eventual[y brought into the subduction zone and mixed and sheared. This mixed body which usually formed with matrix （turbidite and ocean deposits） having undergone strong tectonic shearing action and with a variety of foreign rock slices （blocks） is the main body of the research of the orogen non-Smithian strata. In the study of orogen non-Smithian strata, the division and comparison research of the matrix and foreign rock slices （blocks） should be carried out separately. Especially for the foreign rock slices （blocks）, we must carry on the careful dissection and research of their physical states, tenses, phase states, position states, deformation and metamorphic processes. Through the study oforogen non-Smithian strata, the theoretical model of orogenic stratigraphic system can be established, and then the history of formation and evolution of orogenic belts can be restored.
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2014年第2期36-47,共12页
Earth Science Frontiers
基金
中国地质调查局资助项目(1212011121036
12120113012500
12120113023200)
关键词
造山带
大地构造相
非史密斯地层
造山带地层系统理论模型
orogenic belt
tectonic facies
non-Smithian strata
theoretical model of orogenic stratigraphic system
