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Sample records for alaskan coastal plain

  1. InSAR detects possible thaw settlement in the Alaskan Arctic Coastal Plain

    USGS Publications Warehouse

    Rykhus, R.P.; Lu, Zhiming

    2008-01-01

    Satellite interferometric synthetic aperture radar (InSAR) has proven to be an effective tool for monitoring surface deformation from volcanoes, earthquakes, landslides, and groundwater withdrawal. This paper seeks to expand the list of applications of InSAR data to include monitoring subsidence possibly associated with thaw settlement over the Alaskan Arctic Coastal Plain. To test our hypothesis that InSAR data are sufficiently sensitive to detect subsidence associated with thaw settlement, we acquired all Japanese Earth Resources Satellite-1 (JERS-1) L-band data available for the summers of 1996, 1997, and 1998 over two sites on the Alaska North Slope. The least amount of subsidence for both study sites was detected in the interferograms covering the summer of 1996 (2-3 cm), interferograms from 1997 and 1998 revealed that about 3 cm of subsidence occurred at the northern Cache One Lake site, and about 5 cm of subsidence was detected at the southern Kaparuk River site. These preliminary results illustrate the capacity of the L-band (24 cm) wavelength JERS-1 radar data to penetrate the short Arctic vegetation to monitor subsidence possibly associated with thaw settlement of the active layer and (or) other hydrologic changes over relatively large areas. ?? 2008 CASI.

  2. Changes in Thaw Lake Morphometry on the Barrow Peninsula, Alaskan Arctic Coastal Plain, 1955-2002

    NASA Astrophysics Data System (ADS)

    Jones, B. M.; Hinkel, K. M.; Eisner, W. R.; Peterson, K. M.; Frohn, R. C.; Beck, R. A.

    2005-12-01

    Since the early 1950s, there have been several studies of thaw lakes on the Barrow Peninsula of northern Alaska that focused largely on lake orientation and morphometry. To date, a comprehensive examination of changes in lake area has not been conducted. Lake expansion can result from shoreline erosion and ground subsidence as permafrost thaws. Lake area reduction occurs in response to complete or partial drainage triggered by infilling, stream activity, or coastal erosion. This study examines the changes in lake area (those >10 hectares) over the period 1955 to 2002. The 1955 data was obtained by digitizing lakes from a digital raster graphic of the 1:63360 scale U.S.G.S. topographic map derived from 1955 aerial survey photography. More recently, lakes were identified on high-resolution ORRI and IFSAR data collected in 2002. During this period, total lake area decreased from 22.0% to 20.8%. The number of lakes decreased by 72, from 337 to 265, and average lake size increased from 139 ha in 1955 to 166 ha in 2002. These changes resulted from lake coalescence, or from partial drainage that reduced lake area below the 10 ha threshold. Of the 72 lakes that are no longer larger than 10 hectares, 22 have completely drained. It appears that 16 have drained by natural causes (headward erosion by streams or coastal erosion) and 6 have drained as a result of human disturbance. There are 4 lakes in 2002 that were not present in 1955; these appear to have resulted from the merger of smaller lakes. By increasing the size of interest to 40 ha to focus on larger lakes, the same general trend is observed. There are currently fewer lakes larger than 40 ha, average lake size has increased, yet aerial coverage of lakes larger than 40 ha has decreased. These results contrast to recent findings reported by Smith and colleagues for large lakes in the continuous permafrost zone of Siberia.

  3. ERTS imagery applied to Alaskan coastal problems. [surface water circulation

    NASA Technical Reports Server (NTRS)

    Wright, F. F.; Sharma, G. D.; Burbank, D. C.; Burns, J. J.

    1974-01-01

    Along the Alaska coast, surface water circulation is relatively easy to study with ERTS imagery. Highly turbid river water, sea ice, and fluvial ice have proven to be excellent tracers of the surface waters. Sea truth studies in the Gulf of Alaska, Cook Inlet, Bristol Bay, and the Bering Strait area have established the reliability of these tracers. ERTS imagery in the MSS 4 and 5 bands is particularly useful for observing lower concentrations of suspended sediment, while MSS 6 data is best for the most concentrated plumes. Ice features are most clearly seen on MSS 7 imagery; fracture patterns and the movement of specific floes can be used to map circulation in the winter when runoff is restricted, if appropriate allowance is made for wind influence. Current patterns interpreted from satellite data are only two-dimensional, but since most biological activity and pollution are concentrated near the surface, the information developed can be of direct utility. Details of Alaska inshore circulation of importance to coastal engineering, navigation, pollution studies, and fisheries development have been clarified with satellite data. ERTS has made possible the analysis of circulation in many parts of the Alaskan coast.

  4. Studies of the Northern Alaskan Coastal System: Ongoing project work and synthesis activities

    NASA Astrophysics Data System (ADS)

    Douglas, T. A.; Sturm, M.; Ashjian, C. J.; Jorgensen, T.; Oechel, W. C.; Ping, C.; Rhew, R. C.; Stieglitz, M.

    2006-12-01

    Six ongoing projects focus on a better understanding of processes occurring along the Arctic Alaskan Coast. These projects, grouped as "Studies of the Northern Alaskan Coastal System", or SNACS, combine field, laboratory, modeling and human dimensions research. They include: 1) an investigation of climate variability, ocean processes, sea ice, bowhead whales, and Inupiat subsistence whaling, 2) research on the impact of variability within the ocean and atmosphere on terrestrial fluxes of carbon dioxide, dissolved organic matter and energy, 3) an inventory and description of soil organic carbon fluxes and ground ice in the coastal environment, 4) a determination of whether arctic coastal terrestrial ecosystems are significant sources or sinks of atmospheric methyl halides, chloroform and methane, 5) development of generalized discharge- constituent relationships for arctic basins, and 6) an investigation of the processes controlling mercury deposition to the coastal system. Three broad themes unite the projects: 1) nutrient fluxes from rivers and shoreline erosion in the Arctic coastal zone, 2) impacts of cryospheric changes on the Alaskan Arctic Coast, and 3) potential rapid regime shifts controlled by atmospheric and meteorological processes that could affect the Alaskan Arctic Coast. Warming of the Arctic, particularly its impact on sea ice and nutrient transport in arctic rivers is already affecting fundamental coastal system processes. The six SNACS projects are helping to understand how these impacts will evolve and what their ramifications will be both within and outside of the Arctic.

  5. A pleistocene sand sea on the Alaskan arctic coastal plain

    USGS Publications Warehouse

    Carter, L.D.

    1981-01-01

    A ridge and thermokarst-basin landscape that is strikingly portrayed in Landsat winter imagery consists of large Pleistocene dunes that have been modified by younger eolian activity and thermokarst processes. This is the most extensive area of large stabilized dunes yet reported in the North American Arctic; the landscape is of particular interest because it has been proposed as a first-order analogfor martian fretted terrain. Recognition ofthe large dunes permits a new interpretation for linear and curvilinear trends visible in Landsat summer imagery.

  6. A Pleistocene Sand Sea on the Alaskan Arctic Coastal Plain

    NASA Astrophysics Data System (ADS)

    Carter, L. David

    1981-01-01

    A ridge and thermokarst-basin landscape that is strikingly portrayed in Landsat winter imagery consists of large Pleistocene dunes that have been modified by younger eolian activity and thermokarst processes. This is the most extensive area of large stabilized dunes yet reported in the North American Arctic; the landscape is of particular interest because it has been proposed as a first-order analog for martian fretted terrain. Recognition of the large dunes permits a new interpretation for linear and curvilinear trends visible in Landsat summer imagery.

  7. Chinese Tallow: Invading the Southeastern Coastal Plain

    USGS Publications Warehouse

    U.S. Geological Survey

    2000-01-01

    Chinese tallow is an ornamental tree with colorful autumn foliage that can survive full sunlight and shade, flooding, drought, and in some cases fire. To horticulturists this kind of tree sounds like a dream, but to ecologists, land managers, and land owners this kind of tree can be a nightmare, especially when it invades an area and takes over native vegetation. Chinese tallow (Triadica sebifera), a nonnative tree from China, is currently transforming the southeastern Coastal Plain. Over the last 30 years, Chinese tallow has become a common tree in old fields and bottomland swamps of coastal Louisiana. Several studies at the U.S. Geological Survey's National Wetlands Research Center (NWRC), Lafayette, Louisiana, are aimed at understanding the factors that contribute to Chinese tallow growth, spread, and management. When tallow invades, it eventually monopolizes an area, creating a forest without native animal or plant species. This tree exhibits classic traits of most nonnative invaders: it is attractive so people want to distribute it, it has incredible resiliency, it grows quickly and in a variety of soils, and it is resistant to pests. In the coastal prairie of Louisiana and Texas, Chinese tallow can grow up to 30 feet and shade out native sun-loving prairie species. The disappearing of prairie species is troublesome because less than 1% of original coastal prairie remains, and in Louisiana, less than 500 of the original 2.2 million acres still exist. Tallow reproduces and grows quickly and can cause large-scale ecosystem modification (fig. 1). For example, when it completely replaces native vegetation, it has a negative effect on birds by degrading the habitat. Besides shading out grasses that cattle like to eat, it can also be potentially harmful to humans and animals because of its berries (fig. 2) and plant sap that contain toxins. There is some concern its leaves may shed toxins that change the soil chemistry and make it difficult for other plants to grow.

  8. Alder Expansion as a Coastal Warming Signal - Linking Coastal Alaskan Carbon to Vegetation Change with Climate

    NASA Astrophysics Data System (ADS)

    Peteet, D. M.; Nichols, J. E.; Moy, C. M.; McGeachy, A.

    2014-12-01

    Corser Bog (60.5296364oN, 145.453858oW), 21 km east of Cordova, AK is a sphagnum-dominated peatland 42 m asl. adjacent to Sheridan Glacier and the Copper River Delta. Deglaciation at 11.5 ka began with shallow pond deposition, reflecting regional warmth with the pioneers Alnus crispa subsp. sinuata, Salix, and ferns colonizing the fresh, mineral soils on the landscape. Continued early Holocene warming/melting of glaciers led to the foundation species Alnus dominance and peatland formation, surrounded by shrubs such as Rubus spectabilis, Sambucus racemosa, and wetland species such as Myrica gale and Potentilla palustris. As Sphagnum peat accumulated, the highest rates of carbon accumulation for a few centuries are represented at 50 g/m2/a, similar to short-term very high rates in the early Holocene throughout the circumboreal region but varying within the early Holocene due to development of local wet, bryophytic environments. A shift to sedge peat regionally along the South-Central Alaskan coast 7.6 - 3.7 ka is paralleled by a more evaporative, drier climate with Rhododendron groenlandicum presence, lower carbon accumulation (13 g/m2/a), and minimal macrofossil preservation, which is paralleled regionally in coastal muskegs both to the northwest and southeast and by a hiatus in a nearby lake record. A cooler, moister climate is evident in Corser Bog with the shift to Sphagnum peat at 3.7 ka, regional shifts from sedge to Sphagnum peat throughout the entire coastline from Yakutat to Girdwood, AK and the demonstration of glacial advances in the region. Alnus pollen markedly increases to 60% in the uppermost sample, indicative of a major signal for glacial recession in this region.

  9. Chinese tallow: Invading the southeastern Coastal Plain

    USGS Publications Warehouse

    ,

    2000-01-01

    Chinese tallow is an ornamental tree with colorful autumn foliage that can survive full sunlight and shade, flooding, drought, and in some cases fire. To horticulturists this kind of tree sounds like a dream, but to ecologists, land managers, and land owners this kind of tree can be a nightmare, especially when it invades an area and takes over native vegetation. Chinese tallow (Triadica sebifera), a nonnative tree from China, is currently transforming the southeastern Coastal Plain.Over the last 30 years, Chinese tallow has become a common tree in old fields and bottomland swamps of coastal Louisiana. Several studies at the U.S. Geological Survey’s National Wetlands Research Center (NWRC), Lafayette, Louisiana, are aimed at understanding the factors that contribute to Chinese tallow growth, spread, and management.When tallow invades, it eventually monopolizes an area, creating a forest without native animal or plant species. This tree exhibits classic traits of most nonnative invaders: it is attractive so people want to distribute it, it has incredible resiliency, it grows quickly and in a variety of soils, and it is resistant to pests.In the coastal prairie of Louisiana and Texas, Chinese tallow can grow up to 30 feet and shade out native sun-loving prairie species. The disappearing of prairie species is troublesome because less than 1% of original coastal prairie remains, and in Louisiana, less than 500 of the original 2.2 million acres still exist.Tallow reproduces and grows quickly and can cause large-scale ecosystem modification (fig. 1). For example, when it completely replaces native vegetation, it has a negative effect on birds by degrading the habitat. Besides shading out grasses that cattle like to eat, it can also be potentially harmful to humans and animals because of its berries (fig. 2) and plant sap that contain toxins. There is some concern its leaves may shed toxins that change the soil chemistry and make it difficult for other plants to grow.

  10. BIOLOGICAL INTEGRITY IN MID-ATLANTIC COASTAL PLAINS HEADWATER STREAMS

    EPA Science Inventory

    The objective of this study was to assess the applicability of landscape metrics, in conjunction with stream water quality to estimate the biological integrity of headwater streams in the Mid-Atlantic Coastal Plains using multivariate techniques.

  11. The Virginia Coastal Plain Hydrogeologic Framework

    USGS Publications Warehouse

    McFarland, E. Randolph; Bruce, T. Scott

    2006-01-01

    A refined descriptive hydrogeologic framework of the Coastal Plain of eastern Virginia provides a new perspective on the regional ground-water system by incorporating recent understanding gained by discovery of the Chesapeake Bay impact crater and determination of other geological relations. The seaward-thickening wedge of extensive, eastward-dipping strata of largely unconsolidated sediments is classified into a series of 19 hydrogeologic units, based on interpretations of geophysical logs and allied descriptions and analyses from a regional network of 403 boreholes. Potomac aquifer sediments of Early Cretaceous age form the primary ground-water supply resource. The Potomac aquifer is designated as a single aquifer because the fine-grained interbeds, which are spatially highly variable and inherently discontinuous, are not sufficiently dense across a continuous expanse to act as regional barriers to ground-water flow. Part of the Potomac aquifer in the outer part of the Chesapeake Bay impact crater consists of megablock beds, which are relatively undeformed internally but are bounded by widely separated faults. The Potomac aquifer is entirely truncated across the inner part of the crater. The Potomac confining zone approximates a transition from the Potomac aquifer to overlying hydrogeologic units. New or revised designations of sediments of Late Cretaceous age that are present only south of the James River include the upper Cenomanian confining unit, the Virginia Beach aquifer and confining zone, and the Peedee aquifer and confining zone. The Virginia Beach aquifer is a locally important ground-water supply resource. Sediments of late Paleocene to early Eocene age that compose the Aquia aquifer and overlying Nanjemoy-Marlboro confining unit are truncated along the margin of the Chesapeake Bay impact crater. Sediments of late Eocene age compose three newly designated confining units within the crater, which are from bottom to top, the impact-generated Exmore clast

  12. Flood hydrology and methylmercury availability in coastal plain rivers.

    PubMed

    Bradley, Paul M; Journey, Celeste A; Chapelle, Francis H; Lowery, Mark A; Conrads, Paul A

    2010-12-15

    Mercury (Hg) burdens in top-predator fish differ substantially between adjacent South Carolina Coastal Plain river basins with similar wetlands coverage. In the Congaree River, floodwaters frequently originate in the Blue Ridge and Piedmont regions, where wetlands coverage and surface water dissolved methylmercury (MeHg) concentrations are low. Piedmont-driven flood events can lead to downward hydraulic gradients in the Coastal Plain riparian wetland margins, inhibiting MeHg transport from wetland sediments, and decreasing MeHg availability in the Congaree River habitat. In the adjacent Edisto River basin, floodwaters originate only within Coastal Plain sediments, maintaining upward hydraulic gradients even during flood events, promoting MeHg transport to the water column, and enhancing MeHg availability in the Edisto River habitat. These results indicate that flood hydrodynamics contribute to the variability in Hg vulnerability between Coastal Plain rivers and that comprehensive regional assessment of the relationship between flood hydrodynamics and Hg risk in Coastal Plain streams is warranted.

  13. Flood hydrology and methylmercury availability in Coastal Plain rivers

    USGS Publications Warehouse

    Bradley, Paul M.; Journey, Celeste A.; Chapelle, Francis H.; Lowery, Mark A.; Conrads, Paul A.

    2010-01-01

    Mercury (Hg) burdens in top-predator fish differ substantially between adjacent South Carolina Coastal Plain river basins with similar wetlands coverage. In the Congaree River, floodwaters frequently originate in the Blue Ridge and Piedmont regions, where wetlands coverage and surface water dissolved methylmercury (MeHg) concentrations are low. Piedmont-driven flood events can lead to downward hydraulic gradients in the Coastal Plain riparian wetland margins, inhibiting MeHg transport from wetland sediments, and decreasing MeHg availability in the Congaree River habitat. In the adjacent Edisto River basin, floodwaters originate only within Coastal Plain sediments, maintaining upward hydraulic gradients even during flood events, promoting MeHg transport to the water column, and enhancing MeHg availability in the Edisto River habitat. These results indicate that flood hydrodynamics contribute to the variability in Hg vulnerability between Coastal Plain rivers and that comprehensive regional assessment of the relationship between flood hydrodynamics and Hg risk in Coastal Plain streams is warranted.

  14. Stratigraphic and hydrogeologic framework of the Alabama Coastal Plain

    USGS Publications Warehouse

    Davis, M.E.

    1988-01-01

    Tertiary and Cretaceous sand aquifers of the Southeastern United States Coastal Plain comprise a major multlstate aquifer system informally defined as the Southeastern Coastal Plain aquifer system, which is being studied as part of the U.S. Geological Survey's Regional Aquifer System Analysis (RASA) program. The major objectives of each RASA study are to identify, delineate, and map the distribution of permeable clastlc rock, to examine the pattern of ground-water flow within the regional aquifers, and to develop digital computer simulations to understand the flow system. The Coastal Plain aquifers in Alabama are being studied as a part of this system. This report describes the stratlgraphlc framework of the Cretaceous, Tertiary, and Quaternary Systems in Alabama to aid in delineating aquifers and confining units within the thick sequence of sediments that comprises the Southeastern Coastal Plain aquifer system in the State. Stratigraphlc units of Cretaceous and Tertiary age that make up most of the aquifer system in the Coastal Plain of Alabama consist of clastlc deposits of Early Cretaceous age; the Coker and Gordo Formations of the Tuscaloosa Group, Eutaw Formation, and Selma Group of Late Cretaceous age; and the Midway, Wilcox, and Clalborne Groups of Tertiary age. However, stratigraphlc units of late Eocene to Holocene age partially overlie and are hydraulically connected to clastic deposits in southern Alabama. These upper carbonate and clastlc stratlgraphic units also are part of the adjoining Florldan and Gulf Coastal Lowlands aquifer systems. The Coastal Plain aquifer system is underlain by pre-Cretaceous rocks consisting of low-permeabillty sedimentary rocks of Paleozolc, Triassic, and Jurassic age, and a complex of metamorphic and igneous rocks of Precambrian and Paleozolc age similar to those found near the surface in the Piedmont physiographic province. Twelve hydrogeologlc units in the Alabama Coastal Plain are defined--slx aquifers and six confining

  15. Lineaments in coastal plain sediments as seen in ERTS imagery

    NASA Technical Reports Server (NTRS)

    Withington, C. F.

    1973-01-01

    Examination of satellite imagery over the Atlantic Coastal Plain near Washington, D. C. shows numerous lineaments, which cannot be accounted for by any known cultural or natural features. At least some of these lineaments represent the surface expression of faults, for one of them has been correlated with the outcrop of a fault that had been traced for several miles in southern Prince Georges County, Maryland. If a substantial number of these lineaments do indeed represent fault traces, the fact that they show on the surface suggests that the geologic history of the Coastal Plain is much more complex than has previously been recognized, and that faulting may have occurred in the Holocene, much later than has generally been recognized. The importance that such recent movements could have on future development of the Coastal Plain should be emphasized.

  16. The influence of the Alaskan Gyre on the coastal circulation in the Gulf of Alaska

    NASA Technical Reports Server (NTRS)

    Heim, Paul K., II; Johnson, Mark A.; O'Brien, James J.

    1992-01-01

    The circulation of the northeast Pacific Ocean and the Gulf of Alaska is simulated by means of a reduced-gravity wind-driven model to study seasonal and interannual flow variability. The circulation in the NE Pacific is discussed emphasizing its ramifications for the physical domain, equations, and boundary conditions of the numerical model. The pseudostress fields used to drive the model are based on 20 years of data from the Comprehensive Ocean-Atmosphere Data Set and are analyzed with empirical orthogonal function analysis. The monthly stresses from 1986-89 are used to drive the model, and regional oceanographic features are reproduced including the Alaskan Gyre, Coastal Current, the Sitka eddy, and a severe cyclonic eddy. Comparisons with experimental data show that the high-resolution baroclinic model is valid and demonstrates the applicability of reduced-gravity models.

  17. Coastal geomorphology of the Martian northern plains

    NASA Technical Reports Server (NTRS)

    Parker, Timothy J.; Gorsline, Donn S.; Saunders, Stephen R.; Pieri, David C.; Schneeberger, Dale M.

    1993-01-01

    The paper considers the question of the formation of the outflow channels and valley networks discovered on the Martian northern plains during the Mariner 9 mission. Parker and Saunders (1987) and Parker et al. (1987, 1989) data are used to describe key features common both in the lower reaches of the outflow channels and within and along the margins of the entire northern plains. It is suggested, that of the geological processes capable of producing similar morphologies on earth, lacustrine or marine deposition and subsequent periglacial modification offer the simplest and most consistent explanation for the suit of features found on Mars.

  18. 40 CFR 81.152 - Southern Coastal Plain Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Southern Coastal Plain Intrastate Air... Air Quality Control Regions § 81.152 Southern Coastal Plain Intrastate Air Quality Control Region. The Southern Coastal Plain Intrastate Air Quality Control Region (North Carolina) consists of the...

  19. 40 CFR 81.149 - Northern Coastal Plain Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Northern Coastal Plain Intrastate Air... Air Quality Control Regions § 81.149 Northern Coastal Plain Intrastate Air Quality Control Region. The Northern Coastal Plain Intrastate Air Quality Control Region (North Carolina) consists of the...

  20. SWAT application in low-gradient Coastal Plain landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low-gradient coastal plain watersheds present unique challenges for watershed modeling. Broad low-gradient floodplains with considerable in-stream vegetation contribute to low-velocity streamflow. In addition, direct interaction between streamflow and surficial aquifers must also be considered. H...

  1. BIOLOGICAL INTEGRITY IN MID-ATLANTIC COASTAL PLAINS HEADWATER STREAMS

    EPA Science Inventory

    The objective of this study was to assess the applicability of using landscape variables in conjunction with water quality and benthic data to efficiently estimate stream condition of select headwater streams in the Mid-Atlantic Coastal Plains. Eighty-two streams with riffle sit...

  2. Land Cover Trends in the Southern Florida Coastal Plain

    USGS Publications Warehouse

    Kambly, Steven; Moreland, Thomas R.

    2009-01-01

    This report presents an assessment of land use and land cover change in the Southern Florida Coastal Plain ecoregion for the period from 1973 to 2000. The ecoregion is one of 84 level III ecoregions defined by the Environmental Protection Agency; ecoregions have been designed to serve as a spatial framework for environmental resource management and denote areas that contain a geographically distinct assemblage of biotic and abiotic phenomena, including geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The Southern Florida Coastal Plain ecoregion covers an area of approximately 22,407 square kilometers [8,651 square miles] across the lower portion of the Florida peninsula, from Lake Okeechobee southward through the Florida Keys. It comprises flat plains with wet soils, marshland and swamp land cover with Everglades and palmetto prairie vegetation types.

  3. Arctic Refuge coastal plain terrestrial wildlife research summaries

    USGS Publications Warehouse

    Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

    2002-01-01

    In 1980, when the U.S. Congress enacted the Alaska National Interest Lands Conservation Act (ANILCA), it also mandated a study of the coastal plain of the Arctic National Wildlife Refuge. Section 1002 of ANILCA stated that a comprehensive inventory of fish and wildlife resources would be conducted on 1.5 million acres of the Arctic Refuge coastal plain (1002 Area). Potential petroleum reserves in the 1002 Area were also to be evaluated from surface geological studies and seismic exploration surveys. Results of these studies and recommendations for future management of the Arctic Refuge coastal plain were to be prepared in a report to Congress. In 1987, the Department of the Interior published the Arctic National Wildlife Refuge, Alaska, Coastal Plain Resource Assessment - Report and Recommendations to the Congress of the United States and Final Environmental Impact Statement. This report to Congress identified the potential for oil and gas production (updated* most recently by the U.S. Geological Survey in 2001), described the biological resources, and evaluated the potential adverse effects to fish and wildlife resources. The 1987 report analyzed the potential environmental consequences of five management alternatives for the coastal plain, ranging from wilderness designation to opening the entire area to lease for oil and gas developement. The report's summary recommended opening the 1002 Area to an orderly oil and gas leasing program, but cautioned that adverse effects to some wildlife populations were possible. Congress did not act on this recommendation nor any other alternative for the 1002 Area, and scientists continued studies of key wildlife species and habitats on the coastal plain of the Arctic Refuge and surrounding areas. This report contains updated summaries of those scientific investigations of caribou, muskoxen, predators (grizzly bears, wolves, golden eagles), polar bears, snow geese, and their wildlife habitats. Contributions to this report were

  4. Hydrogeologic Framework of the New Jersey Coastal Plain

    USGS Publications Warehouse

    Zapecza, Otto S.

    1989-01-01

    This report presents the results of a water-resources, oriented subsurface mapping program within the Coastal Plain of New Jersey. The occurrence and configuration of 15 regional hydrogeologic units have been defined, primarily on the basis of an interpretation of borehole geophysical data. The nine aquifers and six confining beds are composed of unconsolidated clay, silt, sand, and gravel and range in age from Cretaceous to Quaternary. Electric and gamma-ray logs from more than 1,000 Coastal Plain wells were examined. Of these, interpretive data for 302 sites were selected, on the basis of logged depth, quality of data, and data distribution, to prepare structure contour and thickness maps for each aquifer and a thickness map for each confining bed. These maps, together with 14 hydrogeologic sections, show the geometry, lateral extent, and vertical and horizontal relationships among the 15 hydrogeologic units. The hydrogeologic maps and sections show that distinct lower, middle, and upper aquifers are present within the Potomac, Raritan-Magothy aquifer system near the Delaware River from Burlington County to Salem County. Although the lower aquifer is recognized only in this area, the middle aquifer extends into the northeastern Coastal Plain of New Jersey, where it is stratigraphically equivalent to the Farrington aquifer. The upper aquifer extends throughout most of the New Jersey Coastal Plain and is stratigraphically equivalent to the Old Bridge aquifer in the northeastern Coastal Plain. The overlying Merchantville-Woodbury confining bed is the most regionally extensive confining bed within the New Jersey Coastal Plain. Its thickness ranges from less than 100 feet near the outcrop to more than 450 feet along the coast. The Englishtown aquifer system acts as a single aquifer throughout most of its subsurface extent, but it contains two water-bearing sands in pars of Monmouth and Ocean Counties. The overlying Marshalltown-Wenonah confining bed is a thin, leaky

  5. River diversions, avulsions and captures in the Tortuguero coastal plain

    NASA Astrophysics Data System (ADS)

    Galve, Jorge Pedro; Alvarado, Guillermo; Pérez Peña, José Vicente; Azañón, José Miguel; Mora, Mauricio; Booth-Rea, Guillermo

    2016-04-01

    The Tortuguero area is a coastal plain that forms part of the North Limón sedimentary basin, the back-arc region of the Caribbean side of Costa Rica. This coastal plain is characterised by an abnormal drainage pattern with river captures, diversions and shifts in channel directions. We are analyzing this anomalous drainage network adopting a classical geomorphological approach combined with geomorphometric techniques. The SRTM DEM at 1 arc-second of resolution (~30 m) from NASA, topographic maps 1:50,000, satellital images and the digital cartography of the drainage network have been used for inventorying the channel pattern anomalies. River segments were categorized according to sinuosity, orientation, slope changes and incision using GIS tools. Initially, anomalies in the analyzed river courses suggested that buried thrust fronts could disrupt their natural pattern. However, we have not identified any evidence to link the activity of buried structures with the disruption of natural drainage. Blind thrusts detected through seismic subsurface exploration in the SE sector of the Tortuguero plain do not seem to produce changes in the sinuosity, orientation, slope and incision of rivers as those observed in the deeply studied tectonically active area of the Po Plain (Italy). The identified river pattern anomalies have been explained due to other alternative causes: (1) the migration of the mouths of Reventazón, Pacuare and Matina rivers is produced by sand sedimentation in the coast because of a successive ridge beach formation. This migration to the SE has the same direction than the main ocean currents those deposited the sand. (2) The anomalous course of Parismina river is most probably conditioned by the fracturation of the dissected volcanic apron of Turrialba volcano. (3) Channel migration and capture of Barbilla river by Matina river can be triggered by the tectonic tilting of the coastal plain towards the SE. The subsidence of the SE sector of the plain was

  6. Groundwater quality in the Santa Barbara Coastal Plain, California

    USGS Publications Warehouse

    Davis, Tracy A.; Belitz, Kenneth

    2016-10-03

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California established the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The Santa Barbara Coastal Plain is one of the study units.

  7. Hydrogeologic conditions in the coastal plain of New Jersey

    USGS Publications Warehouse

    Vowinkel, Eric F.; Foster, W. Kendall

    1981-01-01

    A wedge-shaped mass of unconsolidated sediments composed of alternating layers of clay, silt, sand, and gravel underlies the Coastal Plain of New Jersey. The hydrologic units of this mass vary in thickness, lateral extent, lithology, and water-bearing characteristics. Some of the units act as aquifers, whereas other units act as confining layers. The entire sediment wedge is almost an independent and isolated hydrologic system. Components of the long-term hydrologic budget for the Coastal Plain are precipitation, streamflow, and water loss. Under natural conditions, average precipitation is about 44 inches per year; while streamflow and water loss are about 20 and 24 inches per year, respectively. More than 75 percent of the streamflow in the Coastal Plain is derived from ground-water runoff. Some activities of man have modified the natural hydrologic cycle in the Coastal Plain. The primary activity affecting the system has been the withdrawal of ground water. Major changes in the flow patterns of water in several aquifers have been recognized during the past few decades partially as a result of increasing ground-water withdrawal. Where head gradients are large enough, water can be induced to flow from adjacent surface-water bodies or through confining beds. Induced recharge from the Delaware River to the Potomac-Raritan-Magothy aquifer system is occurring as a result of pumping stresses in the outcrop area of the aquifer. Recharge from the river to the aquifer from Salem to Burlington County was estimated to be about 113 cubic feet per second in 1978. (USGS)

  8. Groundwater Quality in the Santa Barbara Coastal Plain, California

    USGS Publications Warehouse

    Davis, T.A.; Belitz, Kenneth

    2016-10-03

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California established the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The Santa Barbara Coastal Plain is one of the study units.

  9. Hydrologic Controls On Methylmercury Availability In Coastal Plain Rivers

    NASA Astrophysics Data System (ADS)

    Bradley, P. M.; Brigham, M. E.; Burns, D. A.; Button, D. T.; Lutz, M. A.; Marvin-DiPasquale, M. C.; Riva-Murray, K.; Journey, C.

    2011-12-01

    Methylmercury (MeHg) in streams is often attributed to methylation in up-gradient wetland areas, with episodic flood events maximizing wetland-stream hydrologic connectivity and dominating MeHg supply to the stream habitat. A number of studies have demonstrated that Coastal Plain streams in the southeastern United States are particularly vulnerable to high MeHg bioaccumulation and have attributed this vulnerability to wetland abundance and strong hydrologic connectivity between wetland areas and adjacent stream aquatic habitat. Because characteristically coarse-grained Coastal Plain sediments favor vertical infiltration with little surface runoff, flood events attributable to Coastal Plain precipitation are driven by rising groundwater, promoting efficient transport of MeHg from wetland/floodplain source areas to the stream habitat and increasing in-stream availability. Several observations at McTier Creek, South Carolina, however, suggest that good hydrologic connectivity and efficient MeHg transport in Coastal Plain systems are not limited to flood conditions. Close correspondence between stream and shallow-groundwater water levels at McTier indicate good hydrologic connectivity exists prior to flood conditions. Dissolved MeHg concentrations do not increase under flood conditions. Thus, we assessed the flux of water and dissolved mercury (Hg) species (FMeHg and total Hg (FTHg)) from surface water and groundwater sources in a short reach at McTier Creek during separate events in April and July 2009, to determine the importance of shallow groundwater Hg transport from floodplain areas to the stream under non-flood conditions. Mass balance assessments indicated that, under non-flood conditions, the primary supply of water, FMeHg, and FTHg within the reach (excluding upstream surface-water influx) was groundwater discharge, rather than tributary transport from wetlands, in-stream MeHg production, or atmospheric deposition. The results indicate efficient transport of

  10. Geochemistry of the northern Atlantic Coastal Plain aquifer system

    USGS Publications Warehouse

    Knobel, L.L.; Chapelle, F.H.; Meisler, Harold

    1998-01-01

    Sediments of the northern Atlantic Coastal Plain comprise a complex multiaquifer flow system. On a large scale (greater than 500 square miles) ground water in this system evolves from predominantly calcium magnesium bicarbonate water with a low dissolved-solids content and low pH, near outcrop-recharge areas, to predominantly sodium bicarbonate water with a high-dissolved solids content and high pH, downgradient. This sodium bicarbonate water then grades into a sodium chloride water. This large-scale predictable progression of hydrochemical facies results from the summation of many smaller scale geochemical processes that chiefly depend on the sedimentary depositional environments of the aquifers.

  11. Carbon Sources and Sinks in Freshwater and Estuarine Environments of the Arctic Coastal Plain.

    NASA Astrophysics Data System (ADS)

    Lougheed, V.; Tarin, G.; Tweedie, C. E.

    2015-12-01

    The source, fate and transport of terrestrially derived carbon as it moves through multiple landscape components (i.e. groundwater, rivers, ponds, wetlands, lakes, lagoons) on a path from land to sea in permafrost-dominated watersheds is poorly understood. Critical to our understanding of Arctic carbon budgets are small, but numerically abundant watersheds that dominate the landscape of the Alaskan Arctic Coastal Plain (ACP), which appears to be changing rapidly in response to climate warming and other environmental changes. This study was designed to understand the contribution of freshwater ecosystems in the Arctic to regional carbon budgets. pCO2 was logged continually in ponds, lakes and streams sites near Barrow, AK and recorded across transects in Elson Lagoon, a coastal lagoon on the Beaufort coast. Average pCO2 of the pond over 2 weeks in August (1196 μatm) was double that of lakes and streams, and four times higher than Elson Lagoon (216 μatm); thus, the Lagoon was acting as a small sink while the pond was a substantial source of CO2 to the atmosphere. The uptake of CO2 in Elson Lagoon, combined with an oversaturation of O2, may be due to enhanced primary productivity caused by freshwater nutrient inputs. Conversely, pCO2, chlorophyll-a and DOC increased substantially in the pond after a large rain event, suggesting that run-off introduced large amounts of terrestrially-derived carbon from groundwater. Further studies are required to elucidate the fate and transport of carbon in the numerically abundant smaller watersheds of the Arctic.

  12. Hydrogeologic framework of the North Carolina Coastal Plain aquifer system

    USGS Publications Warehouse

    Winner, M.D.; Coble, R.W.

    1989-01-01

    The hydrogeologic framework of the North Carolina Coastal Plain aquifer system consists of ten aquifers separated by nine confining units. From top to bottom the aquifers are: the surficial aquifer, Yorktown aquifer, Pungo River aquifer, Castle Hayne aquifer, Beaufort aquifer, Peedee aquifer, Black Creek aquifer, upper Cape Fear aquifer, lower Cape Fear aquifer, and the Lower Cretaceous aquifer. The uppermost aquifer (the surficial aquifer in most places) is a water-table aquifer and the bottom of the system is underlain by crystalline bedrock. The sedimentary deposits forming the aquifers are of Holocene to Cretaceous age and are composed mostly of sand with lesser amounts of gravel and limestone. Confining units between aquifers are composed primarily of clay and silt. The thickness of the aquifers ranges from zero along the Fall Line to more than 10,000 feet at Cape Hatteras. Prominent structural features are the increasing easterly homoclinal dip of the sediments and the Cape Fear arch, the axis of which trends in a southeast direction. The stratigraphic continuity is determined from correlations of 161 geophysical logs along with data from drillers' and geologists' logs. Aquifers were defined by means of these logs plus water-level and water-quality data and evidence of the continuity of pumping effects. Eighteen hydrogeologic sections depict the correlation of these aquifers throughout the Coastal Plain.

  13. Hydrogeologic framework of the North Carolina coastal plain

    USGS Publications Warehouse

    Winner, M.D.; Coble, R.W.

    1996-01-01

    The hydrogeologic framework of the North Carolina Coastal Plain aquifer system consists of 10 aquifers separated by 9 confining units. From top to bottom, the aquifers are the surficial aquifer, Yorktown aquifer, Pungo River aquifer, Castle Hayne aquifer, Beaufort aquifer, Peedee aquifer, Black Creek aquifer, upper Cape Fear aquifer, lower Cape Fear aquifer, and Lower Cretaceous aquifer. The uppermost aquifer (the surficial aquifer in most places) is a water-table aquifer, and the bottom of the system is underlain by crystalline bedrock. The sedimentary deposits forming the aquifers are of Holocene to Cretaceous age and are composed mostly of sand, with lesser amounts of gravel and limestone. The confining units between the aquifers are composed primarily of clay and silt. The thickness of the aquifers ranges from zero along the Fall Line to more than 10,000 feet at Cape Hatteras. Prominent structural features are the increasing easterly homoclinal dip of the sediments and the Cape Fear arch, the axis of which trends in a southeast direction. Stratigraphic continuity was determined from correlations of 161 geophysical logs along with data from drillers? and geologists? logs. Aquifers were defined by means of these logs as well as water-level and water-quality data and evidence of the continuity of pumping effects. Eighteen hydrogeologic sections depict the correlation of these aquifers throughout the North Carolina Coastal Plain.

  14. Estimating canopy fuel parameters for Atlantic Coastal Plain forest types.

    SciTech Connect

    Parresol, Bernard, R.

    2007-01-15

    Abstract It is necessary to quantify forest canopy characteristics to assess crown fire hazard, prioritize treatment areas, and design treatments to reduce crown fire potential. A number of fire behavior models such as FARSITE, FIRETEC, and NEXUS require as input four particular canopy fuel parameters: 1) canopy cover, 2) stand height, 3) crown base height, and 4) canopy bulk density. These canopy characteristics must be mapped across the landscape at high spatial resolution to accurately simulate crown fire. Currently no models exist to forecast these four canopy parameters for forests of the Atlantic Coastal Plain, a region that supports millions of acres of loblolly, longleaf, and slash pine forests as well as pine-broadleaf forests and mixed species broadleaf forests. Many forest cover types are recognized, too many to efficiently model. For expediency, forests of the Savannah River Site are categorized as belonging to 1 of 7 broad forest type groups, based on composition: 1) loblolly pine, 2) longleaf pine, 3) slash pine, 4) pine-hardwood, 5) hardwood-pine, 6) hardwoods, and 7) cypress-tupelo. These 7 broad forest types typify forests of the Atlantic Coastal Plain region, from Maryland to Florida.

  15. The contribution of Alaskan, Siberian, and Canadian coastal polynas to the cold halocline layer of the Arctic Ocean

    NASA Technical Reports Server (NTRS)

    Cavalieri, Donald J.; Martin, Seelye

    1994-01-01

    Numerous Arctic Ocean circulation and geochemical studies suggest that ice growth in polynyas over the Alaskan, Siberian, and Canadian continental shelves is a source of cold, saline water which contributes to the maintenance of the Arctic Ocean halocline. The purpose of this study is to estimate for the 1978-1987 winters the contributions of Arctic coastal polynyas to the cold halocline layer of the Arctic Ocean. The study uses a combination of satellite, oceanographic, and weather data to calculate the brine fluxes from the polynyas; then an oceanic box model is used to calculate their contributions to the cold halocline layer of the Arctic Ocean. This study complements and corrects a previous study of dense water production by coastal polynyas in the Barents, Kara, and Laptev Seas.

  16. Data-driven models of groundwater salinization in coastal plains

    NASA Astrophysics Data System (ADS)

    Felisa, G.; Ciriello, V.; Antonellini, M.; Di Federico, V.; Tartakovsky, D. M.

    2015-12-01

    Salinization of shallow coastal aquifers is particularly critical for ecosystems and agricultural activities. Management of such aquifers is an open challenge, because predictive models, on which science-based decisions are to be made, often fail to capture the complexity of relevant natural and anthropogenic processes. Complicating matters further is the sparsity of hydrologic and geochemical data that are required to parameterize spatially distributed models of flow and transport. These limitations often undermine the veracity of modeling predictions and raise the question of their utility. As an alternative, we employ data-driven statistical approaches to investigate the underlying mechanisms of groundwater salinization in low coastal plains. A time-series analysis and auto-regressive moving average models allow us to establish dynamic relations between key hydrogeological variables of interest. The approach is applied to the data collected at the phreatic coastal aquifer of Ravenna, Italy. We show that, even in absence of long time series, this approach succeeds in capturing the behavior of this complex system, and provides the basis for making predictions and decisions.

  17. Geology, geochemistry, and tectonostratigraphic relations of the crystalline basement beneath the coastal plain of New Jersey and contiguous areas

    USGS Publications Warehouse

    Volkert, Richard A.; Drake, Avery Ala; Sugarman, Peter J.

    1996-01-01

    Coastal plain sediments are underlain by pre-Mesozoic crystalline rocks. The inner coastal plain is underlain by schist that is correlated with the Potomac Terrane, as well as by mafic rocks probably equivalent to the Wilmington or Bel Air-Rising Sun terranes. The northern and central outer coastal plain is underlain by metasedimentary rocks similar to the Brompton-Cameron Terrane. Rocks beneath the southern coastal plain probably correlate with those of the Chopawamsic and Roanoke Rapids terranes.

  18. Pesticides in Ground Water of the Maryland Coastal Plain

    USGS Publications Warehouse

    Denver, Judith M.; Ator, Scott W.

    2006-01-01

    Selected pesticides are detectable at low levels (generally less than 0.1 microgram per liter) in unconfined ground water in many parts of the Maryland Coastal Plain. Samples were recently collected (2001-04) from 47 wells in the Coastal Plain and analyzed for selected pesticides and degradate compounds (products of pesticide degradation). Most pesticide degradation occurs in the soil zone before infiltration to the water table, and degradates of selected pesticides were commonly detected in ground water, often at higher concentrations than their respective parent compounds. Pesticides and their degradates often occur in ground water in mixtures of multiple compounds, reflecting similar patterns in usage. All measured concentrations in ground water were below established standards for drinking water, and nearly all were below other health-based guidelines. Although drinking-water standards and guidelines are typically much higher than observed concentrations in ground water, they do not exist for many detected compounds (particularly degradates), or for mixtures of multiple compounds. The distribution of observed pesticide compounds reflects known usage patterns, as well as chemical properties and environmental factors that affect the fate and transport of these compounds in the environment. Many commonly used pesticides, such as glyphosate, pendimethalin, and 2,4-D were not detected in ground water, likely because they were sorbed onto organic matter or degraded in the soil zone. Others that are more soluble and (or) persistent, like atrazine, metolachlor, and several of their degradates, were commonly detected in ground water where they have been used. Atrazine, for example, an herbicide used primarily on corn, was most commonly detected in ground water on the Eastern Shore (where agriculture is common), particularly where soils are well drained. Conversely, dieldrin, an insecticide previously used heavily for termite control, was detected only on the Western

  19. Groundwater and microbial processes of Alabama coastal plain aquifers

    NASA Astrophysics Data System (ADS)

    Penny, Elizabeth; Lee, Ming-Kuo; Morton, Cynthia

    2003-11-01

    We integrate groundwater geochemistry, microbiology, and numerical modeling techniques to study the origin of elevated salinity and chemical evolution of groundwaters in the coastal plain aquifers of Alabama. Our field data indicate that chemical composition of groundwater evolves by various geochemical and microbial processes as it moves deeper into the subsurface. Sequential peaks of Ca2+, Mg2+, K+, and Na+ along flow paths indicate that separation of ions may be driven by cation exchange. Microbial-mediated reactions are important for the formation of several discrete hydrochemical zones containing Fe2+, Mn2+, Sr2+, and SO42- rich groundwaters. Elevated Fe2+, Mn2+, and Sr2+ concentrations may be derived from bacterial iron and manganese reduction. High sulfate concentrations observed a short distance from the recharge may be partly explained by microbial sulfur oxidation and nitrate reduction (denitrification). The presence of denitrifying and sulfur-oxidizing bacteria in water further supports these reactions. Major ion compositions and δD and δ18O values are used to determine the source of salinity and the nature of mixing of different groundwaters. Three water types were identified; these include carbonate groundwater, brines associated with evaporites, and groundwater of meteoric origin. Groundwater age differences and flow velocities were calculated using the 36Cl/Cl ratios. Calculated groundwater flow velocities within the Eutaw and Tuscaloosa aquifers are about 0.20 m/yr and 0.15 m/yr, respectively. We modeled basin-scale hydrologic and solute transport processes in a cross section extending from the aquifer outcrops to the Gulf Coast. The modeling result shows that the buried Jurassic Louann Salt can significantly increase groundwater salinity in the overlying coastal plain aquifers by density-driven advection and hydrodynamic dispersion. The modeling results are consistent with Cl/Br ratios and O/H isotope signatures, which indicate that salinity of

  20. Sediment Retention Within Coastal Plain Bottomland Forested Wetlands

    NASA Astrophysics Data System (ADS)

    Ross, K. M.; Hupp, C. R.

    2002-12-01

    Coastal Plain forested wetlands are unique ecosystems where fluvial geomorphic processes control sediment retention and vegetation patterns, which are intimately connected to each other. Yet, these inter-disciplinary associations are typically lacking in traditional ecologic or geomorphic research within these ecosystems. Floodplain sedimentation rates and patterns, suspended sediment concentrations, substrate characteristics, vegetation and fluvial geomorphology were measured in field studies in eight 1-ha sites along three tributaries of the Chesapeake Bay to determine the dominant physical processes controlling deposition, substrate, and vegetation patterns in forested wetlands. Annual deposition was measured at 104 locations with feldspar clay pads. Sedimentation rates across the floodplain sites are highly variable, ranging from 0.5 mm/yr to 26.6 mm/yr. Multiple regression analyses suggest that the spatial patterns in net-annual and long-term deposition and substrate properties (grain sizes, sand:clay, and sorting) are controlled by the frequency and duration of inundation events and the total number of inundated days per year, the manner that sediment is distributed through the floodplain (dominant flow paths and/or the presence of slough networks, for example), and the potential for deposition of suspended sediments. Similarly, floodplain community diversity is significantly related to fluvial geomorphic processes (annual net deposition rates, percent inundation per year, and inundation duration per event). The results of this study provide valuable information on the development and evolution of Coastal Plain floodplains in the context of vegetation diversity patterns that have significant implications for the restoration and conservation of these systems.

  1. Mid Pliocene sea levels along the southeast US coastal plain

    NASA Astrophysics Data System (ADS)

    Rovere, A.; Hearty, P. J.; Raymo, M. E.; Mitrovica, J. X.; Inglis, J.

    2012-12-01

    Proxy data suggest that during the Mid-Pliocene Warm Period (MPWP) atmospheric CO2 levels were roughly similar to today (between 350 and 450 ppmv) and that global average temperature was elevated by as much as 3°C with respect to preindustrial values. Estimates of sea level (SL) during the MPWP range from +10 m to >+40 m relative to present, reflecting uncertainties in our knowledge of the sensitivity to modest climate warming of the East Antarctic, West Antarctic and Greenland Ice Sheets. A primary objective of the PLIOMAX project (www.pliomax.org) is to combine models of paleosea-level signals with geological observations to significantly improve constraints on eustatic sea level during the MPWP. In this regard, the southeast US coastal plain is of strategic importance in MPWP sea level studies (Dowsett and Cronin, Geology, 1990). In fact, it is one of the few places where predicted glacio-isostatic effects are expected to exhibit a significant geographic variation (in this case, north-to-south). The coastal plain may also be influenced by dynamic topography driven by mantle convective flow. In this area, two factors drive the up-to-the-west dynamic tilting of the coast. The first is the descent of the Farallon slab, now located under the mid-part of the North American continent. The other is upwelling return flow under the east coast (Moucha et al., Earth Planet. Sci. Lett., 2008). That is, over the last few million years, dynamic topography is responsible for potentially tens of meters of uplift (sea-level fall) of the Pliocene shoreline along the southeast US coastal plain. We have mapped an almost continuous MPWP shoreline cut into Miocene and older formations. However, as a result of multiple inter-state investigations extending over the last century, both the geomorphic escarpment and the associated deposits have been named differently across the region. In Virginia, the Chippenham Thornburg scarp is associated with the Moore House formation; in North and

  2. Stratigraphy of Glen Rose Formation, Gulf coastal plain

    SciTech Connect

    Pittman, J.G. )

    1989-09-01

    Strata of the Glen Rose Formation and equivalent units crop out in a continuous band across the Edwards Plateau, the area of outcrop skirting the Llano uplift, the Lampasas cut plain, north-central Texas, southeastern Oklahoma, and southwestern Arkansas. These rocks dip into the subsurface of the Gulf coastal plain. Although the Glen Rose interval has been studied on outcrop and in the subsurface in these areas through numerous investigations of local scale and several regional review papers, a synthesis integrating subsurface with outcrop across the broad region and a more detailed lithostratigraphic framework are needed. On outcrop on the Edwards Plateau, the Glen Rose is divided into upper and lower members by the Corbula bed, a thin but widespread accumulation of the minute clam Carycorbula matinae. In this region, the Corbula bed lies beneath anhydrite and gypsum beds (dissolution zones on outcrop), which may be traced through laterally equivalent limestones in the subsurface around the Llano uplift to thin anhydrite stringers above the Ferry Lake Anhydrite in northeastern Texas. These stringers may be traced to the lower part of the Thorp Springs Member of the Glen Rose din the subsurface and outcrop area of north-central Texas. In the Paluxy River Valley, the Corbula bed occurs beneath the Thorp Springs. This specific correlation allows clear demarcation between beds of the upper and lower Glen Rose members in the region. Correlation of this type within the Glen Rose interval allows a detailed understanding of the depositional history of this sequence and provides a more explicitly defined lithostratigraphic framework into which future studies may be integrated.

  3. Effects of Concrete Channels on Stream Biogeochemistry, Maryland Coastal Plain

    NASA Astrophysics Data System (ADS)

    Prestegaard, K. L.; Gilbert, L.; Phemister, K.

    2005-05-01

    In the 1950's and 60's, extensive networks of cement-lined channels were built in suburban watersheds near Washington, D.C. to convey storm water to downstream locations. These cement-lined stream channels limit interactions between surface and groundwater and they provide sources of alkalinity in Maryland Coastal Plain watersheds that normally have low alkalinity. This project was designed to 1) compare base flow water chemistry in headwater reaches of urban and non-urban streams, and 2) to evaluate downstream changes in water chemistry in channelized urban streams in comparison with non-urban reference streams. During a drought year, headwater streams in both urban and non-urban sites had significant concentrations of Fe(II) that were discharged from groundwater sources and rapidly oxidized by iron-oxidizing bacteria. During a wet year, the concentrations of Fe(II) were higher in headwater urban streams than in the non-urban streams. This suggests that impervious surfaces in headwater urban watersheds prevent the recharge of oxygen-rich waters during storm events, which maintains iron-rich groundwater discharge to the stream. Downstream changes in water chemistry are prominent in cement-lined urban channels because they are associated with distinctive microbial communities. The headwater zones of channelized streams are dominated by iron-ozidizing bacteria, that are replaced downstream by manganese-oxidizing zones, and replaced further downstream by biofilms dominated by photosynthesizing cyanobacteria. The reaches dominated by cyanobacteria exhibit diurnal changes in pH due to uptake of CO2 for photosynthesis. Diurnal changes range from 7.5 to 8.8 in the summer months to 7.0 to 7.5 in the cooler months, indicating both the impact of photosynthesis and the additional source of alkalinity provided by concrete. The dissolved oxygen, pH, and other characteristics of tributaries dominated by cyanobacteria are similar to the water chemistry characteristics observed in

  4. THE EFFECTS OF RIPARIAN MANAGEMENT ON DETRITUS PROCESSING AND INVERTEBRATE ASSEMBLAGES IN COASTAL PLAIN INTERMITTENT STREAMS

    EPA Science Inventory

    Silviculture is the primary land use within many Coastal Plain watersheds of the southeastern United States, where most forested wetlands are found along headwater intermittent streams. Our study compared invertebrate assemblages and breakdown of buried detritus (leaves, wood, a...

  5. Invertebrate colonization of leaves and roots within sediments of intermittent coastal plain streams across hydrologic phases

    EPA Science Inventory

    We compared benthic invertebrate assemblages colonizing three types of buried substrates (leaves, roots and plastic roots) among three intermittent Coastal Plain streams over a one year period. Invertebrate density was significantly lower in root litterbags than in plastic root l...

  6. Mercury dynamics in a coastal plain watershed: insights from multiple models and empirical data

    EPA Science Inventory

    Interactions among atmospherically deposited mercury, abundant wetlands, and surface waters with elevated acidity and dissolved organic carbon (DOC) often lead to widespread mercury-related fish consumption advisories in the Coastal Plain of the southeastern United States (US). H...

  7. Savannah River Region: Transition between the Gulf and Atlantic Coastal Plains. Proceedings

    SciTech Connect

    Zullo, V.A.; Harris, W.B.; Price, V.

    1990-12-31

    The focus of the this conference of Coastal Plains geologists was on the Savannah River region of Georgia and South Carolina, and particularly on the geology of the US Department of Energy`s 300 square mile Savannah River Site (SRS) in western South Carolina. Current geological studies indicate that the Mesozoic-Cenozoic section in the Savannah River region is transitional between that of the Gulf Coastal Plain to the southwest and that of the Atlantic Coastal Plain to the northeast. With the transitional aspect of the region as its theme, the first session was devoted to overviews of Cretaceous and Paleogene geology in the Gulf and Atlantic Coastal Plains. Succeeding presentations and resulting discussions dealt with more specific problems in structural, lithostratigraphic, hydrological, biostratigraphic, and cyclostratigraphic analysis, and of correlation to standard stratigraphic frameworks. For these conference proceedings, individual papers have been processed separately for the Energy Data Base.

  8. Groundwater discharge along a channelized Coastal Plain stream

    USGS Publications Warehouse

    LaSage, D.M.; Sexton, J.L.; Mukherjee, A.; Fryar, A.E.; Greb, S.F.

    2008-01-01

    In the Coastal Plain of the southeastern USA, streams have commonly been artificially channelized for flood control and agricultural drainage. However, groundwater discharge along such streams has received relatively little attention. Using a combination of stream- and spring-flow measurements, spring temperature measurements, temperature profiling along the stream-bed, and geologic mapping, we delineated zones of diffuse and focused discharge along Little Bayou Creek, a channelized, first-order perennial stream in western Kentucky. Seasonal variability in groundwater discharge mimics hydraulic-head fluctuations in a nearby monitoring well and spring-discharge fluctuations elsewhere in the region, and is likely to reflect seasonal variability in recharge. Diffuse discharge occurs where the stream is incised into the semi-confined regional gravel aquifer, which is comprised of the Mounds Gravel. Focused discharge occurs upstream where the channel appears to have intersected preferential pathways within the confining unit. Seasonal fluctuations in discharge from individual springs are repressed where piping results in bank collapse. Thereby, focused discharge can contribute to the morphological evolution of the stream channel. ?? 2008 Elsevier B.V. All rights reserved.

  9. Shallow Groundwater Mercury Supply in a Coastal Plain Stream

    PubMed Central

    2012-01-01

    Fluvial methylmercury (MeHg) is attributed to methylation in up-gradient wetland areas. This hypothesis depends on efficient wetland-to-stream hydraulic transport under nonflood and flood conditions. Fluxes of water and dissolved (filtered) mercury (Hg) species (FMeHg and total Hg (FTHg)) were quantified in April and July of 2009 in a reach at McTier Creek, South Carolina to determine the relative importance of tributary surface water and shallow groundwater Hg transport from wetland/floodplain areas to the stream under nonflood conditions. The reach represented less than 6% of upstream main-channel distance and 2% of upstream basin area. Surface-water discharge increased within the reach by approximately 10%. Mean FMeHg and FTHg fluxes increased within the reach by 23–27% and 9–15%, respectively. Mass balances indicated that, under nonflood conditions, the primary supply of water, FMeHg, and FTHg within the reach (excluding upstream surface water influx) was groundwater discharge, rather than tributary transport from wetlands, in-stream MeHg production, or atmospheric Hg deposition. These results illustrate the importance of riparian wetland/floodplain areas as sources of fluvial MeHg and of groundwater Hg transport as a fundamental control on Hg supply to Coastal Plain streams. PMID:22734594

  10. Groundwater Discharge along a Channelized Coastal Plain Stream

    SciTech Connect

    LaSage, Danita M; Sexton, Joshua L; Mukherjee, Abhijit; Fryar, Alan E; Greb, Stephen F

    2015-10-01

    In the Coastal Plain of the southeastern USA, streams have commonly been artificially channelized for flood control and agricultural drainage. However, groundwater discharge along such streams has received relatively little attention. Using a combination of stream- and spring-flow measurements, spring temperature measurements, temperature profiling along the stream-bed, and geologic mapping, we delineated zones of diffuse and focused discharge along Little Bayou Creek, a channelized, first-order perennial stream in western Kentucky. Seasonal variability in groundwater discharge mimics hydraulic-head fluctuations in a nearby monitoring well and spring-discharge fluctuations elsewhere in the region, and is likely to reflect seasonal variability in recharge. Diffuse discharge occurs where the stream is incised into the semi-confined regional gravel aquifer, which is comprised of the Mounds Gravel. Focused discharge occurs upstream where the channel appears to have intersected preferential pathways within the confining unit. Seasonal fluctuations in discharge from individual springs are repressed where piping results in bank collapse. Thereby, focused discharge can contribute to the morphological evolution of the stream channel.

  11. Shallow groundwater mercury supply in a coastal plain stream

    USGS Publications Warehouse

    Bradley, Paul M.; Journey, Celeste A.; Lowery, Mark A.; Brigham, Mark E.; Burns, Douglas A.; Button, Daniel T.; Chapelle, Francis H.; Lutz, Michelle A.; Marvin-DiPasquale, Mark C.; Riva-Murray, Karen

    2012-01-01

    Fluvial methylmercury (MeHg) is attributed to methylation in up-gradient wetland areas. This hypothesis depends on efficient wetland-to-stream hydraulic transport under nonflood and flood conditions. Fluxes of water and dissolved (filtered) mercury (Hg) species (FMeHg and total Hg (FTHg)) were quantified in April and July of 2009 in a reach at McTier Creek, South Carolina to determine the relative importance of tributary surface water and shallow groundwater Hg transport from wetland/floodplain areas to the stream under nonflood conditions. The reach represented less than 6% of upstream main-channel distance and 2% of upstream basin area. Surface-water discharge increased within the reach by approximately 10%. Mean FMeHg and FTHg fluxes increased within the reach by 23–27% and 9–15%, respectively. Mass balances indicated that, under nonflood conditions, the primary supply of water, FMeHg, and FTHg within the reach (excluding upstream surface water influx) was groundwater discharge, rather than tributary transport from wetlands, in-stream MeHg production, or atmospheric Hg deposition. These results illustrate the importance of riparian wetland/floodplain areas as sources of fluvial MeHg and of groundwater Hg transport as a fundamental control on Hg supply to Coastal Plain streams.

  12. Dissolved phosphorus retention and release from southeastern USA Coastal Plain in-stream wetlands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the southeastern USA Coastal Plain region, many inland surface water systems will meander through flat or depressional landscape areas prior to discharge into coastal estuaries. Slow water flow through these areas often causes flooding that promotes formation of in-stream wetlands with dense vege...

  13. A Surficial Hydrogeologic Framework for the Mid-Atlantic Coastal Plain

    USGS Publications Warehouse

    Ator, Scott W.; Denver, Judith M.; Krantz, David E.; Newell, Wayne L.; Martucci, Sarah K.

    2005-01-01

    A surficial hydrogeologic framework was developed for the Mid-Atlantic Coastal Plain, from New Jersey through North Carolina. The framework includes seven distinct hydrogeologic subregions within which the primary natural physical factors affecting the flow and chemistry of shallow ground water and small streams are relatively consistent. Within most subregions, the transport of chemicals from the land surface to ground water and streams can be described by a fairly uniform set of natural processes; some subregions include mixed hydrogeologic settings that are indistinguishable at the regional scale. The hydrogeologic framework and accompanying physiographic and geologic delineations are presented in digital and printed format. The seven hydrogeologic subregions that constitute the framework were delineated primarily on the basis of physiography and the predominant texture (typical grain size) of surficial and (where surficial sediments are particularly thin) subcropping sediments. Physiography for the Mid-Atlantic Coastal Plain was constructed by standardizing and extrapolating previously published interpretations for the Coastal Plain of South Carolina and New Jersey, based on similar work in the other States. Surficial and subcropping geology were similarly compiled from previous publications by resolving inconsistencies in nomenclature, interpretation, and scale, and interpolating across unmapped areas. A bulk sediment texture was determined for each mapped geologic unit on the basis of published descriptions. Fundamental differences among the seven hydrogeologic subregions are described on the basis of hypotheses about surficial and shallow subsurface hydrology and water chemistry in each, as well as variable land use, soils, and topography. On the regional scale, the Coastal Lowlands (Subregion 1), the Middle Coastal Plain Fine Sediments (Subregion 3), the Middle Coastal Plain Sands with Overlying Gravels (Subregion 4), and the Inner Coastal Plain Upland

  14. Glaciation of the Coastal Plain of Northern Alaska

    NASA Astrophysics Data System (ADS)

    Jorgenson, M. T.; Shur, Y.

    2008-12-01

    Our 15 years of studies of permafrost soils on the coastal plain of northern Alaska show that it was affected by a continental ice sheet during the last glacial maximum. Evidence for this includes: occurrence of buried glacial basal ice at Barter Island; widespread sandy diamicton from Demarcation Bay to Barrow of late Pleistocene age; orientation of surficial deposits; poorly integrated drainage and gentle ridge and swale topography; the continuity of glacial-related deposits from the coast to the Brooks Foothills; and perennially frozen sediments unlike those of unglaciated Arctic regions. We documented a 10-m-high exposure ~1 km long at Barter Island that had abundant basal glacier ice with large-scale deformation structures, complex ice-contact deposits, and highly deformed bedded silt, sand, and gravel inclusions within the basal ice. Similar ice structures were observed at Prudhoe Bay and Cape Halkett. The glacial till is highly unusual in that it is comprised of massive, non-fossiliferous, brackish, slightly pebbly loamy sand with occasional gravel to cobble-sized clasts. In most areas the till is only 2-5 m thick, although at Barter Island the till was up to 10- m thick. Gravel particles, which comprise 1-5% of the deposits, usually are 0.5-2 cm long, mostly durable chert, highly polished, and frequently cracked off at one end, with the broken face faceted and polished. We believe the material mostly originated from marine deposits on the continental shelf, although rocks of Canadian provenance also occur. Prevalent, large (1-5 m) deformation features of discontinuous yellow oxidized and gray reduced sediment suggest deformation of sediment during collapse of the ice sheet. The sandy till is found along most of the Beaufort coast with the exception of deltas and lagoons and is found inland as much as 80 km. The sandy till is easily eroded, causing the morainal margin to be indistinct and the topography subdued. Previous thermoluminescence dating by

  15. SRTM Perspective View with Landsat Overlay: Costa Rica Coastal Plain

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This perspective view shows the northern coastal plain of Costa Rica with the Cordillera Central, composed of a number of active and dormant volcanoes, rising in the background. This view looks toward the south over the Rio San Juan, which marks the boundary between Costa Rica and Nicaragua. The smaller river joining Rio San Juan in the center of the image is Rio Sarapiqui, which is navigable upstream as far inland as Puerto Viejo (Old Port) de Sarapiqui at the mountain's base. This river was an important transportation route for those few hardy settlers who first moved into this region, although as recently as 1953 a mere three thatched-roof houses were all that comprised the village of Puerto Viejo.

    This coastal plain is a sedimentary basin formed about 50 million years ago composed of river alluvium and lahar (mud and ash flow) deposits from the volcanoes of the Cordillera Central. It comprises the province of Heredia (the smallest of Costa Rica's seven) and demonstrates a wide range of climatic conditions, from warm and humid lowlands to cool and damp highlands, and including the mild but seasonally wet and dry Central Valley.

    This image was generated in support of the Central American Commission for Environment and Development through an agreement with NASA. The Commission involves eight nations working to develop the Mesoamerican Biological Corridor, an effort to study and preserve some of the most biologically diverse regions of the planet.

    This three-dimensional perspective view was generated using topographic data from the Shuttle Radar Topography Mission (SRTM) and an enhanced false-color Landsat 7 satellite image. Colors are from Landsat bands 5, 4, and 2 as red, green and blue, respectively. Topographic expression is exaggerated 2X.

    Landsat has been providing visible and infrared views of the Earth since 1972. SRTM elevation data matches the 30-meter resolution of most Landsat images and will substantially help in analyses of the large

  16. Biological integrity in mid-atlantic coastal plains headwater streams.

    PubMed

    Megan, Mehaffey H; Nash, Maliha S; Neale, Anne C; Pitchford, Ann M

    2007-01-01

    The objective of this study was to assess the applicability of using landscape variables in conjunction with water quality and benthic data to efficiently estimate stream condition of select headwater streams in the Mid-Atlantic Coastal Plains. Eighty-two streams with riffle sites were selected from eight-two independent watersheds across the region for sampling and analyses. Clustering of the watersheds by landscape resulted in three distinct groups (forest, crop, and urban) which coincided with watersheds dominant land cover or use. We used non-parametric analyses to test differences in benthos and water chemistry between groups, and used regression analyses to evaluate responses of benthic communities to water chemistry within each of the landscape groups. We found that typical water chemistry measures associated with urban runoff such as specific conductance and dissolved chloride were significantly higher in the urban group. In the crop group, we found variables commonly associated with farming such as nutrients and pesticides significantly greater than in the other two groups. Regression analyses demonstrated that the numbers of tolerant and facultative macroinvertebrates increased significantly in forested watersheds with small shifts in pollutants, while in human use dominated watersheds the intolerant macroinvertebrates were more sensitive to shifts in chemicals present at lower concentrations. The results from this study suggest that landscape based clustering can be used to link upstream landscape characteristics, water chemistry and biotic integrity in order to assess stream condition and likely cause of degradation without the use of reference sites. Notice: Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

  17. Localized sulfate-reducing zones in a coastal plain aquifer

    USGS Publications Warehouse

    Brown, C.J.; Coates, J.D.; Schoonen, M.A.A.

    1999-01-01

    High concentrations of dissolved iron in ground water of coastal plain or alluvial aquifers contribute to the biofouling of public supply wells for which treatment and remediation is costly. Many of these aquifers, however, contain zones in which microbial sulfate reduction and the associated precipitation of iron-sulfide minerals decreases iron mobility. The principal water-bearing aquifer (Magothy Aquifer of Cretaceous age) in Suffolk County, New York, contains localized sulfate-reducing zones in and near lignite deposits, which generally are associated with clay lenses. Microbial analyses of core samples amended with [14C]-acetate indicate that microbial sulfate reduction is the predominant terminal-electron-accepting process (TEAP) in poorly permeable, lignite-rich sediments at shallow depths and near the ground water divide. The sulfate-reducing zones are characterized by abundant lignite and iron-sulfide minerals, low concentrations of Fe(III) oxyhydroxides, and by proximity to clay lenses that contain pore water with relatively high concentrations of sulfate and dissolved organic carbon. The low permeability of these zones and, hence, the long residence time of ground water within them, permit the preservation and (or) allow the formation of iron-sulfide minerals, including pyrite and marcasite. Both sulfate-reducing bacteria (SRB) and iron-reducing bacteria (IRB) are present beneath and beyond the shallow sulfate-reducing zones. A unique Fe(III)-reducing organism, MD-612, was found in core sediments from a depth of 187 m near the southern shore of Long Island. The distribution of poorly permeable, lignite-rich, sulfate-reducing zones with decreased iron concentration is varied within the principal aquifer and accounts for the observed distribution of dissolved sulfate, iron, and iron sulfides in the aquifer. Locating such zones for the placement of production wells would be difficult, however, because these zones are of limited aerial extent.

  18. Rates of Microbial Metabolism in Deep Coastal Plain Aquifers

    PubMed Central

    Chapelle, Francis H.; Lovley, Derek R.

    1990-01-01

    Rates of microbial metabolism in deep anaerobic aquifers of the Atlantic coastal plain of South Carolina were investigated by both microbiological and geochemical techniques. Rates of [2-14C]acetate and [U-14C]glucose oxidation as well as geochemical evidence indicated that metabolic rates were faster in the sandy sediments composing the aquifers than in the clayey sediments of the confining layers. In the sandy aquifer sediments, estimates of the rates of CO2 production (millimoles of CO2 per liter per year) based on the oxidation of [2-14C] acetate were 9.4 × 10−3 to 2.4 × 10−1 for the Black Creek aquifer, 1.1 × 10−2 for the Middendorf aquifer, and <7 × 10−5 for the Cape Fear aquifer. These estimates were at least 2 orders of magnitude lower than previously published estimates that were based on the accumulation of CO2 in laboratory incubations of similar deep subsurface sediments. In contrast, geochemical modeling of groundwater chemistry changes along aquifer flowpaths gave rate estimates that ranged from 10−4 to 10−6 mmol of CO2 per liter per year. The age of these sediments (ca. 80 million years) and their organic carbon content suggest that average rates of CO2 production could have been no more than 10−4 mmol per liter per year. Thus, laboratory incubations may greatly overestimate the in situ rates of microbial metabolism in deep subsurface environments. This has important implications for the use of laboratory incubations in attempts to estimate biorestoration capacities of deep aquifers. The rate estimates from geochemical modeling indicate that deep aquifers are among the most oligotrophic aquatic environments in which there is ongoing microbial metabolism. PMID:16348227

  19. Rates of microbial metabolism in deep coastal plain aquifers

    SciTech Connect

    Chapelle, F.H. ); Lovley, D.R. )

    1990-06-01

    Rates of microbial metabolism in deep anaerobic aquifers of the Atlantic coastal plain of South Carolina were investigated by both microbiological and geochemical techniques. Rates of (2-{sup 14}C)acetate and (U-{sup 14}C)glucose oxidation as well as geochemical evidence indicated that metabolic rates were faster in the sandy sediments composing the aquifers than in the clayey sediments of the confirming layers. In the many aquifer sediments, estimates of the rates of CO{sub 2} production (millimoles of CO{sub 2} per liter per year) based on the oxidation of (2-{sup 14}C) acetate were 9.4 {times} 10{sup {minus}3} to 2.4 {times} 10{sup {minus}1} for the Black Creek aquifer, 1.1 {times} 10{sup {minus}2} for the Middendorf aquifer, and < 7 {times} 10{sup {minus}5} for the Cape Fear aquifer. These estimates were at least 2 orders of magnitude lower than previously published estimates that were based on the accumulation of CO{sub 2} in laboratory incubations of similar deep subsurface sediments. In contrast, geochemical modeling of groundwater chemistry changes along aquifer flowpaths gave rate estimates that ranged from 10{sup {minus}4} to 10{sup {minus}6} mmol of CO{sub 2} production could have been no more than 10{sup {minus}4} mmol per liter per year. Thus, laboratory incubations may greatly overestimate the in situ rates of microbial metabolism in deep subsurface environments. This has important implications for the use of laboratory incubations in attempts to estimate biorestoration capacities of deep aquifers. The rate estimates from geochemical modeling indicate that deep aquifers are among the most oligotrophic aquatic environments in which there is ongoing microbial metabolism.

  20. Rates of microbial metabolism in deep coastal plain aquifers

    USGS Publications Warehouse

    Chapelle, F.H.; Lovley, D.R.

    1990-01-01

    Rates of microbial metabolism in deep anaerobic aquifers of the Atlantic coastal plain of South Carolina were investigated by both microbiological and geochemical techniques. Rates of [2-14C]acetate and [U-14C]glucose oxidation as well as geochemical evidence indicated that metabolic rates were faster in the sandy sediments composing the aquifers than in the clayey sediments of the confining layers. In the sandy aquifer sediments, estimates of the rates of CO2 production (millimoles of CO2 per liter per year) based on the oxidation of [2-14C]acetate were 9.4 x 10-3 to 2.4 x 10-1 for the Black Creek aquifer, 1.1 x 10-2 for the Middendorf aquifer, and <7 x 10-5 for the Cape Fear aquifer. These estimates were at least 2 orders of magnitude lower than previously published estimates that were based on the accumulation of CO2 in laboratory incubations of similar deep subsurface sediments. In contrast, geochemical modeling of groundwater chemistry changes along aquifer flowpaths gave rate estimates that ranged from 10-4 to 10-6 mmol of CO2 per liter per year. The age of these sediments (ca. 80 million years) and their organic carbon content suggest that average rates of CO2 production could have been no more than 10-4 mmol per liter per year. Thus, laboratory incubations may greatly overestimate the in situ rates of microbial metabolism in deep subsurface environments. This has important implications for the use of laboratory incubations in attempts to estimate biorestoration capacities of deep aquifers. The rate estimates from geochemical modeling indicate that deep aquifers are among the most oligotrophic aquatic environments in which there is ongoing microbial metabolism.

  1. All-weather ice information system for Alaskan arctic coastal shipping

    NASA Technical Reports Server (NTRS)

    Gedney, R. T.; Jirberg, R. J.; Schertler, R. J.; Mueller, R. A.; Chase, T. L.; Kramarchuk, I.; Nagy, L. A.; Hanlon, R. A.; Mark, H.

    1977-01-01

    A near real-time ice information system designed to aid arctic coast shipping along the Alaskan North Slope is described. The system utilizes a X-band Side Looking Airborne Radar (SLAR) mounted aboard a U.S. Coast Guard HC-130B aircraft. Radar mapping procedures showing the type, areal distribution and concentration of ice cover were developed. In order to guide vessel operational movements, near real-time SLAR image data were transmitted directly from the SLAR aircraft to Barrow, Alaska and the U.S. Coast Guard icebreaker Glacier. In addition, SLAR image data were transmitted in real time to Cleveland, Ohio via the NOAA-GOES Satellite. Radar images developed in Cleveland were subsequently facsimile transmitted to the U.S. Navy's Fleet Weather Facility in Suitland, Maryland for use in ice forecasting and also as a demonstration back to Barrow via the Communications Technology Satellite.

  2. Hydrogeomorphic processes of thermokarst lakes with grounded-ice and floating-ice regimes on the Arctic coastal plain, Alaska

    USGS Publications Warehouse

    Arp, C.D.; Jones, Benjamin M.; Urban, F.E.; Grosse, G.

    2011-01-01

    Thermokarst lakes cover > 20% of the landscape throughout much of the Alaskan Arctic Coastal Plain (ACP) with shallow lakes freezing solid (grounded ice) and deeper lakes maintaining perennial liquid water (floating ice). Thus, lake depth relative to maximum ice thickness (1·5–2·0 m) represents an important threshold that impacts permafrost, aquatic habitat, and potentially geomorphic and hydrologic behaviour. We studied coupled hydrogeomorphic processes of 13 lakes representing a depth gradient across this threshold of maximum ice thickness by analysing remotely sensed, water quality, and climatic data over a 35-year period. Shoreline erosion rates due to permafrost degradation ranged from L) with periods of full and nearly dry basins. Shorter-term (2004–2008) specific conductance data indicated a drying pattern across lakes of all depths consistent with the long-term record for only shallow lakes. Our analysis suggests that grounded-ice lakes are ice-free on average 37 days longer than floating-ice lakes resulting in a longer period of evaporative loss and more frequent negative P − EL. These results suggest divergent hydrogeomorphic responses to a changing Arctic climate depending on the threshold created by water depth relative to maximum ice thickness in ACP lakes.

  3. Modeling of Dense Water Production and Salt Transport from Alaskan Coastal Polynyas

    NASA Technical Reports Server (NTRS)

    Signorini, Sergio R.; Cavalieri, Donald J.

    2000-01-01

    The main significance of this paper is that a realistic, three-dimensional, high-resolution primitive equation model has been developed to study the effects of dense water formation in Arctic coastal polynyas. The model includes realistic ambient stratification, realistic bottom topography, and is forced by time-variant surface heat flux, surface salt flux, and time-dependent coastal flow. The salt and heat fluxes, and the surface ice drift, are derived from satellite observations (SSM/I and NSCAT sensors). The model is used to study the stratification, salt transport, and circulation in the vicinity of Barrow Canyon during the 1996/97 winter season. The coastal flow (Alaska coastal current), which is an extension of the Bering Sea throughflow, is formulated in the model using the wind-transport regression. The results show that for the 1996/97 winter the northeastward coastal current exports 13% to 26% of the salt produced by coastal polynyas upstream of Barrow Canyon in 20 to 30 days. The salt export occurs more rapidly during less persistent polynyas. The inclusion of ice-water stress in the model makes the coastal current slightly weaker and much wider due to the combined effects of surface drag and offshore Ekman transport.

  4. Geologic Map of the Santa Barbara Coastal Plain Area, Santa Barbara County, California

    USGS Publications Warehouse

    Minor, Scott A.; Kellogg, Karl S.; Stanley, Richard G.; Gurrola, Larry D.; Keller, Edward A.; Brandt, Theodore R.

    2009-01-01

    This report presents a newly revised and expanded digital geologic map of the Santa Barbara coastal plain area at a compilation scale of 1:24,000 (one inch on the map to 2,000 feet on the ground)1 and with a horizontal positional accuracy of at least 20 m. The map depicts the distribution of bedrock units and surficial deposits and associated deformation underlying and adjacent to the coastal plain within the contiguous Dos Pueblos Canyon, Goleta, Santa Barbara, and Carpinteria 7.5' quadrangles. The new map supersedes an earlier preliminary geologic map of the central part of the coastal plain (Minor and others, 2002; revised 2006) that provided coastal coverage only within the Goleta and Santa Barbara quadrangles. In addition to new mapping to the west and east, geologic mapping in parts of the central map area has been significantly revised from the preliminary map compilation - especially north of downtown Santa Barbara in the Mission Ridge area - based on new structural interpretations supplemented by new biostratigraphic data. All surficial and bedrock map units, including several new units recognized in the areas of expanded mapping, are described in detail in the accompanying pamphlet. Abundant new biostratigraphic and biochronologic data based on microfossil identifications are presented in expanded unit descriptions of the marine Neogene Monterey and Sisquoc Formations. Site-specific fault kinematic observations embedded in the digital map database are more complete owing to the addition of slip-sense determinations. Finally, the pamphlet accompanying the present report includes an expanded and refined summary of stratigraphic and structural observations and interpretations that are based on the composite geologic data contained in the new map compilation. The Santa Barbara coastal plain is located in the western Transverse Ranges physiographic province along an east-west-trending segment of the southern California coastline about 100 km (62 mi) northwest

  5. Contrasting soils and landscapes of the Piedmont and Coastal Plain, eastern United States

    USGS Publications Warehouse

    Markewich, H.W.; Pavich, M.J.; Buell, G.R.

    1990-01-01

    The Piedmont and Coastal Plain physiographic provinces comprise 80 percent of the Atlantic Coastal states from New Jersey to Georgia. The provinces are climatically similar. The soil moisture regime is udic. The soil temperature regime is typically thermic from Virginia through Georgia, although it is mesic at altitudes above 400 m in Georgia and above 320 m in Virginia. The soil temperature regime is mesic for the Piedmont and Coastal Plain from Maryland through New Jersey. The tightly folded, structurally complex crystalline rocks of the Piedmont and the gently dipping "layer-cake" clastic sedimentary rocks and sediments of the Coastal Plain respond differently to weathering, pedogenesis, and erosion. The different responses result in two physiographically contrasting terrains; each has distinctive near-surface hydrology, regolith, drainage morphology, and morphometry. The Piedmont is predominantly an erosional terrain. Interfluves are as narrow as 0.5 to 2 km, and are convex upward. Valleys are as narrow as 0.1 to 0.5 km and generally V-shaped in cross section. Alluvial terraces are rare and discontinuous. Soils in the Piedmont are typically less than 1 m thick, have less sand and more clay than Coastal Plain soils, and generally have not developed sandy epipedons. Infiltration rates for Piedmont soils are low at 6-15 cm/h. The soil/saprolite, soil/rock, and saprolite/rock boundaries are distinct (can be placed within 10 cm) and are characterized by ponding and/or lateral movement of water. Water movement through soil into saprolite, and from saprolite into rock, is along joints, foliation, bedding planes and faults. Soils and isotopic data indicate residence times consistent with a Pleistocene age for most Piedmont soils. The Coastal Plain is both an erosional and a constructional terrain. Interfluves commonly are broader than 2 km and are flat. Valleys are commonly as wide as 1 km to greater than 10 km, and contain numerous alluvial and estuarine terrace

  6. Episodic acidification of a coastal plain stream in Virginia

    USGS Publications Warehouse

    O'Brien, A. K.; Eshleman, K.N.

    1996-01-01

    This study investigates the episodic acidification of Reedy Creek, a wetland-influenced coastal plain stream near Richmond, Virginia. Primary objectives of the study were to quantify the episodic variability of acid- base chemistry in Reedy Creek, to examine the seasonal variability in episodic response and to explain the hydrological and geochemical factors that contribute to episodic acidification. Chemical response was similar in each of the seven storms examined, however, the ranges in concentrations observed were commonly greater in summer/fall storms than in winter/spring storms. An increase in SO4/2- concentration with discharge was observed during all storms and peak concentration occurred at or near peak flow. Small increases in Mg2+, Ca2+, K+ concentrations and dissolved organic carbon (DOC) were observed during most storms. At the same time, ANC, Na+ and Cl- concentrations usually decreased with increasing discharge. In summer/fall storms, the absolute increase in SO4/2- concentration was one-third to 15 times the increase observed in winter/spring storms; the decrease in ANC during summer/fall storms was usually within the range of the decrease observed in winter/spring storms. In contrast, the decrease in Na+ and Cl- concentrations during winter/spring storms was much greater than that observed during summer/fall storms. Data show that while base flow anion deficit was higher in summer/fall than in winter/spring, anion deficit decreased during most summer/fall storms. In contrast, base flow anion deficit was lower in spring and winter, but increased during winter/spring storms. Increased SO4/2- concentration was the main cause of episodic acidification during storms at Reedy Creek, but increased anion deficit indicates organic acids may contribute to episodic acidification during winter/spring storms. Changes in SO4/2- concentration coincident with the hydrograph rise indicate quick routing of water through the watershed. Saturation overland flow

  7. Ground water contamination and costs of pesticide restrictions in the southeastern coastal plain

    SciTech Connect

    Danielson, L.E.; Carlson, G.A.; Liu, S.; Weber, J.B.; Warren, R.

    1993-01-01

    The project developed new methodology for estimating: (1) groundwater contamination potential (GWCP) in the Southeast Coastal Plain, and (2) the potential economic impacts of selected policies that restrict pesticide use. The potential for ground water contamination was estimated by use of a simple matrix for combining ratings for both soil leaching potential and pesticide leaching potential. Key soil variables included soil texture, soil acidity and organic matter content. Key pesticide characteristics included Koc, pesticide half-life, the rate of application and the fraction of the pesticide hitting the soil. Comparisons of pesticide use from various farmer and expert opinion surveys were made for pesticide groups and for individual pesticide products. Methodology for merging the GWCP changes and lost benefits from selected herbicide cancellations was developed using corn production in the North Carolina Coastal Plain. Economic evaluations of pesticide cancellations for corn included national and Coastal Plain estimates for atrazine; metolachlor; dicamba; dicamba and atrazine; and dicamba, atrazine and metolachlor.

  8. Prediction of episodic acidification in Maryland Coastal Plain streams. Final report

    SciTech Connect

    Gerritsen, J.; Dietz, J.; Wilson, H.T.; Janicki, A.J.

    1989-12-01

    Episodic acidification from acidic precipitation in Coastal Plain streams of the Chesapeake Bay watershed is a potential threat to spawning and survival of anadromous fish species. The study is part of a process of selection of streams for mitigation of acidic episodes to increase the spawning success of anadromous fish stocks. It describes the development of practical, empirical models to predict the chemical response of Coastal Plain streams during precipitation events. One of the design criteria for the models was that they predict the response of a stream to precipitation events using data that are relatively easy to obtain. Data used to build and test the models were from several intensive studies of episodic acidification in the Maryland Coastal Plain. Regression models were developed to predict minimum pH during an event, change in pH during an event and minimum ANC (alkalinity) during an event. Two models were developed for each dependent variable.

  9. Evaluation of stream chemistry and watershed characteristics in the mid-atlantic coastal plain

    SciTech Connect

    Janicki, A.; Morgan, M.; Lynch, J.

    1995-12-31

    The purpose of this study was to apply the stream classification model developed from Maryland Synoptic Stream Chemistry Study data base to assess the relative importance of acidic deposition and other anthropogenic disturbances on acidity in Mid-Atlantic Coastal Plain streams. Data pertaining to Mid-Atlantic Coastal Plain watershed geology, soils, land use type, and stream chemistry were obtained from USEPA National Stream Survey, USGS and County Soil Conservation Services from New Jersey to North Carolina. These data were used in a regression analysis to establish the relative importance of ions determining stream water acidity. The study results support the conclusion that acidic deposition has substantially altered the acid base chemistry of Mid-Atlantic Coastal Plain Streams.

  10. Modeling dense water production and salt transport from Alaskan coastal polynyas

    NASA Astrophysics Data System (ADS)

    Signorini, Sergio R.; Cavalieri, Donald J.

    2002-09-01

    A three-dimensional primitive equation model was used to assess the effects of dense water formation from winter (1996/1997) polynyas on the ambient stratification, salt transport, and circulation in the vicinity of Barrow Canyon. The model, which includes ambient stratification and bottom topography, is forced by time-varying surface heat flux, surface salt flux, and coastal flow. The influence of sea ice drift on the circulation and salt transport is also analyzed by prescribing ice water stress at the sea surface. The surface fluxes and ice drift are derived from satellite observations (Special Sensor Microwave Imager (SSM/I) and NASA scatterometer (NSCAT) sensors). The coastal flow (Alaska coastal current), which is an extension of the Bering Sea throughflow, is formulated in the model by using a wind-transport regression. One set of experiments was forced by strong and persistent polynyas, simulated by 20-day averaged heat and salt fluxes originating from the largest events. In this set of experiments both strong and weak steady coastal currents were imposed. The amount of salt exported from the generation area depended on the strength of the current. Another set of experiments was forced by weaker and less persistent polynyas using time-varying forcing. The experiments with time-varying polynya forcing were conducted with two ambient vertical stratifications, one representing fall conditions and one representing winter conditions. The amount of salt retained on the shelf was found to be quite sensitive to the initial stratification. Weaker vertical stratification promotes a deeper mixed layer, which develops 20 times faster than the horizontal advective timescale of the coastal current, thus increasing the residence time of the salt generated by the polynya on the shelf. The time-varying northeastward coastal current, combined with the offshore Ekman transport, can export 29-73% of the salt produced by polynyas upstream of Barrow Canyon, depending upon the

  11. A new GIS approach for reconstructing and mapping dynamic late Holocene coastal plain palaeogeography

    NASA Astrophysics Data System (ADS)

    Pierik, H. J.; Cohen, K. M.; Stouthamer, E.

    2016-10-01

    The geomorphological development of Holocene coastal plains around the world has been studied since the beginning of the twentieth century from various disciplines, resulting in large amounts of data. However, the overwhelming quantities and heterogeneous nature of this data have caused the divided knowledge to remain inconsistent and fragmented. To keep improving the understanding of coastal plain geomorphology and geology, cataloguing of data and integration of knowledge are essential. In this paper we present a GIS that incorporates the accumulated data of the Netherlands' coastal plain and functions as a storage and integration tool for coastal plain mapped data. The GIS stores redigitised architectural elements (beach barriers, tidal channels, intertidal flats, supratidal flats, and coastal fresh water peat) from earlier mappings in separate map layers. A coupled catalogue-style database stores the dating information of these elements, besides references to source studies and annotations regarding changed insights. Using scripts, the system automatically establishes palaeogeographical maps for any chosen moment, combining the above mapping and dating information. In our approach, we strip the information to architectural element level, and we separate mapping from dating information, serving the automatic generation of time slice maps. It enables a workflow in which the maker can iteratively regenerate maps, which speeds up fine-tuning and thus the quality of palaeogeographical reconstruction. The GIS currently covers the late Holocene coastal plain development of the Netherlands. This period witnessed widespread renewed flooding along the southern North Sea coast, coinciding with large-scale reclamation and human occupation. Our GIS method is generic and can be expanded and adapted to allow faster integrated processing of growing amounts of data for many coastal areas and other large urbanising lowlands around the world. It allows maintaining actual data

  12. Preliminary geologic map of the Santa Barbara coastal plain area, Santa Barbara County, California

    USGS Publications Warehouse

    Minor, Scott A.; Kellogg, Karl S.; Stanley, Richard G.; Stone, Paul; Powell, Charles L.; Gurrola, Larry D.; Selting, Amy J.; Brandt, Theodore R.

    2002-01-01

    This report presents a new geologic digital map of the Santa Barbara coastal plain area at a compilation scale of 1:24,000 (one inch on the map = 2,000 feet on the ground) and with a horizontal positional accuracy of at least 20 m. This preliminary map depicts the distribution of bedrock units and surficial deposits and associated deformation underlying and adjacent to the coastal plain within the contiguous Santa Barbara and Goleta 7.5' quadrangles. A planned second version will extend the mapping westward into the adjoining Dos Pueblos Canyon quadrangle and eastward into the Carpinteria quadrangle. The mapping presented here results from the collaborative efforts of geologists with the U.S. Geological Survey Southern California Areal Mapping Project (SCAMP) (Minor, Kellogg, Stanley, Stone, and Powell) and the tectonic geomorphology research group at the University of California at Santa Barbara (Gurrola and Selting). C.L. Powell, II, performed all new fossil identifications and interpretations reported herein. T.R. Brandt designed and edited the GIS database,performed GIS database integration and created the digital cartography for the map layout. The Santa Barbara coastal plain is located in the western Transverse Ranges physiographic province along a west-trending segment of the southern California coastline about 100 km (62 mi) northwest of Los Angeles. The coastal plain region, which extends from the Santa Ynez Mountains on the north to the Santa Barbara Channel on the south, is underlain by numerous active and potentially active folds and partly buried thrust faults of the Santa Barbara fold and fault belt. Strong earthquakes that occurred in the region in 1925 (6.8 magnitude) and 1978 (5.1 magnitude) are evidence that such structures pose a significant earthquake hazard to the approximately 200,000 people living within the major coastal population centers of Santa Barbara and Goleta. Also, young landslide deposits along the steep lower flank of the Santa

  13. Importance of Small Isolated Wetlands for Herpetofaunal Diversity in Managed, Young Growth Forests in the Coastal Plain of South Carolina

    SciTech Connect

    Russell, K.R.; Guynn, D.C., Jr.; Hanlin, H.G.

    2002-03-27

    Assessment and comparison of richness, abundance and difference of herpetofauna at five small isolated wetlands located within a commercial forest landscape in the South Carolina Coastal Plain. Data indicates small isolated wetlands are focal points of herpetofaunal richness and abundance in managed coastal plain forest and contribute more to regional biodiversity than is implied by their small size or ephemeral hydrology.

  14. Distribution and elemental composition of suspended matter in Alaskan coastal waters

    SciTech Connect

    Feely, R.A.; Massoth, G.J.; Paulson, A.J.; Lamb, M.F.

    1980-09-01

    The distribution of suspended matter in the northeastern Gulf of Alaska is affected by a number of parameters which combine to form a unique distribution pattern. East of Kayak Island the surface particulate matter distributions are dominated by the discharge of sedimentary material from the coastal streams which drain the Beering, Guyot and Malaspina Glaciers. The major source of sedimentary material to the Gulf of Alaska is the Copper River. In general, concentrations of suspended matter in the northeast Gulf of Alaska are high at the surface with an average concentration of approximately 1.0 mg/l. Recent studies of oil spills in coastal waters containing high suspended loads have indicated rapid dispersal and removal of the oil by sorption onto particles along frontal zones.

  15. Oil and gas developments in Atlantic Coastal Plain and Outer Continental Shelf in 1985 and 1986

    SciTech Connect

    Amato, R.V.

    1987-10-01

    Drilling activity for 1985 was not reported previously due to the low level of activity. No exploratory drilling took place on the Atlantic outer continental shelf in 1985 or 1986. One shallow well was drilled onshore in Georgia on the Atlantic coastal plan in 1985, and 2 wells were completed in Georgia in 1986. Texaco drilled 6 core holes on the Virginia coastal plain in 1986. 2 tables.

  16. Luminescence chronology of Upper Pleistocene and Holocene aeolianites from Netanya South — Sharon Coastal Plain, Israel

    NASA Astrophysics Data System (ADS)

    Engelmann, Anette; Neber, Alexander; Frechen, Manfred; Wolfgang Boenigk; Ronen, Avraham

    2001-12-01

    The coastal cliff at Netanya South in the Sharon Coastal Plain of Israel was investigated with luminescence dating methods. Twenty-four samples were taken from the exposed aeolianites and intercalated paleosols. The 24 IRSL and 24 TL age estimates suggest that the lower 45 m of the section were deposited in Oxygen Isotope Stage 3. The uppermost 7 m of the section are of Holocene age and clearly separated by a hiatus of 20-30 ka from the lower part.

  17. Geochemistry of shallow ground water in coastal plain environments in the southeastern United States: Implications for aquifer susceptibility

    USGS Publications Warehouse

    Tesoriero, A.J.; Spruill, T.B.; Eimers, J.L.

    2004-01-01

    Ground-water chemistry data from coastal plain environments have been examined to determine the geochemical conditions and processes that occur in these areas and assess their implications for aquifer susceptibility. Two distinct geochemical environments were studied to represent a range of conditions: an inner coastal plain setting having more well-drained soils and lower organic carbon (C) content and an outer coastal plain environment that has more poorly drained soils and high organic C content. Higher concentrations of most major ions and dissolved inorganic and organic C in the outer coastal plain setting indicate a greater degree of mineral dissolution and organic matter oxidation. Accordingly, outer coastal plain waters are more reducing than inner coastal plain waters. Low dissolved oxygen (O2) and nitrate (NO 3-) concentrations and high iron (Fe) concentrations indicate that ferric iron (Fe (III)) is an important electron acceptor in this setting, while dissolved O2 is the most common terminal electron acceptor in the inner coastal plain setting. The presence of a wide range of redox conditions in the shallow aquifer system examined here underscores the importance of providing a detailed geochemical characterization of ground water when assessing the intrinsic susceptibility of coastal plain settings. The greater prevalence of aerobic conditions in the inner coastal plain setting makes this region more susceptible to contamination by constituents that are more stable under these conditions and is consistent with the significantly (p<0.05) higher concentrations of NO3- found in this setting. Herbicides and their transformation products were frequently detected (36% of wells sampled), however concentrations were typically low (<0.1 ??g/L). Shallow water table depths often found in coastal plain settings may result in an increased risk of the detection of pesticides (e.g., alachlor) that degrade rapidly in the unsaturated zone.

  18. Stormflow Response as a Function of Alluvial Storage in a Small Atlantic Coastal Plain Watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Total available groundwater storage in alluvial floodplains has been shown to have a significant impact upon stormflow within larger (16.7 to 50 km2) watersheds within the Atlantic Coastal Plain. Groundwater and streamflow data from a small (0.5 km2) watershed were examined to evaluate the temporal...

  19. Characterizing mercury concentrations and flux dynamics in a coastal plain watershed using multiple models

    EPA Science Inventory

    The primary goal was to asess Hg cycling within a small coastal plain watershed (McTier Creek) using multiple watershed models with distinct mathematical frameworks that emphasize different system dynamics; a secondary goal was to identify current needs in watershed-scale Hg mode...

  20. ASSESSING THE HYDROGEOLOGIC CLASSIFICATION SYSTEM IN MID-ATLANTIC COASTAL PLAIN STREAMS USING BENTHIC MACROINVERTEBRATES

    EPA Science Inventory

    Assessing classification systems that describe natural variation across regions is an important first step for developing indicators. We evaluated a hydrogeologic framework for first order streams in the mid-Atlantic Coastal Plain as part of the LIPS-MACS (Landscape Indicators f...

  1. APPLICATION OF A MULTIPURPOSE UNEQUAL-PROBABILITY STREAM SURVEY IN THE MID-ATLANTIC COASTAL PLAIN

    EPA Science Inventory

    A stratified random sample with unequal-probability selection was used to design a multipurpose survey of headwater streams in the Mid-Atlantic Coastal Plain. Objectives for data from the survey include unbiased estimates of regional stream conditions, and adequate coverage of un...

  2. Ground-water use in the coastal plain of Maryland, 1900-1980

    USGS Publications Warehouse

    Wheeler, J.C.; Wilde, F.D.

    1989-01-01

    This report presents groundwater withdrawal data from 1900 through 1980 for Maryland counties lying with the Coastal Plain physiographic province, as well as a summary section for the total Maryland Coastal Plain. The types of water use included are domestic, military, water supplier, industrial/commercial, and irrigation. The data were obtained from state and county reports, biannual pumpage reports submitted to the Maryland Water Resources Administration, communication with individual owners, and estimates based on existing published data. The amount of groundwater withdrawn from aquifers in the Maryland Coastal Plain in 1900 was approximately 26 million gallons per day (Mgal/d) compared to nearly 134 Mgal/d in 1980. Jurisdictions withdrawing more than 10 Mgal/d for most of the 80-year period were Anne Arundel and Baltimore Counties and Baltimore City. The greatest withdrawals for most of the early part of the period were for domestic and industrial/commercial uses; however, water-supplier use dominated after 1965. Groundwater use for irrigation became important in the Coastal Plain around 1960 and increased steadily from approximately 2 Mgal/d in 1960 to nearly 12 Mgal/d in 1980. (USGS)

  3. MINERALIZATION OF NITROGEN FROM BROILER LITTER AS AFFECTED BY SOIL TEXTURE IN THE SOUTHEASTERN COASTAL PLAIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A field study was conducted during 2004-2005 to determine nitrogen (N) mineralization of broiler litter (BL) in two Coastal Plain soils of differing texture, sandy or clayey. The soils were a Tifton loamy sand (fine-loamy, siliceous, thermic, Plinthic Kandiudults) and a Greenville sandy clay loam (...

  4. Nitrogen Mineralization of Broiler Litter Applied to Southeastern Coastal Plain Soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A field study was conducted to determine nitrogen (N) mineralization of broiler litter (BL) in two Coastal Plain soils of differing texture, sandy or clayey. The soils were a Tifton loamy sand (fine-loamy, siliceous, thermic, Plinthic Kandiudults) and a Greenville sandy clay loam (clayey, kaoliniti...

  5. Characterizing mercury concentrations and flux dynamics in a coastal plain watershed using multiple models and data

    EPA Science Inventory

    Mercury-related fish consumption advisories are widespread in the coastal plain of the southeastern U.S., where atmospherically deposited mercury interacts with an abundance of wetlands and high-dissolved organic carbon (DOC), acidic waters. Recent trends in decision making proce...

  6. Impact of biochar amendment on fertility of a southeastern Coastal Plain soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural soils in the southeastern USA Coastal Plain region have meager soil fertility characteristics due to their sandy textures, acidic pH values, kaolinitic clays, low cation exchange capacities (CEC), and diminutive soil organic carbon (SOC) contents. We hypothesized that biochar additions ...

  7. Projected climate change for the coastal plain region of Georgia, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Climatic patterns for the Coastal Plain region of Georgia, USA, centered on Tifton, Georgia (31 28 30N, 83 31 54W) were examined for long term patterns in precipitation and air temperature. Climate projections based upon output from seven Global Circulation Models (GCMs) and three future Green Hous...

  8. Air Emissions from Organic Soil Burning on the Coastal Plain of North Carolina

    EPA Science Inventory

    Emissions of trace gases and particles <10 and 2.5 microns aerodynamic diameter (PM10 and PM2.5, respectively) from fires during 2009-2011 on the North Carolina coastal plain were collected and analyzed. Carbon mass balance techniques were used to quantify emission factors (EFs)....

  9. Soil organic carbon dynamics in a sod-based rotation on coastal plain soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A frequently used cropping system in the southeastern Coastal Plain is an annual rotation of cotton (Gossypium hirsutum L.) and peanut (Arachis hypogaea L.) under conventional tillage (CT). The traditional peanut-cotton rotation (TR) often results in erosion and loss of soil organic carbon (SOC). In...

  10. Sediment loss and runoff from cropland in a Southeast Atlantic Coastal Plain landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Widespread implementation of conservation-tillage (CsT) systems during cotton and peanut production in the Atlantic Coastal Plain region (USA) has substantially reduced erosion and sediment loss. However, benefits of CsT in these cropping systems are being threatened by weather shifts that include i...

  11. Distribution of breeding shorebirds on the Arctic Coastal Plain of Alaska

    USGS Publications Warehouse

    Johnson, J.A.; Lanctot, Richard B.; Andres, B.A.; Bart, J.R.; Brown, S.C.; Kendall, S.J.; Payer, David C.

    2007-01-01

    Available information on the distribution of breeding shorebirds across the Arctic Coastal Plain of Alaska is dated, fragmented, and limited in scope. Herein, we describe the distribution of 19 shorebird species from data gathered at 407 study plots between 1998 and 2004. This information was collected using a single-visit rapid area search technique during territory establishment and early incubation periods, a time when social displays and vocalizations make the birds highly detectable. We describe the presence or absence of each species, as well as overall numbers of species, providing a regional perspective on shorebird distribution. We compare and contrast our shorebird distribution maps to those of prior studies and describe prominent patterns of shorebird distribution. Our examination of how shorebird distribution and numbers of species varied both latitudinally and longitudinally across the Arctic Coastal Plain of Alaska indicated that most shorebird species occur more frequently in the Beaufort Coastal Plain ecoregion (i.e., closer to the coast) than in the Brooks Foothills ecoregion (i.e., farther inland). Furthermore, the occurrence of several species indicated substantial longitudinal directionality. Species richness at surveyed sites was highest in the western portion of the Beaufort Coastal Plain ecoregion. The broad-scale distribution information we present here is valuable for evaluating potential effects of human development and climate change on Arctic-breeding shorebird populations. ?? The Arctic Institute of North America.

  12. Characteristics of Human Resources in the Rural Southeast Coastal Plain...With Emphasis on the Poor.

    ERIC Educational Resources Information Center

    McElveen, Jackson V.; And Others

    The objectives of this study were to determine the anatomy, typology, and conditions surrounding low incomes in the Coastal Plain of South Carolina and to determine the measures most suitable to reduce low income within the area. A sample of 1,000 households was selected and stratified among the 10 counties and between the open-country rural area…

  13. Hydrogeologic setting and potential for denitrification in ground water, coastal plain of southern Maryland

    USGS Publications Warehouse

    Krantz, David E.; Powars, David S.

    2000-01-01

    The types and distribution of Coastal Plain sediments in the Patuxent River Basin may contribute to relatively low concentrations of nitrate (typically less than 1 milligram per liter) in stream base flow because of the chemical reduction of dissolved nitrate (denitrification) in ground water. Water chemistry data from synoptic stream base-flow surveys in the Patuxent River Basin show higher dissolved nitrate concentrations in the Piedmont than in the Coastal Plain section of the watershed. Stream base flow reflects closely the chemistry of ground water discharging from the surficial (unconfined) aquifer to the stream. Because land use in the sampled subbasins is virtually the same in each section, differences in the physical and geochemical characteristics of the surficial aquifer may explain the observed differences in water chemistry. One possible cause of lower nitrate concentrations in the Coastal Plain is denitrification within marine sediments that contain chemically reduced compounds. During denitrification, the oxygen atoms on the nitrate (N03-) molecule are transferred to a reduced compound and N gas is produced. Organic carbon and ferrous iron (Fe2+), derived from the dissolution of minerals such as pyrite (FeS2) and glauconite (an iron aluminosilicate clay), can act as reducing substrates; these reduced chemical species are common in the marine and estuarine deposits in Southern Maryland. The spatial distribution of geologic units and their lithology (sediment type) has been used to create a map of the potential for denitrification of ground water in the surficial aquifer of the Coastal Plain in Southern Maryland.

  14. Forest transpiration from sap flux density measurements in a Southeastern Coastal Plain riparian buffer system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forested riparian buffers are prevalent throughout the Southeastern Coastal Plain Region of the United States (US). Because they make up a significant portion of the regional landscape, transpiration within these riparian buffers is believed to have an important impact on the hydrologic budget of r...

  15. ASSESSMENT FRAMEWORK FOR MID-ATLANTIC COASTAL PLAIN STREAMS USING BENTHIC MACRO INVERTEBRATES

    EPA Science Inventory

    A collaborative study among 6 states along the mid-Atlantic seaboard of the USA developed a consistent approach for collecting and interpreting macroinvertebrate data for low-gradient streams of the coastal plain. The study had 3 objectives: 1) to evaluate the validity of aggrega...

  16. Effect of habitat and foraging height on bat activity in the coastal plain of South Carolina.

    SciTech Connect

    Menzel, Jennifer, M.; Menzel, Michael A.; Kilgo, John C.; Ford, W. Mark; Edwards, John W.; McCracken, Gary F.

    2005-07-01

    A comparison of bat activity levels in the Coastal Plain of South Carolina among 5 habitat types: forested riparian areas, clearcuts, young pine plantations, mature pine plantations and pine savannas, using time expansion radio-microphones and integrated detectors to simultaneously monitor bat activity at three heights in each habitat type.

  17. Geostatistical Modeling of the Spatial Distribution of Sediment Oxygen Demand Within a Coastal Plain Blackwater Watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blackwater streams of the Georgia Coastal Plain are often listed as impaired due to chronically low DO levels. Previous research has shown that high sediment oxygen demand (SOD) values, a hypothesized cause of lowered DO within these waters, are significantly positively correlated with TOC within th...

  18. Ground-water withdrawals from the Coastal Plain of New Jersey, 1956-1980

    USGS Publications Warehouse

    Vowinkel, E.F.

    1984-01-01

    Withdrawals and site data for wells with a pump capacity of 100 ,000 gallons per day or greater in the Coastal Plain of New Jersey are stored in computer files for 1956-80. The data are aggregated by computer into tables, graphs and maps to show the distribution of ground-water withdrawals. Withdrawals are reported by type of use and aquifer for each county in the Coastal Plain. Public-supply wells withdraw the largest quantity of ground water in the Coastal Plain, followed by industrial and agricultural wells. In 1980 public-supply withdrawals were about 280 million gallons per day; the maximum monthly rate was about 355 million gallons per day in July, and the lowest was about 215 million gallons per day in February. Average industrial withdrawals were about 65 million gallons per day. Ground-water withdrawals used for agriculture vary significantly during the year. In 1980, about 75 percent of the agricultural withdrawals occurred from June through September. Several aquifers are used as sources of water supply in the Coastal Plain. Five regional aquifers are the major sources of water for public-supply, industrial, or agricultural use. In decreasing order of withdrawals in 1980, in million gallons per day, they are: The Potomac-Raritan-Magothy aquifer system, 243; Kirkwood-Cohansey aquifer system, 70; Atlantic City 800-foot sand, 21; Englishtown aquifer, 12; and the Wenonah-Mount Laurel aquifer system, 5. (USGS)

  19. Assessment of undiscovered sandstone-hosted uranium resources in the Texas Coastal Plain, 2015

    USGS Publications Warehouse

    Mihalasky, Mark J.; Hall, Susan M.; Hammarstrom, Jane M.; Tureck, Kathleen R.; Hannon, Mark T.; Breit, George N.; Zielinski, Robert A.; Elliott, Brent

    2015-12-02

    The U.S. Geological Survey estimated a mean of 220 million pounds of recoverable uranium oxide (U3O8 ) remaining as potential undiscovered resources in southern Texas. This estimate used a geology-based assessment method for Tertiary sandstone-hosted uranium deposits in the Texas Coastal Plain sedimentary strata (fig.1).

  20. Seasonal Hydrologic Impacts of Conservation Tillage for a Coastal Plain Soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation tillage has proven to be an effective water management tool for cotton production on sandy, drought-prone soils throughout the Coastal Plain. Conservation tillage increases crop residue at the surface, leading to reduced evaporation, reduced raindrop impact, increased infiltration, red...

  1. Research from the Coastal Plain Experiment Station, Tifton, Georgia, to minimize contamination in peanut

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scientists with the United States Department of Agriculture - Agricultural Research Service and scientists with the University of Georgia located at the Coastal Plain Experiment Station in Tifton, Georgia have been conducting research on aflatoxin contamination of peanut since the early 1960's. Ear...

  2. Artesian water in the Malabar coastal plain of southern Kerala, India

    USGS Publications Warehouse

    Taylor, George C.; Ghosh, P.K.

    1964-01-01

    The present report is based on a geological and hydrological reconnaissance during 1954 of the Malabar Coastal Plain and adjacent island area of southern Kerala to evaluate the availability of ground water for coastal villages and municipalities and associated industries and the potentialities for future development. The work was done in cooperation with the Geological Survey of India and under the auspices of the U.S. Technical Cooperation Mission to India. The State of Kerala, which lies near the southern tip of India and along the eastern shore of the Caspian Sea, contains a total area of 14,937 square miles. The eastern part of the state is s rugged mountainous highland which attains altitudes of more than 6,000 feet. This highland descends westward through piedmont upland to s narrow coastal plain, which reaches a maximum width of about 16 miles in the latitude of Shertalli. A tropical monsoon rain-forest climate prevails in most of Kerala, and annual rainfall ranges from 65 to 130 inches in the southern part of the coastal plain to as much a 200 inches in the highland. The highland and piedmont upland tracts of Kerala are underlain by Precambrian meamorphic and igneous rocks belonging in large parabola-the so-called Charnockite Series. Beneath ahe coastal plain are semiconsolidated asunconsolidated sedimentary deposits whose age ranges from Miocene to Recent. These deposits include sofa sandstone and clay shale containing some marl or limestone and sand, and clay and pea containing some gravel. The sofa sandstone, sand, and gravel beds constitute important aquifers a depths ranging from a few tens of feet to 400 feet or more below the land surface. The shallow ground war is under water-able or unconfined conditions, but the deeper aquifers contain water under artesian pressure. Near the coast, drilled wells tapping the deeper aquifers commonly flow with artesian heads as much as 10 to 12 feet above the land surface. The draft from existing wells in the

  3. Developing New Strategies for Coping with Weather: Work in Alaskan and Canadian Coastal Communities

    NASA Astrophysics Data System (ADS)

    Atkinson, D. E.

    2014-12-01

    A changing climate is manifested at ground level through the day to day weather. For all Northern residents - community, industrial, operational and response - the need to think about the weather is ever present. Northern residents, and in particular, indigenous community residents, fully understand implications of the weather, however, a comment that has been heard more often is that old ways of knowing are not as reliable as they once were. Weather patterns seem less consistent and subject to more rapid fluctuations. Compromised traditional ways of knowing puts those who need to travel or hunt at greater risk. One response to adapt to this emerging reality is to make greater use of western sources of information, such as weather data and charts provided by NOAA's National Weather Service or Environment Canada. The federal weather agencies have very large and complex forecasting regions to cover, and so one problem is that it can be difficult to provide perfectly tailored forecasts, that cover all possible problems, right down to the very local scale in the communities. Only those affected have a complete feel for their own concerns. Thus, key to a strategy to improve the utility of available weather information is a linking of local-scale manifestations of problematic weather to the larger-scale weather patterns. This is done in two ways: by direct consultation with Northern residents, and by installation of equipment to measure parameters of interest to residents, which are not already being measured. This talk will overview projects in coastal Alaska and Canada targeting this objective. The challenge of designing and conducting interviews, and then of harvesting relevant information, will be visited using examples from the three major contexts: coastal community, industrial, and operational. Examples of how local comments can be married to weather products will be presented.

  4. Historical and contemporary imagery to assess ecosystem change on the Arctic coastal plain of northern Alaska

    USGS Publications Warehouse

    Tape, Ken D.; Pearce, John M.; Walworth, Dennis; Meixell, Brandt W.; Fondell, Tom F.; Gustine, David D.; Flint, Paul L.; Hupp, Jerry W.; Schmutz, Joel A.; Ward, David H.

    2014-01-01

    In this report, we describe and make available a set of 61 georectified aerial images of the Arctic Coastal Plain (taken from 1948 to 2010) that were obtained by the USGS to inform research objectives of the USGS CAE Initiative. Here, we describe the origins, metadata, and public availability of these images that were obtained within four main study areas on the Arctic Coastal Plain: Teshekpuk Lake Special Area, Chipp River, the Colville River Delta, and locations along the Dalton Highway Corridor between the Brooks Range and Deadhorse. We also provide general descriptions of observable changes to the geomorphology of landscapes that are apparent by comparing historical and contemporary images. These landscape changes include altered river corridors, lake drying, coastal erosion, and new vegetation communities. All original and georectified images and metadata are available through the USGS Alaska Science Center Portal (search under ‘Project Name’ using title of this report) or by contacting ascweb@usgs.gov.

  5. Patterns of Seasonal Abundance and Social Segregation in Inland and Coastal Plain Swamp Sparrows in a Delaware Tidal Marsh

    EPA Science Inventory

    The Coastal Plain Swamp Sparrow (Melospiza georgiana nigrescens, CPSS) breeds in the coastal brackish marshes of the North American Mid-Atlantic States. During the non-breeding season, coastal brackish marshes are occupied by both this subspecies and two far more widespread inte...

  6. Mercury deposition in the snow pack of the arctic Alaskan coastal system

    NASA Astrophysics Data System (ADS)

    Sturm, M.; Blum, J. D.; Douglas, T. A.; Simpson, W.; Perovich, D. K.; Keeler, G.

    2006-12-01

    Extensive measurements of mercury (Hg), bromine, and ions in the snow pack on both the sea ice and tundra near Barrow, Alaska, show complex spatial and temporal patterns. Based on a comprehensive series of measurements made during the three winters between 2004 and 2006, elevated levels of Hg (50 to 500 ppt) were most often found when sampling diamond dust, surface hoar, frost flowers, or rime, all crystals grown from the vapor phase of water. Due to both the polar light cycle and near-surface re-emission processes, snow pack loading of Hg typically diminished rapidly with depth. Basal snow layers typically had levels less than 5 ppt, with most of the Hg concentrated in the top 10 cm. Similar snow pack loading was observed for snow on land and sea ice though with increasing distance inland (>100 km) the levels fell off. Observed levels were found to loosely correlate with mercury depletion events (MDEs). Hg loading remained elevated into the snow melt period. At the peak of snow melt run-off, Hg concentrations remained in excess of 10 ppt. Soil cores indicate increasing Hg loading with time, indicating that the run-off loading is due to winter deposition of Hg in the snow. We hypothesize that the bulk of the Hg loading in the coastal region occurs during winter. The deposition rate may be highly sensitive to sea ice conditions which are known to be changing as the climate warms.

  7. 27 CFR 9.207 - Outer Coastal Plain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... May, Atlantic, and Ocean Counties and portions of Salem, Gloucester, Camden, Burlington, and Monmouth... Joline Avenue; then (20) Proceed northeasterly on Joline Avenue to the Atlantic Ocean shoreline; then (21) Follow the Atlantic Ocean shoreline south, encompassing all coastal islands, onto the Trenton,...

  8. 27 CFR 9.207 - Outer Coastal Plain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... May, Atlantic, and Ocean Counties and portions of Salem, Gloucester, Camden, Burlington, and Monmouth... Joline Avenue; then (20) Proceed northeasterly on Joline Avenue to the Atlantic Ocean shoreline; then (21) Follow the Atlantic Ocean shoreline south, encompassing all coastal islands, onto the Trenton,...

  9. 27 CFR 9.207 - Outer Coastal Plain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... May, Atlantic, and Ocean Counties and portions of Salem, Gloucester, Camden, Burlington, and Monmouth... Joline Avenue; then (20) Proceed northeasterly on Joline Avenue to the Atlantic Ocean shoreline; then (21) Follow the Atlantic Ocean shoreline south, encompassing all coastal islands, onto the Trenton,...

  10. 27 CFR 9.207 - Outer Coastal Plain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... May, Atlantic, and Ocean Counties and portions of Salem, Gloucester, Camden, Burlington, and Monmouth... Joline Avenue; then (20) Proceed northeasterly on Joline Avenue to the Atlantic Ocean shoreline; then (21) Follow the Atlantic Ocean shoreline south, encompassing all coastal islands, onto the Trenton,...

  11. 27 CFR 9.207 - Outer Coastal Plain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... May, Atlantic, and Ocean Counties and portions of Salem, Gloucester, Camden, Burlington, and Monmouth... Joline Avenue; then (20) Proceed northeasterly on Joline Avenue to the Atlantic Ocean shoreline; then (21) Follow the Atlantic Ocean shoreline south, encompassing all coastal islands, onto the Trenton,...

  12. Factors Affecting Nitrate Delivery to Streams from Shallow Ground Water in the North Carolina Coastal Plain

    USGS Publications Warehouse

    Harden, Stephen L.; Spruill, Timothy B.

    2008-01-01

    An analysis of data collected at five flow-path study sites between 1997 and 2006 was performed to identify the factors needed to formulate a comprehensive program, with a focus on nitrogen, for protecting ground water and surface water in the North Carolina Coastal Plain. Water-quality protection in the Coastal Plain requires the identification of factors that affect the transport of nutrients from recharge areas to streams through the shallow ground-water system. Some basins process or retain nitrogen more readily than others, and the factors that affect nitrogen processing and retention were the focus of this investigation to improve nutrient management in Coastal Plain streams and to reduce nutrient loads to coastal waters. Nitrate reduction in ground water was observed at all five flow-path study sites in the North Carolina Coastal Plain, although the extent of reduction at each site was influenced by various environmental, hydrogeologic, and geochemical factors. Denitrification was the most common factor responsible for decreases in nitrate along the ground-water flow paths. Specific factors, some of which affect denitrification rates, that appeared to influence ground-water nitrate concentrations along the flow paths or in the streams include soil drainage, presence or absence of riparian buffers, evapotranspiration, fertilizer use, ground-water recharge rates and residence times, aquifer properties, subsurface tile drainage, sources and amounts of organic matter, and hyporheic processes. The study data indicate that the nitrate-reducing capacity of the buffer zone combined with that of the hyporheic zone can substantially lower the amount of ground-water nitrate discharged to streams in agricultural settings of the North Carolina Coastal Plain. At the watershed scale, the effects of ground-water discharge on surface-water quality appear to be greatly influenced by streamflow conditions and the presence of extensive riparian vegetation. Streamflow statistics

  13. Groundwater availability in the Atlantic Coastal Plain of North and South Carolina

    USGS Publications Warehouse

    Campbell, Bruce G.; Coes, Alissa L.

    2010-01-01

    The Atlantic Coastal Plain aquifers and confining units of North and South Carolina are composed of crystalline carbonate rocks, sand, clay, silt, and gravel and contain large volumes of high-quality groundwater. The aquifers have a long history of use dating back to the earliest days of European settlement in the late 1600s. Although extensive areas of some of the aquifers have or currently (2009) are areas of groundwater level declines from large-scale, concentrated pumping centers, large areas of the Atlantic Coastal Plain contain substantial quantities of high-quality groundwater that currently (2009) are unused. Groundwater use from the Atlantic Coastal Plain aquifers in North Carolina and South Carolina has increased during the past 60 years as the population has increased along with demands for municipal, industrial, and agricultural water needs. While North Carolina and South Carolina work to increase development of water supplies in response to the rapid growth in these coastal populations, both States recognize that they are facing a number of unanswered questions regarding availability of groundwater supplies and the best methods to manage these important supplies. An in-depth assessment of groundwater availability of the Atlantic Coastal Plain aquifers of North and South Carolina has been completed by the U.S. Geological Survey Groundwater Resources Program. This assessment includes (1) a determination of the present status of the Atlantic Coastal Plain groundwater resources; (2) an explanation for how these resources have changed over time; and (3) development of tools to assess the system's response to stresses from potential future climate variability. Results from numerous previous investigations of the Atlantic Coastal Plain by Federal and State agencies have been incorporated into this effort. The primary products of this effort are (1) comprehensive hydrologic datasets such as groundwater levels, groundwater use, and aquifer properties; (2) a

  14. Water quality of surficial aquifers in the Georgia-Florida Coastal Plain

    USGS Publications Warehouse

    Crandall, C.A.; Berndt, M.P.

    1996-01-01

    The National Water Quality Assessment Program of the U.S. Geological Survey established the Georgia-Florida Coastal Plain study unit in 1991. The ground-water study-unit survey was conducted in 1993 to provide a broad over-view of water quality in surficial aquifers. Three land resource provinces were included in the Georgia-Florida Coastal Plain study-unit survey: the Central Florida Ridge, the Coastal Flatwoods, and the Southern Coastal Plain. The U.S. Geological Survey sampled 37 wells in surficial aquifers, 18 in the Coastal Flatwoods and 19 in the Southern Coastal Plain. The Florida Department of Environmental Protection sampled 27 wells tapping surficial aquifers in the Central Florida Ridge as part of the background ground-water quality monitoring network from 1985 through 1989. The data were used to characterize water quality in surficial aquifers of the Central Florida Ridge. Results of the study-unit survey indicated that dissolved solids concentrations in ground water were mostly less than 100 mg/L (milligrams per liter). Higher medians of pH, specific conductance, and concentrations of calcium, bicarbonate, and dissolved solids were measured in samples from the Central Florida Ridge compared to the Southern Coastal Plain and Coastal Flatwoods, probably because of a greater percentage of carbonate minerals in aquifer materials. The U.S. Environmental Protection Agency secondary maximum contaminant level for iron of 300 ug/L (micrograms per liter) in drinking water was exceeded in 15 of 45 samples. Concentrations of nitrate as nitrogen were less than 3.0 mg/L in most samples (74 percent), indicating little or no influence from human activity. Only five samples (9 percent) had concentrations above 10 mg/L, the U.S. Environmental Protection Agency maximum contaminant level for nitrate concentration in drinking water. Significantly lower median concentrations of nitrate were measured in samples from polyvinyl chloride monitoring wells with diameters less

  15. The oligocene stratigraphic framework of the coastal plain of the southeastern United States

    SciTech Connect

    Huddlestun, P.F. )

    1993-03-01

    Four lithostratigraphic associations are recognized in the Oligocene of the southeastern Coastal Plain: (1) an eastern Gulf of Mexico stratigraphic association, (2) a Gulf Trough stratigraphic association, (3) a Florida Bank stratigraphic association and (4), an Atlantic continental shelf stratigraphic association. Oligocene formations and faunal provinces appear to be directly related to the stratigraphic associations. The Vicksburg Group is restricted to the eastern Gulf of Mexico continental shelf stratigraphic association and to the Coastal Plain north and west of the Gulf Trough. The Gulf Trough stratigraphic association includes the Ochlockonee Formation, Wolf Pit Dolostone, Okapilco Limestone, and Bridgeboro Limestone (the Bridgeboro Limestones occurs only on and adjacent to the northern and southern flanks of the trough). The Florida Bank stratigraphic association is largely restricted to the area south of the Gulf Trough and includes the Ellaville Limestone, Suwannacoochee Dolostone, and Suwannee Limestone (the Suwannee Limestone also occurs immediately north of the Gulf Trough in the central Georgia Coastal Plain). The Cooper and Lazaretto Creek Formations are restricted to the Atlantic continental shelf stratigraphic association and occur only in the coastal area of Georgia, South Carolina, and beneath the continental shelf. Three faunal provinces (or subprovinces) are recognized in the southeastern Coastal Plain during the Oligocene: (1) a Gulf of Mexico continental shelf faunal province that characterizes the Gulf Trough and the region north and west of the trough, (2) a Florida province characteristic and largely restricted to the Florida Bank and (3), an Atlantic continental shelf faunal province. Through the Early Oligocene, the trough marked the limits of the Gulf of Mexico and Florida provinces.

  16. Pleistocene Shorelines and Coastal Rivers: Sensitive Indicators of Quaternary Faults, Atlantic Coastal Plain, USA

    NASA Astrophysics Data System (ADS)

    Bartholomew, M. J.; Rich, F. J.

    2002-05-01

    Eight possible active faults beneath Quaternary Coastal Plain sediments are indicated by models showing expected patterns of shoreline regression and river deflections along tectonically inactive and active (where subsurface faults may affect surface processes) parts of the passive margin. Non-tectonic processes produce consistently spaced parallel shorelines and an absence of river deflections or seaward deflections of shorelines by major deltas with spacing dependent upon sediment influx rates. Differential regional uplift will cause divergence of shorelines toward, and deflection of rivers away from the end with greater uplift. Tectonic models show shoreline regression with a shoreline-parallel fault that is either seaward-side-up (SSU) or seaward-side-down (SSD) or with a shoreline-perpendicular fault (SPF). SSU interrupts non-tectonic patterns with convex-seaward deflections and wider spacing of older shorelines across uplifts and river deflections toward uplift-margins. SSD produces a convex-landward deflection and wider spacing of younger shorelines on the down-dropped side of faults and river deflections toward uplift-margins. SPF produces: convex-seaward deflections with wider spacing of older shorelines across uplifts and river deflections toward uplift-margins; convex-landward deflection and wider spacing of younger shorelines on down-dropped sides of faults where river deflections merge toward the lowest area; shorelines are discontinuous and may be difficult to correlate across faults. SPF patterns in the vicinity of the 1886 Charleston, SC earthquake indicate a NW-trending, 50-km long, NE-side-up fault active since Early Pleistocene near the Ashley River and suggest a similar 30-km long fault near the North Edisto River and a NW-trending, 50-km long, SW-side-up fault near the Broad River. Variations of SPF patterns in NC suggest E-W-trending, 150-km long, N-side-up faults extending westward from both Cape Fear and Cape Lookout and possibly a shorter

  17. Gulf coastal plain evolution in West Louisiana: Heavy mineral provenance and Pleistocene alluvial chronology

    NASA Astrophysics Data System (ADS)

    Mange, Maria A.; Otvos, Ervin G.

    2005-12-01

    High Resolution Heavy Mineral Analysis (HRHMA) of late Pleistocene terrace samples, their Tertiary source rocks, and modern river sediments provided an effective tool for reconstructing sediment provenance and mapping heavy mineral provinces in southwest Louisiana. Each province, linked to a discrete source region, represents Pleistocene fluvial channel belts within which depositional activity was controlled by periods of climate, sediment supply, and sea level changes. Four coastal heavy mineral provinces have been identified. The Northern Province (NP), drained by the lower reaches of the Sabine and Calcasieu Rivers underlies level mid- and late Pleistocene coastal terrace surfaces and is distinguished by high-grade metamorphic assemblages (kyanite, staurolite, sillimanite) and abundant zircon, probably of Ouachita Mts. derivation. Transporting eroded Cretaceous, Tertiary, and Pleistocene coastal plain deposits, the modern Calcasieu and Sabine River sands in west-central and southwest Louisiana and east Texas, display identical heavy mineral composition to that of the NP. Level Late Pleistocene coastal terrace areas in the east represent the Red River Province (RRP) with dominant epidote, tourmaline, garnet, and zircon. Its mineralogy is influenced significantly by Paleozoic-Mesozoic sedimentary units that frame the drainage basin upstream. Modern Red River sands differ in their spectra both from Red River Pleistocene coastal terrace and valley terrace deposits, interpreted by temporal fluctuations in sediment supply initiating a variable contribution of detritus from different sources. Tributaries that drain formations with high concentrations of high-grade metamorphic minerals also affected Red River valley Pleistocene terrace deposits in west-central Louisiana, enriching them in kyanite and staurolite. The Mississippi Province (MP) occupies the eastern-southeastern area of the low, flat, gently seaward-sloping Prairie coastal terrace. Whereas modern

  18. ERTS-1 applied for structural and morphological investigtions case studies. 1: Los Angeles, California. 2: Coastal plain, New Jersey

    NASA Technical Reports Server (NTRS)

    Kedar, E. Y.

    1973-01-01

    Two major earth's resources management problems, the application of ERTS-1 imagery for geomorphotectonics, and subsequently seismic-risk, earthquake, and mineral exploration applications are discussed. Case studies are presented for Los Angeles, California, and New Jersey coastal plain.

  19. Stable isotope enrichment in paleowaters of the southeast Atlantic coastal plain, United States

    USGS Publications Warehouse

    Plummer, L.N.

    1993-01-01

    Paleowaters from the Floridan aquifer system in the southeastern Atlantic coastal plain have higher D/H and 18O/16O ratios than local Holocene ground water. Maximum ??18O enrichments in ground water having adjusted radiocarbon ages of 20,000 to 26,000 years are 0.7 to 2.3 per mil. The trend in isotopic enrichment in paleowaters is the reverse of that normally observed in continental glacial age ground water. Dissolved nitrogen and argon concentrations indicate, however, that the average recharge temperature was 5.3??C cooler than that today. The data indicate cool conditions in the southeast Atlantic coastal plain during the last glacial maximum, with recharge limited primarily to late summer tropical cyclones and hurricanes.

  20. Selected aquifer-test information for the coastal plain aquifers of South Carolina

    USGS Publications Warehouse

    Aucott, W.R.; Newcome, Roy

    1986-01-01

    Aquifer and well hydraulic characteristics were determined from more than 100 multiple-well and single-well aquifer tests in the Coastal Plain of South Carolina and tabulated by county. Multiple-well aquifer tests were analyzed by the This method for nonleaky aquifers and the Hantush-Jacob method for leaky aquifers. Single-well tests were analyzed by straight line solution techniques for drawdown and recovery tests. Specific-capacity data are presented for many areas where aquifer-test information is sparse. The characteristics determined are based largely on well performance tests conducted by well drillers and consulting engineers. Although use of this information has many limitations, it has value in establishing transmissivity and storage coefficient values for the Coastal Plain aquifers. (Peters-PTT)

  1. Stable isotope enrichment in paleowaters of the southeast atlantic coastal plain, United States

    SciTech Connect

    Plummer, L.N. )

    1993-12-24

    Paleowaters from the Floridan aquifer system in the southeastern Atlantic coastal plain have higher D/H and [sup 18]O/[sup 16]O ratios than local Holocene groundwater. Maximum [delta][sup 18]O enrichments in groundwater having adjusted radiocarbon ages of 20,000 to 26,000 years are 0.7 to 2.3 per mil. The trend in isotopic enrichment in paleowaters is the reverse of that normally observed in continental glacial age groundwater. Dissolved nitrogen and argon concentrations indicate, however, that the average recharge temperature was 5.3[degrees]C cooler than that today. The data indicate cool conditions in the southeast Atlantic coastal plain during the last glacial maximum, with recharge limited primarily to late summer tropical cyclones and hurricanes.

  2. Stratigraphic nomenclature and geologic sections of the Gulf Coastal Plain of Texas

    USGS Publications Warehouse

    Baker, E.T.

    1995-01-01

    Geologic sections showing the subsurface delineation of approximately 100 Stratigraphic units composing the Mesozoic and Cenozoic Eras illustrate the interrelation of these units across most of the Gulf Coastal Plain of Texas. The geologic names that constitute the nomenclature have been published, and the vast majority are approved for use by the U.S. Geological Survey. Four dip sections and four strike sections, extending from the land surface to a maximum of about 18,000 feet below sea level, provide continuity of correlation from the outcrop to the deep subsurface. Stratigraphic units containing water with less than 3,000 milligrams per liter concentration of dissolved solids are shown on the geologic sections and serve as an indicator of water quality in the Gulf Coastal Plain of Texas.

  3. Stable isotope enrichment in paleowaters of the southeast atlantic coastal plain, United States.

    PubMed

    Plummer, L N

    1993-12-24

    Paleowaters from the Floridan aquifer system in the southeastern Atlantic coastal plain have higher D/H and (18)O/(16)O ratios than local Holocene ground water. Maximum delta(18)O enrichments in ground water having adjusted radiocarbon ages of 20,000 to 26,000 years are 0.7 to 2.3 per mil. The trend in isotopic enrichment in paleowaters is the reverse of that normally observed in continental glacial age ground water. Dissolved nitrogen and argon concentrations indicate, however, that the average recharge temperature was 5.3 degrees C cooler than that today. The data indicate cool conditions in the southeast Atlantic coastal plain during the last glacial maximum, with recharge limited primarily to late summer tropical cyclones and hurricanes.

  4. Correlation of lineaments with soil gas anomalies in the Atlantic Coastal Plain

    SciTech Connect

    Wyatt, D.E. |; Richers, D.

    1994-08-23

    Results from a soil gas survey, performed in the Atlantic Coastal Plain and centered on the US Department of Energy Savannah River Site discovered areas of anomalous (greater than one standard deviation above the mean) methane, ethane, propane, hydrogen and carbon dioxide. A lineament study was performed to investigate whether these anomalies may be associated with fractures or faults and therefore be sourced in basement rocks. The lineament study used a regional aeromagnetic map, various scale topographic maps and a Landsat image. The results of the study suggest the following: (1) correcting for barometric pumping effects, the soil gas anomalies have a strong coincidence with lineations, (2) comparing linear features discernible on a variety of sources mapped at different scales allows for a combined data set to be formed that may define a lineation zone, and (3) linear trends compare favorably with suspected structural trends for the coastal plain.

  5. Water-Level Changes in Aquifers of the Atlantic Coastal Plain, Predevelopment to 2000

    USGS Publications Warehouse

    dePaul, Vincent T.; Rice, Donald E.; Zapecza, Otto S.

    2008-01-01

    The Atlantic Coastal Plain aquifer system, which underlies a large part of the east coast of the United States, is an important source of water for more than 20 million people. As the population of the region increases, further demand is being placed on those ground-water resources. To define areas of past and current declines in ground-water levels, as well as to document changes in those levels, historical water-level data from more than 4,000 wells completed in 13 regional aquifers in the Atlantic Coastal Plain were examined. From predevelopment to 1980, substantial water-level declines occurred in many areas of the Atlantic Coastal Plain. Regional variability in water-level change in the confined aquifers of the Atlantic Coastal Plain resulted from regional differences in aquifer properties and patterns of ground-water withdrawals. Within the Northern Atlantic Coastal Plain, declines of more than 100 ft were observed in New Jersey, Delaware, Maryland, Virginia, and North Carolina. Regional declines in water levels were most widespread in the deeper aquifers that were most effectively confined?the Upper, Middle, and Lower Potomac aquifers. Within these aquifers, water levels had declined up to 200 ft in southern Virginia and to more than 100 ft in New Jersey, Delaware, Maryland, and North Carolina. Substantial water-level declines were also evident in the regional Lower Chesapeake aquifer in southeastern New Jersey; in the Castle Hayne-Piney Point aquifer in Delaware, Maryland, southern Virginia and east-central North Carolina; in the Peedee-Severn aquifer in east-central New Jersey and southeastern North Carolina; and in the Black Creek-Matawan aquifer in east-central New Jersey and east-central North Carolina. Conversely, declines were least severe in the regional Upper Chesapeake aquifer during this period. In the Southeastern Coastal Plain, declines of more than 100 ft in the Chattahoochee River aquifer occurred in eastern South Carolina and in southwestern

  6. Hydrogeology of the Southeastern Coastal Plain aquifer system in Mississippi, Alabama, Georgia, and South Carolina

    USGS Publications Warehouse

    Renken, Robert A.

    1996-01-01

    The Southeastern Coastal Plain aquifer system consists of a thick sequence of unconsolidated to poorly consolidated Cretaceous and Tertiary rocks that extend from Mississippi to South Carolina. Four regional sand and gravel aquifers are separated by three regional confining units of clay, shale, and chalk that do not conform everywhere to stratigraphic boundaries. The change in geologic facies is the most important factor controlling the distribution of transmissivity within the aquifer system.

  7. Mercury dynamics in a Coastal Plain watershed: Insights from multiple models and empirical data

    NASA Astrophysics Data System (ADS)

    Golden, H. E.; Knightes, C. D.; Conrads, P. A.; Davis, G. M.; Feaster, T.; Benedict, S.; Journey, C.; Brigham, M. E.; Bradley, P. M.

    2011-12-01

    Interactions among atmospherically deposited mercury, abundant wetlands, and surface waters with elevated acidity and dissolved organic carbon (DOC) often lead to widespread mercury-related fish consumption advisories in the Coastal Plain of the southeastern United States (US). However, the science behind understanding mercury dynamics in these mixed land cover, Coastal Plain watersheds is just beginning to emerge. Watershed models are important tools for answering questions related to watershed mercury cycling - including the spatial and temporal variations in surface water mercury concentrations and fluxes - particularly when limited data exist and multiple models with different underlying dynamics are available. We quantify total mercury (HgT) concentrations and fluxes to the outlet of McTier Creek Watershed, located in the upper Coastal Plain of South Carolina, US, an area with more diverse land cover, a larger drainage area, and different geophysical setting than many previous mercury studies in North America (primarily from small forested headwater boreal or northern forested catchments). We apply three independently developed watershed mercury models with distinct mathematical frameworks that emphasize different system processes. Because spatially-explicit watershed scale mercury modeling is a recent advancement, the use of multiple models combined with data affords broader insights to HgT dynamics in the watershed. As a result, we employ a spatially-explicit grid based watershed mercury model (GBMM), the spatially-explicit VELMA-Hg model, and the semi-empirical TOPLOAD-Hg model for HgT concentration and flux calculations. We use the S-LOADEST model for seasonal HgT fluxes, while measured in-stream HgT concentrations and fluxes provide additional insights and data for model calibrations. Our findings begin to elucidate important abiotic processes controlling HgT, areas within the landscape where HgT at the outlet is derived, and potential governing dynamics

  8. Identifying riparian buffer effects on stream nitrogen in southeastern coastal plain watersheds.

    PubMed

    Christensen, Jay R; Nash, Maliha S; Neale, Anne

    2013-11-01

    Within the Southeastern (SE) Coastal Plain of the U.S., numerous freshwaters and estuaries experience eutrophication with significant nutrient contributions by agricultural non-point sources (NPS). Riparian buffers are often used to reduce agricultural NPS yet the effect of buffers in the watershed is difficult to quantify. Using corrected Akaike information criterion (AICc) and model averaging, we compared flow-path riparian buffer models with land use/land cover (LULC) models in 24 watersheds from the SE Coastal Plain to determine the ability of riparian buffers to reduce or mitigate stream total nitrogen concentrations (TNC). Additional models considered the relative importance of headwaters and artificial agricultural drainage in the Coastal Plain. A buffer model which included cropland and non-buffered cropland best explained stream TNC (R (2) = 0.75) and was five times more likely to be the correct model than the LULC model. The model average predicted that current buffers removed 52 % of nitrogen from the edge-of-field and 45 % of potential nitrogen from the average SE Coastal Plain watershed. On average, 26 % of stream nitrogen leaked through buffered cropland. Our study suggests that stream TNC could potentially be reduced by 34 % if buffers were adequately restored on all cropland. Such estimates provide realistic expectations of nitrogen removal via buffers to watershed managers as they attempt to meet water quality goals. In addition, model comparisons of AICc values indicated that non-headwater buffers may contribute little to stream TNC. Model comparisons also indicated that artificial drainage should be considered when accessing buffers and stream nitrogen.

  9. Distribution, abundance, and habitat affinities of the Coastal Plain Swamp Sparrow

    USGS Publications Warehouse

    Beadell, J.; Greenberg, R.; Droege, S.; Royle, J. Andrew

    2003-01-01

    We examined the distribution and abundance of the Coastal Plain Swamp Sparrow (Melospiza georgiana nigrescens) at previously occupied sites and points within potential habitat. We found Swamp Sparrows throughout their formerly documented range except in southern Chesapeake Bay. Swamp Sparrows were most common in the Mullica River region of New Jersey where we detected individuals at 78% of systematically chosen points with a mean count of 4.1 birds/point. The percentages of points with positive detections in. the regions of Delaware River (39%), eastern Delaware Bay (23%), western Delaware Bay (34%), and Tuckahoe River (31%) were lower. The mean count of birds/point was between 0.4 and 0.6 in these regions. A higher resolution Poisson model of relative abundance suggested that the greatest concentrations of Swamp Sparrows occurred not only in the Mullica River area but also along northwestern Delaware Bay. Regression analysis of Swamp Sparrow counts and habitat features identified shrubs (Iva frutescens and Baccharis halimifolia) as a key habitat component. By applying density estimates generated by DISTANCE (Thomas et al. 1998) to the approximate area of potential shrub habitat along Delaware Bay, we estimated that the core population of Coastal Plain Swamp Sparrows was less than 28,000 pairs. We recommend that the Coastal Plain Swamp Sparrow be listed as a subspecies of concern by state and local governments because of its relatively small population size, restricted distribution in the mid-Atlantic region, and narrow habitat requirements.

  10. Coastal morphodynamics and Chenier-Plain evolution in southwestern Louisiana, USA: A geomorphic model

    NASA Astrophysics Data System (ADS)

    McBride, Randolph A.; Taylor, Matthew J.; Byrnes, Mark R.

    2007-08-01

    Using 28 topographic profiles, air-photo interpretation, and historical shoreline-change data, coastal processes were evaluated along the Chenier Plain to explain the occurrence, distribution, and geomorphic hierarchy of primary landforms, and existing hypotheses regarding Chenier-Plain evolution were reconsidered. The Chenier Plain of SW Louisiana, classified as a low-profile, microtidal, storm-dominated coast, is located west and downdrift of the Mississippi River deltaic plain. This Late-Holocene, marginal-deltaic environment is 200 km long and up to 30 km wide, and is composed primarily of mud deposits capped by marsh interspersed with thin sand- and shell-rich ridges ("cheniers") that have elevations of up to 4 m. In this study, the term "ridge" is used as a morphologic term for a narrow, linear or curvilinear topographic high that consists of sand and shelly material accumulated by waves and other physical coastal processes. Thus, most ridges in the Chenier Plain represent relict open-Gulf shorelines. On the basis of past movement trends of individual shorelines, ridges may be further classified as transgressive, regressive, or laterally accreted. Geomorphic zones that contain two or more regressive, transgressive, or laterally accreted ridges are termed complexes. Consequently, we further refine the Chenier-Plain definition by Otvos and Price [Otvos, E.G. and Price, W.A., 1979. Problems of chenier genesis and terminology—an overview. Marine Geology, 31: 251-263] and define Chenier Plain as containing at least two or more chenier complexes. Based on these definitions, a geomorphic hierarchy of landforms was refined relative to dominant process for the Louisiana Chenier Plain. The Chenier Plain is defined as a first-order feature (5000 km 2) composed of three second-order features (30 to 300 km 2): chenier complex, beach-ridge complex, and spit complex. Individual ridges of each complex type were further separated into third-order features: chenier, beach

  11. Connecting Indigenous Knowledge to Thaw Lake Cycle Research on the Arctic Coastal Plain of Alaska

    NASA Astrophysics Data System (ADS)

    Eisner, W. R.; Cuomo, C. J.; Hinkel, K. M.; Jones, B. M.; Hurd, J.

    2005-12-01

    Thaw lakes cover about 20% of the Arctic Coastal Plain of Alaska. Another 26% is scarred by basins that form when lakes drain, and these drained thaw-lake basins are sites for preferential carbon accumulation as plant biomass. Recent studies in the continuous permafrost zone of Western Siberia suggest that lakes have been expanding in the past several decades in response to regional warming. Anticipated regional warming would likely mobilize sequestered soil organic carbon, resulting in the emission of CO2 and CH4. Our understanding of the processes leading to thaw lake formation, expansion, and drainage in northern Alaska has been limited because models are specific to the flat, young Outer (seaward) Coastal Plain comprising 1/3 of the region. Furthermore, spatial and temporal analysis of lake dynamics is largely restricted to the period since 1948, when aerial photographs first became available across large regions of the Coastal Plain. In order to fill these gaps, we have been interviewing Iñupiaq elders, hunters, and berry pickers from the villages of Atqasuk and Barrow. The objective of these interviews is to obtain accounts of lake formation, expansion and drainage that have occurred within living or oral memory, and extend the record back several generations. To date, we have interviewed fifteen Iñupiat; most of these are people who travel the tundra frequently and have done so for decades. They have first-hand experience of lake drainage, sea cliff and river bank erosion, permafrost degradation, and other landscape changes. Many informants expressed concern that landscape changes are occurring at an increasingly rapid rate. They have identified lakes that have drained, areas where the permafrost is thawing, and places where the sea and river coastline is eroding. We have been able to corroborate reports of lake drainage from our informants with a series of aerial photographs, satellite images, and radiocarbon dates. In many instances, the elders have

  12. Effects of sea level rise on deltaic coastal marshlands, Mississippi River deltaic plain

    SciTech Connect

    Ramsey, K.E.; Penland, S. ); Roberts, H.H.; Coleman, J.M. )

    1990-05-01

    Low-relief deltaic coastal plains commonly experience land loss because of the cumulative effects of natural and human-induced processes. Although it is difficult to separate the individual factors within the overall process, interplay between these factors can result in a rate of relative sea level rise greater than the natural rate of coastal-plain aggradation that causes land loss. Between 1956 and 1978, about 11,400 and 2,490 ha of marsh were lost in east Texas and Mississippi, respectively. Louisiana's loss was 18,755 ha. Relative sea level rise over the last 65 yr has averaged 0.23 cm/yr in the Gulf and as much as 1-1.5 cm/yr in the delta plain. The Environmental Protection Agency predicts the rate of sea level rise to increase over the next century. Rates of relative sea level rise for the Gulf of Mexico are expected to increase from 0.23-1.5 cm/yr to 0.6-3.7 cm/yr. The current rate of relative sea level rise and land loss in the subsiding Mississippi delta is a response that can be expected for many US coastal areas over the next century. With the predicted change, the Mississippi River delta complex will experience dramatically increased rates of land loss. Isles Dernieres will disappear by the year 2000, and Plaquemines and Terrebonne marshes will be gone between 2020 and 2080. Based on the lowest predicted sea level rise rate, by the year 2100, the delta plain could be reduced from 150.9 {times} 10{sup 3} ha to 29.8 x 10{sup 3} ha or to 4.9 {times} 10{sup 3} ha if calculations are based on the highest rate.

  13. Novel microsatellites for Calibrachoa heterophylla (Solanaceae) endemic to the South Atlantic Coastal Plain of South America1

    PubMed Central

    Silva-Arias, Gustavo Adolfo; Mäder, Geraldo; Bonatto, Sandro L.; Freitas, Loreta B.

    2015-01-01

    Premise of the study: Calibrachoa heterophylla (Solanaceae) is a petunia species restricted to the South Atlantic Coastal Plain of South America and presents a recent history of colonization from continental to coastal environments and diversification following the formation of the Coastal Plain during the Quaternary period. Methods and Results: This study reports a suite of 16 microsatellite loci for C. heterophylla. The applicability of these markers was assessed by genotyping 57 individuals from two natural populations. Of the 16 described loci, 12 were found to be polymorphic. Successful cross-amplification tests were obtained using 12 Calibrachoa species. Conclusions: The development of microsatellite markers will be useful to recover the contemporary history of the colonization of the Coastal Plain and to provide information for the conservation of this endemic species. PMID:26191462

  14. Estimating SGD flux in the Pingtung Plain coastal area by using Radon and Radium isotopes

    NASA Astrophysics Data System (ADS)

    Li Chang, Yao; Chieh Su, Chih

    2015-04-01

    In the past two decades, submarine groundwater discharge (SGD) has been recognized as an important pathway to transport material into coastal area. Our study area is located at Pingtung Plain which is the second largest plain in Taiwan with three major rivers, including Gaoping, Donggang and Linbian Rivers, flow through the plain. The Gaoping River, which has the largest drainage area, flows throughout the central part of the plain. The Pingtung Plain composed by four aquifers in different depths (0, 50, 100, and 200 m) and each layer extends to coastal area. Groundwater is an important water resource for local agriculture and aquaculture. However, the long-term over-pumping induced subsidence problem makes salinization at some coastal area. Some previous studies pointed out the SGD accounts for 80% or more of the mass of freshwater in Fangshan coast, depends on salinity and stable isotopes research. In this study, the radioactive tracers, Radon (222Rn, T1/2=3.8 d) and short-lived Ra isotopes (223Ra, T1/2=11.4 d & 224Ra, T1/2=3.6 d) are used in tracing SGD off the Pingtung Plain. During 2013 to 2014, the terrestrial water samples were collected from Gaoping, Donggang, Linbian Rivers and springs in different seasons. We also conducted two coastal waters cruises by using R/V Ocean Researcher 3 (OR3-1768 and 1799 cruises in May and September 2014). Continuous 222Rn was measured by RAD7 equipped with RAD-AQUA system and large volume (20 L) seawater samples were collected by CTD/Rosette water sampler with Niskin sterile bottles. Water samples were flow through Mn-fiber (flow rate < 1 LPM) to concentrate the Ra isotopes, and counted via RaDeCC system. In spatial variation, our result shows the excess 224Ra in the downstream of Gaoping River (2.39 dpm 100L-1) is higher than upstream (1.09 dpm 100L-1). It indicates the groundwater input may play an important role at the downstream of Gaoping River. For temporal variation, excess 224Ra in the Gaoping River are higher in wet

  15. Coastal Evolution of the Mississippi River Chenier Plain: A Geomorphic Process-Response Model

    NASA Astrophysics Data System (ADS)

    McBride, R. A.; Taylor, M. J.; Byrnes, M. R.

    2007-12-01

    Using 28 topographic profiles, air-photo interpretation, and historical shoreline-change data, coastal processes were evaluated along the Mississippi River Chenier Plain to explain the occurrence, distribution, and geomorphic hierarchy of primary landforms. The Louisiana Chenier Plain, classified as a low-profile, microtidal, storm- dominated coast, is located west and downdrift of the Mississippi River deltaic plain. This late-Holocene, marginal-deltaic environment is 200 km long, less than 30 km wide, and composed of mud deposits capped by marsh interspersed with thin sand- and shell-rich ridges ("cheniers") that are less than 4 m in elevation. Most Chenier-Plain ridges represent open-Gulf paleoshorelines. Past shoreline morphodynamics allow ridges to be classified as transgressive (cheniers), regressive (beach ridges), or laterally accreted (spits). Geomorphic zones that contain two or more regressive, transgressive, or laterally accreted ridges are termed complexes. Consequently, we further refine the Chenier-Plain definition by Otvos and Price (1979, Marine Geology) and define Chenier Plain as containing at least two or more chenier complexes. As such, a geomorphic hierarchy of landforms is devised relative to dominant coastal process. The Chenier Plain is defined as a first-order feature (5000 km2) composed of three second-order features (30 to 300 km2): chenier complex, beach ridge complex, and spit complex. Individual ridges of each complex type were further separated into third-order features: chenier, beach ridge, and spit. To understand long-term evolution of the Chenier Plain, modern tidal-inlet processes operating at Sabine, Calcasieu, and Mermentau river entrances were also examined relative to the inlet-stability ratio. Prior to human modification and stabilization efforts, the Mermentau River entrance is classified as wave-dominated, Sabine Pass as tide-dominated, and Calcasieu Pass as tide-dominated to mixed. Hoyt (1969, American Association of

  16. Geohydrology of the Englishtown Formation in the northern Coastal Plain of New Jersey

    USGS Publications Warehouse

    Nichols, W.D.

    1977-01-01

    The Englishtown Formation of the Matawan Group of Late Cretaceous age is exposed in the western part of the New Jeresy Coastal Plain along a northeast-southwest trending zone extending from Raritan Bay to Delaware Bay. In outcrop, in the northern part of the Coastal Plain, the Englishtown typically consists of a series of thin, cross-stratified, fine- to medium-grained lignitic quartz sand beds intercalated with thin beds of sandy silty clay and clayey silt, ranging in total thickness from about 140 feet (43 meters) near Raritan Bay to about 50 feet (15 meters) near Trenton. In the subsurface of the northern part of the Coastal Plain, the formation retains most of the lithologic characteristics displayed in outcrop. In northern and eastern Ocean County the Englishtown can be subdivided into three distinct lithologic units; upper and lower units of quartz sand with thin interbeds of dark sandy silt, separated by a thick sequence of sandy and clayey lignitic silt. The confined part of the aquifer in the Englishtown Formation is utilized as a source of water over an area of about 1,100 square miles (2,849 square kilometers) of the New Jersey Coastal Plain and is an important source of supply in Monmouth and northern Ocean Counties. The annual average rate of withdrawal from the aquifer in the two-county area increased from 5.5 million gallons per day (0.24 cubic meters per second) in 1959 to 9.5 million gallons per day (0.4 cubic meters per second) in 1970. Water levels in parts of this area were declining 8 to 12 feet (2.4 to 3.6 meters) per year as of 1970 and they declined as much as 140 feet (43 meters) between 1959 and 1970 near pumping centers. The aquifer transmissivity ranges from 2,400 square feet per day to 650 square feet per day (223 square meters per day to 60 square meters per day); the estimated hydraulic conductivity ranges from about 11 feet per day to 20 feet per day (3.3 meters per day to 6.1 meters per day); and the storage coefficient ranges from

  17. High-resolution correlation of coastal plain strata for definition of reservoir attributes

    SciTech Connect

    Navarre, J.C.; Cross, T.A.

    1995-08-01

    Three type of stratigraphic cycles are recognized in coastal-plain strata of the MesaVerde Group (Cretaceous) San Juan Basin, Colorado. The cycle types change as a function of accommodation and geographic position. The cycles record oscillations of base level and concomitant oscillations of increasing and decreasing accommodation. Coastal-plain strata were traced physically into shoreface strata to establish temporal equivalency of strata within the two environments, and thus ensure correct recognition of base-level rise and fall hemicycles in coastal-plain strata. Potential reservoir units are channel belt sandstones and backbarrier and bay sandstones which occur in two of the cycle types. These sandstones change geometry, connectivity, and volumes within cycles, reflecting changes in accommodation, the types of original geomorphic elements within environments, and sediment preservation during base-level cycles. The occurrence of different facies successions in the different types of cycles establishes the empirical basis for recognizing such cycles with well-log inversion techniques. One type of stratigraphic cycle, which occurs in the lowest accommodation condition of the Mesa Verde Group, is an alternation between laterally amalgamated channels and either crevasse splay/crevasse channel complexes or floodplain vertical accretion deposits and soils. Laterally amalgamated channel sandstones accumulated during base-level rise hemicycles. The third type of stratigraphic cycle also occurs in the maximum accommodation conditions, but in a more seaward position than the previous type. Like the first, this type of stratigraphic cycle comprises an alternation of two types of facies associations. This type is an alternation between tidally dominated estuarine and bay sandstones and mudstones which accumulated during base-level rise, and shallowing-up and bed-thickening up hummocky cross stratified back-barrier and bay sandstones which accumulated during base-level fall.

  18. Pleistocene sea-level fluctuations and human evolution on the southern coastal plain of South Africa

    NASA Astrophysics Data System (ADS)

    Compton, John S.

    2011-03-01

    Humans evolved in Africa, but where and how remain unclear. Here it is proposed that the southern coastal plain (SCP) of South Africa may have served as a geographical point of origin through periodic expansion and contraction (isolation) in response to glacial/interglacial changes in sea level and climate. During Pleistocene interglacial highstands when sea level was above -75 m human populations were isolated for periods of 360-3400 25-yr generations on the SCP by the rugged mountains of the Cape Fold Belt, climate and vegetation barriers. The SCP expands five-fold as sea level falls from -75 to -120 m during glacial maxima to form a continuous, unobstructed coastal plain accessible to the interior. An expanded and wet glacial SCP may have served as a refuge to humans and large migratory herds and resulted in the mixing of previously isolated groups. The expansive glacial SCP habitat abruptly contracts, by as much as one-third in 300 yr, during the rapid rise in sea level associated with glacial terminations. Rapid flooding may have increased population density and competition on the SCP to select for humans who expanded their diet to include marine resources or hunted large animals. Successful adaptations developed on an isolated SCP are predicted to widely disperse during glacial terminations when the SCP rapidly contracts or during the initial opening of the SCP in the transition to glacial maxima. The hypothesis that periodic expansion and contraction of the SCP, as well as the coastal plain of North Africa, contributed to the stepwise origin of our species over the last 800 thousand years (kyr) is evaluated by comparing the archeological, DNA and sea-level records. These records generally support the hypothesis, but more complete and well dated records are required to resolve the extent to which sea-level fluctuations influenced the complex history of human evolution.

  19. Reactivated basement structures in the central Savannah River area and their relationship to coastal plain deformation

    SciTech Connect

    Cumbest, R.J.; Price, V. ); Temples, T.J. ); Fallaw, W.C. . Dept. of Geology); Snipes, D.S. . Dept. of Earth Sciences)

    1993-03-01

    Structural surface mapping and geophysical studies have identified several faults in the crystalline basement and overlying Coastal Plain sedimentary sequences in the central Savannah River area. Major subsurface basement shear zones occur parallel to and near Upper Three Runs Creek and Tinker Creek and are associated with linear aeromagnetic anomalies. Reflection seismic imaging of the basement shows a band of southeast dipping events parallel to Upper Three Runs Creek. Drill core from basement contain phyllonites, mylonites, fault breccia and pseudotachylite. The magnetic anomalies also mark the boundary separating greenschist facies metavolcanic rocks from amphibolite facies felsic gneiss, schist, and amphibolite. These features are similar to those that characterize other Paleozoic faults of the Eastern Piedmont Fault system. Reflection seismic imaging shows the sub-Cretaceous unconformity as well defined and easily identified event as well as easily traced laterally extensive events in Coastal Plain sequences. The unconformity and sedimentary sequences are faulted or deformed in several locations which also coincide with changes in dip of the unconformity. In the vicinity of Upper Three Runs Creek the unconformity shows a broad warping across which the elevation drops to the southeast and sedimentary sequences show a marked rate of thickening southeast. This indicates deformation of the basement exerted a control on deposition of the Coastal Plain sediments with down to the southeast movement. The basement shear zones are closely associated with the Dunbarton basin and are probable reactivated Paleozoic structures associated with extensional basin development as commonly seen associated with extensional basins on the east coast of North America.

  20. Evidence for a major, tectonically active structure beneath the coastal plain of North and South Carolina

    SciTech Connect

    Marple, R.T.; Talwani, P. . Geology Dept.); Olson, O.

    1994-03-01

    Evaluation of Landsat imagery, aerial photography, potential field data, and topographic maps have revealed a linear, [approximately]400-km-long, NNE-trending zone in the coastal plain of North and South Carolina. This zone is composed of subtle topographic highs, aeromagnetic anomalies, and in some locations mapped and inferred faults. It is also associated with a zone of river anomalies (ZRA). Various data suggest that the ZRA may be associated with tectonic activity on a large right-lateral strike-slip fault system. The ZRA in the South Carolina coastal plain is defined by an [approximately]15-km-wide NNE-trending zone that crosses NW-SE-flowing rivers. Along this zone the rivers are characterized by river bends that are convex toward the NNE, incised channels, changes in river patterns, and convex-upward longitudinal profiles. In the coastal plain and eastern Slate Belt of North Carolina the ZRA (width yet to be determined) displays a slightly more northeasterly trend that is highlighted by linear aeromagnetic anomalies and right-lateral offsets of larger rivers crossing its trend. This feature is not traceable across the southern flank of the Cape Fear Arch and north of this area the ZRA's trend is offset [approximately]15 km toward the east (right step geometry) from that of the ZRA in South Carolina. Analyses of geologic and geophysical data further indicate that these two zones may be the result of ongoing tectonic uplift along a NNE-trending right-lateral strike-slip fault zone possibly associated with recent seismicity near Charleston.

  1. Assessment of forest plantations from low altitude aerial photography. [North Carolina coastal plains

    NASA Technical Reports Server (NTRS)

    Nelson, H. A.

    1977-01-01

    Vertical color, and color-infrared, aerial photography obtained from altitudes between 183 m and 915 m provide a cost effective method of determining tree survival and height growth in pine plantations on the North Carolina Coastal Plain. All interpretations were performed by professional forestry personnel from the original 70 mm color transparencies. Prompt assessment of tree survival is necessary if failed spots are to be successfully replanted. Counts of living trees made after the third growing season, and sometimes only two growing seasons after planting, are accurate enough to permit planning of replanting operations without extensive ground surveys.

  2. Impacts of sewage effluent on tree survival, water quality and nutrient removal in coastal plain swamps

    SciTech Connect

    Kuenzler, E.J.

    1987-09-01

    An investigation was conducted of the impacts of sprayed municipal sewage on swamp tree survival and the effects of the swamp system on nutrient concentrations below the outfalls on two streams on the coastal plain of North Carolina. Effluent was discharged to one swamp stream by aerial spraying and to the other stream by way of a small ditch. Ninety-eight percent of the trees struck directly by the spray were dead within 18 months of the date spraying began. Both swamp systems removed sufficient quantities of nitrogen and phosphorus within a few kilometers to account for virtually all of the sewage nutrient load to the swamps.

  3. Oil plays in Smackover reservoirs of the eastern Gulf Coastal Plain

    SciTech Connect

    Mancini, E.A.; Mink, R.M.; Tew, B.H.; Kopaskamerkel, D.C.; Mann, S.D. )

    1991-03-01

    Five Smackover (Upper Jurassic, Oxfordian) oil plays can be delineated in the eastern Gulf Coastal Plain. These include the basement ridge play, the regional peripheral fault trend play, the Mississippi interior salt basin play, the Mobile graben fault system play, and the Wiggins arch complex play. Plays are recognized by basinal position, relationships to regional structural features, and characteristic petroleum traps. Within two plays, subplays can be distinguished based on oil gravities and reservoir characteristics. Reservoirs are distinguished primarily by depositional setting and diagenetic overprint. The geology and petroleum characteristics of these plays are discussed.

  4. Potential Oil Production from Coastal Plain of Arctic National Wildlife Refuge: Updated Assessment

    EIA Publications

    2000-01-01

    The Energy Information Administration (EIA) received a letter (dated March 10, 2000) from Senator Frank H. Murkowski as Chairman of the Senate Committee on Energy and Natural Resources requesting an EIA Service Report with plausible scenarios for the Arctic National Wildlife Refuge (ANWR) supply development consistent with the most recent U.S. Geological Survey resource assessments. This service report is prepared in response to the request of Senator Murkowski. It focuses on the ANWR coastal plain, a region currently restricted from exploration and development, and updates EIA's 1987 ANWR assessment.

  5. The Maryland Coastal Plain Aquifer Information System: A GIS-based tool for assessing groundwater resources

    USGS Publications Warehouse

    Andreasen, David C.; Nardi, Mark R.; Staley, Andrew W.; Achmad, Grufron; Grace, John W.

    2016-01-01

    Groundwater is the source of drinking water for ∼1.4 million people in the Coastal Plain Province of Maryland (USA). In addition, groundwater is essential for commercial, industrial, and agricultural uses. Approximately 0.757 × 109 L d–1 (200 million gallons/d) were withdrawn in 2010. As a result of decades of withdrawals from the coastal plain confined aquifers, groundwater levels have declined by as much as 70 m (230 ft) from estimated prepumping levels. Other issues posing challenges to long-term groundwater sustainability include degraded water quality from both man-made and natural sources, reduced stream base flow, land subsidence, and changing recharge patterns (drought) caused by climate change. In Maryland, groundwater supply is managed primarily by the Maryland Department of the Environment, which seeks to balance reasonable use of the resource with long-term sustainability. The chief goal of groundwater management in Maryland is to ensure safe and adequate supplies for all current and future users through the implementation of appropriate usage, planning, and conservation policies. To assist in that effort, the geographic information system (GIS)–based Maryland Coastal Plain Aquifer Information System was developed as a tool to help water managers access and visualize groundwater data for use in the evaluation of groundwater allocation and use permits. The system, contained within an ESRI ArcMap desktop environment, includes both interpreted and basic data for 16 aquifers and 14 confining units. Data map layers include aquifer and ­confining unit layer surfaces, aquifer extents, borehole information, hydraulic properties, time-series groundwater-level data, well records, and geophysical and lithologic logs. The aquifer and confining unit layer surfaces were generated specifically for the GIS system. The system also contains select groundwater-quality data and map layers that quantify groundwater and surface-water withdrawals. The aquifer

  6. Development of an empirical model of episodic acidification in Coastal Plain streams

    SciTech Connect

    Gerritsen, J.; Dietz, J.; Wilson, H.

    1991-07-01

    The study forms part of an ongoing process to develop understanding of the effects of acidic deposition in Maryland and to develop tools for managing its consequences on natural resources. Episodic acidification is common in poorly buffered streams of the Coastal Plain of Maryland and may harm sensitive life stages of migratory fish that spawn in small sreams of the region. The study described here was intended to test and validate the modeling approach with independent data and to improve the confidence of model predictions.

  7. Late Cenozoic stages and molluscan zones of the U.S. Middle Atlantic Coastal Plain.

    USGS Publications Warehouse

    Blackwelder, B. W.

    1981-01-01

    Pliocene to Holocene deposits of the U.S.Atlantic Coastal Plain from Maryland to Georgia are divided into four stages and four substages using molluscan biostratigraphic data. These divisions are the Wiltonian and Burwellian Stages (early Pliocene), Gouldian and Windyan Substages of the Colerainian Stage (late Pliocene to early Pleistocene), and Myrtlean and Yongesian Substages of the Longian Stage (late Pleistocene to Holocene). These stages may be recognized from Florida to as far north as Massachusetts and will facilitate correlation with other regions.-Author

  8. The Pilbara coast: a riverine coastal plain in a tropical arid setting, northwestern Australia

    NASA Astrophysics Data System (ADS)

    Semeniuk, V.

    1993-03-01

    The unifying feature of the Pilbara Coast of northwestern Australia is that it is a sedimentary repository for a range of rivers that drains a high-relief Precambrian rocky hinterland and discharges sediments along a coastal plain which fronts a wave-dominated environment in a tropical arid climate. The combination of fluvial and shoreline accretion processes, coastal cementation, coastal erosion, and ancestral landform architecture, such as residual Pleistocene limestone ridges and large outcrops of Precambrian bedrock, has produced a complex coastal system during the Quaternary. As a result, the coast is dominated by active deltas, beach/dune shores, inactive, eroding parts of deltas and their barriers, limestone barrier coasts, bays associated with eroded limestone barriers, and archipelago/ria coasts. Quaternary sediments throughout the area, while varied in their distribution and history at the smaller scales, exhibit a recurring pattern of lithotopes and lithologies in the region. There are three main Quaternary suites: Pleistocene red siliciclastic sediments (alluvium, deltaic sediments, and aeolian sand) that form an inland zone; Pleistocene limestones that form local barriers; and a Holocene system, within which are the sedimentary suites of deltas, beach/dunes, tidal-flats, and tidal-embayments.

  9. Shorebird abundance and distribution on the coastal plain of the Arctic National Wildlife Refuge

    USGS Publications Warehouse

    Brown, S.; Bart, J.; Lanctot, Richard B.; Johnson, J.A.; Kendall, S.; Payer, D.; Johnson, J.

    2007-01-01

    The coastal plain of the Arctic National Wildlife Refuge hosts seven species of migratory shorebirds listed as highly imperiled or high priority by the U.S. Shorebird Conservation Plan and five species listed as Birds of Conservation Concern by the U.S. Fish and Wildlife Service. During the first comprehensive shorebird survey of the 674 000 ha "1002 Area" on the coastal plain, we recorded 14 species of breeding shorebirds at 197 rapidly surveyed plots during June 2002 and 2004. We also estimated detection ratios with a double counting technique, using data collected at 37 intensively studied plots located on the North Slope of Alaska and northern Canada. We stratified the study area by major habitat types, including wetlands, moist areas, uplands, and riparian areas, using previously classified Landsat imagery. We developed population estimates with confidence limits by species, and estimated the total number of shorebirds in the study area to be 230 000 (95% CI: 104 000-363 000), which exceeds the biological criterion for classification as both a Western Hemisphere Shorebird Reserve Network Site of International Importance (100 000 birds) and a Ramsar Wetland of International Importance (20 000 birds), even when conservatively estimated. Species richness and the density of many species were highest in wetland or riparian habitats, which are clustered along the coast. ?? The Cooper Ornithological Society 2007.

  10. Is there continental crust underneath the northern Natal Valley and the Mozambique Coastal Plains?

    NASA Astrophysics Data System (ADS)

    Leinweber, Volker Thor; Jokat, W.

    2011-07-01

    To draw conclusions about the crustal nature and history of the Natal Valley and the Mozambique Ridge, systematic potential field data were obtained during the AISTEK III cruise with R/V Pelagia in 2009. This paper presents and interprets the results of that expedition. The new magnetic data reveal a pattern of linear magnetic spreading anomalies, NW-SE trending in the southwestern part of the Mozambique Ridge and E-W trending on its central part. The Ariel Graben, which separates the Mozambique Ridge from the Northern Natal Valley, is represented by a pronounced negative anomaly in the magnetic- as well as the free-air gravity field. The Northern Natal Valley bears a complicated pattern of anomalies with mainly SW-NE trends. In the Northern Natal Valley, no indications for a continent-ocean-boundary between continental crust in the north and oceanic crust in the south exist, either in the free-air gravity or in the magnetic field. The magnetic wavelengths of the Mozambique Coastal Plains are similar to those of the Northern Natal Valley and the Mozambique Ridge. Particularly in the gravity data, the Mozambique coastal plains, the Northern Natal Valley and the Mozambique Ridge appear as one continuous geological province. We interpret the region from the Mateke-Sabi monocline in the north to the southwestern tip of the Mozambique Ridge as mainly being floored by thickened oceanic crust.

  11. Influence of coarse woody debris on the soricid community in southeastern Coastal Plain pine stands.

    SciTech Connect

    Davis, Justin, C.; Castleberry, Steven, B.; Kilgo, John, C.

    2010-07-01

    Shrew abundance has been linked to the presence of coarse woody debris (CWD), especially downed logs, in many regions in the United States. We investigated the importance of CWD to shrew communities in managed upland pine stands in the southeastern United States Coastal Plain. Using a randomized complete block design, 1 of the following treatments was assigned to twelve 9.3-ha plots: removal (n 5 3; all downed CWD _10 cm in diameter and _60 cm long removed), downed (n 5 3; 5-fold increase in volume of downed CWD), snag (n 5 3; 10-fold increase in volume of standing dead CWD), and control (n 5 3; unmanipulated). Shrews (Blarina carolinensis, Sorex longirostris, and Cryptotis parva) were captured over 7 seasons from January 2007 to August 2008 using drift-fence pitfall trapping arrays within treatment plots. Topographic variables were measured and included as treatment covariates. More captures of B. carolinensis were made in the downed treatment compared to removal, and captures of S. longirostris were greater in downed and snag compared to removal. Captures of C. parva did not differ among treatments. Captures of S. longirostris were positively correlated with slope. Our results suggest that abundance of 2 of the 3 common shrew species of the southeastern Coastal Plain examined in our study is influenced by the presence of CWD.

  12. Supergroup stratigraphy of the Atlantic and Gulf Coastal Plains (Middle? Jurassic through holocene, Eastern North America)

    USGS Publications Warehouse

    Weems, R.E.; ,; Edwards, L.E.

    2004-01-01

    An inclusive supergroup stratigraphic framework for the Atlantic and Gulf Coastal Plains is proposed herein. This framework consists of five supergroups that 1) are regionally inclusive and regionally applicable, 2) meaningfully reflect the overall stratigraphic and structural history of the Coastal Plains geologic province of the southeastern United States, and 3) create stratigraphic units that are readily mappable and useful at a regional level. Only the Marquesas Supergroup (Lower Cretaceous to lowest Upper Cretaceous) has been previously established. The Trent Supergroup (middle middle Eocene to basal lower Miocene) is an existing name here raised to supergroup rank. The Minden Supergroup (Middle? through Upper Jurassic), the Ancora Supergroup (Upper Cretaceous to lower middle Eocene), and the Nomini Supergroup (lower Miocene to Recent) are new stratigraphic concepts proposed herein. In order to bring existing groups and formations into accord with the supergroups described here, the following stratigraphic revisions are made. 1) The base of the Shark River Formation (Trent Supergroup) is moved upward. 2) The Old Church Formation is removed from the Chesapeake Group (Nomini Supergroup) and moved to the Trent Supergroup without group placement. 3) The Tiger Leap and Penney Farms formations are removed from the Hawthorn Group (Nomini Supergroup) and moved to the Trent Supergroup without group placement. 4) The Piney Point and Chickahominy formations are removed from the Pamunkey Group (Ancora Supergroup) and moved to the Trent Supergroup without group placement. 5) the Tallahatta Formation is removed from the Claiborne Group (Trent Supergroup) and placed within the Ancora Supergroup without group placement.

  13. Quaternary climates and sea levels of the u.s. Atlantic coastal plain.

    PubMed

    Cronin, T M; Szabo, B J; Ager, T A; Hazel, J E; Owens, J P

    1981-01-16

    Uranium-series dating of corals from marine deposits of the U.S. Atlantic Coastal Plain coupled with paleoclimatic reconstructions based on ostracode (marine) and pollen (continent) data document at least five relatively warm intervals during the last 500,000 years. On the basis of multiple paleoenvironmental criteria, we determined relative sea level positions during the warm intervals, relative to present mean sea level, were 7 +/- 5 meters at 188,000 years ago, 7.5 +/- 1.5 meters at 120,000 years ago, 6.5 +/- 3.5 meters at 94,000 years ago, and 7 +/- 3 meters at 72,000 years ago. The composite sea level chronology for the Atlantic Coastal Plain is inconsistent with independent estimates of eustatic sea level positions during interglacial intervals of the last 200,000 years. Hydroisostatic adjustment from glacial-interglacial sea level fluctuations, lithospheric flexure, and isostatic uplift from sediment unloading due to erosion provide possible mechanisms to account for the discrepancies. Alternatively, current eustatic sea level estimates for the middle and late Quaternary may require revision.

  14. Estimating contributions of nitrate and herbicides from groundwater to headwater streams, northern Atlantic Coastal Plain, USA

    USGS Publications Warehouse

    Ator, Scott; Denver, Judith M.

    2012-01-01

    Groundwater transport often complicates understanding of surface-water contamination. We estimated the regional flux of nitrate and selected herbicides from groundwater to nontidal headwater streams of the Atlantic Coastal Plain (New Jersey through North Carolina) based on late-winter or spring base-flow samples from 174 streams. Sampled streams were selected randomly, and flux estimates are based on resulting population estimates rather than on empirical models, which have been used previously for similar estimates. Base-flow flux in the estimated 8,834 headwater streams of the study area are an estimated 21,200 kg/day of nitrate (as N) and 5.83, 0.565, and 20.7 kg/day of alachlor, atrazine, and metolachlor (and selected degradates), respectively. Base-flow flux of alachlor and metolachlor is <3% of the total base-flow flux of those compounds plus degradates. Base-flow flux of nitrate and herbicides as a percentage of applications is typically highest in well-drained areas and lowest in areas with abundant poor drainage and anoxic conditions. In Coastal Plain watersheds of Albemarle and Pamlico Sounds, <2% of applied nitrogen reaches headwater streams as base flow. On the Delmarva Peninsula part of the Chesapeake Bay watershed, however, more than 10% of such applications are transported through groundwater to streams, and base-flow nitrate flux represents 70% of total nitrogen flux in headwater streams.

  15. Geochronology of upper Paleocene and lower Eocene strata, eastern Gulf Coastal Plain

    SciTech Connect

    Mancini, E.A.; Tew, B.H. Geological Survey of Alabama, Tuscaloosa, AL )

    1994-03-01

    Four samples of glauconitic sand from upper Paleocene and lower Eocene strata of the eastern Gulf Coastal Plain were analyzed for conventional potassium-argon (K-Ar) age determination. Results from these analyses are as follows: Coal Bluff Marl Member of the Naheola Formation of the Midway Group (58.2 [+-] 1.5 MA), Ostrea thirsae beds of the Nanafalia Formation of the Wilcox Group (56.3 [+-] 1.5 MA), upper Tuscahoma Sand of the Wilcox Group (54.5 [+-] 1.4 MA), and Bashi Marl Member of the Hatchetigbee Formation of the Wilcox Group (53.4 [+-] 1.4 MA). The Nanafalia Formation (Wilcox Group) disconformably overlies the Naheola Formation (Midway Group), and based on the data presented here, the age of this unconformity is bracketed between 59.7 and 54.8 MA. The Paleocene-Eocene Epoch boundary occurs in the Wilcox Group and coincides with the lithostratigraphic contact of the upper Paleocene Tuscahoma Sand with the lower eocene Hatchetigbee Formation. The age of this boundary, which is also an unconformity, can be placed between 55.9 and 52.0 MA. The K-Ar age dates for this boundary in the Gulf Coastal Plain compare favorably with the numerical limits placed on the Paleocene-Eocene boundary in the published literature. Generally, the Paleocene-Eocene Epoch boundary is reported as approximately 54 to 55 MA.

  16. Contribution of landbird migration to the biological diversity of the northwest gulf coastal plain

    USGS Publications Warehouse

    Barrow, W.C.; Hamilton, R.B.; Powell, M.A.; Ouchley, K.

    2000-01-01

    This study examined seasonal diversity and feeding behavior of those avian species utilizing that region of the Northwest Gulf Coastal Plain known as the Chenier Plain. Field observations were conducted at three forested locations on coastal cheniers for three years (1993-95) in the spring and at one location for three years (1996-98) in autumn to determine species presence and diet. One hundred and twenty-eight species were present during the spring and 103 species in autumn. The majority of these species were migrants (103 species in spring and 89 species in autumn) and the majority of these were Nearctic/Neotropical species (73 species in spring and 66 species in autumn). The diet of these migrants was more variable than expected. Many insectivorous species were observed to consume seeds, fruit and nectar as well as insects. Because of these varied diets, many species serve as seed dispersers, occasional pollinators and important predators of herbivorus insects. Wooded areas were found to be important in providing food, cover and water for migrating species. A review of historical changes in the landscape of this area is presented and management practices designed to restore wooded habitat to this area are proposed.

  17. Microbial acetogenesis as a source of organic acids in ancient Atlantic Coastal Plain sediments

    USGS Publications Warehouse

    Chapelle, F.H.; Bradley, P.M.

    1996-01-01

    Field and laboratory evidence shows that deeply buried (90-888 m) fine-grained sediments of the Atlantic Coastal Plain contain viable acetogenic microorganisms, and that these microorganisms actively produce organic acids. Concentrations of formate, acetate, and propionate in pore waters extracted from fine-grained sediments ranged from 50 ??M to 5 mM and were much higher than in adjacent pore waters associated with sandy sediments (<2 ??M). Laboratory studies showed that asceptically cored fine-grained sediments incubated under a H2 atmosphere produced formate and acetate, and that H14CO-3 was converted to 14C-acetate and 14C-formate over time. An enrichment culture of these acetogenic microorganisms was recovered from one long-term incubation that showed the presence of several morphologically distinct gram-positive, rod-shaped bacteria. These microorganisms were capable of growth under autotrophic (H2 + CO2), heterotrophic (syringate), and mixotrophic (H2 + CO2 + syringate) conditions. These results suggest that microbial acetogenesis, rather than abiotic processes, is the most important organic acid-producing mechanism during low-temperature (???30 ??C) diagenesis of Atlantic Coastal Plain sediments.

  18. Documentation of revisions to the regional aquifer system analysis model of the New Jersey coastal plain

    USGS Publications Warehouse

    Voronin, Lois M.

    2004-01-01

    The model, which simulates flow in the New Jersey Coastal Plain sediments, developed for the U.S. Geological Survey Regional Aquifer System Analysis (RASA) program was revised. The RASA model was revised with (1) a rediscretization of the model parameters with a finer cell size, (2) a spatially variable recharge rate that is based on rates determined by recent studies and, (3) ground-water withdrawal data from 1981 to 1998. The RASA model framework, which subdivided the Coastal Plain sediments into 10 aquifers and 9 confining units, was preserved in the revised model. A transient model that simulates flow conditions from January 1, 1968 to December 31, 1998, was constructed using 21 stress periods. The model was calibrated by attempting to match the simulated results with (1) estimated base flow for five river basins, (2) measured water levels in long-term hydrographs for 28 selected observation wells, and (3) potentiometric surfaces in the model area for 1978, 1983, 1998, 1993, and 1998 conditions. The estimated and simulated base flow in the five river basins compare well. In general, the simulated water levels matched the interpreted potentiometric surfaces and the measured water levels of the hydrographs within 25 feet.

  19. Paleolimnological reconstruction of Holocene environments in wetland ponds of the Upper Atlantic Coastal Plain

    SciTech Connect

    Gaiser, E.E.; Taylor, B.E.

    1995-06-01

    The paleohydrology and paleoecology of Carolina bays and upland wetland ponds on the Savannah River Site (SRS), Aiken, South Carolina are being investigated to reconstruct environmental changes brought about by long-term variation in the climate of the Upper Atlantic Coastal Plain. Cores were taken in transacts through Flamingo Bay, a temporary pond on the SRS, to determine the vertical and horizontal sediment particle size and diatom, plant phytolith and sponge spicule microfossils. Stratigraphic data were used to construct a 3-dimensional map of the basin. In conjunction with archaeological data from the rim of the pond, physical stratigraphic data indicate a decrease in pond size and depth during the past 10,000 years. In order to infer past ecological settings from the fossil record, a survey to determine microhabitat requirements of regional diatom flora was undertaken in 43 temporary ponds throughout the coastal plain of South Carolina. The relationships between diatom assemblages and environmental variables were assessed using canonical correspondence analysis. Variables contributing significantly to the diatom-environment relationship included surface core location (near shore or pelagic), water depth, hydroperiod, microhabitat substrate, and sampling date, in order of decreasing influence. Strong relationships of diatom assemblages to drought frequency within and among basins provides a reliable basis for water level reconstruction in upland temporary ponds.

  20. Alaskan Voices.

    ERIC Educational Resources Information Center

    Achatz, Mary, Ed.; Caldera, Debra, Ed.; Saylor, Brian; DeGross, Denny

    This paper examines the attitudes of adults and teenagers in 10 predominantly rural Alaskan communities toward their own health and well-being and that of children and families in their community. The communities were located across the state and ranged in size from populations of under 900 to over 50,000. The proportion of Alaska Natives in the…

  1. Age and correlation of tertiary sediments in the western South Carolina Coastal Plain

    SciTech Connect

    Laws, R.A.; Harris, W.B.; Zullo, V.A.; Fallaw, W.C.; Price, V.

    1987-01-01

    Integration of coastal onlap stratigraphy, calcareous nannofossil, dinoflagellate, and megafossil biostratigraphy provide new data for interpretation of age and interregional correlation of Paleocene to Oligocene deposits of the western South Carolina Coastal Plain. Clastic and calcareous sediments examined in cores and outcrops in the vicinity of the Savannah River Plant record at least seven coastal onlap cycles. Basal Tertiary sediments of the Ellenton Formation represent cycles TA1.1 - 1.3 and contain dinoflagellates of Midwayan to Sabinian age. The overlying Williamsburg Formation probably represents deposits of cycle TA2.1. The superjacent siliciclastics of the Congaree Formation contain few fossils, but may preserve transgressive and highstand deposits of cycles TA2.4 - 3.3. The overlying unit is commonly calcareous, contains nannofossils indicative of zones NP16-17 (Upper Claibornian), and marks a significant change in depositional style subsequent to the 49.5 Ma eustatic fall. ''Marls'' of the overlying Griffins Landing Member of the Dry Branch Formation contain micro- and megafossils of Late Eocene (Jacksonian) age and represent transgressive deposits of cycle TA4.1. The discontinuous lateral distribution of these calcareous units and overlying clastics of the Dry Branch and Tobacco Road Formations results largely from erosion and deep incision during the mid-Oligocene eustatic fall (30 Ma). The ''Upland'' unit is interpreted as being deposited on this erosional surface.

  2. Greenhouse gas fluxes in southeastern U.S. coastal plain wetlands under contrasting land uses.

    PubMed

    Morse, Jennifer L; Ardón, Marcelo; Bernhardt, Emily S

    2012-01-01

    Whether through sea level rise or wetland restoration, agricultural soils in coastal areas will be inundated at increasing rates, renewing connections to sensitive surface waters and raising critical questions about environmental trade-offs. Wetland restoration is often implemented in agricultural catchments to improve water quality through nutrient removal. Yet flooding of soils can also increase production of the greenhouse gases nitrous oxide and methane, representing a potential environmental trade-off. Our study aimed to quantify and compare greenhouse gas emissions from unmanaged and restored forested wetlands, as well as actively managed agricultural fields within the North Carolina coastal plain, USA. In sampling conducted once every two months over a two-year comparative study, we found that soil carbon dioxide flux (range: 8000-64 800 kg CO2 x ha(-1) x yr(-1)) comprised 66-100% of total greenhouse gas emissions from all sites and that methane emissions (range: -6.87 to 197 kg CH4 x ha(-1) x yr(-1)) were highest from permanently inundated sites, while nitrous oxide fluxes (range: -1.07 to 139 kg N2O x ha(-1) x yr(-1)) were highest in sites with lower water tables. Contrary to predictions, greenhouse gas fluxes (as CO2 equivalents) from the restored wetland were lower than from either agricultural fields or unmanaged forested wetlands. In these acidic coastal freshwater ecosystems, the conversion of agricultural fields to flooded young forested wetlands did not result in increases in greenhouse gas emissions.

  3. Groundwater freshening following coastal progradation and land reclamation of the Po Plain, Italy

    NASA Astrophysics Data System (ADS)

    Antonellini, M.; Allen, D. M.; Mollema, P. N.; Capo, D.; Greggio, N.

    2015-08-01

    Many coastal areas historically were inundated by seawater, but have since undergone land reclamation to enable settlements and farming. This study focuses on the coastal unconfined aquifer in the Po Plain near Ravenna, Italy. Freshwater is present as isolated thin (1-5 m) lenses on top of brackish to saline water. Historical maps show large areas of sea inundation until approximately 150-200 years ago when coastal progradation and construction of the drainage canals began. Since then, the aquifer has been freshening from recharge. A three-dimensional SEAWAT model is used to simulate a 200-year freshening history, starting with a model domain that is saturated with seawater, and applying recharge across the top model layer. Calibration to the observed concentrations for discrete depths within many monitoring wells is remarkably good. The current distribution of freshwater is largely controlled by the drainage network. Within and adjacent to the drains, the groundwater has high salinity due to up-coning of salt water. Between drains, the surface layers of the aquifer are fresh due to the flushing action of recharge. The modeling results are consistent with cation exchange processes revealed in the groundwater chemistry and with freshwater lenses identified in electrical resistivity soundings.

  4. Socioeconomic factors, attitudes and practices associated with malaria prevention in the coastal plain of Chiapas, Mexico

    PubMed Central

    2014-01-01

    Background Mexico is in the malaria pre-elimination phase; therefore, continuous assessment and understanding of the social and behavioural risk factors related to exposure to malaria are necessary to achieve the overall goal. The aim of this research was to investigate socio-economic backgrounds, attitudes and practices related with malaria in rural locations from the coastal plain of Chiapas. Methods In January 2012, 542 interviews were conducted to householders from 20 villages across the coastal plain of Chiapas. Questions were about housing conditions, protection from mosquito bites and general information of householders. Chi2 analyses were performed to see whether there was a dependence of those reported having malaria with their house conditions and their malaria preventive practices. Results were discussed and also compared statistically against those obtained 17 years ago from the same area. Results Most households had 2–5 people (73.6%), 91.6% of houses had 1–3 bedrooms. The physical structure of the houses consisted of walls mainly made of block or brick 72.3%, the floor made of cement 90.0%, while the roof made of zinc sheet 43.9%, and straw or palm 42.2%. A 23.1% of the interviewed completed elementary school and 16.6% was illiterate. A 9.9% of the residents reported at least one family member having had malaria. A 98.1% of families used some method to prevent mosquito bites; those using bed nets were 94.3%. Almost 72% of families bought products for mosquito protection. A total of 537 out of 542 families agreed with the indoor residual spraying (IRS) of insecticide and a frequency of application as often as every two months was preferred. Conclusion Housing conditions and malaria preventive practices have improved in these rural areas in 17 years, which could be in favor of malaria elimination in this area. Information generated by this study could help in the decision making about whether to use insecticide as indoor residual spraying or to

  5. Comparison of soil amendments to decrease high strength in SE USA Coastal Plain soils using fuzzy decision-making analyses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cemented subsurface layers restrict root growth in many southeastern USA Coastal Plain soils. Though cementation is usually reduced by tillage, soil amendments can offer a more permanent solution if they develop aggregation. To increase aggregation, we amended 450 g of a Norfolk soil blend of 90% E ...

  6. Late Cenozoic marine deposition in the United States Atlantic Coastal Plain related to tectonism and global climate

    USGS Publications Warehouse

    Blackwelder, B. W.

    1981-01-01

    Major hiatuses in upper Cenozoic marine deposits in the United States Atlantic Coastal Plain are recognized on the basis of molluscan faunal changes at erosional unconformities. These hiatuses generally coincided with periods of global cooling and ice sheet formation. Such hiatuses provide information to supplement global climatic data. Major hiatuses are recognized within the early Miocene (23-20 m.y. ago), at the end of the middle Miocene (??? 11-10 m.y. ago), at the end of the late Miocene (???6.5-5 m.y. ago), at the end of the early Pliocene (???4.0-2.5 m.y. ago), at the end of the late Pliocene (???1.9 or 1.8 m.y. ago), within the Pleistocene (???1.1-0.5 m.y. ago) and several times within the last 0.4 m.y. Estimates of the amount of water contained in ice sheets at different times in the Pliocene and Pleistocene facilitate calculation of probable minimum sea levels on the Coastal Plain during different high stands of the sea. The altitudes of dated shoreline deposits in the Atlantic Coastal Plain show that the amount of uplift in the Cape Fear area has averaged at least 1.3 cm per 1000 years since the beginning of Pliocene time. The Coastal Plain of Georgia has apparently experienced relatively little vertical deformation during this same time. ?? 1981.

  7. 50 CFR Appendix I to Part 37 - Legal Description of the Coastal Plain, Arctic National Wildlife Refuge, Alaska

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., Arctic National Wildlife Refuge, Alaska I Appendix I to Part 37 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM GEOLOGICAL AND GEOPHYSICAL EXPLORATION OF THE COASTAL PLAIN, ARCTIC NATIONAL WILDLIFE REFUGE, ALASKA Pt....

  8. 50 CFR Appendix I to Part 37 - Legal Description of the Coastal Plain, Arctic National Wildlife Refuge, Alaska

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., Arctic National Wildlife Refuge, Alaska I Appendix I to Part 37 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM GEOLOGICAL AND GEOPHYSICAL EXPLORATION OF THE COASTAL PLAIN, ARCTIC NATIONAL WILDLIFE REFUGE, ALASKA Pt....

  9. Ameliorating soil chemical properties of a hard setting subsoil layer in coastal plain USA with different designer biochars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Norfolk soils in the southeastern United States of America (USA) Coastal Plain region have meager soil fertility characteristics because of their sandy textures, acidic pH values, kaolinitic clays and with depleted organic carbon contents. Extensive clay mineral weathering and clay eluviation along ...

  10. Soil carbon sequestration with continuous no-till management of grain cropping systems in the Virginia coastal plain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbon sequestration in agroecosystems represents a significant opportunity to offset a portion of anthropogenic CO2 emissions. Climatic conditions in the Virginia coastal plain and modern production practices make it possible for high annual photosynthetic CO2 fixation. There is potential to seques...

  11. The Estimated Likelihood of Nutrients and Pesticides in Nontidal Headwater Streams of the Maryland Coastal Plain During Base Flow

    EPA Science Inventory

    Water quality in nontidal headwater (first-order) streams of the Coastal Plain during base flow in the late winter and spring is related to land use, hydrogeology, and other natural or human influences in contributing watersheds. A random survey of 174 headwater streams of the Mi...

  12. An integrated system of summer solarization and fallow tillage for Cyperus esculentus and nematode management in the southeastern coastal plain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solarization is a form of pest control using clear plastic mulch that allows sunlight to heat the soil to temperatures lethal to plant pests. Fallow tillage is a proven practice to reduce baseline weed densities. Field trials were conducted at the Coastal Plain Experiment Station in Tifton, GA fro...

  13. Water levels in major artesian aquifers of the New Jersey Coastal Plain, 1983

    USGS Publications Warehouse

    Eckel, J.A.; Walker, R.L.

    1986-01-01

    Water levels and changes in water levels in the major aquifers of the New Jersey Coastal Plain are documented. Water levels in 1,071 wells were measured in 1983, and are compared with 827 water level measurements made in the same wells in 1978. Increased groundwater withdrawals from the major artesian aquifers that underlie the New Jersey Coastal Plain have caused large cones of depression in the artesian heads. These cones are delineated on detailed potentiometric surface maps based on water level data collected in the fall of 1983. Hydrographs from observation wells show trends of water levels for the 6-year period of 1978 through 1983. The Potomac-Raritan-Magothy aquifer system is divided into the lower, middle, and upper aquifers. The potentiometric surfaces in these aquifers form large cones of depression centered in the Camden and Middlesex-Monmouth County areas. Measured water levels declined as much as 23 ft in these areas for the period of study. The lowest levels are 96 ft below sea level in Camden County and 91 ft below sea level in the Middlesex-Monmouth County area. Deep cones of depression in coastal Monmouth and Ocean counties in both the Englishtown aquifer system and Wenonah-Mount Laurel aquifer are similar in location and shape. This is because of an effective hydraulic connection between these aquifers. Measured water levels declined as much as 29 ft in the Englishtown aquifer system and 21 ft in the Wenonah-Mount Laurel aquifer during the period of study. The lowest levels are 249 ft below sea level in the Englishtown aquifer system and 196 ft below sea level in the Wenonah-Mount Laurel aquifer. Water levels in the Piney Point aquifer are as low as 75 ft below sea level at Seaside Park, Ocean County and 35 ft below sea level in southern Cumberland County. Water levels in Cumberland County are affected by large withdrawals of groundwater in Kent County, Delaware. Water levels in the Atlantic City 800 ft sand of the Kirkwood Formation define an

  14. Estimation of Dust Emission from the Western Coastal Plains of Arabian Peninsula

    NASA Astrophysics Data System (ADS)

    Anisimov, Anatolii; Stenchikov, Georgiy

    2016-04-01

    This study is aimed at quantifying local-scale dust emission from the coastal areas of western Arabian Peninsula. The dust emitted from these areas is frequently deposited directly to the Red Sea, acting as an important component of the nutrient balance of marine ecosystems. Most chemicals including iron, phosphorus, and nitrogen are introduced to the Red Sea with airborne dust. This process is especially significant for the oligotrophic northern Red Sea, where nutrients from the Indian Ocean cannot reach and the nutrient supply from land river discharge is negligible. The dust deposition to the Red Sea associated with major dust storms was recently estimated to be about 6 Tg/yr, but this estimate does not account for local, small-scale dust outbreaks occurring during fair weather conditions or moderate winds. The seasonality and the magnitude of this nutrient supply are largely unknown. In the present study, we quantify dust emissions using the fine-scale off-line version-4 of the Community Land Model (CLM4) with the high-resolution datasets as input parameters. We examine the model sensitivity to the spatial resolution of input land cover and vegetation data, and compare the results with weather station observations and reanalysis to choose the best model configuration. The model results are shown to be in reasonable agreement with station visibility measurements and the frequency of dust event reports. To improve the spatial characteristics of dust emission, we apply two state-of-the-art dust source functions. We found that the source function based on measurements from SEVIRI satellite substantially improves the simulation results, being in good agreement with both reanalysis data and station measurements. We identify the major dust source hot-spot areas over the coastal plain and analyze the seasonal and diurnal variability of dust emissions. The annual dust generation from the 145000 km2 coastal area reaches 6 Tg/yr. Roughly half of emitted dust could be

  15. Intermittent Elevated Radium Concentrations in Coastal Plain Groundwater of South Carolina, U.S.A.

    SciTech Connect

    Denham, Miles; Millings, Margaret; Noonkester, Jay

    2005-09-22

    To learn the cause of intermittent radium concentrations in groundwater of Coastal Plain aquifers, 31 groundwater wells in South Carolina, U.S.A. were sampled for radium and other geochemical parameters. Sediments cored from near the well screens were also sampled to examine any relationship between sediment properties and radium concentration in the groundwater. Elevated radium concentrations only occurred in groundwater with low electrical conductivity and pH values below 6.3. The adsorption edge for radium on hematite--a major surface active mineral in these aquifers--is at a pH value of about 6. Near this value, small changes in pH can result in significant adsorption or desorption of radium. In groundwater with initially low alkalinity, small intermittent decreases in partial pressure of carbon dioxide in groundwater cause decreases in pH and desorption of radium. The result is intermittent elevated radium concentrations.

  16. Nomenclature of regional hydrogeologic units of the Southeastern Coastal Plain aquifer system

    USGS Publications Warehouse

    Miller, J.A.; Renken, R.A.

    1988-01-01

    Clastic sediments of the Southeastern Coastal Plain aquifer system can be divided into four regional aquifers separated by three regional confining units. The four regional aquifers have been named for major rivers that cut across their outcrop areas and expose the aquifer materials. From youngest to oldest, the aquifers are called the Chickasawhay River, Pearl River, Chattahoochee River, and Black Warrior River aquifers, and the regional confining units separating them are given the same name as the aquifer they overlie. Most of the regional hydrogeologic units are subdivided within each of the four States that comprise the study area. Correlation of regional units is good with hydrogeologic units delineated by a similar regional study to the west and southwest. Because of complexity created by a major geologic structure to the northeast of the study area and dramatic facies change from clastic to carbonate strata to the southeast, correlation of regional hydrogeologic units is poor in these directions. (Author 's abstract)

  17. Magmatic history of Red Sea rifting: perspective from the central Saudi Arabian coastal plain.

    USGS Publications Warehouse

    Pallister, J.S.

    1987-01-01

    An early stage of magmatism related to Red Sea rifting is recorded by a Tertiary dyke complex and comagmatic volcanic rocks exposed on the central Saudi Arabian coastal plain. Field relations and new K/Ar dates indicate episodic magmatism from approx 30 m.y. to the present day and rift-related magmatism as early as 50 m.y. Localized volcanism and sheeted dyke injection ceased at approx 20 m.y. and were replaced by the intrusion of thick gabbro dykes, marking the onset of sea-floor spreading in the central Red Sea. Differences in the depths and dynamics of mantle-melt extraction and transport may account for the transition from mixed alkaline-subalkaline bimodal magmatism of the pre-20 m.y. rift basin to exclusively subalkaline (tholeiitic) magmatism of the Red Sea spreading axis and the alkali basalt volcanism inland.-L.C.H.

  18. The hydrogeologic framework for the southeastern Coastal Plain aquifer system of the United States

    USGS Publications Warehouse

    Renken, R.A.

    1984-01-01

    Tertiary and Cretaceous age sand aquifers of the southeastern United States Coastal Plain constitute a distinct multistate hydrogeologic regime informally defined as the southeastern sand aquifer. Seven regional hydrogeologic units are defined; four regional aquifer units and three regional confining beds. Sand aquifers of this system consist of quartzose, feldspathic, and coarse to fine sand and sandstone and minor limestone; confining beds are composed of clay, shale, chalk, and marl. Three hydrogeologic units of Cretaceous to Holocene age overlie the sand system: the surficial aquifer, upper confining unit, and Floridan aquifer system. These three units are not part of the southeastern sand aquifer, but are an integral element of the total hydrogeologic system, and some act as a source of recharge to, or discharge from the underlying clastic sediments. Low-permeability strata of Paleozoic to early Mesozoic age form the base off the total system. (USGS)

  19. Simulation of Groundwater Flow in the Coastal Plain Aquifer System of Virginia

    USGS Publications Warehouse

    Heywood, Charles E.; Pope, Jason P.

    2009-01-01

    The groundwater model documented in this report simulates the transient evolution of water levels in the aquifers and confining units of the Virginia Coastal Plain and adjacent portions of Maryland and North Carolina since 1890. Groundwater withdrawals have lowered water levels in Virginia Coastal Plain aquifers and have resulted in drawdown in the Potomac aquifer exceeding 200 feet in some areas. The discovery of the Chesapeake Bay impact crater and a revised conceptualization of the Potomac aquifer are two major changes to the hydrogeologic framework that have been incorporated into the groundwater model. The spatial scale of the model was selected on the basis of the primary function of the model of assessing the regional water-level responses of the confined aquifers beneath the Coastal Plain. The local horizontal groundwater flow through the surficial aquifer is not intended to be accurately simulated. Representation of recharge, evapotranspiration, and interaction with surface-water features, such as major rivers, lakes, the Chesapeake Bay, and the Atlantic Ocean, enable simulation of shallow flow-system details that influence locations of recharge to and discharge from the deeper confined flow system. The increased density of groundwater associated with the transition from fresh to salty groundwater near the Atlantic Ocean affects regional groundwater flow and was simulated with the Variable Density Flow Process of SEAWAT (a U.S. Geological Survey program for simulation of three-dimensional variable-density groundwater flow and transport). The groundwater density distribution was generated by a separate 108,000-year simulation of Pleistocene freshwater flushing around the Chesapeake Bay impact crater during transient sea-level changes. Specified-flux boundaries simulate increasing groundwater underflow out of the model domain into Maryland and minor underflow from the Piedmont Province into the model domain. Reported withdrawals accounted for approximately

  20. The Chesapeake Bay bolide impact: A convulsive event in Atlantic Coastal Plain evolution

    USGS Publications Warehouse

    Poag, C.W.

    1997-01-01

    Until recently, Cenozoic evolution of the Atlantic Coastal Plain has been viewed as a subcyclical continuum of deposition and erosion. Marine transgressions alternated with regressions on a slowly subsiding passive continental margin, their orderly succession modified mainly by isostatic adjustments, occasional Appalachian tectonism, and paleoclimatic change. This passive scenario was dramatically transformed in the late Eocene, however, by a bolide impact on the inner continental shelf. The resultant crater is now buried 400-500 m beneath lower Chesapeake Bay, its surrounding peninsulas, and the continental shelf east of Delmarva Peninsula. This convulsive event, and the giant tsunami it engendered, fundamentally changed the regional geological framework and depositional regime of the Virginia Coastal Plain, and produced the following principal consequences. (1) The impact excavated a roughly circular crater, twice the size of Rhode Island (???6400 km2) and nearly as deep as the Grand Canyon (???1.3 km deep). (2) The excavation truncated all existing ground-water aquifers in the target area by gouging ???4300 km3 of rock from the upper lithosphere, including Proterozoic and Paleozoic crystalline basement rocks and Middle Jurassic to upper Eocene sedimentary rocks. (3) Synimpact depositional processes, including ejecta fallback, massive crater-wall failure, water-column collapse, and tsunami backwash, filled the crater with a porous breccia lens, 600-1200 m thick, at a phenomenal rate of ???1200 m/hr. The breccia lens replaced the truncated ground-water aquifers with a single 4300 km3 reservoir, characterized by ground water ???1.5 times saltier than normal sea water (chlorinities as high as 25,700 mg/l). (4) A structural and topographic low, created by differential subsidence of the compacting breccia, persisted over the crater at least through the Pleistocene. In the depression are preserved postimpact marine lithofacies and biofacies (upper Eocene, lower

  1. Biostratigraphic implications of the first Eocene land-mammal fauna from the North American coastal plain

    NASA Astrophysics Data System (ADS)

    Westgate, James W.

    1988-11-01

    A newly discovered vertebrate fossil assemblage, the Casa Blanca local fauna, comes from the Laredo Formation, Claiborne Group, of Webb County, Texas, and is the first reported Eocene land-mammal fauna from the coastal plain of North America. The mammalian fauna is correlated with the Serendipity and Candelaria local faunas of west Texas, the Uinta C faunas of the Rocky Mountains, the Santiago Formation local fauna of southern California, and the Swift Current Creek local fauna of Saskatchewan. The vertebrate-bearing deposit lies about 32 m above a horizon containing the marine gastropod Turritella cortezi, which ranges from east Texas to northeast Mexico in the lower half of the Cook Mountain and Laredo Formations and is a guide fossil to the Hurricane Lentil in the Cook Mountain Formation. Nannoplankton found in these middle Eocene formations belong to the upper half of Nannoplankton Zone I6 and allow correlation with European beds of late Lutetian to early Bartonian age.

  2. Biostratigraphic implications of the first Eocene land-mammal fauna from the North American coastal plain

    SciTech Connect

    Westgate, J.W. )

    1988-11-01

    A newly discovered vertebrate fossil assemblage, the Casa Blanca local fauna, comes from the Laredo Formation, Claiborne Group, of Webb County, Texas, and is the first reported Eocene land-mammal fauna from the coastal plain of North America. The mammalian fauna is correlated with the Serendipity and Canderlaria local faunas of west Texas, the Uinta C faunas of the Rocky Mountains, the Santiago Formation local fauna of southern California, and the Swift Current Creek local fauna of Saskatchewan, The vertebrate-bearing deposit lies about 32 m above a horizon containing the marine gastropod Turritella cortezi, which ranges from east Texas to northeast Mexico in the lower half of the Cook Mountain and Laredo Formations and is a guide fossil to the Hurricane Lentil in the Cook Mountain Formation. Nannoplankton found in these middle Eocene formations belong to the upper half of Nannoplankton Zone 16 and allow correlation with European beds of late Lutetian to early Bartonian age.

  3. Past permafrost on the Mid-Atlantic coastal plain, eastern United States

    USGS Publications Warehouse

    French, H.; Demitroff, M.; Newell, W.L.

    2009-01-01

    Sand-wedge casts, soil wedges and other non-diastrophic, post-depositional sedimentary structures suggest that Late-Pleistocene permafrost and deep seasonal frost on the Mid-Atlantic Coastal Plain extended at least as far south as southern Delaware, the Eastern Shore and southern Maryland. Heterogeneous cold-climate slope deposits mantle lower valley-side slopes in central Maryland. A widespread pre-existing fragipan is congruent with the inferred palaeo-permafrost table. The high bulk density of the fragipan was probably enhanced by either thaw consolidation when icy permafrost degraded at the active layer-permafrost interface or by liquefaction and compaction when deep seasonal frost thawed. ?? 2009 John Wiley & Sons, Ltd.

  4. Salt-dome locations in the Gulf Coastal Plain, South-Central United States

    USGS Publications Warehouse

    Beckman, J.D.; Williamson, A.K.

    1990-01-01

    Information on salt domes in Gulf of Mexico Coastal Plain, south-central United States and the adjacent Continental Shelf were compiled from major published sources, 1973-84. The location of 624 salt domes is shown on a map at a scale of 1:1 ,500,000. A color-coding system was used to show that the occurrence, size, shape, and location of these domes varies among sources. Two tables of additional data accompany the map and include other available information such as: identifying sources, depth to salt and caprock, diameter, volume, name, and uppermost zone of surrounding sediment that is penetrated, as well as the number of matches between sources. The locations of salt domes that penetrate specific zones within the gulf coast regional aquifer system are shown on maps. (USGS)

  5. ERTS surveys a 500 km squared locust breeding site in Saudi Arabia. [Red Sea coastal plain

    NASA Technical Reports Server (NTRS)

    Pedgley, D. E.

    1974-01-01

    From September 1972 to January 1973, ERTS-1 precisely located a 500 sq km area on the Red Sea coastal plain of Saudi Arabia within which the Desert Locust (Schistocerca gregaria, Forsk.) bred successfully and produced many small swarms. Growth of vegetation shown by satellite imagery was confirmed from ground surveys and raingauge data. The experiment demonstrates the feasibility of detecting potential locust breeding sites by satellite, and shows that an operational satellite would be a powerful tool for routine survey of the 3 x 10 to the 7th power sq km invasion area of the Desert Locust in Africa and Asia, as well as of other locust species in the arid and semi-arid tropics.

  6. A Science Plan for a Comprehensive Regional Assessment of the Atlantic Coastal Plain Aquifer System in Maryland

    USGS Publications Warehouse

    Shedlock, Robert J.; Bolton, David W.; Cleaves, Emery T.; Gerhart, James M.; Nardi, Mark R.

    2007-01-01

    The Maryland Coastal Plain region is, at present, largely dependent upon ground water for its water supply. Decades of increasing pumpage have caused ground-water levels in parts of the Maryland Coastal Plain to decline by as much as 2 feet per year in some areas of southern Maryland. Continued declines at this rate could affect the long-term sustainability of ground-water resources in Maryland's heavily populated Coastal Plain communities and the agricultural industry of the Eastern Shore. In response to a recommendation in 2004 by the Advisory Committee on the Management and Protection of the State's Water Resources, the Maryland Geological Survey and the U.S. Geological Survey have developed a science plan for a comprehensive assessment that will provide new scientific information and new data management and analysis tools for the State to use in allocating ground water in the Coastal Plain. The comprehensive assessment has five goals aimed at improving the current information and tools used to understand the resource potential of the aquifer system: (1) document the geologic and hydrologic characteristics of the aquifer system in the Maryland Coastal Plain and appropriate areas of adjacent states; (2) conduct detailed studies of the regional ground-water-flow system and water budget for the aquifer system; (3) improve documentation of patterns of water quality in all Coastal Plain aquifers, including the distribution of saltwater; (4) enhance ground-water-level, streamflow, and water-quality-monitoring networks in the Maryland Coastal Plain; and (5) develop science-based tools to facilitate sound management of the ground-water resources in the Maryland Coastal Plain. The assessment, as designed, will be conducted in three phases and if fully implemented, is expected to take 7 to 8 years to complete. Phase I, which was initiated in January 2006, is an effort to assemble all the information and investigation tools needed to do a more comprehensive assessment of

  7. Characterizing mercury concentrations and fluxes in a Coastal Plain watershed: Insights from dynamic modeling and data

    USGS Publications Warehouse

    Golden, H.E.; Knightes, C.D.; Conrads, P.A.; Davis, G.M.; Feaster, T.D.; Journey, C.A.; Benedict, S.T.; Brigham, M.E.; Bradley, P.M.

    2012-01-01

    Mercury (Hg) is one of the leading water quality concerns in surface waters of the United States. Although watershed-scale Hg cycling research has increased in the past two decades, advances in modeling watershed Hg processes in diverse physiographic regions, spatial scales, and land cover types are needed. The goal of this study was to assess Hg cycling in a Coastal Plain system using concentrations and fluxes estimated by multiple watershed-scale models with distinct mathematical frameworks reflecting different system dynamics. We simulated total mercury (Hg T, the sum of filtered and particulate forms) concentrations and fluxes from a Coastal Plain watershed (McTier Creek) using three watershed Hg models and an empirical load model. Model output was compared with observed in-stream Hg T. We found that shallow subsurface flow is a potentially important transport mechanism of particulate Hg T during periods when connectivity between the uplands and surface waters is maximized. Other processes (e.g., stream bank erosion, sediment re-suspension) may increase particulate Hg T in the water column. Simulations and data suggest that variable source area (VSA) flow and lack of rainfall interactions with surface soil horizons result in increased dissolved Hg T concentrations unrelated to DOC mobilization following precipitation events. Although flushing of DOC-Hg T complexes from surface soils can also occur during this period, DOC-complexed Hg T becomes more important during base flow conditions. TOPLOAD simulations highlight saturated subsurface flow as a primary driver of daily Hg T loadings, but shallow subsurface flow is important for Hg T loads during high-flow events. Results suggest limited seasonal trends in Hg T dynamics. Copyright 2012 by the American Geophysical Union.

  8. Characterizing mercury concentrations and fluxes in a Coastal Plain watershed: Insights from dynamic modeling and data

    USGS Publications Warehouse

    Golden, H.E.; Knightes, C.D.; Conrads, P.A.; Davis, G.M.; Feaster, T.D.; Journey, C.A.; Benedict, S.T.; Brigham, M.E.; Bradley, P.M.

    2012-01-01

    Mercury (Hg) is one of the leading water quality concerns in surface waters of the United States. Although watershed-scale Hg cycling research has increased in the past two decades, advances in modeling watershed Hg processes in diverse physiographic regions, spatial scales, and land cover types are needed. The goal of this study was to assess Hg cycling in a Coastal Plain system using concentrations and fluxes estimated by multiple watershed-scale models with distinct mathematical frameworks reflecting different system dynamics. We simulated total mercury (HgT, the sum of filtered and particulate forms) concentrations and fluxes from a Coastal Plain watershed (McTier Creek) using three watershed Hg models and an empirical load model. Model output was compared with observed in-stream HgT. We found that shallow subsurface flow is a potentially important transport mechanism of particulate HgT during periods when connectivity between the uplands and surface waters is maximized. Other processes (e.g., stream bank erosion, sediment re-suspension) may increase particulate HgT in the water column. Simulations and data suggest that variable source area (VSA) flow and lack of rainfall interactions with surface soil horizons result in increased dissolved HgT concentrations unrelated to DOC mobilization following precipitation events. Although flushing of DOC-HgT complexes from surface soils can also occur during this period, DOC-complexed HgT becomes more important during base flow conditions. TOPLOAD simulations highlight saturated subsurface flow as a primary driver of daily HgT loadings, but shallow subsurface flow is important for HgT loads during high-flow events. Results suggest limited seasonal trends in HgT dynamics.

  9. Water Levels In Major Artesian Aquifers Of The New Jersey Coastal Plain, 1988

    USGS Publications Warehouse

    Rosman, Robert; Lacombe, Pierre J.; Storck, Donald A.

    1995-01-01

    Water levels in 1,251 wells in the New Jersey Coastal Plain, Philadelphia County, Pennsylvania, and Kent and New Castle Counties, Delaware, were measured from October 1988 to February 1989 and compared with 1,071 water levels measured from September 1983 to May 1984. Water levels in 916 of the wells measured in the 1983 study were remeasured in the 1988 study. Alternate wells were selected to replace wells used in 1983 that were inaccessible at the time of the water-level measurements in 1988 or had been destroyed. New well sites were added in strategic locations to increase coverage where possible. Large cones of depression have formed or expanded in the nine major artesian aquifers that underlie the New Jersey Coastal Plain. Water levels are shown on nine potentiometric-surface maps. Hydrographs for observation wells typically show water-level declines for 1983, through 1989. In the confined Cohansey aquifer, the lowest water level, 20 feet below sea level, was measured in a well located at Cape May City Water Department, Cape May County. Water levels in the Atlantic City 800-foot sand declined as much as 21 feet at Ventnor, Atlantic County, over the 6-year period from the 1983 study to this study for 1988. Water levels in the Piney Point aquifer were as low as 56 feet below sea level at Seaside Park, Ocean County; 45 feet below sea level in southern Cumberland County; and 28 feet below sea level at Margate, Atlantic County. Water levels in the Vincentown aquifer did not change over the 6-year period. The lowest water levels in the Wenonah-Mount Laurel aquifer and the Englishtown aquifer system were 218 feet and 256 feet below sea level, respectively. Large cones of depression in the Potomac- Raritan-Magothy aquifer system are centered in the Camden County area and the Middlesex and Monmouth County area. Water levels declined as much as 46 feet in these areas over the 6-year period.

  10. Mitigation bank promotes research on restoring Coastal Plain depression wetlands (South Carolina).

    SciTech Connect

    Barton, Christopher D.; DeSteven, Diane; Kilgo, John C.

    2004-12-31

    Barton, Christopher, D., Diane DeSteven and John C. Kilgo. 2004. Mitigation bank promotes research on restoring Coastal Plain depression wetlands (South Carolina). Ecol. Rest. 22(4):291-292. Abstract: Carolina bays and smaller depression wetlands support diverse plant communities and provide critical habitat for semi-aquatic fauna throughout the Coastal Plain region of the southeastern United States. Historically, many depression wetlands were altered or destroyed by surface ditching, drainage, and agricultural or silviculture uses. These important habitats are now at further risk of alteration and loss following a U.S. Supreme Court decision in 2001 restricting federal regulation of isolated wetlands. Thus, there is increased attention towards protecting intact sites and developing methods to restore others. The U.S. Department of Energy's (DOE) 312-mi2 (800-km2) Savannah River Site (SRS) in west-central South Carolina includes about 350 Carolina bays and bay-like wetland depressions, of which about two-thirds were degraded or destroyed prior to federal acquisition of the land. Although some of the altered wetlands have recovered naturally, others still have active active drainage ditches and contain successional forests typical of drained sites. In 1997, DOE established a wetland mitigation bank to compensate for unavoidable wetland impacts on the SRS. This effort provided an opportunity fir a systematic research program to investigate wetland restoration techniques and ecological responses. Consequently, research and management staffs from the USDA Forest Service, Westinghouse Savannah River Corporation, the Savannah River Technology Center, the Savannah River Ecology Laboratory (SREL) and several universities developed a collaborative project to restore degraded depression wetlands on the SRS. The mitigation project seeks cost-effective methods to restore the hydrology and vegetation typical of natural depression wetlands, and so enhance habitats for wetland

  11. Characterizing mercury concentrations and fluxes in a Coastal Plain watershed: Insights from dynamic modeling and data

    NASA Astrophysics Data System (ADS)

    Golden, H. E.; Knightes, C. D.; Conrads, P. A.; Davis, G. M.; Feaster, T. D.; Journey, C. A.; Benedict, S. T.; Brigham, M. E.; Bradley, P. M.

    2012-03-01

    Mercury (Hg) is one of the leading water quality concerns in surface waters of the United States. Although watershed-scale Hg cycling research has increased in the past two decades, advances in modeling watershed Hg processes in diverse physiographic regions, spatial scales, and land cover types are needed. The goal of this study was to assess Hg cycling in a Coastal Plain system using concentrations and fluxes estimated by multiple watershed-scale models with distinct mathematical frameworks reflecting different system dynamics. We simulated total mercury (HgT, the sum of filtered and particulate forms) concentrations and fluxes from a Coastal Plain watershed (McTier Creek) using three watershed Hg models and an empirical load model. Model output was compared with observed in-stream HgT. We found that shallow subsurface flow is a potentially important transport mechanism of particulate HgTduring periods when connectivity between the uplands and surface waters is maximized. Other processes (e.g., stream bank erosion, sediment re-suspension) may increase particulate HgT in the water column. Simulations and data suggest that variable source area (VSA) flow and lack of rainfall interactions with surface soil horizons result in increased dissolved HgTconcentrations unrelated to DOC mobilization following precipitation events. Although flushing of DOC-HgTcomplexes from surface soils can also occur during this period, DOC-complexed HgT becomes more important during base flow conditions. TOPLOAD simulations highlight saturated subsurface flow as a primary driver of daily HgT loadings, but shallow subsurface flow is important for HgTloads during high-flow events. Results suggest limited seasonal trends in HgT dynamics.

  12. Upper Maastrichtian ammonite biostratigraphy of the Gulf Coastal Plain (Mississippi Embayment, southern USA)

    USGS Publications Warehouse

    Larina, Ekaterina; Garb, Matthew P.; Landman, Neil H.; Dastas, Natalie; Thibault, Nicolas; Edwards, Lucy E.; Phillips, George; Rovelli, Remy; Myers, Corinne; Naujokaityte, Jone

    2016-01-01

    The Cretaceous outcrop belt of the Mississippi Embayment in the Gulf Coastal Plain (GCP) spans the Cretaceous/Paleogene (K/Pg) boundary. A detailed reconstruction of this time interval is critical for understanding the nature of biotic and environmental changes preceding the end-Cretaceous Mass Extinction event and for deciphering the likely extinction mechanism (i.e., bolide impact versus volcanism). Eight sections encompassing the K/Pg succession across the Mississippi Embayment were analyzed using biostratigraphic sampling of ammonites, dinoflagellates, and nannofossils. An upper Maastrichtian ammonite zonation is proposed as follows, from oldest to youngest:Discoscaphites conradi Zone, D. minardi Zone, and D. iris Zone. Our study documents that the ammonite zonation established in the Atlantic Coastal Plain (ACP) extends to the GCP. This zonation is integrated with nannofossil and dinoflagellate biostratigraphy to provide a framework to more accurately determine the age relationships in this region. We demonstrate that ammonites and dinoflagellates are more reliable stratigraphic indicators in this area than nannofossils because age-diagnostic nannofossils are not consistently present within the upper Maastrichtian in the GCP. This biostratigraphic framework has the potential to become a useful tool for correlation of strata both within the GCP and between the GCP, Western Interior, and ACP. The presence of the uppermost Maastrichtian ammonite D. iris, calcareous nannofossil Micula prinsii, and dinoflagellates Palynodinium grallator and Disphaerogena carposphaeropsis suggests that the K/Pg succession in the GCP is nearly complete. Consequently, the GCP is an excellent setting for investigating fine scale temporal changes across the K/Pg boundary and ultimately elucidating the mechanisms causing extinction.

  13. Storm-event flow pathways in lower coastal plain forested watersheds of the southeastern United States

    NASA Astrophysics Data System (ADS)

    Griffin, Michael P.; Callahan, Timothy J.; Vulava, Vijay M.; Williams, Thomas M.

    2014-10-01

    The landscape of the coastal plain of the southeastern United States is rapidly changing due to urbanization and climate-change-related impacts. In addition to the forecasted population increase, this region could experience significant changes in precipitation patterns making watershed management very challenging. In order to establish baseline data, storm-event flow pathways were studied in three lower coastal plain (LCP) forested lowland watersheds of the southeastern United States between 2010 and 2011. Two of the watersheds had clay loam subsoils while the third had sandy soils throughout the profile. Stream flow and water samples from water-table wells, piezometers, lysimeters, and rain gauges were analyzed for ion concentrations; ion trends were assessed using principal components analysis; and chemical hydrograph separation was performed for nine storm events using end-member mixing analysis. End-members consisted of lower concentration rainwater; a near-stream source (riparian or streambed groundwater); and a distant or deep groundwater source. Storm-event stream water on the clayey sites was composed primarily of rainwater (45-67% by volume) and shallow groundwater (21-55%), with small inputs from deep (below the clay-rich soil horizon) groundwater (0.2-21%). At the sandy site, a greater proportion was groundwater (56-61%), with smaller inputs from rainwater (28-33%) and soil water (6-16%). Dry antecedent soil moisture (ASM) conditions and larger storms resulted in greater rainwater contribution at the clayey sites. Shallow groundwater was an important contributor even in dry ASM conditions, perhaps due to the high specific retention of the soils. The results from this study will inform researchers about stormwater routing in forested, shallow water table watersheds and provide land managers with baseline data as they plan stormwater mitigation practices.

  14. Jurassic sequence stratigraphy of the eastern Gulf Coastal Plain: Applications to hydrocarbon exploration

    SciTech Connect

    Tew, B.H.; Mancini, E.A.; Mink, R.M. )

    1991-03-01

    Based on regional stratigraphic and sedimentologic data, three unconformity-bounded depositional sequences associated with cycles of relative sea-level change and coastal onlap are recognized for Jurassic strata in the eastern Gulf Coastal Plain area. These sequences are designated, in ascending order, the LZAGC (Lower Zuni A Gulf Coast)-3.1, the LZAGC-4.1, and the LZAGC-4.2 sequences and include Callovian through Kimmeridgian Stage strata. An understanding of the relationship of Jurassic reservoirs to sequence stratigraphy can serve as an aid to hydrocarbon exploration in the eastern gulf area. The most extensive and productive Jurassic hydrocarbon reservoirs in the study area occur within the progradational, regressive highstand deposits of the LZAGC-3.1 and LZAGC-4.1 depositional sequences. For example, the majority of Norphlet sandstone reservoirs in the onshore and offshore Alabama area are interpreted to have accumulated in eolian dune, interdune, and wadi (fluvial) depositional environments, which occurred in association with the highstand regressive system of the LZAGC-3.1 sequence. The most important Smackover reservoirs generally consist of partially to completely dolomitized ooid and peloid packstones and grainstones in the upper portion of the unit. These reservoirs occur in subtidal to supratidal, shoaling-upward carbonate mudstone to grainstone cycles in the highstand regressive system of the LZAGC-4.1 sequence. In addition, minor reservoirs that are discontinuous and not well developed are associated with the shelf margin and transgressive systems of the LZAGC-4.1.

  15. Ecology of tundra ponds of the Arctic Coastal Plain: a community profile

    SciTech Connect

    Hobbie, J.E.

    1984-06-01

    The Arctic Coastal Plain is a flat or gently rolling area of tundra which covers the entire coastal region of northern Alaska. This profile synthesizes data on the ecology of the thousands of small shallow ponds that form an important wetland community on the tundra. These polygonal ponds are formed by the freezing, thawing, and cracking of the perma-frost. Nutrient concentrations and rates of supply to the water column are controlled by interactions with the iron-rich peat sediments. Iron concentrations control phosphorus concentrations and these in turn control the growth of algae. Two fringing emergent vascular plants, Carex and Arctophila, are often the most important primary producers in the ponds. Most algae and higher plant biomass is decomposed by microbes in a detrital food web concentrated in the pond sediments. Chironomid larvae, oligochaete worms and other insects are the dominant benthic animals. Because the ponds freeze to the bottom each winter they contain no fish; however, the community is important for many species of migratory waterfowl and shorebirds that use the ponds for feeding and breeding. Activities associated with oil production, including spills, roads, and off-road vehicles, are the major issues facing managers of this wetland community. 63 references.

  16. Aminostratigraphy of surface and subsurface Quaternary sediments, North Carolina coastal plain, USA

    USGS Publications Warehouse

    Wehmiller, J. F.; Thieler, E.R.; Miller, D.; Pellerito, V.; Bakeman, Keeney V.; Riggs, S.R.; Culver, S.; Mallinson, D.; Farrell, K.M.; York, L.L.; Pierson, J.; Parham, P.R.

    2010-01-01

    The Quaternary stratigraphy and geochronology of the Albemarle Embayment of the North Carolina (NC) Coastal Plain is examined using amino acid racemization (AAR) in marine mollusks, in combination with geophysical, lithologic, and biostratigraphic analysis of 28 rotasonic cores drilled between 2002 and 2006. The Albemarle Embayment is bounded by structural highs to the north and south, and Quaternary strata thin westward toward the Suffolk paleoshoreline, frequently referred to as the Suffolk Scarp. The Quaternary section is up to ???90. m thick, consists of a variety of estuarine, shelf, back-barrier, and lagoonal deposits, and has been influenced by multiple sea-level cycles. The temporal resolution of the amino acid racemization method is tested statistically and with the stratigraphic control provided by this geologic framework, and it is then applied to the correlation and age estimation of subsurface units throughout the region. Over 500 specimens (primarily Mercenaria and Mulinia) from the subsurface section have been analyzed using either gas chromatographic (GC) or reverse-phase liquid chromatographic (RPLC) techniques. The subsurface stratigraphic data are compared with AAR results from numerous natural or excavated exposures from the surrounding region, as well as results from NC beach collections, to develop a comprehensive aminostratigraphic database for the entire Quaternary record within the NC coastal system. Age mixing, recognized in the beach collections, is also seen in subsurface sections, usually where major seismic reflections or core lithology indicate the presence of stratigraphic discontinuities. Kinetic models for racemization are tested within the regional stratigraphic framework, using either radiocarbon or U-series calibrations or comparison with regional biostratigraphy. Three major Pleistocene aminozones [AZ2, AZ3, and AZ4] are found throughout the region, all being found in superposition in several cores. Each can be subdivided

  17. Greenhouse Gas Fluxes in Southeastern US Coastal Plain Wetlands Under Contrasting Land Uses

    NASA Astrophysics Data System (ADS)

    Morse, J. L.; Ardón, M.; Bernhardt, E. S.

    2010-12-01

    Whether through sea level rise or wetland restoration, agricultural soils in coastal areas will be inundated at increasing rates, renewing connections to sensitive surface waters and raising critical questions about environmental tradeoffs. Wetland restoration is often implemented in agricultural catchments to improve water quality through nutrient removal. Yet higher soil moisture or flooding of soils can also increase the production of the greenhouse gases nitrous oxide and methane, representing a potential environmental tradeoff. Our study aimed to quantify and compare greenhouse gas emissions from natural and restored wetlands as well as actively managed agricultural fields within the NC coastal plain. In bimonthly sampling conducted over a two-year comparative study, we found that carbon dioxide was the dominant source (66-100%) of total emissions from all sites; that methane emissions were highest from permanently inundated sites, while nitrous oxide was a larger contributor to the radiative balance than methane for sites with lower water tables. In contrast to our predictions, greenhouse gas fluxes in the restored wetland were not higher compared to agricultural soils or forested wetlands. In these acidic coastal freshwater ecosystems, methane emissions tended to be low while nitrous oxide emissions tended to be high, relative to reported values for natural wetlands, suggesting that nitrogen loading or edaphic conditions in these systems may be promoting denitrification and nitrification as nitrous oxide sources while suppressing methanogenesis. Mean GHG fluxes (± standard error) and CO2 equivalents by site: agricultural field (Ag), restored wetland (RW) with 3 hydrologic classes, and two forested wetland sites (PA, PP). Different letters indicate statistical differences between sites (p < 0.1).

  18. Numerical simulation of groundwater flow in Dar es Salaam Coastal Plain (Tanzania)

    NASA Astrophysics Data System (ADS)

    Luciani, Giulia; Sappa, Giuseppe; Cella, Antonella

    2016-04-01

    They are presented the results of a groundwater modeling study on the Coastal Aquifer of Dar es Salaam (Tanzania). Dar es Salaam is one of the fastest-growing coastal cities in Sub-Saharan Africa, with with more than 4 million of inhabitants and a population growth rate of about 8 per cent per year. The city faces periodic water shortages, due to the lack of an adequate water supply network. These two factors have determined, in the last ten years, an increasing demand of groundwater exploitation, carried on by quite a number of private wells, which have been drilled to satisfy human demand. A steady-state three dimensional groundwater model has been set up by the MODFLOW code, and calibrated with the UCODE code for inverse modeling. The aim of the model was to carry out a characterization of groundwater flow system in the Dar es Salaam Coastal Plain. The inputs applied to the model included net recharge rate, calculated from time series of precipitation data (1961-2012), estimations of average groundwater extraction, and estimations of groundwater recharge, coming from zones, outside the area under study. Parametrization of the hydraulic conductivities was realized referring to the main geological features of the study area, based on available literature data and information. Boundary conditions were assigned based on hydrogeological boundaries. The conceptual model was defined in subsequent steps, which added some hydrogeological features and excluded other ones. Calibration was performed with UCODE 2014, using 76 measures of hydraulic head, taken in 2012 referred to the same season. Data were weighted on the basis of the expected errors. Sensitivity analysis of data was performed during calibration, and permitted to identify which parameters were possible to be estimated, and which data could support parameters estimation. Calibration was evaluated based on statistical index, maps of error distribution and test of independence of residuals. Further model

  19. The distribution and composition of REE-bearing minerals in placers of the Atlantic and Gulf coastal plains, USA

    USGS Publications Warehouse

    Bern, Carleton; Shah, Anjana K.; Benzel, William M.; Lowers, Heather

    2016-01-01

    Rare earth element (REE) resources are currently of great interest because of their importance as raw materials for high-technology manufacturing. The REE-phosphates monazite (light REE enriched) and xenotime (heavy REE enriched) resist weathering and can accumulate in placer deposits as part of the heavy mineral assemblage. The Atlantic and Gulf coastal plains of the southeastern United States are known to host heavy mineral deposits with economic concentrations of zircon, ilmenite and rutile. This study provides a perspective on the distribution and composition of REE phosphate minerals in the region. The elemental chemistry and mineralogy of sands and associated heavy-mineral assemblages from new and archived sediment samples across the coastal plains are examined, along with phase-specific compositions of monazite, xenotime and zircon. Both monazite and xenotime are present across the coastal plains. The phase-specific compositions allow monazite content to be estimated using La as a geochemical proxy. Similarly, both Y and Yb are geochemical proxies for xenotime, but their additional presence in zircon and monazite require a correction to prevent overestimation of xenotime content. Applying this correction, maps of monazite and xenotime content across the coastal plains were generated using sample coverage from the National Geochemical Database (NGS) and National Uranium Resource Evaluation (NURE). The NGS and NURE approach of sampling stream sediments in small watersheds links samples to nearby lithologies. The results show an approximately 40 km-wide band of primarily Cretaceous, marine sediments bordering the Piedmont province from North Carolina to Alabama in which monazite and xenotime content are relatively high (up to 4.4 wt. % in < 150 μm bulk sediment). Strong correlations between concentrations of the two phases were found, with estimated monazite:xenotime ratios ranging approximately 6:1 to 12:1 depending upon the dataset analyzed. From a resource

  20. Simulation of ground-water flow in the Coastal Plain aquifer system of North Carolina

    USGS Publications Warehouse

    Giese, G.I.; Eimers, J.L.; Coble, R.W.

    1997-01-01

    A three-dimensional finite-difference digital model was used to simulate ground-water flow in the 25,000-square-mile aquifer system of the North Carolina Coastal Plain. The model was developed from a hydrogeologic framework that is based on an alternating sequence of 10 aquifers and 9 confining units, which make up a seaward-thickening wedge of sediments that form the Coastal Plain aquifer system in the State of North Carolina. The model was calibrated by comparing observed and simulated water levels. The model calibration was achieved by adjusting model parameters, primarily leakance of confining units and transmissivity of aquifers, until differences between observed and simulated water levels were within acceptable limits, generally within 15 feet. The maximum transmissivity of an individual aquifer in the calibrated model is 200,000 feet squared per day in a part of the Castle Hayne aquifer, which consists predominantly of limestone. The maximum value for simulated vertical hydraulic conductivity in a confining unit was 2.5 feet per day, in a part of the confining unit overlying the upper Cape Fear aquifer. The minimum value was 4.1x10-6 feet per day, in part of the confining unit overlying the lower Cape Fear aquifer. Analysis indicated the model is highly sensitive to changes in transmissivity and leakance near pumping centers; away from pumping centers, the model is only slightly sensitive to changes in transmissivity but is moderately sensitive to changes in leakance. Recharge from precipitation to the surficial aquifer ranges from about 12 inches per year in areas having clay at the surface to about 20 inches per year in areas having sand at the surface. Most of this recharge moves laterally to streams, and only about 1 inch per year moves downward to the confined parts of the aquifer system. Under predevelopment conditions, the confined aquifers were generally recharged in updip interstream areas and discharged through streambeds and in downdip coastward

  1. Moisture and temperature controls on vertical and lateral soil greenhouse gas emissions in the Alaskan coastal temperate rainforest

    NASA Astrophysics Data System (ADS)

    D'Amore, D. V.; Herendeen, P. A.; Yardley, R. R.; Walter, M. T.

    2013-12-01

    The Perhumid Coastal Temperate Rainforest (PCTR) of Alaska and British Columbia is a coastal margin where intense transformations and rapid transfers between atmosphere, land, and ocean characterize the carbon cycle. The cool climate and high precipitation in the PCTR support uptake of atmospheric CO2 by forest and peatland ecosystems. The PCTR has some of the densest terrestrial carbon stocks in the world that is mobilized and re-distributed as dissolved and particulate carbon in streams, and gaseous efflux from both terrestrial and aquatic ecosystems. These stocks may be vulnerable to changes in soil moisture and temperature regimes that may have notable impacts to terrestrial and marine resources. In particular, methane and nitrous oxide have the potential to be produced in substantial amounts in these wet, organic rich soils and exported via vertical and lateral flux pathways. We have established an integrated catchment observatory to measure the vertical and lateral carbon export, including all greenhouse gases, from terrestrial to both atmospheric and aquatic systems. Initial estimates of net ecosystem production produced from a mass balance carbon flux model in these experimental watersheds ranged from 1.1 to 2.8 Mg C ha-1 y-1. The dissolved component of this flux budget ranged up to 30% of the total carbon export from the watersheds. Soil moisture and temperature fluctuations drive the variability in the overall flux, but the magnitude of lateral carbon delivery is dependent on moisture and temperature conditions within different landscape types, especially peatlands. These observations from the PCTR highlight the importance of lateral carbon fluxes in the total ecosystem carbon budget in this coastal margin system.

  2. Quaternary stratigraphy and sea-level history of the U.S. Middle Atlantic Coastal Plain

    NASA Astrophysics Data System (ADS)

    Toscano, Marguerite A.; York, Linda L.

    Middle-Atlantic, inner continental shelf stratigraphic studies document a regional, Late Pleistocene, fossiliferous mud deposit, from northern New Jersey to Cape Lookout, North Carolina. Seismic reconnaissance and detailed stratigraphic analyses reveal the nature of the mud, termed unit Q2, on the Maryland inner continental shelf. Extensive amino acid relative age determinations (from the single genus Mulinia), combined with additional amino acid analyses from onshore deposits having radiometric dates for calibration, indicate an age range for unit Q2 corresponding to Oxygen Isotope Stage 5. Ostracode assemblages delineate four distinct climatic episodes in unit Q2, enabling correlation of the zones in Q2 to the deep sea isotopic record of climatic fluctuations (substages) in Stage 5. Late Stage 5 is represented, on the Maryland shelf, by the 6 meter-thick mud of unit Q2, deposited in an open-shelf environment at slightly depressed sea levels relative to Substage 5e. Late Stage 5 sea levels (including sea-level minima) can be estimated for the mid-Atlantic Coastal Plain by direct measurement of the altitudes of ostracode zone boundaries offshore, and from peak transgressive facies in correlative deposits onshore. Late Stage 5 sea levels determined from the inner shelf and adjacent nearshore facies on the Atlantic coast comprise the most complete sea-level history for Stage 5 yet proposed. Some recent revisions of glacioeustatic sea-level models advocate slightly higher sea levels during late Stage 5 (Substage 5c in particular) than originally estimated from uplifting reef tracts, and support sea levels higher than estimates from deep-sea isotopic records. The sea-level record from the Maryland inner continental shelf confirms these recent estimates in an area of minimal tectonism, and adds sea-level minima estimates for Substages 5d and 5b. Offshore, a more complete record of Stage 5 is preserved than in onshore deposits, which are limited to peak transgressive

  3. High frequency water quality and flow observations of a hypereutrophic Coastal Plain millpond

    NASA Astrophysics Data System (ADS)

    Andres, S.; Ullman, W. J.; Voynova, Y. G.

    2014-12-01

    Eutrophication due to runoff of N and P occurs in many impoundments in agricultural areas around the world with deleterious impacts on fisheries, drinking water, and recreational resources. Coursey Pond, a hypereutrophic, shallow, Coastal Plain mill pond located on the Murderkill River in central Delaware has seasonal algal blooms between May and October. High frequency automated water quality, meteorlogical, and flow observations initiated in June 2014 as part of the NEWRNet project provide insights into the relationships between hydrologic events, changes in water quality, and primary productivity. During blooms the pond becomes stratified, allowing for dissolved oxygen (DO) levels at the surface to exceed 150% saturation, while DO within 2 m of the surface to falls below 50% saturation. During fair weather turbidity and dissolved organic carbon (DOC) also gradually rise. Turbidity, DOC, and DO quickly decrease in response to storms and increased flow, indicating that storms are important regulators of water column stratification. Decreases in primary productivity due to decreased sunlight, dilution by addition of rain and runoff, and mixing in response to storm winds and flows abruptly end blooms, although they often return within a few days of storm events. Analysis of hourly meterological data will help determine the importance of solar insolation, winds, and rainfall intensity to the timing, rate, and magnitude of these water quality changes. Groundwater is the primary source of water to the streams that feed the pond and delivers nitrogen as nitrate. Historical grab sample nitrate concentration data from summer months (<1 mg/L) in comparison to winter months (4-8 mg/L) indicate that primary productivity consumes nearly all available nitrate during algal blooms, and perhaps improving water quality in downstream areas. There is no clear relationship between storms, flow and nitrate in the short period of high frequency observations, when nitrate concentrations

  4. The origin of high sodium bicarbonate waters in the Atlantic and Gulf Coastal Plains

    USGS Publications Warehouse

    Foster, M.D.

    1950-01-01

    Some sodium bicarbonate waters at depth in the Atlantic and Gulf Coastal Plains have the same bicarbonate content as the shallower calcium bicarbonate waters in the same formation and appear to be the result of replacement of calcium by sodium through the action of base-exchange minerals. Others, however, contain several hundred parts per million more of bicarbonate than any of the calcium bicarbonate waters and much more bicarbonate than can be attributed to solution of calcium carbonate through the action of carbon dioxide derived from the air and soil. As the waters in the Potomac group (Cretaceous) are all low in sulphate and as the environmental conditions under which the sediments of the Potomac group were deposited do not indicate that large amounts of sulphate are available for solution, it does not seem probable that carbon dioxide generated by chemical or biochemical breakdown of sulphate is responsible for the high sodium bicarbonate waters in this area. Sulphate as a source of oxygen is not necessary for the generation of carbon dioxide by carbonaceous material. Oxygen is an important constituent of carbonaceous material and carbon dioxide is a characteristic decomposition product of such material-as, for example, peat and lignite. Experimental work showed that distilled water, calcium bicarbonate water, and sodium bicarbonate water, after contact with lignite, calcium carbonate, and permutite (a base-exchange material), had all increased greatly in sodium bicarbonate content and had become similar in chemical character and in mineral content to high sodium bicarbonate waters found in the Coastal Plain. The tests indicated that carbonaceous material can act as a source of carbon dioxide, which, when dissolved in water, enables it to take into solution more calcium carbonate. If base-exchange materials are also present to replace calcium with sodium, a still greater amount of bicarbonate can be held in solution. The presence of carbonaceous material

  5. Simulation of ground-water flow in the coastal plain aquifer system of North Carolina

    USGS Publications Warehouse

    Giese, G.L.; Eimers, J.L.; Coble, R.W.

    1991-01-01

    A 3-D finite difference digital model was used to simulate groundwater flow in the 25,000 sq mi aquifer system of the North Carolina Coastal Plain. The model was developed from a geohydrologic framework that is based on an alternating sequence of 10 aquifers and 9 confining units, which comprise a seaward-thickening wedge of sediments that form the Coastal Plain aquifer system in North Carolina. The model was calibrated by comparing observed and simulated water levels. The maximum transmissivity of an individual aquifer in the calibrated model is 200,000 sq ft/d in a part of the Castle Hayne aquifer, which is composed predominately of limestone. The maximum simulated vertical hydraulic conductivity in a confining unit was 2.5 ft/d in a part of the confining unit overlying the upper Cape Fear aquifer. Analysis indicated the model is highly sensitive to changes in transmissivity and leakage near pumping centers; away from pumping centers, the model is only slightly sensitive to changes in transmissivity but is moderately sensitive to changes in leakance. Recharge from precipitation to the surficial aquifer ranges from about 12 in/yr in areas having clay at the surface, to about 20 in/yr in areas having sand at the surface. Most of this recharge moves laterally to streams, with only about 1 in/yr moving down to the confined parts of the aquifer system. Groundwater level declines, which are the result of water taken from storage, are extensive in some area and minimal in others. Water level declines exceeding 100 ft have occurred in the Beaufort County area because of withdrawals for a mining operation and water supplies for a chemical plant. Head declines have been less than 10 ft in the shallow surficial and Yorktown aquifers and in the updip parts of the major confined aquifers distant from areas of major withdrawals. A water-budget analysis using the model simulations indicates that much of the water removed from the groundwater system by pumping ultimately is made

  6. Modern Environmental Changes on Amapa Coastal Plain under Amazon River Influence

    NASA Astrophysics Data System (ADS)

    Santos, V. F.; Figueiredo, A. G.; Silveira, O. M.; Polidori, L.

    2007-05-01

    The Amazonian coastal environment is very dynamic compared to other coasts. It is situated at the edge of the Earth's largest forest, and is segmented by fluvial systems, with the biggest being the Amazon River. The rivers are particularly influenced by the Intertropical Convergence Zone (ITCZ), which controls the water and particle discharge, and the flooding regime. Moderate and strong El Nino conditions correlate with low-precipitation periods, and La Nina events cause precipitation to increase. These variables and others related to the Amazon dispersal system create an interesting area for the study of global and regional environmental changes. The Araguari River floodplain on the Amapa coast is influenced by natural processes of global scale such as ENSO events and ITCZ, and by local processes such as Amazon River discharge, tides and tidal bore (pororoca). Anthropogenic processes such as extensive water-buffalo farming also promote environmental changes. Time- series analyses of remote sensing images and suspended sediment have shown that the maximum turbidity zone inside Araguari River is related to the pororoca phenomenon. The pororoca remobilizes sediment from the river bottom and margins, developing sediment suspension >15 g/l as it passes - creating fluid muds. The pororoca also introduces Amazon- and shelf-derived sediment into the Araguari estuary. Measurements during eight spring-tide cycles indicate erosion of 3 cm of consolidated mud and deposition of 1 cm. The pororoca also influences the remobilization and cycling of nutrients and consequently affects the distribution of benthic organisms, including benthonic foraminifera and thecamoebians. For more than a century, the coastal plain has had water-buffalo farming (>42,000 animals today), which modifies the drainage system and affects sedimentary processes. Areas with more buffalo trails have higher suspended-sediment concentration (SSC) during the dry season and lower SSC during the rainy season

  7. Summer Roost Tree Selection by Eastern Red, Seminole, and Evening Bats in the Upper Coastal Plain of South Carolina

    SciTech Connect

    Menzel, M.A.; Carter, T.C.; Ford, W.M.; Chapman, B.R.; Ozier, J.

    2000-01-01

    Radiotraction of six eastern red bats, six seminole bats and twenty-four evening bats to 55, 61, and 65 day roosts during 1996 to 1997 in the Upper Coastal Plain of South Carolina. For each species, testing was done for differences between used roost trees and randomly located trees. Also tested for differences between habitat characteristics surrounding roost trees and randomly located trees. Eastern Red and Seminole bats generally roosted in canopies of hardwood and pine while clinging to foilage and small branches. Evening bats roosted in cavities or under exfoliating bark in pines and dead snags. Forest management strategies named within the study should be beneficial for providing roosts in the Upper Coastal Plain of South Carolina.

  8. Ecosystem carbon balance and vulnerability of soil carbon in a drained lower coastal plain loblolly pine plantation

    NASA Astrophysics Data System (ADS)

    Noormets, A.; McNulty, S. G.; Gavazzi, M.; Domec, J.; Sun, G.; King, J. S.; Chen, J.

    2008-12-01

    Coastal plain ecosystems comprise only about 5% of total U.S. land area, but the soil carbon density in these ecosystems is about 10-fold higher than in upland ecosystems and they may therefore play a disproportionately large role in ecosystem-climate feedbacks. The role of these ecosystems in continental carbon exchange is largely unclear because they have been underrepresented in flux monitoring networks. We monitored ecosystem carbon fluxes and pools for three years in two lower coastal plain loblolly pine plantations (3 and 17 years of age). The contribution of soil to ecosystem respiration decreased from over 90% immediately following a harvest to about 50% by age 17. The replenishment of soil C through litterfall exceeded heterotrophic respiration (Rh) by 2-9% in two years, but was 30% lower than Rh in the third year, highlighting the vulnerability of soil carbon stocks to interannual climate variability.

  9. Effect of coarse woody debris manipulation on soricid and herpetofaunal communities in upland pine stands of the southeastern coastal plain.

    SciTech Connect

    Davis, Justin, Charles

    2009-04-01

    Abstract -The majority of studies investigating the importance of coarse woody debris (CWD) to forest- floor vertebrates have taken place in the Pacific Northwest and southern Appalachian Mountains, while comparative studies in the southeastern Coastal Plain are lacking. My study was a continuation of a long-term project investigating the importance of CWD as a habitat component for shrew and herpetofaunal communities within managed pine stands in the southeastern Coastal Plain. Results suggest that addition of CWD can increase abundance of southeastern and southern short-tailed shrews. However, downed wood does not appear to be a critical habitat component for amphibians and reptiles. Rising petroleum costs and advances in wood utilization technology have resulted in an emerging biofuels market with potential to decrease CWD volumes left in forests following timber harvests. Therefore, forest managers must understand the value of CWD as an ecosystem component to maintain economically productive forests while conserving biological diversity.

  10. Jurassic petroleum trends in eastern Gulf Coastal Plain and central and eastern Gulf of Mexico

    SciTech Connect

    Mancini, E.A.; Mink, R.M.; Bearden, B.L.

    1986-05-01

    Three Jurassic petroleum trends can be delineated in Mississippi, Alabama, and Florida, and in the central and eastern Gulf of Mexico. These trends are recognized by characteristic petroleum traps, reservoirs, and hydrocarbon types. The source for the Jurassic hydrocarbons is Smackover algal mudstones. The Jurassic oil trend includes the area north of the regional peripheral fault systems in the tri-state area, and extends into the area north of the Destin anticline. Traps are basement highs and salt anticlines, with Smackover grainstones and dolostones and Norphlet marine, eolian, and wadi sandstones as reservoirs. This trend has potential for Jurassic oil accumulations in the eastern Gulf of Mexico. The Jurassic oil and gas-condensate trend includes the onshore area between the regional peripheral fault systems and Wiggins arch and extends into the area of the Destin anticline. Traps are basement highs, salt related anticlines, and extensional faults. Cotton Valley fluvial-deltaic sandstones, Haynesville carbonates and fluvial-deltaic sandstones, Smackover grainstones, packstones, dolostones, and marine sandstones, and Norphlet marine, eolian, and wadi sandstones serve as reservoirs. This trend contains most of the Jurassic fields in the eastern Gulf coastal plain. The trend has high potential for significant petroleum accumulations in the eastern Gulf of Mexico. The Jurassic deep natural gas trend includes the onshore area south of the Wiggins arch and extends into the Mississippi-Alabama shelf. Traps are faulted salt anticlines with basement highs as potential traps. Cotton Valley deltaic-strandplain sandstones and Norphlet eolian sandstones are the reservoirs. Several gas discoveries below 20,000 ft have been made in this trend in Mississippi and offshore Alabama. The trend has excellent potential for major gas accumulations in coastal Alabama and central Gulf of Mexico.

  11. Predicting breeding shorebird distributions on the Arctic Coastal Plain of Alaska

    USGS Publications Warehouse

    Saalfeld, Sarah T.; Lanctot, Richard B.; Brown, Stephen C.; Saalfeld, David T.; Johnson, James A.; Andres, Brad A.; Bart, Jonathan R.

    2013-01-01

    The Arctic Coastal Plain (ACP) of Alaska is an important region for millions of migrating and nesting shorebirds. However, this region is threatened by climate change and increased human development (e.g., oil and gas production) that have the potential to greatly impact shorebird populations and breeding habitat in the near future. Because historic data on shorebird distributions in the ACP are very coarse and incomplete, we sought to develop detailed, contemporary distribution maps so that the potential impacts of climate-mediated changes and development could be ascertained. To do this, we developed and mapped habitat suitability indices for eight species of shorebirds (Black-bellied Plover [Pluvialis squatarola], American Golden-Plover [Pluvialis dominica], Semipalmated Sandpiper [Calidris pusilla], Pectoral Sandpiper [Calidris melanotos], Dunlin [Calidris alpina], Long-billed Dowitcher [Limnodromus scolopaceus], Red-necked Phalarope [Phalaropus lobatus], and Red Phalarope [Phalaropus fulicarius]) that commonly breed within the ACP of Alaska. These habitat suitability models were based on 767 plots surveyed during nine years between 1998 and 2008 (surveys were not conducted in 2003 and 2005), using single-visit rapid area searches during territory establishment and incubation (8 June, 1 July). Species specific habitat suitability indices were developed and mapped using presence-only modeling techniques (partitioned Mahalanobis distance) and landscape environmental variables. For most species, habitat suitability was greater at lower elevations (i.e., near the coast and river deltas) and lower within upland habitats. Accuracy of models was high for all species, ranging from 65 -98%. Our models predicted that the largest fraction of suitable habitat for the majority of species occurred within the National Petroleum Reserve-Alaska, with highly suitable habitat also occurring within coastal areas of the Arctic National Wildlife Refuge west to Prudhoe Bay.

  12. Mesozoic (Upper Jurassic-Lower Cretaceous) deep gas reservoir play, central and eastern Gulf coastal plain

    USGS Publications Warehouse

    Mancini, E.A.; Li, P.; Goddard, D.A.; Ramirez, V.O.; Talukdar, S.C.

    2008-01-01

    The Mesozoic (Upper Jurassic-Lower Cretaceous) deeply buried gas reservoir play in the central and eastern Gulf coastal plain of the United States has high potential for significant gas resources. Sequence-stratigraphic study, petroleum system analysis, and resource assessment were used to characterize this developing play and to identify areas in the North Louisiana and Mississippi Interior salt basins with potential for deeply buried gas reservoirs. These reservoir facies accumulated in Upper Jurassic to Lower Cretaceous Norphlet, Haynesville, Cotton Valley, and Hosston continental, coastal, and marine siliciclastic environments and Smackover and Sligo nearshore marine shelf, ramp, and reef carbonate environments. These Mesozoic strata are associated with transgressive and regressive systems tracts. In the North Louisiana salt basin, the estimate of secondary, nonassociated thermogenic gas generated from thermal cracking of oil to gas in the Upper Jurassic Smackover source rocks from depths below 3658 m (12,000 ft) is 4800 tcf of gas as determined using software applications. Assuming a gas expulsion, migration, and trapping efficiency of 2-3%, 96-144 tcf of gas is potentially available in this basin. With some 29 tcf of gas being produced from the North Louisiana salt basin, 67-115 tcf of in-place gas remains. Assuming a gas recovery factor of 65%, 44-75 tcf of gas is potentially recoverable. The expelled thermogenic gas migrated laterally and vertically from the southern part of this basin to the updip northern part into shallower reservoirs to depths of up to 610 m (2000 ft). Copyright ?? 2008. The American Association of Petroleum Geologists. All rights reserved.

  13. Spatial and Temporal Variation in Primary Productivity (NDVI) of Coastal Alaskan Tundra: Decreased Vegetation Growth Following Earlier Snowmelt

    NASA Technical Reports Server (NTRS)

    Gamon, John A.; Huemmrich, K. Fred; Stone, Robert S.; Tweedie, Craig E.

    2015-01-01

    In the Arctic, earlier snowmelt and longer growing seasons due to warming have been hypothesized to increase vegetation productivity. Using the Normalized Difference Vegetation Index (NDVI) from both field and satellite measurements as an indicator of vegetation phenology and productivity, we monitored spatial and temporal patterns of vegetation growth for a coastal wet sedge tundra site near Barrow, Alaska over three growing seasons (2000-2002). Contrary to expectation, earlier snowmelt did not lead to increased productivity. Instead, productivity was associated primarily with precipitation and soil moisture, and secondarily with growing degree days, which, during this period, led to reduced growth in years with earlier snowmelt. Additional moisture effects on productivity and species distribution, operating over a longer time scale, were evident in spatial NDVI patterns associated with microtopography. Lower, wetter regions dominated by graminoids were more productive than higher, drier locations having a higher percentage of lichens and mosses, despite the earlier snowmelt at the more elevated sites. These results call into question the oft-stated hypothesis that earlier arctic growing seasons will lead to greater vegetation productivity. Rather, they agree with an emerging body of evidence from recent field studies indicating that early-season, local environmental conditions, notably moisture and temperature, are primary factors determining arctic vegetation productivity. For this coastal arctic site, early growing season conditions are strongly influenced by microtopography, hydrology, and regional sea ice dynamics, and may not be easily predicted from snowmelt date or seasonal average air temperatures alone. Our comparison of field to satellite NDVI also highlights the value of in-situ monitoring of actual vegetation responses using field optical sampling to obtain detailed information on surface conditions not possible from satellite observations alone.

  14. Hydrogeochemical considerations about the origin of groundwater salinization in some coastal plains of Elba Island (Tuscany, Italy).

    PubMed

    Giménez-Forcada, Elena; Bencini, Alberto; Pranzini, Giovanni

    2010-06-01

    Several coastal plains of the Elba Island (Marina di Campo, Portoferraio, Schiopparello, Mola, Porto Azzurro and Barbarossa plains) in Tuscany (Italy) were studied to determine the causes of decline in groundwater quality, using major ion chemistry to establish the causes of groundwater salinization. The study demonstrates that salinization of coastal plain alluvial aquifers is not simply linked to seawater intrusion but is also intimately related to inflows from adjacent aquifers. Ionic ratios, correlation graphs and distribution value maps were employed as the means to understand the hydrochemistry of the study areas. The Mg/Cl ratio in particular can be considered a good tracer to distinguish the main salinization processes that control groundwater chemistry. Seawater intrusion only partly determines the chemistry of some groundwaters, which generally belong to a chloride facies where the salinity is derived principally from freshwater-seawater mixing and the participation of cation exchange. Proceeding inland groundwater quality seems to be principally determined by the inflow of Mg, Ca-HCO(3) or Ca, Na-HCO(3) waters formed from the weathering of silicate minerals in adjoining aquifers. Hydrolysis of these minerals is of prime importance in controlling groundwater chemistry in adjacent alluvial plains. The lateral recharge flows introduce water with a different chemical composition and this variable of freshwater recharge changes the hydrochemistry as a result of mixing between two or more waters types. This situation is further complicated when seawater and base exchange reactions participate, due to seawater intrusion.

  15. Shifting balance of thermokarst lake ice regimes across the Arctic Coastal Plain of northern Alaska

    USGS Publications Warehouse

    Arp, Christopher D.; Jones, Benjamin M.; Lu, Zong; Whitman, Matthew S.

    2012-01-01

    The balance of thermokarst lakes with bedfast- and floating-ice regimes across Arctic lowlands regulates heat storage, permafrost thaw, winter-water supply, and over-wintering aquatic habitat. Using a time-series of late-winter synthetic aperture radar (SAR) imagery to distinguish lake ice regimes in two regions of the Arctic Coastal Plain of northern Alaska from 2003–2011, we found that 18% of the lakes had intermittent ice regimes, varying between bedfast-ice and floating-ice conditions. Comparing this dataset with a radar-based lake classification from 1980 showed that 16% of the bedfast-ice lakes had shifted to floating-ice regimes. A simulated lake ice thinning trend of 1.5 cm/yr since 1978 is believed to be the primary factor driving this form of lake change. The most profound impacts of this regime shift in Arctic lakes may be an increase in the landscape-scale thermal offset created by additional lake heat storage and its role in talik development in otherwise continuous permafrost as well as increases in over-winter aquatic habitat and winter-water supply.

  16. Susceptibility of coastal plain aquifers to contamination, Fairfax County, Virginia; a computer composite map

    USGS Publications Warehouse

    Johnston, Richard H.; Van Driel, J. Nicholas

    1978-01-01

    A map is presented that classifies the Coastal Plain of Fairfax County, Virginia according to the susceptibility of the principal sand aquifers to contamination from surface sources. The following classification is used: (1) areas where leachate can readily enter the principal sand aquifers, (2) areas offering great natural protection against migration of leachate into the aquifers, and, (3) areas where the contamination risk is uncertain and onsite investigations are needed. Approximately 20 percent of the area is in the high-risk category. The map is computer generated and was made by combining four source maps depicting those hydrogeologic factors related to movement of contaminants into the aquifers. These factors are (1) lithologic character of the upper 25 feet of sediments, (2) clay thickness above uppermost sand aquifer, (3) hydraulic gradient direction and head difference between water table and artesian head in principal aquifer, and (4) areal occurrence of moderate to high transmissiviry aquifers. The map is designed to be used by planners with little or no earth-science background, however, a technical discussion for hydrologists and geologists is also provided. (Woodard-USGS)

  17. Forest statistics for the northern coastal plain of South Carolina, 1992. Forest Service resource bulletin

    SciTech Connect

    Thompson, M.T.; Sheffield, R.M.

    1993-05-01

    Since 1986, the area of timberland in the Northern Coastal Plain of South Carolina increased by 3 percent to 4.7 million acres. Nonindustrial private forest landowners control 67 percent of the region's timberland. Area classified as a pine type remained stable at 1.9 million acres. More than 116,000 acres were harvested annually, while 177,000 acres were regenerated by artificial and natural means. The volume of softwood growing stock decreased 26 percent to 2.5 billion cubic feet. The volume of hardwood growing stock declined 13 percent to 3.1 billion cubic feet. Extremely high mortality drove net growth downward. Net annual growth of softwoods declined 84 percent to 28 million cubic feet. Hardwood growth dropped 77 percent to 23 million cubic feet. Annual removals of softwood growing stock increased 9 percent to 175 million cubic feet; hardwood removals jumped 18 percent to 87 million cubic feet. Annual mortality of softwood growing stock was up eight times the level recorded in 1986, whereas hardwood mortality was up four times the previous level.

  18. The Sunny Point Formation: a new Upper Cretaceous subsurface unit in the Carolina Coastal Plain

    USGS Publications Warehouse

    Balson, Audra E.; Self-Trail, Jean; Terry, Dennis O.

    2013-01-01

    This paper formally defines the Sunny Point Formation, a new Upper Cretaceous subsurface unit confined to the outer Atlantic Coastal Plain of North and South Carolina. Its type section is established in corehole NH-C-1-2001 (Kure Beach) from New Hanover County, North Carolina. The Sunny Point Formation consists of light-olive-gray to greenish-gray, fine to coarse micaceous sands and light-olive-brown and grayish-red silty, sandy clays. The clay-rich sections typically include ironstone, lignitized wood, root traces, hematite concretions, goethite, limonite, and sphaerosiderites. The Sunny Point Formation is also documented in cores from Bladen County, North Carolina, and from Dorchester and Horry Counties, South Carolina. Previously, strata of the Sunny Point Formation had been incorrectly assigned to the Cape Fear and Middendorf Formations. The Sunny Point occupies a stratigraphic position above the Cenomanian marine Clubhouse Formation and below an upper Turonian unnamed marine unit. Contacts between these units are sharp and unconformable. Calcareous nannofossil and palynomorph analyses indicate that the Sunny Point Formation is Turonian.

  19. Forest response and recovery following disturbance in upland forests of the Atlantic Coastal Plain

    PubMed Central

    Schäfer, Karina V. R.; Renninger, Heidi J.; Carlo, Nicholas J.; Vanderklein, Dirk W.

    2014-01-01

    Carbon and water cycling of forests contribute significantly to the Earth's overall biogeochemical cycling and may be affected by disturbance and climate change. As a larger body of research becomes available about leaf-level, ecosystem and regional scale effects of disturbances on forest ecosystems, a more mechanistic understanding is developing which can improve modeling efforts. Here, we summarize some of the major effects of physical and biogenic disturbances, such as drought, prescribed fire, and insect defoliation, on leaf and ecosystem-scale physiological responses as well as impacts on carbon and water cycling in an Atlantic Coastal Plain upland oak/pine and upland pine forest. During drought, stomatal conductance and canopy stomatal conductance were reduced, however, defoliation increased conductance on both leaf-level and canopy scale. Furthermore, after prescribed fire, leaf-level stomatal conductance was unchanged for pines but decreased for oaks, while canopy stomatal conductance decreased temporarily, but then rebounded the following growing season, thus exhibiting transient responses. This study suggests that forest response to disturbance varies from the leaf to ecosystem level as well as species level and thus, these differential responses interplay to determine the fate of forest structure and functioning post disturbance. PMID:25018759

  20. Bacteria in deep coastal plain sediments of Maryland: A possible source of CO2 to groundwater

    NASA Astrophysics Data System (ADS)

    Chapelle, Francis H.; Zelibor, Joseph L., Jr.; Grimes, D. Jay; Knobel, Leroy L.

    1987-08-01

    Nineteen cores of unconsolidated Coastal Plain sediments obtained from depths of 14 to 182 m below land surface near Waldorf, Maryland, were collected and examined for metabolically active bacteria. The age of the sediments cored range from Miocene to Early Cretaceous. Acridine orange direct counts of total (viable and nonviable) bacteria in core subsamples ranged from 108 to 104 bacteria/g of dry sediment. Direct counts of viable bacteria ranged from 106 to 103 bacteria/g of dry sediment. Three cores contained viable methanogenic bacteria, and seven cores contained viable sulfate-reducing bacteria. The observed presence of bacteria in these sediments suggest that heterotrophic bacterial metabolism, with lignitic organic material as the primary substrate, is a plausible source of CO2 to groundwater. However, the possibility that abiotic processes also produce CO2 cannot be ruled out. Estimated rates of CO2 production in the noncalcareous Magothy/Upper Patapsco and Lower Patapsco aquifers based on mass balance of dissolved inorganic carbon, groundwater flow rates, and flow path segment lengths are in the range 10-3 to 10-5 mmol L-1 yr-1. Isotope balance calculations suggest that aquifer-generated CO2 is much heavier isotopically (˜—10 to + 5 per mil) than lignite (˜-24 per mil) present in these sediments. This may reflect isotopic fractionation during methanogenesis and possibly other bacterially mediated processes.

  1. Distribution of total and fecal coliform organisms from septic effluent in selected coastal plain soils.

    PubMed Central

    Reneau, R B; Pettry, D E; Shanholtz, M I; Graham, S A; Weston, C W

    1977-01-01

    Distribution of total and fecal coliform bacteria in three Atlantic coastal plain soils in Virginia were monitored in situ over a 3-year period. The soils studied were Varina, Goldsboro, and Beltsville sandy loams. These and similar soils are found extensively along the populous Atlantic seaboard of the United States. They are considered only marginally suitable for septic tank installation because the restricting soil layers result in the subsequent development of seasonal perched water tables. To determine both horizontal and vertical movement of indicator organisms, samples were collected from piezometers placed at selected distances and depths from the drainfields in the direction of the ground water flow. Large reductions in total and fecal coliform bacteria were noted in the perched ground waters above the restricting layers as distance from the drainfield increased. These restricting soil layers appear to be effective barriers to the vertical movement of indicator organisms. The reduction in the density of the coliform bacteria above the restricting soil layers can probably be attributed to dilution, filtration, and dieoff as the bacteria move through the natural soil systems. PMID:325589

  2. Selective extinction and survival across the Cretaceous/Tertiary boundary in the northern Atlantic Coastal Plain

    SciTech Connect

    Gallagher, W.B. )

    1991-10-01

    The inner Atlantic Coastal Plain in New Jersey and the Delmarva Peninsula is underlain by an Upper Cretaceous-lower Tertiary sequence of marine and paralic sand, clay, and glauconitic beds. Campanian, Maastrichtian, Danian, and Thanetian deposits are especially fossiliferous and yield a succession of marine faunas that reveal a pattern of selective extinction and survival across the Cretaceous/Tertiary (K/T) boundary in this area. Cretaceous benthic invertebrate communities are dominated by oysters and other semi-infaunal and infaunal molluscs with planktotrophic larval stages. These are replaced in the Danian by brachiopod-dominated communities that are composed of epifaunal benthos with a variety of nonplanktotrophic reproductive strategies. A similar pattern is observable in the nektonic cephalopod populations in this sequence; the typical ammonites of the Cretaceous became extinct at the K/T boundary, whereas the nautilids survived. Ammonites are thought to have had a planktotrophic larval stage, whereas nautilids are known to lay large lecithotrophic eggs. This pattern of differential survival is attributed to the planktonic population crash at the K/T boundary which placed planktotrophically reproducing species at a disadvantage while favoring the varied groups that practiced alternative reproductive strategies.

  3. Quality of groundwater in the Coastal Plain Sands aquifer of the Akwa Ibom State, Nigeria

    NASA Astrophysics Data System (ADS)

    Ajayi, Owolabi; Umoh, Obot A.

    1998-08-01

    The Coastal Plain Sands Formation is exploited by most of the population of the Akwa Ibom State in southeastern Nigeria. The aquifer is mostly coarse-grained, pebbly and poorly sorted sands with minor clay intercalations. It is up to 1500 m thick near the coast, but only a few metres thick along the northeastern boundary. Groundwater occurs principally under unconfined conditions. Boreholes penetrating less than 130 m yield over 300 m 3 hr -1. The main groundwater flow direction is seaward from north to south. The probable location of the fresh water-sea water interface is seaward. Forty-two groundwater and two surface water samples were analysed. Groundwater quality meets the WHO standards for potability and is dominated by bicarbonates of Na, Ca and Mg. The Sodium Adsorption Ratio lies between 0.2 and 2.0, indicating that the water is suitable for irrigation. The area has very high annual rainfall exceeding 2000 mm annually. Groundwater recharge should be high, although it is recommended that groundwater levels and quality near the coast be monitored regularly, especially in urban areas with high groundwater abstraction, to detect the onset of sea water intrusion which remains a potential hazard in this area.

  4. Warming-Induced Shrub Expansion and Lichen Decline Across the Tuktoyaktuk Coastal Plain

    NASA Astrophysics Data System (ADS)

    Fraser, R.; Lantz, T. C.; Olthof, I.; Kokelj, S. V.; Sims, R. A.

    2014-12-01

    Recent field and remote sensing studies show that shrub expansion has been widespread in low-Arctic ecosystems. However, there are still uncertainties regarding the extent of these changes, the plant functional groups involved, and the relative importance of climate and disturbance as causes of observed changes. Some authors have suggested that shrub expansion may have caused declines in lichens important for caribou forage, but these changes have not been examined at regional scales. Our research on the Tuktoyaktuk Coastal Plain using 30m resolution Landsat satellite imagery from 1985-2011 and high resolution (1:2000) vertical aerial photographs from 1980 and 2013 shows that shrub expansion has been associated with widespread lichen decline . Our analysis shows that the most likely driver of shrub expansion is a 4°C winter temperature increase over the past 30 years, leading to warmer soils and enhanced supply of growth-limiting nutrients. Natural and human-caused disturbances also stimulated increases in shrub cover, but these effects were limited spatially. Our observations are consistent with plot-scale warming experiments showing reductions in lichen cover from shrub growth, and modeling studies predicting large-scale vegetation shifts in the low-Arctic from climate change. These vegetation changes have implications for caribou forage, wildfire regimes, and permafrost conditions.

  5. Groundwater-derived contaminant fluxes along a channelized Coastal Plain stream

    SciTech Connect

    LaSage, Danita m; Fryar, Alan E; Mukherjee, Abhijit; Sturchio, Neil C; Heraty, Linnea J

    2008-10-01

    Recent studies in various settings across eastern North America have examined the movement of volatile organic compound (VOC) plumes from groundwater to streams, but few studies have addressed focused discharge of such plumes in unlithified sediments. From 1999 through 2002, we monitored concentrations of trichloroethene (TCE) and the non-volatile co-contaminant technetium-99 along Little Bayou Creek, a first -order perennial stream in the Coastal Plain of western Kentucky. Spring flow contributed TCE and technetium-99 to the creek, and TCE concentrations tended to vary with technetium-99 in springs. Contaminant concentrations in stream water fluctuated seasonally, but not always synchronously with stream flow. However, contaminant influxes varied seasonally with stream flow and were dominated by a few springs. Concentrations of O2, NO3⁻, and SO2-4, values of δ37CL in groundwater, and the lack of less-chlorinated ethenes in groundwater and stream water indicated that aerobic biodegradation of TCE was unlikely. Losses of TCE along Little Bayou Creek resulted mainly from volatilization, in contrast to streams receiving diffuse contaminated discharge, where intrinsic bioremediation of VOCs appears to be prevalent.

  6. Presence and absence of bats across habitat scales in the Upper Coastal Plain of South Carolina.

    SciTech Connect

    Ford, W.Mark; Menzel, Jennifer M.; Menzel, Michael A.: Edwards, John W.; Kilgo, John C.

    2006-10-01

    Abstract During 2001, we used active acoustical sampling (Anabat II) to survey foraging habitat relationships of bats on the Savannah River Site (SRS) in the upper Coastal Plain of South Carolina. Using an a priori information-theoretic approach, we conducted logistic regression analysis to examine presence of individual bat species relative to a suite of microhabitat, stand, and landscape-level features such as forest structural metrics, forest type, proximity to riparian zones and Carolina bay wetlands, insect abundance, and weather. There was considerable empirical support to suggest that the majority of the activity of bats across most of the 6 species occurred at smaller, stand-level habitat scales that combine measures of habitat clutter (e.g., declining forest canopy cover and basal area), proximity to riparian zones, and insect abundance. Accordingly, we hypothesized that most foraging habitat relationships were more local than landscape across this relatively large area for generalist species of bats. The southeastern myotis (Myotis austroriparius) was the partial exception, as its presence was linked to proximity of Carolina bays (best approximating model) and bottomland hardwood communities (other models with empirical support). Efforts at SRS to promote open longleaf pine (Pinus palustris) and loblolly pine (P. taeda) savanna conditions and to actively restore degraded Carolina bay wetlands will be beneficial to bats. Accordingly, our results should provide managers better insight for crafting guidelines for bat habitat conservation that could be linked to widely accepted land management and environmental restoration practices for the region.

  7. Application of a multipurpose unequal probability stream survey in the Mid-Atlantic Coastal Plain

    USGS Publications Warehouse

    Ator, S.W.; Olsen, A.R.; Pitchford, A.M.; Denver, J.M.

    2003-01-01

    A stratified, spatially balanced sample with unequal probability selection was used to design a multipurpose survey of headwater streams in the Mid-Atlantic Coastal Plain. Objectives for the survey include unbiased estimates of regional stream conditions, and adequate coverage of unusual but significant environmental settings to support empirical modeling of the factors affecting those conditions. The design and field application of the survey are discussed in light of these multiple objectives. A probability (random) sample of 175 first-order nontidal streams was selected for synoptic sampling of water chemistry and benthic and riparian ecology during late winter and spring 2000. Twenty-five streams were selected within each of seven hydrogeologic subregions (strata) that were delineated on the basis of physiography and surficial geology. In each subregion, unequal inclusion probabilities were used to provide an approximately even distribution of streams along a gradient of forested to developed (agricultural or urban) land in the contributing watershed. Alternate streams were also selected. Alternates were included in groups of five in each subregion when field reconnaissance demonstrated that primary streams were inaccessible or otherwise unusable. Despite the rejection and replacement of a considerable number of primary streams during reconnaissance (up to 40 percent in one subregion), the desired land use distribution was maintained within each hydrogeologic subregion without sacrificing the probabilistic design.

  8. Assessing groundwater availability in the Northern Atlantic Coastal Plain aquifer system

    USGS Publications Warehouse

    Masterson, John P.; Pope, Jason P.; Monti, Jack; Nardi, Mark R.

    2011-01-01

    The U.S. Geological Survey's Groundwater Resources Program is conducting an assessment of groundwater availability throughout the United States to gain a better understanding of the status of the Nation's groundwater resources and how changes in land use, water use, and climate may affect those resources. The goal of this National assessment is to improve our ability to forecast water availability for future economic and environmental uses. Assessments will be completed for the Nation's principal aquifer systems to help characterize how much water is currently available, how water availability is changing, and how much water we can expect to have in the future (Reilly and others, 2008). The concept of groundwater availability is more than just how much water can be pumped from any given aquifer. Groundwater availability is a function of many factors, including the quantity and quality of water and the laws, regulations, economics, and environmental factors that control its use. The primary objective of the North Atlantic Coastal Plain groundwater-availability study is to identify spatial and temporal changes in the overall water budget by more fully determining the natural and human processes that control how water enters, moves through, and leaves the groundwater system. Development of tools such as numerical models can help hydrologists gain an understanding of this groundwater system, allowing forecasts to be made about the response of this system to natural and human stresses, and water quality and ecosystem health to be analyzed, throughout the region.

  9. Floodplain geomorphic processes and environmental impacts of human alteration along coastal plain rivers, USA

    USGS Publications Warehouse

    Hupp, C.R.; Pierce, A.R.; Noe, G.B.

    2009-01-01

    Human alterations along stream channels and within catchments have affected fluvial geomorphic processes worldwide. Typically these alterations reduce the ecosystem services that functioning floodplains provide; in this paper we are concerned with the sediment and associated material trapping service. Similarly, these alterations may negatively impact the natural ecology of floodplains through reductions in suitable habitats, biodiversity, and nutrient cycling. Dams, stream channelization, and levee/canal construction are common human alterations along Coastal Plain fluvial systems. We use three case studies to illustrate these alterations and their impacts on floodplain geomorphic and ecological processes. They include: 1) dams along the lower Roanoke River, North Carolina, 2) stream channelization in west Tennessee, and 3) multiple impacts including canal and artificial levee construction in the central Atchafalaya Basin, Louisiana. Human alterations typically shift affected streams away from natural dynamic equilibrium where net sediment deposition is, approximately, in balance with net erosion. Identification and understanding of critical fluvial parameters (e.g., stream gradient, grain-size, and hydrography) and spatial and temporal sediment deposition/erosion process trajectories should facilitate management efforts to retain and/or regain important ecosystem services. ?? 2009, The Society of Wetland Scientists.

  10. Hydrochemical processes regulating groundwater quality in the coastal plain of Al Musanaah, Sultanate of Oman

    NASA Astrophysics Data System (ADS)

    Askri, Brahim

    2015-06-01

    The Al Batinah coastal aquifer is the principal source of water in northwestern Oman. The rainfall in the Jabal Al Akhdar mountain region recharges the plain with freshwater that allowed agricultural and industrial activities to develop. The over-exploitation of this aquifer since the 1970s for municipal, agricultural and industrial purposes, excessive use of fertilizers in agriculture and leakage from septic tanks led to the deterioration of groundwater quality. The objective of this study was to investigate the hydrochemical processes regulating the groundwater quality in the southwestern section of Al Batinah. From available data collected during the spring of 2010 from 58 wells located in Al Musanaah wilayat, it was determined that the groundwater salinity increased in the direction from the south to the north following the regional flow direction. In addition to salinisation, the groundwater in the upstream and intermediate regions was contaminated with nitrate, while groundwater in the downstream region was affected by fluoride. Calculations of ionic ratios and seawater fraction indicated that seawater intrusion was not dominant in the study area. The primary factors controlling the groundwater chemistry in Al Musanaah appear to be halite dissolution, reverse ion exchange with clay material and anthropogenic pollutants.

  11. Plan of study for the Northern Atlantic Coastal Plain Regional Aquifer System Analysis

    USGS Publications Warehouse

    Meisler, Harold

    1980-01-01

    Sediments of Cretaceous to Holocene age compose the Northern Atlantic Coastal Plain aquifer system in an area of 50,000 square miles in parts of New York, New Jersey, Delaware, Maryland, Virginia, and North Carolina. The aquifer system is a major source of water supply in the area. About 1.4 billion gallons is withdrawn from its aquifers each day. Increasing withdrawal of ground water has created or intensified several problems such as declining water levels, development of large cones of depression, saltwater intrusion, spreading of ground-water contamination, and land subsidence. The U.S. Geological Survey has begun a comprehensive study that will define the geology, hydrology, and geochemistry of the aquifer system. The effects of future utilization of the aquifer system will be determined and alternative plans for water withdrawal will be evaluated through computer simulation modeling. This report describes the objectives, organization, and work plans of the study, and describes the work to be accomplished in each U.S. Geological Survey District of the study area.

  12. Aquifers in Cretaceous rocks of the central Coastal Plain of North Carolina

    USGS Publications Warehouse

    Winner, M.D.; Lyke, W.L.

    1989-01-01

    Aquifers in rocks of Cretaceous age are the major source of groundwater for public supplies in the central Coastal Plain. These aquifers consist of sand, gravel, and limestone beds of the Peedee, Black Creek, and the upper and lower Cape Fear aquifers, each separated by a confining unit composed of clay and silt beds. The aquifers and confining units (1) rest upon crystalline basement rocks; (2) dip and thicken to the east-southeast; and (3) are overlain by younger aquifers and confining units in deposits of Quaternary and Tertiary age. The top of the uppermost aquifer, the Peedee, ranges from 122 ft above to 595 ft below sea level. The maximum thickness of all aquifers and confining units in Cretaceous rocks is more than 1,600 ft. Aquifers and confining units were defined and correlated for this report using 125 geophysical logs and accompanying drillers ' logs, water level data, and water quality information regarding chloride concentrations in water. This analysis allowed the construction of seven hydrogeologic cross sections that depict the continuity of all the aquifers and confining units. These cross sections also show water levels and chloride concentrations in water from various test intervals and describe where chloride concentration in water exceeds 250 mg/L within each aquifer. Detailed maps of each Cretaceous aquifer show altitude of its top, thickness, areas of selected sand percentages, transition zones from fresh to saltwater, and the thickness of the confining unit.

  13. Effects of 50-years unmanaged water resource in Southern Tuscany coastal plains (Italy)

    NASA Astrophysics Data System (ADS)

    Rossetto, R.; Debolini, M.; Galli, M. A.; Bonari, E.

    2012-04-01

    Southern Tuscany coastal plains show favorable conditions from the agro-pedoclimatic point of view and are characterized by a relevant touristic flux, being one of the most popular seaside resort. In such conditions, water resource is one of the main assets: disregarded water management may then lead to severe consequences for the development and growth of the socio-economic system and agro-ecosystem maintenance. During the 1960 decade, ante-II World War projects for hydropower production (i.e. the Farma-Merse scheme) were rearranged in favor of irrigation and the enhancement of crop production. Storage of about 110 Mm3 was thought to provide water for about 35000 Ha. At the end of the 70's, mass tourism began to take place in coastal areas giving rise to water access conflicts between agriculture and the touristic infrastructure. Being none of these projects realized, the increasing demand for drinking water was satisfied by tapping the Mount Amiata aquifer for 70% of the annual demand, and the remaining 30% coming from local aquifers. Due to the absence of rainfall and then of surface water flow in streams at the end of the spring and during the summer period, irrigation requirements were also satisfied by means of groundwater withdrawals. As a consequence of overdraft, aquifer salinisation started in most of the coastal areas (Regione Toscana, 1995; Bianchi et al., 2011; Scuola Superiore Sant'Anna, 2011). All this happened in the completely absence of controls on groundwater abstractions. In the early 90's, the Commissione Leon (Regione Toscana, 1991) re-analyzed the largest dam projects and presented as feasible a conjunctive use of surface water stored in artificial basins (to be built) and by planned and controlled local aquifers. Anyway, political issues and environmental concerns halted any kind of realization, so that today the largest basin in the area is private, it dates back to 1930, and it shows a reduced capacity of about 1.8 Mm3, instead than the

  14. Stratigraphic correlation of oligocene marginal marine and fluvial deposits across the middle and lower coastal plain, South Carolina

    NASA Astrophysics Data System (ADS)

    Katuna, Michael P.; Geisler, Jonathan H.; Colquhoun, Donald J.

    1997-02-01

    The age and stratigraphic relationship of the Upland Unit, which crops out at the Savannah River Site near Barnwell, South Carolina has been the focus of many recent investigations. The geological interpretation of the Upland Unit is particularly significant since it serves as the upper confining unit used in the storage of lowlevel radioactive wastes at the Savannah River Site. The age and regional extent of the unit is also important in providing an accurate geological map of the upper coastal plain. The age of the Upland Unit has been in dispute because it lacks datable material. Extensive coring and seismic studies have been conducted to investigate the occurrence and regional distribution of this stratigraphic unit. Lithologically, the Upland Unit consists of poorly sorted, clayey to silty, medium- to coarse-grained sands and gravels of fluvial origin. Similar quartz gravel deposits have been reported from the Chandler Bridge Formation near Charleston, South Carolina. These 'Upland-like' gravels are the oldest gravels of Tertiary age reported in the lower coastal plain. The Chandler Bridge Formation is interpreted as a downdip marginal marine facies of an extensive fluvial drainage system which once extended from the upper to the lower coastal plain of South Carolina. Where present, the Chandler Bridge Formation is overlain by nodular phosphate deposits of the Edisto Formation (late Oligocene to early Miocene), and underlain by the Ashley Formation of late Oligocene age. Pollen and dinoflagellate analyses conducted on sediment samples also confirm a late Chattian age for the Chandler Bridge Formation. Consequently, if quartz clasts in the Chandler Bridge Formation represent fluvial transport of Upland Unit gravels from the upper coastal plain which seems likely, then the age of the Upland Unit can be no younger than late Oligocene. Lithologic and stratigraphic analyses suggest that the Upland Unit and the Chandler Bridge Formation are correlative and represent

  15. Effects of infiltration chemistry on the mobilization potential of mercury (Hg) in soils from the New Jersey Coastal Plain

    SciTech Connect

    MacLeod, C.; Taylor, E. . Dept. of Geological and Geophysical Sciences)

    1992-01-01

    Mercury concentrations in ground water exceeding the USEPA maximum contaminant level of 2 [mu]g/l have been found in wells 60 to 100 feet deep in the Kirkwood-Cohansey Aquifer System of the New Jersey Coastal Plain. The aquifer is a sand and gravel aquifer consisting primarily of quartz with minor amounts of biotite, plagioclase feldspars and ilmenite. This is the shallowest aquifer system in the NJ Coastal Plain and is unconfined over much of central and southern NJ. Soils on these aquifer sediments are quartz-rich with poorly developed A[sub 0] and B horizons. These are weakly-buffered acid soils with a pH ranging from 4.0 to 5.5, and little or no capacity for metal retention. Mercury contaminated soils from Gloucester County, NJ were used to determine the mobilization potential of Hg by run-off solutions containing 0.02M NaCl and 0.02M CaCl[sub 2] salt solutions that approximate diluted highway de-icing salts; and by a simulated acid rain solution of pH 4.0. These experimental data are in agreement with previous studies suggesting that chlorides from de-icing salts are capable of mobilizing Hg. However, the mobilization potential of Hg in coastal plain soils attributable to acid rain is much greater (approx. 1 to 2 orders of magnitude) than that estimated for de-icing salts. These data also indicate that in NJ Coastal Plain soils Hg mobilization may be controlled by colloidal movement during an infiltration event. Mobilization of Hg by the simulated acid rain solution was found to coincide with the resuspension of Fe and Al colloids, while no colloidal movement was found with either of the salt solutions. Thus Hg sorbed to Fe and Al colloids in NJ Coastal Plain soils is more likely to be mobilized by infiltration of acidic rain water or fluctuating acidic ground water than by highway de-icing salts.

  16. Simulation of ground-water flow and movement of the freshwater-saltwater interface in the New Jersey coastal plain

    USGS Publications Warehouse

    Pope, Daryll A.; Gordon, Alison D.

    1999-01-01

    The confined aquifers of the New Jersey Coastal Plain are sands that range in thickness from 50 to 600 feet and are separated by confining units. The confining units are composed of silts and clays that range in thickness from 500 to 1,000 feet. The aquifers are recharged by precipitation on their outcrop areas. This water then flows laterally downdip and vertically to the deeper confined aquifers. The confined aquifers ultimately discharge to the Raritan and Delaware Bays and to the Atlantic Ocean. In 1988, ground-water withdrawals from confined and unconfined New Jersey Coastal Plain aquifers were approximately 345 million gallons per day, more than 75 percent of which was pumped from the confined aquifers. These withdrawals have created large cones of depression in several Coastal Plain aquifers near populated areas, particularly in Camden and Monmouth Counties. The continued decline of water levels in confined aquifers can cause saltwater intrusion, reduce stream discharge near the outcrop areas, and threaten the quality of the ground-water supply. SHARP, a quasi-three-dimensional finite-difference computer model that can simulate freshwater and saltwater flow, was used to simulate the ground-water flow system in the New Jersey Coastal Plain, including the location and movement of the freshwater-saltwater interface in nine aquifers and eight intervening confining units. The freshwater-saltwater interface is defined as the hypothetical line seaward of which the chloride concentration is equal to or greater than 10,000 milligrams per liter. Model simulations were used to estimate the location and movement of the freshwater-saltwater interface resulting from (1) eustatic sea-level changes over the past 84,000 years, (2) ground-water withdrawals from 1896 through 1988, (3) and future ground-water withdrawals from 1988 to 2040 from Coastal Plain aquifers. Simultion results showed that the location and movement of the freshwater-saltwater interface are more dependent

  17. Study of the United States coal resources. [Appalachian Plateau, Interior Basins, Gulf Coastal Plain, Rocky Mountain Basins, High Plains, North Alaska

    SciTech Connect

    Ferm, J.C.; Muthig, P.J.

    1982-09-15

    The objectives of this study were: (1) the identification of geologically significant coal resources for the United States, including Alaska; and (2) the preparation of statistically controlled tonnage estimates for each resource type. Particular emphasis was placed on the identification and description of coals in terms of seam thickness, inclination, depth of cover, discontinuities caused by faulting and igneous intrusion, and occurrence as isolated or multiseam deposits. The national resource was organized into six major coal provinces: the Appalachian Plateau, the Interior Basins, the Gulf Coastal Plain, the Rocky Mountain Basins, the High Plains, and North Alaska. Total coal tonnage for a subarea was estimated from an analysis of the cumulative coal thickness derived from borehole or surface section records and subsequently categorized in terms of seam thickness, dip, overburden, multiseam proportions, coal quality, and tonnage impacted by severe faulting and igneous intrusions. Results indicate an aggregate resource in place of 11.6 trillion tons, of which North Alaska accounts for 3.5 trillion tons of subbituminous and bituminous coal; the Rocky Mountains, 2.2 trillion tons of bituminous and subbituminous deposits; and the Gulf Coast, 3.8 trillion tons of lignites. The Appalachian Plateau and Interior Basins are estimated to contain slightly less than 1 trillion tons each of bituminous coal, and the High Plains slightly more than 0.5 trillion tons of lignite. The Appalachian Plateau and Interior Basins are estimated to contain slightly less than 1 trillion tons each, and the High Plains Province is estimated to contain a bit more than 0.5 trillion tons. The implications of the results for research on advanced mining systems are discussed. 27 figures, 25 tables.

  18. Sele coastal plain flood risk due to wave storm and river flow interaction

    NASA Astrophysics Data System (ADS)

    Benassai, Guido; Aucelli, Pietro; Di Paola, Gianluigi; Della Morte, Renata; Cozzolino, Luca; Rizzo, Angela

    2016-04-01

    Wind waves, elevated water levels and river discharge can cause flooding in low-lying coastal areas, where the water level is the interaction between wave storm elevated water levels and river flow interaction. The factors driving the potential flood risk include weather conditions, river water stage and storm surge. These data are required to obtain inputs to run the hydrological model used to evaluate the water surface level during ordinary and extreme events regarding both the fluvial overflow and storm surge at the river mouth. In this paper we studied the interaction between the sea level variation and the river hydraulics in order to assess the location of the river floods in the Sele coastal plain. The wave data were acquired from the wave buoy of Ponza, while the water level data needed to assess the sea level variation were recorded by the tide gauge of Salerno. The water stages, river discharges and rating curves for Sele river were provided by Italian Hydrographic Service (Servizio Idrografico e Mareografico Nazionale, SIMN).We used the dataset of Albanella station (40°29'34.30"N, 15°00'44.30"E), located around 7 km from the river mouth. The extreme river discharges were evaluated through the Weibull equation, which were associated with their return period (TR). The steady state river water levels were evaluated through HEC-RAS 4.0 model, developed by Hydrologic Engineering Center (HEC) of the United States Army Corps of Engineers Hydrologic Engineering Center (USACE,2006). It is a well-known 1D model that computes water surface elevation (WSE) and velocity at discrete cross-sections by solving continuity, energy and flow resistance (e.g., Manning) equation. Data requirements for HEC-RAS include topographic information in the form of a series of cross-sections, friction parameter in the form of Manning's n values across each cross-section, and flow data including flow rates, flow change locations, and boundary conditions. For a steady state sub

  19. A late Quaternary multiple paleovalley system from the Adriatic coastal plain (Biferno River, Southern Italy)

    NASA Astrophysics Data System (ADS)

    Amorosi, Alessandro; Bracone, Vito; Campo, Bruno; D'Amico, Carmine; Rossi, Veronica; Rosskopf, Carmen M.

    2016-02-01

    A buried paleovalley system, up to 2 km wide and exceeding 50 m in relief, made up of multiple cross-cutting depressions incised into the Lower Pleistocene bedrock, is reported from the central Adriatic coastal plain at the mouth of Biferno River. Through a multi-proxy approach that included geomorphological, stratigraphic, sedimentological and paleontological (benthic foraminifers, ostracods and molluscs) investigations, the facies architecture of distinct, superposed valley fills is reconstructed and their relative chronology established along a transverse profile with extremely high data density (average borehole spacing 75 m). Regional tectonic uplift appears as the major controlling factor of initial (Middle Pleistocene) river down-cutting and paleovalley formation. In contrast, glacio-eustatic fluctuations drove fluvial-system response over the last 120 ky, when valley incision was primarily induced by the last glacial base-level lowering and climatic forcing. A fragmented record of coastal and shallow-marine deposits is available for the lower paleovalley fill, which is penetrated by a limited borehole dataset. Multiple erosion phases probably related to the post-MIS 5e sea-level fall are reconstructed from the upper paleovalley fill, where a buried fluvial terrace succession is identified a few tens of meters below the ground surface. The flat surfaces of two buried fluvial terraces suggest longer-term, stepped relative sea-level fall, and are correlated with fluvial incisions that took place possibly at the MIS 5/4 transition and at the MIS 3/2 transition, respectively. A laterally extensive gravel body developed on the valley floor during the Last Glacial Maximum. During the ensuing latest Pleistocene-early Holocene sea-level rise the Biferno paleovalley was transformed into an estuary. Upstream from the maximum shoreline ingression, the vertical succession of well-drained floodplain, poorly-drained floodplain, and swamp deposits evidences increasing

  20. Management Effects on Soil Respiration in North Carolina Coastal Plain Loblolly Pine Plantations

    NASA Astrophysics Data System (ADS)

    Gavazzi, M.; McNulty, S.; Noormets, A.; Treasure, E.

    2012-12-01

    Loblolly pine is the most widely planted tree for plantation management in the southern US. In the southern coastal plain, where much of the original longleaf pine and bottomland hardwood forests have been converted to loblolly pine plantations, inland areas are commonly characterized by deep organic soils that can store up to 80 kg C m-2. Intensive management activities on these sites disturb the forest floor and soil and their impact on soil respiration rates and long term soil storage capabilities is unclear. We measured soil respiration rates in three loblolly pine plantations being managed with a combination of ditching, bedding, clearcutting, thinning and fertilization. Sites and management regimes represented a wide range of real world conditions found in managed southern US forestry plantations. Soil efflux rates along with soil temperature and moisture were measured throughout the year at four to six plots on each site and best fit relationships were developed. Annual soil respiration rates where modeled using 30-minute soil temperature and moisture measurements recorded at a centralized meteorological station on each site. Soil efflux rates were highly correlated with soil temperature and moisture, but interaction between the two effects was uncommon. Soil temperature was the primary driver of soil respiration rates, but rates were suppressed under high soil moisture content. Modeled annual soil efflux rates were higher the first two years following clearcut harvest and thinning operations, but lower two years following fertilization. Rates were lower in the gaps, where entire tree rows were removed, compared to thinned areas, especially on the unfertilized site. Results indicate that soil respiration rates can be strongly impacted by forest management practices; however, the period of increased soil CO2 efflux due to site disturbance may last only a few years.

  1. Dissolved phosphorus retention and release from a coastal plain in-stream wetland.

    PubMed

    Novak, J M; Stone, K C; Szogi, A A; Watts, D W; Johnson, M H

    2004-01-01

    Dissolved phosphorus (DP) can be released from wetlands as a result of flooding or shifts in water column concentrations. Our objectives were to determine the long-term (1460 d) DP retention and release characteristics of an in-stream wetland, and to evaluate how these characteristics respond to flooding, draining, and changes in DP concentrations. The studied in-stream wetland drains an agriculturally intensive subwatershed in the North Carolina Coastal Plain region. The wetland's DP retention and release characteristics were evaluated by measuring inflow and outflow DP concentrations, DP mass balance, and DP movement across the sediment-water column interface. Phosphorus sorption isotherms were measured to determine the sediment's equilibria P concentration (EPCo), and passive samplers were used to measure sediment pore water DP concentrations. Initially, the in-stream wetland was undersized (0.31 ha) and released 1.5 kg of DP. Increasing the in-stream wetland area to 0.67 ha by flooding resulted in more DP retention (28 kg) and low outflow DP concentrations. Draining the in-stream wetland from 0.67 to 0.33 ha caused the release of stored DP (12.1 kg). Shifts both in sediment pore water DP concentrations and sediment EPCo values corroborate the release of stored DP. Reflooding the wetland from 0.33 to 0.85 ha caused additional release of stored DP into the outflowing stream (10.9 kg). We conclude that for a time period, this in-stream wetland did provide DP retention. During other time periods, DP was released due to changes in wetland area, rainfall, and DP concentrations. PMID:14964396

  2. Carbon in Natural, Cultivated, and Restored Depressional Wetlands in the Mid-Atlantic Coastal Plain.

    PubMed

    Fenstermacher, D E; Rabenhorst, M C; Lang, M W; McCarty, G W; Needelman, B A

    2016-03-01

    Aerial extent of wetland ecosystems has decreased dramatically since precolonial times due to the conversion of these areas for human use. Wetlands provide various ecosystem services, and conservation efforts are being made to restore wetlands and their functions, including soil carbon storage. This Mid-Atlantic Regional USDA Wetland Conservation Effects Assessment Project study was conducted to evaluate the effects and effectiveness of wetland conservation practices along the Mid-Atlantic Coastal Plain. This study examined 48 wetland sites in Delaware, Maryland, Virginia, and North Carolina under natural, prior converted cropland, and 5- to 10-yr post wetland restoration states. The North Carolina sites mainly contained soils dominated by organic soil materials and therefore were analyzed separately from the rest of the sites, which primarily contained mineral soils. Soil samples were collected using the bulk density core method by horizon to a depth of 1 m and were analyzed for percent carbon. The natural wetlands were found to have significantly greater carbon stocks (21.5 ± 5.2 kg C m) than prior converted croplands (7.95 ± 1.93 kg C m; < 0.01) and restored wetlands (4.82 ± 1.13 kg C m; < 0.001). The restored and prior converted sites did not differ significantly, possibly the result of the methods used to restore the wetlands, and the relatively young age of the restored sites. Wetlands were either restored by plugging drainage structures, with minimal surface disturbance, or by scraping the surface (i.e., excavation) to increase hydroperiod. Sites restored with the scraping technique had significantly lower carbon stocks (2.70 ± 0.38 kg C m) than those restored by passive techniques (6.06 ± 1.50 kg C m; = 0.09). Therefore, techniques that involve excavation and scraping to restore hydrology appear to negatively affect C storage. PMID:27065423

  3. Overview of investigations into mercury in ground water, soils, and septage, New Jersey coastal plain

    USGS Publications Warehouse

    Barringer, J.L.; Szabo, Z.

    2006-01-01

    Since the early 1980s, investigations by health departments of eight counties in southern New Jersey, by the NJ Department of Environmental Protection (NJDEP), and subsequently by the US Geological Survey (USGS), have shown that Hg concentrations in water tapped by about 600 domestic wells exceed the maximum contaminant level (MCL) of 2 ??g/L. The wells are finished in the areally extensive unconfined Kirkwood-Cohansey aquifer system of New Jersey's Coastal Plain; background concentrations of Hg in water from this system are < 0.01 ??g/L. Evidence of contributions from point sources of Hg, such as landfills or commercial and industrial hazardous-waste sites, is lacking. During 1996-2003, the USGS collected water samples from 203 domestic, irrigation, observation, and production wells using ultraclean techniques; septage, leach-field effluent, soils, and aquifer sediments also were sampled. Elevated concentrations of NH4, B, Cl, NO3, and Na and presence of surfactants in domestic-well water indicate that septic-system effluent can affect water quality in unsewered residential areas, but neither septage nor effluent appears to be a major Hg source. Detections of hydrogen sulfide in ground water at a residential area indicate localized reducing conditions; undetectable SO4 concentrations in water from other residential areas indicate that reducing conditions, which could be conducive to Hg methylation, may be common locally. Volatile organic compounds (VOCs), mostly chlorinated solvents, also are found in ground water at the affected areas, but statistically significant associations between presence of Hg and VOCs were absent for most areas evaluated. Hg concentrations are lower in some filtered water samples than in paired unfiltered samples, likely indicating that some Hg is associated with particles or colloids. The source of colloids may be soils, which, when undisturbed, contain higher concentrations of Hg than do disturbed soils and aquifer sediments. Soil

  4. Mercury and methylmercury dynamics in a coastal plain watershed, New Jersey, USA

    USGS Publications Warehouse

    Barringer, J.L.; Riskin, M.L.; Szabo, Z.; Reilly, P.A.; Rosman, R.; Bonin, J.L.; Fischer, J.M.; Heckathorn, H.A.

    2010-01-01

    The upper Great Egg Harbor River watershed in New Jersey's Coastal Plain is urbanized but extensive freshwater wetlands are present downstream. In 2006-2007, studies to assess levels of total mercury (THg) found concentrations in unfiltered streamwater to range as high as 187 ng/L in urbanized areas. THg concentrations were <20 ng/L in streamwater in forested/wetlands areas where both THg and dissolved organic carbon concentrations tended to increase while pH and concentrations of dissolved oxygen and nitrate decreased with flushing of soils after rain. Most of the river's flow comes from groundwater seepage; unfiltered groundwater samples contained up to 177 ng/L of THg in urban areas where there is a history of well water with THg that exceeds the drinking water standard (2,000 ng/L). THg concentrations were lower (<25 ng/L) in unfiltered groundwater from downstream wetland areas. In addition to higher THg concentrations (mostly particulate), concentrations of chloride were higher in streamwater and groundwater from urban areas than in those from downstream wetland areas. Methylmercury (MeHg) concentrations in unfiltered streamwater ranged from 0.17 ng/L at a forest/wetlands site to 2.94 ng/L at an urban site. The percentage of THg present as MeHg increased as the percentage of forest + wetlands increased, but also was high in some urban areas. MeHg was detected only in groundwater <1 m below the water/sediment interface. Atmospheric deposition is presumed to be the main source of Hg to the wetlands and also may be a source to groundwater, where wastewater inputs in urban areas are hypothesized to mobilize Hg deposited to soils. ?? 2010 US Government.

  5. Digital computer simulation model of the Englishtown aquifer in the northern coastal plain of New Jersey

    USGS Publications Warehouse

    Nichols, W.D.

    1977-01-01

    Continued decline of water levels in the Englishtown aquifer, in New Jersey, has caused considerable concern regarding the ability of the aquifer to meet future yield demands. A detailed study of the capability of the aquifer to yield water entailed the use of a digital computer simulation model to evaluate aquifer and confining layer coefficients and to test alternative concepts of the hydrodynamics of the flow system. The modeled area includes about 750 square miles of the northern Coastal Plain of New Jersey and encompasses all the major centers of pumping from the Englishtown aquifer. The simulation model was calibrated by matching computed declines with historical water-level declines over the 12-year period, 1959-70. The volume of transient and steady leakage into the Englishtown aquifer from and through the adjacent confining layers equaled more than 90 percent of the total volume of water withdrawn from the aquifer between 1959 and 1970. The analytical estimate of transient leakage indicates that about 60 percent of the water withdrawn from the Englishtown between 1959 and 1970 was replaced by water released from storage in the adjacent confining beds. An additional 34 percent of the withdrawal over this time period was supported by steady leakage through the overlying confining bed from the Mount Laurel aquifer. Of the more than 30 billion gallons withdrawn from the aquifer over the 12-year period, about 2 billion gallons were obtained from storage in the aquifer. The values of aquifer and confining-layer coefficients used in the model are nearly the same as the average values obtained from field and laboratory data. (Woodard-USGS)

  6. Quaternary Sea-Level History from the US Atlantic Coastal Plain

    NASA Astrophysics Data System (ADS)

    Poirier, R. K.; Cronin, T. M.; Katz, M. E.; Browning, J. V.; Miller, K. G.; Willard, D. A.

    2014-12-01

    Analyses of emerged Quaternary paleo-shorelines and marine deposits aid in the reconstruction of environmental conditions and variability surrounding recent ice volume and sea-level histories derived from oxygen isotope records. We present preliminary results from a project designed to analyze the age, elevation, and paleoclimate history of Quaternary sediments deposited during sea level highstands along the United States Atlantic Coastal Plain (ACP) from Maryland to Florida. Prior studies have shown that, depending on the region, ACP sediments correlate with past interglacial periods corresponding to Marine Isotope Stages (MIS) 5, 7, possibly 9, and 11. Stratigraphy, marine micropaleontology, and palynology indicate at least two major marine transgressive sequences on the Delmarva Peninsula in Virginia corresponding to MIS 5a and 11, the Nassawadox Formation and Accomack beds of the Omar Formation, respectively. These depositional sequences represent sea-level positions of approximately +10m and +15m, relative to today. Despite generally corresponding to glacio-eustatic sea levels of +5-9m for MIS 5a-e (Potter & Lambeck, 2003; Kopp et al., 2009), and of +6-13m for MIS 11 (Raymo & Mitrovica, 2012), the relative sea-level positions during both interglacial periods were likely affected by glacio-isostatic adjustment in the region. Corresponding marine units and paleo-shorelines, identified by pronounced inland scarps separated by intermittent terraces on the western side of the Chesapeake Bay, are likely from MIS 5, 7, and 11. Ostracode and foraminifera assemblages identify significant environmental variability within these transgressive interglacial deposits, likely driven by relatively minor, suborbital climatic and sea-level oscillations.

  7. Microclimate and actual evapotranspiration in a humid coastal-plain environment

    NASA Astrophysics Data System (ADS)

    Dennehy, Kevin F.; McMahon, Peter B.

    1987-09-01

    Continuous hourly measurements of twelve meteorologic variables recorded during 1983 and 1984 were used to examine the microclimate and actual evapotranspiration at a low-level radioactive-waste burial site near Barnwell, South Carolina. The study area is in the Atlantic Coastal Plain of southwestern South Carolina. Monthly, daily, and hourly trends in net radiation, incoming and reflected short-wave radiation, incoming and emitted long-wave radiation, soil-heat flux, dry- and wet-bulb temperatures, soil temperatures, wind direction and speed, and precipitation were used to characterize the microclimate. Average daily air temperatures ranged from -9 to 32° Celsius during the period of study. Net radiation varied from about -27 to 251 watts m -2 and was dominated by incoming short-wave radiation throughout the year. The peak net radiation during a summer day generally occurred 2-3h before the peak vapor pressure deficit. In the winter, these peaks occurred at about the same time of day. Monthly precipitation varied from 15 to 241 mm. The Bowen ratio method was used to estimate hourly evapotranspiration, which was summed to also give daily and monthly evapotranspiration. Actual evapotranspiration varied from 0.0 to 0.7 mm h -1, 0.8-5 mm d -1, and 20-140 mm month -1 during 1983 and 1984. The maximum rate of evapotranspiration generally occurred at the same time of day as maximum net radiation, suggesting net radiation was the main driving force for evapotranspiration. Precipitation exceeded evapotranspiration during 14 months of the 2yr study period. Late fall, winter, and early spring contained the majority of these months. The maximum excess precipitation was 115 mm in February 1983.

  8. Paleoenvironmental analyses of an organic deposit from an erosional landscape remnant, Arctic Coastal Plain of Alaska

    SciTech Connect

    Eisner, W R; Bockheim, J G; Hinkel, K M; Brown, T A; Nelson, F E; Peterson, K M; Jones, B M

    2005-01-02

    The dominant landscape process on the Arctic Coastal Plain of northern Alaska is the formation and drainage of thaw lakes. Lakes and drained thaw lake basins account for approximately 75% of the modern surface expression of the Barrow Peninsula. The thaw lake cycle usually obliterates lacustrine or peat sediments from previous cycles which could otherwise be used for paleoecological reconstruction of long-term landscape and vegetation changes. Several possible erosional remnants of a former topographic surface that predates the formation of the thaw lakes have been tentatively identified. These remnants are characterized by a higher elevation, a thick organic layer with very high ground ice content in the upper permafrost, and a plant community somewhat atypical of the region. Ten soil cores were collected from one site, and one core was intensively sampled for soil organic carbon content, pollen analysis, and {sup 14}C dating. The lowest level of the organic sediments represents the earliest phase of plant growth and dates to ca. 9000 cal BP. Palynological evidence indicates the presence of mesic shrub tundra (including sedge, birch, willow, and heath vegetation); and microfossil indicators point to wetter eutrophic conditions during this period. Carbon accumulation was rapid due to high net primary productivity in a relatively nutrient-rich environment. These results are interpreted as the local response to ameliorating climate during the early Holocene. The middle Holocene portion of the record contains an unconformity, indicating that between 8200 and 4200 cal BP sediments were eroded from the site, presumably in response to wind activity during a drier period centered around 4500 cal BP. The modern vegetation community of the erosional remnant was established after 4200 cal BP, and peat growth resumed. During the late Holocene, carbon accumulation rates were greatly reduced in response to the combined effects of declining productivity associated with climatic

  9. Pre-Mesozoic terranes and the tectonic framework of the Gulf Coastal Plain

    SciTech Connect

    Thomas, W.A. . Dept. of Geological Sciences)

    1993-03-01

    Pre-Mesozoic rocks beneath the Gulf Coastal Plain reflect the late Precambrian (Pc)-Cambrian (Cb) rifted continental margin and the late Paleozoic Appalachian-Ouachita orogen (AOO). The AL promontory of Pc continental crust is bounded by a NW-striking transform margin (AL-OK transform) and a NE-striking rifted margin (southern Blue Ridge rift). Terrane accretion during the AOO differed markedly on the orthogonal adjacent sides of the AL promontory (ALp). Late Paleozoic compressional fabrics and terrane-boundary sutures, as well as extensional fabrics of the older rifted margin, influenced the geometry of Mesozoic extension and opening of the Gulf of Mexico. Along the SW side of the ALp, arc-continent collision resulted in accretion of an arc and subduction complex onto the margin of N American crust. The Ouachita allochthon includes off-shelf passive-margin rocks in an accretionary prism and synorogenic turbidites that represent a forearc basin and trench. Carbonate-shelf strata of the N American passive margin remained in place beneath the Ouachita allochthon. Along the southeast side of the ALp, passive-margin carbonate-shelf rocks are imbricated in the Appalachian thrust belt and bordered by an internal metamorphic belt of accreted terranes; both are underlain by relatively shallow Pc basement. The SE-dipping Suwannee-Wiggins suture terminates the shallow continental crust, truncates previously accreted terranes, and forms the boundary between N America and the Suwannee terrane. Mesozoic extensional structures include NE-and NW-striking fault systems. A NE-striking Triassic graben overlies the Suwannee-Wiggins suture, suggesting that Mesozoic extension used the Late Paleozoic compressional fabric of the suture. A NW-striking system of Triassic fault-bounded basins coincides with the trace of the Cb AL-OK transform fault, suggesting that the older crustal boundary controlled the location of a Mesozoic transform/transfer fault system.

  10. Transplanting native dominant plants to facilitate community development in restored coastal plain wetlands.

    SciTech Connect

    De Steven, Diane; Sharitz, Rebecca R.

    2007-12-01

    Abstract: Drained depressional wetlands are typically restored by plugging ditches or breaking drainage tiles to allow recovery of natural ponding regimes, while relying on passive recolonization from seed banks and dispersal to establish emergent vegetation. However, in restored depressions of the southeastern United States Coastal Plain, certain characteristic rhizomatous graminoid species may not recolonize because they are dispersal-limited and uncommon or absent in the seed banks of disturbed sites. We tested whether selectively planting such wetland dominants could facilitate restoration by accelerating vegetative cover development and suppressing non-wetland species. In an operational-scale project in a South Carolina forested landscape, drained depressional wetlands were restored in early 2001 by completely removing woody vegetation and plugging surface ditches. After forest removal, tillers of two rhizomatous wetland grasses (Panicum hemitomon, Leersia hexandra) were transplanted into singlespecies blocks in 12 restored depressions that otherwise were revegetating passively. Presence and cover of all plant species appearing in planted plots and unplanted control plots were recorded annually. We analyzed vegetation composition after two and four years, during a severe drought (2002) and after hydrologic recovery (2004). Most grass plantings established successfully, attaining 15%–85% cover in two years. Planted plots had fewer total species and fewer wetland species compared to control plots, but differences were small. Planted plots achieved greater total vegetative cover during the drought and greater combined cover of wetland species in both years. By 2004, planted grasses appeared to reduce cover of non-wetland species in some cases, but wetter hydrologic conditions contributed more strongly to suppression of non-wetland species. Because these two grasses typically form a dominant cover matrix in herbaceous depressions, our results indicated that

  11. Narrow endemics on coastal plains: Miocene divergence of the critically endangered genus Avellara (Compositae).

    PubMed

    Fernández-Mazuecos, M; Jiménez-Mejías, P; Martín-Bravo, S; Buide, M L; Álvarez, I; Vargas, P

    2016-07-01

    Critically endangered species representing ancient, evolutionarily isolated lineages must be given priority when allocating resources for conservation projects. Sound phylogenetic analyses and divergence time estimations are required to detect them, and studies on their population genetics, ecological requirements and breeding system are needed to understand their evolutionary history and to design efficient conservation strategies. Here we present the paradigmatic case of Avellara, a critically endangered monotypic genus of Compositae inhabiting a few swamps in the west-southwest Iberian coastal plains. Our phylogenetic and dating analyses based on nuclear (ITS) and plastid (matK) DNA sequences support a Miocene (>8.6 Ma) divergence between Avellara and closely related genera, resulting in marked morphological and ecological differentiation. We found alarmingly low levels of genetic diversity, based on AFLPs and plastid DNA sequences, and confirmed the prevalence of clonal reproduction. Species distribution modelling suggested a large macroclimatically suitable area for Avellara in the western Iberian Peninsula, but its apparently narrow microecological requirements restrict its distribution to peatlands with low-mineralised waters. Although five populations have been recorded from Spain and Portugal in the past, its current distribution may be reduced to only one population, recurrently found in the last decade but threatened by herbivory and habitat degradation. All this confirms the consideration of Avellara as a threatened species with high phylogenetic singularity, and makes it a flagship species for plant conservation in both Spain and Portugal that should be given priority in the design of in situ and ex situ conservation programmes.

  12. Age and correlation of emerged pliocene and pleistocene deposits, U.S. Atlantic Coastal Plain

    USGS Publications Warehouse

    Cronin, T. M.; Bybell, L.M.; Poore, R.Z.; Blackwelder, B. W.; Liddicoat, J.C.; Hazel, J.E.

    1984-01-01

    Paleontologic and paleomagnetic investigations were conducted on several hundred Pliocene and Pleistocene marine samples from five regions of the emerged Atlantic Coastal Plain: (1) the Delmarva Peninsula, (2) eastern Virginia, (3) central and northern North Carolina, (4) southern North Carolina and northeastern South Carolina, and (5) the Charleston area, South Carolina. Molluscan and ostracode interval and assemblage zonations, which are the primary means of regional correlation, have been calibrated using planktic biochronologic, paleomagnetic, radiometric and amino-acid recemization data. These multiple dating criteria were used to determine the age and, where possible, the duration of marine transgressive/regressive sequences. A correlation chart illustrates the age relationships of 27 formations from five regions. One important conclusion is some of the Yorktown Formation of Virginia and North Carolina (including the "Duplin" Formation), and some of the Raysor of South Carolina are late Pliocene in age. The late Pliocene Chowan River Formation of North Carolina is older than the early Pleistocene Waccamaw Formation of South Carolina, which in turn may be older than the James City Formation of North Carolina. During the last 1.0 million years, multiple marine transgressions occurred in each region, but the age of these middle and late Pleistocene formations often may differ from one area to the next. A significant result of the study is the evidence for the lack of time equivalence of formations in the five different regions; that is, the sequence of marine transgressions in one region does not necessarily correspond to that in another. This appears to be the result of differing subsidence and uplift histories, the patchiness of the depositional record, and the limitations of the dating techniques in light of the rapidity and frequency of sea-level fluctuations. ?? 1984.

  13. Prioritizing watersheds for conservation actions in the southeastern coastal plain ecoregion.

    PubMed

    Jang, Taeil; Vellidis, George; Kurkalova, Lyubov A; Boll, Jan; Hyman, Jeffrey B

    2015-03-01

    The aim of this study was to apply and evaluate a recently developed prioritization model which uses the synoptic approach to geographically prioritize watersheds in which Best Management Practices (BMPs) can be implemented to reduce water quality problems resulting from erosion and sedimentation. The model uses a benefit-cost framework to rank candidate watersheds within an ecoregion or river basin so that BMP implementation within the highest ranked watersheds will result in the most water quality improvement per conservation dollar invested. The model was developed to prioritize BMP implementation efforts in ecoregions containing watersheds associated with the USDA-NRCS Conservation Effects Assessment Project (CEAP). We applied the model to HUC-8 watersheds within the southeastern Coastal Plain ecoregion (USA) because not only is it an important agricultural area but also because it contains a well-studied medium-sized CEAP watershed which is thought to be representative of the ecoregion. The results showed that the three HUC-8 watersheds with the highest rankings (most water quality improvement expected per conservation dollar invested) were located in the southern Alabama, northern Florida, and eastern Virginia. Within these watersheds, measures of community attitudes toward conservation practices were highly ranked, and these indicators seemed to push the watersheds to the top of the rankings above other similar watersheds. The results, visualized as maps, can be used to screen and reduce the number of watersheds that need further assessment by managers and decision-makers within the study area. We anticipate that this model will allow agencies like USDA-NRCS to geographically prioritize BMP implementation efforts. PMID:25528594

  14. The effect of sea level rise on coastal plain estuaries, with examples from Chesapeake Bay

    SciTech Connect

    Colman, S.M. )

    1990-05-01

    Estuaries are geologically transitory features whose evolution depends on a delicate balance among relative sea level basin geometry, shoreline erosion, fluvial sediment discharge, littoral drift, and tidal exchange. Models of modern estuarine development require specific sea level scenarios; almost all assume a continuation of the decelerating sea level rise of the last few thousand years. However, under constant external conditions, estuaries are ephemeral because they rapidly fill with fluvial and marine sediment. The rate of filling changes with time, but only a few thousand years are required to fill most estuaries. The persistence of estuaries, therefore, requires that relative sea level rises at a rate sufficient to compensate for the inherent tendency of estuaries to fill with sediment. Coastal plain estuaries, of which Chesapeake Bay is a prime example, are often referred to as drowned river valleys. Although this description is appropriate for the first-order morphology of Chesapeake Bay, the implied passivity can be misleading, especially in the high-tidal-energy area of the bay mouth where dramatic spit progradation and channel migration have occurred in the last few thousand years. Holocene sediment accumulation rates are more irregular along the length of the estuary than most models would predict; but in general, sediment accumulation has been greater at the mouth and at the head of the bay and less along the middle reaches. If relative sea level were to stabilize, the estuary would fill with sediment from both ends within a few thousand years. Evidence for two previous generations of the bay is preserved as the estuarine fill of major fluvial valleys, demonstrating that estuarine episodes have been closely tied to cyclic sea level changes.

  15. [Reproductive phenology of three vegetation types from a coastal plain of Paraguana Penninsula, Venezuela].

    PubMed

    Lemus-Jiménez, Luis José; Ramírez, Nelson

    2002-01-01

    Reproductive phenology of 51 plant species was evaluated according to life form and vegetation types in a coastal plain of the Paraguaná Peninsula, Estado Falcón, Venezuela. Plant species distribution according to three vegetation types (herbaceous littoral, herbaceous psamophil, and mangrove area) was determined. Life form frequency was different according to vegetation type. Herbaceous littoral and herbaceous psamophil vegetation were dominated by herbaceous species; woody species were mostly frequent in the mangrove vegetation. Phenological data revealed that 14 (27.5%) plant species flower and fruit year-round; 23 (45.1%) plant species flower and fruit at the beginning of the wet season; seven (13.7%) plant species flower at the end of wet season, and seven (13.7%) more flower at the beginning of the dry season. Flowsring and fruiting phenology showed similar frequency distribution during the year; reproductive phenology was independent of life forms. Flowering and fruiting peaks occurred during the rainy season and the beginning of the dry season for trees and perennial herbs, and from one to three months later for shrubs and annual herbs. The lowest proportion of flowering and fruiting occurred before rain increase for all life forms. Flowering and fruiting phenologies were similar for the three vegetation types evaluated: flowering peak occurred during the lowest value of precipitation, three to four months after precipitation peak, and fruiting peak occurred four months later from the precipitation peak. These results suggest that flowering and fruiting phenology were not affected by life form and vegetation types. The peaks of flowering and fruiting during the lowest values of precipitation may be considered as a slow and late response to the precipitation maximum, and to the proximity between maximum and minimum of precipitation.

  16. Hydrology and chemistry of groundwater and seasonal ponds in the Atlantic Coastal Plain in Delaware, USA

    NASA Astrophysics Data System (ADS)

    Phillips, Patrick J.; Shedlock, Robert J.

    1993-01-01

    The hydrochemistry of small seasonal ponds was investigated by studying relations between ground-water and surface water in a forested Coastal Plain drainage basin. Observation of changes in the water table in a series of wells equipped with automatic water-level recorders showed that the relation between water-table configuration and basin topography changes seasonally, and particularly in response to spring recharge. Furthermore, in this study area the water table is not a subdued expression of the land surface topography, as is commonly assumed. During the summer and fall months, a water-table trough underlies sandy ridges separating the seasonal ponds, and maximum water-table altitudes prevail in the sediments beneath the dry pond bottoms. As the ponds fill with water during the winter, maximum water-table altitudes shift to the upland-margin zone adjacent to the seasonal ponds. Increases in pond stage are associated with the development of transient water-table mounds at the upland-margin wells during the spring. The importance of small local-flow systems adjacent to the seasonal ponds also is shown by the similarities in the chemistry of the shallow groundwater in the upland margin and water in the seasonal ponds. The upland margin and surface water samples have low pH (generally less than 5.0), and contain large concentrations of dissolved aluminum (generally more than 100 μg 1 -1), and low bicarbonate concentrations (2 mg l 4 or less). In contrast, the parts of the surficial aquifer that do not experience transient mounding have higher pH and larger concentrations of bicarbonate. These results suggest that an understanding of the hydrochemistry of seasonally ponded wetlands requires intensive study of the adjacent shallow groundwater-flow system.

  17. Sedimentology of paleochannels on foreland coastal plain, Judith River Formation (upper Cretaceous), southeast Alberta

    SciTech Connect

    Koster, E.H.

    1984-04-01

    The upper 90 m (295 ft) of the sub-Bearpaw Judith River Formation, continuously exposed in the badlands along the Red Deer River 185 km (115 mi) east of Calgary, is famous for the unrivaled assemblage of dinosaur fossils. Dinosaur Provincial Park presents are a rare opportunity to view the architecture of a foreland coastal-plain sequence as well as to clarify the origin and distribution of subbituminous coal zones and gas reservoirs associated with this formation across southeast Alberta. The distal reaches of paleodrainage from the developing Cordillera to the Western Interior seaway are being examined by north-south traversed across the badlands. Sharp-based paleochannel units, enclosed by rooted, olive-gray mudstone sequences that are commonly 4-6 m (13-20 ft) thick, vary between 2 end members. The first contains laterally accreted sand-mud couplets with abundant macrofloral debris, and represents cyclical, low-energy growth of point bars, possible with an estuarine influence. The second, mainly comprising cosets of large trough cross-beds with mudstone intraclasts, was formed by episodic aggradation of high-energy systems. An intermediate composite type displays evidence for an energy increase as channel sinuosity decreased. This variation in paleochannel type is attributed to alternating alluviation/rejuvenation associated with an unstable base level. Coal zones and potential reservoirs appear to be associated with the transgressive and regressive phases, respectively, of the Bearpaw coast. Amalgamation of paleochannels - marked by laterally extensive horizons of bone fragments, lithic and intraclastic gravel - is more common seaward over the axial region of the Sweetgrass arch.

  18. Preliminary delineation of salty ground water in the northern Atlantic Coastal Plain

    USGS Publications Warehouse

    Meisler, Harold

    1980-01-01

    Salty ground water underlies freshwater in the eastern part of the northern Atlantic Coastal Plain. The transition zone between freshwater and saltwater is represented in this report by a series of maps showing the depths to chloride concentrations of 250, 1,000, 10,000, and 18,000 milligrams per liter. The maps are based on chloride concentrations obtained from self-potential logs as well as from water-quality analyses. Depths to the designated chloride concentrations generally increase inland from the coast except in New Jersey where they are greatest along the coast and in North Carolina where depths to the 10,000 and 18,000 milligrams per liter concentrations are greatest beneath Pamlico Sound. The transition zone between 250 and 18,000 milligrams per liter of chloride is generally 1,500 to 2,300 feet thick except in part of North Carolina, where it is less than 1,000 feet. Depths to 250 and 1,000 milligrams per liter of chloride are probably controlled by the natural flow pattern of fresh ground water. Areas where these concentrations are relatively shallow generally coincide with areas of natural ground-water discharge. Depths to 10,000 and 18,000 milligrams per liter of chloride, and the occurrence offshore of ground water that is fresher than seawater, is attributed to long-term hydrologic conditions during which sea level fluctuations of a few hundred feet recurred several times. The origin of ground water that is saltier than seawater is attributed to the leaching of evaporitic strata beneath the Continental Shelf and Slope followed by westward movement of the brines during periods of sea-level rise.

  19. Trends and transformation of nutrients and pesticides in a Coastal Plain aquifer system, United States

    USGS Publications Warehouse

    Denver, J.M.; Tesoriero, A.J.; Barbaro, J.R.

    2010-01-01

    Four local-scale sites in areas with similar corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] agriculture were studied to determine the effects of different hydrogeologic settings of the Northern Atlantic Coastal Plain (NACP) on the transport of nutrients and pesticides in groundwater. Settings ranged from predominantly well-drained soils overlying thick, sandy surficial aquifers to predominantly poorly drained soils with complex aquifer stratigraphy and high organic matter content. Apparent age of groundwater, dissolved gases, N isotopes, major ions, selected pesticides and degradates, and geochemical environments in groundwater were studied. Agricultural chemicals were the source of most dissolved ions in groundwater. Specific conductance was strongly correlated with reconstructed nitrate (the sum of N in nitrate and N gas) (R2 = 0.81, p < 0.0001), and is indicative of the relative degree of agricultural effects on groundwater. Trends in nitrate were primarily related to changes in manure and fertilizer use at the well-drained sites where aquifer conditions were consistently oxic. Nitrate was present in young groundwater but completely removed over time through denitrification at the poorly drained sites where there were variations in chemical input and in geochemical environment. Median concentrations of atrazine (6-chloro-N-ethyl-N'-(1- methylethyl)-1,3,5-triazine-2,4-diamine), metolachlor (2-chloro-N-(2-ethyl-6- methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide), and some of their common degradates were higher at well-drained sites than at poorly drained sites, with concentrations of degradates generally higher than those of the parent compounds at all sites. An increase in the percentage of deethylatrazine to total atrazine over time at one well-drained site may be related to changes in manure application. Copyright ?? 2010 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  20. Comparison of fish and macroinvertebrate bioassessments from South Carolina coastal plain streams

    SciTech Connect

    Paller, M.H.

    1999-12-03

    Stream bioassessments are often based on a single taxonomic assemblage, such as fishes or macroinvertebrates, with the assumption that this assemblage is representative of other assemblages. However, ecological and physiological differences between taxonomic groups may cause different responses to disturbance and result in different assessment results. In this study, fish and macroinvertebrate bioassessments were conducted concurrently in South Carolina coastal plain streams and compared on the basis of precision, sensitivity, accuracy, and agreement. Fish and macroinvertebrate data were evaluated with previously developed multimetric indices including a modified Index of Biotic Integrity (IBI) based on electrofishing data and a benthic macroinvertebrate multimetric index (HDMI) based on data collected with Hester-Dendy artificial substrates. Benthic macroinvertebrates were also collected from natural substrates for comparative purposes. The IBI was more precise than the HDMI but the average difference between disturbed and reference sites was greater for the HDMI, resulting in equal sensitivity (i.e., ability to measure disturbance in relation to index variability). Regression of the HDMI on the IBI was significant (P{lt}0.0001) but moderate (R2 of 0.39). Agreement between indices was strong for highly disturbed sites but weak for slightly and moderately disturbed sites. Ordination of taxonomic data indicated that fish and macroinvertebrates responded differently to some disturbances regardless of whether macroinvertebates were collected from Hester-Dendy samplers or natural substrates. Disagreement between macroinvertebrate and fish assessments at moderately disturbed sites implies that biotic integrity cannot always be adequately evaluated from a single taxonomic group. Identification of disturbed sites was most accurate when HDMI and IBI results were combined. To improve the accuracy of stream bioassessments, future research should emphasize methods for cost

  1. Physiological diversity and distributions of heterotrophic bacteria in deep cretaceous sediments of the Atlantic coastal plain

    SciTech Connect

    Fredrickson, J.K.; Zachara, J.M.; Li, S.W.; Brockman, F.J.; Simmons, M.A. ); Balkwill, D.L. )

    1991-02-01

    A series of 23 intact core segments was obtained from two distinct deep subsurface geological formations, the Middendorf and the Cape Fear formations, underlying the southeastern coastal plain of South Carolina. Aerobic chemoheterotrophic bacteria were enumerated on a dilute medium, and populations ranged from 3.1 to 6.4 log CFU g of sediment[sup [minus]1] in the Middendorf cores and from below detection to 4.3 log CFU g[sup [minus]1] in the Cape Fear cores. A total of 198 morphologically distinct colony types were isolated, purified, and subjected to 108 different physiological measurements. The isolates from the two formations were distinct as were those in different core samples from the same formation. Cluster analysis revealed 21 different biotypes based on similarities of 75% or higher in response patterns to 21 physiological assays. One biotype contained 57 of the subsurface isolates, 10 biotypes contained 5 or more isolates, and the remainder had 4 or fewer. The organic compounds that were most commonly metabolized by the subsurface bacteria included Tween 40 and [beta]-hydroxybutyric acid. Organic acids, in general, were also commonly metabolized by the subsurface bacteria. Isolates from the Cape Fear core segments were capable of metabolizing a higher percentage of the substrates than were bacteria isolated from the Middendorf formation. Although the heterogeneous distributions of bacteria in deep subsurface sediments may make it difficult to use aquifer microcosms to predict in situ biotransformation rates, the diversity of the physiological properties of these organisms offers promise for in situ remediation of contaminants.

  2. Mesozoic basin development beneath the southeastern US coastal plain: evidence from new COCORP profiling

    SciTech Connect

    McBride, J.H.; Nelson, K.D.; Arnow, J.A.; Oliver, J.E.; Brown, L.D.; Kaufman, S.

    1985-01-01

    New COCORP profiling on the Georgia coastal plain indicates that the Triassic/Early Jurassic South Georgia basin is a composite feature, which includes several large half-grabens separated by intervening regions where the Triassic/Early Jurassic section is much thinner. Two half-grabens imaged on the profiles have apparent widths of 125 and 40 km, and at their deepest points contain about 5 km of basin fill. Both basins are bounded on their south flanks by major normal faults that dip moderately steeply toward the north, and are disrupted internally by subsidiary normal faults within the basin fill sequences. The orientation of the main basin-bounding faults suggests that they might have reactivated Paleozoic south-vergent structures formed on the south side of the Alleghenian suture. Evolution of the South Georgia basin appears to follow a model of initial, rapid rifting followed by flexural subsidence. The major episode of normal faulting, and hence extension, within the South Georgia basin occurred prior to extrusion of an areally extensive sequence of Early Jurassic basalt flows. This sequence is traceable across most of the width of the South Georgia basin in western Georgia, and may extend as far east as offshore South Carolina. Jurassic strata above the basalt horizon are notably less faulted and accumulated within a broadly subsiding basin that thins both to the north and south. The occurrence of the basalt relatively late in the rift sequence supports the hypothesis that the southeastern US may have been a major area of incipient spreading after Pangea had begun to separate.

  3. Assessing Landscape Change and Processes of Recurrence, Replacement, and Recovery in the Southeastern Coastal Plains, USA

    NASA Astrophysics Data System (ADS)

    Drummond, Mark A.; Stier, Michael P.; Auch, Roger F.; Taylor, Janis L.; Griffith, Glenn E.; Riegle, Jodi L.; Hester, David J.; Soulard, Christopher E.; McBeth, Jamie L.

    2015-11-01

    The processes of landscape change are complex, exhibiting spatial variability as well as linear, cyclical, and reversible characteristics. To better understand the various processes that cause transformation, a data aggregation, validation, and attribution approach was developed and applied to an analysis of the Southeastern Coastal Plains (SECP). The approach integrates information from available national land-use, natural disturbance, and land-cover data to efficiently assess spatially-specific changes and causes. Between 2001 and 2006, the processes of change affected 7.8 % of the SECP but varied across small-scale ecoregions. Processes were placed into a simple conceptual framework to explicitly identify the type and direction of change based on three general characteristics: replacement, recurrence, and recovery. Replacement processes, whereby a land use or cover is supplanted by a new land use, including urbanization and agricultural expansion, accounted for approximately 15 % of the extent of change. Recurrent processes that contribute to cyclical changes in land cover, including forest harvest/replanting and fire, accounted for 83 %. Most forest cover changes were recurrent, while the extents of recurrent silviculture and forest replacement processes such as urbanization far exceeded forest recovery processes. The total extent of landscape recovery, from prior land use to natural or semi-natural vegetation cover, accounted for less than 3 % of change. In a region of complex change, increases in transitory grassland and shrubland covers were caused by large-scale intensive plantation silviculture and small-scale activities including mining reclamation. Explicit identification of the process types and dynamics presented here may improve the understanding of land-cover change and landscape trajectory.

  4. Assessing Landscape Change and Processes of Recurrence, Replacement, and Recovery in the Southeastern Coastal Plains, USA.

    PubMed

    Drummond, Mark A; Stier, Michael P; Auch, Roger F; Taylor, Janis L; Griffith, Glenn E; Riegle, Jodi L; Hester, David J; Soulard, Christopher E; McBeth, Jamie L

    2015-11-01

    The processes of landscape change are complex, exhibiting spatial variability as well as linear, cyclical, and reversible characteristics. To better understand the various processes that cause transformation, a data aggregation, validation, and attribution approach was developed and applied to an analysis of the Southeastern Coastal Plains (SECP). The approach integrates information from available national land-use, natural disturbance, and land-cover data to efficiently assess spatially-specific changes and causes. Between 2001 and 2006, the processes of change affected 7.8% of the SECP but varied across small-scale ecoregions. Processes were placed into a simple conceptual framework to explicitly identify the type and direction of change based on three general characteristics: replacement, recurrence, and recovery. Replacement processes, whereby a land use or cover is supplanted by a new land use, including urbanization and agricultural expansion, accounted for approximately 15% of the extent of change. Recurrent processes that contribute to cyclical changes in land cover, including forest harvest/replanting and fire, accounted for 83%. Most forest cover changes were recurrent, while the extents of recurrent silviculture and forest replacement processes such as urbanization far exceeded forest recovery processes. The total extent of landscape recovery, from prior land use to natural or semi-natural vegetation cover, accounted for less than 3% of change. In a region of complex change, increases in transitory grassland and shrubland covers were caused by large-scale intensive plantation silviculture and small-scale activities including mining reclamation. Explicit identification of the process types and dynamics presented here may improve the understanding of land-cover change and landscape trajectory. PMID:26163198

  5. Assessing landscape change and processes of recurrence, replacement, and recovery in the Southeastern Coastal Plains, USA

    USGS Publications Warehouse

    Drummond, Mark A.; Stier, Michael P.; Auch, Roger F.; Taylor, Janis; Griffith, Glenn E.; Hester, David J.; Riegle, Jodi L.; Soulard, Christopher E.; McBeth, Jamie L.

    2015-01-01

    The processes of landscape change are complex, exhibiting spatial variability as well as linear, cyclical, and reversible characteristics. To better understand the various processes that cause transformation, a data aggregation, validation, and attribution approach was developed and applied to an analysis of the Southeastern Coastal Plains (SECP). The approach integrates information from available national land-use, natural disturbance, and land-cover data to efficiently assess spatially-specific changes and causes. Between 2001 and 2006, the processes of change affected 7.8 % of the SECP but varied across small-scale ecoregions. Processes were placed into a simple conceptual framework to explicitly identify the type and direction of change based on three general characteristics: replacement, recurrence, and recovery. Replacement processes, whereby a land use or cover is supplanted by a new land use, including urbanization and agricultural expansion, accounted for approximately 15 % of the extent of change. Recurrent processes that contribute to cyclical changes in land cover, including forest harvest/replanting and fire, accounted for 83 %. Most forest cover changes were recurrent, while the extents of recurrent silviculture and forest replacement processes such as urbanization far exceeded forest recovery processes. The total extent of landscape recovery, from prior land use to natural or semi-natural vegetation cover, accounted for less than 3 % of change. In a region of complex change, increases in transitory grassland and shrubland covers were caused by large-scale intensive plantation silviculture and small-scale activities including mining reclamation. Explicit identification of the process types and dynamics presented here may improve the understanding of land-cover change and landscape trajectory.

  6. Microclimate and actual evapotranspiration in a humid coastal-plain environment

    USGS Publications Warehouse

    Dennehy, K.F.; McMahon, P.B.

    1987-01-01

    Continuous hourly measurements of twelve meteorologic variables recorded during 1983 and 1984 were used to examine the microclimate and actual evapotranspiration at a low-level radioactive-waste burial site near Barnwell, South Carolina. The study area is in the Atlantic Coastal Plain of southwestern South Carolina. Monthly, daily, and hourly trends in net radiation, incoming and reflected short-wave radiation, incoming and emitted long-wave radiation, soil-heat flux, dry- and wet-bulb temperatures, soil temperatures, wind direction and speed, and precipitation were used to characterize the microclimate. Average daily air temperatures ranged from -9 to 32?? Celsius during the period of study. Net radiation varied from about -27 to 251 watts m-2 and was dominated by incoming short-wave radiation throughout the year. The peak net radiation during a summer day generally occurred 2-3h before the peak vapor pressure deficit. In the winter, these peaks occurred at about the same time of day. Monthly precipitation varied from 15 to 241 mm. The Bowen ratio method was used to estimate hourly evapotranspiration, which was summed to also give daily and monthly evapotranspiration. Actual evapotranspiration varied from 0.0 to 0.7 mm h-1, 0.8-5 mm d-1, and 20-140 mm month-1 during 1983 and 1984. The maximum rate of evapotranspiration generally occurred at the same time of day as maximum net radiation, suggesting net radiation was the main driving force for evapotranspiration. Precipitation exceeded evapotranspiration during 14 months of the 2yr study period. Late fall, winter, and early spring contained the majority of these months. The maximum excess precipitation was 115 mm in February 1983. ?? 1987.

  7. Prioritizing Watersheds for Conservation Actions in the Southeastern Coastal Plain Ecoregion

    NASA Astrophysics Data System (ADS)

    Jang, Taeil; Vellidis, George; Kurkalova, Lyubov A.; Boll, Jan; Hyman, Jeffrey B.

    2015-03-01

    The aim of this study was to apply and evaluate a recently developed prioritization model which uses the synoptic approach to geographically prioritize watersheds in which Best Management Practices (BMPs) can be implemented to reduce water quality problems resulting from erosion and sedimentation. The model uses a benefit-cost framework to rank candidate watersheds within an ecoregion or river basin so that BMP implementation within the highest ranked watersheds will result in the most water quality improvement per conservation dollar invested. The model was developed to prioritize BMP implementation efforts in ecoregions containing watersheds associated with the USDA-NRCS Conservation Effects Assessment Project (CEAP). We applied the model to HUC-8 watersheds within the southeastern Coastal Plain ecoregion (USA) because not only is it an important agricultural area but also because it contains a well-studied medium-sized CEAP watershed which is thought to be representative of the ecoregion. The results showed that the three HUC-8 watersheds with the highest rankings (most water quality improvement expected per conservation dollar invested) were located in the southern Alabama, northern Florida, and eastern Virginia. Within these watersheds, measures of community attitudes toward conservation practices were highly ranked, and these indicators seemed to push the watersheds to the top of the rankings above other similar watersheds. The results, visualized as maps, can be used to screen and reduce the number of watersheds that need further assessment by managers and decision-makers within the study area. We anticipate that this model will allow agencies like USDA-NRCS to geographically prioritize BMP implementation efforts.

  8. Physiological diversity and distributions of heterotrophic bacteria in deep cretaceous sediments of the atlantic coastal plain.

    PubMed

    Fredrickson, J K; Balkwill, D L; Zachara, J M; Li, S M; Brockman, F J; Simmons, M A

    1991-02-01

    A series of 23 intact core segments was obtained from two distinct deep subsurface geological formations, the Middendorf and the Cape Fear formations, underlying the southeastern coastal plain of South Carolina. The Middendorf formation in this region consists of permeable, saturated, sandy sediments; the Cape Fear formation consists mainly of less permeable sediments. The core segments were separated by vertical distances ranging from several centimeters to 48 m. Aerobic chemoheterotrophic bacteria were enumerated on a dilute medium, and populations ranged from 3.1 to 6.4 log CFU g of sediment in the Middendorf cores and from below detection to 4.3 log CFU g in the Cape Fear cores. A total of 198 morphologically distinct colony types were isolated, purified, and subjected to 108 different physiological measurements. The isolates from the two formations were distinct (i.e., they produced substantially different response patterns to the various physiological measurements), as were those in different core samples from the same formation. Cluster analysis revealed 21 different biotypes based on similarities of 75% or higher in response patterns to 21 physiological assays. One biotype contained 57 (29%) of the subsurface isolates, 10 biotypes contained 5 or more isolates, and the remainder had 4 or fewer. The organic compounds that were most commonly metabolized by the subsurface bacteria included Tween 40 (85%) and beta-hydroxybutyric acid (60%). Organic acids, in general, were also commonly metabolized by the subsurface bacteria. Isolates from the Cape Fear core segments were capable of metabolizing a higher percentage of the substrates than were bacteria isolated from the Middendorf formation. Although the heterogeneous distributions of bacteria in deep subsurface sediments may make it difficult to use aquifer microcosms to predict in situ biotransformation rates, the diversity of the physiological properties of these organisms offers promise for in situ remediation

  9. Distribution and ecology of campylobacters in coastal plain streams (Georgia, United States of America).

    PubMed

    Vereen, Ethell; Lowrance, R Richard; Cole, Dana J; Lipp, Erin K

    2007-03-01

    Campylobacter is the leading cause of bacterium-associated diarrhea in the United States and most developed countries. While this disease is considered a food-borne disease, many clinical cases cannot be linked to a food source. In rural and agrarian areas environmental transmission may be an important factor contributing to case loads. Here we investigated the waterborne prevalence of campylobacters in a mixed-use rural watershed in the coastal plain of southern Georgia (United States). Six sites representing various degrees of agricultural and human influence were surveyed biweekly to monthly for 1 year for the presence of culturable thermophilic campylobacters and other measures of water quality. Campylobacters were frequently present in agriculture- and sewage-impacted stretches of streams. The mean campylobacter counts and overall prevalence were highest downstream from a wastewater treatment plant that handled both human and poultry slaughterhouse waste (

  10. Effects of flooding and drought on water quality in Gulf Coastal Plain streams in Georgia.

    PubMed

    Golladay, Stephen W; Battle, Juliann

    2002-01-01

    Since 1994, water-quality constituents have been measured monthly in three adjacent Coastal Plain watersheds in southwestern Georgia. During 1994, rainfall was 650 mm above annual average and the highest flows on record were observed. From November 1998 through November 2000, 19 months had below average rainfall. Lowest flows on record were observed during the summer of 2000. The watersheds are human-dominated with row-crop agriculture and managed forestlands being the major land uses. However, one watershed (Chickasawhatchee Creek) had 10 to 13% less agriculture and greater wetland area, especially along the stream. Suspended particles, dissolved organic carbon, NH4-N, and soluble reactive phosphorus concentrations were greater during wet and flood periods compared with dry and drought periods for each stream. Regional hydrologic conditions had little effect on NO3-N or dissolved inorganic carbon. Chickasawhatchee Creek had significantly lower suspended sediment and NO3-N concentrations and greater organic and inorganic carbon concentrations, reflecting greater wetland area and stronger connection to a regional aquifer system. Even though substantial human land use occurred within all watersheds, water quality was generally good and can be attributed to low stream drainage density and relatively intact floodplain forests. Low drainage density minimizes surface run-off into streams. Floodplain forests reduce nonpoint-source pollutants through biological and physical absorption. In addition to preserving water quality, floodplain forests provide important ecological functions through the export of nutrients and organic carbon to streams. Extreme low flows may be disruptive to aquatic life due to both the lack of water and to the scarcity of biologically important materials originating from floodplain forests.

  11. Arsenic in New Jersey Coastal Plain streams, sediments, and shallow groundwater: effects from different geologic sources and anthropogenic inputs on biogeochemical and physical mobilization processes

    USGS Publications Warehouse

    Barringer, Julia L.; Reilly, Pamela A.; Eberl, Dennis D.; Mumford, Adam C.; Benzel, William M.; Szabo, Zoltan; Shourds, Jennifer L.; Young, Lily Y.

    2013-01-01

    With a history of agriculture in the New Jersey Coastal Plain, anthropogenic inputs of As, such as residues from former pesticide applications in soils, can amplify any geogenic As in runoff. Such inputs contribute to an increased total As load to a stream at high stages of flow. As a result of yet another anthropogenic influence, microbes that reduce and mobilize As beneath the streambeds are stimulated by inputs of dissolved organic carbon (DOC). Although DOC is naturally occurring, anthropogenic contributions from wastewater inputs may deliver increased levels of DOC to subsurface soils and ultimately groundwater. Arsenic concentrations may increase with the increases in pH of groundwater and stream water in developed areas receiving wastewater inputs, as As mobilization caused by pH-controlled sorption and desorption reactions are likely to occur in waters of neutral or alkaline pH (for example, Nimick and others, 1998; Barringer and others, 2007b). Because of the difference in As content of the geologic materials in the two sub-provinces of the Coastal Plain, the amount of As that is mobile in groundwater and stream water is, potentially, substantially greater in the Inner Coastal Plain than in the Outer Coastal Plain. In turn, streams within the Inner and Outer Coastal Plain can receive substantially more As in groundwater discharge from developed areas than from environments where DOC appears to be of natural origin.

  12. The role of strong earthquakes and tsunami in the Late Holocene evolution of the Fortore River coastal plain (Apulia, Italy): A synthesis

    NASA Astrophysics Data System (ADS)

    Mastronuzzi, Giuseppe; Sansò, Paolo

    2012-02-01

    Morphological analysis of the Fortore River coastal plain and the Lesina Lake coastal barrier integrated with radiocarbon age data indicates that the evolution of the coastal landscape has been strongly affected by a number of strong earthquakes and related tsunamis which occurred during the last 3000 years. The first seismic event struck this coastal area in the V century BC. It produced strong erosion of the Fortore River coastal plain and significant emersion of Punta delle Pietre Nere, as well as the large tsunami responsible for the development of the Sant'Andrea washover fan. The second event occurred in 493 AD; it induced severe erosion of the Fortore River coastal plain and triggered the large tsunami that hit the Lesina Lake coastal barrier, producing the Foce Cauto washover fan. Then later in 1627, an earthquake was responsible for the further coseismic uplift of Punta delle Pietre Nere, the subsidence of Lesina village area and the development of a tsunami which produced two washover fans. Morphological analysis points out that seismic events strong enough to control the morphological evolution of local coastal landscapes show a statistical return period of about 1000 years. These major events produced important coseismic vertical movements and large tsunamis. However, the correct identification of the tectonic structure responsible for the generation of these strong earthquakes is still an unsolved problem.

  13. Accuracy assessment, using stratified plurality sampling, of portions of a LANDSAT classification of the Arctic National Wildlife Refuge Coastal Plain

    NASA Technical Reports Server (NTRS)

    Card, Don H.; Strong, Laurence L.

    1989-01-01

    An application of a classification accuracy assessment procedure is described for a vegetation and land cover map prepared by digital image processing of LANDSAT multispectral scanner data. A statistical sampling procedure called Stratified Plurality Sampling was used to assess the accuracy of portions of a map of the Arctic National Wildlife Refuge coastal plain. Results are tabulated as percent correct classification overall as well as per category with associated confidence intervals. Although values of percent correct were disappointingly low for most categories, the study was useful in highlighting sources of classification error and demonstrating shortcomings of the plurality sampling method.

  14. A conceptual framework and monitoring strategy for movement of saltwater in the coastal plain aquifer system of Virginia

    USGS Publications Warehouse

    Mcfarland, E. Randolph

    2015-09-04

    Some aspects of observation-well construction and sampling are of particular importance to monitoring saltwater movement in the Virginia Coastal Plain aquifer system. Observation wells should feature screened intervals generally of no more than 10 feet that isolate distinct parts of the aquifer, and be thoroughly developed for removal of drilling fluid and introduced water. Presample purging should fully displace stratified saltwater in the well casing upward to the pump. Stable flow should be maintained as field parameters are measured and sample containers are filled with filtered water isolated from the atmosphere and unaffected by surface temperature. Groundwater samples from both upconing and lateral-intrusion obse

  15. Uranium disequilibrium as a hydrological aid in studying the salinization processes in the Southeastern Coastal Plain of Israel.

    PubMed

    Avisar, D; Kronfeld, J

    2009-01-01

    Saline waters, of unknown origin, have been encountered in the basal portions of the phreatic Coastal Plain aquifer of Israel. (234)U/(238)U disequilibrium was used to trace their origin to the evaporate layers within the Saqiye aquiclude, the most saline, and the warmest (up to 42 degrees C) waters are also those that have the highest uranium concentrations combined with low (234)U/(238)U activity ratios, derived as the ascending brines traverse underlying uranium-rich Senonian phosphorites, in secular equilibrium along fault conduits.

  16. A conceptual framework and monitoring strategy for movement of saltwater in the coastal plain aquifer system of Virginia

    USGS Publications Warehouse

    Mcfarland, E. Randolph

    2015-01-01

    Some aspects of observation-well construction and sampling are of particular importance to monitoring saltwater movement in the Virginia Coastal Plain aquifer system. Observation wells should feature screened intervals generally of no more than 10 feet that isolate distinct parts of the aquifer, and be thoroughly developed for removal of drilling fluid and introduced water. Presample purging should fully displace stratified saltwater in the well casing upward to the pump. Stable flow should be maintained as field parameters are measured and sample containers are filled with filtered water isolated from the atmosphere and unaffected by surface temperature. Groundwater samples from both upconing and lateral-intrusion obse

  17. Upper Cretaceous sequences and sea-level history, New Jersey Coastal Plain

    USGS Publications Warehouse

    Miller, K.G.; Sugarman, P.J.; Browning, J.V.; Kominz, M.A.; Olsson, R.K.; Feigenson, M.D.; Hernandez, J.C.

    2004-01-01

    We developed a Late Cretaceous sealevel estimate from Upper Cretaceous sequences at Bass River and Ancora, New Jersey (ODP [Ocean Drilling Program] Leg 174AX). We dated 11-14 sequences by integrating Sr isotope and biostratigraphy (age resolution ??0.5 m.y.) and then estimated paleoenvironmental changes within the sequences from lithofacies and biofacies analyses. Sequences generally shallow upsection from middle-neritic to inner-neritic paleodepths, as shown by the transition from thin basal glauconite shelf sands (transgressive systems tracts [TST]), to medial-prodelta silty clays (highstand systems tracts [HST]), and finally to upper-delta-front quartz sands (HST). Sea-level estimates obtained by backstripping (accounting for paleodepth variations, sediment loading, compaction, and basin subsidence) indicate that large (>25 m) and rapid (???1 m.y.) sea-level variations occurred during the Late Cretaceous greenhouse world. The fact that the timing of Upper Cretaceous sequence boundaries in New Jersey is similar to the sea-level lowering records of Exxon Production Research Company (EPR), northwest European sections, and Russian platform outcrops points to a global cause. Because backstripping, seismicity, seismic stratigraphic data, and sediment-distribution patterns all indicate minimal tectonic effects on the New Jersey Coastal Plain, we interpret that we have isolated a eustatic signature. The only known mechanism that can explain such global changes-glacio-eustasy-is consistent with foraminiferal ??18O data. Either continental ice sheets paced sea-level changes during the Late Cretaceous, or our understanding of causal mechanisms for global sea-level change is fundamentally flawed. Comparison of our eustatic history with published ice-sheet models and Milankovitch predictions suggests that small (5-10 ?? 106 km3), ephemeral, and areally restricted Antarctic ice sheets paced the Late Cretaceous global sea-level change. New Jersey and Russian eustatic estimates

  18. Microbial Responses to Forest Management in the Western Gulf Coastal Plain, USA

    NASA Astrophysics Data System (ADS)

    Foote, J. A.; Boutton, T. W.; Scott, D. A.

    2013-12-01

    to the more severe harvest treatments; however, while TN was significantly impacted by harvest and varied over time, SOC varied only with time. Temporal variations in SMB-C and -N, TN, and SOC were correlated with temperature, precipitation, and volumetric soil moisture. Data suggest that forest harvest practices that minimize removal of above-ground biomass will favor soil N retention and the maintenance of the SMB pool. Since N limits tree growth in the sandy soils of the western Gulf Coastal Plain, and because SMB plays a key role in N mineralization, harvest practices that favor N retention and SMB will ensure the productivity of future rotations.

  19. Seasonal variability of microbial use of dissolved organic matter in Coastal Plain headwater streams

    NASA Astrophysics Data System (ADS)

    Hosen, J. D.; Febria, C. M.; Palmer, M.

    2013-12-01

    At the interface between land and water, headwater streams are conduits for a globally relevant amount of dissolved organic matter (DOM). Headwater systems act as more than pipes, but rather as sites where substantial DOM processing by heterotrophic microbial communities are known to occur. The amount of DOM processed by microorganisms has been shown to be related to the composition of the organic matter source. Other factors are also important to varying degrees, including the availability of inorganic nutrients such as nitrogen and phosphorus, and the activity and composition of the microbial community itself. Despite a widespread appreciation of microbial DOM cycling in headwaters, empirical studies that address the interaction of these factors at the watershed scale are needed to help fully understand and predict DOM processing across large environmental gradients, especially in the face of climate change. To address this need, we studied several properties of DOM and microbial communities in Coastal Plain headwater streams of Maryland, USA. Baseflow stream water samples were collected from 8 sites on a quarterly basis from November 2011 through Feburary 2013. Streamwater was filtered to 0.2 μm and a downstream common inoculum was added to each replicate. DOM bioavailability was determined by measuring non-purgeable organic carbon concentration before and after a 28 day incubation at 20 degrees Celsius. Other measurements collected on unamended stream water included DOM fluorescence spectroscopy, nitrogen species, ortho-phosphate, and extracellular enzyme activity (EEA). The most important factors related to DOM bioavailability changed across seasons. DOM bioavailability was positively related to fluorescence index values, indicating greater bioavailability of autochthonous material. Bioavailability also increased with increasing nitrogen concentrations, indicating that nitrogen was a limiting resource for heterotrophic microbes in the streams studied. DOM

  20. Assessing coastal plain wetland composition using advanced spaceborne thermal emission and reflection radiometer imagery

    NASA Astrophysics Data System (ADS)

    Pantaleoni, Eva

    Establishing wetland gains and losses, delineating wetland boundaries, and determining their vegetative composition are major challenges that can be improved through remote sensing studies. We used the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) to separate wetlands from uplands in a study of 870 locations on the Virginia Coastal Plain. We used the first five bands from each of two ASTER scenes (6 March 2005 and 16 October 2005), covering the visible to the short-wave infrared region (0.52-2.185mum). We included GIS data layers for soil survey, topography, and presence or absence of water in a logistic regression model that predicted the location of over 78% of the wetlands. While this was slightly less accurate (78% vs. 86%) than current National Wetland Inventory (NWI) aerial photo interpretation procedures of locating wetlands, satellite imagery analysis holds great promise for speeding wetland mapping, lowering costs, and improving update frequency. To estimate wetland vegetation composition classes, we generated a classification and regression tree (CART) model and a multinomial logistic regression (logit) model, and compared their accuracy in separating woody wetlands, emergent wetlands and open water. The overall accuracy of the CART model was 73.3%, while for the logit model was 76.7%. The CART producer's accuracy of the emergent wetlands was higher than the accuracy from the multinomial logit (57.1% vs. 40.7%). However, we obtained the opposite result for the woody wetland category (68.7% vs. 52.6%). A McNemar test between the two models and NWI maps showed that their accuracies were not statistically different. We conducted a subpixel analysis of the ASTER images to estimate canopy cover of forested wetlands. We used top-of-atmosphere reflectance from the visible and near infrared bands, Delta Normalized Difference Vegetation Index, and a tasseled cap brightness, greenness, and wetness in linear regression model with canopy

  1. Estimating Cleanup Times for Organic Contaminants in Shallow Coastal Plain Aquifers

    NASA Astrophysics Data System (ADS)

    Chapelle, F. H.; Widdowson, M. A.; Casey, C.

    2001-05-01

    Monitored natural attenuation (MNA) can be a cost-effective strategy for restoring contaminated aquifer systems either as a stand-alone technology or in combination with other engineered remedial actions. However, USEPA guidance specifically requires MNA to achieve site-specific cleanup objectives "within a reasonable time frame" (USEPA, 1999). Thus, it is necessary to provide estimates of cleanup times whenever MNA is proposed as part of a cleanup strategy. This problem can be approached in terms of a mass-balance in which rates of contaminant delivery to the environment (dissolution of NAPL, desorption etc.) are quantitatively compared to rates of contaminant destruction (principally biodegradation). Because of the complex interaction of contaminant sources and sinks, and because these factors operate within the context of dynamic ground-water systems, solutions to this problem generally requires the use of solute-transport models. This paper outlines a methodology for estimating cleanup times associated with MNA as a stand-alone remedial strategy and in conjunction with source-area removal using the numerical model Sequential Electron Acceptor Model for 3D transport (SEAM3D). The code incorporates physical transport, retardation and intrinsic biodegradation (aerobic and sequential anaerobic) within a three-dimensional flow field. SEAM3D also includes a module for simulating the dissolution of contaminants from a non-aqueous phase liquid (NAPL), such as gasoline or chlorinated solvents. With this capability, a mass-based approach is employed to simulate a contaminant source combined with attenuation of an aqueous-phase plume and to address time frames associated with MNA. This methodology is illustrated by considering the time of remediation in chlorinated ethene contaminated coastal-plain aquifers in Pensacola, Florida (trichloroethene, TCE) and in Kings Bay, Georgia (tetrachloroethene, PCE). At both sites, reductive dechlorination was a significant attenuation

  2. Sp receiver function imaging of a passive margin: Transect across Texas's Gulf Coastal Plain

    NASA Astrophysics Data System (ADS)

    Ainsworth, Ryan; Pulliam, Jay; Gurrola, Harold; Evanzia, Dominic

    2014-09-01

    The Gulf Coast of Texas has been the subject of intensive geological and geophysical investigation in pursuit of hydrocarbons but studies that penetrate beyond the upper crust are limited to a few refraction profiles and regional surface wave investigations. The passing of EarthScope's Transportable Array has facilitated regional investigations of the lithosphere but its 70-km station spacing does not allow many important tectonic features to be imaged. A broadband seismic transect across the Texas Gulf Coastal Plain was therefore performed in order to image deep structure beneath this passive margin and the transition to the neighboring craton. A 2D Sp receiver function common conversion point (CCP) stacked image produced for this transect reveals several discontinuities in the sub-crustal lithosphere. The region nearest the shoreline is underlain by an anomalous ∼18 km thick low velocity layer that produces a strong negative pulse in the Sp receiver functions. The drop in velocity is too large to be due to any reasonable change in Fe or Mg content but could be produced by partial melt or mantle hydration. It is unlikely that partial melt would still be found in a 160-180-year-old passive margin, such as the Gulf Coast, but hydration, possibly introduced by a through-going Balcones fault system, and resulting serpentinization could produce the observed anomaly. An event with negative polarity appears at a depth of ∼110 km, which we interpret to be the lithosphere-asthenosphere boundary (LAB). Thermal variations alone would not produce a sufficiently sharp discontinuity to be imaged by Sp converted phases. Recent shear-wave splitting studies revealed unusually large delay times in this region, along with fast polarization directions that differ from measurements on the Laurentian craton. Large delay times may imply significant flow, which could also produce frictional heating, due to shearing, and partial melt, which would steepen the velocity gradients. An

  3. Carbon, nitrogen, and phosphorus accumulation in floodplains of Atlantic Coastal Plain rivers, USA

    USGS Publications Warehouse

    Noe, G.B.; Hupp, C.R.

    2005-01-01

    Net nutrient accumulation rates were measured in riverine floodplains of the Atlantic Coastal Plain in Virginia, Maryland, and Delaware, USA. The floodplains were located in watersheds with different land use and included two sites on the Chickahominy River (urban), one site on the Mattaponi River (forested), and five sites on the Pocomoke River (agricultural). The Pocomoke River floodplains lie along reaches with natural hydrogeomorphology and on reaches with restricted flooding due to channelization and levees. A network of feldspar clay marker horizons was placed on the sediment surface of each floodplain site 3-6 years prior to sampling. Sediment cores were collected from the material deposited over the feldspar clay pads. This overlying sediment was separated from the clay layer and then dried, weighed, and analyzed for its total carbon (C), nitrogen (N), and phosphorus (P) content. Mean C accumulation rates ranged from 61 to 212 g??m-2??yr-1, N accumulation rates ranged from 3.5 to 13.4 g??m -2??yr-1, and P accumulation rates ranged from 0.2 to 4.1 g??m-2??yr-1 among the eight floodplains. Patterns of intersite variation in mineral sediment and P accumulation rates were similar to each other, as was variation in organic sediment and C and N accumulation rates. The greatest sediment and C, N, and P accumulation rates were observed on Chickahominy River floodplains downstream from the growing metropolitan area of Richmond, Virginia. Nutrient accumulation rates were lowest on Pocomoke River floodplains that have been hydraulically disconnected from the main channel by channelization and levees. Sediment P concentrations and P accumulation rates were much greater on the hydraulically connected floodplain immediately downstream of the limit of channelization and dense chicken agriculture of the upper Pocomoke River watershed. These findings indicate that (1) watershed land use has a large effect on sediment and nutrient retention in floodplains, and (2) limiting

  4. Sterol-inhibiting fungicide impacts on soil microbial ecology in Atlantic Coastal Plain soils

    NASA Astrophysics Data System (ADS)

    White, P. M.; Potter, T. L.; Strickland, T. C.

    2008-12-01

    Seventy-five percent of the peanuts (Arachus hypogaia) produced in the United States are grown in the Atlantic Coastal Plain region. Portions of this area, including Alabama and Georgia, exhibit a subtropical climate that promotes soil-borne plant fungal diseases. Most fields receive repeated fungicide applications during the growing season to suppress the disease causing organisms, such as Sclerotium rolfsii, Rhizoctonia solani, and Cylindrocladium parasiticum. Information regarding fungicide effects on the soil microbial community, with components principally responsible for transformation and fate of fungicides and other soil-applied pesticides, is limited. The objectives of the study were to assess soil microbial community response to (1) varying rates of the sterol-inhibiting fungicide tebuconazole (0, single application, season max, 2x season max), and (2) field rates of the sterol-inhibitors cyproconazole, prothioconazole, tebuconazole, and flutriafol, and thiol-competitor chlorothalonil. The sterol-inhibitors exhibited different half lives, as listed in the FOOTPRINT database, ranging from <1 day to >1300 d. Chlorothalonil was chosen because it is the most frequently applied fungicide to peanut. Shifts in the fungi, gram positive and gram negative bacteria, were monitored during the experiments using phospholipid fatty acid (PLFA) profiles. Ergosterol levels and pesticide decay rates were also monitored to evaluate the effectiveness of the fungicide and soil residence time, respectively. In the rate study, the highest rate of tebuconazole reduced the fungal biomarker 18:2ω6,9c to 2.6 nmol g-1 dry soil at 17 d, as compared to the control (4.1 nmol g-1 dry soil). However, levels of the fungal PLFA biomarker were similar regardless of rate at 0 and 32 d. The gram negative bacterial PLFA mole percent was greater at 17 d for the two highest rates of tebuconazole, but was similar at 0 and 32 d. Gram positive and fungal mole percents were not affected at any time

  5. Methods to assess natural and anthropogenic thaw lake drainage on the western Arctic coastal plain of northern Alaska

    NASA Astrophysics Data System (ADS)

    Hinkel, Kenneth M.; Jones, Benjamin M.; Eisner, Wendy R.; Cuomo, Chris J.; Beck, Richard A.; Frohn, Robert

    2007-06-01

    Thousands of lakes are found on the Arctic Coastal Plain of northern Alaska and northwestern Canada. Developed atop continuous permafrost, these thaw lakes and associated drained thaw lake basins are the dominant landscape elements and together cover 46% of the 34,570 km2 western Arctic Coastal Plain (WACP). Lakes drain by a variety of episodic processes, including coastal erosion, stream meandering, and headward erosion, bank overtopping, and lake coalescence. Comparison of Landsat multispectral scanner (MSS) imagery from the mid-1970s to Landsat 7 enhanced thematic mapper (ETM+) imagery from around 2000 shows that 50 lakes completely or partially drained over the approximately 25 year period, indicating landscape stability. The lake-specific drainage mechanism can be inferred in some cases and is partially dependant on geographic settings conducive to active erosion such as riparian and coastal zones. In many cases, however, the cause of drainage is unknown. The availability of high-resolution aerial photographs for the Barrow Peninsula extends the record back to circa 1950; mapping spatial time series illustrates the dynamic nature of lake expansion, coalescence, and drainage. Analysis of these historical images suggests that humans have intentionally or inadvertently triggered lake drainage near the village of Barrow. Efforts to understand landscape processes and identify events have been enhanced by interviewing Iñupiaq elders and others practicing traditional subsistence lifestyles. They can often identify the year and process by which individual lakes drained, thereby providing greater dating precision and accuracy in assessing the causal mechanism. Indigenous knowledge has provided insights into events, landforms, and processes not previously identified or considered.

  6. Tsunami Recurrences in the Ryukyu Arc-trench System: Geological Records in the Jinshan Coastal Plain of North Taiwan

    NASA Astrophysics Data System (ADS)

    Yu, N. T.; Yen, J. Y.; Lin, L. H.; Liu, J. H.

    2014-12-01

    Active continental margin like the Ryukyu arc-trench system poses high tsunami risk, which however remains poorly assessed due to the sparse historic records and geological studies. In order to better understand the tsunami risk in northern Taiwan of the southernmost Ryukyu active margin, borehole cores of the Jinshan Coastal Plain were investigated for the tsunami deposits of 1867 event and possibly its precursors. Based on facies characteristics, two decimeter-thick marine event sand beds are identified intercalated with the fluvial gravelly deposit that has been accumulated in a microtidal barred estuary over the past millennium. Distributed all over the coastal plain except the coastal sand spits, the fluvial deposit are predominantly sourced from the Pleistocene arc andesite, and thus commonly reddish in color due to the high iron content. The marine beds are rich in quartz sand and granule, whitish gray in color, and rounded to subangular in grain shape, indicating a sediment source from the coastal sand spits which receive longshore drift from the nearby rocky coasts dominated by the Oligocene and Miocene quartzose sandstone and mudstone. The facies succession of marine bed is characterized by erosion base, planar lamination, normal grading, soft-sediment deformation, and variations in magnetic susceptibility, Si, K, Ti, and Fe. The succession reflects the sedimentary processes from incoming wave erosion, rapid marine deposition, backflow reworking, and suspension fall-out. The marine beds are traceable landward based on the facies characteristics and C14 dating over a distance up to two kilometers before thinning out and grading into carbonaceous mud. According to the C14 dating, the two marine beds are linked to the 1867 tsunami and an earlier event in the late 17th century. Based on their ages and distributions, the two event beds further suggest two marine incursions of similar extant in an approximate recurrence interval of ~170 yr.

  7. Methods to assess natural and anthropogenic thaw lake drainage on the western Arctic coastal plain of northern Alaska

    USGS Publications Warehouse

    Hinkel, Kenneth M.; Jones, Benjamin M.; Eisner, Wendy R.; Cuomo, Chris J.; Beck, R.A.; Frohn, R.

    2007-01-01

    Thousands of lakes are found on the Arctic Coastal Plain of northern Alaska and northwestern Canada. Developed atop continuous permafrost, these thaw lakes and associated drained thaw lake basins are the dominant landscape elements and together cover 46% of the 34,570 km2western Arctic Coastal Plain (WACP). Lakes drain by a variety of episodic processes, including coastal erosion, stream meandering, and headward erosion, bank overtopping, and lake coalescence. Comparison of Landsat multispectral scanner (MSS) imagery from the mid-1970s to Landsat 7 enhanced thematic mapper (ETM+) imagery from around 2000 shows that 50 lakes completely or partially drained over the approximately 25 year period, indicating landscape stability. The lake-specific drainage mechanism can be inferred in some cases and is partially dependant on geographic settings conducive to active erosion such as riparian and coastal zones. In many cases, however, the cause of drainage is unknown. The availability of high-resolution aerial photographs for the Barrow Peninsula extends the record back to circa 1950; mapping spatial time series illustrates the dynamic nature of lake expansion, coalescence, and drainage. Analysis of these historical images suggests that humans have intentionally or inadvertently triggered lake drainage near the village of Barrow. Efforts to understand landscape processes and identify events have been enhanced by interviewing Iñupiaq elders and others practicing traditional subsistence lifestyles. They can often identify the year and process by which individual lakes drained, thereby providing greater dating precision and accuracy in assessing the causal mechanism. Indigenous knowledge has provided insights into events, landforms, and processes not previously identified or considered.

  8. Toward Understanding Mechanisms Controlling Urea Delivery in a Coastal Plain Watershed

    NASA Astrophysics Data System (ADS)

    Tzilkowski, S. S.; Buda, A. R.; Boyer, E. W.; Bryant, R. B.; May, E. B.

    2012-12-01

    Improved understanding of nutrient mobilization and delivery to surface waters is critical to protecting water quality in agricultural watersheds. Urea, a form of organic nitrogen, is a common nutrient found in fertilizers, manures, and human waste, and is gaining recognition as an important driver of coastal eutrophication, particularly through the development of harmful algal blooms. While several studies have documented elevated urea concentrations in tributaries draining to the Chesapeake Bay, little is known about the potential sources and flow pathways responsible for urea delivery from the landscape to surface waters, as well as how these sources and pathways might vary with changing seasons, antecedent conditions, and storm types. In this study, we investigated hydrologic controls on urea delivery in the Manokin River watershed through the analysis of urea concentration dynamics and hysteresis patterns during seven storm events that occurred in 2010 and 2011. The Manokin River is a Coastal Plain watershed (11.1 km2) on the Delmarva Peninsula that drains directly to the Chesapeake Bay and is characterized by extensive rural development coupled with intensive agriculture, particularly poultry production. Sampling was conducted through monthly grab sampling at baseflow conditions and by time-weighted, automated (Sigma) samplers during stormflow events. Monitored storms were chosen to represent a spectrum of antecedent conditions based on precipitation and groundwater levels in the area. Flushing from the landscape during events was found to be the predominant urea delivery mechanism, as urea concentrations increased 3-9 times above baseflow concentrations during storms. The timing and number of flushes, as well as the degree of increased concentrations were dependent on antecedent conditions and the characteristics of the storm event. For instance, during an intense (13.7 mm hr-1), short-duration (4 hrs) storm in August of 2010 when antecedent conditions were

  9. Geophysical detection of on-site wastewater plumes in the North Carolina Coastal Plain, USA

    NASA Astrophysics Data System (ADS)

    Smith, Matthew

    Nonpoint source pollution (NPS) continues to be the leading cause of water quality degradation in the United States. On-site wastewater systems (OWS) contribute to NPS; however, due to the range of system designs and complexity of the subsurface, OWS contributions to groundwater pollution are not well understood. As the population of coastal North Carolina continues to increase, better methods to locate and characterize wastewater impacted groundwater are needed. Previous studies have demonstrated the ability of non-intrusive geophysical methods to provide high resolution information on various contaminants in different geologic settings. The goals of this study were to evaluate the utility of ground penetrating radar (GPR) and capacitively coupled resistivity (CCR) for detecting OWS components, delineating associated wastewater plumes, and monitoring temporal variations in groundwater quality. Cross-sectional and three dimensional (3D) geophysical surveys were conducted periodically over a one year period (February 2011--January 2012) at two schools utilizing OWS in the lower Neuse River Basin (NRB) in the North Carolina Coastal Plain (NCCP). Cores were collected at both study sites; as well as monthly groundwater depth, temperature, and specific conductivity measurements to better constrain the geophysical interpretations. Additionally, dissolved inorganic nitrogen (DIN) and Cl concentrations were monitored bi-monthly to assess nutrient transport at the sites. The 3D GPR surveys effectively located the wastewater drainage trenches at both sites, in close agreement with locations described in as-built OWS blueprints. Regression analysis of resistivity versus groundwater specific conductivity revealed an inverse relationship, suggesting resistivity ≤ 250 ohm.m was indicative of wastewater impacted groundwater at both sites. The 3D resistivity models identified regions of low resistivity beneath the drainfields relative to background values. Regression analysis of

  10. Numerical modelling and hydrochemical characterisation of a fresh-water lens in the Belgian coastal plain

    NASA Astrophysics Data System (ADS)

    Vandenbohede, A.; Lebbe, L.

    2002-05-01

    The distribution of fresh and salt water in coastal aquifers is influenced by many processes. The influence of aquifer heterogeneity and human interference such as land reclamation is illustrated in the Belgian coastal plain where, around A.D. 1200, the reclamation of a tidally influenced environment was completed. The aquifer, which was filled with salt water, was thereafter freshened. The areal distribution of peat, clay, silt and sand influences the general flow and distribution of fresh and salt water along with the drainage pattern and results in the development of fresh-water lenses. The water quality in and around the fresh-water lenses below an inverted tidal channel ridge is surveyed. The hydrochemical evolution of the fresh water lens is reconstructed, pointing to cation exchange, solution of calcite and the oxidation of organic material as the major chemical reactions. The formation and evolution of the fresh water lens is modelled using a two-dimensional density-dependent solute transport model and the sensitivity of drainage and conductivities are studied. Drainage level mainly influences the depth of the fresh-water lens, whereas the time of formation is mainly influenced by conductivity. Résumé. La répartition de l'eau douce et de l'eau salée dans les aquifères littoraux est influencée par de nombreux mécanismes. L'influence de l'hétérogénéité de l'aquifère et des interférences anthropiques telles que la mise en valeur des terres est illustrée par la plaine côtière belge où, depuis l'an 1200, on a mis en valeur un environnement soumis aux marées. L'aquifère, qui contenait de l'eau salée, contient maintenant de l'eau douce. La distribution spatiale de tourbe, d'argile, de silt et de sable joue un rôle dans l'écoulement général et dans la répartition de l'eau douce et de l'eau salée le long du réseau de drainage et produit des lentilles d'eau douce. La qualité de l'eau dans et autour des lentilles d'eau douce sous une lev

  11. Characterization of geomorphic units in the alluvial valleys and channels of Gulf Coastal Plain rivers in Texas, with examples from the Brazos, Sabine, and Trinity Rivers, 2010

    USGS Publications Warehouse

    Coffman, David K.; Malstaff, Greg; Heitmuller, Franklin T.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the Texas Water Development Board, described and characterized examples of geomorphic units within the channels and alluvial valleys of Texas Gulf Coastal Plain rivers using a geomorphic unit classification scale that differentiates geomorphic units on the basis of their location either outside or inside the river channel. The geomorphic properties of a river system determine the distribution and type of potential habitat both within and adjacent to the channel. This report characterizes the geomorphic units contained in the river channels and alluvial valleys of Texas Gulf Coastal Plain rivers in the context of the River Styles framework. This report is intended to help Texas Instream Flow Program practitioners, river managers, ecologists and biologists, and others interested in the geomorphology and the physical processes of the rivers of the Texas Gulf Coastal Plain (1) gain insights into how geomorphic units develop and adjust spatially and temporally, and (2) be able to recognize common geomorphic units from the examples cataloged in this report. Recent aerial imagery (high-resolution digital orthoimagery) collected in 2008 and 2009 were inspected by using geographic information system software to identify representative examples of the types of geomorphic units that occurred in the study area. Geomorphic units outside the channels of Texas Gulf Coastal Plain rivers are called \\"valley geomorphic units\\" in this report. Valley geomorphic units for the Texas Gulf Coastal Plain rivers described in this report are terraces, flood plains, crevasses and crevasse splays, flood-plain depressions, tie channels, tributaries, paleochannels, anabranches, distributaries, natural levees, neck cutoffs, oxbow lakes, and constructed channels. Channel geomorphic units occur in the river channel and are subject to frequent stresses associated with flowing water and sediment transport; they adjust (change) relatively quickly in

  12. Mammal Diversity and Infection Prevalence in the Maintenance of Enzootic Borrelia burgdorferi along the Western Coastal Plains of Maryland

    PubMed Central

    ANDERSON, JENNIFER M.; SWANSON, KATHERINE I.; SCHWARTZ, TIMOTHY R.; GLASS, GREGORY E.; NORRIS, DOUGLAS E.

    2014-01-01

    The primary vector of Borrelia burgdorferi in North America, Ixodes scapularis, feeds on various mammalian, avian, and reptilian hosts. Several small mammal hosts; Peromyscus leucopus, Tamias striatus, Microtus pennsylvanicus, and Blarina spp. can serve as reservoirs in an enzootic cycle of Lyme disease. The primary reservoir in the northeast United States is the white-footed mouse, P. leucopus. The infection prevalence of this reservoir as well as the roles of potential secondary reservoirs has not been established in southern Maryland, a region of low to moderate Borrelia infection in humans. Intensive trapping at 96 locations throughout the western Coastal Plains of Maryland was conducted and we found that 31.6% of P. leucopus were infected with B. burgdorferi. Sequence and phylogenetic analysis revealed that only B. burgdorferi sensu stricto circulated in southern Maryland. Feral house mice and voles also were infected and may serve as secondary hosts. Peromyscus gender, age and month of capture were significantly associated with infection status. Larval I. scapularis were the dominant ectoparasite collected from captured rodents even though host seeking A. americanum and D. variabilis were collected in greater numbers across the sampling region. Our findings illustrate that the enzootic cycle of LD is maintained in the western Coastal Plains region of southern Maryland between I. scapularis and P. leucopus as the dominant reservoir. PMID:17187577

  13. Biostratigraphic correlation of Pleistocene marine deposits and sea levels, Atlantic coastal plain of the southeastern United States

    USGS Publications Warehouse

    Cronin, T. M.

    1980-01-01

    Marine ostracodes from 50 localities were studied to determine the age and elevation of Pleistocene sea levels in the Atlantic coastal plain from Maryland to northern Florida. Using ostracode taxon and concurrent ranges, published planktic biostratigraphic, paleomagnetic, and radiometric data, ostracode assemblage zones representing early (1.8-1.0 my), middle (0.7-0.4 my), and late (0.3-0.01 my) Pleistocene deposition were recognized and used as a basis for correlation. Ostracode biofacies signifying lagoonal, oyster bank, estuarine, open sound, and inner sublittoral environments provided estimated ranges of paleodepths for each locality. From these data the following minimum and maximum Pleistocene sea-level estimates were determined for the southeastern coastal plain: late Pleistocene, 2-10 m from Maryland to northern Florida; middle Pleistocene, 6-15 m in northern South Carolina; early Pleistocene, 4-22 m in central North Carolina, 13-35 m in southern North Carolina, and 6-27 m in South Carolina. Climatically induced glacio-eustatic sea-level fluctuations adequately account for the late Pleistocene sea-level data, but other factors, possibly differential crustal uplift, may have complicated the early Pleistocene record. ?? 1980.

  14. High-resolution hydro- and geo-stratigraphy at Atlantic Coastal Plain drillhole CR-622 (Strat 8)

    USGS Publications Warehouse

    Wrege, B.M.; Isely, J.J.

    2009-01-01

    We interpret borehole geophysical logs in conjunction with lithology developed from continuous core to produce high-resolution hydro- and geo-stratigraphic profiles for the drillhole CR-622 (Strat 8) in the Atlantic Coastal Plain of North Carolina. The resulting hydrologic and stratigraphic columns show a generalized relation between hydrologic and geologic units. Fresh-water aquifers encountered are the surficial, Yorktown, Pungo River and Castle Hayne. Geologic units present are of the middle and upper Tertiary and Quaternary periods, these are the Castle Hayne (Eocene), Pungo River (Miocene), Yorktown (Pliocene), James City and Flanner Beach (Pleistocene), and the topsoil (Holocene). The River Bend Formation (Oligocene) is missing as a distinct unit between the Pungo River Formation and the Castle Hayne Formation. The confining unit underlying the Yorktown Aquifer corresponds to the Yorktown Geologic Unit. The remaining hydrologic units and geologic units are hydrologically transitional and non-coincident. The lower Pungo River Formation serves as the confining unit for the Castle Hayne Aquifer, rather than the River Bend Aquifer, and separates the Pungo River Aquifer from the upper Castle Hayne Aquifer. All geologic formations were bound by unconformities. All aquifers were confined by the anticipated hydrologic units. We conclude that CR-622 (Strat 8) represents a normal sequence in the Atlantic Coastal Plain.

  15. Seismic hazard in the South Carolina coastal plain: 2002 update of the USGS national seismic hazard maps

    USGS Publications Warehouse

    Cramer, C.H.; Mays, T.W.; ,

    2005-01-01

    The damaging 1886 moment magnitude ???7 Charleston, South Carolina earthquake is indicative of the moderately likely earthquake activity along this portion of the Atlantic Coast. A recurrence of such an earthquake today would have serious consequences for the nation. The national seismic hazard maps produced by the U.S. Geological Survey (USGS) provide a picture of the levels of seismic hazard across the nation based on the best and most current scientific information. The USGS national maps were updated in 2002 and will become part of the International Codes in 2006. In the past decade, improvements have occurred in the scientific understanding of the nature and character of earthquake activity and expected ground motions in the central and eastern U.S. The paper summarizes the new knowledge of expected earthquake locations, magnitudes, recurrence, and ground-motion decay with distance. New estimates of peak ground acceleration and 0.2 s and 1.0 s spectral acceleration are compared with those displayed in the 1996 national maps. The 2002 maps show increased seismic hazard in much of the coastal plain of South Carolina, but a decrease in long period (1 s and greater) hazard by up to 20% at distances of over 50 km from the Charleston earthquake zone. Although the national maps do not account for the effects of local or regional sediments, deep coastal-plain sediments can significally alter expected ground shaking, particularly at long period motions where it can be 100% higher than the national maps.

  16. Landsat digital data as tool for mining exploration and geologic mapping in coastal plain of Malaysian Peninsula

    SciTech Connect

    Prelat, A.E.

    1986-07-01

    Landsat Multispectral Scanner (MSS) data were used for systematic mapping of the coastal plain of the Malaysian Peninsula. The study was conducted to evaluate the use of Landsat digital data to assist the geologist in the exploration and mapping of the coastal plain of the Malaysian peninsula. The brightness of the four Landsat MSS channels and six ratios were recorded for each pixel, and were subsequently used as input to the supervised classification technique. Several lithologic units were selected to define training groups, and the remaining study area was classified into the preselected categories. The results indicated that using Landsat digital data combined with geologic and topographic information can improve the interpretation and quality of the geologic maps. The Landsat information was an effective tool to delineate the structural features and recognize different geologic patterns that can be defined as exploration targets. The most useful Landsat parameters to study the geology in the area were channels 5 and 7 and their ratio 7/5. Vegetation areas were enhanced by the ratio 6/4. Further field work in the area will confirm the results of the present study.

  17. Assessment of groundwater availability in the Northern Atlantic Coastal Plain aquifer system From Long Island, New York, to North Carolina

    USGS Publications Warehouse

    Masterson, John P.; Pope, Jason P.; Fienen, Michael N.; Monti, Jr., Jack; Nardi, Mark R.; Finkelstein, Jason S.

    2016-08-31

    Executive SummaryThe U.S. Geological Survey began a multiyear regional assessment of groundwater availability in the Northern Atlantic Coastal Plain (NACP) aquifer system in 2010 as part of its ongoing regional assessments of groundwater availability of the principal aquifers of the Nation. The goals of this national assessment are to document effects of human activities on water levels and groundwater storage, explore climate variability effects on the regional water budget, and provide consistent and integrated information that is useful to those who use and manage the groundwater resource. As part of this nationwide assessment, the USGS evaluated available groundwater resources within the NACP aquifer system from Long Island, New York, to northeastern North Carolina.The northern Atlantic Coastal Plain physiographic province depends heavily on groundwater to meet agricultural, industrial, and municipal needs. The groundwater assessment of the NACP aquifer system included an evaluation of how water use has changed over time; this evaluation primarily used groundwater budgets and development of a numerical modeling tool to assess system responses to stresses from future human uses and climate trends.This assessment focused on multiple spatial and temporal scales to examine changes in groundwater pumping, storage, and water levels. The regional scale provides a broad view of the sources and demands on the system with time. The sub-regional scale provides an evaluation of the differing response of the aquifer system across geographic areas allowing for closer examination of the interaction between different aquifers and confining units and the changes in these interactions under pumping and recharge conditions in 2013 and hydrologic stresses as much as 45 years in the future. By focusing on multiple scales, water-resource managers may utilize this study to understand system response to changes as they affect the system as a whole.The NACP aquifer system extends from

  18. Private Domestic-Well Characteristics and the Distribution of Domestic Withdrawals among Aquifers in the Virginia Coastal Plain

    USGS Publications Warehouse

    Pope, Jason P.; McFarland, E. Randolph; Banks, R. Brent

    2008-01-01

    A comprehensive analysis of private domestic wells and self-supplied domestic ground-water withdrawals in the Coastal Plain Physiographic Province of Virginia indicates that the magnitudes of these withdrawals and their effects on local and regional ground-water flow are larger and more important than previous reports have stated. Self-supplied ground-water withdrawals for domestic use in the Virginia Coastal Plain are estimated to be approximately 40 million gallons per day, or about 28 percent of all ground-water withdrawals in the area. Contrary to widely held assumptions, only 22 percent of domestic wells in the Virginia Coastal Plain are completed in the shallow, unconfined surficial aquifer to which the water is returned directly by home septic systems. Fifty-three percent of the wells are completed in six deeper confined aquifers, and the remaining 25 percent are completed in the Potomac aquifer and confining zone, the deepest units in the confined system. Assuming an equal rate of withdrawal per well, 78 percent of domestic ground-water withdrawal, or about 30 million gallons per day, is removed from the regional confined ground-water system. Domestic ground-water withdrawal from an estimated 200,000 private wells supplies more than 15 percent of the population of the area and provides almost the entire source of water in some rural counties. The geographic distribution of these withdrawals is dependent on the self-supplied population and is highly variable. Domestic-well characteristics vary spatially as well, primarily because of geographic differences in depths to particular aquifers, but also because of well-drilling practices that are influenced by geographic, regulatory, and socioeconomic factors. Domestic ground-water withdrawals in the Virginia Coastal Plain were characterized as part of a larger study to analyze the regional ground-water flow system. Characterizing the withdrawals required differentiation of the withdrawals among the aquifers in

  19. Salinization and freshening of coastal aquifers with land reclamation, in the SE Po plain (Italy), the Netherlands and Belgium

    NASA Astrophysics Data System (ADS)

    Mollema, P. N.; Antonellini, M. A.; Dinelli, E.; Greggio, N.; Stuyfzand, P. J.; Vandenbohede, A.

    2012-12-01

    The coastal aquifers of the Southern Po plain in Italy, the Netherlands and Belgium have a similar setting. All three areas are characterized by one or more dune belts parallel to the coast and low lying, mechanically drained polders and formed during the Holocene resulting in a comparable geology. Nonetheless, the salinization and freshening trends of the groundwater are different resulting in a different hydrochemical signature. This is due to differences in climate, recharge areas and human interference. Impoldering started in the 1960's in Italy. The coastal aquifer of the southern Po plain currently contains mostly brackish to saline NaCl type groundwater. Calcium rich water is found only in the rivers, in the irrigation channels and in a few wells. Cation, anion, stable isotopes and the analysis of tracers such as SO4/Cl- and 18O/Cl- show that most ground water samples are a mix between fresh water and Adriatic Sea water. Six hydrosomes were recognized: Holocene transgression, Po River, Apennine River, new coastal dune, paleodunes, and current lagoon water. As the sea regressed 30 km eastwards in the past 6000 yrs, fresh water infiltrated into the beach sand deposits but because of the small recharge areas and small amount of recharge, there was never enough fresh water to expel the Holocene seawater. Land reclamation dried the original marshes and lagoons. The location of pumping stations far from the coast caused the formation of hydraulic gradients enhancing saltwater intrusion inland. Land reclamation and impoldering started very early (10th century) in the Belgian and Dutch case and was completed in the 12th century in Belgium and in the Netherlands not until 1967. The aquifer system in the Netherlands is thicker than in Belgium. Complex Holocene evolution with mudflats alternating with peat bogs resulted in a current day complex fresh-saltwater distribution in the Belgian and Dutch coastal plain. Young fresh water lenses occur above older brackish water

  20. Do Tsunami Deposits Thin Landward? Observations from the 11 March 2011 Tohoku-oki Tsunami on the Sendai Coastal Plain

    NASA Astrophysics Data System (ADS)

    Richmond, B. M.; Jaffe, B. E.; Gelfenbaum, G. R.; Szczucinski, W.; Goto, K.; Sugawara, D.; Witter, R. C.; Tappin, D. R.; Shigehiro, F.; Nishimura, Y.; Chague-Goff, C.; Goff, J. R.

    2012-12-01

    Case studies of recent tsunami impacts have proven to be extremely useful in understanding the geologic processes involved during inundation and return flow, and refining the criteria used to identify paleotsunami deposits in the geologic record. Here, we report on the spatial distribution of deposit thickness resulting from the March, 2011 Tohoku-oki tsunami along a nearly 4.5 km shore-normal sampling transect on the coastal plain near Sendai, Japan. The study area consisted of a broad, low-relief prograding coastal plain which comprised a broad sand beach backed by low (~3 m) sand dunes and forest; a wetland and a shore-parallel engineered drainage canal several meters deep and ~40 m wide; agricultural rice fields marked by low-lying rectangular dyke systems with occasional buildings, canals, and roads; and an elevated highway embankment which generally marked the landward extent of inundation except where gaps in the structure allowed flow to penetrate further inland. Field observations in May 2011 documented a tsunami deposit that generally thinned landward from an average maximum ~30 cm thick sand deposit in the coastal forest to a thin mud drape several mm thick near the inundation limit. Although there was an overall thinning of the deposit, this trend was often interrupted by localized features that led to variability in deposit thickness (from 0 to 20+ cm) over short distances (<10 m) along transect and adjacent to the main transect. The variability in both the along- and transverse flow directions is related to micro-topography, sediment source availability, and gradients in flow speed and duration. Although there is an overall landward thinning of the deposit, localized thinning and thickening occurred in numerous locations along our transect. This information is critical for accurately identifying paleotsunami deposits and for improving tsunami hazard assessment from the geologic record.

  1. Corrosiveness of ground water in the Kirkwood-Cohansey aquifer system of the New Jersey Coastal Plain

    USGS Publications Warehouse

    Barringer, J.L.; Kish, G.R.; Velnich, A.J.

    1993-01-01

    Ground water from the unconfined part of the Kirkwood-Cohansey aquifer system in the New Jersey Coastal Plain typically is corrosive-- that is, it is acidic, soft, and has low concentrations of alkalinity. Corrosive ground water has the potential to leach trace elements and asbestos fibers from plumbing materials used in potable- water systems, thereby causing potentially harmful concentrations of these substances in drinking water. Corrosion indices were calculated from water-quality data for 370 wells in the unconfined Kirkwood-Cohansey aquifer system. Values of the Langelier Saturation Index are predominantly negative, indicating that the water is undersaturated with respect to calcium carbonate, and, therefore, is potentially corrosive. Values of the Aggressive Index, a similar estimator of the corrosiveness of water, range from 3.9 (highly corrosive) to 11.9 (moderately corrosive). The median Aggressive Index value calculated for the 370 wells is 6.0, a value that indicates that the water is highly corrosive. Moderately corrosive ground water is found in some coastal areas. Isolated instances of moderately corrosive water are found in northern Ocean County, and in Burlington, Camden, and Salem Counties. In the vicinity of Ocean County corrosion-index values change little with depth, but in Atlantic, Burlington, and Salem Counties the corrosiveness of ground water generally appears to decrease with depth. Analyses of standing tap water from newly constructed homes in the Coastal Plain show concentrations of lead and other trace elements are significantly higher than those in ambient ground water. The elevated trace-element concentrations are attributed to the corrosion of plumbing materials by ground water. Results of the tap-water analyses substantiate the corrosiveness of Kirkwood-Cohansey ground water, as estimated by corrosion-index values.

  2. Surface faults in the gulf coastal plain between Victoria and Beaumont, Texas

    USGS Publications Warehouse

    Verbeek, E.R.

    1979-01-01

    Displacement of the land surface by faulting is widespread in the Houston-Galveston region, an area which has undergone moderate to severe land subsidence associated with fluid withdrawal (principally water, and to a lesser extent, oil and gas). A causative link between subsidence and fluid extraction has been convincingly reported in the published literature. However, the degree to which fluid withdrawal affects fault movement in the Texas Gulf Coast, and the mechanism(s) by which this occurs are as yet unclear. Faults that offset the ground surface are not confined to the large (>6000-km2) subsidence "bowl" centered on Houston, but rather are common and characteristic features of Gulf Coast geology. Current observations and conclusions concerning surface faults mapped in a 35,000-km2 area between Victoria and Beaumont, Texas (which area includes the Houston subsidence bowl) may be summarized as follows: 1. (1) Hundreds of faults cutting the Pleistocene and Holocene sediments exposed in the coastal plain have been mapped. Many faults lie well outside the Houston-Galveston region; of these, more than 10% are active, as shown by such features as displaced, fractured, and patched road surfaces, structural failure of buildings astride faults, and deformed railroad tracks. 2. (2) Complex patterns of surface faults are common above salt domes. Both radial patterns (for example, in High Island, Blue Ridge, Clam Lake, and Clinton domes) and crestal grabens (for example, in the South Houston and Friendswood-Webster domes) have been recognized. Elongate grabens connecting several known and suspected salt domes, such as the fault zone connecting Mykawa, Friendswood-Webster, and Clear Lake domes, suggest fault development above rising salt ridges. 3. (3) Surface faults associated with salt domes tend to be short (10 km), occur singly or in simple grabens, have gently sinuous traces, and tend to lie roughly parallel to the ENE-NE "coastwise" trend common to regional growth

  3. Groundwater-quality data and regional trends in the Virginia Coastal Plain, 1906-2007

    USGS Publications Warehouse

    McFarland, E. Randolph

    2010-01-01

    A newly developed regional perspective of the hydrogeology of the Virginia Coastal Plain incorporates updated information on groundwater quality in the area. Local-scale groundwater-quality information is provided by a comprehensive dataset compiled from multiple Federal and State agency databases. Groundwater-sample chemical-constituent values and related data are presented in tables, summaries, location maps, and discussions of data quality and limitations. Spatial trends in groundwater quality and related processes at the regional scale are determined from interpretive analyses of the sample data. Major ions that dominate the chemical composition of groundwater in the deep Piney Point, Aquia, and Potomac aquifers evolve eastward and with depth from (1) 'hard' water, dominated by calcium and magnesium cations and bicarbonate and carbonate anions, to (2) 'soft' water, dominated by sodium and potassium cations and bicarbonate and carbonate anions, and lastly to (3) 'salty' water, dominated by sodium and potassium cations and chloride anions. Chemical weathering of subsurface sediments is followed by ion exchange by clay and glauconite, and subsequently by mixing with seawater along the saltwater-transition zone. The chemical composition of groundwater in the shallower surficial and Yorktown-Eastover aquifers, and in basement bedrock along the Fall Zone, is more variable as a result of short flow paths between closely located recharge and discharge areas and possibly some solutes originating from human sources. The saltwater-transition zone is generally broad and landward-dipping, based on groundwater chloride concentrations that increase eastward and with depth. The configuration is convoluted across the Chesapeake Bay impact crater, however, where it is warped and mounded along zones having vertically inverted chloride concentrations that decrease with depth. Fresh groundwater has flushed seawater from subsurface sediments preferentially around the impact crater

  4. Soil Fertility and Radicular System Depth of Sand Coastal Plain Forest

    NASA Astrophysics Data System (ADS)

    Casagrande, José Carlos; Akemi Sato, Claudia; Reis-Duarte, Rose Mary; Soares, Marcio Roberto; Sérgio Galvão Bueno, Mário

    2010-05-01

    The sand coastal plain vegetation (Restinga Forest) is a type of ecosystem associated with the Atlantic Forest constituted of mosaics, which occur in areas of great ecological diversity. This vegetation is currently assigned as edaphic communities. In this study we present data on soil fertility in different vegetation physiognomies to discuss on abiotic factors related to Restinga Forest stability and recovery potential. This work was carried out in several points of Restinga Forest in the litoral coast of the state of São Paulo, namely: State Park of the Serra do Mar, Picinguaba, in the city of Ubatuba (23°20' e 23°22' S / 44°48' e 44°52' W); State Park of Anchieta Island, in the city of Ubatuba (45°02' e 45°05' W / 23°31' e 23° 45' S); Restinga Forest in the residential joint ownership Riviera of São Lourenço, in the city of Bertioga (46°08' W e 23°51' S); Ecological Station Juréia-Itatins, Ecological Station of Chauas , in the city of Iguape (24°45' S e 47°33' W) and State Park of Cardoso Island, Pereirinha Restinga Forest, in the city of Cananéia (25°03'05" e 25°18'18" S / 47°53'48" e 48° 05'42" W), Brazil. Sampling was carried out as follows in every area above mentioned. One sample was made of 15 subsamples of each area collected in each depth (one in 0 - 5, 5 - 10, 10 - 15, 15 - 20, and another in 0 - 20, 20 - 40, 40 and 60 cm). Soil characteristics analyzed were pH, P, Na, K, Ca, Mg, S, H + Al, Al, B, Cu, Fe, Mn, Zn contents and base saturation, cation exchange capacity and aluminum saturation. All areas investigated showed very low contents of phosphorous, calcium and magnesium. The base saturation, less than 10, was low due to low amounts of Na, K, Ca and Mg, indicating low nutritional reserve into the soil. The nutritional reserve is present primarily in a depth of 15 cm, although mainly in the vegetable biomass. The level of calcium and magnesium were mainly low in the subsurface soil layer, associate with high concentration of

  5. Planning report for the Gulf Coast Regional Aquifer-System Analysis in the Gulf of Mexico coastal plain, United States

    USGS Publications Warehouse

    Grubb, Hayes F.

    1984-01-01

    Large quantities of water for municipal, industrial and agriculture use are supplied from the aquifers in Tertiary and younger sediments over an area of about 225,000 square miles in the Coastal Plain of Alabama, Arkansas, Florida, Illinois, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, and Texas. Three regional aquifer systems, the Mississippi Embayment aquifer system, the Coastal Lowlands aquifer system, and the Texas Coastal Uplands aquifer system have been developed to varying degrees throughout the area. A variety of problems has resulted from development such as movement of the saline-freshwater interface into parts of aquifers that were previously fresh, lowering of the potentiometric surface with resulting increases in pumping lift, and land-surface subsidence due to the compaction of clays within the aquifer. Increased demand for ground water is anticipated to meet the needs of urban growth, expanded energy development, and growth of irrigated agriculture. The U. S. Geological Survey initiated an eightyear study in 1981 to define the geohydrologic framework, describe the chemistry of the ground water, and to analyze the regional ground-water flow patterns. The objectives, plan, and organization of the study are described in this report and the major tasks to be undertaken are outlined.

  6. Environmental setting and factors that affect water quality in the Georgia-Florida Coastal Plain study unit

    USGS Publications Warehouse

    Berndt, M.P.; Oaksford, E.T.; Darst, M.R.; Marella, R.L.

    1996-01-01

    The Georgia-Florida Coastal Plain study unit covers an area of nearly 62,000 square miles in the southeastern United States, mostly in the Coastal Plain physiographic province. Land resource provinces have been designated based on generalized soil classifications. Land resource provinces in the study area include: the Coastal Flatwoods, the Southern Coastal Plain, the Central Florida Ridge, the Sand Hills, and the Southern Piedmont. The study area includes all or parts of seven hydrologic subregions: the Ogeechee-Savannah, the Altamaha- St.Marys, the Suwannee, the Ochlockonee, the St. Johns, the Peace-Tampa Bay, and the Southern Florida. The primary source of water for public supply in the study area is ground water from the Upper Floridan aquifer. In 1990, more than 90 percent of the 2,888 million gallons per day of ground water used came from this aquifer. The population of the study area was 9.3 million in 1990. The cities of Jacksonville, Orlando, St. Petersburg, Tallahassee, and Tampa, Florida, and parts of Atlanta and Savannah, Georgia, are located in the study area. Forest and agricultural areas are the most common land uses in the study area, accounting for 48 percent and 25 percent of the study area, respectively. Climatic conditions range from temperate in Atlanta, Georgia, where mean annual temperature is about 61.3 degrees Fahrenheit, to subtropical in Tampa, Florida, where mean annual temperature is about 72.4 degrees Fahrenheit. Long-term average precipitation (1961-90) ranges from 43.9 inches per year in Tampa, Florida, and 44.6 in Macon, Georgia, to 65.7 inches per year in Tallahassee, Florida. Floods in the study area result from frontal systems, hurricanes, tropical storms, or severe thunderstorms. Droughts are not common in the study area,especially in the Florida part of the study area due to extensive maritime exposure. The primary physical and cultural characteristics in the study area include physiography, soils and land resource provinces

  7. Application of remote sensing data to land use and land cover assessment in the Tubarao River coastal plain, Santa Catarina, Brazil

    NASA Technical Reports Server (NTRS)

    1982-01-01

    By means of aerial photography and MSS-LANDSAT data a land use/land cover classification was applied to the Tubarao River coastal plain. The following classes were identified: coal related areas, permanently flooded wetlands, periodically flooded wetlands, agricultural lands, bare soils, water bodies, urban areas, forestlands.

  8. Evaluation of amendments to decrease high strength in southeastern USA Coastal Plain soils using fuzzy multi-attributive comparison of alternatives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Productivity of many southeastern USA Coastal Plain soils is reduced by cemented subsurface layers that restrict root growth. Though tillage is the usual way to reduce cementation, if soil amendments can develop aggregation, they offer a more permanent solution. To improve soil physical properties a...

  9. Grenville age of basement rocks in Cape May NJ well: New evidence for Laurentian crust in U.S. Atlantic Coastal Plain basement Chesapeake terrane

    USGS Publications Warehouse

    Sheridan, R.E.; Maguire, T.J.; Feigenson, M.D.; Patino, L.C.; Volkert, R.A.

    1999-01-01

    The Chesapeake terrane of the U.S. mid-Atlantic Coastal Plain basement is bounded on the northwest by the Salisbury positive gravity and magnetic anomaly and extends to the southeast as far as the Atlantic coast. It underlies the Coastal Plain of Virginia, Maryland, Delaware and southern New Jersey. Rubidium/Strontium dating of the Chesapeake terrane basement yields an age of 1.025 ?? 0.036 Ga. This age is typical of Grenville province rocks of the Middle to Late Proterozoic Laurentian continent. The basement lithologies are similar to some exposed Grenville-age rocks of the Appalachians. The TiO2 and Zr/P2O5 composition of the metagabbro from the Chesapeake terrane basement is overlapped by those of the Proterozoic mafic dikes in the New Jersey Highlands. These new findings support the interpretation that Laurentian basement extends southeast as far as the continental shelf in the U.S. mid-Atlantic region. The subcrop of Laurentian crust under the mid-Atlantic Coastal Plain implies unroofing by erosion of the younger Carolina (Avalon) supracrustal terrane. Dextral-transpression fault duplexes may have caused excessive uplift in the Salisbury Embayment area during the Alleghanian orogeny. This extra uplift in the Salisbury area may have caused the subsequent greater subsidence of the Coastal Plain basement in the embayment.

  10. Effect of conservation practices on soil carbon and nitrogen accretion and crop yield in a corn production system in the southeastern coastal plain, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We implemented conservation farming practices (winter cover cropping plus strip tillage) for a non-irrigated corn production system in the southern coastal plain of Georgia, USA that had been previously been managed under a plow and harrow tillage regime. Total soil carbon and nitrogen were measure...

  11. PREDICTING THE OCCURRENCE OF NUTRIENTS AND PESTICIDES DURING BASE FLOW IN STREAMS: STATUS OF MID-ATLANTIC COASTAL PLAIN AND MIDWEST CORN BELT STUDIES

    EPA Science Inventory

    Random surveys of 174 headwater streams of the Mid-Atlantic Coastal Plain (MACP) and 110 third-order streams in the Midwest Corn Belt (MCB) were conducted in 2000 and 2004, respectively in two cooperative research studies by the U.S. Environmental Protection Agency and U.S. Geolo...

  12. Comparative assessment of herbicide and fungicide runoff risk: a case study for peanut production in the Southern Atlantic Coastal Plain (USA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanut (Arachis hypogaea) is produced intensively in the southern Atlantic Coastal Plain of the eastern USA. To effectively protect the region’s water quality data are needed which quantify runoff of pesticides used to protect these crops. Fungicides are used intensively yet there is little publishe...

  13. ESTIMATING THE LIKELIHOOD OF OCCURRENCE OF SELECTED PESTICIDES AND NUTRIENTS EXCEEDING SPECIFIC CONCENTRATIONS IN COASTAL PLAIN STREAMS BASED ON LANDSCAPE CHARACTERISTICS

    EPA Science Inventory

    The occurrence of selected pesticides and nutrient compounds in nontidal headwater streams of the Mid-Atlantic Coastal Plain (North Carolina through New Jersey) during winter and spring base flow is related to land use, soils, and other geographic variables that reflect sources a...

  14. PREDICTING THE OCCURRENCE OF NUTRIENTS AND PESTICIDES DURING BASE FLOW IN NONTIDAL HEADWATER STREAMS OF THE MID-ATLANTIC COASTAL PLAIN

    EPA Science Inventory

    Water quality in nontidal headwater (first-order) streams of the Mid-Atlantic Coastal Plain (MACP) during base flow in the late winter and spring is related to land use, hydrogeology, and other natural or human influences in contributing watersheds.

  15. MEASURING BASE-FLOW CHEMISTRY AS AN INDICATOR OF REGIONAL GROUND-WATER QUALITY IN THE MID-ATLANTIC COASTAL PLAIN

    EPA Science Inventory

    Water quality in headwater (first-order) streams of the Mid-Atlantic Coastal Plain during base flow in the winter and spring is related to land use, hydrogeology, and other natural and human influences. A random survey of water quality in 174 headwater streams in the Mid-Atlantic...

  16. Wheat straw yield, nutrient uptake and soil chemical changes in two coastal plains ultisols amended with uncharred and pyrolyzed sorghum residues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current concerns about rising global population growth combined with global food security necessitate major optimization in agricultural management. The fertility of highly weathered Ultisols in the southeastern Coastal Plains region of United States is considerably low. In this region, intensive cr...

  17. Sedimentary and foraminiferal evidence of the 2011 Tōhoku-oki tsunami on the Sendai coastal plain, Japan

    NASA Astrophysics Data System (ADS)

    Pilarczyk, Jessica E.; Horton, Benjamin P.; Witter, Robert C.; Vane, Christopher H.; Chagué-Goff, Catherine; Goff, James

    2012-12-01

    The 2011 Tōhoku-oki megathrust earthquake (Mw 9.0) generated a tsunami that reached the Sendai coastal plain with flow heights of ~ 2 to 11 m above TP (Tokyo Peil). We examined the tsunami deposit exposed in 14 shallow trenches along a ~ 4.5-km transect perpendicular to the coast. We primarily document the stratigraphical, sedimentological, foraminiferal and geochemical characteristics of the Tōhoku-oki tsunami deposit and perform a preliminary comparison with sediments deposited by the Jōgan tsunami of A.D. 869. In the coastal forest and rice fields inundated by the Tōhoku-oki tsunami, a poorly sorted, dark brown soil is buried by a poorly sorted, brown, medium-grained sand deposit. In some trenches located more than 1.2 km inland, the sand is capped by a thin muddy-sand layer. The tsunami deposit, although highly variable in thickness, is generally thickest (25 cm) near the coastal dune and thins to less than 5 mm at ~ 4.5 km inland. The tsunami deposit was discriminated from the underlying soil by the appearance of recent and fossil foraminifera and a pronounced increase in grain size that fined upward and landward. The recent foraminifera preserved in the sandy facies of the deposit are rare and showed evidence of prolonged subaerial exposure (e.g. pitting, corrosion, fragmentation). Recent foraminifera likely originated from coastal dune and beach sediments that were breached by the tsunami. Calcified and sediment in-filled, fossil foraminifera are abundant and were eroded from sedimentary units and transported by fluvial or wave activity to Sendai Bay. Trends associated with test size (e.g. decreasing concentration of large test sizes with distance inland) are in agreement with grain size data. At two locations a decrease in total organic carbon and an increase in δ13C were found in the tsunami sand compared with the underlying soil, supporting a beach to intertidal origin for the upper unit.

  18. Regional chloride distribution in the Northern Atlantic Coastal Plain aquifer system from Long Island, New York, to North Carolina

    USGS Publications Warehouse

    Charles, Emmanuel G.

    2016-08-31

    Although additional offshore chloride data are available compared to 27 years ago (1989), the offshore information remains sparse, resulting in less confidence in the offshore interpretations than in the onshore interpretations. Regionally, the 250- and 10,000-mg/L isochlors tend to map progressively eastward from the deepest to the shallowest aquifers across the Northern Atlantic Coastal Plain aquifer system but with some exceptions. The additional data, conceptual understanding, and interpretations in the vicinity of the buried Chesapeake Bay impact structure in eastern Virginia resulted in substantial refinement of isochlors in that area. Overall, the interpretations in this study are updates of the previous regional study from 1989 but do not comprise major differences in interpretation and do not indicate regional movement of the freshwater-saltwater interface since then.

  19. Land-cover change in the Gulf Coastal Plains and Ozarks Landscape Conservation Cooperative, 1973 to 2000

    USGS Publications Warehouse

    Drummond, Mark A.; Stier, Michael P.; Coffin, Alisa W.

    2015-01-01

    This report summarizes baseline land-cover change information for four time intervals from between 1973 and 2000 for the Gulf Coastal Plains and Ozarks Landscape Conservation Cooperative (LCC). The study used sample data from the USGS Land Cover Trends dataset to develop estimates of change for 10 land-cover classes in the LCC. The results show that an estimated 17.7 percent of the LCC land cover had a change during the 27-year period. Cyclic forest dynamics—of timber harvest and regrowth—are the most extensive types of land conversion. Agricultural land had an estimated net decline of 3.5 percent as cropland and pasture were urbanized and developed and converted to forest use. Urban and other developed land covers expanded from 2.0 percent of the LCC in 1973 to 3.1 percent in 2000. The report also highlights causes and challenges of land-cover change.

  20. Excess in precipitation as a cause for settlement decline along the Israeli coastal plain during the third millennium BC

    NASA Astrophysics Data System (ADS)

    Faust, Avraham; Ashkenazy, Yosef

    2007-07-01

    Although the relations between climate and settlement are not straightforward, there is a general agreement that arid conditions are less favorable for human settlement in the semiarid Near East than humid conditions. Here we show that humid conditions resulted in the abandonment of settlements along the Israeli coastal plain. We first present archaeological evidence for a drastic decline in settlement along the Israeli coast during most of the third millennium BC (Early Bronze Age II-III). Then, based on archaeological and climatic evidence, we link this decline to an environmental change occurring at that time. We propose that increased precipitation intensified the already existing drainage problems and resulted in flooding, which led to the transformation of arable land into marshes and to the spread of diseases, gradually causing settlement decline and abandonment.

  1. National water quality assessment of the Georgia-Florida Coastal Plain study unit; water withdrawals and treated wastewater discharges, 1990

    USGS Publications Warehouse

    Marella, R.L.; Fanning, J.L.

    1996-01-01

    The Georgia-Florida Coastal Plain study unit covers nearly 62,600 square miles along the southeastern United States coast in Georgia and Florida. In 1990, the estimated population of the study unit was 9.3 million, and included all or part of the cities of Atlanta, Jacksonville, Orlando, Tampa, and St. Petersburg. Estimated freshwater withdrawn in the study unit in 1990 was nearly 5,075 million gallons per day. Ground-water accounted for more than 57 percent of the water withdrawn during 1990 and the Floridan aquifer system provided nearly 91 percent of the total ground-water withdrawn. Surface-water accounted for nearly 43 percent of the water withdrawn in the study unit in 1990 with large amounts of withdrawals from the Altamaha River, Hillsborough River, the Ocmulgee River, the Oconee River, the St. Johns River, and the Suwannee River. Water withdrawn for public supply in the Georgia-Florida Coastal Plain study unit in 1990 totaled 1,139 million gallons per day, of which 83 percent was ground water and 17 percent was surface water. Self-supplied domestic withdrawals in the Georgia-Florida Coastal Plain study unit in 1990 totaled nearly 230 million gallons per day. Ground water supplied over 80 percent of the study units population for drining water purposes; nearly 5.8 million people were served by public supply and 1.8 million people were served by self-supplied systems. Water withdrawn for self-supplied domestic use in Georgia and Florida is derived almost exclusively from ground water, primarily because this source can provide the quantity and quality of water needed for drinking purposes. Nearly 1.7 million people served by public supply utilized surface water for their drinking water needs. Water withdrawn for self-supplied commercial-industrial uses in the study unit in 1990 totaled 862 million gallons per day, of which 93 percent was ground water and 7 percent was surface water. Water withdrawn for agriculture purposes in the study unit in 1990 totaled 1

  2. Effects of basin type on coastal plain-shelf-slope systems during base-level fluctuations: An experimental approach

    SciTech Connect

    Wood, L.J. )

    1991-03-01

    Sequence stratigraphic models emphasize the importance of basin type on the reactions of coastal plain-shelf-slope systems to base-level changes. A series of experiments were performed in a 4.5 m by 7 m flume to examine the effects of a passive margin basin with a shelf/slope break versus a ramp margin basin on coastal plain-shelf-slope deposits that result from base-level fluctuations. Results indicate that basin type has a strong influence on the erosional features and deposits that develop in response to base-level fluctuations. Fluctuations that occur along a shelf/slope break margin result in well-defined, deeply incised valleys, which develop early in lowstand time and have low width:depth ratios. Rivers may incise into and deposit over outer-middle shelf deposits of the previous highstand. Late lowstand deposits are coarser grained than early lowstand deposits and include fine- and coarse-grained slope and basin floor fans. During subsequent base-level rise early transgressive deposits are confined to incised valleys. Fluctuations along a ramp margin result in shallow, wide incised valleys with high width:depth ratios, which develop late in lowstand time. Incision occurs into shelf deltaic deposits and these are overlain by valley fill deposits. Deposits of the lowstand systems tract do not coarsen upward significantly and contain only sand-rich, small, thin delta front fan deposits. During subsequent base-level rise transgressive deposits are not confined to incised valleys. Transgressive deposition within the valleys occurs over a short time interval and is followed closely by flooding of the adjacent shelf.

  3. Late Pleistocene to Holocene environmental changes as recorded in the sulfur geochemistry of coastal plain sediments, southwestern Taiwan

    USGS Publications Warehouse

    Chen, Y.-G.; Liu, J.C.-L.; Shieh, Y.-N.; Liu, T.-K.

    2004-01-01

    A core, drilled at San-liao-wan in the southwestern coastal plain of Taiwan, has been analyzed for total sulfur contents, isotopic values, as well as ratios of pyritic sulfur to organic carbon. Our results demonstrate a close relationship between late Pleistocene sea-level change and the proxies generated in this study. The inorganic sulfur contents indicate that at our study site, the Holocene transgression started at ???11 ka and remained under seawater for thousands of years until the late Holocene, corresponding to a depth of 20 m in the study core. The uppermost 20 m of core shows relatively high total organic carbon (TOC) and ??34S of inorganic sulfur, suggesting a transitional environment such as muddy lagoon or marsh, before the site turned into a modern coastal plain. In the lower part of the core, at depths of 110-145 m (corresponding ages of ???12-30 ka), low sulfur contents are recorded, probably indicating fluvial sediments deposited during the oceanic isotope stage (OIS) 2, a sea-level lowstand. The lower part of the core, roughly within OIS 3, records at least two transgressions, although the transgressional signals may be somewhat obscured by subsequent weathering. The reworked origin of organic matter reported in previous studies is confirmed by our organic sulfur data; however, the marine organic source was periodically dominant. The modern high sulfate concentrations in pore water have no correlation to the other sulfur species in the sediments, probably indicating that the sulfate migrated into the site subsequent to early diagenesis. ?? 2003 Elsevier Ltd. All rights reserved.

  4. Pathways for arsenic from sediments to groundwater to streams: Biogeochemical processes in the Inner Coastal Plain, New Jersey, USA

    USGS Publications Warehouse

    Barringer, Julia L.; Mumford, Adam; Young, Lily Y.; Reilly, Pamela A.; Bonin, Jennifer L.; Rosman, Robert

    2010-01-01

    The Cretaceous and Tertiary sediments that underlie the Inner Coastal Plain of New Jersey contain the arsenic-rich mineral glauconite. Streambed sediments in two Inner Coastal Plain streams (Crosswicks and Raccoon Creeks) that traverse these glauconitic deposits are enriched in arsenic (15–25 mg/kg), and groundwater discharging to the streams contains elevated levels of arsenic (>80 μg/L at a site on Crosswicks Creek) with arsenite generally the dominant species. Low dissolved oxygen, low or undetectable levels of nitrate and sulfate, detectable sulfide concentrations, and high concentrations of iron and dissolved organic carbon (DOC) in the groundwater indicate that reducing environments are present beneath the streambeds and that microbial activity, fueled by the DOC, is involved in releasing arsenic and iron from the geologic materials. In groundwater with the highest arsenic concentrations at Crosswicks Creek, arsenic respiratory reductase gene (arrA) indicated the presence of arsenic-reducing microbes. From extracted DNA, 16s rRNA gene sequences indicate the microbial community may include arsenic-reducing bacteria that have not yet been described. Once in the stream, iron is oxidized and precipitates as hydroxide coatings on the sediments. Arsenite also is oxidized and co-precipitates with or is sorbed to the iron hydroxides. Consequently, dissolved arsenic concentrations are lower in streamwater than in the groundwater, but the arsenic contributed by groundwater becomes part of the arsenic load in the stream when sediments are suspended during high flow. A strong positive relation between concentrations of arsenic and DOC in the groundwater samples indicates that any process—natural or anthropogenic—that increases the organic carbon concentration in the groundwater could stimulate microbial activity and thus increase the amount of arsenic that is released from the geologic materials.

  5. End-Pleistocene Soil Constituents from Selected Sites on the Mid-Atlantic Coastal Plain: First Results

    NASA Astrophysics Data System (ADS)

    Lecompte, M. A.; Rock, B. N.; Demitroff, M.; Reid, M.; Lucas, L.; Hughes, D.; Hayden, L. B.

    2008-12-01

    Stratigraphic analyses of soil samples taken from dated and undated sites located along the mid-Atlantic Coastal Plain have yielded evidence of increased contemporary biomass burning, compared to under and overlying strata. Host strata ages are known or projected to bracket the onset of the Younger Dryas cooling episode at 12.9 cal ka. This ongoing investigation includes samples from: 1) a late-Pleistocene aged periglacial feature located within the Pine Barrens of southern New Jersey; 2) an artifact dated stratum (~ 12.9 ka) in an embankment on the Chesapeake Bay in Maryland; and 3) an as yet undated (C14 test results pending) embankment of the Perquimans River in northeastern North Carolina projected to be age-appropriate. Sample analysis of scanning electron (SEM) micrographs from the Chesapeake Bay site revealed charred fragments of late-Wisconsinan Krummholz birch (Betula) and species of spruce (Picea) and fir (Abies), which are not extant on the modern-day, temperate Coastal Plain. In addition, organic faunal material is found in association with ancient charred boreal wood, including hollow hair and skin fragments that are as yet unidentified, perhaps from cold climate adapted animals as inferred from host sediment age. Charred wood fragments are found to be attracted to a neodymium magnet. Some aggregates of organic matter appear to contain magnetic spherule-like grains whose composition is awaiting geochemical analysis. Photomicrographs of all specimens and a stratigraphic breakdown in the relative amount of burned carbon associated with each site and strata will be presented, along with the results of various analyses that are currently underway.

  6. Natural and Human Influences on Water Quality in a Shallow Regional Unconsolidated Aquifer, Northern Atlantic Coastal Plain

    USGS Publications Warehouse

    Ator, Scott W.

    2008-01-01

    Data collected from more than 400 wells in the surficial unconfined aquifer in the Northern Atlantic Coastal Plain (New York through North Carolina) were compiled and analyzed to improve understanding of multiple natural and human influences on water quality in such shallow regional aquifers. Geochemical patterns were identified and described through principal components analysis on major ions, and correlation and logistic regression were used to relate observed concentrations of nitrate and selected pesticide compounds (atrazine, metolachlor, simazine, and deethylatrazine, an atrazine degradate) and volatile organic compounds (chloroform, 1,1,1-trichloroethane, tetrachlorethene, and methyl tert-butyl ether) to likely influences, such as observed geochemical patterns, land use, hydrogeology, and soils. Variability in major-ion concentrations is primarily related to ionic strength and redox condition. Concentrations of nitrate, pesticides, and volatile organic compounds are related to natural conditions, as well as the distribution of likely sources reflected in land use. Nitrate is most common in aerobic ground water and in relatively well-drained areas, for example; concentrations greater than 0.4 milligrams per liter may result from a variety of human activities, although concentrations greater than 3 milligrams per liter are more likely in agricultural areas. Atrazine, deethylatrazine, and metolachlor also are related to geochemical patterns, likely because ground-water geochemistry reflects hydrogeologic and soil conditions affecting pesticide transport to the water table. Results demonstrate the value of geochemical information along with the distribution of sources and other influences to understanding the regional occurrence of selected compounds in ground water. Such influences are not unique to the Northern Atlantic Coastal Plain, and thus observations and interpretations are relevant to broader areas.

  7. The Collins Creek and Pleasant Creek Formations: Two new upper cretaceous subsurface units in the Carolina/Georgia Coastal Plain

    USGS Publications Warehouse

    ,; Prowell, D.C.; Christopher, R.A.

    2004-01-01

    This paper formally defines two new Upper Cretaceous subsurface units in the southern Atlantic Coastal Plain of North Carolina, South Carolina and Georgia: the Collins Creek Formation and the Pleasant Creek Formation. These units are confined to the subsurface of the outer Coastal Plain, and their type sections are established in corehole CHN-820 from Charleston County, S.C. The Collins Creek Formation consists of greenish-gray lignitic sand and dark-greenish-gray sandy clay and is documented in cores from Allendale, Beaufort, Berkeley, Dorchester, Jasper and Marion Counties, South Carolina, and from Screven County, Georgia. Previously, Collins Creek strata had been incorrectly assigned to the Middendorf Formation. These sediments occupy a stratigraphic position between the Turonian/Coniacian Cape Fear Formation (?) below and the proposed upper Coniacian to middle Santonian Pleasant Creek Formation above. The Collins Creek Formation is middle and late Coniacian in age on the basis of calcareous nannofossil and palynomorph analyses. The Pleasant Creek Formation consists of olive-gray sand and dark-greenish-gray silty to sandy clay and is documented in cores from New Hanover County, North Carolina, and Berkeley, Charleston, Dorchester, Horry and Marion Counties, South Carolina. The strata of this unit previously were assigned incorrectly to the Middendorf Formation and (or) the Cape Fear Formation. These sediments occupy a stratigraphic position between the proposed Collins Creek Formation below and the Shepherd Grove Formation above. The Pleasant Creek Formation is late Coniacian and middle Santonian in age, on the basis of its calcareous nannofossil and palynomorph assemblages.

  8. Effects of Late Cretaceous and Cenozoic faulting on the geology and hydrology of the coastal plain near the Savannah River, Georgia and South Carolina

    USGS Publications Warehouse

    Faye, R.E.; Prowell, D.C.

    1982-01-01

    Geologic and hydrologic investigations by the U.S. Geological Survey have defined stratigraphic and hydraulic anomalies suggestive of faulting within Coastal Plain sediments between the Ogeechee River in east-central Georgia and the Edisto River in west-central South Carolina. Examination of borehole cuttings, cores, and geophysical logs from test wells indicate that Triassic rocks and Upper Cretaceous and lower Tertiary Coastal Plain sediments near the Barnwell-Allendale County line near Millett, South Carolina, are offset by a northeast-trending fault downthrown to the northwest. The location of this suspected Coastal Plain fault generally coincides with the location of an inferred fault in basement rocks as interpreted from aeromagnetic surveys. Apparent vertical offsets range from about 700 feet at the base of Upper Cretaceous sediments to about 20 feet in strata of Late Eocene age. As a result, the Upper Cretaceous Middendorf Formation which directly overlies crystalline and Triassic rocks updip (northwest) of this fault, is absent immediately downdip of the fault. The thickness of Tipper Cretaceous sediments is also sharply reduced from about 700 feet to about 180 feet across the fault. Sediments of the basal Coastal Plain aquifer are largely truncated by uplifted Triassic rocks at the fault near Millett, South Carolina. Lateral ground-water flow near the Savannah River Is consequently disrupted updip of the fault and ground water is transferred vertically into overlying sediments and possibly into the Savannah River. At several locations, abrupt changes in potentiometric head occur across this fault. Computed transmissivity of the basal Coastal Plain aquifer is also radically reduced downdip of the fault, sharply reversing a downdip trend of rapidly increasing aquifer transmissivity. Other anomalous potentiometric data along a northeast-trending line between Statesboro, Georgia, and Fairfax, South Carolina, suggest the possibility of similar faulting in

  9. Water-Level Conditions in Selected Confined Aquifers of the New Jersey and Delaware Coastal Plain, 2003

    USGS Publications Warehouse

    dePaul, Vincent T.; Rosman, Robert; Lacombe, Pierre J.

    2009-01-01

    The Coastal Plain aquifers of New Jersey provide an important source of water for more than 2 million people. Steadily increasing withdrawals from the late 1800s to the early 1990s resulted in declining water levels and the formation of regional cones of depression. In addition to decreasing water supplies, declining water levels in the confined aquifers have led to reversals in natural hydraulic gradients that have, in some areas, induced the flow of saline water from surface-water bodies and adjacent aquifers to freshwater aquifers. In 1978, the U.S. Geological Survey began mapping the potentiometric surfaces of the major confined aquifers of New Jersey every 5 years in order to provide a regional assessment of ground-water conditions in multiple Coastal Plain aquifers concurrently. In 1988, mapping of selected potentiometric surfaces was extended into Delaware. During the fall of 2003, water levels measured in 967 wells in New Jersey, Pennsylvania, northeastern Delaware, and northwestern Maryland were used estimate the potentiometric surface of the principal confined aquifers in the Coastal Plain of New Jersey and five equivalent aquifers in Delaware. Potentiometric-surface maps and hydrogeologic sections were prepared for the confined Cohansey aquifer of Cape May County, the Rio Grande water-bearing zone, the Atlantic City 800-foot sand, the Vincentown aquifer, and the Englishtown aquifer system in New Jersey, as well as for the Piney Point aquifer, the Wenonah-Mount Laurel aquifer, and the Upper Potomac-Raritan-Magothy, the Middle and undifferentiated Potomac-Raritan-Magothy, and the Lower Potomac-Raritan-Magothy aquifers in New Jersey and their equivalents in Delaware. From 1998 to 2003, water levels in many Coastal Plain aquifers in New Jersey remained stable or had recovered, but in some areas, water levels continued to decline as a result of pumping. In the Cohansey aquifer in Cape May County, water levels near the center of the cone of depression

  10. Surface waves in the western Taiwan coastal plain from an aftershock of the 1999 Chi-Chi, Taiwan, earthquake

    USGS Publications Warehouse

    Wang, G.-Q.; Tang, G.-Q.; Boore, D.M.; Van Ness, Burbach; Jackson, C.R.; Zhou, X.-Y.; Lin, Q.-L.

    2006-01-01

    Significant surface waves were recorded in the western coastal plain (WCP) of Taiwan during the 1999 Chi-Chi, Taiwan, earthquake and its series of aftershocks. We study in detail the surface waves produced by one aftershock (20 September 1999, 18hr 03m 41.16sec, M 6.2) in this paper. We take the Chelungpu-Chukou fault to be the eastern edge of the WCP because it marks a distinct lateral contrast in seismic wave velocities in the upper few kilometers of the surface. For many records from stations within the WCP, body waves and surface waves separate well in both the time domain and the period domain. Long-period (e.g., >2 sec) ground motions in the plain are dominated by surface waves. Significant prograde Rayleigh wave particle motions were observed in the WCP. The observed peak ground velocities are about 3-5 times larger than standard predictions in the central and western part of the plain. Observed response spectra at 3 sec, 4 sec, and 5 sec at the center of the plain can be 15 times larger than standard predictions and 10 times larger than the predictions of Joyner (2000) based on surface wave data from the Los Angeles basin. The strong surface waves were probably generated at the boundary of the WCP and then propagated toward the west, largely along radial directions relative to the epicenter. The geometry of the boundary may have had a slight effect on propagation directions of surface waves. Group velocities of fundamental mode Rayleigh and Love waves are estimated using the multiple filter analysis (MFA) technique and are refined with phase matched filtering (PMF). Group velocities of fundamental mode surface waves range from about 0.7 km/sec to 1.5 km/sec for the phases at periods from 3 sec to 10 sec. One important observation from this study is that the strongest surface waves were recorded in the center of the plain. The specific location of the strongest motions depends largely on the period of surface waves rather than on specific site conditions or

  11. Nitrogen Bsalance for a Plantation Forest Drainage Canal on the North Carolina Coastal Plain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Human alteration of the nitrogen cycle has led to increased riverine nitrogen loads, contributing to the eutrophication of lakes, streams, estuaries, and near-coastal oceans. These riverine nitrogen loads are usually less than the total nitrogen inputs to the system, indicating nitrogen removal duri...

  12. Fate and surface transport of urea in a coastal plain soil: a rainfall simulation study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The surface transport of urea has rarely been studied since it is assumed to undergo rapid hydrolysis to ammonia. However, studies have shown urea to exist in estuarine and coastal waters. Urea in small amounts can trigger the diatom Pseudo-nitzschia spp. to produce the toxin domoic acid, which is o...

  13. Persistence of urea in a coastal plain soil: an incubation study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Urea-based nitrogen sources can possibly lead to nutrient pollution of various water bodies due to leaching and runoff, and also trigger the diatom Pseudo-nitzschia spp. to produce shellfish poisoning. This causes economic and human health concerns in the Chesapeake Bay and other coastal regions. Ur...

  14. Assessment of groundwater availability in the Northern Atlantic Coastal Plain aquifer system From Long Island, New York, to North Carolina

    USGS Publications Warehouse

    Masterson, John P.; Pope, Jason P.; Fienen, Michael N.; Monti, Jr., Jack; Nardi, Mark R.; Finkelstein, Jason S.

    2016-08-31

    Executive SummaryThe U.S. Geological Survey began a multiyear regional assessment of groundwater availability in the Northern Atlantic Coastal Plain (NACP) aquifer system in 2010 as part of its ongoing regional assessments of groundwater availability of the principal aquifers of the Nation. The goals of this national assessment are to document effects of human activities on water levels and groundwater storage, explore climate variability effects on the regional water budget, and provide consistent and integrated information that is useful to those who use and manage the groundwater resource. As part of this nationwide assessment, the USGS evaluated available groundwater resources within the NACP aquifer system from Long Island, New York, to northeastern North Carolina.The northern Atlantic Coastal Plain physiographic province depends heavily on groundwater to meet agricultural, industrial, and municipal needs. The groundwater assessment of the NACP aquifer system included an evaluation of how water use has changed over time; this evaluation primarily used groundwater budgets and development of a numerical modeling tool to assess system responses to stresses from future human uses and climate trends.This assessment focused on multiple spatial and temporal scales to examine changes in groundwater pumping, storage, and water levels. The regional scale provides a broad view of the sources and demands on the system with time. The sub-regional scale provides an evaluation of the differing response of the aquifer system across geographic areas allowing for closer examination of the interaction between different aquifers and confining units and the changes in these interactions under pumping and recharge conditions in 2013 and hydrologic stresses as much as 45 years in the future. By focusing on multiple scales, water-resource managers may utilize this study to understand system response to changes as they affect the system as a whole.The NACP aquifer system extends from

  15. Does Reactivation of Louisiana's Chenier Plain Lead to the Development of Interior Coastal Wetlands? Assessing the Relative Roles of Storm Impacts and Riverine Deposits

    NASA Astrophysics Data System (ADS)

    Ramatchandirane, C. G.; Kolker, A.; Ameen, A. D.; Williams, K.; Donnelly, J. P.; Giosan, L.

    2010-12-01

    At the beginning of the 20th century, increased flow into the Atchafalaya River from the Mississippi River reactivated sediment dynamics along the Chenier Plain. The Chenier Plain is a microtidal, storm-dominated coastal environment situated west and downdrift of the Mississippi River Delta. Composed of alternating mudflats, marsh, and elevated “chenier” (oak) ridges, this coastal system provides an ideal case study to both investigate the success of the Atchafalaya River diversion in building wetlands, and to construct a chronology of storm impacts on the Louisiana Gulf coast. To examine whether and how the reactivation of the Chenier Plain has impacted sediment dynamics in coastal wetlands, sediment cores from Miller Lake in the Chenier Plain were analyzed. Historic photos and maps of Miller Lake show open water in an area now dominated by marsh. The recent filling in of Miller Lake suggests new deposition by a possible combination of storm impacts and riverine deposits. In this study, carbonate deposition is used as a proxy for marine-dominated sedimentation, which reflects the shelly marine-dominated coastal environment of the Chenier Plain. Grain size analysis data was collected to distinguish sand layers from possible overwash deposits of storm impacts. Rates of sediment accretion and mineral deposition were determined using the naturally occurring radioisotope 210Pb. The collected sediment cores indicate new marsh developing over muddy sediments. In contrast to SE Louisiana’s high rates of wetland loss, this study points to evidence of wetland accretion in SW Louisiana as a result of the Atchafalaya River diversion.

  16. Proposed oil and gas exploration within the coastal plain of the Arctic National Wildlife Refuge, Alaska

    SciTech Connect

    Not Available

    1982-11-01

    The draft environmental impact statement describes the procedures and probable effects of aerial and geological surveying for oil and gas in the coastal area of Alaska's Arctic National Wildlife Refuge. The procedures provide for the protection of caribou caving areas and the avoidance of duplication in the survey activities. Temporary disturbances from seismic surveys would interfere with wildlife breeding and migration due to changes in the habitat. The Alaska National Interest Lands Conservation Act of 1980 provides the legal mandate for environmental assessment.

  17. Coastal deformation between the Versilia and the Garigliano plains (Italy) since the last interglacial stage

    NASA Astrophysics Data System (ADS)

    Nisi, Marco F.; Antonioli, Fabrizio; Pra, Giuseppe Dai; Leoni, Gabriele; Silenzi, Sergio

    2003-12-01

    The opening of the north-central Tyrrhenian Sea is the result of the Cretaceous-Paleogene alpine collision, which triggered a series of regional uplift, subsidence and transcurrent tectonic mechanisms along the coastal Tyrrhenian sectors of peninsular Italy. These tectonic processes, in conjunction with the effects of glacio- and hydro-isostasy during the Quaternary, produced substantial crustal responses that, in some cases, reached metres in extent. In the study of coastal neotectonics, geomorphological markers of the last interglacial maximum, corresponding to marine isotope stage 5.5, are generally used to quantify the magnitude of the vertical crustal displacements that have occurred since 125 kyr. Through altimetrical, palaeoenvironmental and chronological reinterpretation of the most significant works published since 1913, combined with an additional set of data reported here, a detailed reconstruction of the shoreline displacements evident along 500 km of coast between northern Tuscany and southern Latium is presented. The reconstruction was carried out by quantifying the vertical movement since the last interglacial period and by identifying the tectonic behaviour of different coastal sectors. This has been done by carefully choosing the eustatic marker, among those available at each study site, in order to minimize the margin of error associated with the measurements. Copyright

  18. Dinoflagellate species and organic facies evidence of marine transgression and regression in the atlantic coastal plain

    USGS Publications Warehouse

    Habib, D.; Miller, J.A.

    1989-01-01

    Palynological evidence is used to date and interpret depositional environments of sediments of Campanian, Maestrichtian and early Danian ages cored in three wells from South Carolina and Georgia. The evidence is usefil for distinguishing environments which lithofacies evidence indicates a range from nonmarine to coastal to inner neritic shallow shelf. Numerous dinoflagellate species and an organic facies defined abundant amoprphous debris (amorphous debris facies) distinguish shallow shelf sediments deposited during marine transgression. The nearshore amorphous debris facies of late Campanian age consists of heterogenous assemblages dominated by Palaeohystrichophora infusorioides Deflandre or Hystrichosphaerina varians (May). The farther offshore amorphous debris facies of late early Maestrichtian to late Maestrichtian age consists of heterogenous assemblages dominated by Glaphyrocysta retiintexta (Cookson) and/or Areoligera medusettiformis (Wetzel). The larger number of dinoflagellate species in the offshore facies represents the maximum transgression detected in the investigated interval. A multiple occurrence datum defined by the combination of first appearance, klast appearances and sole occurrence of dinoflagellate species at the base of each interval distinguished by the amorphous debris facies provides the first evidence of marine transgression. Relatively small organic residues consisting of intertinite and few or no palynomorphs define the inertinite facies in nonmarine deltaic and in coastal (lagoonal, tidal flat, interdistributary bary) sediments. Dinocyt{star, open}s are absent in the nonmarine sediments and are represented by few species and few specimens in the coastal inertinite faceis. A third organic facies (vascular tissue facies) is defined by the abundance of land plant tissue. Sporomorph species, including those of the Normapolles pollen group and of pteridophyte spores, comprise a large proportion of the total palynomorph flora in the

  19. Geophysical modeling of the northern Appalachian Brompton-Cameron, Central Maine, and Avalon terranes under the New Jersey Coastal Plain

    USGS Publications Warehouse

    Maguire, T.J.; Sheridan, R.E.; Volkert, R.A.

    2004-01-01

    A regional terrane map of the New Jersey Coastal Plain basement was constructed using seismic, drilling, gravity and magnetic data. The Brompton-Cameron and Central Maine terranes were coalesced as one volcanic island arc terrane before obducting onto Laurentian, Grenville age, continental crust in the Taconian orogeny [Rankin, D.W., 1994. Continental margin of the eastern United States: past and present. In: Speed, R.C., (Ed.), Phanerozoic Evolution of North American Continent-Ocean Transitions. DNAG Continent-Ocean Transect Volume. Geological Society of America, Boulder, Colorado, pp. 129-218]. Volcanic island-arc rocks of the Avalon terrane are in contact with Central Maine terrane rocks in southern Connecticut where the latter are overthrust onto the Brompton-Cameron terrane, which is thrust over Laurentian basement. Similarities of these allochthonous island arc terranes (Brompton-Cameron, Central Maine, Avalon) in lithology, fauna and age suggest that they are faulted segments of the margin of one major late Precambrian to early Paleozoic, high latitude peri-Gondwana island arc designated as "Avalonia", which collided with Laurentia in the early to middle Paleozoic. The Brompton Cameron, Central Maine, and Avalon terranes are projected as the basement under the eastern New Jersey Coastal Plain based on drill core samples of metamorphic rocks of active margin/magmatic arc origin. A seismic reflection profile across the New York Bight traces the gentle dipping (approximately 20 degrees) Cameron's Line Taconian suture southeast beneath allochthonous Avalon and other terranes to a 4 sec TWTT depth (approximately 9 km) where the Avalonian rocks are over Laurentian crust. Gentle up-plunge (approximately 5 degrees) projections to the southwest bring the Laurentian Grenville age basement and the drift-stage early Paleozoic cover rocks to windows in Burlington Co. at approximately 1 km depth and Cape May Co. at approximately 2 km depths. The antiformal Shellburne

  20. Cenozoic global sea level, sequences, and the New Jersey transect: Results from coastal plain and continental slope drilling

    USGS Publications Warehouse

    Miller, K.G.; Mountain, Gregory S.; Browning, J.V.; Kominz, M.; Sugarman, P.J.; Christie-Blick, N.; Katz, M.E.; Wright, J.D.

    1998-01-01

    The New Jersey Sea Level Transect was designed to evaluate the relationships among global sea level (eustatic) change, unconformity-bounded sequences, and variations in subsidence, sediment supply, and climate on a passive continental margin. By sampling and dating Cenozoic strata from coastal plain and continental slope locations, we show that sequence boundaries correlate (within ??0.5 myr) regionally (onshore-offshore) and interregionally (New Jersey-Alabama-Bahamas), implicating a global cause. Sequence boundaries correlate with ??18O increases for at least the past 42 myr, consistent with an ice volume (glacioeustatic) control, although a causal relationship is not required because of uncertainties in ages and correlations. Evidence for a causal connection is provided by preliminary Miocene data from slope Site 904 that directly link ??18O increases with sequence boundaries. We conclude that variation in the size of ice sheets has been a primary control on the formation of sequence boundaries since ~42 Ma. We speculate that prior to this, the growth and decay of small ice sheets caused small-amplitude sea level changes (<20 m) in this supposedly ice-free world because Eocene sequence boundaries also appear to correlate with minor ??18O increases. Subsidence estimates (backstripping) indicate amplitudes of short-term (million-year scale) lowerings that are consistent with estimates derived from ??18O studies (25-50 m in the Oligocene-middle Miocene and 10-20 m in the Eocene) and a long-term lowering of 150-200 m over the past 65 myr, consistent with estimates derived from volume changes on mid-ocean ridges. Although our results are consistent with the general number and timing of Paleocene to middle Miocene sequences published by workers at Exxon Production Research Company, our estimates of sea level amplitudes are substantially lower than theirs. Lithofacies patterns within sequences follow repetitive, predictable patterns: (1) coastal plain sequences consist

  1. Digital-simulation model of the Wenonah-Mount Laurel Aquifer in the coastal plain of New Jersey

    USGS Publications Warehouse

    Nemickas, Bronius

    1976-01-01

    A digital computer-simulation model of the Wenonah-Mount Laurel aquifer is used to evaluate the aquifer's capabilities of meeting the projected future demands and to study the cause of the rapidly declining water levels. The modelled area includes 1,500 square miles (3,885 square kilometres) of the New Jersey Coastal Plain and includes all the important centers of pumping in Monmouth, Burlington, and Ocean Counties from the Wenonah-Mount Laurel aquifer. The Wenonah Formation and Mount Laurel Sand of Late Cretaceous age are exposed in the western part of the New Jersey Coastal Plain along a belt trending northeast-southwest from Raritan Bay to Delaware Bay. The formations typically consist of poorly sorted silty to fine quartz sand, the Wenonah Formation, and a coarse clastic quartz sand unit, the Mount Laurel Sand. The Wenonah-Mount Laurel aquifer is composed of the sandy part of the geologic units. Transmissivity of the aquifer ranges from 360 square feet per day (33.4 square metres per day) to 1,430 square feet per day (132.8 square metres per day); the estimated hydraulic conductivity ranges from about 1.5 x 10-4 feet per second (4.6 x 10-5 metres per second) to 2.2 x 10-4 feet per second (6.7 x 10-5 metres per second); and the storage coefficient varies from about 1.5 x 10-5 to 3.5 x 10-4. The annual average rate of withdrawal from the Wenonah-Mount Laurel aquifer in Monmouth, Burlington, and Ocean Counties increased from about 1 million gallons per day (44 cubic decimetres per second) in 1959 to slightly more than 2 million gallons per day (88 cubic decimetres per second) in 1970. Near the pumping centers in Monmouth County, the water level declined as much as 100 feet (30.5 metres) between 1959 and 1970. In the subjacent Englishtown aquifer underlying the lower confining unit (Marshalltown Formation), the annual average rate of withdrawal in all of Monmouth and Ocean Counties increased from 5.5 million gallons per day (241 cubic decimetres per second) in 1959

  2. A Comparative Analysis of Hydrologic Response to Climate Change in Developed and Undeveloped Watersheds on the New Jersey Coastal Plain

    NASA Astrophysics Data System (ADS)

    Daraio, J. A.

    2014-12-01

    Climate change is projected to have an impact on precipitation patterns across the Mid-Atlantic with the likelihood of an increase in the frequency and magnitude of extreme precipitation events. A greater proportion of total annual precipitation could fall in larger events with the potential to impact flooding, storm water infrastructure, and water supply. The watersheds of the coastal plain of New Jersey draining to the Atlantic and Delaware Bay have mild slopes are underlain by very sandy soils. These areas serve as sources of recharge to the Kirkwood-Cohansey aquifer, which is an important water supply for the region. The Precipitation-Runoff Modeling System (PRMS) was used to simulate the potential impacts of climate change on stream flow and groundwater recharge in two watersheds located within the New Jersey coastal plain. The Batsto River watershed includes parts of the Pinelands Reserve with relatively little development in some its headwater areas, primarily small towns and agricultural land use. The Maurice River watershed includes several urbanized areas along with some agricultural land, but population is expecting to increase within the next 10-20 years. The Maurice River basin is outside the Pinelands Reserve but has significant area that contains Pine Barrens. Models were calibrated using observed stream flow from USGS gages and gridded meteorological data from 1995-2002 and validated with observed data from 2002-2005. The calibrated models were forced using an ensemble of three bias-corrected downscaled climate projections (CMIP5, NOAA NCEP, and ECHAM) to assess and compare the potential response of these two watersheds. All meteorological data were obtained online from the GeoData Portal. Preliminary results indicate that climate change is likely to have a greater impact on stream flow in the developed Maurice River basin than in the undeveloped Batsto River basin. More detailed analyses of stream flow and the potential impacts on groundwater

  3. Biogeochemical and Hydrological Controls on Mercury and Methylmercury in First Order Coastal Plain Watersheds of the Chesapeake Bay

    NASA Astrophysics Data System (ADS)

    Heyes, A.; Gilmour, C. C.; Bell, J. T.; Butera, D.; McBurney, A. W.

    2015-12-01

    Over the past 7 years we made use of the long-term research site at the Smithsonian Environmental Research Center (SERC) in central Maryland to study the fluxes of mercury (Hg) and methylmercury (MeHg) in three small first-order mid-Atlantic coastal plain watersheds. One watershed is entirely forested, one watershed is primarily agriculture with a forested stream buffer, and one watershed is mixed land use but contains a beaver produced wetland pond. Our initial goals were to assess watershed Hg yields in the mid-Atlantic and to establish a baseline prior to implementation of Hg emissions controls. All three studied watersheds produced relatively high yields of Hg, with the greatest yield coming from the forested watershed. Our initial evaluation of three watersheds showed that MeHg production and flux could also be high, but varied dramatically among watersheds and across years and seasons. During each year we observed episodic MeHg production in the spring and sometimes during prolonged high-flow storm events in the fall. The observed spring maxima of MeHg release coincided with development of anoxia in riparian groundwater. MeHg accumulation in riparian groundwater began once nitrate was depleted and either iron accumulation or sulfate depletion of groundwater began. We propose the presence of nitrate was modulating MeHg production through the suppression of sulfate and iron reducers and perhaps methanogens. As sulfate is not limiting in any of the watersheds owing to the sediments marine origin, we hypothesize the depletion of nitrate allows sulfate reducing bacteria to now utilize available carbon. Although wetlands are generally thought of as the primary zones of MeHg production in watersheds, shallow riparian groundwaters very close to the stream appear to play that role in SERC Coastal Plain watersheds. We hypothesize that the balance between nitrate, sulfate and other microbial electron acceptors in watersheds is a major control on MeHg production. Land

  4. Analysis of nutrients in the surface waters of the Georgia-Florida Coastal Plain study unit, 1970-91

    USGS Publications Warehouse

    Ham, L.K.; Hatzell, H.H.

    1996-01-01

    Aucilla River basin had the lowest. Median concentrations of nitrate and ammonia among all major basins were below USEPA guidelines. The median total-phosphorus concentrations for the following river basins exceeded the USEPA guideline-Hillsborough, St. Johns, Suwannee, Ochlockonee, Satilla, Altamaha, and Ogeechee. Although nutrient concentrations within the study unit were low, long-term increasing trends were found in all four nutrients. All 18 study-unit wide nitrate trends had increasing slopes ranging from less than 0.01 to 0.07 (mg/L)/yr. The range in slope for the 13 ammonia trends was -0.03 to 0.01 (mg/L)/yr with 6 increasing trends in the northern part of the study unit. Of the 17 total-phosphorus trends found in the study unit, 10 were found at sites where the median concentration exceeded the USEPA guideline. At these 10 sites, 4 sites had increasing trends with slopes ranging from less than 0.01 to 0.07 (mg/L)/yr, 5 sites had decreasing trends with slopes ranging from -0.01 to -0.24 (mg/L)/yr, and one site showed a seasonal concentration trend. Median nutrient concentrations were significantly different among the four land resource provinces-Southern Piedmont, Southern Coastal Plain, Coastal Flatwoods, and Central Florida Ridge. As a result, nutrient concentrations among basins with similar nutrient inputs but located within different land resource provinces are not expected to be the same due to differences in the combination of factors such as soil permeability, runoff rates, and stream channel slopes. This concept is an important consideration in designing a surface-water quality network within the study area. For the most part, the Coastal Flatwoods showed the lowest median nutrient concentrations and the Southern Coastal Plain had the highest median nutrient concentrations. Lower median nitrate concentrations in surface-water basins were associated with the forest/wetland land-use category and higher median concentrations of nitrate and ammonia with

  5. Regional stratigraphy and subsurface geology of Cenozoic deposits, Gulf Coastal Plain, south-central United States

    USGS Publications Warehouse

    Hosman, R.L.

    1991-01-01

    Although Cenozoic deposits are not uniformly differentiated, interstate correlations of major Paleocene and Eocene units are generally established throughout the area. Younger deposits are not as well differentiated. Some stratigraphic designations made at surface exposures cannot be extended into the sub-surface, and the scarcity of distinct geologic horizons has hampered differentiation on a regional scale. The complexities of facies development in Oligocene and younger coastal deposits preclude the development of extensive recognizable horizons needed for stratigraphic applications. Coastal deposits are a heterogeneous assemblage of deltaic, lagoonal, lacustrine, palustrine, eolian, and fluvial clastic facies and local calcareous reef facies. Even major time boundaries, as between geologic series, are not fully resolved. Surficial Quaternary deposits overlie the truncated subcrops of Tertiary strata and generally are distinguishable, although some contacts between Pleistocene and underlying Pliocene deposits have been a ?lstoncal source of controversy. Glacially related terraces are characteristic of the Pleistocene Epoch, and alluvium of aggrading streams typifies the Holocene. 

  6. Hydrogeochemical features of groundwater of semi-confined coastal aquifer in Amol-Ghaemshahr plain, Mazandaran Province, Northern Iran.

    PubMed

    Khairy, Houshang; Janardhana, M R

    2013-11-01

    Hydrogeochemical data of groundwater from the semi-confined aquifer of a coastal two-tier aquifer in Amol-Ghaemshahr plain, Mazandaran Province, Northern Iran reveal salinization of the fresh groundwater (FGW). The saline groundwater zone is oriented at an angle to both Caspian Sea coastline and groundwater flow direction and extends inland from the coastline for more than 40 km. Spearman's rank correlation coefficient matrices, factor analysis data, and values of C ratio, chloro-alkaline indices, and Na(+)/Cl(-) molar ratio indicate that the ionic load in the FGW is derived essentially from carbonic acid-aided weathering of carbonates and aluminosilicate minerals, relict connate saline water, and ion exchange reactions. Saline groundwater samples (SGWS) (n = 20) can be classified into two groups. SGWS of group 1 (n = 17) represent the saline groundwater zone below the Caspian Sea level, and salinization is attributed essentially to (1) lateral intrusion of Caspian seawater as a consequence of (a) excessive withdrawal of groundwater from closely spaced bore wells located in the eastern part of the coastal zone and (b) imbalance between recharge and discharge of the two-tier aquifer and (2) upconing of paleobrine (interfaced with FGW) along deep wells. SGWS of this group contain, on average, 7.9% of saltwater, the composition of which is similar to that of Caspian seawater. SGWS of group 2 (n = 3) belong to the saline groundwater zone encountered above the Caspian Sea level, and salinization of the groundwater representing these samples is attributed to irrigation return flow (n = 2) and inflow of saline river water (n = 1).

  7. Validation of Satellite Precipitation (trmm 3B43) in Ecuadorian Coastal Plains, Andean Highlands and Amazonian Rainforest

    NASA Astrophysics Data System (ADS)

    Ballari, D.; Castro, E.; Campozano, L.

    2016-06-01

    Precipitation monitoring is of utmost importance for water resource management. However, in regions of complex terrain such as Ecuador, the high spatio-temporal precipitation variability and the scarcity of rain gauges, make difficult to obtain accurate estimations of precipitation. Remotely sensed estimated precipitation, such as the Multi-satellite Precipitation Analysis TRMM, can cope with this problem after a validation process, which must be representative in space and time. In this work we validate monthly estimates from TRMM 3B43 satellite precipitation (0.25° x 0.25° resolution), by using ground data from 14 rain gauges in Ecuador. The stations are located in the 3 most differentiated regions of the country: the Pacific coastal plains, the Andean highlands, and the Amazon rainforest. Time series, between 1998 - 2010, of imagery and rain gauges were compared using statistical error metrics such as bias, root mean square error, and Pearson correlation; and with detection indexes such as probability of detection, equitable threat score, false alarm rate and frequency bias index. The results showed that precipitation seasonality is well represented and TRMM 3B43 acceptably estimates the monthly precipitation in the three regions of the country. According to both, statistical error metrics and detection indexes, the coastal and Amazon regions are better estimated quantitatively than the Andean highlands. Additionally, it was found that there are better estimations for light precipitation rates. The present validation of TRMM 3B43 provides important results to support further studies on calibration and bias correction of precipitation in ungagged watershed basins.

  8. Digital elevations and extents of regional hydrogeologic units in the Northern Atlantic Coastal Plain aquifer system from Long Island, New York, to North Carolina

    USGS Publications Warehouse

    Pope, Jason P.; Andreasen, David C.; Mcfarland, E. Randolph; Watt, Martha K.

    2016-08-31

    Digital geospatial datasets of the extents and top elevations of the regional hydrogeologic units of the Northern Atlantic Coastal Plain aquifer system from Long Island, New York, to northeastern North Carolina were developed to provide an updated hydrogeologic framework to support analysis of groundwater resources. The 19 regional hydrogeologic units were delineated by elevation grids and extent polygons for 20 layers: the land and bathymetric surface at the top of the unconfined surficial aquifer, the upper surfaces of 9 confined aquifers and 9 confining units, and the bedrock surface that defines the base of all Northern Atlantic Coastal Plain sediments. The delineation of the regional hydrogeologic units relied on the interpretive work from source reports for New York, New Jersey, Delaware and Maryland, Virginia, and North Carolina rather than from re-analysis of fundamental hydrogeologic data. This model of regional hydrogeologic unit geometries represents interpolation, extrapolation, and generalization of the earlier interpretive work. Regional units were constructed from available digital data layers from the source studies in order to extend units consistently across political boundaries and approximate units in offshore areas.Though many of the Northern Atlantic Coastal Plain hydrogeologic units may extend eastward as far as the edge of the Atlantic Continental Shelf, the modeled boundaries of all regional hydrogeologic units in this study were clipped to an area approximately defined by the furthest offshore extent of fresh to brackish water in any part of the aquifer system, as indicated by chloride concentrations of 10,000 milligrams per liter. Elevations and extents of units that do not exist onshore in Long Island, New York, were not included north of New Jersey. Hydrogeologic units in North Carolina were included primarily to provide continuity across the Virginia-North Carolina State boundary, which was important for defining the southern edge of

  9. Spatio-temporal analysis of gyres in oriented lakes on the Arctic Coastal Plain of northern Alaska based on remotely sensed images

    USGS Publications Warehouse

    Zhan, Shengan; Beck, Richard A.; Hinkel, Kenneth M.; Liu, Hongxing; Jones, Benjamin M.

    2014-01-01

    The formation of oriented thermokarst lakes on the Arctic Coastal Plain of northern Alaska has been the subject of debate for more than half a century. The striking elongation of the lakes perpendicular to the prevailing wind direction has led to the development of a preferred wind-generated gyre hypothesis, while other hypotheses include a combination of sun angle, topographic aspect, and/or antecedent conditions. A spatio-temporal analysis of oriented thermokarst lake gyres with recent (Landsat 8) and historical (Landsat 4, 5, 7 and ASTER) satellite imagery of the Arctic Coastal Plain of northern Alaska indicates that wind-generated gyres are both frequent and regionally extensive. Gyres are most common in lakes located near the Arctic coast after several days of sustained winds from a single direction, typically the northeast, and decrease in number landward with decreasing wind energy. This analysis indicates that the conditions necessary for the Carson and Hussey (1962) wind-generated gyre for oriented thermokarst lake formation are common temporally and regionally and correspond spatially with the geographic distribution of oriented lakes on the Arctic Coastal Plain. Given an increase in the ice-free season for lakes as well as strengthening of the wind regime, the frequency and distribution of lake gyres may increase. This increase has implications for changes in northern high latitude aquatic ecosystems, particularly if wind-generated gyres promote permafrost degradation and thermokarst lake expansion.

  10. Regional ground-water discharge to large streams in the upper coastal plain of South Carolina and parts of North Carolina and Georgia

    USGS Publications Warehouse

    Aucott, W.R.; Meadows, R.S.; Patterson, G.G.

    1987-01-01

    Base flow was computed to estimate discharge from regional aquifers for six large streams in the upper Coastal Plain of South Carolina and parts of North Carolina and Georgia. Aquifers that sustain the base flow of both large and small streams are stratified into shallow and deep flow systems. Base-flow during dry conditions on main stems of large streams was assumed to be the discharge from the deep groundwater flow system. Six streams were analyzed: the Savannah, South and North Fork Edisto, Lynches, Pee Dee, and the Luber Rivers. Stream reaches in the Upper Coastal Plain were studied because of the relatively large aquifer discharge in these areas in comparison to the lower Coastal Plain. Estimates of discharge from the deep groundwater flow system to the six large streams averaged 1.8 cu ft/sec/mi of stream and 0.11 cu ft/sec/sq mi of surface drainage area. The estimates were made by subtracting all tributary inflows from the discharge gain between two gaging stations on a large stream during an extreme low-flow period. These estimates pertain only to flow in the deep groundwater flow system. Shallow flow systems and total base flow are > flow in the deep system. (USGS)

  11. Comparison of Historical and Recent Shoreline Change Rates to Shoreface and Lower Coastal Plain Geomorphology: Geologic Framework Influences on Shoreline Evolution in South Carolina

    NASA Astrophysics Data System (ADS)

    Harris, M. S.; Wright, E. E.; Dufrene, T. A.; Gayes, P. T.; Katuna, M. P.; Putney, T. R.; Bush, D. M.; Schwab, W. C.

    2002-12-01

    The lower Coastal Plain and inner Continental Shelf of the United States East Coast vary coherently in both pre-Holocene and modern morphology, in long-term trends of coastal change, and in respect to critical areas of beach erosion. As a portion of the USGS-SC Sea Grant Consortium coastal erosion program, this study presents a comparison of historical to recent shoreline change rates with the geomorphology of the lower Coastal Plain and inner portions of the Continental Shelf of South Carolina. Shoreline change trends of re-digitized historical data of Anders et al. (1990) and recent aerial photographs were analyzed using ARC/INFO, ArcGIS and scripts modified from the original DSAS program (Thieler and Danforth, 1994) and the currently active National Shoreline Change Program (US Geological Survey, St. Petersburg, FL). Lower Coastal Plain and coastal geomorphology data come from digital USGS topographic data, Horry County department of engineering (approximately 0.4 m vertical resolution), and NOAA LIDAR data for the immediate coastline. NOAA and USGS processed bathymetry were merged with these data for South Carolina to produce a seamless hypsographic data layer for these physiographic regions. Sidescan sonar surveys over the past eight years in South Carolina provide additional shoreface data for the Charleston and Grand Strand (Myrtle Beach) areas of South Carolina. As expected, the highest and most consistent variances in shoreline change trends are associated with inlets, small swashes, washover barriers, and beach renourishment projects. However, critical trends in coastal change in regions outside those typically associated with hot spots of erosion point to other, non-hydrodynamic influences on the coastal system. These influences may include truncation of modern dune ridges, of low-elevation Pleistocene terraces and beach faces, of highly-varied stratigraphic units, and of indurated near-surface strata, which all have direct influence on long-term average

  12. Late Cretaceous to Miocene sea-level estimates from the New Jersey and Delaware coastal plain coreholes: An error analysis

    USGS Publications Warehouse

    Kominz, M.A.; Browning, J.V.; Miller, K.G.; Sugarman, P.J.; Mizintseva, S.; Scotese, C.R.

    2008-01-01

    Sea level has been estimated for the last 108 million years through backstripping of corehole data from the New Jersey and Delaware Coastal Plains. Inherent errors due to this method of calculating sea level are discussed, including uncertainties in ages, depth of deposition and the model used for tectonic subsidence. Problems arising from the two-dimensional aspects of subsidence and response to sediment loads are also addressed. The rates and magnitudes of sea-level change are consistent with at least ephemeral ice sheets throughout the studied interval. Million-year sea-level cycles are, for the most part, consistent within the study area suggesting that they may be eustatic in origin. This conclusion is corroborated by correlation between sequence boundaries and unconformities in New Zealand. The resulting long-term curve suggests that sea level ranged from about 75-110 m in the Late Cretaceous, reached a maximum of about 150 m in the Early Eocene and fell to zero in the Miocene. The Late Cretaceous long-term (107 years) magnitude is about 100-150 m less than sea level predicted from ocean volume. This discrepancy can be reconciled by assuming that dynamic topography in New Jersey was driven by North America overriding the subducted Farallon plate. However, geodynamic models of this effect do not resolve the problem in that they require Eocene sea level to be significantly higher in the New Jersey region than the global average. ?? 2008 The Authors. Journal compilation ?? 2008 Blackwell Publishing.

  13. Sedimentation patterns across a Coastal Plain floodplain: The importance of hydrogeomorphic influences and cross-floodplain connectivity

    NASA Astrophysics Data System (ADS)

    Kaase, Christopher T.; Kupfer, John A.

    2016-09-01

    The floodplains of large Coastal Plain rivers in the southeastern U.S. are important long-term storage sites for alluvial sediment and nutrients. Yet considerable uncertainty surrounds sediment dynamics on many large river floodplains and, in particular, the local scale factors that affect the flux of sediment and nutrients from rivers onto their floodplains and their subsequent deposition. This research quantifies short-term rates of sediment deposition from 2012 to 2014 on floodplain sites at Congaree National Park using feldspar pads. Sediment deposition rates ranged from 0.1 to 15.6 cm (median = 1.46 cm) and were closely associated with inundation frequency and geomorphic position. Cross-floodplain distributary channels served as particularly important conduits for moving sediment onto the floodplain. Physical and chemical analyses of soil samples demonstrated that the most flood-exposed sites had higher major nutrient and micronutrient levels (especially of phosphorus) and more diverse nutrient compositions. This research advances current understandings of lateral floodplain connectivity by demonstrating the complex effects of regional hydrology and local floodplain environmental characteristics on the supply of sediment and nutrients.

  14. Surface-water quality in agricultural watersheds of the North Carolina Coastal Plain associated with concentrated animal feeding operations

    USGS Publications Warehouse

    Harden, Stephen L.

    2015-01-01

    A classification tree model was developed to examine relations of watershed environmental attributes among the study sites with and without CAFO manure effects. Model results indicated that variations in swine barn density, percentage of wetlands, and total acres available for applying swine-waste manures had an important influence on those watersheds where CAFO effects on water quality were either evident or mitigated. Measurable effects of CAFO waste manures on stream water quality were most evident in those SW and SP watersheds having lower percentages of wetlands combined with higher swine barn densities and (or) higher total acres available for applying waste manure at the swine CAFOs. Stream water quality was similar to background agricultural conditions in SW and SP watersheds with lower swine barn densities coupled with higher percentages of wetlands or lower acres available for swine manure applications. The model provides a useful tool for exploring and identifying similar, unmonitored watersheds in the North Carolina Coastal Plain with potential CAFO manure influences on water quality that might warrant further examination.

  15. Bacteria in deep coastal plain sediments of Maryland: a possible source of CO/sub 2/ to ground water

    SciTech Connect

    Chapelle, F.H.; Zelibor, J.L. Jr.; Grimes, D.J.; Knobel, L.L.

    1987-01-01

    Nineteen cores of unconsolidated Coastal Plain sediments obtained from depths of 14 to 182 m below land surface near Waldorf, Maryland, were collected and examined for metabolically active bacteria. The age of the sediments cored range from Miocene to Early Cretaceous. Acridine orange direct counts of total (viable and nonviable) bacteria in core subsamples ranged from 10/sup 8/ to 10/sup 4/ bacteria/g of dry sediment. Direct counts of viable bacteria ranged from 10/sup 6/ to 10/sup 3/ bacteria/g of dry sediment. Three cores contained viable methanogenic bacteria, and seven cores contained viable sulfate-reducing bacteria. The observed presence of bacteria in these sediments suggest that hetrotrophic bacterial metabolism, with lignitic organic material as the primary substrate, is a plausible source of CO/sub 2/ to ground water. However, the possibility that abiotic processes also produce CO/sub 2/ cannot be rules out. Estimated rates of CO/sub 2/ production in the noncalcareous Magothy/Upper Patapsco and Lower Patapsco aquifers based on mass balance of dissolved inorganic carbon, ground water flow rates, and flow path segment lengths are in the range 10/sup -3/ to 10/sup -5/ mmol L/sup -1/ yr/sup -1/. Isotope balance calculations suggest that aquifer-generated CO/sub 2/ is much heavier isotopically ( approx. - 10 to + 5 per mil) than lignite ( approx. - 24 per mil) present in these sediments. This may reflect isotopic fractionation during methanogenesis and possibly other bacterially mediated processes.

  16. Quaternary sea level high-stand deposits of the southeast U.S. Atlantic Coastal Plain: Age, distribution, and implications.

    NASA Astrophysics Data System (ADS)

    Poirier, R. K.; Cronin, T. M.; Ghaleb, B.; Portell, R.; Hillaire-Marcel, C.; Wehmiller, J. F.; Thompson, W. G.; Oches, E. A.; Willard, D. A.; Katz, M. E.

    2015-12-01

    Emerged Quaternary paleo-shorelines and marine deposits provide a more direct way to reconstruct and analyze sea-level variability than methods using oxygen isotope analyses of deep ocean benthic foraminifera. New Uranium-series dates on fossil corals (primarily Astrangia spp. and Septastrea spp.) combined with previously published dates have allowed us to constrain the age, elevation, and geographical distribution of marine sediments deposited in the United States Atlantic Coastal Plain (ACP) from Virginia to Florida during periods of past high relative sea level (SL). We present new dates from deposits (VA/NC: Tabb/Norfolk, Nassawadox, & Omar Formations; SC: Wando, Socastee, & Canepatch Formations; FL: Anastasia, Ft. Thompson, & Bermont Formations) representing interglacial high-stands during Marine Isotope Stages (MIS) 5, 7, 9, and 11. In addition, we incorporate stratigraphic, marine micropaleontologic, and palynologic records with our SL chronology to reconstruct a more complete history of middle-to-late Pleistocene interglacial climates of the ACP. Ultimately, these results will test modeled sea-level fingerprint studies based on various melting scenarios of the Greenland and/or Antarctic ice sheets.

  17. The genus Krithe (Ostracoda) from the Campanian and Maastrichtian (Upper Cretaceous) of the northern US Gulf Coastal Plain

    USGS Publications Warehouse

    Puckett, T.M.

    1997-01-01

    The ostracode genus Krithe is one of the most common genera in the Upper Cretaceous (late Santonian to Maastrichtian) deposits of the northern Gulf Coastal Plain of North America. Although it is never abundant, the genus occurs in sediments that were deposited under a wide range of palaeoenvironments, including nearshore sandy marls to offshore, nearly pure, chalk. The taxonomy of this taxon has been problematical, and what is herein considered to be a single species, K. cushmani, has been referred to in the literature under five different names. Two morphotypes were observed: relatively large individuals with 'mushroom'-shaped vestibules collected from chalk, and smaller individuals with pocket-shaped vestibules collected from nearshore deposits. Species of Krithe have been hypothesized to be useful in estimating dissolved oxygen concentration in ancient ocean floors, based on details of their morphology. Whereas the relationship between size and environment corroborates with previous predictions (larger individuals live in deeper water), the morphology of the vestibules contradicts predictions (the larger vestibules occur in the nearshore deposits and the smaller, more constricted vestibules occur in the chalk). A causal relationship between environment and morphology is discussed.

  18. Predicting the distribution of Upper Cretaceous aquifers using sea-level analysis and regional paleogeography, Alabama coastal plain

    SciTech Connect

    King, D.T. Jr.; Skotnicki, M.C. )

    1991-03-01

    In the inner coastal plain of Alabama, Upper Cretaceous (i.e., Santonian-Maastrichtian) stratigraphic units containing key aquifers dip south at 7m/km; the aquifers consist mainly of porous and permeable barrier-island facies (including upper-shoreface and tidal-pass sands), barrier-related sand facies (including tidal deltas and lagoonal and marine tempestite beds), and shallow-marine sand facies (including offshore bars and conglomerate sandy turbidite tongues). Confining aquitard and aquiclude facies include lagoonal silty clays, shallow-marine glauconitic clays, clayey marls, and marine chalky marls. The gross geometry, thickness, and lateral and vertical distribution of aquifer sands in both the shallow-subsurface and outcrop (i.e., recharge) area is predictable based on regional paleogeographic reconstructions and the regional Late Cretaceous relative sea-level curve. At a local scale, facies maps and shallow-subsurface correlations provide essential data for aquifer exploration and recharge-area protection. For example, in the Eutaw Formation, barrier-island and barrier-related facies developed along a curved east-west striking shoreline; aquifers include shoreline facies, tempestite beds, and turbidite sands. In the younger, northwest-striking Blufftown-Cusseta and Ripley-Providence systems, aquifers are barrier-island and barrier-related (especially tidal-delta) facies.

  19. Ground water flow analysis of a mid-Atlantic outer coastal plain watershed, Virginia, U.S.A.

    PubMed

    Robinson, Michael A; Reay, William G

    2002-01-01

    Models for ground water flow (MODFLOW) and particle tracking (MODPATH) were used to determine ground water flow patterns, principal ground water discharge and recharge zones, and estimates of ground water travel times in an unconfined ground water system of an outer coastal plain watershed on the Delmarva Peninsula, Virginia. By coupling recharge and discharge zones within the watershed, flowpath analysis can provide a method to locate and implement specific management strategies within a watershed to reduce ground water nitrogen loading to surface water. A monitoring well network was installed in Eyreville Creek watershed, a first-order creek, to determine hydraulic conductivities and spatial and temporal variations in hydraulic heads for use in model calibration. Ground water flow patterns indicated the convergence of flow along the four surface water features of the watershed; primary discharge areas were in the nontidal portions of the watershed. Ground water recharge zones corresponded to the surface water features with minimal development of a regional ground water system. Predicted ground water velocities varied between < 0.01 to 0.24 m/day, with elevated values associated with discharge areas and areas of convergence along surface water features. Some ground water residence times exceeded 100 years, although average residence times ranged between 16 and 21 years; approximately 95% of the ground water resource would reflect land use activities within the last 50 years.

  20. Cold-climate slope deposits and landscape modifications of the Mid-Atlantic Coastal Plain, Eastern USA

    USGS Publications Warehouse

    Newell, W.L.; Dejong, B.D.

    2011-01-01

    The effects of Pleistocene cold-climate geomorphology are distributed across the weathered and eroded Mid-Atlantic Coastal Plain uplands from the Wisconsinan terminal moraine south to Tidewater Virginia. Cold-climate deposits and landscape modifications are superimposed on antecedent landscapes of old, weathered Neogene upland gravels and Pleistocene marine terraces that had been built during warm periods and sea-level highstands. In New Jersey, sequences of surficial deposits define a long history of repeating climate change events. To the south across the Delmarva Peninsula and southern Maryland, most antecedent topography has been obscured by Late Pleistocene surficial deposits. These are spatially variable and are collectively described as a cold-climate alloformation. The cold-climate alloformation includes time-transgressive details of climate deterioration from at least marine isotope stage (MIS) 4 through the end of MIS 2. Some deposits and landforms within the alloformation may be as young as the Younger Dryas. Southwards along the trend of the Potomac River, these deposits and their climatic affinities become diffused. In Virginia, a continuum of erosion and surficial deposits appears to be the product of ‘normal’ temperate, climate-forced processes. The cold-climate alloformation and more temperate deposits in Virginia are being partly covered by Holocene alluvium and bay mud.

  1. Estimating net drawdown resulting from episodic withdrawals at six well fields in the coastal plain physiographic province of Virginia

    USGS Publications Warehouse

    Focazio, M.J.; Speiran, G.K.

    1993-01-01

    The groundwater-flow system of the Virginia Coastal Plain consists of areally extensive and interconnected aquifers. Large, regionally coalescing cones of depression that are caused by large withdrawals of water are found in these aquifers. Local groundwater systems are affected by regional pumping, because of the interactions within the system of aquifers. Accordingly, these local systems are affected by regional groundwater flow and by spatial and temporal differences in withdrawals by various users. A geographic- information system was used to refine a regional groundwater-flow model around selected withdrawal centers. A method was developed in which drawdown maps that were simulated by the regional groundwater-flow model and the principle of superposition could be used to estimate drawdown at local sites. The method was applied to create drawdown maps in the Brightseat/Upper Potomac Aquifer for periods of 3, 6, 9, and 12 months for Chesapeake, Newport News, Norfolk, Portsmouth, Suffolk, and Virginia Beach, Virginia. Withdrawal rates were supplied by the individual localities and remained constant for each simulation period. This provides an efficient method by which the individual local groundwater users can determine the amount of drawdown produced by their wells in a groundwater system that is a water source for multiple users and that is affected by regional-flow systems.

  2. Effect of eustatic sea-level changes on saltwater-freshwater relations in the Northern Atlantic Coastal Plain

    USGS Publications Warehouse

    Meisler, Harold; Leahy, P. Patrick; Knobel, LeRoy L.

    1984-01-01

    A finite-difference computer model was used to analyze the effect of eustatic sea-level changes on the development of the transition zone between fresh ground water and underlying saltwater in the northern Atlantic Coastal Plain. The model simulates, in cross section, the sedimentary wedge from the Delaware River estuary in New Jersey to the Continental Slope. Simulated steady-state freshwater flow is separated from static saltwater by a sharp interface. The model was used to test the sensitivity of the simulated interface position to anisotropy as well as to sea-level elevation. Increasing anisotropy causes the interface to be shallower and extend farther offshore. Lowering sea level causes the interface to be deeper and to extend farther offshore. Simulations using hydraulic conductivities based on available data suggest that the transition zone is not in equilibrium with present sea level. The position of the transition zone probably reflects a long-term average sea level of between 50 and 100 ft below present sea level. The cyclic movement of salty ground water in response to sea-level fluctuations during the Quaternary and Late Tertiary caused the saltwater to mix with freshwater, thus producing a broad transition zone. The freshwater is predominantly sodium bicarbonate in character. The saltwater, from New Jersey to Virginia, probably is a sodium calcium chloride brine. In North Carolina, it is primarily seawater.

  3. [The pollination of Krameria bahiana B.B. Simpson by bees in the Coastal Sand Plains of Bahia, Brazil].

    PubMed

    Gimenes, Miriam; Lobão, Cybelle da S

    2006-01-01

    The flowers of K. bahiana mainly produce oil as floral resource for their visitors. Oil collecting bees usually show morphological and behavioral adaptation for their collection. This study focused on the analysis of interactions between the flowers of K. bahiana and their visiting bees, aiming for the efficiency of the pollination, in an area of the Coastal Sand Plains of Bahia State, Brazil. From February/2001 to February/2002 and from May to October/2002 observations were accomplished about the phenology and morphology of the plants and the floral visitors' behavior. The flowers of the inflorescences are zigomorphic, small sized, pink and present a pair of petals modified in epithelial elaiophores, which are responsible for the production of oil. These flowers were visited especially by bees of the genus Centris: C. leprieuri Spinola, C. tarsata Smith, C. trigonoides Lepeletier and C. pulchra Moure, Oliveira & Viana. The bees collected only oil in the flowers, by scratching the elaiophores and then transferring it to scopa located on the tibia and basitarsus of the hind legs. During those actions, the bees often contact the reproductive structures of the flowers, resulting in pollination. C. leprieuri was the most frequent bee during this study, thus considered the effective pollinator. Megachile dentipes Vachal also visited the flowers of K. bahiana, collecting only pollen. However, these bees were considered sporadic pollinators because they were not frequent in the flowers of K. bahiana in the months of observation. PMID:17061790

  4. Groundwater and stream E. coli concentrations in coastal plain watersheds served by onsite wastewater and a municipal sewer treatment system.

    PubMed

    Humphrey, Charles; Finley, Algernon; O'Driscoll, Michael; Manda, Alex; Iverson, Guy

    2015-01-01

    The goal of this study was to determine if onsite wastewater treatment systems (OWS) were influencing groundwater and surface water Escherichia coli concentrations in a coastal plain watershed. Piezometers for groundwater monitoring were installed at four residences served by OWS and five residences served by a municipal wastewater treatment system (MWS). The residences were located in two different, but nearby (<3 km), watersheds. Effluent from the four septic tanks, groundwater from piezometers, and the streams draining the OWS and MWS watersheds were sampled on five dates between September 2011 and May 2012. Groundwater E. coli concentrations and specific conductivity were elevated within the flow path of the OWS and near the stream, relative to other groundwater sampling locations in the two watersheds. Groundwater discharge in the OWS watershed could be a contributor of E. coli to the stream because E. coli concentrations in groundwater at the stream bank and in the stream were similar. Stream E. coli concentrations were higher for the OWS in relation to MWS watersheds on each sampling date. Water quality could be improved by ensuring OWS are installed and operated to maintain adequate separation distances to water resources.

  5. A field test of the centrifugal community organization model using psammophilic gerbils in Israel's southern coastal plain

    USGS Publications Warehouse

    Wasserberg, G.; Kotler, B.P.; Morris, D.W.; Abramsky, Z.

    2007-01-01

    Background: An optimal habitat selection model called centrifugal community organization (CCO) predicts that species, although they have the same primary habitat, may co-exist owing to their ability to use different secondary habitats. Goal: Test the predictions of CCO with field experiments. Species: The Egyptian sand gerbil (40 g), Gerbillus pyramidum, and Allenby's gerbil (25 g), G. andersoni allenbyi. Site: Ashdod sand dunes in the southern coastal plain of Israel. Three sandy habitats are present: shifting, semi-stabilized, and stabilized sand. Gerbils occupied all three habitats. Methods: We surveyed rodent abundance, activity levels, and foraging behaviour while experimentally removing G. pyramidum. Results: Three predictions of the CCO model were supported. Both species did best in the semi-stabilized habitat. However, they differed in their secondary habitats. Gerbillus pyramidum preferred the shifting sand habitat, whereas G. a. allenbyi preferred the stabilized habitat. Habitat selection by both species depended on density. However, in contrast to CCO, G. pyramidum dominated the core habitat and excluded G. a. allenbyi. We term this variant of CCO, 'asymmetric CCO'. Conclusions: The fundamental feature of CCO appears valid: co-existence may result not because of what each competing species does best, but because of what they do as a back-up. But in contrast to the prediction of the original CCO model, all dynamic traces of interaction can vanish if the system includes interference competition. ?? 2007 Gideon Wasserberg.

  6. Groundwater and stream E. coli concentrations in coastal plain watersheds served by onsite wastewater and a municipal sewer treatment system.

    PubMed

    Humphrey, Charles; Finley, Algernon; O'Driscoll, Michael; Manda, Alex; Iverson, Guy

    2015-01-01

    The goal of this study was to determine if onsite wastewater treatment systems (OWS) were influencing groundwater and surface water Escherichia coli concentrations in a coastal plain watershed. Piezometers for groundwater monitoring were installed at four residences served by OWS and five residences served by a municipal wastewater treatment system (MWS). The residences were located in two different, but nearby (<3 km), watersheds. Effluent from the four septic tanks, groundwater from piezometers, and the streams draining the OWS and MWS watersheds were sampled on five dates between September 2011 and May 2012. Groundwater E. coli concentrations and specific conductivity were elevated within the flow path of the OWS and near the stream, relative to other groundwater sampling locations in the two watersheds. Groundwater discharge in the OWS watershed could be a contributor of E. coli to the stream because E. coli concentrations in groundwater at the stream bank and in the stream were similar. Stream E. coli concentrations were higher for the OWS in relation to MWS watersheds on each sampling date. Water quality could be improved by ensuring OWS are installed and operated to maintain adequate separation distances to water resources. PMID:26540548

  7. The effect of global warming scenarios on soybean and peanut yields in the Coastal Plain region of Georgia

    SciTech Connect

    Laitta, M.T.; Huebner, N.J.

    1996-09-01

    This study is an evaluation of peanut and soybean yield in the Coastal Plain of Georgia as a function of seasonal water deficit scenarios. An analytical model of the Thornthwaite water balance model, based on historical temperature and precipitation data, is used to evaluate the probable response of crop productivity to climate changes in selected counties in South Georgia. The input of temperature and precipitation values for each site is based on the results of three general circulation models (GCM), which were regionally tailored to the Southeastern United States. A regression analysis was preformed to establish a numerical relationship between historical yield and moisture deficits. This model, in association with projected GCM model deficits, was used to predict future crop yields. Our results showed that given all GCM models evaluated, deficit periods for the selected sites will increase both the intensity and duration droughts in the southeastern U.S. Of the two crops analyzed, it was found that soybeans showed a higher sensitivity to moisture deficits than did peanuts.

  8. Climate driven changes in hydrology, nutrient cycling, and food web dynamics in surface waters of the Arctic Coastal Plain, Alaska

    NASA Astrophysics Data System (ADS)

    Koch, J. C.; Wipfli, M.; Schmutz, J.; Gurney, K.

    2011-12-01

    Arctic ecosystems are changing rapidly as a result of a warming climate. While many areas of the arctic are expected to dry as a result of warming, the Arctic Coastal Plain (ACP) of Alaska, which extends from the Brooks Range north to the Beaufort Sea will likely become wetter, because subsurface hydrologic fluxes are constrained by thick, continuous permafrost. This landscape is characterized by large, oriented lakes and many smaller ponds that form in the low centers and troughs/edges of frost polygons. This region provides important breeding habitat for many migratory birds including loons, arctic terns, eiders, shorebirds, and white-fronted geese, among others. Increased hydrologic fluxes may provide a bottom-up control on the success of these species by altering the availability of food resources including invertebrates and fish. This work aimed to 1) characterize surface water fluxes and nutrient availability in the small streams and lake types of two study regions in the ACP, 2) predict how increased hydrological fluxes will affect the lakes, streams, and water chemistry, and 3) use nutrient additions to simulate likely changes in lake chemistry and invertebrate availability. Initial observations suggest that increasing wetland areas and availability of nutrients will result in increased invertebrate abundance, while the potential for drainage and terrestrialization of larger lakes may reduce fish abundance and overwintering habitat. These changes will likely have positive implications for insectivores and negative implications for piscivorous waterfowl.

  9. Survival dynamics of fecal bacteria in ponds in agricultural watersheds of the Piedmont and Coastal Plain of Georgia.

    PubMed

    Jenkins, Michael B; Endale, Dinku M; Fisher, Dwight S; Adams, M Paige; Lowrance, Richard; Newton, G Larry; Vellidis, George

    2012-01-01

    Animal agriculture in watersheds produces manure bacteria that may contaminate surface waters and put public health at risk. We measured fecal indicator bacteria (commensal Escherichia coli and fecal enterococci) and manure pathogens (Salmonella and E. coli 0157:H7), and physical-chemical parameters in pond inflow, within pond, pond outflow, and pond sediments in three ponds in agricultural watersheds. Bishop Pond with perennial inflow and outflow is located in the Piedmont, and Ponds A and C with ephemeral inflow and outflow in the Coastal Plain of Georgia. Bromide and chloride tracer experiments at Bishop Pond reflected a residence time much greater than that estimated by two models, and indicated that complete mixing within Bishop Pond was never obtained. The long residence time meant that fecal bacteria were exposed to solar UV-radiation and microbial predation. At Bishop Pond outflow concentrations of fecal indicator bacteria were significantly less than inflow concentrations; such was not observed at Ponds A and C. Both Salmonella and E. coli 0157:H7 were measured when concomitant concentrations of commensal E. coli were below the criterion for surface water impairment indicating problems with the effectiveness of indicator organisms. Bishop Pond improved down stream water quality; whereas, Ponds A and C with ephemeral inflow and outflow and possibly greater nutrient concentrations within the two ponds appeared to be less effective in improving down stream water quality.

  10. Impacts of prescribed fire on Pinus rigida Mill. in upland forests of the Atlantic Coastal Plain.

    PubMed

    Carlo, Nicholas J; Renninger, Heidi J; Clark, Kenneth L; Schäfer, Karina V R

    2016-08-01

    A comparative analysis of the impacts of prescribed fire on three upland forest stands in the Northeastern Atlantic Plain, NJ, USA, was conducted. Effects of prescribed fire on water use and gas exchange of overstory pines were estimated via sap-flux rates and photosynthetic measurements on Pinus rigida Mill. Each study site had two sap-flux plots, one experiencing prescribed fire and one control (unburned) plot for comparison before and after the fire. We found that photosynthetic capacity in terms of Rubisco-limited carboxylation rate and intrinsic water-use efficiency was unaffected, while light compensation point and dark respiration rate were significantly lower in the burned vs control plots post-fire. Furthermore, quantum yield in pines in the pine-dominated stands was less affected than pines in the mixed oak/pine stand, as there was an increase in quantum yield in the oak/pine stand post-fire compared with the control (unburned) plot. We attribute this to an effect of forest type but not fire per se. Average daily sap-flux rates of the pine trees increased compared with control (unburned) plots in pine-dominated stands and decreased in the oak/pine stand compared with control (unburned) plots, potentially due to differences in fuel consumption and pre-fire sap-flux rates. Finally, when reference canopy stomatal conductance was analyzed, pines in the pine-dominated stands were more sensitive to changes in vapor pressure deficit (VPD), while stomatal responses of pines in the oak/pine stand were less affected by VPD. Therefore, prescribed fire affects physiological functioning and water use of pines, but the effects may be modulated by forest stand type and fuel consumption pattern, which suggests that these factors may need to be taken into account for forest management in fire-dominated systems. PMID:27259637

  11. Stratigraphy and depositional environments of Vicksburgian Oligocene of northern Gulf Coastal Plain

    SciTech Connect

    Coleman, J.L. Jr.

    1983-03-01

    The Vicksburg Group (Oligocene) is a predominantly carbonate unit that extends in a narrow belt from Rosefield, Louisiana, to western Florida. East of the LaSalle arch (eastern Louisiana) the carbonates of the Vicksburg Group are continental shelf in origin and display a sedimentary strike of approximately eastwest. The carbonate formations of the Vicksburg Group are demonstrated to be facies of one another and to constitute a single sedimentary cycle. The outcrop belt strikes west-northwest across the sedimentary strike displaying changes in the lithofacies of the group. The Byram Formation is redefined to include the silty sands and wackestones of a regressive carbonate shelf/destructional bank facies. The Glendon Formation is restricted to include only the skeletal grainstones and coarse sands of a carbonate shoal/shoreline. The Marianna Formation includes mudstones of an algal mud shelf bottom and silty sands of a back-bank facies. The Mint Spring Formation consists of silty sands of a destructional delta environment and includes those glauconite sands that overlie the prodelta clays of the Forest Hill Formation. The Rosefield Formation is probably a chenier plain silty clay with a coquina beach zone of fossils common to the Byram Formation. Penecontemporaneous or post-Vicksburg erosion on the crest of the Wiggins uplift apparently restricted or removed possible Vicksburgian coral-algal reef or nummulitic bank sediments. Limited subsurface data show that a nummulitic bank did develop on the north flank of the uplift. This bank migrated northward as the Marianna back-bank area shoaled and produced the Nummulites-Lepidocyclina grainstone/sand of the Glendon Formation at its type locality.

  12. Classification of freshwater ice conditions on the Alaskan Arctic Coastal Plain using ground penetrating radar and TerraSAR-X satellite data

    USGS Publications Warehouse

    Jones, Benjamin M.; Gusmeroli, Alessio; Arp, Christopher D.; Strozzi, Tazio; Grosse, Guido; Gaglioti, Benjamin V.; Whitman, Matthew S.

    2013-01-01

    Arctic freshwater ecosystems have responded rapidly to climatic changes over the last half century. Lakes and rivers are experiencing a thinning of the seasonal ice cover, which may increase potential over-wintering freshwater habitat, winter water supply for industrial withdrawal, and permafrost degradation. Here, we combined the use of ground penetrating radar (GPR) and high-resolution (HR) spotlight TerraSAR-X (TSX) satellite data (1.25 m resolution) to identify and characterize floating ice and grounded ice conditions in lakes, ponds, beaded stream pools, and an alluvial river channel. Classified ice conditions from the GPR and the TSX data showed excellent agreement: 90.6% for a predominantly floating ice lake, 99.7% for a grounded ice lake, 79.0% for a beaded stream course, and 92.1% for the alluvial river channel. A GIS-based analysis of 890 surface water features larger than 0.01 ha showed that 42% of the total surface water area potentially provided over-wintering habitat during the 2012/2013 winter. Lakes accounted for 89% of this area, whereas the alluvial river channel accounted for 10% and ponds and beaded stream pools each accounted for <1%. Identification of smaller landscape features such as beaded stream pools may be important because of their distribution and role in connecting other water bodies on the landscape. These findings advance techniques for detecting and knowledge associated with potential winter habitat distribution for fish and invertebrates at the local scale in a region of the Arctic with increasing stressors related to climate and land use change.

  13. Atlantic Flyway Review: Piedmont?Coastal Plain, Region IV, Fall 2001

    USGS Publications Warehouse

    Robbins, C.S.; Dawson, D.K.

    2002-01-01

    Ten banding stations, six inland, four coastal, monitored the fall songbird migration from Maryland to Florida. Comparing the eight stations that were operated in both 2000 and 2001, net-hours of effort declined 5.3% from 60,649 to 57,405, but birds per 100 net-hours increased from 40.1 to 46.6. Myrtle Warblers were especially abundant this year, while numbers of catbirds declined. At my Laurel station, I compared my fall catch for the first five years (1973-77) with that for the past five years (1997-2001) and found the totals nearly identical (2175 and 2169), but it took nearly three times the number of net-hours to achieve the same total in the current period. A migrating Gray-cheeked Thrush, in spite of being captured 10 times in 17 days, increased its weight from 31.0 g to a record 51.7 g in 13 days.

  14. Effects of salinity on freshwater fishes in coastal plain drainages in the southeastern U.S.

    USGS Publications Warehouse

    Peterson, Mark S.; Meador, Michael R.

    1994-01-01

    This review focuses on the influence of salinity on freshwater fishes in coastal rivers and estuaries of the southeastern U.S. Influences of salinity on freshwater fish species can be explained partly through responses evidenced by behavior, physiology, growth, reproduction, and food habits during all aspects of life history. Factors influencing the rate of salinity change affect the community structure and dynamics of freshwater fishes in brackish environments. Our understanding of the relation between salinity and the life history of freshwater fishes is limited because little ecological research has been conducted in low-salinity habitats that we consider an “interface” between freshwater streams and the estuary proper. Much of the available data are descriptive in nature and describe best general patterns, but more specific studies are required to better determine the influence of salinity on freshwater fishes. Improved understanding of the influence of human-induced changes on the productivity and viability of these important systems will require a new research focus.

  15. Geophysical investigations of the crust and mantle beneath Texas' Gulf Coastal Plain

    NASA Astrophysics Data System (ADS)

    Gurrola, H.; Pulliam, J.; Knuppel, M.; Agrawal, M.

    2015-12-01

    EarthScope's Transportable Array (TA) and a dense broadband profile (X4) that coincided with TA deployments in Texas formed the basis for higher resolution geophysical investigations than previously possible in the Gulf Coast Plain (GCP). X4 is a 300-km-long array of 26 broadband seismic stations deployed from Matagorda Island across the GCP, ending near the center of the Llano uplift (LU). The study found an 80-100 km wide "lithosphere-asthenosphere transition zone" (LATZ). While a negative Sp phase at ~110 km depth could be interpreted as a shallow LAB, several negative Sp phases were also found in the 110-180 km depth interval and this set of negative Sp phases is bounded by a positive Sp phase at 180-200 km depth that is semi-continuous across the length of the array. We interpret the depth interval's negative anomalies to be the results of partial melt and shearing in a softened or underdeveloped lithosphere, thus the term LATZ. The GCP was also found to have large SKS splitting delay times, which we believe is due to seismic anisotropy in the LATZ (the zone of assumed shearing). Body wave tomography found slightly high Vp but unusually low Vs beneath the GCP; Vs is more sensitive to partial melt and anisotropy than Vp, further supporting the LATZ hypothesis. Ps and Sp Moho phases are observed at ~35 km beneath the LU but both Sp and Ps RFs fail to image a Moho beneath the Balcones Fault zone (BFZ). The Moho may be undetectable due to serpentinization of the upper mantle from water leaking through the BFZ, a possibility supported by the existence of a low velocity anomaly in the upper mantle beneath the BFZ found by surface wave modeling. Ps and Sp RFs also found evidence for a low velocity zone in the 50-70 km depth interval near the shoreline of the GCP. Ps RF imaging suggests this LVZ may be a piece of subducted lower crust emplaced during the Ouachita orogeny with a trapped mantle wedge above it. These observations are supported by gravity modeling.

  16. Modeling phosphorus cycling in a well-mixed coastal plain estuary

    NASA Astrophysics Data System (ADS)

    Lebo, Martin E.; Sharp, Jonathan H.

    1992-09-01

    Phosphorus cycling in the Delaware Estuary was examined during 1986-88 using numerical methods to calculate fluxes and estimate net regeneration. In the tidal river, the flux of total phosphorus (TP) increased threefold compared to Delaware River due to municipal inputs, with most of TP flux as dissolved inorganic phosphate (DIP, 56-59%). This observed increase in TP flux in the river, however, is much lower than expected, given known inputs. A mass balance for TP in the river indicated that a large fraction (44-67%) of TP inputs was retained mainly through geochemical processes. Phosphorus cycling in Delaware Bay, in contrast, was dominated by biological uptake and recycling. Within the bay, DIP input from the tidal river was transformed into phytoplankton biomass; the relative flux of particulate phosphorus (PP) increased from 35% of total flux into the bay to 62% at the month due to a 52% increase in mean PP flux. The biological dominance of P cycling in the bay resulted in strong seasonal variations in TP flux; during the annual winter-spring bloom, TP was retained in the bay (53-56%), while the bay was a source (+52%) of TP during the fall. Throughout the year, except during the spring, regenerated DIP was sufficient to supply 102±19, 94±10, and 95±6% of phytoplankton P-demand in the upper, middle, and lower bay respectively. During the spring, there was an imbalance between uptake and regeneration resulting in DIP depletion. A comparison of processes contributing to total regeneration indicated that 71-97% of apparent regeneration occurred within the water column, with sediment DIP release contributing an additional 3-25%. On an annual basis, 84% of TP entering the salinity gradient of the estuary was exported to coastal waters.

  17. Modern Landform Distribution of the Gilbert River Distributive Fluvial System (DFS) and Predictions Regarding Ancient Coastal Plain Progradational Successions

    NASA Astrophysics Data System (ADS)

    McNamara, K. C.; Weissmann, G. S.; Scuderi, L. A.; Owen, A.; Nichols, G. J.; Hartley, A. J.

    2011-12-01

    cross-stratification, brackish fossils, inclined heterolithic stratification) that cut into underlying foreshore strata and laterally equivalent fine-grained strata, overlain by 2) medial deposits of coarsening-upward packages due to avulsion and well-developed, laterally extensive mature paleosols, topped by 3) proximal deposits consisting of amalgamated sandstone bodies separated by regionally discontinuous erosional surfaces and relatively rare, well-drained, immature paleosols. Thus, progradational successions should exhibit an upsection increase in grain size, sand:mud ratios, and channel downcutting. Coastal plain fluvial and marginal marine progradational successions have proven to be important hydrocarbon and carbon dioxide sequestration reservoirs, coal accumulations, and aquifers. However, existing fluvial facies models used to predict sandbody distribution and connectivity are typically based on aggradational valley fill successions at the outcrop- and borehole-scale.

  18. The Morphologic Evolution of the Amazon Coastal Plain, Cabo Norte, Amapa, Brazil: The Need for Integrated Investigation on the Internal Continental Shelf.

    NASA Astrophysics Data System (ADS)

    Silveira, O.; Santos, V. F.; Takiyama, L. R.

    2007-05-01

    The north brazilian coastal region is submitted to the conjunction of three major forcing: 1) Atmospheric, related to the wind and precipitation regimen and controlling the climatic seasonality and the local rivers hydrology; 2) Oceanic, result of the general oceanic circulation (North Equatorial Current-NEC) and it modulation with the atmospheric forcing (North Brazilian Coastal Current reflection), and 3) Amazonic, which is a result of the sedimentary transport from Amazon river, being itself under the influence of the atmospheric and oceanic forcing. Their main characteristic are the proper periodicities and also variabilities expressed according multiples and differentiated scales of time and space, determining the structure and functioning of the coastal space, giving to the Amazon coast line a considerable environmental instability. The Amapa Coastal Plain shows important part of this environmental instability. Semidiurnal macro tides, strong currents and tidal bores acts over a low gradient coastal plain which evolutionary process are intrinsically related with tectonic and geological settings. Two main areas can be distinguished in this scenario. The first one is the Amapa Lakes Region, developed over meanders of ancient drainages building a mosaic of low relief forms, with varied shapes, linked throughout communication channels. Two lacustrine belts showing alignments with the main tectonic traces were recognized beginning at the internal limit of the coastal plain, flowing southeast through the Tabaco Creek until reach the Araguari River. In it way it conform the Occidental and Meridional Belts represented by shallow lakes, totally dependent of Tartarugal River discharge and surrounded by enormous areas of peat highly sensitive to fire during the regional low discharge. Light blue clays, peat and a package of tidal deposits with fluidization structures were recognized close to Araguari River, suggesting deposition during high sea level. The second area

  19. Sensor-based soil water monitoring to more effectively manage agricultural water resources in coastal plain soils

    NASA Astrophysics Data System (ADS)

    Bellamy, Christopher A.

    Cotton (Gossypium hirsutum L.) is widely grown in the United States with 5.7 million ha grown nationally and 1.2 million ha grown in the humid southeastern states in 2005. From 1969 to 2003, agricultural irrigated farmland acreage and total water applied increased by over 40% and 11% respectively to include a total of 55.3 million acres in 2002. Combined with recent and more frequent drought periods and legal water conflicts between states, there has been an increased interest in more effective southeastern water management, thus making the need to develop improved irrigation scheduling methods and enhanced water use efficiency of cotton cultivars. Several irrigation scheduling methods (soil moisture monitoring, pan evaporation, and climate based) tested at Clemson and elsewhere have shown that sensor-based irrigation significantly increased cotton yields and provided a monetary savings compared to other methods. There is however limited information on capacitance based soil moisture analysis techniques in the southeastern coastal plain soils and also limited locally developed crop coefficients used in scheduling the ET based treatments. The first objective of this study was to determine and improve the feasibility of utilizing sensor-based soil water monitoring techniques in Southeastern Coastal Plain soils to more effectively manage irrigation and increase water use efficiency of several cotton cultivars. The second objective was to develop two weighing lysimeters equipped with wireless data acquisition system to determine a crop coefficient for cotton under southeastern humid conditions. Two multi-sensor capacitance probes, AquaSpy(TM) and Sentek EnviroSCAN RTM, were calibrated in this study. It was found that positive linear calibrations can be used to describe the relationship between the soil volumetric moisture content (VMC) and sensor readings found for both probes and that multi-sensor capacitance probes can be used to accurately measure volumetric soil

  20. Simulation of proposed increases in ground-water withdrawals on the Atlantic City 800-foot sand, New Jersey coastal plain

    USGS Publications Warehouse

    Pope, Daryll A.

    2006-01-01

    The confined Atlantic City 800-foot sand and the unconfined Kirkwood-Cohansey aquifer system (surficial aquifer) are major sources of water for southeastern New Jersey. Because of recent concerns about streamflow depletion resulting from ground-water withdrawals and the potential ecological effects on stream habitat in the area, the focus on future withdrawals has been shifted away from the surficial aquifer to the confined Atlantic City 800-foot sand until the effects of increased withdrawals from the surficial aquifer can be investigated. A study was conducted to evaluate the effects of seven proposed increases in ground-water withdrawals from the Atlantic City 800-foot sand and the Kirkwood-Cohansey aquifer system on the Atlantic City 800-foot sand. The proposed withdrawals are increases above the 2004 allocated rates (full allocation). The effects of full-allocation ground-water withdrawals and the cumulative effect of withdrawals for each of seven proposed increases in withdrawals were simulated using three previously published ground-water flow models: the New Jersey Coastal Plain Regional Aquifer System Analysis model, the Coastal Plain Optimization model, and a model of the Atlantic City 800-foot sand in Atlantic County, New Jersey. These models were used to simulate changes in water levels, the source supplying the increased ground-water flow, and the effects on saltwater movement towards production wells in Cape May County as a result of the proposed increased withdrawals at proposed or existing wells. The results of the simulations represent the effects of the proposed increase from full-allocation withdrawals to an additional 1,825 Mgal/yr (million gallons per year) from the Atlantic City 800-foot sand and an additional 1,045 Mgal/yr from the deep part of the Kirkwood-Cohansey aquifer system near the updip limit of the Atlantic City 800-foot sand. Most of the simulated decline in water levels in Atlantic County occurred as the result of the proposed

  1. Widespread Degradation of Ice Wedges on the Arctic Coastal Plain in Northern Alaska in Response to the Recent Warmer Climate

    NASA Astrophysics Data System (ADS)

    Shur, Y.; Jorgenson, M. T.; Pullman, E. R.

    2003-12-01

    The continuous permafrost on the Arctic Coastal Plain in northern Alaska has been considered stable because permafrost temperatures remain low, even with an increase of several degrees during the last decades. Ice wedges, however, are particularly susceptible to degradation because only a very thin layer of permafrost (the transient layer) exists between the ice and the bottom of the active layer. An increase in the active layer during unusually warm periods causes the thawing front to encounter the underlying ice wedges and initiate degradation. Field observations and photogrammetric analysis of 1945, 1979, and 2001 aerial photography indicate that there has been widespread degradation of the ice wedges on the Arctic Coastal Plain west of the Colville Delta over the recent 57-year period, and indications are that most of the degradation occurred during the last two decades. Field sampling at 46 polygonal troughs and their intersections showed that ice wedge degradation has been relatively recent as indicated by newly drowned vegetation. We found thermokarst was widespread on a variety of terrain conditions, but most prevalent on, ice-rich centers of old drained lake basins and alluvial-marine terraces, which have the greatest ice wedge development in the studied landscape. Ice wedges on these terrains typically occupy from 10 to 20 % of the upper permafrost. We attributed the natural degradation to warm weather during the last decades, because disturbance of the ground surface, which could have similar impact on ice wedges, was not evident. While, ice-wedge degradation probably has been periodically occurring at low rates over the preceding centuries, it has greatly accelerated during the last several decades. We identified six stages of ice-wedge degradation and stabilization. They include: (1) the loss of transient layer of upper permafrost above ice wedges, leading to enhanced nutrient availability and vegetative growth; (2) thawing of ice wedges and surface

  2. Developing effective ground and space-based soil moisture sensing techniques for irrigating cotton in coastal plain soils

    NASA Astrophysics Data System (ADS)

    Qiao, Xin

    Irrigation scheduling based on soil moisture sensor readings has gained popularity in the past few decades since it can enhance crop yield while saving water. Such method is limited since the representativeness of an individual soil moisture sensor measurement is questionable in a large field with variable soil type and texture. The optimum location of soil moisture sensors needs to be determined within such a production field for effective sensor-based irrigation scheduling. Therefore, the first object of this study was to investigate the optimum sensor location and the number of moisture sensors required for irrigating cotton in coastal plain soils. Replicated tests were conducted during 2012, 2013, and 2014 growing seasons in a cotton field located at the Edisto Research and Education Center of Clemson University, on a typical coastal plain soil. The test field was divided into different management zones based on soil electrical conductivity (EC) measurements. Soil moisture sensors including AquaSpy, Sentek EasyAg-50, Decagon EC-5, Watermark 200SS, and 503 DR Hydroprobe neutron probe access tubes were installed side by side in plots of each management zone. Irrigation treatments were based on sensor readings from various management zones. Results showed that irrigation based on sensor readings from higher electrical conductivity zones, can stabilize or even enhance yield while increasing water use efficiency (WUE) significantly. The second objective of this study was to evaluate the performance of soil moisture sensors mentioned above to determine the most accurate and affordable sensor technology for irrigation scheduling. Season long soil moisture readings of AquaSpy, Sentek EasyAg-50, Decagon EC-5, and Watermark 200SS sensors were collected and compared to neutron probe readings. The results showed that Sentek EasyAg-50 sensor performed the best among tested sensors compared to neutron probe readings with coefficient of determination, R2 = 0.847 and root mean

  3. Structural and stratigraphic framework and spatial distribution of permeability of the Atlantic coastal plain, North Carolina to New York

    USGS Publications Warehouse

    Brown, Philip Monroe; Miller, James A.; Swain, Frederick Morrill

    1972-01-01

    This report describes and interprets the results of a detailed subsurface mapping program undertaken in that part of the Atlantic Coastal Plain which extends from the South Carolina and North Carolina border through Long Island, N.Y. Data obtained from more than 2,200 wells are analyzed. Seventeen chronostratigraphic units are mapped in the subsurface. They range in age from Jurassic(?) to post-Miocene. The purpose of the mapping program was to determine the external and internal geometry of mappable chronostratigraphic units and to derive and construct a permeability-distribution network for each unit based upon contrasts in the textures and compositions of its contained sediments. The report contains a structure map and a combined isopach, lithofacies, and permeability-distribution map for each of the chronostratigraphic units delineated in the subsurface. In addition, it contains a map of the top of the basement surface. These maps, together with 36 stratigraphic cross sections, present a three-dimensional view of the regional subsurface hydrogeology. They provide focal points of reference for a discussion of regional tectonics, structure, stratigraphy, and permeability distribution. Taken together and in chronologic sequence, the maps constitute a detailed sedimentary model, the first such model to be constructed for the middle Atlantic Coastal Plain. The chronostratigraphic units mapped record a structural history dominated by lateral and vertical movement along a system of intersecting hinge zones. Taphrogeny, related to transcurrent faulting, is the dominant type of deformation that controlled the geometry of the sedimentary model. Twelve of the seventeen chronostratigraphic units mapped have depositional alinements and thickening trends that are independent of the present-day configuration of the underlying basement surface. These 12 units, classified as genetically unrooted units, are assigned to a first-order tectonic stage. A structural model is proposed

  4. Distribution of autumn-staging Lesser Snow Geese on the northeast coastal plain of Alaska [Distribución de chen caerulescens a través de su congregación otonal

    USGS Publications Warehouse

    Robertson, Donna G.; Brackney, Alan W.; Spindler, Michael A.; Hupp, Jerry W.

    1997-01-01

    We conducted aerial surveys of Lesser Snow Geese (Chen caerulescens caerulescens) during autumn staging on the coastal plain of the Arctic National Wildlife Refuge (ANWR) in northeast Alaska from late August through September, 1982 - 1993. We evaluated numbers and distribution of Snow Geese that staged on the ANWR, compared abundance of birds among 5 x 5-km cells used frequently (5 - 8 yr), periodically (3 - 4 yr), or infrequently (1 - 2 yr), and examined distribution changes within years. Maximum numbers of Snow Geese observed annually were highly variable (range 12,828 - 309,225). Snow Goose flocks occurred across 605,000 ha of the coastal plain, but used some areas more frequently than others. Frequently used cells (38 of 363 cells in the study area) were non-randomly distributed and primarily occurred on the central coastal plain between the wet coastal and steep foothills regions. Abundance of geese was greatest in frequently used, intermediate in periodically used, and lowest in infrequently used cells. Within years, Snow Goose numbers and flock locations varied between surveys, possibly because geese moved to different foraging areas during staging. The widespread distribution and annual variability in numbers of Snow Geese on the coastal plain was likely because birds used foraging habitats that were spatially and temporally heterogeneous. The ANWR coastal plain is an important component of the fall-staging area used by Snow Geese that nest in the western Canadian Arctic. Management decisions that affect the region should reflect its value to migrating Snow Geese.

  5. Digital-simulation and projection of head changes in the Potomac-Raritan-Magothy aquifer system, coastal plain, New Jersey

    USGS Publications Warehouse

    Luzier, James E.

    1980-01-01

    (1) no increase in ground-water extractions; (2) continued growth in ground-water extractions at the rate of 1.7 and 3 percent annually; and (3) continued growth in ground-water extractions at the rate of 3 percent annually, in conjunction with the activitation of a freshwater head barrier in the fresh-salty transition zone. Under the first set of conditions, further head reduction would cease over very large regions within two years. Under the second set of conditions involving a 3 percent growth rate similar to that experienced during the simulation period, the broad cone of depression already encompassing most of the New Jersey Coastal Plain would broaden and deepen. Heads would range from 60 to 160 feet below National Geodetic Vertical Datum of 1929. The reduction of head after 1973 would approach 90 feet in some areas. The resultant steeper hydraullic gradients would accelerate the rate of movement of salty ground water toward the pumping centers. A freshwater head barrier could be established in the transition zone to prevent migration of salty ground water across a 35-mile stretch in Gloucester, Camden, and Burlington Counties. A line of injection wells would be required, with total rates of injection to the head barrier ranging from about 56 cubic feet per second in 1984 to about 95 cubic feet per second in 2000. Barrier recharge rates would be equivalent to about 20 percent of the ground water pumped in the fine-grid area in any particular year for a 3 percent increase in extractions.

  6. Zinc, cadmium and manganese uptake by soybean from two zinc- and cadmium-amended Coastal Plain soils

    SciTech Connect

    White, M.C.; Chaney, R.L.

    1980-03-01

    Two Coastal Plain soils were used to evaluate the effects of organic matter and Fe and Mn hydrous oxides on Zn phytotoxicity, and on Zn, Cd, and Mn uptake by soybean seedlings. Fertilized Pocomoke sl and Sassafras sl were limed to pH 5.5 and 6.3 with CaCO/sub 3/ when adding Zn (six levens between 1.3 and 196 mg/kg at pH 5.5; seven levels between 1.3 and 524 mg/kg at pH 6.3). Cadmium was added at 1% of the added Zn. Beeson soybean (Glycine max L. Merr.) was grown 4 weeks, and the trifoliolate leaves evaluated for dry weight yield and for their Zn, Cd, and Mn concentrations. The higher organic matter Pocomoke soil was more effective than the Sassafras soil in reducing metal uptake, and Zn phytoxicity. Foliar Zn levels associated with yield reduction of soybean grown on Pocomoke differed with soil pH. Cadmium uptake was significantly lower on the Pocomoke soil. Foliar Mn increased to reported phytotoxic levels (> 500 mg/kg) with increased added Zn only on the Sassafras soil at pH 6.3. DTPA-extractable Zn and Cd were linear functions of added Zn and Cd for both soils; 0.01M CaCl/sub 2/-extractable Zn and Cd were curvilinear (increasing slope) functions for the Sassafras and linear for the Pocomoke soil. Thus, soil type can strongly influence Zn, Cd, and Mn uptake as well as Zn phytotoxicity to soybean. Soil organic matter appears to be more important than hydrous oxides of Fe and Mn in moderating the effects of excessive soil Zn and limiting Zn and Cd uptake. Induced metal toxicities (Mn) may depend on many factors, and should be considered an integral part of any characterization of specific metal phytotoxicities (e.g. Zn).

  7. Uranium-series coral ages from the US Atlantic Coastal Plain-the "80 ka problem" revisited

    USGS Publications Warehouse

    Wehmiller, J. F.; Simmons, K.R.; Cheng, H.; Edwards, R. Lawrence; Martin-McNaughton, J.; York, L.L.; Krantz, D.E.; Shen, C.-C.

    2004-01-01

    Uranium series coral ages for emergent units from the passive continental margin US Atlantic Coastal Plain (ACP) suggest sea level above present levels at the end of marine oxygen isotope stage (MIS) 5, contradicting age-elevation relations based on marine isotopic or coral reef models of ice equivalent sea level. We have reexamined this problem by obtaining high precision 230Th/238U and 231Pa/235U thermal ionization mass spectrometric ages for recently collected and carefully cleaned ACP corals, many in situ. We recognize samples that show no evidence for diagenesis on the basis of uranium isotopic composition and age concordance. Combining new and earlier data, among those ages close to or within the age range of MIS 5, over 85% cluster between 65 and 85 ka BP. Of the corals that we have analyzed, those that show the least evidence for diagenesis on the basis of uranium isotopic composition and age concordance have ages between 80 and 85 ka BP, consistent with a MIS 5a correlation. The units from which these samples have been collected are all emergent and have elevations within ???3-5m of those few units where early stage 5 (???125,000 ka BP) coral ages have been obtained. The ACP appears to record an unusual history of relative sea level throughout MIS 5, a history that is also apparent in the dated coral record for Bermuda. We speculate that this history is related to the regional (near-to intermediate-field) effects of ancestral Laurentide Ice sheets on last interglacial shorelines of the western North Atlantic. ?? 2004 Elsevier Ltd and INQUA. All rights reserved.

  8. Reconnaissance of Organic Wastewater Compounds at a Concentrated Swine Feeding Operation in the North Carolina Coastal Plain, 2008

    USGS Publications Warehouse

    Harden, Stephen L.

    2009-01-01

    Water-quality and hydrologic data were collected during 2008 to examine the occurrence of organic wastewater compounds at a concentrated swine feeding operation located in the North Carolina Coastal Plain. Continuous groundwater level and stream-stage data were collected at one monitoring well and one stream site, respectively, throughout 2008. One round of environmental and quality-control samples was collected in September 2008 following a period of below-normal precipitation and when swine waste was not being applied to the spray fields. Samples were collected at one lagoon site, seven shallow groundwater sites, and one surface-water site for analysis of 111 organic wastewater compounds, including household, industrial, and agricultural-use compounds, sterols, pharmaceutical compounds, hormones, and antibiotics. Analytical data for environmental samples collected during the study provide preliminary information on the occurrence of organic wastewater compounds in the lagoon-waste source material, groundwater beneath fields that receive spray applications of the lagoon wastes, and surface water in the tributary adjacent to the site. Overall, 28 organic wastewater compounds were detected in the collected samples, including 11 household, industrial, and agricultural-use compounds; 3 sterols; 2 pharmaceutical compounds; 5 hormones; and 7 antibiotics. The lagoon sample had the greatest number (20) and highest concentrations of compounds compared to groundwater and surface-water samples. The antibiotic lincomycin had the maximum detected concentration (393 micrograms per liter) in the lagoon sample. Of the 11 compounds identified in the groundwater and surface-water samples, all with reported concentrations less than 1 microgram per liter, only lincomycin identified in groundwater at 1 well and 3-methyl-1H-indole and indole identified in surface water at 1 site also were identified in the lagoon waste material.

  9. Ultramafic inclusions and host alkali olivine basalts of the southern coastal plain of the Red Sea, Kingdom of Saudi Arabia

    USGS Publications Warehouse

    Ghent, Edward D.; Coleman, Robert Griffin; Hadley, Donald G.

    1979-01-01

    A variety of mafic and ultramafic inclusions occur within the pyroclastic components of the Al Birk basalt, erupted on the southern Red Sea coastal plain of Saudi Arabia from Pleistocene time to the present. Depleted harzburgites are the only inclusions contained within the basalts that were erupted through Miocene oceanic crust (15 km thick) in the vicinity of Jizan, whereas to the north in the vicinity of Al Birk, alkali basalts that were erupted through a thicker Precambrian crust (48 km thick) contain mixtures of harzburgites, cumulate gabbro, and websterite inclusions accompanied by large (> 2 cm) megacrysts of glassy alumina-rich clinopyroxene, plagioclase, and spinel. Microprobe analyses of individual minerals from the harzburgites, websterites, and cumulate gabbros reveal variations in composition that can be related to a complex mantle history during the evolution of the alkali basalts. Clinopyroxene and plagioclase megacrysts may represent early phases that crystallized from the alkali olivine basalt magma at depths less than 35 km. Layered websterites and gabbros with cumulate plagioclase and clinopyroxene may represent continuing crystallization of the alkali olivine basalt magma in the lower crust when basaltic magma was not rapidly ascending. It is significant that the megacrysts and cumulate inclusions apparently form only where the magmas have traversed the Precambrian crust, whereas the harzburgite-bearing basalts that penetrated a much thinner Miocene oceanic crust reveal no evidence of mantle fractionation. These alkali olivine basalts and their contained inclusions are related in time to present-day rifting in the Red Sea axial trough. The onshore, deep-seated, undersaturated magmas are separated from the shallow Red Sea rift subalkaline basalts by only 170 km. The contemporaneity of alkaline olivine and subalkaline basalts requires that they must relate directly to the separation of the Arabian plate from the African plate.

  10. Nitrogen transport and transformations in a coastal plain watershed: Influence of geomorphology on flow paths and residence times

    USGS Publications Warehouse

    Tesoriero, A.J.; Spruill, T.B.; Mew, H.E.; Farrell, K.M.; Harden, S.L.

    2005-01-01

    Nitrogen transport and groundwater-surface water interactions were examined in a coastal plain watershed in the southeastern United States. Groundwater age dates, calculated using chlorofluorocarbon and tritium concentrations, along with concentrations of nitrogen species and other redox-active constituents, were used to evaluate the fate and transport of nitrate. Nitrate is stable only in recently recharged (<10 years) water found in the upper few meters of saturated thickness in the upland portion of a surficial aquifer. Groundwater with a residence time between 10 and 30 years typically has low nitrate and elevated excess N2 concentrations, indications that denitrification has reduced nitrate concentrations. Groundwater older than 30 years also has low nitrate concentrations but contains little or no excess N2, suggesting that this water did not contain elevated concentrations of nitrate along its flow path. Nitrate transport to streams varies between first- and third-order streams. Hydrologic, lithologic, and chemical data suggest that the surficial aquifer is the dominant source of flow and nitrate to a first-order stream. Iron-reducing conditions occur in groundwater samples from the bed and banks of the first-order stream, suggesting that direct groundwater discharge is denitrified prior to entering the stream. However, nitrogen from the surficial aquifer is transported directly to the stream via a tile drain that bypasses these reduced zones. In the alluvial valley of a third-order stream the erosion of a confining layer creates a much thicker unconfined alluvial aquifer with larger zones of nitrate stability. Age dating and chemical information (SiO 2, Na/K ratios) suggest that water in the alluvial aquifer is derived from short flow paths through the riparian zone and/or from adjacent streams during high-discharge periods. Copyright 2005 by the American Geophysical Union.

  11. Impacts of shore expansion and catchment characteristics on lacustrine thermokarst records in permafrost lowlands, Alaska Arctic Coastal Plain

    USGS Publications Warehouse

    Lenz, Josefine; Jones, Benjamin M.; Wetterich, Sebastian; Tjallingii, Rik; Fritz, Michael; Arp, Christopher D.; Rudaya, Natalia; Grosse, Guido

    2016-01-01

    Arctic lowland landscapes have been modified by thermokarst lake processes throughout the Holocene. Thermokarst lakes form as a result of ice-rich permafrost degradation, and they may expand over time through thermal and mechanical shoreline erosion. We studied proximal and distal sedimentary records from a thermokarst lake located on the Arctic Coastal Plain of northern Alaska to reconstruct the impact of catchment dynamics and morphology on the lacustrine depositional environment and to quantify carbon accumulation in thermokarst lake sediments. Short cores were collected for analysis of pollen, sedimentological, and geochemical proxies. Radiocarbon and 210Pb/137Cs dating, as well as extrapolation of measured historic lake expansion rates, were applied to estimate a minimum lake age of ~1400 calendar years BP. The pollen record is in agreement with the young lake age as it does not include evidence of the “alder high” that occurred in the region ~4000 cal yr BP. The lake most likely initiated from a remnant pond in a drained thermokarst lake basin (DTLB) and deepened rapidly as evidenced by accumulation of laminated sediments. Increasing oxygenation of the water column as shown by higher Fe/Ti and Fe/S ratios in the sediment indicate shifts in ice regime with increasing water depth. More recently, the sediment source changed as the thermokarst lake expanded through lateral permafrost degradation, alternating from redeposited DTLB sediments, to increased amounts of sediment from eroding, older upland deposits, followed by a more balanced combination of both DTLB and upland sources. The characterizing shifts in sediment sources and depositional regimes in expanding thermokarst lakes were, therefore, archived in the thermokarst lake sedimentary record. This study also highlights the potential for Arctic lakes to recycle old carbon from thawing permafrost and thermokarst processes.

  12. Modeling Storm Water Runoff and Soil Interflow in a Managed Forest, Upper Coastal Plain of the Southeast US.

    SciTech Connect

    Callahan, T.J.; Cook, J.D.; Coleman, Mark D.; Amatya, Devendra M.; Trettin, Carl C.

    2004-08-01

    The Forest Service-Savannah River is conducting a hectare-scale monitoring and modeling study on forest productivity in a Short Rotation Woody Crop plantation at the Savannah River Site, which is on Upper Coastal Plain of South Carolina. Detailed surveys, i.e., topography, soils, vegetation, and dainage network, of small (2-5 ha) plots have been completed in a 2 square-km watershed draining to Fourmile Creek, a tributary of the Savannah River. We wish to experimentally determine the relative importance of interflow on water yield and water quality at this site. Interflow (shallow subsurface lateral flow) can short-circuit rainfall infiltration, preventing deep seepage and resulting in water and chemical residence times in the watershed much shorter than that if deep seepage were the sole component of infiltration. The soil series at the site (Wagram, Dothan, Fuquay, Ogeechee, and Vaucluse) each have a clay-rich B horizon of decimeter-scale thickness at depths of 1-2 m below surface. As interflow is affected by rainfall intensity and duration and soil properties such as porosity, permeability, and antecedent soil moisture, our calculations made using the Green and Ampt equation show that the intensity and duration of a storm event must be greater than about 3 cm per hour and 2 hours, respectively, in order to initiate interflow for the least permeable soils series (Vaucluse). Tabulated values of soil properties were used in these preliminary calculations. Simulations of the largest rainfall events from 1972-2002 data using the Green and Ampt equation provide an interflow: rainfall ratio of 0 for the permeable Wagram soil series (no interflow) compared to 0.46 for the less permeable Vaucluse soil series. These initial predictions will be compared to storm water hydrographs of interflow collected at the outflow point of each plot and refined using more detailed soil property measurements.

  13. Seasonal and multiannual roost use by Rafinesque's Big-eared Bats in the Coastal Plain of South Carolina.

    SciTech Connect

    Loeb, Susan, C.; Zarnoch, Stanley, J.

    2011-12-01

    Little is known about factors affecting year-round use of roosts by Rafinesque's big-eared bats (Corynorhinus rafinesquii) or the long-term fidelity of this species to anthropogenic or natural roosts. The objectives of this study were to test whether seasonal use of roosts by Rafinesque's big-eared bats varied with roost type and environmental conditions within and among seasons and to document multiannual use of natural and anthropogenic structures by this species. We inspected 4 bridges, 1 building, and 59 tree roosts possessing basal cavity openings; roosts were inspected at least once per week from May through October in every year from 2005 through 2008 and once a month from November through April in every year from 2005 through 2009. We found that use of anthropogenic roosts was significantly greater than the use of tree roosts in summer but that the use of structure types did not differ in other seasons. There was significant seasonal variation in use of anthropogenic and tree roosts. Anthropogenic roost use was higher in summer than in all other seasons. There was no significant difference in tree use among spring, summer, and fall, but use in winter was significantly lower in 2 years of the study. Overall use of anthropogenic and tree roosts was positively related to minimum temperature, but the relationship between use of roosts and minimum temperature varied among seasons. Bats showed multiannual fidelity ({ge} 4 years) to all anthropogenic roosts and to some tree roosts, but fidelity of bats to anthropogenic roosts was greater and more consistent than to tree roosts. Our data indicate that Rafinesque's big-eared bats responded differently to environmental conditions among seasons; thus, a variety of structure types and characteristics are necessary for conservation of these bats. We suggest long-term protection of roost structures of all types is necessary for conservation of Rafinesque's big-eared bats in the southeast Coastal Plain.

  14. Impact of switchgrass biochars with supplemental nitrogen on carbon-nitrogen mineralization in highly weathered Coastal Plain Ultisols.

    PubMed

    Sigua, G C; Novak, J M; Watts, D W; Szögi, A A; Shumaker, P D

    2016-02-01

    Although an increase in soil fertility is the most frequently reported benefit linked to adding biochar to soils, there is still a need to pursue additional research that will improve our understanding on the impact of soil fertility enhancement because the effect could vary greatly between switchgrass (Panicum virgatum, L) residues (USG) and switchgrass biochars (SG). We hypothesized that SG with supplemental nitrogen (N) would deliver more positive effects on carbon (C) and N mineralization than USG. The objective of this study was to evaluate the effects of USG and SG, with or without supplemental inorganic N fertilizer on C and N mineralization in highly weathered Coastal Plain Ultisols. The application rate for SG and USG based on a corn yield goal of 112 kg ha(-1) was 40 Mg ha(-1). Inorganic N was added at the rate of 100 kg N ha(-1), also based on a corn yield of 7.03 tons ha(-1). Experimental treatments were: control (CONT) soil; control with N (CONT + N); switchgrass residues (USG); USG with N (USG + N); switchgrass biochars at 250 °C (250SG); SG at 250 °C with N (250SG + N); SG at 500 °C (500SG); and SG at 500 °C with N (500SG + N). Cumulative and net CO2-C evolution was increased by the additions of SG and USG especially when supplemented with N. Soils treated with 250SG (8.6 mg kg(-1)) had the least concentration of total inorganic nitrogen (TIN) while the greatest amount of TIN was observed from the CONT + N (19.0 mg kg(-1)). Our results suggest that application of SG in the short term may cause N immobilization resulting in the reduction of TIN. PMID:26688249

  15. Impacts of Enhanced-Efficiency Nitrogen Fertilizers on Greenhouse Gas Emissions in a Coastal Plain Soil under Cotton.

    PubMed

    Watts, Dexter B; Runion, G Brett; Smith Nannenga, Katy W; Torbert, H Allen

    2015-11-01

    Enhanced-efficiency N fertilizers (EENFs) have the potential to increase crop yield while decreasing soil N loss. However, the effect of EENFs on greenhouse gas (GHG) emissions from different agricultural systems is not well understood. Thus, studies from a variety of locations and cropping systems are needed to evaluate their impact. An experiment was initiated on a Coastal Plain soil under cotton ( L.) production for comparing EENFs to traditional sources. Nitrogen sources included urea, ammonia sulfate (AS), urea-ammonia sulfate (UAS), controlled-release, polymer-coated urea (Environmental Smart Nitrogen [ESN]), stabilized granular urea (SuperU), poultry litter (PL), poultry litter plus AgrotainPlus (PLA), and an unfertilized control. Carbon dioxide (CO), nitrous oxide (NO), and methane (CH) fluxes were monitored regularly after fertilization through harvest from 2009 to 2011 using a closed-chamber method. Poultry litter and PLA had higher CO flux than other N treatments, while ESN and SU were generally lowest following fertilization. Nitrous oxide fluxes were highly variable and rarely affected by N treatments; PL and PLA were higher but only during the few samplings in 2010 and 2011. Methane fluxes were higher in 2009 (wet year) than 2010 or 2011, and N treatments had minimal impact. Global warming potential (GWP), calculated from cumulative GHG fluxes, was highest with PL and PLA and lowest for control, UAS, ESN, and SU. Results suggest that PL application to cotton increases GHG flux, but GHG flux reductions from EENFs were infrequently different from standard inorganic fertilizers, suggesting their higher cost may render them presently impractical.

  16. Impacts of Enhanced-Efficiency Nitrogen Fertilizers on Greenhouse Gas Emissions in a Coastal Plain Soil under Cotton.

    PubMed

    Watts, Dexter B; Runion, G Brett; Smith Nannenga, Katy W; Torbert, H Allen

    2015-11-01

    Enhanced-efficiency N fertilizers (EENFs) have the potential to increase crop yield while decreasing soil N loss. However, the effect of EENFs on greenhouse gas (GHG) emissions from different agricultural systems is not well understood. Thus, studies from a variety of locations and cropping systems are needed to evaluate their impact. An experiment was initiated on a Coastal Plain soil under cotton ( L.) production for comparing EENFs to traditional sources. Nitrogen sources included urea, ammonia sulfate (AS), urea-ammonia sulfate (UAS), controlled-release, polymer-coated urea (Environmental Smart Nitrogen [ESN]), stabilized granular urea (SuperU), poultry litter (PL), poultry litter plus AgrotainPlus (PLA), and an unfertilized control. Carbon dioxide (CO), nitrous oxide (NO), and methane (CH) fluxes were monitored regularly after fertilization through harvest from 2009 to 2011 using a closed-chamber method. Poultry litter and PLA had higher CO flux than other N treatments, while ESN and SU were generally lowest following fertilization. Nitrous oxide fluxes were highly variable and rarely affected by N treatments; PL and PLA were higher but only during the few samplings in 2010 and 2011. Methane fluxes were higher in 2009 (wet year) than 2010 or 2011, and N treatments had minimal impact. Global warming potential (GWP), calculated from cumulative GHG fluxes, was highest with PL and PLA and lowest for control, UAS, ESN, and SU. Results suggest that PL application to cotton increases GHG flux, but GHG flux reductions from EENFs were infrequently different from standard inorganic fertilizers, suggesting their higher cost may render them presently impractical. PMID:26641321

  17. The use of mineralogic techniques as relative age indicators for weathering profiles on the Atlantic Coastal Plain, USA

    USGS Publications Warehouse

    Soller, D.R.; Owens, J.P.

    1991-01-01

    Textural, geochemical, and mineralogic study of soils and weathering profiles has led to the practice of applying varioys weathering parameters as relative age indicators. In our studies examined the entire thickness of weathered sediment (i.e., the weathering profile) for evidence of weathering-induced changes in both sand- and clay-sized mineralogy, and used two techniques for relative age determinations. These techniques were developed as tools to support geologic mapping. One of our techniques for determining relative ages is based on the depth of weathering as recorded by progressive loss of denrital sand-sized minerals upward in the weathering profile. This is our preferred tool, especially in areas where weathering profiles have been truncated. We have found a gradual trend of increasing loss of labile sand-sized minerals (e.g., hornblendes, feldspars) and increasing depth of weathering with increasing age of the deposit. Of significance to many research programs, this technique does not require expensive instruments such as an X-ray diffractometer. Our other technique depends on accumulation of stable, secondary clay-sized minerals in the upper part of the weathering profile. In our study area on the Atlantic Coastal Plain of the United States, the stable assemblage consists of vermiculite, kaolinite, gibbsite, and iron oxides and hydroxides. This technique can be effective for relative age determinations where profiles have not been truncated, and can provide useful information on depositional and erosional history. However, in areas of widespread erosion and profile truncation, such as the Carolinas, the utility of this technique for relative age determinations is limited. There, soils were partially or completely removed in many localities in relatively recent times. ?? 1991.

  18. Sampling design and procedures for fixed surface-water sites in the Georgia-Florida coastal plain study unit, 1993

    USGS Publications Warehouse

    Hatzell, H.H.; Oaksford, E.T.; Asbury, C.E.

    1995-01-01

    The implementation of design guidelines for the National Water-Quality Assessment (NAWQA) Program has resulted in the development of new sampling procedures and the modification of existing procedures commonly used in the Water Resources Division of the U.S. Geological Survey. The Georgia-Florida Coastal Plain (GAFL) study unit began the intensive data collection phase of the program in October 1992. This report documents the implementation of the NAWQA guidelines by describing the sampling design and procedures for collecting surface-water samples in the GAFL study unit in 1993. This documentation is provided for agencies that use water-quality data and for future study units that will be entering the intensive phase of data collection. The sampling design is intended to account for large- and small-scale spatial variations, and temporal variations in water quality for the study area. Nine fixed sites were selected in drainage basins of different sizes and different land-use characteristics located in different land-resource provinces. Each of the nine fixed sites was sampled regularly for a combination of six constituent groups composed of physical and chemical constituents: field measurements, major ions and metals, nutrients, organic carbon, pesticides, and suspended sediments. Some sites were also sampled during high-flow conditions and storm events. Discussion of the sampling procedure is divided into three phases: sample collection, sample splitting, and sample processing. A cone splitter was used to split water samples for the analysis of the sampling constituent groups except organic carbon from approximately nine liters of stream water collected at four fixed sites that were sampled intensively. An example of the sample splitting schemes designed to provide the sample volumes required for each sample constituent group is described in detail. Information about onsite sample processing has been organized into a flowchart that describes a pathway for each of

  19. Drainage network structure and hydrologic behavior of three lake-rich watersheds on the Arctic Coastal Plain, Alaska

    USGS Publications Warehouse

    Arp, C.D.; Whitman, M.S.; Jones, Benjamin M.; Kemnitz, R.; Grosse, G.; Urban, F.E.

    2012-01-01

    Watersheds draining the Arctic Coastal Plain (ACP) of Alaska are dominated by permafrost and snowmelt runoff that create abundant surface storage in the form of lakes, wetlands, and beaded streams. These surface water elements compose complex drainage networks that affect aquatic ecosystem connectivity and hydrologic behavior. The 4676 km2 Fish Creek drainage basin is composed of three watersheds that represent a gradient of the ACP landscape with varying extents of eolian, lacustrine, and fluvial landforms. In each watershed, we analyzed 2.5-m-resolution aerial photography, a 5-m digital elevation model, and river gauging and climate records to better understand ACP watershed structure and processes. We show that connected lakes accounted for 19 to 26% of drainage density among watersheds and most all channels initiate from lake basins in the form of beaded streams. Of the > 2500 lakes in these watersheds, 33% have perennial streamflow connectivity, and these represent 66% of total lake area extent. Deeper lakes with over-wintering habitat were more abundant in the watershed with eolian sand deposits, while the watershed with marine silt deposits contained a greater extent of beaded streams and shallow thermokarst lakes that provide essential summer feeding habitat. Comparison of flow regimes among watersheds showed that higher lake extent and lower drained lake-basin extent corresponded with lower snowmelt and higher baseflow runoff. Variation in baseflow runoff among watersheds was most pronounced during drought conditions in 2007 with corresponding reduction in snowmelt peak flows the following year. Comparison with other Arctic watersheds indicates that lake area extent corresponds to slower recession of both snowmelt and baseflow runoff. These analyses help refine our understanding of how Arctic watersheds are structured and function hydrologically, emphasizing the important role of lake basins and suggesting how future lake change may impact hydrologic

  20. A regional classification of the effectiveness of depressional wetlands at mitigating nitrogen transport to surface waters in the Northern Atlantic Coastal Plain

    USGS Publications Warehouse

    Ator, Scott W.; Denver, Judith M.; LaMotte, Andrew E.; Sekellick, Andrew J.

    2013-01-01

    Nitrogen from nonpoint sources contributes to eutrophication, hypoxia, and related ecological degradation in Atlantic Coastal Plain streams and adjacent coastal estuaries such as Chesapeake Bay and Pamlico Sound. Although denitrification in depressional (non-riparian) wetlands common to the Coastal Plain can be a significant landscape sink for nitrogen, the effectiveness of individual wetlands at removing nitrogen varies substantially due to varying hydrogeologic, geochemical, and other landscape conditions, which are often poorly or inconsistently mapped over large areas. A geographic model describing the spatial variability in the likely effectiveness of depressional wetlands in watershed uplands at mitigating nitrogen transport from nonpoint sources to surface waters was constructed for the Northern Atlantic Coastal Plain (NACP), from North Carolina through New Jersey. Geographic and statistical techniques were used to develop the model. Available medium-resolution (1:100,000-scale) stream hydrography was used to define 33,799 individual watershed catchments in the study area. Sixteen landscape metrics relevant to the occurrence of depressional wetlands and their effectiveness as nitrogen sinks were defined for each catchment, based primarily on available topographic and soils data. Cluster analysis was used to aggregate the 33,799 catchments into eight wetland landscape regions (WLRs) based on the value of three principal components computed for the 16 original landscape metrics. Significant differences in topography, soil, and land cover among the eight WLRs demonstrate the effectiveness of the clustering technique. Results were used to interpret the relative likelihood of depressional wetlands in each WLR and their likely effectiveness at mitigating nitrogen transport from upland source areas to surface waters. The potential effectiveness of depressional wetlands at mitigating nitrogen transport varies substantially over different parts of the NACP

  1. Chromium and nickel as indicators of source-to-sink sediment transfer in a Holocene alluvial and coastal system (Po Plain, Italy)

    NASA Astrophysics Data System (ADS)

    Amorosi, Alessandro

    2012-12-01

    A reliable quantitative estimate of changes in source-to-sink sediment transfer requires that high-resolution stratigraphic studies be coupled with accurate reconstructions of spatial and temporal variability of the sediment-routing system through time. Source-to-sink patterns from the contributing upland river catchments to the deltaic and coastal system are reconstructed from the Holocene succession of the Po Plain on the basis of selected geochemical indicators. Sediment supplied to the delta area by the major trunk river (the Po) exhibits naturally high Cr and Ni values, which invariably exceed the maximum permissible concentrations for unpolluted sites. This 'anomaly' reflects remarkable sediment contribution from ultramafic (ophiolitic) parent rocks cropping out in the Po drainage basin (Western Alps and NW Apennines). In contrast, alluvial and coastal plain deposits supplied by ophiolite-free, Apenninic catchments invariably display lower Cr and Ni contents. For constant sediment provenance domain, Cr and Ni distribution is observed to be controlled primarily by hydraulic sorting. Clay-silt deposits (floodplain, swamp and lagoon/bay facies associations) invariably show higher metal concentrations than their sandy counterparts (fluvial-channel, distributary-channel and beach-ridge facies associations). From a stratigraphic perspective, in sedimentary basins characterized by strong differences in sediment composition geochemical fingerprinting of individual facies associations framed by surfaces of chronostratigraphic significance is proposed as an invaluable approach towards an accurate quantitative assessment of sediment storage in alluvial and coastal depositional systems as opposed to volumetric reconstructions based on lithologic or geometric criteria alone.

  2. Social indicators study of Alaskan Coastal Villages I. Key informant summaries. Volume 2. Schedule B regions (Bristol Bay, Kodiak, Bering Straits). Final report

    SciTech Connect

    Brelsford, T.; Fienup-Riordan, A.; Jorgensen, J.; McNabb, S.; Petrivelli, P.

    1992-08-01

    The focus of this report is on Alaska Natives--Inupiaq and Yupik Eskimos, Athabascans, and Aleuts--for two important reasons: (1) Alaska Natives are numerically dominant populations in rural areas closest to potential offshore oil development sites and (2) their economic adjustments are most vulnerable to potential impacts from such development. This report is divided into Schedules A, B, and C. Comprising Schedules A and B are the study areas originally identified by Minerals Management Service for this study (North Slope, NANA, Bering Straits, Calista, Bristol Bay, Aleutian-Pribilof Islands, and Kodiak regions). Schedule C is comprised of communities that were added subsequent to the Exxon Valdez oil spill of 1989 in the Prince William Sound and Cook Inlet regions. One aim of this study was to document the attitudes and belief systems or ideologies about quality of life and well-being in the coastal, rural portions of Alaska.

  3. Early to middle Pleistocene Arctic coastal ice caps in the Northern Interior Plains of Canada, a comparison with northeastern Siberian coastal uplands

    NASA Astrophysics Data System (ADS)

    Duk-Rodkin, A.; Barendregt, R. W.; Velichko, A. A.; Galloway, J. M.; McNeil, D.

    2012-12-01

    A stratigraphic record of four to five ice-cap developments during the last 2.6 myr was discovered along the Northern Interior Plains (NIP) of the Canadian Continental Arctic Coast below 500 m elevation. Paleomagnetism, macrofossils, foraminifera, till fabrics and pebble lithologies were obtained from outcrops. This glacial stratigraphic record is less extensive than that found west of the continental divide in the Northern Canadian Cordillera, where at least 11 glaciations occurred in the last 2.7 Ma and where uplift along the south side of NW North America during the Pliocene set the stage for large scale glaciations. These coastal mountains and the continental divide created a double rain shadow effect that limited Pacific moisture reaching the NIP. East of the continental divide, moisture supply was only sufficient to form valley glaciers in five of the glacial periods that affected the Cordillera. The NIP was also affected by five glaciations. Ice-caps developed periodically and in the late Pleistocene, the Laurentide Ice Sheet covered all of the NIP. During interglacial times, the NIP experienced dry steppe conditions, similar to modern northern climates found in regions of extreme continentality. The geographic setting along the eastern Siberian coast is comparable to conditions of the NIP, but no record of glaciations exists from upland areas near the Arctic Ocean. Moisture supply and temperature were likely insufficient to form local ice caps at low coastal elevations (<600 m) during the Pleistocene; only in the mountains to the south did glaciers form. Climatic conditions leading to the formation of ice-caps in the NIP may be related to local influences, such as an open or partially open Arctic Ocean. Ice caps may have formed during interglacial times when warm waters periodically entered the Arctic Ocean. There is sufficient data linking marine life from the Bering Sea to western Canadian Arctic to support the idea that warm waters from the NE Pacific

  4. Herbivory and soil moisture drive long-term patterns of vegetation structure and function in Alaskan coastal tundra: results from resampling historic exclosures at Barrow

    NASA Astrophysics Data System (ADS)

    Johnson, D. R.; Lara, M. J.; Shaver, G. R.; Tweedie, C.

    2010-12-01

    Herbivores can be strong drivers of vegetation structure whose effects often vary depending on such things as primary productivity, the species makeup and structure of plants and herbivores, and other factors. In the Arctic however, the strength and direction of these effects have been difficult to detect and often vary widely among tundra types. In the coastal tundra near Barrow Alaska, fluctuations of lemming populations have long intrigued researchers and exclosure treatments were established at various periods between the 1950’s (Naval Arctic Research Laboratory) and early 1970’s (International Biological Program). Approximately 25% of these exclosures and control plots remain intact and were resampled in 2002 and 2010. The plots provide one of the few opportunities to assess how arctic tundra might be structured and function in the absence of herbivores. Plant cover and abundance as well as biomass estimates indicated that herbivores have had varied effects among soil moisture regimes. While herbivore exclusion resulted in a decrease in vascular plant abundance and diversity in all communities, dryer sites became lichen dominated and wetter sites became moss dominant. Additionally between resampling dates, these patterns have intensified as control plot graminoid biomass has increased in wetter sites while deciduous shrub biomass has increased slightly in dryer site control plots. Exclusion also resulted in differences in functional characteristics as well. Generally across all moisture regimes, exclusion increased albedo and decreased active layer, NDVI (normalized difference vegetation index), and CO2 uptake. Drier sites showed little difference in CH4 efflux, while moist and wet sites showed significant decreases in CH4 efflux in the absence of herbivores. These results suggest that herbivores have a strong effect on ecosystem structure and function in this coastal tundra and effects have become more pronounced recently. Because theoretical

  5. Chemical analyses of ground water for saline-water resources studies in Texas Coastal Plain stored in National Water Data Storage and Retrieval System

    USGS Publications Warehouse

    Taylor, R.E.

    1975-01-01

    Chemical analyses of 4,269 water samples from wells in 66 counties in Texas have been processed into the National Water Data Storage and Retrieval System by the Gulf Coast Hydrogeology Project of the U. S. Geological Survey. More than 65,000 chemical analyses of saline waters produced by oil test and production wells have been contributed to the project by major oil companies. The computerized tabulation and the computer-drawn map of the locations of sampling sites are the initial release of oil company, State, and Federal data in Texas Coastal Plain from the data bank.

  6. S. 684: Arctic Coastal Plain Competitive Oil and Gas Leasing Act. Introduced in the Senate of the United States, One Hundredth First Congress, First Session, March 29, 1989

    SciTech Connect

    Not Available

    1989-01-01

    S. 684 would authorize competitive oil and gas leasing and development to proceed on the Coastal Plain of the Arctic National Wildlife Refuge in a manner consistent with the protection of the environment, maintenance of fish and wildlife and their habitat, and the interests of the area's subsistence users; and to provide a new source of funding for: (1) the Land and Water Conservation Fund, (2) the preservation, protection, creation, enhancement, or restoration of wetlands, and (3) research, development, and commercialization of energy conservation and alternative sources.

  7. Documentation of model input and output values for the simulation of the ground-water flow system in the Cretaceous-age Coastal Plain aquifers of South Carolina

    USGS Publications Warehouse

    Campbell, B.G.; van Heeswijk, Marijke

    1996-01-01

    This report and the attached 3 1/2-inch diskette contain, in compressed format, the data sets for the model of ground-water flow in the Cretaceous-age Coastal Plain aquifers of South Carolina. The data sets can be uncompressed using a program provided with this report. The uncompressed files require approximately 3.7 megabytes of disk space on an IBM-compatible microcomputer1 using the MS-DOS operating system. All files are in American Standard Code for Information Interchange format.

  8. Paleoenvironmental interpretation of an ancient Arctic coastal plain: Integrated paleopedology and palynology from the Late Cretaceous (Maastrichtian) Prince Creek Formation, North Slope, Alaska, USA

    NASA Astrophysics Data System (ADS)

    McCarthy, P. J.; Flaig, P. P.; Fiorillo, A. R.

    2010-12-01

    The Cretaceous (Early Maastrichtian), dinosaur-bearing Prince Creek Formation, North Slope, Alaska, records high-latitude, alluvial sedimentation and soil formation on a low-lying, coastal plain during a greenhouse phase in Earth history. This study combines outcrop observations, micromorphology, geochemistry, and palynological analyses of paleosols in order to reconstruct local paleoenvironments of weakly developed, high-latitude coastal plain soils. Sediments of the Prince Creek Fm. include quartz- and chert-rich sandstone channels, and floodplains containing organic-rich siltstone and mudstone, carbonaceous shale, coal and ashfall deposits. Vertically stacked horizons of blocky-to-platy, drab-colored mudstone and siltstone with carbonaceous root-traces and mottled aggregates alternating with sandy units indicate that the development of compound and cumulative, weakly-developed soils on floodplains alternated with overbank alluviation and deposition on crevasse splay complexes on floodplains . Soil formation occurred on levees, point bars, crevasse splays and along the margins of floodplain lakes, ponds, and swamps. Soil-forming processes were interrupted by repeated deposition of sediment on top of soil profiles by flooding of nearby channels. Alluviation is evidenced by thin (<0.5 m) sand and silt horizons within soil profiles, along with common pedorelicts, papules, and fluctuations with depth in a variety of molecular ratios. Carbonaceous organic matter and root-traces, Fe-oxide depletion coatings, and zoned peds suggest periodic waterlogging, anoxia and gleying. In contrast, Fe-oxide mottles, ferruginous and manganiferous segregations, burrows, and rare illuvial clay coatings suggest recurring oxidation and periodic drying out of some soils. Jarosite mottles and halos, and rare pyrite and gypsum found in some distal paleosols implies a marine influence at the distal margins of the coastal plain. Biota including Peridinioid dinocysts, brackish and freshwater

  9. Evaluation of stream liming effects on water quality and spawning of migratory fishes in Maryland Coastal Plain streams. 1988 results. Final report

    SciTech Connect

    Greening, H.S.; Janicki, A.J.; Klauda, R.J.; Baudler, D.M.; Levin, D.M.

    1989-09-01

    Calcite dosers were tested in 1988 on three Maryland Coastal Plain streams subject to acidic pulses during precipitation events. Increased flow during precipitation events resulted in depressed pH, ANC and Ca concentrations and elevated A1 levels in untreated sections of each study stream. Water quality in areas of each stream receiving calcite slurry was maintained near baseflow conditions. In situ survival tests were performed on yellow perch and blueback herring. Adult spawning surveys, ichthyoplankton collections, and juvenile surveys showed several migratory fish populations to be near historically low levels in four of the five streams sampled in 1988.

  10. Evidence of Cold Climate Slope Processes from the New Jersey Coastal Plain: Debris Flow Stratigraphy at Haines Corner, Camden County, New Jersey

    USGS Publications Warehouse

    Newell, Wayne L.

    2005-01-01

    Excavations through surficial deposits across the New Jersey Coastal Plain commonly reveal homogenized surficial sediments, deformed sedimentary structures, chaotically rearranged bed-forms, and wedge-shaped cracks filled with sand from the top-most layers of extant soil profiles. As a whole, these abundant, broadly distributed phenomena are best explained as artifacts of an era of frozen ground during the last Pleistocene glacial maximum. Vigorous freeze-thaw processes and abundant seasonal rainfall created a landscape of low relief covered by highly mobile surficial deposits. The surficial deposits are at grade into broad, flat bottomed valleys now drained by small, tightly meandering, under-fit streams. Modern fluvial, aeolian, and slope processes are ineffectual in either creating or modifying these landscapes. One particularly brief exposure of complex slope deposits was documented at Haines Corner, Camden County, during the field work (1986) for the Surficial Geologic Map of southern and central New Jersey. The exposure, now presented and interpreted here, provides previously unavailable details of a system of freeze-thaw driven processes that unfolded upon a frozen, impermeable substrate 80 miles south of the southern margin of the Wisconsinan glacial advance to Long Island, N.Y. At the time of these extreme processes, the presently sub-aerial New Jersey Coastal Plain was not proximal to moderating effects of the Atlantic Ocean, being about 100 miles inland and 300 feet above the lowered sea level. Current studies of analogous deposits across the mid-Atlantic Coastal Plain now benefit from dating techniques that were not available during the geologic mapping field work (1985-'92). During the mapping in New Jersey, hundreds of exposures failed to produce datable carbon remains within the stratigraphy of the surficial deposits. Recently reported TL dates from wind-blown sand filling frost wedges, exposed elsewhere in New Jersey, indicate that the widely

  11. Detection of pharmaceuticals and other personal care products in groundwater beneath and adjacent to onsite wastewater treatment systems in a coastal plain shallow aquifer.

    PubMed

    Del Rosario, Katie L; Mitra, Siddhartha; Humphrey, Charles P; O'Driscoll, Michael A

    2014-07-15

    Onsite wastewater treatment systems (OWTS) are the predominant disposal method for human waste in areas without municipal sewage treatment alternatives. Relatively few studies have addressed the release of pharmaceuticals and personal care products (PPCPs) from OWTS to groundwater. PPCP fate and transport from OWTS are important, particularly where these systems are adjacent to sensitive aquatic ecosystems such as coastal areas or wetlands. The objectives of this study were to identify PPCPs in residential wastewater and groundwater beneath OWTS and to characterize the environmental conditions affecting the OWTS discharge of PPCPs to nearby streams. The study sites are in coastal plain aquifers, which may be considered vulnerable "end-members" for subsurface PPCP transport. The PPCPs most commonly detected in the OWTS, at concentrations ranging from 0.12 μg L(-1) to 12.04 μg L(-1) in the groundwater, included: caffeine, ibuprofen, DEET, and homosalate. Their presence was related to particulate and dissolved organic carbon abundance.

  12. Hydrologic, water-quality, and biological data for three water bodies, Texas Gulf Coastal Plain, 2000-2002

    USGS Publications Warehouse

    East, Jeffery W.; Hogan, Jennifer L.

    2003-01-01

    During July 2000?September 2002, the U.S. Geological Survey collected and analyzed site-specific hydrologic, water-quality, and biological data in Dickinson Bayou, Armand Bayou, and the San Bernard River in the Gulf Coastal Plain of Texas. Segments of the three water bodies are on the State 303(d) list. Continuous monitoring showed that seasonal variations in water temperature, specific conductance, pH, and dissolved oxygen in all three water bodies were similar to those observed at U.S. Geological Survey stations along the Texas Gulf Coast. In particular, water temperature and dissolved oxygen are inversely related. Periods of smallest dissolved oxygen concentrations generally occurred in the summer months when water temperatures were highest. Water-quality monitors were deployed at three depths in Dickinson Bayou. For periodically collected nutrients, the median concentration of ammonia nitrogen was largest in Dickinson Bayou and smallest in the San Bernard River. Median concentrations of ammonia plus organic nitrogen, nitrite plus nitrate nitrogen, and orthophosphorus were largest in Armand Bayou. The median concentration of each of the four nutrients was larger for high-flow samples than for low-flow samples. The largest individual nutrient concentrations occurred during spring and summer. Both median and individual concentrations of chlorophyll-a were largest for Armand Bayou; median concentrations of pheophyton were similar for all three water bodies, and individual concentrations were largest for Armand Bayou. Median densities of fecal coliform bacteria and E. coli bacteria were similar for all three water bodies. Flow conditions had minimal effect on concentrations of chlorophyll-a and pheophytin, but the largest bacteria densities were in samples collected during high flow. Yields of most nutrients tended to increase with distance downstream. Yields in the San Bernard River and tributaries were less than yields in Dickinson and Armand Bayous. For Dickinson

  13. Simulation of ground-water flow in aquifers in Cretaceous rocks in the central Coastal Plain, North Carolina

    USGS Publications Warehouse

    Eimers, J.L.; Lyke, W.L.; Brockman, A.R.

    1990-01-01

    The principal sources of water-supply in Cretaceous rocks in the central Coastal Plain of North Carolina are the Peedee, Black Creek, and upper Cape Fear aquifers. Ground-water withdrawals from these aquifers have increased from about 0.25 million gallons per day in 1910 to over 29 million gallons per day in 1986, causing water-level declines as much as 160 feet. The maximum rate of water-level decline in 1986 is about 11 feet per year in the Black Creek aquifer. A quasi-three dimensional ground-water flow model was constructed and calibrated for the period 1900 to 1986 to simulate past water-level declines and to estimate the effects of future pumpage. Comparisons of 1,867 observed and model-computed heads were made at 323 well sites. The average difference between computed and observed water levels is -1 foot. About 68 percent of all the differences between computed and observed water levels falls in the range from -21.0 to 21.0 feet. Simulation indicates that the 29 million gallons per day of pumpage in 1986 was supplied by (1) increased recharge (net discharge of 2 million gallons per day in 1900 changed to net recharge of 18 million gallons per day in 1986), (2) increased lateral inflow to the aquifers of about 8 million gallons per day, and (3) depletion of ground-water storage of about 1 million gallons per day. Two pumping scenarios simulated head changes through 1991 and were based on (1) constant pumpage at the 1986 rates in each aquifer, and (2) continuing increases in pumping rates from 1986 through 1991 and rates varying from 10 to 19 percent per year for the three pumped aquifers. For scenario 1, water-level declines exceeded 5 feet locally; however, water-level rises of about 1 foot occurred in two areas. For scenario 2, water-level declines ranged from 1 foot to 30 feet in some pumping centers.

  14. Long-term patterns of fruit production in five forest types of the South Carolina upper coastal plain.

    SciTech Connect

    Greenberg, Cathryn H.; Levey, Douglas J.; Kwit, Charles; McCarty, John P.; Pearson, Scott F.; Sargent, Sarah; Kilgo, John

    2012-02-06

    ABSTRACT Fleshy fruit is a key food resource for many vertebrates and may be particularly important energy source to birds during fall migration and winter. Hence, land managers should know how fruit availability varies among forest types, seasons, and years. We quantified fleshy fruit abundance monthly for 9 years (1995-2003) in 56 0.1-ha plots in 5 forest types of South Carolina's upper Coastal Plain, USA. Forest types were mature upland hardwood and bottomland hardwood forest, mature closed-canopy loblolly (Pinus taeda) and longleaf pine (P. palustris) plantation, and recent clearcut regeneration harvests planted with longleaf pine seedlings. Mean annual number of fruits and dry fruit pulp mass were highest in regeneration harvests (264,592 _ 37,444 fruits; 12,009 _ 2,392 g/ha), upland hardwoods (60,769 _ 7,667 fruits; 5,079 _ 529 g/ha), and bottomland hardwoods (65,614 _ 8,351 fruits; 4,621 _ 677 g/ha), and lowest in longleaf pine (44,104 _ 8,301 fruits; 4,102 _ 877 g/ha) and loblolly (39,532 _ 5,034 fruits; 3,261 _ 492 g/ha) plantations. Fruit production was initially high in regeneration harvests and declined with stand development and canopy closure (1995-2003). Fruit availability was highest June-September and lowest in April. More species of fruit-producing plants occurred in upland hardwoods, bottomland hardwoods, and regeneration harvests than in loblolly and longleaf pine plantations. Several species produced fruit only in 1 or 2 forest types. In sum, fruit availability varied temporally and spatially because of differences in species composition among forest types and age classes, patchy distributions of fruiting plants both within and among forest types, fruiting phenology, high inter-annual variation in fruit crop size by some dominant fruit-producing species, and the dynamic process of disturbance-adapted species colonization and decline, or recovery in recently harvested stands. Land managers could enhance fruit availability for wildlife by

  15. Aquifer geochemistry at potential aquifer storage and recovery sites in coastal plain aquifers in the New York city area, USA

    USGS Publications Warehouse

    Brown, C.J.; Misut, P.E.

    2010-01-01

    The effects of injecting oxic water from the New York city (NYC) drinking-water supply and distribution system into a nearby anoxic coastal plain aquifer for later recovery during periods of water shortage (aquifer storage and recovery, or ASR) were simulated by a 3-dimensional, reactive-solute transport model. The Cretaceous aquifer system in the NYC area of New York and New Jersey, USA contains pyrite, goethite, locally occurring siderite, lignite, and locally varying amounts of dissolved Fe and salinity. Sediment from cores drilled on Staten Island and western Long Island had high extractable concentrations of Fe, Mn, and acid volatile sulfides (AVS) plus chromium-reducible sulfides (CRS) and low concentrations of As, Pb, Cd, Cr, Cu and U. Similarly, water samples from the Lloyd aquifer (Cretaceous) in western Long Island generally contained high concentrations of Fe and Mn and low concentrations of other trace elements such as As, Pb, Cd, Cr, Cu and U, all of which were below US Environmental Protection Agency (USEPA) and NY maximum contaminant levels (MCLs). In such aquifer settings, ASR operations can be complicated by the oxidative dissolution of pyrite, low pH, and high concentrations of dissolved Fe in extracted water.The simulated injection of buffered, oxic city water into a hypothetical ASR well increased the hydraulic head at the well, displaced the ambient groundwater, and formed a spheroid of injected water with lower concentrations of Fe, Mn and major ions in water surrounding the ASR well, than in ambient water. Both the dissolved O2 concentrations and the pH of water near the well generally increased in magnitude during the simulated 5-a injection phase. The resultant oxidation of Fe2+ and attendant precipitation of goethite during injection provided a substrate for sorption of dissolved Fe during the 8-a extraction phase. The baseline scenario with a low (0.001M) concentration of pyrite in aquifer sediments, indicated that nearly 190% more water

  16. The Influence of Land Subsidence, Quarrying, Drainage, Irrigation and Forest Fire on Groundwater Resources and Biodiversity Along the Southern Po Plain Coastal Zone (Italy)

    NASA Astrophysics Data System (ADS)

    Antonellini, M. A.; Mollema, P. N.

    2014-12-01

    The coastal zone of the southern Po plain is characterized by low lying land, which is reclaimed to permit settlements and agriculture. The history, tourism resorts and peculiar coastal environments make this territory attractive and valuable. Natural and fluid-extraction-induced land subsidence along with coastal erosion are major problems. Touristic development has strongly modified the landscape; coastal dunes have been in part removed to make room for hotels and quarrying has caused the formation of gravel pit lakes close to the shoreline. Protected natural areas include a belt of coastal dunes, wetlands, and the internal historical forests of San Vitale and Classe. The dunes have largely lost their original vegetation ecosystem, because years ago they have been colonized with pine trees to protect the adjacent farmland from sea spray. These pine forests are currently a fire hazard. Land reclamation drainage keeps the water table artificially low. Results of these anthropogenic disturbances on the hydrology include a decrease in infiltration rates, loss of freshwater surface bodies, encroachment of saltwater inland from the river estuaries, salinization of the aquifer, wetlands and soil with a loss in plant and aquatic species biodiversity. Feedback mechanisms are complex: as land subsidence continues, drainage increases at the same pace promoting sea-water intrusion. The salinity of the groundwater does not allow for plant species richness nor for the survival of large pine trees. Farmland irrigation and fires in the pine forests, on the other hand, allow for increased infiltration and freshening of the aquifer and at the same time promote plant species diversity. Our work shows that the characteristics of the southern Po coastal zone require integrated management of economic activities, natural areas, and resources. This approach is different from the ad hoc measures taken so far, because it requires long term planning and setting a priority of objectives.

  17. Women and Minorities in Alaskan Aviation. Alaskan Equity Publication.

    ERIC Educational Resources Information Center

    Dordan, Mary Lou; Nicholson, Deborah

    This resource guide tells the story of Alaskan women and minority aviators and those in aviation-related businesses, from the early 20th century to the present. Developed for secondary students but also suitable for younger students, the guide combines six accounts of Alaskan women and minority aviators with classroom activities centered around…

  18. The role of dunes in contrasting saltwater intrusion in coastal areas; a case study in the southern Po Plain Adriatic coast (Ravenna, Northern Italy)

    NASA Astrophysics Data System (ADS)

    Marconi, V.; Antonellini, M.; Balugani, E.; Minchio, A.; Gabbianelli, G.

    2009-04-01

    Due to climate changes and to anthropogenic interventions, saltwater intrusion is affecting the aquifers and the surface water of the Po plain along the Adriatic coast. During the last decade, we recognized in this area a pattern of climate change: precipitations are less frequent and the yearly amount of rain is concentrated in a few strong storm events. This pattern results in an increase of gales strength during the winter, which causes shoreline retreat and an erosion of the coastal dunes. The coastal part of the Po plain consists of a low-lying and mechanically-drained farmland further from the sea and of a narrow belt of dunes and pine forests in the backshore area. The wide sandy beaches are now retreating and the dune system (only a few meters in height) is almoust destroyed, because of tourism development and of disaggregated rivers and shorelines management. A still active dune system is preserved in our study area, a coastal plain included between the Fiumi Uniti and Bevano rivers near the city of Ravenna. As a result of an intensive exploitation of coastal aquifers for agricultural, industrial, and civil uses, both the phreatic aquifer and the surface waters have been contaminated by seawater. Despite its value for the natural ecosystem and the agricultural soil, the phreatic aquifer is not considered of interest by the regional authorities responsible for water management. A detailed hydrogeological survey was performed by our research group during the Summer 2008 within the framework of the CIRCLE-ERANET project WATERKNOW on the effects of climate change on the mediterranean catchments. In this survey 29 auger holes with an average spacing of 350 m where drilled with the objective of determining the top groundwater quality in the coastal aquifer. At the same time, we measured the chemical and physical parameters of the surface waters. The data collected in the field show that a fresh groundwater lens is still present in the aquifer of the backshore

  19. SEASAT economic assessment. Volume 5: Coastal zones case study and generalization. [economic benefits of weather forecasting by SEASAT satellites to the coastal plains of the United States

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The economic losses sustained in the U.S. coastal zones were studied for the purpose of quantitatively establishing economic benefits as a consequence of improving the predictive quality of destructive phenomena in U.S. coastal zones. Improved prediction of hurricane landfall and improved experimental knowledge of hurricane seeding are discussed.

  20. Digital surfaces and hydrogeologic data for the Mesozoic through early Tertiary rocks in the Southeastern Coastal Plain in parts of Mississippi, Alabama, Georgia, South Carolina, and Florida

    USGS Publications Warehouse

    Cannon, Debra M.; Bellino, Jason C.; Williams, Lester J.

    2012-01-01

    A digital dataset of hydrogeologic data for Mesozoic through early Tertiary rocks in the Southeastern Coastal Plain was developed using data from five U.S. Geological Survey (USGS) reports published between 1951 and 1996. These reports contain maps and data depicting the extent and elevation of the Southeast Coastal Plain stratigraphic and hydrogeologic units in Florida and parts of Mississippi, Alabama, Georgia, and South Carolina. The reports are: Professional Paper 1410-B (Renken, 1996), Professional Paper 1088 (Brown and others, 1979), Professional Paper 524-G (Applin and Applin, 1967), Professional Paper 447 (Applin and Applin, 1965), and Circular 91 (Applin, 1951). The digital dataset provides hydrogeologic data for the USGS Energy Resources Program assessment of potential reservoirs for carbon sequestration and for the USGS Groundwater Resource Program assessment of saline aquifers in the southeastern United States. A Geographic Information System (ArcGIS 9.3.1) was used to construct 33 digital (raster) surfaces representing the top or base of key stratigraphic and hydrogeologic units. In addition, the Geographic Information System was used to generate 102 geo-referenced scanned maps from the five reports and a geo-database containing structural and thickness contours, faults, extent polygons, and common features. The dataset also includes point data of well construction and stratigraphic elevations and scanned images of two geologic cross sections and a nomenclature chart.

  1. Assessment of undiscovered oil and gas resources of the East Coast Mesozoic basins of the Piedmont, Blue Ridge Thrust Belt, Atlantic Coastal Plain, and New England Provinces, 2011

    USGS Publications Warehouse

    Milici, Robert C.; Coleman, James L.; Rowan, Elisabeth L.; Cook, Troy A.; Charpentier, Ronald R.; Kirschbaum, Mark A.; Klett, Timothy R.; Pollastro, Richard M.; Schenk, Christopher J.

    2012-01-01

    During the early opening of the Atlantic Ocean in the Mesozoic Era, numerous extensional basins formed along the eastern margin of the North American continent from Florida northward to New England and parts of adjacent Canada. The basins extend generally from the offshore Atlantic continental margin westward beneath the Atlantic Coastal Plain to the Appalachian Mountains. Using a geology-based assessment method, the U.S. Geological Survey estimated a mean undiscovered natural gas resource of 3,860 billion cubic feet and a mean undiscovered natural gas liquids resource of 135 million barrels in continuous accumulations within five of the East Coast Mesozoic basins: the Deep River, Dan River-Danville, and Richmond basins, which are within the Piedmont Province of North Carolina and Virginia; the Taylorsville basin, which is almost entirely within the Atlantic Coastal Plain Province of Virginia and Maryland; and the southern part of the Newark basin (herein referred to as the South Newark basin), which is within the Blue Ridge Thrust Belt Province of New Jersey. The provinces, which contain these extensional basins, extend across parts of Georgia, South Carolina, North Carolina, Virginia, Maryland, Delaware, Pennsylvania, New Jersey, New York, Connecticut, and Massachusetts.

  2. Summary of northern Atlantic coastal plain hydrology and its relation to disposal of high-level radioactive waste in buried crystalline rock; a preliminary appraisal

    USGS Publications Warehouse

    Lloyd, O.B.; Larson, J.D.; Davis, R.W.

    1985-01-01

    Interpretation of available hydrologic data suggests that some areas beneath the Coastal Plain in the States of Delaware, Maryland, New Jersey, North Carolina, and Virginia might have some potential for the disposal of nuclear waste in crystalline rock that is buried beneath the Coastal Plain sediments. The areas of major interest occur where the top of the basement rock lies between 1,000 and 4,000 feet below sea level, the aquifer(s) immediately above the basement rock are saturated with saline water, confining material overlies the saline water bearing aquifer(s), and groundwater flow in the saline water aquifer(s) can be established. Preliminary data on (1) the distribution and thickness of the lowermost aquifers and confining beds, (2) the distribution of hydraulic conductivity in the lowermost aquifers, (3) estimated hydraulic heads and inferred direction of lateral groundwater flow for 1980, and (4) the distribution of saline water and brine, indicate eastern parts of the study area relatively best meet most of the criteria proposed for sediments that would overlie any potential buried crystalline-rock disposal site.

  3. Relationships between acid deposition, watershed characteristics, and stream chemistry in Maryland's coastal plain. Final report. Volume 1. Text. Report for May 1984-June 1985

    SciTech Connect

    Campbell, S.; Bartoshesky, J.; Heimbuch, D.; Janicki, J.; Petrimoulx, H.

    1987-06-01

    Precipitation and stream-water chemistry data were collected from three watersheds in the Coastal Plain region of Maryland during the period May 1984 through June 1985 in an attempt to determine the potential effects of acidic deposition on the chemistry of these streams. The study streams included Lyons Creek, Morgan Creek, and Granny Finley Branch; these streams were chosen based on their differential responses to storm events observed in a survey of Coastal Plain streams in the spring of 1983. Lyons Creek typically exhibited lower pH, acid-neutralizing capacity, and concentrations of base cations than observed in the other streams. Sulfate mass balances suggest that the soils in the Lyons Creek watershed also have less affinity for sulfur retention than do soils of the other watersheds. Acidic pulses were observed in all three streams during the spring months; however, the magnitude of these pulses was less than that observed in 1983. Modeling of the relationships between precipitation chemistry, watershed interactions, and stream chemistry suggests that precipitation acidity can influence stream-water acidity, depending upon hydrological conditions and availabiility of acid-neutralizing materials in the watersheds.

  4. Arsenic in sediments, groundwater, and streamwater of a glauconitic Coastal Plain terrain, New Jersey, USA-Chemical " fingerprints" for geogenic and anthropogenic sources

    USGS Publications Warehouse

    Barringer, J.L.; Reilly, P.A.; Eberl, D.D.; Blum, A.E.; Bonin, J.L.; Rosman, R.; Hirst, B.; Alebus, M.; Cenno, K.; Gorska, M.

    2011-01-01

    Glauconite-bearing deposits are found worldwide, but As levels have been determined for relatively few. The As content of glauconites in sediments of the Inner Coastal Plain of New Jersey can exceed 100mg/kg, and total As concentrations (up to 5.95??g/L) found historically and recently in streamwaters exceed the State standard. In a major watershed of the Inner Coastal Plain, chemical " fingerprints" were developed for streambed sediments and groundwater to identify contributions of As to the watershed from geologic and anthropogenic sources. The fingerprint for streambed sediments, which included Be, Cr, Fe and V, indicated that As was predominantly of geologic origin. High concentrations of dissolved organic C, nutrients (and Cl-) in shallow groundwater indicated anthropogenic inputs that provided an environment where microbial activity released As from minerals to groundwater discharging to the stream. Particulates in streamwater during high flow constituted most of the As load; the chemical patterns for these particulates resembled the geologic fingerprint of the streambed sediments. The As/Cr ratio of these suspended particles likely indicates they derived not only from runoff, but from groundwater inputs, because As contributed by groundwater is sequestered on streambed sediments. Agricultural inputs of As were not clearly identified, although chemical characteristics of some sediments indicated vehicle-related inputs of metals. Sediment sampling during dry and wet years showed that, under differing hydrologic conditions, local anthropogenic fingerprints could be obscured but the geologic fingerprint, indicating glauconitic sediments as an As source, was robust. ?? 2011.

  5. The fault pattern in the northern Negev and southern Coastal Plain of Israel and its hydrogeological implications for groundwater flow in the Judea Group aquifer

    NASA Astrophysics Data System (ADS)

    Weinberger, G.; Rosenthal, E.

    1994-03-01

    On the basis of a broadly expanding data base, the hydrogeological properties of the Judea Group sequence in the northern Negev and southern Coastal Plain of Israel have been reassessed. The updated subsurface model is based on data derived from water- and oil-wells and on recent large-scale geophysical investigations. A new regional pattern of the reassessed geological through the subsurface of the study area has been revealed. In view of the reassessed geological and hydrological subsurface setting, it appears that the Judea Group aquifer should not be regarded as one continuous and undisturbed hydrological unit; owing to the occurrence of regional faults, its subaquifers are locally interconnected. These subaquifers, which contain mainly high-quality water, are juxtaposed, as a result of faulting, against Kurnub Group sandstones containing brackish paleowater. The latter Group is faulted against late Jurassic formations containing highly saline groundwater. In the Beer Sheva area, the Judea Group aquifer is vertically displaced against the Senonian and Eocene Mt. Scopus and Avdat Groups, which also contain brackish and saline water. In the southern Coastal Plain, major faults locally dissect also the Pleistocene Kurkar Group, facilitating inflow of Mg-rich groundwater deriving from Judea Group dolomites. The new geological evidence and its hydrogeological implications provide new solutions for previously unexplained salinization phenomena.

  6. History of ground-water pumpage and water-level decline in the Black Creek and upper Cape Fear aquifers of the central coastal plain of North Carolina

    USGS Publications Warehouse

    Winner, M.D.; Lyke, W.L.

    1986-01-01

    Historical ground-water withdrawals and a general water-level decline in the Black Creek and upper Cape Fear aquifers of the central Coastal Plain of North Carolina are documented. Total municipal and industrial pumpage from these aquifers has increased from approximately 120,000 gal/day (gpd) in 1910 to >21 million gpd in 1980. Major pumpage, > 10,000 gpd, began around 1900. Since that time, per capita water use in the central Coastal Plain area has ranged from 17 to 172 gpd/person. The higher values partially represent the increasing availability and use of modern conveniences since the World War II era. The range of per capita water use can be subdivided according to general water-use and population characteristics for both urban and rural areas. The pumpage of ground water from the Black Creek and upper Cape Fear aquifers has created water-level declines from 0.5 to 4.9 ft/year since 1900. Approximately a third of the study area has experienced a decline > 50 ft up to the period 1979-1981, with 148 ft being the maximum.

  7. Effects of urbanization on local winds and thermal environment in Nohbi Plain, coastal region of Central Japan - a numerical analysis by meso-scale meteorological model with k-{epsilon} turbulence model

    SciTech Connect

    Kitada, Toshihiro; Okamura, Kiyoshi; Tanaka, Setsu

    1996-12-31

    Japanese large cities, mostly located in coastal region, have rapidly expanded in the last three decades. People in the region now experience warmer and unpleasant thermal environment in summer season, supposedly because of the extensive urbanization. Especially, under fine weather with light synoptic-scale gradient wind, the highest temperature often appears in rather inland area. An explanation to this phenomenon is horizontal transport of heat by the sea breeze which is strongly heated during its passage over the coastal urban area. This study investigated how and how much urbanization in Nohbi Plain of central Japan influences local wind and temperature distribution over the plain and its surrounding region, Nohbi Plain which faces to the Pacific Ocean and is surrounded by the Japanese Alps, and thus is in a typical topographic situation in Japan. For the study we performed numerical simulations using our meso-scale meteorological model which includes k-c model for turbulence. One of the major results obtained is to have clarified a hierarchy in natural and artificial topography of various scales on their contributions to formation of characteristic diurnal pattern of wind and temperature distributions in the plain area. The Japanese Alps, the largest topographic feature in central Japan and often called the roof of Japan, gave the most important influence on the wind, although the mountains are located quite far, around 200 km, from Nohbi Plain. The way for the influence of the high mountains was to warm air mass in upper layer but below 2 km in altitude, over the Nohbi Plain through heat transport due to a large scale circulation consisting of the {open_quotes}flows from plain to plateau in lower layer and plateau to plain in upper layer{close_quotes}. Urbanization in the coastal Nohbi Plain showed little effect on the flow pattern, but caused large temperature rises at surface level in the inland area because of horizontal heat transfer by the sea breeze.

  8. Vegetation and climate development on the Atlantic Coastal Plain during the late Mid-Miocene Climatic Optimum (IODP Expedition 313)

    NASA Astrophysics Data System (ADS)

    Prader, Sabine; Kotthoff, Ulrich; McCarthy, Francine; Greenwood, David

    2015-04-01

    which was reminiscent of Oligocene and early Miocene ecosystems analyzed in previous studies (e.g. Kotthoff et al. 2014). The ecosystem was characterized by oak-hickory forests which probably dominated in the lowlands, while frequent occurrence of conifer pollen (Pinus, Picea, Abies, Sciadopitys, and Tsuga canadensis) indicate that conifer forests prevailed in higher altitudes during the MMCO. We assume that the Miocene uplift of the Appalachian Mountains (e.g. Gallen et al., 2013) led to the proliferation of mountainous taxa and thus to an increase of related pollen taxa in the palynological record. References: Gallen, S. F., Wegmann, K. W., Bohnenstieh, D. W. R.: Miocene rejuvenation of topographic relief in the southern Appalachians, GSA Today, 23, 4-10, 2013. Kotthoff, U., McCarthy, F.M.G., Greenwood, D.R., Müller-Navarra, K., Prader, S., Hesselbo, S.P., (2014): Vegetation and climate development on the Atlantic Coastal Plain from 33 to 13 million years ago (IODP expedition 313). Climate of the Past 10, 1523-1539.

  9. On the use of InSAR technology to assess land subsidence in Jakarta coastal flood plain

    NASA Astrophysics Data System (ADS)

    Koudogbo, Fifame; Duro, Javier; Garcia Robles, Javier; Arnaud, Alain; Abidin, Hasanuddin Z.

    2014-05-01

    Jakarta is the capital of Indonesia and is home to approximately 10 million people on the coast of the Java Sea. It is situated on the northern coastal alluvial plane of Java which shares boundaries with West Java Province in the south and in the east, and with Banten Province in the west. The Capital District of Jakarta (DKI) sits in the lowest lying areas of the basin. Its topography varies, with the northern part just meters above current sea level and lying on a flood plain. Subsequently, this portion of the city frequently floods. The southern part of the city is hilly. Thirteen major rivers flow through Jakarta to the Java Sea. The Ciliwung River is the most significant river and divides the city West to East. In the last three decades, urban growing of Jakarta has been very fast in sectors as industry, trade, transportation, real estate, among others. This exponential development has caused several environmental issues; land subsidence is one of them. Subsidence in Jakarta has been known since the early part of the 20th century. It is mainly due to groundwater extraction, the fast development (construction load), soil natural consolidation and tectonics. Evidence of land subsidence exists through monitoring with GPS, level surveys and InSAR investigations. InSAR states for "Interferometric Synthetic Aperture Radar". Its principle is based on comparing the distance between the satellite and the ground in consecutive satellite passes over the same area on the Earth's surface. Radar satellites images record, with very high precision, the distance travelled by the radar signal that is emitted by the satellite is registered. When this distance is compared through time, InSAR technology can provide highly accurate ground deformation measurements. ALTAMIRA INFORMATION, company specialized in ground motion monitoring, has developed GlobalSARTM, which combines several processing techniques and algorithms based on InSAR technology, to achieve ground motion

  10. Developing custom fire behavior fuel models from ecologically complex fuel structures for upper Atlantic Coastal Plain forests.

    SciTech Connect

    Parresol, Bernard, R.; Scott, Joe, H.; Andreu, Anne; Prichard, Susan; Kurth, Laurie

    2012-01-01

    Currently geospatial fire behavior analyses are performed with an array of fire behavior modeling systems such as FARSITE, FlamMap, and the Large Fire Simulation System. These systems currently require standard or customized surface fire behavior fuel models as inputs that are often assigned through remote sensing information. The ability to handle hundreds or thousands of measured surface fuelbeds representing the fine scale variation in fire behavior on the landscape is constrained in terms of creating compatible custom fire behavior fuel models. In this study, we demonstrate an objective method for taking ecologically complex fuelbeds from inventory observations and converting those into a set of custom fuel models that can be mapped to the original landscape. We use an original set of 629 fuel inventory plots measured on an 80,000 ha contiguous landscape in the upper Atlantic Coastal Plain of the southeastern United States. From models linking stand conditions to component fuel loads, we impute fuelbeds for over 6000 stands. These imputed fuelbeds were then converted to fire behavior parameters under extreme fuel moisture and wind conditions (97th percentile) using the fuel characteristic classification system (FCCS) to estimate surface fire rate of spread, surface fire flame length, shrub layer reaction intensity (heat load), non-woody layer reaction intensity, woody layer reaction intensity, and litter-lichen-moss layer reaction intensity. We performed hierarchical cluster analysis of the stands based on the values of the fire behavior parameters. The resulting 7 clusters were the basis for the development of 7 custom fire behavior fuel models from the cluster centroids that were calibrated against the FCCS point data for wind and fuel moisture. The latter process resulted in calibration against flame length as it was difficult to obtain a simultaneous calibration against both rate of spread and flame length. The clusters based on FCCS fire behavior

  11. Biogenic origin of coalbed gas in the northern Gulf of Mexico Coastal Plain, U.S.A

    USGS Publications Warehouse

    Warwick, P.D.; Breland, F.C.; Hackley, P.C.

    2008-01-01

    New coal-gas exploration and production in northern Louisiana and south-central Mississippi, Gulf of Mexico Basin, is focused on the Wilcox Group (Paleocene-Eocene), where the depth to targeted subbituminous C to high volatile C bituminous coal beds ranges from 300 to 1680??m, and individual coal beds have a maximum thickness of about 6??m. Total gas content (generally excluding residual gas) of the coal beds ranges from less than 0.37??cm3/g (as-analyzed or raw basis; 1.2??cm3/g, dry, ash free basis, daf) at depths less than 400??m, to greater than 7.3??cm3/g (as-analyzed basis; 8.76??cm3/g, daf) in deeper (> 1,500??m) parts of the basin. About 20 Wilcox coal-gas wells in northern Louisiana produce from 200 to 6485??m3 of gas/day and cumulative gas production from these wells is approximately 25??million m3 (as of December, 2006). U.S. Geological Survey assessment of undiscovered, technically recoverable gas resources in the Gulf of Mexico Coastal Plain, including northern and south-central Mississippi, indicates that coal beds of the Wilcox Group contain an estimated mean total 109.3??million m3 (3.86??trillion ft3) of producible natural gas. To determine the origin of the Wilcox Group coal gases in northern Louisiana, samples of gas, water, and oil were collected from Wilcox coal and sandstone reservoirs and from under- and overlying Late Cretaceous and Eocene carbonate and sandstone reservoirs. Isotopic data from Wilcox coal-gas samples have an average ??13CCH4 value of - 62.6??? VPDB (relative to Vienna Peedee Belemnite) and an average ??DCH4 value of - 199.9??? VSMOW (relative to Vienna Standard Mean Ocean Water). Values of ??13CCO2 range from - 25.4 to 3.42??? VPDB. Produced Wilcox saline water collected from oil, conventional gas, and coalbed gas wells have ??DH2O values that range from - 27.3 to - 18.0??? VSMOW. These data suggest that the coal gases primarily are generated in saline formation water by bacterial reduction of CO2. Shallow (< 150??m) Wilcox

  12. Age dating of shallow groundwater with chlorofluorocarbons, tritium/helium 3, and flow path analysis, southern New Jersey coastal plain

    USGS Publications Warehouse

    Szabo, Z.; Rice, D.E.; Plummer, L.N.; Busenberg, E.; Drenkard, S.; Schlosser, P.

    1996-01-01

    Groundwater age dating through the combination of transient tracer methods (chlorofluorocarbons (CFCs) and tritium/helium 3 (3H/3He)) and groundwater flow path analysis is useful for investigating groundwater travel times, flow patterns, and recharge rates, as demonstrated by this study of the homogeneous shallow, unconfined Kirkwood-Cohansey aquifer system in the southern New Jersey coastal plain. Water samples for age dating were collected from three sets of nested observation wells (10 wells) with 1.5-m-long screens located near groundwater divides. Three steady state finite difference groundwater flow models were calibrated by adjusting horizontal and vertical hydraulic conductivities to match measured heads and head differences (range, 0.002-0.23 m) among the nested wells, with a uniform recharge rate of 0.46 m per year and porosities of 0.35 (sand) and 0.45 (silt) that were assumed constant for all model simulations and travel time calculations. The simulated groundwater travel times increase with depth in the aquifer, ranging from about 1.5 to 6.5 years for the shallow wells (screen bottoms 3-4 m below the water table), from about 10 to 25 years for the medium-depth wells (screen bottoms 8-19 m below the water table), and from about 30 to more than 40 years for the deep wells (screen bottoms 24-26 m below the water table). Apparent groundwater ages based on CFC- and 3H/3He-dating techniques and model-based travel times could not be statistically differentiated, and all were strongly correlated with depth. Confinement of 3He was high because of the rapid vertical flow velocity (of the order of 1 m/yr), resulting in clear delineation of groundwater travel times based on the 3H/3He-dating technique. The correspondence between the 3H/3He and CFC ages indicates that dispersion has had a minimal effect on the tracer-based ages of water in this aquifer. Differences between the tracer-based apparent ages for seven of the 10 samples were smaller than the error values

  13. Alaskan Commodities Irradiation Project

    SciTech Connect

    Zarling, J.P.; Swanson, R.B.; Logan, R.R.; Das, D.K.; Lewis, C.E.; Workman, W.G.; Tumeo, M.A.; Hok, C.I.; Birklid, C.A.; Bennett, F.L.

    1988-12-01

    The ninety-ninth US Congress commissioned a six-state food irradiation research and development program to evaluate the commercial potential of this technology. Hawaii, Washington, Iowa, Oklahoma and Florida as well as Alaska have participated in the national program; various food products including fishery products, red meats, tropical and citrus fruits and vegetables have been studied. The purpose of the Alaskan study was to review and evaluate those factors related to the technical and economic feasibility of an irradiator in Alaska. This options analysis study will serve as a basis for determining the state's further involvement in the development of food irradiation technology. 40 refs., 50 figs., 53 tabs.

  14. The sea-level highstand correlated to marine isotope stage (MIS) 7 in the coastal plain of the state of Rio Grande do Sul, Brazil.

    PubMed

    Lopes, Renato P; Dillenburg, Sergio R; Schultz, Cesar L; Ferigolo, Jorge; Ribeiro, Ana Maria; Pereira, Jamil C; Holanda, Elizete C; Pitana, Vanessa G; Kerber, Leonardo

    2014-12-01

    The coastal plain of the state of Rio Grande do Sul, in southern Brazil, includes four barrier-lagoon depositional systems formed by successive Quaternary sea-level highstands that were correlated to marine isotope stages (MIS) 11, 9, 5 and 1, despite the scarcity of absolute ages. This study describes a sea-level highstand older than MIS 5, based on the stratigraphy, ages and fossils of the shallow marine facies found in coastal barrier (Barrier II). This facies outcrops along the banks of Chuí Creek, it is composed of fine, well-sorted quartz sand and contains ichnofossils Ophiomorpha nodosa and Rosselia sp., and molluscan shells. The sedimentary record indicates coastal aggradation followed by sea-level fall and progradation of the coastline. Thermoluminescence (TL) and electron spin resonance (ESR) ages from sediments and fossil shells point to an age of ∼220 ka for the end of this marine transgression, thus correlating it to MIS 7 (substage 7e). Altimetric data point to a maximum amplitude of about 10 meters above present-day mean sea-level, but tectonic processes may be involved. Paleoceanographic conditions at the time of the highstand and correlations with other deposits in the Brazilian coasts are also discussed.

  15. The sea-level highstand correlated to marine isotope stage (MIS) 7 in the coastal plain of the state of Rio Grande do Sul, Brazil.

    PubMed

    Lopes, Renato P; Dillenburg, Sergio R; Schultz, Cesar L; Ferigolo, Jorge; Ribeiro, Ana Maria; Pereira, Jamil C; Holanda, Elizete C; Pitana, Vanessa G; Kerber, Leonardo

    2014-12-09

    The coastal plain of the state of Rio Grande do Sul, in southern Brazil, includes four barrier-lagoon depositional systems formed by successive Quaternary sea-level highstands that were correlated to marine isotope stages (MIS) 11, 9, 5 and 1, despite the scarcity of absolute ages. This study describes a sea-level highstand older than MIS 5, based on the stratigraphy, ages and fossils of the shallow marine facies found in coastal barrier (Barrier II). This facies outcrops along the banks of Chuí Creek, it is composed of fine, well-sorted quartz sand and contains ichnofossils Ophiomorpha nodosa and Rosselia sp., and molluscan shells. The sedimentary record indicates coastal aggradation followed by sea-level fall and progradation of the coastline. Thermoluminescence (TL) and electron spin resonance (ESR) ages from sediments and fossil shells point to an age of ∼220 ka for the end of this marine transgression, thus correlating it to MIS 7 (substage 7e). Altimetric data point to a maximum amplitude of about 10 meters above present-day mean sea-level, but tectonic processes may be involved. Paleoceanographic conditions at the time of the highstand and correlations with other deposits in the Brazilian coasts are also discussed.

  16. Paleoclimatic modeling and phylogeography of least killifish, Heterandria formosa: insights into Pleistocene expansion-contraction dynamics and evolutionary history of North American Coastal Plain freshwater biota

    PubMed Central

    2013-01-01

    Background Climatic and sea-level fluctuations throughout the last Pleistocene glacial cycle (~130-0 ka) profoundly influenced present-day distributions and genetic diversity of Northern Hemisphere biotas by forcing range contractions in many species during the glacial advance and allowing expansion following glacial retreat ('expansion-contraction’ model). Evidence for such range dynamics and refugia in the unglaciated Gulf-Atlantic Coastal Plain stems largely from terrestrial species, and aquatic species Pleistocene responses remain relatively uninvestigated. Heterandria formosa, a wide-ranging regional endemic, presents an ideal system to test the expansion-contraction model within this biota. By integrating ecological niche modeling and phylogeography, we infer the Pleistocene history of this livebearing fish (Poeciliidae) and test for several predicted distributional and genetic effects of the last glaciation. Results Paleoclimatic models predicted range contraction to a single southwest Florida peninsula refugium during the Last Glacial Maximum, followed by northward expansion. We inferred spatial-population subdivision into four groups that reflect genetic barriers outside this refuge. Several other features of the genetic data were consistent with predictions derived from an expansion-contraction model: limited intraspecific divergence (e.g. mean mtDNA p-distance = 0.66%); a pattern of mtDNA diversity (mean Hd = 0.934; mean π = 0.007) consistent with rapid, recent population expansion; a lack of mtDNA isolation-by-distance; and clinal variation in allozyme diversity with higher diversity at lower latitudes near the predicted refugium. Statistical tests of mismatch distributions and coalescent simulations of the gene tree lent greater support to a scenario of post-glacial expansion and diversification from a single refugium than to any other model examined (e.g. multiple-refugia scenarios). Conclusions Congruent results from diverse data

  17. Relation of distribution of radium, nitrate, and pesticides to agricultural land use and depth, kirkwood-cohansey aquifer system, New Jersey coastal plain, 1990-91. Water-resources investigations

    SciTech Connect

    Szabo, Z.; Rice, D.E.; MacLeod, C.L.; Barringer, T.H.

    1997-12-31

    This report examines the relation of the distributions of dissolved radium, nitrate, and pesticides in the aquifer to the distribution of agricultural land and to depth in agricultural areas in the Coastal Plain of southern New Jersey. The report also discusses the geochemistry of the aquifer system and evaluates possible geochemical processes that result in the leaching of radium into solution.

  18. Field Observations of Erosion, Deposition, and Tsunami Flow Characteristics on the Sendai Coastal Plain after the March 2011, Tohoku-oki Tsunami, Japan

    NASA Astrophysics Data System (ADS)

    Richmond, B. M.; Goto, K.; Fujino, S.; Nishimura, Y.; Sugawara, D.; Tappin, D. R.; Witter, R. C.; Jaffe, B. E.; Chague-Goff, C.; Szczucinski, W.; Yulianto, E.; Goff, J. R.

    2011-12-01

    Case studies of recent tsunami impacts have proven to be extremely useful in understanding the geologic processes involved during tsunami inundation and return flow, and for the continued development of criteria to distinguish paleotsunami deposits in the geologic record. Here, we report on erosion, deposition, and flow characteristics of the March, 2011 Tohoku-oki Tsunami along a nearly 4.5 km shore-normal transect on the coastal plain near Sendai, Japan . The study area consists of a broad, low-relief prograding coastal plain which varies in a landward direction from: a) broad sand beach interrupted by shore-parallel engineering structures and backed by low (~3 m) sand dunes and a coastal forest; b) shore-parallel engineered drainage canal several meters deep and 10s of meters wide; c) rice fields marked by low-lying rectangular dyke systems and dotted with occasional buildings, canals, and roads; and d) elevated highway embankments which generally marked the landward extent of inundation except where gaps in the structure allowed inundation to occur further landward. Field observations focused on measurements of tsunami flow characteristics (height and direction), mapping of erosion features, and assessing sediment deposition based on shallow trenches at 50-100 m spacing, and sampling for sediment composition and geochemical analysis. Recorded tsunami inundation heights above mean sea level reached up to about 11 m above sea level within the first 500 m from the shoreline and then ranged between 3-5 m for the next 2 km gradually decreasing to about 3 m close to the inundation limit. The tsunami deposit generally thinned landward from an average maximum ~30 cm thick sand deposit in the coastal forest to a thin mud drape several mm thick near the inundation limit. A discontinuous sand-dominated sheet was prevalent to about 2800 m from the shoreline where mud content gradually increased further landward eventually resulting in a mud-dominated deposit up to about 3

  19. Arctic National Wildlife Refuge, Alaska, Coastal Plain Resource Assessment: Report and recommendation to the Congress of the United States and final legislative environmental impact statement

    USGS Publications Warehouse

    ,

    1987-01-01

    The Arctic National Wildlife Refuge, in the northeastern corner of Alaska, was first established as the Arctic National Wildlife Range by Public Land Order 2214 in 1960, for the purpose of preserving unique wildlife, wilderness, and recreational values. The original 8.9-millionacre Range was withdrawn from all forms of appropriation under the public land laws, including mining laws but not including mineral leasing laws. This order culminated extensive efforts begun more than a decade earlier to preserve this unique part of Alaska. The following report analyzes the potential environmental consequences of five management alternatives for the coastal plain, ranging from opening for lease of the entire area for oil and gas development, to wilderness designation. A legislative environmental impact statement has been integrated into the report.

  20. Microbial and Nutrient Concentration and Load Data During Stormwater Runoff at a Swine Concentrated Animal Feeding Operation in the North Carolina Coastal Plain, 2006-2007

    USGS Publications Warehouse

    Harden, Stephen L.

    2008-01-01

    This report summarizes water-quality and hydrologic data collected during 2006-2007 to characterize bacteria and nutrient loads associated with overland runoff and subsurface tile drainage in spray fields at a swine concentrated animal feeding operation. Four monitoring locations were established at the Lizzie Research Site in the North Carolina Coastal Plain Physiographic Province for collecting discharge and water-quality data during stormwater-runoff events. Water stage was measured continuously at each monitoring location. A stage-discharge relation was developed for each site and was used to compute instantaneous discharge values for collected samples. Water-quality samples were collected for five storm events during 2006-2007 for analysis of nutrients and fecal indicator bacteria. Instantaneous loads of nitrite plus nitrate, total coliform, Escherichia coli (E. coli), and enterococci were computed for selected times during the five storm events.

  1. Simulation of the Ground-Water Flow System in 1992, and Simulated Effects of Projected Ground-Water Withdrawals in 2020 in the New Jersey Coastal Plain

    USGS Publications Warehouse

    Gordon, Alison D.

    2003-01-01

    In 1992, ground-water withdrawals from the unconfined and confined aquifers in the New Jersey Coastal Plain totaled about 300 million gallons per day, and about 70 percent (200 million galllons per day) of this water was pumped from confined aquifers. The withdrawals have created large cones of depression in several Coastal Plain aquifers near populated areas, particularly in Camden and Ocean Counties. The continued decline of water levels in confined aquifers could cause saltwater intrusion, reduction of stream discharge near the outcrop areas of these aquifers, and depletion of the ground-water supply. Because of this, withdrawals from wells located within these critical areas have been reduced in the Potomac-Raritan-Magothy aquifer system, the Englishtown aquifer system, and the Wenonah-Mount Laurel aquifer. A computer-based model that simulates freshwater and saltwater flow was used to simulate transient ground-water flow conditions and the location of the freshwater-saltwater interface during 1989-92 in the New Jersey Coastal Plain. This simulation was used as the baseline for comparison of water levels and flow budgets. Four hypothetical withdrawal scenarios were simulated in which ground-water withdrawals were either increased or decreased. In scenario 1, withdrawals from wells located within critical area 2 in the Potomac-Raritan-Magothy aquifer system were reduced by amounts ranging from 0 to 35 percent of withdrawals prior to 1992. Critical area 2 is mainly located in Camden County, and most of Burlington and Gloucester Counties. With the reductions, water levels recovered about 30 feet in the regional cone of depression centered in Camden County in the Upper Potomac-Raritan-Magothy aquifer and by 20 ft in the Lower and Middle Potomac-Raritan-Magothy aquifers. In scenarios 2 to 4, withdrawals projected for 2020 were input to the model. In scenario 2, withdrawal restrictions within the critical areas were imposed in the Potomac-Raritan-Magothy aquifer

  2. Applications of Quaternary stratigraphic, soil-geomorphic, and quantitative geomorphic analyses to the evaluation of tectonic activity and landscape evolution in the Upper Coastal Plain, South Carolina

    SciTech Connect

    Hanson, K.L.; Bullard, T.F.; de Wit, M.W.; Stieve, A.L.

    1993-07-01

    Geomorphic analyses combined with mapping of fluvial terraces and upland geomorphic surfaces provide new approaches and data for evaluating the Quaternary activity of post-Cretaceous faults that are recognized in subsurface data at the Savannah River Site in the Upper Coastal Plain of southwestern South Carolina. Analyses of longitudinal stream and terrace profiles, regional slope maps, and drainage basin morphometry indicate long-term uplift and southeast tilt of the site region. Preliminary results of drainage basin characterization suggests an apparent rejuvenation of drainages along the trace of the Pen Branch fault (a Tertiary reactivated reverse fault that initiated as a basin-margin normal fault along the northern boundary of the Triassic Dunbarton Basin). This apparent rejuvenation of drainages may be the result of nontectonic geomorphic processes or local tectonic uplift and tilting within a framework of regional uplift.

  3. Climatic Variations In The Moisture and Instability Patterns Of The Atmospheric Boundary Layer On The East Mediterranean Coastal Plain Of Israel

    NASA Astrophysics Data System (ADS)

    Ben-Gai, T.; Bitan, A.; Manes, A.; Alpert, P.

    A long-term record (1964-1995) of radiosonde data observed atthe Bet-Dagan aerological station of the Israel Meteorological Service was analyzed to detect possible temporal trends in moisture content and instability of the atmospheric boundary layer. Bet-Dagan issituated in the central part of the south-east Mediterranean coastal plain. During this period surface characteristics in this region have changed drastically due to changes in land use, i.e., urbanization, development of irrigated agriculture and afforestation. The analysis of the radiosonde data reveals a clearly defined, statistically significant, increasing trend in the moisture content, mainly during summer. The stability of the surface layer, characterized by the bulk Richardson Number, shows adecreasing trend since the early 1960s. Relationships between these trends, land-use modifications and possible influence of large-scale influence are discussed.

  4. Evaluation of hot dry rock exploration techniques in the Atlantic Coastal Plain: a test site on the Delmarva Peninsula of Maryland and Virginia

    SciTech Connect

    Not Available

    1981-04-01

    Detailed investigation of a potential Hot Dry Rock (HDR) energy extraction site in the area of Crisfield, Maryland, and Wallops Island, Virginia, (referred to as the Cris-Wall site) was carried out to evaluate HDR exploration techniques in the Atlantic Coastal Plain province. The findings favor the HDR exploration program that is outlined for locating a deep test hole in an area with presumed HDR potential (higher than normal heat flow). Six potential sites for extracting HDR energy have been identified within the Cris-Wall area. Each site is thought to have temperatures at the basement rock surface in excess of 75/sup 0/C and to be at least 1 km away from the nearest fault.

  5. Comparison of amino acid racemization geochronometry with lithostratigraphy, biostratigraphy, uranium-series coral dating, and magnetostratigraphy in the Atlantic Coastal Plain of the southeastern United States

    USGS Publications Warehouse

    McCartan, L.; Owens, J.P.; Blackwelder, B. W.; Szabo, B. J.; Belknap, D.F.; Kriausakul, N.; Mitterer, R.M.; Wehmiller, J. F.

    1982-01-01

    The results of an integrated study comprising litho- and biostratigraphic investigations, uranium-series coral dating, amino acid racemization in molluscs, and paleomagnetic measurements are compared to ascertain relative and absolute ages of Pleistocene deposits of the Atlantic Coastal Plain in North and South Carolina. Four depositional events are inferred for South Carolina and two for North Carolina by all methods. The data suggest that there are four Pleistocene units containing corals that have been dated at about 100,000 yr, 200,000 yr, 450,000 yr, and over 1,000,000 yr. Some conflicts exist between the different methods regarding the correlation of the younger of these depositional events between Charleston and Myrtle Beach. Lack of good uranium-series dates for the younger material at Myrtle Beach makes the correlation with the deposits at Charleston more difficult. ?? 1982.

  6. Comparison of amino acid racemization geochronometry with lithostratigraphy, biostratigraphy, uranium-series coral dating, and magnetostratigraphy in the Atlantic Coastal Plain of the southeastern United States

    NASA Astrophysics Data System (ADS)

    McCartan, L.; Owens, J. P.; Blackwelder, B. W.; Szabo, B. J.; Belknap, D. F.; Kriausakul, N.; Mitterer, R. M.; Wehmiller, J. F.

    1982-11-01

    The results of an integrated study comprising litho- and biostratigraphic investigations, uranium-series coral dating, amino acid racemization in molluscs, and paleomagnetic measurements are compared to ascertain relative and absolute ages of Pleistocene deposits of the Atlantic Coastal Plain in North and South Carolina. Four depositional events are inferred for South Carolina and two for North Carolina by all methods. The data suggest that there are four Pleistocene units containing corals that have been dated at about 100,000 yr, 200,000 yr, 450,000 yr, and over 1,000,000 yr. Some conflicts exist between the different methods regarding the correlation of the younger of these depositional events between Charleston and Myrtle Beach. Lack of good uranium-series dates for the younger material at Myrtle Beach makes the correlation with the deposits at Charleston more difficult.

  7. Lithologic descriptions of two cores and ground-water-quality data from five counties in the northeastern part of the coastal plain of South Carolina, 1988 and 1991

    USGS Publications Warehouse

    Falls, W.F.

    1994-01-01

    This report presents data collected as part of a hydrologic investigation of Darlington, Dillon, Florence, Marion, and Marlboro Counties in the northeastern part of the Coastal Plain of South Carolina. These data include lithologic descriptions of sediment recovered from two continuously cored boreholes and water-quality results for samples collected from 17 existing wells. One continuously cored borehole was drilled near Lake Darpo in the northern part of Darlington County to a total depth of 447 feet below land surface. The other borehole was drilled in Lake City in the south-central part of Florence County to a total depth of 1,090 feet below land surface. Water-quality results presented in this report include specific conductance, dissolved oxygen, temperature, pH, alkalinity, major- and minor-ion chemistry, and hydrogen sulfide.

  8. /sup 40/Ar//sup 39/Ar age of detrital muscovite within Lower Ordovician sandstone in the coastal plain basement of Florida: implications for west African terrane linkages

    SciTech Connect

    Dallmeyer, R.D.

    1987-11-01

    Detrital muscovite was concentrated from a core of Lower Ordovician sandstone recovered from 1282 m in the Sun Oil Company, H.T. Parker No.1 well, Marion County, Florida. The concentrate records a /sup 40/Ar//sup 39/Ar plateau age of 504.1 +/- 2.1 Ma. The Paleozoic sedimentary section penetrated in this well is part of an extensive subsurface Lower Ordovician-Middle Devonian sedimentary succession characterized by Gondwanan paleontological affinities. The succession has been correlated with sequences of similar age in the Bove Basin of west Africa which unconformably overlie metamorphic units of the Bassaride and Rokelide orogens in Senegal and Guinea. Muscovite within these metamorphic rocks records ca. 500-510 Ma postmetamorphic /sup 40/Ar//sup 39/Ar cooling ages and was likely a proximal source for the lower Paleozoic clastic detritus represented in the pre-Mesozoic sedimentary sequences beneath the southeastern US coastal plain.

  9. Experimental assessment of factors mediating the naturalization of a globally invasive tree on sandy coastal plains: a case study from Brazil.

    PubMed

    Zimmermann, Thalita G; Andrade, Antonio C S; Richardson, David M

    2016-01-01

    As all naturalized species are potential invaders, it is important to better understand the determinants of naturalization of alien plants. This study sought to identify traits that enable the alien tree Casuarina equisetifolia to overcome barriers to survival and reproductive and to become naturalized on sandy coastal plains. Restinga vegetation in Brazil was used as a model system to conceptualize and quantify key stressors (high temperature, solar radiation, drought and salinity) which can limit the initial establishment of the plants. Experiments were conducted to evaluate the effects of these environmental factors on seed persistence in the soil (field), germination (laboratory), survival, growth, phenotypic plasticity and phenotypic integration (greenhouse). Results show that the expected viability of the seeds in the soil was 50 months. Seeds germinated in a similar way in constant and alternating temperatures (20-40 °C), except at 40 °C. Low light, and water and salt stresses reduced germination, but seeds recovered germination when stress diminished. Young plants did not tolerate water stress (<2 % of soil moisture) or deep shade. Growth was greater in sunny than in shady conditions. Although a low degree of phenotypic plasticity is important in habitats with multiple stress factors, this species exhibited high germination plasticity, although young plants showed low plasticity. The positive effect of phenotypic integration on plastic expression in the shade shows that in stressful environments traits that show greater phenotypic plasticity values may have significant phenotypic correlations with other characters, which is an important factor in the evolutionary ecology of this invasive species. Long-term seed persistence in the soil, broad germination requirements (temperature and light conditions) and the capacity to survive in a wide range of light intensity favours its naturalization. However, C. equisetifolia did not tolerate water stress and

  10. Influence of subaqueous shelf angle on coastal plain-shelf-slope deposits resulting from a rise or fall in base-level

    SciTech Connect

    Wood, L.J.; Ethridge, F.G.; Schumm, S.A. )

    1991-03-01

    Extensive research in the past decade concerning the effects of base-level fluctuations on coastal plain-shelf-slope systems along passive margins has failed to properly assess the influence of the subaqueous shelf angle on the development, character, and preservation of the resulting deposits. A series of experiments were performed in a 4 m by 7 m flume to examine the effect that differing shelf angles have on a simulated coastal plain-shelf-slope system undergoing a cycle of base-level rise and fall. Results of the experiments indicate that the angle of the shelf affects (1) the amount of sediment available for deposition, (2) the timing of the influx of drainage basin sediment into the lower portions of the fluvial system, and (3) the width to depth ratio and sinuosity of fluvial systems that develop on the shelf. Base-level fall over a steep shelf results in deep, narrow, straight fluvial channels on the shelf and fine-grained, thick shelf-margin deltas. Depositional systems show high sedimentation rates, but a low ratio of coarse-grained to fine-grained sediment. Multiple fluvial incisions on the shelf are rapidly abandoned for a single incised valley. In contrast, gentle shelf angles result in shallow, wide, meandering fluvial channels on the shelf and coarser-grained, thinner shelf-margin deltas. Depositional systems have a lower sedimentation rate, but a high ratio of coarse-grained to fine-grained sediment. Multiple fluvial incisions on the shelf are active for a longer period of time. During subsequent base-level rise, deposits have a low potential for preservation owing to their thin nature and the slower rate at which transgression occurs over the shelf.

  11. Edaphic and climatic effects on forest stand development, net primary production, and net ecosystem productivity simulated for Coastal Plain loblolly pine in Virginia

    NASA Astrophysics Data System (ADS)

    Sampson, D. A.; Wynne, R. H.; Seiler, J. R.

    2008-03-01

    We used SECRETS-3PG to simulate net primary production (NPP) and net ecosystem productivity (NEP) of loblolly pine (Pinus taeda L.) growing on the Virginia Coastal Plain, focusing on the effects of soils and climate, and stand age over a 30-year rotation. Soil type was influential, with heavier soils having greater NEP earlier in the rotation than lighter, sandier soils, although these differences disappeared by the rotation end. Climate had only a small effect. Stand age had the largest effect, with simulated annual NEP strongly negative during the first 5 to 8 years of development but peaking at +600 g C m-2 a-1 by age 13. Modest declines in NEP after 13 years were associated with declines in LAI as stands aged. The 30-year mean annual NEP was positive over most of the study area but in a few cases was indistinguishable from zero for northwestern portions of the study. Simulated annual NPP rose from zero to over 2300 g biomass m-2 a-1 by age 12, after which it declined to ˜1700 g biomass m-2 a-1 by rotation end. These results suggest that loblolly pine plantations on the Coastal Plain of Virginia may become net annual C sinks 5 to 9 years after planting but that when averaged over a whole rotation the net carbon accumulation during the baseline rotation simulated here is indistinguishable from zero. Our results also suggest, however, that this finding is sensitive to the length of the rotation, soil type (and thus fertility), and climate, implying that changes in management practices could significantly influence the carbon balance in managed loblolly pine plantations.

  12. Assessment of the impact of anthropogenic activities on the groundwater hydrology and chemistry in Tarsus coastal plain (Mersin, SE Turkey) using fuzzy clustering, multivariate statistics and GIS techniques

    NASA Astrophysics Data System (ADS)

    Güler, Cüneyt; Kurt, Mehmet Ali; Alpaslan, Musa; Akbulut, Can

    2012-01-01

    SummaryTarsus coastal plain (TCP) is an economically and ecologically important area situated in between the fertile fluvio-deltaic plains of two rivers, Deliçay and Tarsus (Mersin, SE Turkey), where anthropogenic activities (agricultural, industrial, and domestic) are very intense. Twenty-four water quality parameters were surveyed at 193 groundwater and 10 surface water sites during August 2008. The objective was to characterize the physico-chemical properties of groundwaters in TCP, assess the impact of anthropogenic activities on the groundwater hydrology and chemistry, and identify the major hydrogeochemical processes occurring in the area. Groundwater samples were grouped into hydrochemically distinct and spatially continuous four water classes (i.e., C1, C2, C3, and C4) using the fuzzy c-means (FCM) clustering method, where membership values were interpolated using the ordinary kriging technique. Principal components analysis (PCA) was used to decipher various underlying natural and anthropogenic processes creating these distinct water classes. Four principal components (PCs) were extracted in PCA which explained more than 73% of the total variance in water quality. Major factors responsible for the variations in chemistries of water classes are identified as: (1) water-rock interaction and nitrate contamination; (2) salinization by seawater intrusion and evaporite dissolution; (3) geogenic/anthropogenic Cr, Fe, and Mn; and (4) anthropogenic Zn pollution. Overexploitation of the aquifer is clearly evident, especially at settlements located near the coastal zone, where the water table is lowered 2-5 m below the sea level. Salinization is well known in the area and is attributed not only to seawater intrusion, but also to dissolution of evaporitic series from the Handere formation. Hydrochemical evidence also suggest that in the area subsurface paleo-river channels and the deposits infilling the ancient lagoon area within Quaternary-Recent alluvial deposits

  13. The contribution of Fe(III) and humic acid reduction to ecosystem respiration in drained thaw lake basins of the Arctic Coastal Plain

    NASA Astrophysics Data System (ADS)

    Lipson, David A.; Raab, Theodore K.; Goria, Dominic; Zlamal, Jaime

    2013-04-01

    research showed that anaerobic respiration using iron (Fe) oxides as terminal electron acceptor contributed substantially to ecosystem respiration (ER) in a drained thaw lake basin (DTLB) on the Arctic coastal plain. As DTLBs age, the surface organic layer thickens, progressively burying the Fe-rich mineral layers. We therefore hypothesized that Fe(III) availability and Fe reduction would decline with basin age. We studied four DTLBs across an age gradient, comparing seasonal changes in the oxidation state of dissolved and extractable Fe pools and the estimated contribution of Fe reduction to ER. The organic layer thickness did not strictly increase with age for these four sites, though soil Fe levels decreased with increasing organic layer thickness. However, there were surprisingly high levels of Fe minerals in organic layers, especially in the ancient basin where cryoturbation may have transported Fe upward through the profile. Net reduction of Fe oxides occurred in the latter half of the summer and contributed an estimated 40-45% to ecosystem respiration in the sites with the thickest organic layers and 61-63% in the sites with the thinnest organic layers. All sites had high concentrations of soluble Fe(II) and Fe(III), explained by the presence of siderophores, and this pool became progressively more reduced during the first half of the summer. Redox titrations with humic acid (HA) extracts and chelated Fe support our view that this pattern indicates the reduction of HA during this interval. We conclude that Fe(III) and HA reductions contribute broadly to ER in the Arctic coastal plain.

  14. Experimental assessment of factors mediating the naturalization of a globally invasive tree on sandy coastal plains: a case study from Brazil

    PubMed Central

    Zimmermann, Thalita G.; Andrade, Antonio C. S.; Richardson, David M.

    2016-01-01

    As all naturalized species are potential invaders, it is important to better understand the determinants of naturalization of alien plants. This study sought to identify traits that enable the alien tree Casuarina equisetifolia to overcome barriers to survival and reproductive and to become naturalized on sandy coastal plains. Restinga vegetation in Brazil was used as a model system to conceptualize and quantify key stressors (high temperature, solar radiation, drought and salinity) which can limit the initial establishment of the plants. Experiments were conducted to evaluate the effects of these environmental factors on seed persistence in the soil (field), germination (laboratory), survival, growth, phenotypic plasticity and phenotypic integration (greenhouse). Results show that the expected viability of the seeds in the soil was 50 months. Seeds germinated in a similar way in constant and alternating temperatures (20–40 °C), except at 40 °C. Low light, and water and salt stresses reduced germination, but seeds recovered germination when stress diminished. Young plants did not tolerate water stress (<2 % of soil moisture) or deep shade. Growth was greater in sunny than in shady conditions. Although a low degree of phenotypic plasticity is important in habitats with multiple stress factors, this species exhibited high germination plasticity, although young plants showed low plasticity. The positive effect of phenotypic integration on plastic expression in the shade shows that in stressful environments traits that show greater phenotypic plasticity values may have significant phenotypic correlations with other characters, which is an important factor in the evolutionary ecology of this invasive species. Long-term seed persistence in the soil, broad germination requirements (temperature and light conditions) and the capacity to survive in a wide range of light intensity favours its naturalization. However, C. equisetifolia did not tolerate water stress and

  15. Experimental assessment of factors mediating the naturalization of a globally invasive tree on sandy coastal plains: a case study from Brazil.

    PubMed

    Zimmermann, Thalita G; Andrade, Antonio C S; Richardson, David M

    2016-01-01

    As all naturalized species are potential invaders, it is important to better understand the determinants of naturalization of alien plants. This study sought to identify traits that enable the alien tree Casuarina equisetifolia to overcome barriers to survival and reproductive and to become naturalized on sandy coastal plains. Restinga vegetation in Brazil was used as a model system to conceptualize and quantify key stressors (high temperature, solar radiation, drought and salinity) which can limit the initial establishment of the plants. Experiments were conducted to evaluate the effects of these environmental factors on seed persistence in the soil (field), germination (laboratory), survival, growth, phenotypic plasticity and phenotypic integration (greenhouse). Results show that the expected viability of the seeds in the soil was 50 months. Seeds germinated in a similar way in constant and alternating temperatures (20-40 °C), except at 40 °C. Low light, and water and salt stresses reduced germination, but seeds recovered germination when stress diminished. Young plants did not tolerate water stress (<2 % of soil moisture) or deep shade. Growth was greater in sunny than in shady conditions. Although a low degree of phenotypic plasticity is important in habitats with multiple stress factors, this species exhibited high germination plasticity, although young plants showed low plasticity. The positive effect of phenotypic integration on plastic expression in the shade shows that in stressful environments traits that show greater phenotypic plasticity values may have significant phenotypic correlations with other characters, which is an important factor in the evolutionary ecology of this invasive species. Long-term seed persistence in the soil, broad germination requirements (temperature and light conditions) and the capacity to survive in a wide range of light intensity favours its naturalization. However, C. equisetifolia did not tolerate water stress and

  16. Modelling water-table depth in a primary aquifer to identify potential wetland hydrogeomorphic settings on the northern Maputaland Coastal Plain, KwaZulu-Natal, South Africa

    NASA Astrophysics Data System (ADS)

    Kelbe, Bruce E.; Grundling, Althea T.; Price, Jonathan S.

    2016-02-01

    The primary aquifer on the Maputaland Coastal Plain in northern KwaZulu-Natal, South Africa, is the principal source of water for rivers, lakes and most of the wetlands in dry periods, and is recharged by these systems in wet periods. Modelling hydrologic conditions that control regional water-table depth can provide insight into the spatial patterns of wetland occurrence and of the persistence of wet conditions that control their character. This project used a groundwater model (MODFLOW) to simulate 10-year water-table fluctuations on the Maputaland Coastal Plain from January 2000 to December 2010, to contrast the conditions between wet and dry years. Remote sensing imagery was used to map "permanent" and "temporary" wetlands in dry and wet years to evaluate the effectiveness of identifying the suitable conditions for their formation using numerical modelling techniques. The results confirm that topography plays an important role on a sub-regional and local level to support wetland formation. The wetlands' extent and distribution are directly associated with the spatial and temporal variations of the water table in relation to the topographical profile. Groundwater discharge zones in the lowland (1-50 masl) areas support more permanent wetlands with dominantly peat or high organic soil substrates, including swamp forest and most of the permanent open water areas. Most temporary wetlands associated with low-percentage clay occurrence are through-flow low-lying interdune systems characterised by regional fluctuation of the water table, while other temporary wetlands are perched or partially perched. The latter requires a more sophisticated saturated-unsaturated modelling approach.

  17. Estimating the Regional Flux of Nitrate and Agricultural Herbicide Compounds from Groundwater to Headwater Streams of the Northern Atlantic Coastal Plain, USA

    NASA Astrophysics Data System (ADS)

    Ator, S.; Denver, J. M.

    2011-12-01

    Agriculture is common in the Northern Atlantic Coastal Plain (NACP, including New Jersey through North Carolina), and groundwater discharge provides nitrogen (primarily in the form of nitrate) and herbicide compounds from agricultural sources along with the majority of flow to NACP streams. Poor water quality has contributed to ecological degradation of tidal streams and estuaries along much of the adjacent mid-Atlantic coast. Although statistical models have provided estimates of total instream nutrient flux in the Coastal Plain, the regional flux of nitrogen and herbicides during base flow is less well understood. We estimated the regional flux of nitrate and selected commonly used herbicide compounds from groundwater to non-tidal headwater streams of the NACP on the basis of late-winter or spring base-flow samples from 174 such streams. Sampled streams were selected using an unequal-probability random approach, and flux estimates are based on resulting population estimates rather than empirical models, which are commonly used for such estimates. Base-flow flux in the estimated 8,834 NACP non-tidal headwater streams are an estimated 21,200 kilograms per day of nitrate (as N) and 5.83, 0.565, and 20.7 kilograms per day of alachlor, atrazine, and metolachlor (including selected degradates), respectively. Base-flow flux of alachlor and metolachlor is dominated by degradates; flux of parent compounds is less than 3 percent of the total flux of parent plus degradates. Base-flow flux of nitrate and herbicides as a percentage of applications generally varies predictably with regional variations in hydrogeology. Abundant nonpoint (primarily agricultural) sources and hydrogeologic conditions, for example, contribute to particularly large base-flow flux from the Delmarva Peninsula to Chesapeake Bay. In the Delmarva Peninsula part of the Chesapeake Watershed, more than 10 percent of total nonpoint nitrogen applications is transported through groundwater to stream base flow

  18. Geohydrology and digital-simulation model of the Farrington aquifer in the northern coastal plain of New Jersey

    USGS Publications Warehouse

    Farlekas, George M.

    1979-01-01

    A two-dimensional digital-computer flow model was developed to simulate the Farrington aquifer in the northern part of the Coastal Plain of New Jersey. The area of detailed study includes approximately 500 square miles in Middlesex and Monmouth Couties where the aquifer provides a large part of the municipal and industrial water supply. The area modeled is much larger, extending seaward as well as northeastward into Long Island. The aquifer consists chiefly of the Farrington Sand Member of the Raritan Formation and is composed of sand and some gravel. It thickens from a featheredge in outcrop to more than 170 feet, 11 miles to the southeast. The confining unit between the Farrington and the overlying Old Bridge Sand Member of the Magothy Formation consists primarily of the Woodbridge Clay Member of the Raritan Formation and has a maximum thickness of 244 feet. The model simulates both water-table and artesian conditions. The confining unit overlying the Farrington aquifer is simulated as having a variable thickness and vertical hydraulic conductivity. The effect of a declining water level in the overlying Old Bridge aquifer on the Farrington aquifer is also simulated by the model. Values used to describe the hydraulic properties of the Farrington aquifer are: a hydraulic conductivity of 105 feet per day, a storage coefficient of 1.6 x 10-4 for artesian conditions, and a specific yield of 0.25 for water-table conditions. Values for the overlying confining unit are: a vertical hydraulic conductivity ranging from 4.2 x 10-7 to 1.0 x 10-10 feet per second and a specific storage of 4 x 10-5 feet-1. Aquifer simulation for the 15-year period, 1959-73, was used to calibrage the model. The model was calibrated by comparing the observed potentiometric surface of November 1973 with the simulated potentiometric surface. In addition, hydrographs for selected wells were compared with model results. Ground-water withdrawals for 1959 and 1973 were 12.1 and 28.5 milion gallons per

  19. Effectiveness of riparian buffers in controlling ground-water discharge of nitrate to streams in selected hydrogeologic settings of the North Carolina Coastal Plain

    USGS Publications Warehouse

    Spruill, T.B.

    2004-01-01

    Water-quality and hydrologic information were collected along ground-water flow paths from two well-drained and two poorly drained Coastal Plain settings in North Carolina to evaluate the relative effectiveness of riparian buffers in reducing discharge of nitrate to streams. At one well-drained site with a 100 m buffer, little or no effect was detected on surface-water quality by discharging ground water because extensive woody vegetation in the buffer was able to take up not only most nitrate, but also most ground water before discharging to the stream during the growing season (March-October). At the second well-drained site, ground water discharging to the stream from the side with a buffer contained about 2 mg/L of nitrate-nitrogen after passing through the bed of the stream compared to 6 mg/L in ground water discharging from the side with no buffer. In the poorly drained settings, nitrate in ground water decreased from about 6 mg/L in the recharge area to less than 0.02 mg/L downgradient from the riparian buffer. Ground water discharging from the side with no buffer contained 0.83 mg/L. Riparian buffers appear effective in reducing nitrate in ground water discharging to Coast Plain streams. ?? US Government 2004.

  20. Reconstructing conditions during dolomite formation on a Carnian coastal sabkha/alluvial plain using 87Sr/86Sr isotopes - Travenanzes Formation, northern Italy

    NASA Astrophysics Data System (ADS)

    Rieder, Maximilian; Wegner, Wencke; Horschinegg, Monika; Preto, Nereo; Breda, Anna; Klötzli, Urs; Peckmann, Jörn; Meister, Patrick

    2016-04-01

    The study of large amounts of dolomite that formed in the Triassic Tethyan realm is hampered by late diagenetic or hydrothermal overprint. These dolomites are difficult to link to past environmental and early diagenetic conditions, and their correlation to models for dolomite formation in modern environments is problematic. Preto et al. (2015) suggested, based on evidence from nano-scale structure analysis by transmission electron microscopy and petrographic observations, that dolomites in the Carnian Travenanzes Formation of the Southern Alps (Dolomites area) represent a preserved primary phase. The Travenanzes Formation was deposited in an extended alluvial plain or coastal sabkha environment subject to a semi-arid climate. Beds and nodules of nearly stoichiometric dolomite are embedded in large amounts of clay, which shielded early formed dolomite from diagenetic fluids. This finding of penecontemporaneous dolomite provides an ideal model case for reconstructing past environmental conditions at the time of dolomite precipitation. While Preto et al. (2015) argued that dolomite formation was mediated by extracellular polymeric substances produced by sulphate-reducing bacteria, it remains unclear whether precipitation occurred from evaporating seawater or mainly from brine derived from evaporating continental groundwater. Both cases exist in modern environments of dolomite formation. In the coastal sabkhas of Abu Dhabi and Qatar, dolomite precipitates from concentrated brine derived from seawater, either through seepage and reflux or through evaporative pumping (the sabkha model). In the coastal ephemeral lakes of the Coorong Lagoon system (South Australia) dolomite precipitation occurs from evaporating groundwater. The goal of this study is to distinguish marine from continental influence during formation of Carnian dolomite using 87Sr/86Sr isotope ratios. Sr isotopes could reveal different origins of ionic solutions for dolomite precipitation, which is not

  1. An Alaskan legend

    USGS Publications Warehouse

    Mann, H.; Blodgett, R.B.

    2009-01-01

    Jack Lee is a prominent personality, an Alaskan individualist and a skeptic worthy of remembrance if for no other reason than being inextricably associated with the catastrophic Katmai eruption in 1912. Jack remains a provocative reminder of Alaska's pre-1958 drilling and was quite possibly the earliest observer (excepting natives and possibly Russians) of the oil seeps in the area now encompassed by the Becharof National Wildlife Refuge. His observation of the impressive live oil seeps in the Ugashik and Becharof Lakes area, and his subsequent involvement in the early drilling entirely consumed his future interests. He is a firm believer that individualism and suspicion are powerful tools when forced to reconsider alternatives to readily accepted interpretations of modern exploration results. His individualism and sometimes annoying, but thought-provoking skepticism remains useful in any field where clich??s provide safe guards from new concepts.

  2. Rescuing degrading aquifers in the Central Coastal Plain of North Carolina (USA): Just process, effective groundwater management policy, and sustainable aquifers

    NASA Astrophysics Data System (ADS)

    Manda, Alex K.; Klein, Wendy A.

    2014-07-01

    Strategic management of degrading coastal aquifers in eastern North Carolina (USA) became imperative after a severe imbalance occurred between withdrawal and recharge rates. To ameliorate this growing problem, an aggressive water policy was developed through public input by creating the Central Coastal Plain Capacity Use Area (CCPCUA) to maintain beneficial use of groundwater resources. Insights from social psychology, and socio-legal studies are used to evaluate how procedural justice and public participation played major roles to resolving groundwater resource management problems. A mixed methods approach uses archival data and interviews with various rule-making participants to assess the process of stakeholder involvement that led to creation of the policy. In addition, data analysis techniques are utilized to evaluate the effects of the policy on aquifer health (through water levels) over a ˜10 year period. Results suggest that not only did a stakeholder group participate in a process that was deemed fair, understandable, and relatively easy to administer for users and regulators, but public participation resulted in an effective plan that ensures the long-term sustainable use of groundwater. Declining groundwater withdrawals and recovering water levels suggest that the rule is achieving its intended goal of protecting the aquifers from depletion and degradation. This paper touches on global themes that are essential to water demand and consumption, water management techniques, and water resources protection.

  3. Old groundwater in parts of the upper Patapsco aquifer,Atlantic Coastal Plain, Maryland, USA: Evidence fromradiocarbon, chlorine-36 and helium-4

    USGS Publications Warehouse

    Plummer, L. Niel; Eggleston, John R.; Raffensperger, Jeff P.; Hunt, Andrew G.; Casile, Gerolamo C.; Andreasen, D.C.

    2012-01-01

    Apparent groundwater ages along two flow paths in the upper Patapsco aquifer of the Maryland Atlantic Coastal Plain, USA, were estimated using 14C, 36Cl and 4He data. Most of the ages range from modern to about 500 ka, with one sample at 117 km downgradient from the recharge area dated by radiogenic 4He accumulation at more than one Ma. Last Glacial Maximum (LGM) water was located about 20 km downgradient on the northern flow path where the radiocarbon age was 21.5 ka, paleorecharge temperatures were 0.5 to 1.5 °C (a maximum cooling of about 12 °C relative to the modern mean annual temperature of 13 °C), and Cl-, Cl/Br, and stable isotopes of water were minimum. Low recharge temperatures (typically 5-7 °C) indicate that recharge occurred predominantly during glacial periods when coastal heads were lowest due to low sea-level stand. Flow velocities averaged about 1.0 ma-1 in upgradient parts of the upper Patapsco aquifer and decreased from 0.13 ma-1 to 0.04 ma-1 at 40 km and 80 km further downgradient, respectively. This study demonstrates that most water in the upper Patapsco aquifer is non-renewable on human timescales under natural gradients, thus highlighting the importance of effective water-supply management to prolong the resource.

  4. Coastal Prairie

    USGS Publications Warehouse

    ,

    2000-01-01

    The coastal prairie, located along the coastal plain of southwestern Louisiana and southcentral Texas, is the southernmost tip of the tallgrass prairie ecosystem so prevalent in the Midwest. The coastal prairie ecosystem once covered as much as 3.8 million ha (9 million acres); today, more than 99% of this land has been lost to agriculture, range improvement, and urbanization. The remainder is highly fragmented and severely threatened by invasions of exotic species and urban sprawl. In Louisiana, the former 1 million ha of coastal prairie have now been reduced to about 100 ha. In Texas, only about 100,000 ha of coastal prairie remain intact.

  5. Erosion, deposition and landscape change on the Sendai coastal plain, Japan, resulting from the March 11, 2011 Tohoku-oki tsunami

    NASA Astrophysics Data System (ADS)

    Richmond, Bruce; Szczuciński, Witold; Chagué-Goff, Catherine; Goto, Kazuhisa; Sugawara, Daisuke; Witter, Rob; Tappin, David R.; Jaffe, Bruce; Fujino, Shigehiro; Nishimura, Yuichi; Goff, James

    2012-12-01

    Case studies of recent tsunami impacts have proven to be extremely useful in understanding the geologic processes involved during inundation and return flow, and refining the criteria used to identify paleotsunami deposits in the geologic record. Here, we report on erosion, deposition and associated landscape change resulting from the March 11, 2011 Tohoku-oki tsunami along a nearly 4.5 km shore-normal transect on the coastal plain near Sendai, Japan. The study area on the broad, low-relief prograding coastal Sendai plain comprised a sand beach backed by ~ 3 m high sand dunes and a forest, a wetland, the Teizan canal, agricultural rice fields, buildings and roads. Field observations focused on measurements of tsunami flow characteristics (height and direction), mapping of erosion features and assessing sediment deposition based on shallow trenches at 50-100 m spacing. Recorded tsunami inundation heights reached up to about 11 m above mean sea level within the first 500 m from the shoreline and then ranged between 3 and 5 m for the next 2 km, gradually decreasing to about 3 m close to the inundation limit. The tsunami deposit generally thinned landward from an average maximum ~ 30 cm thick sand deposit in the coastal forest to a thin mud drape several mm thick near the inundation limit. A discontinuous sand-dominated sheet was prevalent to about 2800 m from the shoreline where mud content then gradually increased further landward eventually resulting in a mud-dominated deposit ranging from 3.5 cm to a few mm thickness. The overall thinning and fining of the deposit was often interrupted by localized features that led to complex sedimentological relationships over short distances. Satellite imagery taken on 14 March 2011, 3 days after the Tohoku-oki Tsunami shows prominent foreshore incisions with 100 s + meters spacing alongshore, a foredune ridge that underwent severe erosion and development of a prominent shore-parallel elongated scour depression. Our field survey

  6. Use Of Radar-Rainfall Data for the Southwest Coastal Louisiana Feasibility Study: Regional Scale Hydrologic and Salinity Modeling and Management Scenario Analysis for Chenier Plain

    NASA Astrophysics Data System (ADS)

    Meselhe, E. A.; Michot, B.; Chen, C.; Habib, E. H.

    2011-12-01

    The Chenier Plain, in Southwest Louisiana, extends from Vermilion Bay to Sabine Lake in southeast Texas. It has great economic, industrial, recreational, and ecological value. Over the years, human activities such as dredging ship channels and access canals, building roads, levees, and hydraulic structures have altered the hydrology of the Chenier Plain. These alterations have affected the fragile equilibrium of the marsh ecology. If no action is taken to restore the Chenier Plain, land loss through conversion of marsh to open water would continue. The Southwest Coastal Louisiana Feasibility Study aims at evaluating proposed protection and restoration measures and ultimately submitting a comprehensive plan to protect and preserve the Chenier Plain at the regional scale. The proposed alternatives include marsh creation, terracing, shoreline protection, and freshwater introduction and salinity control structures. A regional scale hydrodynamic and salinity transport model was developed to screen and assess the proposed restoration measures. A critical component of this modeling effort is local rainfall. The strong spatial variability and limited availability of ground-level precipitation measurements limited our ability to capture local rainfall. Thus, a radar-based rainfall product was used as a viable alternative to the rain gauges. These estimates are based on the National Weather Service from the Multi-Sensor Precipitation Estimator (MPE) algorithm. Since the model was used to perform long-term (yearly) simulations, the 4x4 km2 MPE estimates were represented as daily accumulations. The use of the radar-rainfall product data improved the model performance especially on our ability to capture the spatial and temporal variations of salinity. Overall, the model is improving our understanding of the circulation patterns and salinity regimes of the region. The circulation model used here is the MIKE FLOOD software (Danish Hydraulic Institute, DHI 2008) which dynamically

  7. Periodic isolation of the southern coastal plain of South Africa and the evolution of modern humans over late Quaternary glacial to interglacial cycles

    NASA Astrophysics Data System (ADS)

    Compton, J. S.

    2012-04-01

    Humans evolved in Africa, but where in Africa and by what mechanisms remain unclear. The evolution of modern humans over the last million years is associated with the onset of major global climate fluctuations, glacial to interglacial cycles, related to the build up and melting of large ice sheets in the Northern Hemisphere. During interglacial periods, such as today, warm and wet climates favored human expansion but during cold and dry glacial periods conditions were harsh and habitats fragmented. These large climate fluctuations periodically expanded and contracted African ecosystems and led to human migrations to more hospitable glacial refugia. Periodic isolation of relatively small numbers of humans may have allowed for their rapid evolutionary divergence from the rest of Africa. During climate transitions these divergent groups may have then dispersed and interbred with other groups (hybridization). Two areas at the opposite ends of Africa stand out as regions that were periodically isolated from the rest of Africa: North Africa (the Maghreb) and the southern coastal plain (SCP) of South Africa. The Maghreb is isolated by the Sahara Desert which periodically greens and is reconnected to the rest of Africa during the transition from glacial to interglacial periods. The SCP of South Africa is isolated from the rest of Africa by the rugged mountains of the Cape Fold Belt associated with inedible vegetation and dry climates to the north. The SCP is periodically opened when sea level falls by up to 130 m during glacial maxima to expose the present day submerged inner continental shelf. A five-fold expansion of the SCP receiving more rainfall in glacial periods may have served as a refuge to humans and large migratory herds. The expansive glacial SCP habitat abruptly contracts, by as much as one-third in 300 yr, during the rapid rise in sea level associated with glacial terminations. Rapid flooding may have increased population density and competition on the SCP to

  8. Estimating shorebird populations during spring stopover in rice fields of the Louisiana an