I-1 - Ice-Contact Stratified Deposits:!UND;  Sand and gravel deposited by glacial meltwater streams, with some resedimentation by gravity
processes.  This unit occurs as eskers and irregular-shaped hummocks.  Aggregate deposits of this type are variable in thickness,
but generally of limited lateral extent, with a variable thickness of overburden.  Percentage gravel is variable, but locally may
be quite high, while in some areas the deposits may be entirely sand.  Data on percent deleterious material is lacking, however
the quality of these deposits is probably similar to type O deposits.

I-2 - Ice-contact Stratified Deposits:!UND;  Sand and gravel deposited by glacial meltwater streams in contact with glacial ice, with some
resedimentation by gravity flow processes.  Aggregate deposits of this type are variable in thickness, and lateral extent.  This
type of deposit was subsequently buried by later glacial advances and therefore has a variable, but generally pervasive thickness
of overburden.  Percentage of gravel is variable, but locally may be quite high, while in some areas the deposits may be entirely
sand.  Percent deleterious materialis quite variable, but is generally high relative to other aggregate deposits in the county.

O-1 - Outwash:!UND;   Sand and gravel deposited by glacial meltwater streams confined to a valley.  Aggregate deposits in this unit are
moderately thick and have generally thin overburden.  Gravel percentage is fairly high, with a mixture of coarse and fine
gravel.  Percentage of deleterious material, chiefly shale, but including iron oxides, is moderately high relative to other
1deposits in the region.  This unit represents part of the outwash valley train in the Hawley area where gravel mining has
occurred and subsurface data indicate potential for further development.

O-2 - Outwash:!UND;  Chiefly sand deposited by glacial meltwater streams confined to a valley.  This unit occurs in the glacial drainage
channels east and south of Hawley.  The aggregate potential of this unit will be limited by low percentages of gravel.  Gravel-rich
zones may occur beneath sand overburden.  The percentage of deleterious material in this type of deposit is probably similar to
other type O deposits, in other words, moderate amounts of shale.

O-3 and O-4 - Collapsed Outwash:!UND;  Sand and gravel deposited by glacial meltwater streams flowing upon stagnant ice.  These two units form
a collapsed outwash plain in the southeastern part of the county.  Aggregate deposits have variable thickness, but are locally
quite thick.  Overburden thickness is also variable, but is generally minimal.  Percent gravel is variable, but is locally quite
high, with some areas containing appreciable quantities of coarse gravel.  Percentage of deleterious material, chiefly shale,
is moderately high relative to other deposits in the region.  Unit O-3 is differentiated from unit O-4 by a higher density
of gravel pits and by subsurface data indicating potential for further development.  Aggregate deposits that may occur in unit
O-4 will be very simillar to O-3 deposits, but the probability of finding a deposit in these areas is inferred to be lower.

So - Subaqueous Outwash of Northeastern Provenance:!UND;  Sand and gravel deposited by subglacial meltwater streams where they entered
a lake that existed in the Red River Valley prior to Lake Agassiz.  These deposits are not expressed as depositional landforms,
but are exposed at the surface where the younger sediment has been removed by either stream erosion, or by wave action in Lake
Agassiz.  Aggregate deposits of this type are locally very thick (75 to 100 feet), but may be moderately thick, or absent in
places.  Overburden thickness is highly variable, ranging from minimal to excessive (greater than 40 feet).  Gravel percentage
is also highly variable, ranging from high percentage of coarse gravel to entirely sand.  Percentage of deleterious material
(shale and iron oxides) is generally low, characteristic of northeastern-source deposits.  Potential for these types of deposits
is inferred to be somewhat higher in proximity to erosional landforms present within this unit.  This type of deposit represents
the highest quality aggregate resource present in the entire region.

B-1 - Major Beach Ridges:!UND;   Sand and gravel deposited in near-shore environments of Lake Agassiz.  Forms prominent beach ridges.
Aggregate deposits are typically thin (10 to 20 feet thick) and narrow, but generally have very little overburden.  Gravel
percentage is variable, and is generally dominated by fine gravel (#10 mesh to #4 mesh).  Percentage of deleterious material
is generally low.

B-2 - Minor Beach Ridges:!UND;  Sand and gravel deposited in near-shore environments of Lake Agassiz.  This unit represents minor beach
ridges, and in some cases, offshore bars composed entirely of sand.  Examples of this type of deposit are not common, therefore
supporting data are not abundant.  Aggregate deposits are inferred to be rather thin, but generally with little overburden.
Low percentages of gravel will limit these deposits to certain uses.  Percentage of deleterious material is inferred to be low.

B-e - Beach Deposits Not in Ridges:!UND;  Chiefly sand, with local concentrations of sand and gravel, deposited in near-shore environments
of Lake Agassiz.  This unit consists of that portion of the shoreline area of Lake Agassiz which is outside the other mapping
units (beach ridges, for example).  These deposits are generally thin.  Deposits within this unit generally have little overburden.
Percentage of gravel is quite variable, but is generally low to intermediate.  The gravel fraction may be predominantly fine
gravel.  Percentage of deleterious material is generally low, as in other beach deposits.  Occurring within this unit in the
vicinity of Muskoda are meltwater stream deposits similar to type O-1 which are buried by till and beach-deposited sand and gravel.
This unit has potential for other types of buried deposits, especially in the vicinity of shoreline erosional features.
