Geochemical and Sr-Nd isotopic records of Paleoproterozoic metavolcanics and mafic intrusive rocks from the West African Craton: Evidence for petrogenesis and tectonic setting
| Autor: | Prosper M. Nude, Daniel Kwayisi, Frank K. Nyame, Ben-Can Su, Patrick Asamoah Sakyi, Daniel K. Asiedu, Solomon Anum, Ben-Xun Su |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
geography
geography.geographical_feature_category 010504 meteorology & atmospheric sciences Continental crust Archean Geochemistry Geology 010502 geochemistry & geophysics 01 natural sciences Craton Birimian Island arc Mafic Petrology 0105 earth and related environmental sciences Petrogenesis Terrane |
| Zdroj: | Geological Journal. 53:725-741 |
| ISSN: | 0072-1050 |
| DOI: | 10.1002/gj.2923 |
| Popis: | Metavolcanics and mafic intrusive rocks of the Paleoproterozoic Birimian terrane in the southeastern part of the West African Craton, Ghana, were analyzed for major and trace elements and Nd and Sr isotopic data to constrain the geodynamic evolution of the Birimian Supergroup. The metavolcanic rocks consist of metabasalts, meta-andesites, and amphibolites, whereas the mafic intrusions are mainly gabbros, hornblendites, and dolerites. The rocks are tholeiitic in composition and show the classic features of arc magmatism. The metavolcanics display significant enrichments in large ion lithophile elements (LILE) and light rare earth elements, relative to high field strength elements (HFSE) and heavy rare earth elements. The multielement patterns of the rocks also show positive Pb, Ba, Th, and Sr and negative Nb, Ta, and Ce anomalies that are typical characteristics of subduction-related magmas. They also have La/Nb ratios |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text