Physical Sciences and Mathematics Commons^™

The Effects Of Two Polycyclic Aromatic Hydrocarbons Benzo[A]Pyrene And Naphthalene On Reproductive Success Embryological Development Larval Physiology And Mortality Of The Mud Crab Rhithropanopeus Harisii (Gould), Gregory V. White

OES Theses and Dissertations

Polycyclic aromatic hydrocarbons (PAHs) such as naphthalene (Nap) and benzo[a]pyrene (B[a]P) are common in the water column and sediments of estuarine and coastal areas. The mud crab Rhithropanopeus harrisii was exposed to varying concentrations of Nap or B[a]P to determine the effects on reproductive success, embryological development, larval physiology and mortality. Nap and B[a]P decreased hatching success and prolonged embryological development. Both pollutants produced high abnormality frequencies for egg exposed larvae. Molt frequency and respiratory rates of larvae from non-exposed eggs were more chronically affected by these pollutants than were egg exposed larvae. The EC₅₀ concentrations were determined for …

Trace Metals And Pyrite In Sediments Of Chesapeake Bay, Robert S. Kluckhohn

OES Theses and Dissertations

The formation and cycling of iron sulfides within anoxic sediments can affect the cycling of trace metals. The sediments at station CB-27 (near Annapolis, Maryland) in Chesapeake Bay were rich in FeS (39% of TS), low in greigite (3.6% of TS), and has a relatively constant pyrite concentration (50 - 60% of TS) with depth. The percent composition of total metals in pyrite were 25.7% cu, 11.8% Zn, 15.8% Fe, and non-detectable to 2.1% Cd. At Station CB- 28 (near the Choptank River), the sediments were low in FeS (1.7% of TS), richer in greigite (up to 14% of TS), …

Hydrogeology And Water Budget Analysis Of Two Interdunal Ponds Nags Head Woods Ecological Preserve, Dare County, North Carolina, Richard A. Hisert

OES Theses and Dissertations

Ground-water-fed interdunal ponds in Nags Head Woods Ecological Preserve lose as much as 7600 m³ yr^-1 of water through evaporation. This withdrawal of groundwater is sufficient to significantly alter flow patterns through the surficial aquifer on Bodie Island, N.C. Statistical analyses of evaporation estimates derived by various methods indicate a weak correlation, (r²=0.4-0.5) between pan evaporation data from Aurora, N.C. and pond evaporation at Nags Head Woods calculated by water budget analyses.

Results of stratigraphic and pedologic analyses in and around the ponds indicate that the ponds formed after development of multiple generations of dunes. This …

The Hydrogeology And Leachate Generation Of An Alum Sludge Lagoon Chesapeake Virginia, Charles M. Darling

OES Theses and Dissertations

In 1986 the City of Chesapeake, Virginia began to dig shallow ponds ("lagoons") to contain alum sludge, a waste generated by the City from the process of treating potable water. Borings at the disposal site reveal that the near-surface geologic units include a thin mud-rich facies which overlies a thick sandy facies, both of which are in the Lynnhaven Member of the Tabb Formation. At 7 meters depth, a clay-rich facies of the Yorktown Formation (Morgarts Beach Member?) underlies the sandy water table aquifer. Water levels from twenty observation wells and two monitoring wells installed into the water table aquifer …

The Role Of Longshore Sediment Transport In The Loss Of Fill Material From An Estuarine Groin System, R. Neville Reynolds

OES Theses and Dissertations

The influence of shoreline structures on longshore sediment transport and the evolution of a stable beach planform was investigated at Willoughby Spit, Virginia following the placement of 410,590 cubic meters of beach fill within a groin system. Shoreline changes and wave conditions in a single groin compartment, and the growth rate of a downdrift terminal spit were monitored during 1985 and 1986. Short term fluctuations in the shoreline position within the groin compartment suggested an episodic westerly movement of sediment through the groin system. Primary sediment moving events were associated with northerly winds which produced waves up to 50 cm …

Metal Mobilization From A Near-Shore Lake Sediment Under Simulated Acidic Groundwater Inputs, Raveendra V. Ika

OES Theses and Dissertations

Simulation of acidic groundwater passing through lake sediments was conducted under controlled conditions in a laboratory. Three sediment cores collected intact from the near-shore region of an acidic lake were subjected to simulated groundwater inputs of initially identical chemistry for a seven day period. Following this period water being used in the simulation for two of the sediment cores was acidified by hydrochloric acid (HC1) addition to examine the ability of these sediments to neutralize acidic groundwater with varying H⁺ concentration.

Simulated acidic water passing through the sediment cores mobilized significant amounts of metals. The sediment acted as a …

A Comparison Of Metals In Several Ahermatypic Corals And Surficial Sediments: Mobile Pinnacles And Hoffa Reef, Northcentral Gulf Of Mexico, Kathryn M. Conko

OES Theses and Dissertations

Metal concentrations in marine sediment and carbonate secreting invertebrates are representative of surrounding environmental chemistry. Aluminum, Ba Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, and Zn were measured in carbonate and terrigenous phases of the $<$63 um fraction of sediment samples from two locations in the northcentral Gulf of Mexico. Enrichment factors indicate that Al, Ba, Cu, Cr, Mg, Mn, and Ni are all slightly depleted in these sediments relative to crustal abundances. Discriminant function analyses shows that the concentrations of five elements differ between locations.

Ahermatypic coral (106 specimens) from five genera collected from the study sites were analyzed for Cd, Cu, Cr, Pb, Zn, Mn, Sr, Ba, Fe, Ca and Mg. Eight elements vary between some genera, Al and Ba also vary in concentration in corals between either location. All elements except Sr are significantly depleted in the coral with respect to Ca in the …

The Effects Of Variable Parameters On The Behavior Of Initial Wind Waves, Glen Harvey Wheless

OES Theses and Dissertations

The generation mechanism of short wind waves is generally thought to be a viscous instability at the air-sea interface. The short, regular waves arising from a sudden wind on a still water surface have a dispersion relation which is characteristic of gravity-capillary waves. The effects of variable surface tension, viscosity and shear flow parameters on the behavior of these waves were studied.

A numerical hydrodynamic stability analysis of a coupled laminar shear flow was accomplished by integrating a transformed version of the Orr-Sommerfeld equation, subject to the boundary conditions at a two-fluid interface. Unbounded growth problems usually encountered in a …

Middle Eocene Foraminifera From The Piney Point Formation Of The Virginia And Maryland Coastal Plain, Megan S. Jones

OES Theses and Dissertations

This study examines the foraminiferal fauna, both benthic and planktonic, of the outcropping (45 samples) and subsurface (31 samples) middle Eocene Piney Point Formation in Virginia and Maryland. The primary objective of this study is to further refine the depositional history of the Salisbury Embayment which is represented by the middle Eocene Piney Point Formation. Ninety-six species of benthic and planktonic foraminifera were identified in this study. Of these, several are characteristic of the middle Eocene: Asterigerina texana, Hanzawaia danvillensis, Ceratobulimina exima, Cibicides westi, Chiloguembelitria columbiana, C. stavensis, Testacarinata inconspicua and Pseudohastigerina wilcoxensislmicra. While these were relatively abundant, diagnostic middle …