Fig. 1

Summary geological map of the Isua area, Nuuk region, West Greenland. The arcuate Isua supracrustal belt is composed of two temporally distinct terranes, both containing a range of volcanic and metasedimentary rocks. The northern terrane has rocks with ages of ca. 3,700 million years old and the southern terrane with rock ages of ca. 3,800 million years old (constrained by >30 zircon U/Pb age determinations – see Nutman and Friend 2009). The legend lists the rock types present in each terrane