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Micropaleontological, geophysical, and chronologic data indicate that normal salinity conditions occurred over currently estuarine back-barrier areas of the Outer Banks of eastern North Carolina during the peak of the Medieval Climate Anomaly. Sedimentary units several meters thick, containing foraminiferal assemblages usually found on the continental shelf of North Carolina, are present in 16 vibracores acquired from the shallow shoals of Pamlico Sound behind Cape Hatteras. Optically stimulated luminescence age estimates from these normal salinity units range from approximately 1360 to 980 calibrated years (cal yr) BP, corresponding with a previously documented collapse of a segment of the southern Outer Banks. It is vital to understand past scenarios of barrier island formation and segmentation to provide insight on how these islands may react to future change in climate and sea level. [ABSTRACT FROM AUTHOR]

Studies the burrows and trails produced by Quinqueloculina impressa Reuss, a benthic foraminifer, in fine-grained sediment. Assessment of the capability of the benthic foraminifer Quinqueloculina impressa Reuss for producing sediment disturbances and ichnofossils; Distinct burrows in silts and silty-clays; Types of burrows.

Foraminiferal, sedimentological, geophysical, and geochronologic data were utilized to elucidate the late Quaternary geologic development of the Croatan Beach Ridge Complex (CBRC), Bogue Sound, and Bogue Banks, North Carolina, USA. The CBRC is a relict beach ridge feature located on the mainland. It is separated from the modern barrier island, Bogue Banks, by Bogue Sound. Seventeen cores along shore-normal and shore-parallel transects provided material for sedimentologic and foraminiferal analysis and resulted in the recognition of seven depositional facies representing a variety of coastal depositional environments. Chronologic and depositional facies data suggest the CBRC was initiated during MIS 5a and rapid southward progradation produced a cape structure. Eolian reactivation of the upper sand of the CBRC occurred during the last glacial maximum (∼18 ka). The age of flood tide delta deposits in Bogue Sound suggests that the Holocene barrier island, Bogue Banks, had formed by ∼6 ka. Shoreface ravinement resulted in a shoreface landward of the present shoreline by ∼3.5 ka. Seaward and westward spit progradation of Bogue Banks began ∼1.7 ka and continued to ∼1.3 ka. Normal marine salinity conditions were present in Bogue Sound ∼1.1 ka, suggesting removal of at least the narrowest parts of the barrier island, coeval with a previously documented segmentation of the southern Outer Banks barrier islands. Previous work has linked this segmentation to climate warming and increased tropical storm activity during the Medieval Climate Anomaly. This study illustrates the complex response of this coastal system to Pleistocene and Holocene sea-level and climate change over two major sea-level cycles. In particular, the regional geomorphology during MIS5a and the Holocene sea-level highstand differ significantly and this, in large part, was controlled by the antecedent geologic framework, resulted in the contrasting more localized coastal geomorphic response. [ABSTRACT FROM AUTHOR]