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Research about Alabama

Source-linked reports with geographic coverage including Alabama.

At least 181 records · Page 10Linked to original sources
USGS1989

Geochemical and paleoenvironmental variations across the Cretaceous/Tertiary boundary at Braggs, Alabama

The Cretaceous/Tertiary (K/T) boundary in southern Alabama occurs in a sequence of interbedded shallow-marine limestones and marls deposited during a Late Maastrichtian regression and subsequent Danian transgression. The presence of a diverse assemblage of Cretaceous and Paleocene benthic micro- and macrofossils has allowed detailed examination of paleoenvironmental changes in this shallow-marine setting at the time of the K/T boundary extinctions. Although extensive diagenesis has resulted in the recrystallization and cementation of whole rock carbonate, a few molluscan macrofossils have retained their original calcitic structure. The oxygen isotopic record of these macrofossils shows a gradual cooling of 2–3°C over a 3 m.y. period which began in the late Maastrichtian and continued into the Danian. The characteristic depletion in δ 13 C across the K/T boundary displayed by planktonic microfossils from pelagic sequences is not recorded at Braggs. Major changes in whole rock trace and minor element chemistry reflect the decrease in terrigenous mineral fluxes to this location brought about by the rapid Early Paleocene transgression.

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USGS1989

Water resources data for Alabama, water year 1988

The Water Resources Division of the U.S. Geological Survey, in cooperation with State and Federal agencies, obtains a large amount of data pertaining to the water resources of Alabama each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data - Alabama."

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USGS1989

Mineralogy and paragenesis of the McAllister Sn-Ta-bearing pegmatite, Coosa County, Alabama

The McAllister Sn-Ta deposit (Alabama) is localized in a complex pegmatite that contains large zones of mineralized late-stage replacement-type saccharoidal albite and nearly monomineralic muscovite 'greisen-like' pipes. The dyke is at least 450 m long and averages approximately 9 m in thickness. At least two 'greisen-like' pipes, as much as 7.6 m by 4.5 m in cross-section and extending at least 76 m down a steep easterly pitch, occur near the center of the dyke. The dyke is hosted by an approximately 300-Ma-old pluton of a group referred to as the Rockford Granite, a mesozonal to epizonal two-mica, peraluminous tin-bearing granite. The pluton is genetically affiliated with a well-defined sequence of simple to complex pegmatite dykes and quartz-casiterite veins that occur near its margin and within the immediately adjacent metasedimentary rocks of the Wedowee Group.

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USGS1988

Northern Alabama colonies of the endangered grey bat Myotis grisescens: organochlorine contamination and mortality

From 1976 to 1986, dead and dying grey bats Myotis grisescens and grey bat guano were collected from caves along the Tennessee River in northern Alabama to determine the possible role of organochlorine chemicals — in particular wastes from a former DDT manufacturing plant near Huntsville—in the mortalities. Concentrations of chemical residues in brains were less than known lethal levels; certain observations and analyses did indicate the possibility of past organochlorine-induced bat deaths. Levels of contaminants in bats declined slowly during the 10-year sampling period, but heavy residue burdens persist. The high ratio of DDD to DDE in residues from the former DDT plant made them identifiable as far as 140 km downriver. Grey bats concentrated chemical residues to higher levels and demonstrated the presence of these residues over much greater distances than did red-winged blackbirds Agelaius phoenicus . Grey bats may be the most sensitive indicator available for monitoring the contamination from this former DDT manufacturing site.

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USGS1988

Water resources data for Alabama, water year 1987

The Water Resources Division of the U.S. Geological Survey, in cooperation with State and Federal agencies, obtains a large amount of data pertaining to the water resources of Alabama each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data - Alabama."

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USGS1988

Use of GIS technologies in addressing resource management problems in Mobile Bay, Alabama

Geographic Information Systems (GIS) technologies are being used in three neutral resource management studies of Mobile Bay, AL. Each study is briefly discussed. In the first, the GIS was used to analyze wetland habitat changes in the bay over a 25-year period. In the second, cartographic modeling techniques are being used to assess the potential impacts of contaminated sediments on selected resources in the bay. In the third, the GIS is part of a landscape level analysis of cumulative impacts in the bay. GIS applications can provide a spatial dimension to ecological problem-solving and a powerful tool for environmental planning and decisionmaking.

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USGS1987

Preliminary map showing landslides in Alabama

This map brings together data from all known reports on landslides in Alabama mentioned by Alger and Brabb (1985) and information provided by State and County Highway Departments in response to a questionnaire sent in 1981 by K. F. Rheams. Additional landslide data from the northern part of the state and from Jefferson County were added by Fred Taylor and E. E. Brabb from reports by Pomeroy (1982), Thomas (1979, 1982), and Szabo and others (1979). The locations of two landslides were provided by the U.S. Forest Service (written commun., 1982), and a few more additional landslide locations were noted by K. F. Rheams in 1981 and by E. E. Brabb in 1982. Locations of landslides from the various data sources were transferred to this map by measuring the distance from known landmarks. Substantial differences in scale, differential swelling and shrinking of paper source maps, and other technical problems in transferring the landslide data may have led to errors of as much as one mile in plotting the locations. The landslide locations, therefore, are located only approximately. Many more landslides exist in Alabama but have not yet been recognized or recorded in public documents. The absence of a landslide symbol on this map, therefore, does not indicate that an area is necessarily free of landslides. Conversely, the clustering of landslide symbols in an area should not be used to indicate that the area is unsafe, but rather that many landslides have been reported and that investigation of the problem by qualified geologists and engineers is prudent before development takes place. This map should be considered preliminary in the sense that a systematic evaluation of all areas in Alabama for landslides using standard photographic interpretation techniques has not yet been done. The user of this map is referred to Pomeroy and Thomas (1935) for a discussion of slope—stability problems in northern Alabama.

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USGS1987

Water resources data for Alabama, water year 1986

The Water Resources Division of the U.S. Geological Survey, in cooperation with State and Federal agencies, obtains a large amount of data pertaining to the water resources of Alabama each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data - Alabama."

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USGS1987

Geohydrology and susceptibility of major aquifers to surface contamination in Alabama; area 1

This report delineates and describes the geohydrology and susceptibility of the major aquifers to contamination in Area 1 - Colbert, Franklin, Lauderdale, Lawrence, Limeston, Madison, and Morgan Counties. Most of the area is underlain by a Mississippian carbonate sequence that includes two major aquifers, the Tuscumbia-Fort Payne aquifer and the Bangor aquifer. A third major aquifer, the Tuscaloosa aquifer of Cretaceous age, occurs in the southwest part of the area. The Mississippi carbonate aquifers are the Tuscumbia-Fort Payne aquifer which includes most Tuscumbia Limestone and the Fort Payne Chert, and a small area of the Monteagle Limestone, and the Bangor aquifer which includes the Bangor Limestone and Hartselle Sandstone. Both of these aquifers possess highly-variable secondary porosity and permeability related to fractures that have been enlarged, sometimes to cavernous proportions, due to solution processes. The Tuscaloosa aquifer consists of the Tuscaloosa Group, an unconsolidated clastic deposit that has relatively uniform primary porosity and permeability. Significant quantities of groundwater are available from each of the aquifers. Water levels at nearly 2 ,000 wells indicate that, for each aquifer, general groundwater movement is from topographically high to low areas. Each of the aquifers is recharged throughout its outcrop in the study area and is susceptible to contamination within the outcrop. Generalized topographic settings such as closed-contour depressions are identified as areas that are highly susceptible to contamination. Specific features such as sinkholes also are identified as extremely susceptible to contamination.

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USGS1987

Geohydrology and susceptibility of major aquifers to surface contamination in Alabama; area 7

The geohydrology and susceptibility of the seven major aquifers to surface contamination in Area 7 - Bibb, Dallas, Hale, Perry, and Wilcox Counties, are described. Aquifers in the northern part of the study area are in Paleozoic limestones and dolomite formations. Deposits in the central part of the study area are predominately of Cretaceous age and contain the Coker, Gordo, and Eutaw aquifers. Although the southern part of the study area has many deposits of Tertiary age, the Ripley Formation of Cretaceous age is the major aquifer. Contamination of any of the major aquifers is improbable because the majority of the recharge area for the primary aquifers is woodland, pasture, or farmland. Downdip from their outcrops, the major aquifers in the study area are protected from land surface contamination by relatively impermeable layers of clay and chalk. The aquifers that are highly susceptible to contamination are the ones in the limestone and dolomite formations in northern Bibb County. Sinkholes exist in the recharge area of these formations and could provide a direct link for contaminates from the land surface to the water table. An area northeast of the Selma well field is also highly susceptible to contamination. The Eutaw Formation in this area is overlain by alluvial deposits that could increase recharge to the aquifer by slowing the runoff rate of surface water.

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USGS1987

Geohydrology and susceptibility of major aquifers to surface contamination in Alabama; area 9

This report delineates and describes the geohydrology and susceptibility of the major aquifers to contamination in Area 9 - Barbour, Bullock, Macon, Pike, and Russell Counties. The major aquifers in the study area are the Tuscaloosa, Eutaw, and Providence-Ripley aquifers of Cretaceous age; and the Nanafalia-Clayton aquifer of Tertiary age. The five counties constitute the primary recharge area for the aquifers which are the source of public supplies in the study area. The total withdrawals of groundwater for all uses in 1986 were estimated to be about 14 million gallons per day. Areas of water level declines in the Tuscaloosa aquifer have developed near Eufaula and Union Springs. Water levels in the Eutaw aquifer have declined at Union Springs. All recharge areas for the major aquifers are susceptible to contamination from the surface. Shallow wells in the outcrop area are most susceptible.

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USGS1986

Water resources data for Alabama, water year 1985

Water resources data for the 1985 water year for Alabama consist of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels in wells. This report includes records on both surface and ground water in the State. Specifically, it contains: (1) Discharge records for 86 streamflow-gaging stations, for 62 partial-record or miscellaneous streamflow stations, and for 4 crest-stage or partial-record streamflow stations; (2) stage and content records for 13 lakes and reservoirs and stage at 27 stations; (3) water-quality records for 22 streamflow-gaging stations, for 66 ungaged streamsites, and for 7 wells; and (4) water-level records for 62 observation wells. Discharge records for a few pertinent stations in bordering States are also included in this report.

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USGS1985

Data collection for a time-of-travel and dispersion study on the Coosa River near Childersburg, Alabama

Approximately 2,300 dye-tracer samples were collected and analyzed during a 5-day time-of-travel study on a 23-mile reach of the Coosa River between Logan Martin and Lay dams near Childersburg, Alabama, October 27 to 31, 1984. Rhodamine WT was used as the tracer-dye. Unsteady flow conditions prevailed in the study reach. The rate of movement of the dye cloud between sampling cross sections ranged from 0.15 to 1.36 feet per second. The average rate of movement of the dye cloud between the injection cross section and the downstream sampling cross section was 0.42 foot per second.

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