Wednesday, 10 March 2021

4.6 b yo meteorite found in Algeria

A 4.6 billion-year-old meteorite may be the oldest rock ever analyzed. The rock, named Erg Chech 002, was discovered in May 2020 in the Erg Chech area of southwestern Algeria. Unlike most discovered meteorites, which are made of basalt, created after lava has cooled, the meteorite is composed of a much rarer volcanic rock called andesite. Achrondites are igneous rocks that come from a body that has undergone internal melting that distinguishes the core from its crust. Silica-infused andesite crusts were likely common during our solar system’s protoplanet-forming stage.
Stones found in May 2020 totalling 22.8 kg were found showing distinctive large greenish orthopyroxene megacrysts.