Depositional Environments and Stratigraphy of Quaternary Paleochannel Systems Offshore of the Georgia Bight, Southeastern USA

AbstractThe mesotidal coast of Georgia encompasses diverse sedimentary features and depositional environments, most of which typify major facies of the entire Georgia Bight – a broad embayment on the southeastern U.S. shelf. Barrier island strandline environments especially include tidal inlets and shoals, the beach shoreface, foreshore, and backshore, and dunes and washover fans. Low energy beach segments may grade directly into small seaside tidal flats. Relict salt marsh deposits crop out on erosional beaches. All deposits are in dynamic equilibrium with fluctuating coastal conditions and a gradual rise in sea level.Most of these facies are important in interpreting ancient epeiric transgressive/regressive coastal sequences. Pronounced local variations in the overall sequence result from complex latero-vertical relationships between (1) the shoreface, foreshore, and shoals, and (2) the shoals, low energy beaches, and beach-related tidal flats. Washover fans and relict deposits on erosional beaches cause perturbations within present day lateral relationships but are normal in transgressive facies tracts along such coasts. Close stratigraphic control of outcrops or cores would be necessary for detailed reconstructions of, or correlations among, ancient analogs.

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Benthic foraminiferal zonation in deep-water carbonate platform margin environments, northern Little Bahama Bank

Journal of Paleontology ◽

10.1017/s0022336000058819 ◽

1988 ◽

Vol 62 (01) ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Ronald E. Martin

Keyword(s):

Deep Water ◽

Benthic Foraminifera ◽

Carbonate Platform ◽

Sedimentary Facies ◽

Depositional Environments ◽

Near Surface ◽

Sediment Gravity Flows ◽

Gravity Flows ◽

Platform Margin ◽

Water Carbonate

The utility of benthic foraminifera in bathymetric interpretation of clastic depositional environments is well established. In contrast, bathymetric distribution of benthic foraminifera in deep-water carbonate environments has been largely neglected. Approximately 260 species and morphotypes of benthic foraminifera were identified from 12 piston core tops and grab samples collected along two traverses 25 km apart across the northern windward margin of Little Bahama Bank at depths of 275-1,135 m. Certain species and operational taxonomic groups of benthic foraminifera correspond to major near-surface sedimentary facies of the windward margin of Little Bahama Bank and serve as reliable depth indicators. Globocassidulina subglobosa, Cibicides rugosus, and Cibicides wuellerstorfi are all reliable depth indicators, being most abundant at depths >1,000 m, and are found in lower slope periplatform aprons, which are primarily comprised of sediment gravity flows. Reef-dwelling peneroplids and soritids (suborder Miliolina) and rotaliines (suborder Rotaliina) are most abundant at depths <300 m, reflecting downslope bottom transport in proximity to bank-margin reefs. Small miliolines, rosalinids, and discorbids are abundant in periplatform ooze at depths <300 m and are winnowed from the carbonate platform. Increased variation in assemblage diversity below 900 m reflects mixing of shallow- and deep-water species by sediment gravity flows.

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Modern Clastic Depositional Environments, South Carolina: Charleston to Columbia, South Carolina, July 20–25, 1989

10.1029/ft371 ◽

1989 ◽

Author(s):

Miles O. Hayes ◽

Walter J. Sexton

Keyword(s):

South Carolina ◽

Depositional Environments

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Review for "Biostratigraphy and depositional environments of the Palaeocene–Eocene succession at Um El Huwaitat area, Eastern Desert, Egypt"

10.1002/gj.4024/v1/review1 ◽

2020 ◽

Keyword(s):

Eastern Desert ◽

Depositional Environments

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Decision letter for "Biostratigraphy and depositional environments of the Palaeocene–Eocene succession at Um El Huwaitat area, Eastern Desert, Egypt"

10.1002/gj.4024/v1/decision1 ◽

2020 ◽

Keyword(s):

Eastern Desert ◽

Depositional Environments

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Decision letter for "Biostratigraphy and depositional environments of the Palaeocene–Eocene succession at Um El Huwaitat area, Eastern Desert, Egypt"

10.1002/gj.4024/v3/decision1 ◽

2020 ◽

Keyword(s):

Eastern Desert ◽

Depositional Environments

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Urbanization impacts on production and recruitment of Fundulus heteroclitus in salt marsh creeks

Marine Ecology Progress Series ◽

10.3354/meps13378 ◽

2020 ◽

Vol 645 ◽

pp. 187-204

Author(s):

PJ Rudershausen ◽

JA Buckel

Keyword(s):

Salt Marsh ◽

Salt Marshes ◽

Fundulus Heteroclitus ◽

Multiple Factor Analysis ◽

Southeastern Usa ◽

Density Dependent ◽

Dependent Relationship ◽

Juvenile Abundance ◽

The Relationship ◽

Throw Trap

It is unclear how urbanization affects secondary biological production in estuaries in the southeastern USA. We estimated production of larval/juvenile Fundulus heteroclitus in salt marsh areas of North Carolina tidal creeks and tested for factors influencing production. F. heteroclitus were collected with a throw trap in salt marshes of 5 creeks subjected to a range of urbanization intensities. Multiple factor analysis (MFA) was used to reduce dimensionality of habitat and urbanization effects in the creeks and their watersheds. Production was then related to the first 2 dimensions of the MFA, month, and year. Lastly, we determined the relationship between creek-wide larval/juvenile production and abundance from spring and abundance of adults from autumn of the same year. Production in marsh (g m-2 d-1) varied between years and was negatively related to the MFA dimension that indexed salt marsh; higher rates of production were related to creeks with higher percentages of marsh. An asymptotic relationship was found between abundance of adults and creek-wide production of larvae/juveniles and an even stronger density-dependent relationship was found between abundance of adults and creek-wide larval/juvenile abundance. Results demonstrate (1) the ability of F. heteroclitus to maintain production within salt marsh in creeks with a lesser percentage of marsh as long as this habitat is not removed altogether and (2) a density-dependent link between age-0 production/abundance and subsequent adult recruitment. Given the relationship between production and marsh area, natural resource agencies should consider impacts of development on production when permitting construction in the southeastern USA.

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