2020-6-1 · In the 3.55–3.22 Ga Barberton Greenstone Belt (BGB), South Africa, the ~3.445 Ga felsic volcanic unit at the top of the Hooggenoeg Formation (), termed member H6 by Lowe and Byerly (1999), is composed of up to 1000 m of felsic volcanic rock, including a large hypabyssal intrusive body and flanking aprons of volcaniclastic debris (Lowe et al., 2012) interpreted to represent a range of shallow ...