| 河南中部晚太古代登封群和太华群成岩构造环境和区域变质带的讨论 |
| |
| 关键词: |
| 基金项目: |
|
| 摘要点击次数: 4558 |
| 全文下载次数: 4780 |
| 摘要: |
| ON THE TECTONIC ENVIRONMENTS AND METAMORPHIC BELTS OF THE LATE ARCHEAN DENGFENG GROUP AND TAIHUA GROUP FROM CENTRAL HENAN,CHINA |
| The Dengfeng Group and Taihua Group of Late Archean from central Henan show a unique feature of rock formation and protolith association which cannot be simply compared with those of the greenstone belts in the other part of the world. In general, the rock formation and protolith association of the Dengfeng Group reflect the development history of an island arc region, while those of the Taihua Group reflect the development history of an ancient tiench arc-trench gap region. These two groups can be related in terms of plate tectonic theory.The central Henan is divided into three metamorphic belts. The Songshan -Xuchang metamorphic belt corresponds to the medium temperature-medium pressure amphibolite facies with metamorphic temperatures of 475-500℃ and pressures of 4.5-7.0kb. The Jishan-Beiwudu metamorphic belt probably corresponds to the low temperature greenschist-epidote amphibolite facies, although its metamorphic pressures still remain undetermined. The Lushan-Wuyang metamorphic belt corresponds to the high temperature-low pressure amphibolite facies with metamorphic temperatures of 620-625℃ and pressures around 4 kb.These three metamorphic belts are arranged in order of southward direction. First two metamorphic belts are found in Dengfeng Group and probaly belong to the same medium pressure metamorphic belt with symmetric texture included in an island arc series; whereas the last metamorphic belt occurs in Taihua Group which had lay to an ancient trench or arc-trench gap region and due to special tectonic environments (thin crust, high temperature, little plate, steep subduction belt and slow subduction speed etc.), it results in a low pressure-high temperature amphibolite facies metamorphic belt instead of high pressure-low temperature glaucophane-schist belt. |
| TU Shao-xiong.1984.ON THE TECTONIC ENVIRONMENTS AND METAMORPHIC BELTS OF THE LATE ARCHEAN DENGFENG GROUP AND TAIHUA GROUP FROM CENTRAL HENAN,CHINA[J].Acta Geoscientica Sinica,6(1):39-56. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
|
|