Accelerated drowning of the Delaware Bay coast 1800 years ago
- Univ. of Hawaii, Honolulu, HI (United States). Dept. of Geology
- Univ. of Delaware, Newark, DE (United States). Dept. of Geology
- West Chester Univ., PA (United States). Dept. of Geology and Astronomy
Paleontological, geochemical, and lithological indicators of former marine and nonmarine conditions are correlated between 13 cores from a tidal wetland (Wolfe Glade) on the southeastern coast of Delaware Bay. The cores reveal at least 5 marsh-wide transgressive episodes which the authors interpret as representing periods of marsh drowning. One of the most significant of these episodes occurred 1,800 [+-] 200 years ago (sidereal), according to 4 radiocarbon dates which bracket the facies transition. Over 40 cores have also been obtained along the tidal Leipsic River, a tributary of Delaware Bay located over 100 km from Wolfe Glade. The sediments of the Leipsic River valley contain a transgressive episode also dated at approximately 1,800 years BP (based on 4 radiocarbon analyses). In 12 cores separated by over 4 km, the authors have observed sediments deposited in a marine subtidal environment (based on lithology, and diatom analyses) abruptly overlying fluvial sand, mud, and peat. The transgressions observed at Wolfe Glade and the Leipsic River correlate with the major transgression of the sea recognized by Meyerson (1972) in wetland deposits of the New Jersey shore of Delaware Bay. These widely separated by temporally correlative transgressive facies transition suggest the occurrence of a major regional event. Because other mechanisms (rapid subsidence, autocompaction, rapid lateral erosion by tidal streams, and reduced sediment supply) are less likely, the authors propose that these transgressions were produced by an acceleration in the rate of sea-level rise 1,800 years ago in Delaware Bay.
- OSTI ID:
- 6137324
- Report Number(s):
- CONF-921058--
- Journal Information:
- Geological Society of America, Abstracts with Programs; (United States), Journal Name: Geological Society of America, Abstracts with Programs; (United States) Vol. 24:7; ISSN GAAPBC; ISSN 0016-7592
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
580000* -- Geosciences
AGE ESTIMATION
BAYS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON 14
CARBON ISOTOPES
CHEMISTRY
COASTAL REGIONS
COASTAL WATERS
DELAWARE BAY
EVEN-EVEN NUCLEI
FLUCTUATIONS
GEOCHEMISTRY
GEOLOGIC MODELS
GEOLOGY
ISOTOPE DATING
ISOTOPES
LEVELS
LIGHT NUCLEI
LITHOLOGY
NUCLEI
PALEONTOLOGY
PETROLOGY
RADIOISOTOPES
RIVERS
SEA LEVEL
SEDIMENTS
STREAMS
SURFACE WATERS
VARIATIONS
YEARS LIVING RADIOISOTOPES