Geology, geomorphology, soils
Briefly describe the main land formations and characteristics.
The bedrock consists of sedimentary Paleozoic rocks of the Silurian and Devonian eras, lying flat but sloping gently in a southern direction at depths of from 80-115 m. It is overlain by the Norfolk sandplains which are thought to have been deposited in the shallow stages of glacial Lake Whittlesey, some 13,000 years ago. They have been moulded by the post-glacial retreat of ice and associated drainage, and eroded further by wind action which has created small sand hills in the mainland area.
The Long Point formation may have started to form some 7,600 years ago at the location of a cross-lake glacial moraine; it has been reworked considerably again from some 4,000 years ago when the present configuration of Lake Erie emerged. The source of the materials that are deposited at Long Point are the clay/sand bluffs of the Lake Erie shore extending up to 95 km west of the point. Erosion is particularly active at times of high water levels in Lake Erie combined with intense seasonal storms. The sediment is carried by longshore currents eastwards and deposited at Long Point. Deposition has been enhanced by the low underwater moraine ridge. The sediments are deposited in a series of "sand waves" which, over a period of years, move east along the lakeshore side of the point to the tip where they are deposited and help replenish materials lost through wave and wind erosion. The Big Creek watershed (730 km2) is the main one draining into the Inner Bay at Long Point.
The sandplains grade into several small silt and clay plains near Lake Erie. Plain field sand and grey brown luvisols typify normal and somewhat wetter sites. Gleysols and organic matter occur at sites where drainage is restricted.
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