DISCUSSION ON THE NEOARCHEAN GEOLOGICAL EVOLUTION IN ANSHAN-BENXI-FUSHUN REGION
-
摘要: 鞍山-本溪-抚顺地区是我国太古宙岩石出露的主要地区及重点研究区.区内太古宙岩石以变质深成侵入体为主，变质表壳岩出露面积不足20%.区内变质深成岩侵位于始太古代-新太古代的不同时期，原岩由TTG岩系和钙碱性CA岩系组成；变质表壳岩以磁铁石英岩和斜长角闪岩为标志性岩性.两类原岩建造在太古宙时期，遭受了由麻粒岩相到角闪岩相至绿片岩相连续降温减压过程.根据区内新太古代岩石出露的特点划分3个微古陆核，分别为鞍本古陆核、清原古陆核及辽北古陆核.中太古代和新太古代为本区最重要的造陆时期，以鞍本微古陆核为最早的增生点，经拼接增生、裂解改造，形成现今的地质格局.Abstract: Anshan-Benxi-Fushun is the main outcropped area and key study area for Archean rocks in China, where the metamorphic plutonic intrusion is dominant while the outcropped metamorphic supracrustal rocks are less than 20% by area. The metamorphic plutonic rocks are emplaced in different periods of the Eoarchean-Neoarchean, with the protolith composed of TTG and CA rock series. The typical metamorphic supracrustal rocks are magnetite quartzite and amphibolite. The protolith formations of the two types of rock experienced continuous temperature reduction and decompression process from granulite through amphibolite to greenschist facies in Archean. According to the outcropping characteristics of Neoarchean rocks, the authors divide the study area into three micro paleo-continent nucleuses, namely Anben, Qingyuan and Liaobei paleo-continent nucleuses. Mesoarchean and Neoarchean are the most important epeirogenetic periods, with the Anben micro paleo-continent nucleus as the earliest accretion center, going through matching and splitting transformation, then forming the current geological structure.
-
-
计量
- 文章访问数: 390
- PDF下载数: 94
- 施引文献: 0
下载: