Proterozoic Land Masses
During the Proterozoic Eon, while the oxygen was rusting iron, mountains were beginning to build. Mountains build due to two or more plate tectonics merging together. When these plates converged, molten granite melted the igneous rock around the outer edges of what used to be micro-continents. The mountain building during the Proterozoic era expanded Northern America.
Many geologists believe the Proterozoic Earth was covered in glaciers for several million years. Others believe the glaciations happened at least twice during the Proterozoic, once in the beginning and once in the end. Until the Earth warmed up due to carbon dioxide being released from volcanoes, life on the planet would have to stay around the hydrothermal vents of the ocean. The final Ice Age of the Proterozoic marked the end of this eon and the beginning of the Cambrian Era.
Many geologists believe the Proterozoic Earth was covered in glaciers for several million years. Others believe the glaciations happened at least twice during the Proterozoic, once in the beginning and once in the end. Until the Earth warmed up due to carbon dioxide being released from volcanoes, life on the planet would have to stay around the hydrothermal vents of the ocean. The final Ice Age of the Proterozoic marked the end of this eon and the beginning of the Cambrian Era.