From the album, GAIA
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The Isua Greenstone Belt is an Archean greenstone belt in southwestern Greenland. The belt is aged between 3.7 and 3.8 Ga, making it among the oldest rock in the world. The belt contains variably metamorphosed mafic volcanic and sedimentary rocks. The occurrence of Boninitic geochemical signatures offers evidence that plate tectonic processes may be responsible for the creation of the belt. Pillowed basalts indicate that liquid water existed on the surface at this time.