Cratonwide Overlap Assemblage Shamvaian Group

The shamvaian Group consists of a sequence of coarse clastic rocks that overlie the upper Greenstones in several locations. These conglomerates, arkoses, and graywackes are well known from the Harare, Midlands, Masvingo, and Belingwe greenstone belts. The Cheshire Formation, the top unit of the Belingwe greenstone belt, consists of a heterogeneous succession of sedimentary rocks including conglomerate, sandstone, siltstone, argillite, limestone, cherty limestone, stromatolitic limestone, and minor banded iron formation. The shamvaian Group is intruded by the circa 2.6 billion-year-old Chilimanzi suite granites, providing an upper age limit on deposition. In the Bindura-Shamva greenstone belt the Shamvaian Group is 1.2 miles (2 km) thick, beginning with basal conglomerates and grading up into a thick sandstone sequence. Tonalitic clasts in the basal conglomerate have yielded igneous ages of 3.2, 2.9, 2.8, and 2.68 billion years. Felsic volcanics associated with the Shamvaian Group in several greenstone belts have ages of 2.66 to 2.64 billion years.

Was this article helpful?

0 0
How To Survive The End Of The World

How To Survive The End Of The World

Preparing for Armageddon, Natural Disasters, Nuclear Strikes, the Zombie Apocalypse, and Every Other Threat to Human Life on Earth. Most of us have thought about how we would handle various types of scenarios that could signal the end of the world. There are plenty of movies on the subject, psychological papers, and even survivalists that are part of reality TV shows. Perhaps you have had dreams about being one of the few left and what you would do in order to survive.

Get My Free Ebook

Post a comment