Distribution domains of the Pan-African event in East Antarctica and adjacent areas
Distribution domains of the Pan-African event in East Antarctica and adjacent areas
复制标题
泛非事件在东南极及邻近地区的分布域
DOI：
10.13679/j.advps.2018.2.00087
复制
发表时间：
2018
影响因子：
--
通讯作者：
Ren Liudong
中科院分区：
文献类型：
--
作者：
Ren Liudong
从剪切带、花岗岩、伟晶岩、高变质期和碎屑锆石等方面分析，泛非事件广泛分布于东南极洲（EA）克拉通中，既包括沿海地区，也包括EA内部。内陆下流沉积物的年龄峰值，EA的泛非事件和冈瓦纳的邻近地区。本文描述了非洲东南部、印度南部和澳大利亚西南部的重建情况。水或液体可用沿。剪切带是早期（如Grenville时代）、高等级露头到晚期泛非洲的退退的主要原因。角闪岩-麻粒岩相变质作用。在地球化学上，花岗岩一般为造山花岗岩，偶有一些。辉长岩或白云岩岩脉，呈双峰特征。同时，这一事件影响了大多数同位素系统。包括U-Pb、Sm-Nd、Rb-Sr和Ar-Ar系统，给出了泛非的表观年龄。在空间上，泛非事件表现为从可能是局部的花岗质岩浆作用，到更广泛的中-高变质作用，主要分布于。某些同位素系统的重置，表明该事件的主要热效应。在冈瓦纳形成之前，EA的局部洼地可能已经充满了沉积物，这意味着罗迪尼亚的初始破碎期。后来的。泛冈瓦纳逆旋齿形形成了陆块间的间隙褶皱带，形成了一套剪切带。冈瓦纳的基性基底可能是泛非事件的典型特征的原因。该事件。在构造机制上可能是一种压倒性的伸展和横向构造，可能是板块的响应。围绕大陆的运动聚集在尚不稳定的冈瓦纳大陆内部。
The Pan-African event is widely distributed in East Antarctica (EA) craton, including both the coastal regions and.interior of the EA. From aspects of the shear zones, granites, pegmatites, time of high-grade metamorphism and detrital zircon.age peaks of the downflowing sediments from the inland, the Pan-African event in the EA and adjacent areas in the Gondwana.reconstruction, like SE Africa, southern India and SW Australia, was described in the paper. The water or fluid available along.the shear zones was responsible for retrogression of the earlier, e.g., Grenville age, high-grade outcrops to later Pan-African.amphibolite to granulite facies metamorphism. In geochemistry, the granites are generally anorogenic, ocassionally with some.gabbros or dolerite dykes, showing sign of bimodal feature. Meanwhile, the event has influenced most isotopic systems,.including the U-Pb, Sm-Nd, Rb-Sr and Ar-Ar systems, giving Pan-African apparent ages. Spatially, the Pan-African event is.demonstrated from possibly local granitic magmatism, to wider medium-high grade metamorphism, and mostly widespread in.resetting for some isotope systems, suggesting the prevailing thermal effect of the event. Before Gondwana formation, local.depressions in the EA may have been filled with sediments, implying the initial breakup period of the Rodinia. The later.Pan-Gondwana counterrotating cogs shaped the interstitial fold belts between the continent blocks and formed a set of shear.zones. The mafic underplating in the Gondwana may be responsible for the typical features of the Pan-African event. The event.may be an overwhelmingly extensional and transcurrent tectonics in mechanism and is a possible response of the plate.movement surrounding the continent swarms in the non-stable interior of the yet consolidated Gondwana.