Granitoid-greenstone relationships in the eastern Kaapvaal craton and implications for early crustal evolution

卡普瓦尔克拉通东部花岗岩-绿岩关系及其对早期地壳演化的影响

• 批准号: 213660822
• 负责人: Privatdozent Dr. Jörg Elis Hoffmann
• 金额: --
• 依托单位: Institut für Geowissenschaften
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/213660822?language=en
• 关键词: Granitoid; greenstone; relationships; eastern; Kaapvaal

Following up on our project, where the early Archaean continental crustal histories of the Ancient Gneiss Complex (AGC),of Swaziland and the Itsaq Gneiss Complex (IGC) of southern West Greenland) have been studied, we now focus on the geochemistry of mafic and ultramafic rocks of the lowermost stratigraphic units of the Barberton Greenstone Belt, the ca. 3.53 Ga Theespruit and Sandspruit Formations, South Africa, as well as on greenstone inliers in the Ancient Gneiss Complex of Swaziland. The preliminary results of our first project phase hint at a felsic basement to the above greenstone sequences and older continental crust as now exposed in the AGC. Chemical signatures of mafic-ultramafic volcanic rocks possible crustal contamination may be traced using a combination of major and trace elements and Hafnium-Neodymium isotope compositions. Moreover, we plan to carry out 142Nd analyses on different rock types (gneisses, amphibolites) of the Ancient Gneiss Complex and the lithologies of the Barberton Greenstone Belt to investigate whether the oldest rocks of the Kaapvaal craton had an early differentiation history that possibly began in the Hadean, when the extinct nuclide system was still active. We shall investigate whether a possible 142Nd anomaly may have been diminished by juvenile crustal contributions with time or whether it sustained in younger magmatic rocks.

跟进我们的项目，在这里，已经研究了Swaziland的古老片麻岩建筑群（AGC），斯威士兰和西部西部格陵兰南部西部西部格陵兰岛的伊萨克碎石综合体（IGC）的早期大陆甲壳历史。 3.53 Ga Theespruit和Sandspruit地层，南非以及斯威士兰古代片麻岩综合体的绿岩嵌入式。我们的第一个项目阶段的初步结果暗示了Felsic地下室对上述绿岩序列和较旧的大陆壳，如目前在AGC中所暴露的。可以使用主要元素和痕量元素和Hafnium-Neodymium同位素组成的组合来追溯镁铁质粉状火山岩的化学特征。此外，我们计划对古代片麻岩建筑群的不同岩石类型（片麻岩，闪石）进行第142次分析，以及Barberton Greenstone腰带的岩性，以研究Kaapvaal Craton最古老的岩石早期差异历史是否具有早期的差异历史，当时在Hadean中可能始于Hadean，当时已经存在了固定的Nuclide System。我们将调查是否有可能因时间而被少年地壳贡献减少142个异常，或者是否在年轻的岩浆岩石中持续下去。

项目成果

Archaean Crystalline Rocks of the Eastern Kaapvaal Craton

• DOI: 10.1007/978-3-319-78652-0_1
• 发表时间: 2019
• 期刊: Regional Geology Reviews
• 作者: A. Kröner;J. Hoffmann;J. Wong;H. Geng;K. Schneider;H. Xie;Jin-Hui Yang;N. Nhleko

Generation of early Archaean grey gneisses through melting of older crust in the eastern Kaapvaal craton, southern Africa

• DOI: 10.1016/j.precamres.2014.07.017
• 发表时间: 2014-12-01
• 期刊: PRECAMBRIAN RESEARCH
• 影响因子: 3.8
• 作者: Kroener, Alfred;Hoffmann, J. Elis;Yang, Jinhui
• 通讯作者: Yang, Jinhui

Coexistence of enriched and modern-like 142 Nd signatures in Archean igneous rocks of the eastern Kaapvaal Craton, southern Africa

南非卡普瓦尔克拉通东部太古代火成岩中丰富且现代的 142 Nd 特征共存

• DOI: 10.1016/j.epsl.2018.01.022
• 发表时间: 2018
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: Schneider;Hoffmann;Münker;Kröner
• 通讯作者: Kröner

Constraining the process of Eoarchean TTG formation in the Itsaq Gneiss Complex, southern West Greenland

• DOI: 10.1016/j.epsl.2013.11.050
• 发表时间: 2014-02-15
• 期刊: EARTH AND PLANETARY SCIENCE LETTERS
• 影响因子: 5.3
• 作者: Hoffmann, J. Elis;Nagel, Thorsten J.;Rosing, Minik T.
• 通讯作者: Rosing, Minik T.

The origin of highly radiogenic Hf isotope compositions in 3.33 Ga Commondale komatiite lavas (South Africa)

• DOI: 10.1016/j.chemgeo.2016.10.010
• 发表时间: 2017-04-20
• 期刊: CHEMICAL GEOLOGY
• 影响因子: 3.9
• 作者: Hoffmann, J. Elis;Wilson, Allan H.
• 通讯作者: Wilson, Allan H.