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Research about Virginia

Source-linked reports with geographic coverage including Virginia.

At least 577 records · Page 32Linked to original sources
USGS1972

U.S. Geological Survey National Center, Reston, Virginia

In 1917 the Geological Survey moved into the newly built Interior Building near the White House in Washington, D. C. Twenty years later a larger building was constructed nearby to house the expanding U. S. Department of the Interior. Height restrictions reduced the planned size of the new building, and the Geological Survey was compelled to remain in the older Interior Building now identified as the General Services Administration Building. Expansion of the Survey's programs, and particularly the overall government need for additional office space in downtown Washington, has resulted in the Survey's activities being presently housed in 30 different buildings, at 17 widely scattered locations throughout the Washington Metropolitan Area.

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USGS1971

Correlation of uranium, thorium, and potassium with aeroradioaetivity in the Berea Area, Virginia

In the Berea area, a small quartz monzonite pluton intrudes chlorite-actinolite schist and is overlapped by Coastal Plain sand and gravel deposits. A detailed aeroradioactivity survey of the area shows unusually high radioactivity (1,150 counts per second) over the quartz monzonite. A total of 22 auger samples was taken across all formations to a depth of 2 to 3 feet, and radioelement concentrations were determined by gamma-ray spectrometry. There is a general direct correlation of high radioactivity with increase in radioelement concentrations. Abundances of uranium and particularly thorium in the quartz monzonite are two and three times the average for rocks of this type; a comparison is made with other granitic rocks high in uranium and thorium. © 1971 Society of Economic Geologists, Inc.

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USGS1970

Correlation of aeromagnetics and aeroradioactivity with lithology in the Spotsylvania area, Virginia

The U.S. Geological Survey made a detailed aeromagnetic and aeroradioactivity survey of 1050 sq mi of the Spotsylvania area in the Piedmont province of eastern Virginia. The study area consists of sixteen 7 1/2-minute quadrangles in Spotsylvania and adjoining counties, Virginia. East-west traverses were flown at a spacing of 1/2 mi and a flight elevation of 500 ft above ground. Geophysical data were compiled at a scale of 1:24,000, with a contour interval of 25 gammas for the magnetics and 25 counts per sec for the aeroradioactivity. The geophysical data were checked in the field, and a lithologic map was made. Correlation is excellent between geophysical data and lithologic units, and it is evident that good detailed aeromagnetic and aeroradioactivity maps can provide appreciable shortcuts in mapping an area such as the Piedmont, where lithologies are complex and outcrops sparse. Radioactivity highs are generally associated with magnetic lows, and more importantly, for purposes of geologic interpretation where the magnetic expression is flat and featureless, there is considerable radioactivity detail for geologic guidance. By using the two geophysical maps in conjunction, the geology between widely spaced outcrops can be worked out. In the study area, high radioactivity and low magnetic intensity characterize granitic rocks, many of which were not previously mapped. Mafic bodies are characterized by high magnetic values and low radioactivity. Much of the area is underlain by a sequence of metamorphosed sedimentary and volcanic rocks having alternating quartz-muscovite and magnetiferous chlorite-actinolite assemblages. © 1970, The Geological Society of America, Inc.

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USGS1970

Flood of August 1969 in Virginia

Hurricane Camille became a tropical depression and soaked central Virginia with up to 28 inches of rain during the night of August 19th and morning of the 20th. The rains, flash floods, and rain-induced landslides accompanying the storm's passage have been called the worst natural disaster ever to strike Virginia. Discharge of streams in the James, Potomac, Rappahapnock, and York River basins exceeded previous known maximums. At Tye River near Lovingston the peak flood discharge was eight times the previous high during the 31 years of record. James River stations downstream from the Maury River recorded peak flows of greater than 100-year recurrence interval. As of Nov. 13, 1969, the State had counted 113 dead and 102 injured with 39 persons still missing. The total damage amounted to over $116 million. This report provides hydrologic data needed for planning and design. The report includes a general description of the flood; precipitation information; sediment aspects of the flood; and records of stage and/or discharge for 105 sites.

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USGS1969

Ancient lavas in Shenandoah National Park near Luray, Virginia

In the Blue Ridge Province of northern Virginia, Maryland, and southern Pennsylvania, Lower Cambrian beds are underlain by a thick sequence of greenstone and interbedded sedimentary rocks known as the Catoctin Formation. An area near Luray, Va., was studied to determine the thickness of the formation, its relationship to overlying and underlying rocks, and the original nature of the lavas from which the Catoctin greenstone was derived. There the Catoctin Formation lies unconformably on granitic rocks. Its basal sedimentary layer ranges from a few inches to 150 feet in thickness and contains pebbles of underlying basement rocks. The erosion surface beneath the Catoctin is irregular, and in several places, hills as much as 1,000 feet high were buried beneath the Catoctin lavas. No important time break is indicated between the deposition of the Catoctin Formation and the overlying Cambrian sediments. The original Catoctin lavas were basaltic and were probably normal plateau basalts. Columnar joints, amygdules, sedimentary dikes, flow breccias low-dipping primary joints, and other primary structures are well preserved.

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USGS1964

A merganser die-off associated with larval eustrongylides

A die-off of red-breasted mergansers on Lake Holly, Virginia Beach, Virginia, was found to be due to a larval Eustrongylides. Massive tissue destruction and hemorrhage was produced by the migration of the larval Eustrongylides. Earlier stages of the same Eustrongylides were found in eastern mosquitofish and silversides upon which the mergansers had been feeding. In addition, residues of DDT were found in mosquitofish, gizzard shad, and five mergansers collected from Lake Holly, and in the tissues of two mergansers from Back Bay, Virginia. However, the information available was insufficient to establish the significance of these residue levels.

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