自然杂志 ›› 2007, Vol. 29 ›› Issue (5): 255-264.

• 专题综述 • 上一篇    下一篇

超高压变质作用:地球科学的新热点

游振东   

  1. 中国地质大学,武汉 430074
  • 收稿日期:2007-09-13 修回日期:2007-09-13 出版日期:2007-10-25 发布日期:2007-10-25

Hot-Spot in Earth Science

YOU Zhen-dong   

  1. China University of Geoscience, Wuhan 430074
  • Received:2007-09-13 Revised:2007-09-13 Online:2007-10-25 Published:2007-10-25

摘要: 超高压质作用是变质压力达2.5Gpa 以上的超深变质作用。以出现柯石英、金刚石等超高压变质矿物为标志。我国大别苏鲁是世界上出露最好、延伸最长的超高压变质带。代表中晚三叠纪扬子陆块向中朝陆块深俯冲过程中巨量陆壳物质曾经进入地幔深度达150Km.超高压变质的形成和折返、隆升岩石记录的精细研究,可以获得变质的PT轨迹,进而重塑“先挤压、后拉张”的构造演化模型。超高压变质作用的研究为板块构造理论在大陆的应用,展开新前景,已经成为地球科学的新热点之一。

关键词:

超高压变质作用, 碰撞造山带, 大别苏鲁, 深俯冲, 隆升与折返, 大陆动力学

Abstract: Ultrahigh- pressure (UHP) metamorphism refer to those metamorphic pressure is higher than 2.5Gpa because of ultradeep conditions. Coesite , metamorphic diamond and other UHP mineral or mineral assemblages typify their collisional origin. In China, Dabie—Sulu collisional orogenic belt developes the most well-exposed and largest in scale UHP metamorphic belt in the world. The development of the UHP metamorphic belt indicates that in the mid –Triassic time the Yangtze craton was deeply subducted beneath the Sino-Korea craton implying that voluminous crustal materials had deeply subducted to a mantle-depth up to 150Km. The careful study of those petrological records remained in the UHP metamorphic rocks reveals their formation, uplift and exhumation processes. From these information the metamorphic PT path and an” active compression and then active extension” 4-stage tectonic evolution model can be reconstructed. Therefore, the study of UHP metamorphism had provided new prospect for the theory beyond plate tectonics onward the continents. And UHP metamorphic study had become a new hot-spot in the field of Earth science.

Key words: Ultrahigh-pressure metamorphism, collisional orogenic belt,Dabie-Sulu,deep subduction,uplift and exhumation,continental dynamics