sentences:  The first period was a lengthy period of geologic instability from the origin of the planet until roughly 1,100 million years ago.During this time, the state's Precambrian bedrock was formed by volcanism and the deposition of sedimentary rock and then modified by processes such as faulting, folding and erosion.In the second period, many layers of sedimentary rock were formed by deposition and lithification of successive layers of sediment from runoff and repeated incursions of the sea.