. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography LATE QUATERNARY STRATIGRAPHY, INNER VIRGINIA SHELF 1795 deposit. Gravel and sand-sized shell fragments from the uppermost m of core 4 were determined by radiocarbon methods to be older than 37,000 yrs Faunal Analysis. Forty-four species of mollusks were recovered from the medium greenish-gray, muddy, fine sand of unit B. Shallow marine species such as Macoma balthica, Mulinia lateralis, Abra equalis, and Ensis directus are abundant and domi
. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography LATE QUATERNARY STRATIGRAPHY, INNER VIRGINIA SHELF 1795 deposit. Gravel and sand-sized shell fragments from the uppermost m of core 4 were determined by radiocarbon methods to be older than 37,000 yrs Faunal Analysis. Forty-four species of mollusks were recovered from the medium greenish-gray, muddy, fine sand of unit B. Shallow marine species such as Macoma balthica, Mulinia lateralis, Abra equalis, and Ensis directus are abundant and dominate the fossil assemblage. These forms are found today from the low tide line to a depth of 12 m. Most shells are disarticulated but do not show evi- dence of excessive abrasion, except locally in sandy zones. A faunal discontinuity between the coarse basal horizon and the overlying strata is especially striking in core 3 (Fig. 7). Correlation. On the basis of its stratigraphic position and radiocarbon data, the unit is tentatively correlated as the offshore equivalent of the Pleistocene Great Bridge Formation- Sandbridge Formation sequence of the ad- jacent coastal plain, as mapped by Oaks (1964). The lower portion of unit B may be the partial equivalent of the Great Bridge Formation, which was noted by Oaks as being a relatively widespread subsurface formation throughout the adjacent coastal region of southeastern Virginia. Oaks describes the Great Bridge Formation as consisting of "coarse sand and peat of freshwater origin restricted to channels cut in the top of Miocene sediments and grad- ing upward into widespread, unoxidized, soft, silty clay and silty fine ; He interprets this stratigraphic pattern as a fluvial lithosome, grading upward into an estuarine-lagoonal lithosome. The closest onshore control, where the stratigraphic relations of the Great Bridge Formation are moderately defined, is Oaks' (1964) section HH' (Fig. 4), which terminates at the coas
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