Symbol	Surface Geology Description
	Post Glacial
	alluvium and marsh deposits:  stratified sand and gravel in present stream valleys, and peat, mucky silt, or sand in areas where the water table is at or slightly above the surface for part of the year
	Glacial
	outwash:  stratified sand and gravel deposits by glacial melt waters as a broad-flood plain
	outwash and till:  low hills flat-topped terraces, and deltas of stratified silt, sand, and gravels includes deposits of washed till
	moraine deposits:  ridges of very uneven topography composed predominantly of sandy till and some ice-contact deposits of stratified sand and gravel
	ground moraine deposits:  till and minor amounts of stratified silt, sand, and gravel; forms a relatively thick mantle over bedrock
	Preglacial
	sandstone:  white to light-gray, fine to coarse grained sandstone; some beds are well indurated; ripple marks and cross bedding are common
	crystalline rock:  consists largely of granite; however, gneiss, schist, shale, and quartzite are exposed at the surface in the crystalline rock area

(Source:  Holt, C. L. R., Jr., 4).  

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