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东南极普里兹带是一条经受格林维尔期和泛非期高级构造热事件影响的多相变质带,其构造演化过程与罗迪尼亚和冈瓦纳超大陆的形成密切相关。新的岩石学和年代学资料表明,普里兹带中的格林维尔期高级变质作用是区域性的,并经历了>970Ma和930～900Ma两个演化阶段(期),变质条件达到相对高温高压的麻粒岩相。格林维尔期造山作用起始于活动大陆边缘或岛弧环境下的岩浆增生,最后发展到陆陆碰撞,从而使印度、东南极西陆块和非洲的卡拉哈里克拉通拼合在一起,构成了罗迪尼亚超大陆的重要组成部分之一。普里兹带中的泛非期高级变质作用并不象前人认为的那样只发生在中低压麻粒岩相条件下,而是达到高压麻粒岩相,并具有近等温减压的顺时针P-T演化轨迹。格林维尔期变质先驱的普遍存在说明泛非期碰撞造山事件主要叠加在印度-南极陆块东缘的基底杂岩之上,所以其主缝合线的位置应该在现今普里兹带的东南方向,并可能向南极内陆延伸到甘布尔采夫冰下山脉。对不同类型岩石的精细定年揭示,普里兹带中泛非期造山作用过程从570Ma一直持续到490Ma,这与东非造山带的晚期碰撞阶段大致相吻合。因此,冈瓦纳超大陆的最后拼合可能是通过西冈瓦纳、印度-南极陆块和澳大利亚-南极陆块等三个陆块的近于同期碰撞来完成的。
The Pryz Belt in Southeast Antarctica is a multi-metamorphic belt that has been subjected to the Greenville and Pan-African high-tectonic thermal events and its tectonic evolution is closely related to the formation of the Rodinia and Gondwana supercontinent. New petrological and geochronological data indicate that the Upper Greenville period metamorphism in the Przewalski stratigraphic zone is regional and has experienced two stages of evolution (> 970 Ma and 930-900 Ma) with metamorphic conditions reaching relatively high temperature and high pressure Granulite facies. The orogeny of the Greenville period started with magmatic propagation under the active continental margins or island arcs and finally progressed to land-continent collisions, bringing the Indian, East-West polar continent and the Kalahali Craton of Africa together to form Roddy One of the most important parts of the Nia super continent. The Pan-African high-grade metamorphism in the Prydzelt does not occur only under conditions of moderate-low-pressure granulitic facies, as previously thought, but reaches a high-pressure granulitic facies with a clockwise, nearly isothermal, decompression PT evolution trajectory. The prevalence of the pioneers of the Greenville period indicates that the Pan-African orogenic collision was mainly superimposed on the basement complex on the eastern edge of the Indian-Antarctic terrain so that its main suture should be located in the southeast direction of the current Pridz belt, And may extend inland to Antarctica to the Gandoults ice patch range. The fine dating of different types of rocks revealed that the process of Pan-African orogenic orogenic processes in the Prydz belt continued from 570 Ma to 490 Ma, roughly in accordance with the late collision stage of the East African orogenic belt. As a result, the final assemblage of the Gondwana supercontinent may have been achieved through the near-simultaneous collision of three land blocks, namely, the West Gondwana, the Indian-Antarctic landmass and the Australian-Antarctic landmass.