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Wayne A. Pettyjohn

Publications and source records attributed to Wayne A. Pettyjohn.

4 recordsLinked to original sources
USGS2010

Geohydrologic use of lithofacies maps in glaciated areas

Subsurface conditions may differ considerably from conditions indicated by surficial geologic maps, particularly in glaciated areas. Therefore, it is advantageous to use a series of lithofacies maps as a sequence of overlays plotted on transparent paper. Such maps permit direct visual determination of the lithology and areal extent of aquifers and indicate areas of possible stream losses or gains. They indicate areas and boundaries of confining layers and, in some places, they may be used to delineate areas of water-table and artesian conditions. They are especially useful in determining buried channels in glaciated areas. The porosity of rock units making up an aquifer may be plotted on a lithofacies map, and the product of the volume of each lithologic type and the porosity provides an estimate of the total water in storage. In addition, if the water-bearing properties are known, the quantity of water moving through an aquifer and the amount available to wells may be determined. Lithofacies maps also aid in the explanation of complex changes in water quality.

Water Resources Research↗
USGS2006

Design and construction of a dual recharge system at Minot, North Dakota

In 1965, a ground-water recharge facility was constructed and placed in operation to forestall an impending water shortage at Minot, North Dakota. The facility is unique in that the rate of recharge to a buried sand and gravel aquifer is augmented by perforating an overlying bed of clay using hydraulic connectors (gravel-filled bored holes) in conjunction with an open-pit excavation. The connectors were drilled by typical well-boring techniques and the open pit was excavated by common construction methods. The recharge technique made it possible to add about million gallons per day of water to underground storage with a total capital investment of about $200,000. The alternative originally proposed was a 50-mile long pipeline to Garrison Reservoir, at a 1959 estimated cost of $12,000,000. The recharge technique employed at Minot should have wide application in the ground-water industry in areas where natural recharge to permeable deposits is impeded by overlying beds of low permeability.

North Dakota↗
USGS1967

Geohydrology of the Souris River Valley in the vicinity of Minot, North Dakota

The Minot area is in the north-central part of North Dakota and includes part of the Souris River valley. The region is covered by glacial drift of late Wisconsin age except in small areas where the Fort Union Formation of Tertiary age crops out. Thickness of the drift is controlled by the topography of the bedrock. In places the drift is more than 450 feet thick, but it averages about 100 feet thick. Water from the Fort Union Formation is soft and is of sodium bicarbonate type that is undesirable for many uses. Wells in the formation produce only a few gallons per minute. Six glacial aquifers were studied in the report area, but detailed work was limited to the Minot aquifer. The Sundre buried-channel and the lower Souris aquifers contain large quantities of bard water of good chemical quality, but little is known of their hydraulic characteristics owing to lack of development. The North Hill and South Hill aquifers generally provide small quantities of hard water that may be high in iron and sodium. The northwest buried-channel aquifer has a high content of iron and chloride. Locally as much as 1,000 gallons per minute may be pumped from it. The Minot aquifer is a thick deposit of sand and gravel confined to the Souris River valley. The water level has declined more than 70 feet since the first municipal well began pumping in 1916. In .some places the water level in the aquifer declined more than 20 feet during 1961-1963. The rapid decline in water level indicates that a serious water shortage may arise in the near future unless counter measures are taken to prevent it. The Minot aquifer is under both artesian and water-table conditions. In places the transmissibility exceeds 250,000 gallons per day per foot. In 1963, 13 municipal wells pump'ed an average of nearly 4 million gallons per day from the aquifer. Some wells produce as much as 1,000 gallons per minute. The Minot aquifer receives most of its recharge from the buried glaciofiuvial deposits and from the Souris River. Natural recharge probably average about 3 million gallons per day. About 56,000 acre-feet of water available to wells was in storage in 1963. Artificial recharge could be used to counteract the rapid decline in water levels. Several feasible artificial recharge sites are in the western part of Minot, where highly permeable sand and gravel crop out.

North Dakota↗