Geology topics

Research about Kentucky, Tennessee, Virginia

Source-linked reports with geographic coverage including Kentucky, Tennessee, Virginia.

4 recordsLinked to original sources

USGS2020

Modeling occupancy of rare stream fish species in the upper Cumberland and Kentucky River Basins

Biological conservation often requires an understanding of how environmental conditions affect species occurrence and detection probabilities. We used a hierarchical framework to evaluate these effects for several Appalachian stream fish species of conservation concern: Chrosomus cumberlandensis (BSD; blackside dace), Etheostoma sagitta (CAD; Cumberland arrow darter), and Etheostoma spilotum (KAD; Kentucky arrow darter). Etheostoma susanae (Cumberland darter) also is present in the study area but was too rare to model in this analysis. In this study, conducted by the U.S. Geological Survey in cooperation with the U.S. Fish and Wildlife Service, fish and habitat data were collected from 205 randomly selected stream sites in the upper Cumberland and Kentucky River Basins (120 and 85 sites, respectively) of Kentucky and Tennessee. Sites were sampled with 10 spatial replicates (2 meter x 5 meter electrofishing zones) to enable estimation of detection probabilities and environmental effects. The best models (that is, lowest Akaike information criterion scores) showed the effects of agriculture (negative) on occurrence of BSD and stream conductivity (negative) on occurrence of CAD and KAD. These effects were statistically more important than measures of basin area, elevation, and substrate size. Conductivity and agriculture showed nonlinear effects on species occurrence, and effects of conductivity were more precise above 400 microsiemens per centimeter than below this threshold. Models incorporated detection-level effects of electrofishing time (positive), flow velocity (negative), sand substrate (positive), and gravel/cobble substrate (negative). Models accounting for detection of BSD estimated occupancy rates similar to the observed proportion of occupied sites (0.10), but the best-supported models for CAD and KAD increased expected occupancy by about 4 percent for each species (from 0.17 to 0.21 for CAD and from 0.07 to 0.11 for KAD). Results of this study provide new inferences for modeling stream fish occurrence and detection processes and highlight the importance of continued monitoring and assessment of rare fish species in Appalachian headwater streams.

Kentucky, Tennessee, Virginia↗

USGS2019

Estimated use of water in the Cumberland River watershed in 2010 and projections of public-supply water use to 2040

The U.S. Army Corps of Engineers (USACE), Nashville District, is conducting ongoing water-supply analyses of USACE reservoirs in the Cumberland River watershed to identify areas where potential water-resources issues may arise in the future. To assist the USACE in their efforts, the U.S. Geological Survey, in cooperation with the USACE, collected and analyzed water-use data to estimate public-supply, self-supplied industrial, irrigation, and thermoelectric water use for 2010 and to project water demand to 2040 for the Cumberland River watershed area. Estimates of water use for public supply were projected in 10-year increments through 2040 and were based on 2010 public water-supply data and population projections for 2020 to 2040. Additionally, estimates of consumptive use, wastewater releases, and thermoelectric power and industrial return flows were calculated. All estimates are presented for the entire watershed and for the 10 reservoir catchment areas (RCAs) within the watershed. Estimated water withdrawals in the Cumberland River watershed during 2010 averaged 3,456.23 million gallons per day (Mgal/d) of freshwater for offstream use. Return flow was estimated to be 3,370.08 Mgal/d, or 98 percent of the water withdrawn during 2010. Total consumptive use accounts for the remaining 2 percent, or 86.2 Mgal/d. Estimates of water withdrawals by source indicate that withdrawals from surface water during 2010 accounted for more than 99 percent of the total withdrawals, or 3,437.90 Mgal/d. Total groundwater withdrawals during 2010 were 18.33 Mgal/d, or less than 1 percent of the total withdrawals. During 2010, withdrawals by category were estimated as follows: thermoelectric power, 3,051.12 Mgal/d; public supply, 360.00 Mgal/d; industrial, 31.5 Mgal/d; and irrigation, 13.6 Mgal/d. Return flows were estimated as thermoelectric power, 3,051.06 Mgal/d, and industrial and public supply, 319.02 Mgal/d. Consumptive use was estimated as thermoelectric power, 0.06 Mgal/d; industrial and public supply, 72.5 Mgal/d; and irrigation, 13.6 Mgal/d. By 2040, the public supply of raw and (or) finished water to meet demand for the 10 RCAs is projected to increase 48 percent to 532.51 Mgal/d. This projected increase includes an increase from 51.5 to 72.5 Mgal/d, or 41 percent, in the Barkley RCA. The combined total water demand for the Cheatham, J. Percy Priest, and Old Hickory RCAs is projected to increase from 224.08 to 359.58 Mgal/d, or 61 percent. The combined total water demand for the Center Hill, Cordell Hull, and Dale Hollow RCAs is projected to increase from 31.7 to 43.0 Mgal/d, or 36 percent. The combined total water demand for the Martins Fork, Laurel, and Wolf Creek RCAs is projected to increase from 52.8 to 57.4 Mgal/d, or 9 percent. The only RCA in the watershed with a projected decrease in water demand is Martins Fork.

Kentucky, Tennessee, Virginia↗

USGS2014

The geochemistry of oils and gases from the Cumberland overthrust sheet in Virginia and Tennessee

This study presents high-resolution gas chromatograms of oils and molecular and isotopic analyses of oil-associated gases from 17 wells producing in the Upper Cambrian to Lower Ordovician Knox Group, the Middle and Upper Ordovician Stones River Group, and the Upper Ordovician Trenton Limestone in the Cumberland overthrust sheet. The wells are located in the Ben Hur and Rose Hill fields in Lee County, Va., and in the Swan Creek field in Hancock and Claiborne Counties, Tenn. They produce oils typical of those from source rocks that are rich in Gloeocapsomorpha prisca ( G. prisca ) (Assemblage A-type kerogen). The Rose Hill oils appear to come from a source that contains a higher proportion of Assemblage A-type kerogen than the Ben Hur and Swan Creek oils. Extrapolation of the δ 13 C compositions of oil-associated gases to possible kerogen compositions gives estimates of -23 to -24 per mil within the range of isotopic compositions of known G. prisca source material. Gases produced from the Knox Group wells in the Swan Creek field are different from those in the Middle and Upper Ordovician reservoirs and come from a source with a broader range of isotopic values. Trends in isotopic and gasoline-range compositional parameters of the oils and associated gas isotopic and molecular compositions are most likely influenced by changes in local source depositional facies.

Kentucky, Tennessee, Virginia↗

USGS1971

Fluid-inclusion evidence on the environment of formation of mineral deposits of the southern Appalachian valley

Approximately 1,330 fluid inclusions were studied in samples of ore and gangue minerals from both massive ore and late-stage vugs from a series of Appalachian deposits and five active mines in the East Tennessee zinc districts. Most primary inclusions in sphalerite, fluorite, dolomite, and quartz from East Tennessee homogenized at 82 degrees -149 degrees C. Most primary inclusions in fluorite, barite, and sphalerite from the Central Kentucky, Central Tennessee, and Sweetwater barite districts, ranged from 72 degrees -132 degrees C. Pressure corrections to be added are probably less than 10 degrees C.Freezing data were obtained as a crude measure of the salinity of the inclusion fluids. With few exceptions, all primary inclusions contained very strongly saline brines (mostly >20 weight percent salts), with appreciable amounts of at least some salts other than NaCl, and some contained immiscible globules of oil. The exceptions include several quartz, fluorite, calcite, and barite samples that contained only moderately saline brines (12-16 percent), and some inclusions containing essentially fresh water, in vug calcite. Secondary inclusions had lower salinities than adjacent primaries. Eight primary inclusions in the differently colored outer millimeter of one Central Kentucky fluorite had low salinity (4-6 percent).The data indicate that all these deposits formed from hot, saline brines, with sphalerite forming from slightly hotter and more saline fluids than later gangue minerals. This places severe restrictions on possible modes of origin and makes deeply circulating connate brines the most probable ore fluids. The data give no information on the cause or direction of fluid circulation, which would be controlled by topography, salinity, and temperature during ore deposition, and they permit wide latitude in the construction of possible models. Other observations, on "colloform" textures, seem to indicate the admixture of at least small amounts of surface waters with the brines.

Kentucky, Tennessee, Virginia↗