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Research about Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia

Source-linked reports with geographic coverage including Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia.

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

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.

Florida, Georgia, Maryland, North Carolina, South

Mapping of forested wetland: Use of Seasat radar images to complement conventional sources

Distinguishing forested wetland from dry forest using aerial photographs is handicapped because photographs often do not reveal the presence of water below tree canopies. Radar images obtained by the Seasat satellite reveal forested wetland as highly reflective patterns on the coastal plain between Maryland and Florida. Seasat radar images may complement aerial photographs for compiling maps of wetland. A test with experienced photointerpreters revealed that interpretation accuracy was significantly higher when using Seasat radar images than when using only conventional sources.

Florida, Georgia, Maryland, North Carolina, South

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

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.

Florida, Georgia, Maryland, North Carolina, South