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M.G. Croft

Publications and source records attributed to M.G. Croft.

5 recordsLinked to original sources
USGS1987

Hydrology of area 46, Northern Great Plains and Rocky Mountain coal provinces, North Dakota

This report is one of a series that describes the hydrology of coal provinces nationwide. The Northern Great Plains and Rocky Mountain Coal Provinces are divided into 20 separate reporting areas which are numbered 43 to 62. This report provides general hydrologic information for Area 46 using a brief text with accompanying maps, charts, or graphs. This information may be used to describe the hydrology of the general area of any existing or proposed mine. Some of the more obvious hydrologic problems of coal development that will need to be addressed before development are disruption of aquifers and potential contamination of streams, aquifers, and the atmosphere. Area 46 is in northwestern North Dakota and is composed of parts or all of 14 hydrologic units based on surface-water drainage basins. The area is drained by the Missouri and Souris Rivers. Lignite-bearing rocks of late Paleocene age underlie nearly all of Area 46. The thickest and most continuous lignite beds occur in the Sentinel Butte and Tongue River Members of the Fort Union Formation. Alluvial deposits and a veneer of glacial drift of late Pleistocene age overlie the lignite-bearing rocks. The climate of the area is semiarid. Mean annual precipitation ranges from 13.9 to 17.8 inches. Mean annual temperatures range from 37.7°F at Bowbells to 40.9°F at Williston. Mean monthly temperatures at Williston range from 8.3°F to 70°F. The growing season is about 125 days. A fairly comprehensive data base for streamflow and water quality in streams is available for Area 46. Many of the small-stream monitoring sites have been operated during the last few years to provide a data base before coal development. With the exception of the Missouri River, which is controlled by several dams, both the quantity and quality of water varies greatly in all streams. A ground-water observation network for water levels and water quality has been established through county ground-water resource investigations and other ground-water studies and provides an adequate data base. Three activities within the U.S. Geological Survey identify and provide access to hydrologic data. These are the National Water-Data Exchange (NAWDEX), the National Water-Data Storage and Retrieval System (WATSTORE), and the Office of Water-Data Coordination (OWDC).

Open-File Report↗
USGS1974

Water supply at Painted Canyon Overlook, Theodore Roosevelt National Memorial Park (South Unit), southwestern North Dakota

A 1,930-foot (588-metre) water-supply well was constructed at the Painted Canyon Overlook, Theodore Roosevelt National Memorial Park (South Unit), southwestern North Dakota. Aquifers underlying the site are in rocks of Late Cretaceous and Tertiary age. These rocks have an aggreqate thickness of about 2,000 feet (610 metres). The well screen is set in the Fox Hills Sandstone of Late Cretaceous age. The formation consists of about 200 feet (61 metres) of interbedded marine sandstone, siltstone, and claystone. The sandstone is very fine to fine grained. The well was pumped for 24 hours w·ith a submersible pump at rates from 72 to 77 gallons per minu t e (4.5 to 4.9 litres per second) and had a specific capacity of about 0.4 gallon per minute per foot (0.08 litre per second per metre). The water was a sodium bicarbonate type and contained 1,050 milligrams per litre dissolved solids.

Open-File Report↗
USGS1972

Subsurface geology of the late Tertiary and Quaternary water-bearing deposits of the southern part of the San Joaquin Valley, California

The study area, which includes about 5,000 square miles of the southern part of the San Joaquin Valley, is a broad structural trough of mostly interior drainage. The Sierra Nevada on the east is composed of consolidated igneous and metamorphic rocks of pre-Tertiary age. The surface of these rocks slopes 4?-6? southwestward from the foothills and underlies the valley. The Coast Ranges on the west consist mostly of complexly folded and faulted consolidated marine and nonmarine sedimentary rocks of Jurassic, Cretaceous, and Tertiary age, which dip eastward and overlie the basement complex. Unconsolidated deposits, of late Pliocene to Holocene age, blanket the underlying consolidated rocks in the valley and are the source of most of the fresh ground water. The unconsolidated deposits, the subject of this report, are divided into informal stratigraphic units on the basis of source of sediment, environment of deposition, and texture. Flood-basin, lacustrine, and marsh deposits are fine grained and underlie the valley trough. They range in age from late Pliocene to Holocene. These deposits, consisting of nearly impermeable gypsiferous fine sand, silt, and clay, are more than 3,000 feet thick beneath parts of Tulare Lake bed. In other parts of the trough, flood-basin, lacustrine, and marsh deposits branch into clayey or silty clay tongues designated by the letter symbols A to F. Three of these tongues, the E, C, and A clays, lie beneath large areas of the southern part of the valley. The E clay includes the Corcoran Clay Member of the Tulare Formation, the most extensive hydrologic confining layer in the valley. The E clay underlies about 3,500 square miles of bottom land and western slopes. The beds generally are dark-greenish-gray mostly diatomaceous silty clay of Pleistocene age. Marginally, the unit bifurcates into an upper and a lower stratum that contains thin beds of moderately yellowish-brown silt and sand. The E clay is warped into broad, gentle northwesterly trending anticlines and synclines. The C clay, of Pleistocene age, is a fine-grained lacustrine or paludal deposit occurring 220-300 feet beneath Tulare Lake bed and parts of Fresno Slough. The beds consist of bluish-gray silty clay. Structural contours indicate that the C clay has been extensively warped and folded. The A clay of Pleistocene and Holocene (?) age is a fine-grained lacustrine or paludal deposit occurring 10-60 feet beneath Buena Vista, Kern, and Tulare Lake beds, and parts of Fresno Slough. The clay is mainly blue or dark greenish gray, plastic, and highly organic. In some areas the unit is separated into an upper and a lower stratum by several feet of sand. A radiocarbon date of 26,780 ? 600 years was obtained from wood cored 3 feet beneath the clay. Continental deposits are arkosic beds of late Pliocene and Pleistocene (?) age and were derived from the Sierra Nevada, Tehachapi, and San Emigdio Mountains. In places, a reduced-oxidized contact transgresses the deposits derived from the Sierra Nevada. The reduced deposits consist of moderately permeable bluish-green or bluish-gray fine to medium sand, silt, and clay. The oxidized deposits consist mainly of poorly permeable yellowish-brown silt and fine sand. Deposits derived from the Tehachapi and the San Emigdio Mountains consist of poorly to moderately permeable yellowish-brown sand and silt. Continental and alluvial deposits of Tertiary and Quaternary age that were derived from the Coast Ranges consist mainly of poorly to moderately permeable yellowish-brown gravel, sand, silt, and clay. They include the Tulare Formation and overlying alluvial deposits. Alluvium is composed of coarse arkosic deposits derived from the Sierra Nevada, Tehachapi, and San Emigdio Mountains. A reduced-oxidized contact also transgresses the alluvial deposits derived from the Sierra Nevada. The oxidized deposits consist of poorly to highly permeable yellowish-brown gravel, sand, silt, and clay. The reduc

Water Supply Paper↗