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Research about North Carolina, South Carolina

Source-linked reports with geographic coverage including North Carolina, South Carolina.

At least 37 records · Page 2Linked to original sources

Ecological data collected in the Santee River basin and coastal drainages, North and South Carolina, 1996–98

As part of the National Water-Quality Assessment Program, ecological investigations were conducted in 23 reaches of 16 streams in the Santee River Basin and Coastal Drainages study unit in North and South Carolina during 1996-98. Habitat characteristics, such as stream width and depth, bank composition, bank vegetative cover, stream shading by overhanging vegetation, and streambed composition were recorded. Algal and benthic invertebrate communities were sampled using quantitative and qualitative techniques. These data will provide information needed to: (1) support findings of the effects of human landuse activities on water quality by augmenting or enhancing physical and chemical water-quality data, (2) provide a basic overview of aquatic community structure in selected stream reaches in the study unit, and (3) provide a means for comparing aquatic communities in subsequent years of the assessment program.

North Carolina, South Carolina

Water quality in the Santee River basin and coastal drainages, North and South Carolina, 1995-98

Surface water sampled in the Santee River basin and coastal drainages generally meets existing Federal and State guidelines for drinking-water quality and protection of aquatic life. However, urban and agricultural land uses have affected water quality, as indicated by elevated concentrations of bacteria, pesticides, and nutrients in basins dominated by these land uses.

North Carolina, South Carolina

Shallow ground-water quality in the Coastal Plain of Columbia, South Carolina, 1996

As part of the National Water-Quality Assessment (NAWQA) Program, the U.S. Geological Survey (USGS) oversaw the installation of 30 shallow monitoring wells in the Columbia, South Carolina metropolitan area. The ground water sampled from these wells was used to study the recent effects of human activities on shallow ground water in an urban setting. Well locations were selected in residential and commercial areas constructed between 1960 and 1990 while all industrial and agricultural areas were avoided. Samples were collected and analyzed for major ions, nutrients, pesticides, and volatile organic compounds (VOCs) dunng 1996. This report describes the results of this investigation of shallow ground-water quality.

North Carolina, South Carolina

Tracing sediment dispersal on nourished beaches: Two case studies

The event- to decade-scale patterns of sediment dispersal on two artificially nourished beaches have been mapped using a combination of geophysical surveys, closely-spaced vibracores, and repeated beach profiles. At both Wrightsville Beach, NC and Folly Island, SC the sediment used for beach nourishment is macroscopically distinct from native sediment and can be used to identify sediment transport pathways and infer mechanisms for across-shelf transport. The data from both sites demonstrate that significant quantities of nourishment sediment are being transported seaward onto the inner continental shelf. The time and space scales of this transport are of engineering interest for the planning, design and long-term maintenance of nourished beaches.

North Carolina, South Carolina

Pesticides in surface waters of the Santee River basin and coastal drainages, North and South Carolina

Introduction This report summarizes the available pesticide data for surface waters in the Santee River Basin and coastal drainages (SANT) study area, as part of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program. Data from the U.S. Environmental Protection Agency Storage and Retrieval database and data collected by the USGS in the SANT NAWQA study area were assessed. A description of the study area is followed by an estimate of pesticide application data. Detected pesticides and their reported maximum concentrations are summarized. Pesticide concentrations are compared with applicable water-quality standards. Seasonality of pesticide concentrations in surface water in the SANT NAWQA study area also is assessed.

North Carolina, South Carolina

Offset-vertical seismic profiling for marine gas hydrate exploration: Is it a suitable technique? First results from ODP Leg 164

Walkaway vertical seismic profiles were acquired during Ocean Drilling Project (ODP) Leg 164 at the Blake Ridge to investigate seismic properties of hydrate-bearing sediments and the zone of free gas beneath them. An evaluation of compressional (P-) wave arrivals Site 994 indicates P-wave anisotrophy in the sediment column. We identified several shear (S-) wave arrivals in the horizontal components of the geophone array in the borehole and in data recorded with an ocean bottom seismometer deployed at the seafloor. S-waves were converted from P-waves at several depth levels in the sediment column. One of the most prominent conversion points appears to be the bottom simulating reflector (BSR). It is likely that other conversion points are located in the zone of low P-wave reflectivity above the BSR. Modeling suggests that a change of the shear modulus is sufficient to cause significant shear conversion without a significant normal-incidence P-wave reflection.

North Carolina, South Carolina

Sediment transport and deposition in Lakes Marion and Moultrie, South Carolina, 1942-85

Lakes Marion and Moultrie, two large reservoirs in the South Carolina Coastal Plain, receive large inflows of sediment from the Santee River. The average rate of sediment deposition for both lakes during the period 1942-85 was about 0.06 inch per year, or about 800 acre-feet per year. The rate during 1983-85 was about 0.037 inch per year, or about 490 acre-feet per year, reflecting the decreasing trend in sediment inflow. This is a reversal of a trend toward increasing suspended- sediment concentrations in streams that were caused by farming practices in the southern Piedmont from about 1800 to about 1920. Only a small part of the eroded sediment has been carried out of the Piedmont, but the remaining sediment is becoming less available for transport. Sediment deposition is concentrated in several areas of upper Lake Marion where the velocity of the incoming water decreases significantly. Beds of aquatic macrophytes appear to encourage deposition which, in turn, creates favorable habitat for the plants. The rate of sediment accumulation in Lakes Marion and Moultrie averaged 650,000 tons per year during 1983-85, reflecting a trap efficiency of 79 percent of the total sediment inflow of 825,000 tons per year. Thickness of post-impoundment sediment varies from about 11 feet near the mouth of the Santee River in Lake Marion to 0 feet in Lake Moultrie near Bonneau. Sediments in Lake Marion tend to have finer texture and higher contents of organic matter, nutrients, and trace metals than those in Lake Moultrie.

North Carolina, South Carolina

National Water Quality Assessment Program; the Santee Basin and coastal drainage, North Carolina and South Carolina

In 1991, the U.S. Geological Survey (USGS), U.S. Department of the Interior, began a National Water-Quality Assessment Program (NAWQA). The long-term goals of NAWQA are to describe the status of and trends in the quality of a large representative part of the Nation's surface- and ground-water resources and to identify all the major factors that affect the quality of these resources. In addressing these goals, NAWQA produces water-quality information that is useful to policymakers and managers at State, Federal, and local levels. NAWQA emphasis is on regional scale water-quality problems. The program does not diminish the need for smaller scale studies and monitoring designed and conducted by State, Federal, and local agencies. NAWQA, however, provides a large-scale framework for conducting many of these activities and an understanding about regional and national water-quality conditions that cannot be acquired from these other programs and studies. Studies of 60 hydrologic systems that include parts of most major river basins and aquifer systems are the building blocks of the national assessment. The areas of the 60 study units range in size from 1,000 to more than 60,000 square miles (mi 2 ) and represent 60 to 70 percent of the Nation's water use and population served by public water supplies. Twenty investigations were begun in 1991, 20 investigations began in 1994, and 20 are planned to begin in 1997. The assessment activities in the Santee River Basin and Coastal Drainage began in 1994.

North Carolina, South Carolina

Gulf trough: The Atlantic connection

Analyses of seismic reflection profiles and stratigraphic data indicate a continuation of the Gulf trough trend across eastern South Carolina and offshore between Cape Fear and Cape Hatteras, North Carolina. Seismic profiles show a linear northeast-trending zone of nondeposition and erosion and areas of chaotic deposition in the Eocene and Oligocene sections. The character of deposition and erosion along this trend is similar to that produced by bottom currents under the core of the present Gulf Stream. The trend separates deep-water from shallower water deposits, indicating that the erosion was produced by strong marine currents flowing through the Gulf trough in the high sea levels of middle Eocene through early Oligocene time.

North Carolina, South Carolina