Deciphering the early Archaean crustal history in the Kaapvaal and Zimbabwe cratons

该项目将利用实地调查、单颗锆石测年、地球化学以及Hf和Nd同位素系统，调查津巴布韦和卡阿普瓦尔克拉通东部两个鲜为人知的地区最古老的地壳成分。在津巴布韦中部，我们的初步工作已经确定了几个花岗片麻岩的锆石年龄&3.6Ga，我们的目的是了解这些岩石所在地体的火成岩、构造和变质历史。在东部Kaapvaal克拉通，在斯威士兰中部的一块片麻岩地体内，我们将调查一套太古代麻粒岩相表壳岩石序列，其中含有碎屑锆石&Gt；3.6Ga以及周围的花岗岩类片麻岩，其中我们还预计有非常古老的地壳成分，目的是确定古代锆石的源区，并了解这一古老地体与斯威士兰古片麻岩杂岩和邻近的Barberton绿石带和Kaapvaal克拉通的其他部分之间的历史。总体而言，该项目有助于了解太古代早期地壳演化，并设想与处理南部非洲问题的其他SPP1833项目密切合作。

This project will investigate the oldest crustal components in two poorly known areas of the Zimbabwe and eastern Kaapvaal cratons, using field investigations, single zircon dating, geochemistry, as well as Hf and Nd isotopic systems. In central Zimbabwe, our preliminary work has identified several granitoid gneisses with zircon ages >3.6 Ga, and our aim is to understand the igneous, structural and metamorphic history of the terranes in which these rocks occur. In the eastern Kaapvaal craton, within a gneiss terrane of central Swaziland, we shall investigate an Archaean sequence of granulite-facies supracrustal rocks containing detrital zircons >3.6 Ga as well as the surrounding granitoid gneisses in which we also expect very ancient crustal components, The aim is to identify the source area of the ancient zircons and to understand the history of this ancient terrane in relation to the Ancient Gneiss Complex of Swaziland and the neighbouring Barberton Greenstone Belt and other parts of the Kaapvaal craton. Overall, this project is a contribution to understand early Archaean crustal evolution, and close cooperation with other SPP1833 projects dealing with southern Africa is envisaged.