 The land on which Colton Point State Park sits was once part of the coastline of a shallow sea that covered a great portion of what is now North America . The high mountains to the east of the sea gradually eroded , causing a buildup of sediment made up primarily of clay , sand and gravel . Tremendous pressure on the sediment caused the formation of the rocks that are found today in the Pine Creek drainage basin : sandstone , shale , conglomerates , limestone , and coal . 
