Publications

No abstract available.

Whirling disease is a parasitic infection of trout and salmon by the myxosporean protozoan Myxobolus cerebralis (Syn. Myxosoma cerebralis). This parasite has selective tropism for cartilage; infection can cause deformities of the axial skeleton and neural damage that results in 'blacktail.' The disease is named for the erratic, tail-chasing, 'whirling' in young fish that are startled or fed. Heavy

No abstract available

No abstract available.

This [summary of] U.S. Geological Survey Open-File Report 92-585 contains a listing of publications authored or co-authored by members of the Branch of Atlantic Marine Geology during 1991. Results of Branch investigations are distributed in a variety of ways, including maps, journal articles, abstracts and U.S.G.S. publications. Copies of U.S.G.S. Open File Reports may generally be obtained from

Water levels were measured in 51 observation wells in the vicinity of the Elkhart Water Works Main Street well field during 5 days of normal pumping at the well field and little or no recharge to the ground water from precipitation. Water levels were measured once each day during December 18-22, 1989. Water-level altitudes were plotted and contoured on maps to determine the distribution of ground-

No abstract available.

No abstract available.

The Knoxville 1° x 2° quadrangle spans the Southern Blue Ridge physiographic province at its widest point from eastern Tennessee across western North Carolina to the northwest corner of South Carolina. The quadrangle also contains small parts of the Valley and Ridge province in Tennessee and the Piedmont province in North and South Carolina. Bedrock in the Valley and Ridge consists of unmetamorpho

More accurate alternatives to the widely used harmonic mean interblock transmissivity are proposed for block-centered finite-difference models of ground-water flow in unconfined aquifers and in aquifers having smoothly varying transmissivity. The harmonic mean is the exact interblock transmissivity for steady-state one-dimensional flow with no recharge if the transmissivity is assumed to be spatia

Documentation of the 1988 drought in Indiana was undertaken to aid water-management agencies and planners concerned with periods of below-normal precipitation and their effect on commercial, agricultural, and residential water use. Precipitation, temperature, Palmer Drought Severity Indices, and ground- and surface-water levels from water years 1988 and 1989 were compared to the historical record

A total of 304 nutrient samples were collected from May 1990 through September 1991 to determine concentrations and loads of nutrients in water discharged from two spring basins in Cumberland County, Pa. Fifty-four percent of these nutrient samples were for the evaluation of (1) laboratory consistency, (2) container and preservative cleanliness, (3) maintenance of analyte representativeness as aff