Uchi Subprovince (Paperback)

High Quality Content by WIKIPEDIA articles! The Uchi Subprovince is a Neoarchean volcanic sequence in Manitoba, Canada. It is the southern margin of the North Caribou terrane and comprises a number of greenstone belts, which contains volcanic rocks that record some 280 million years of volcanism. The Neoarchean is a geologic era within the Archaean. It spans the period of time from 2,800 to 2,500 million years ago-the period being defined chronometrically and not referenced to a specific level in a rock section on Earth. Oxygenic photosynthesis first evolved in this era and was accountable for the oxygen catastrophe which was to happen later in the paleoproterozoic from a poisonous buildup of oxygen in the atmosphere, produced by these oxygen producing photoautotrophs, which evolved earlier in the Neoarchean.