2 November 2017

Weathering in komatiite

Posted by Callan Bentley

This morning on Twitter I was reminded of komatiites, those “extinct” ultramafic lavas that were relatively common eruptions during the Archean. I’ve actually got a good number of komatiite photos to share from my time last year in South Africa’s Barberton Greenstone Belt.

But since time is short this morning, I’ll start with a short photo set of three images, all showing different aspects of how these ultramafic rocks weather in the relatively dry climate of the South African mountains:

Students: what weathering patterns do you notice in these images? I’ll come back to this post later and tell you what I see, but first, let’s hear your observations and interpretations.