. The Eastern Bering Sea Shelf : oceanography and resources / edited by Donald W. Hood and John A. Calder. Oceanography Bering Physical and biological sedimentary structures 1275 Figure 70-6a. Transgressive lag gravel over glacial till shown in box-core slab face. Note Hemithiris psittacea (brachiopod) and bryozoan skeletons on surface. Water depth 41 m. Figure 70-6b. Epoxy cast of box core containing thick, well-sorted transgressive lag gravel from —30 m shoreline stillstand (Nelson and Hopkins 1972). Note faint cross- bedding in center of cast. Water depth 30 m. Figure 70-6c. Box core-
. The Eastern Bering Sea Shelf : oceanography and resources / edited by Donald W. Hood and John A. Calder. Oceanography Bering Physical and biological sedimentary structures 1275 Figure 70-6a. Transgressive lag gravel over glacial till shown in box-core slab face. Note Hemithiris psittacea (brachiopod) and bryozoan skeletons on surface. Water depth 41 m. Figure 70-6b. Epoxy cast of box core containing thick, well-sorted transgressive lag gravel from —30 m shoreline stillstand (Nelson and Hopkins 1972). Note faint cross- bedding in center of cast. Water depth 30 m. Figure 70-6c. Box core-slab face exhibiting shell lag at base of transgressive fine-grained sand. The shell layer was composed of equal amounts of Hyatella arctica and Macoma calcarea and probably formed as a storm lag during lower sea level. The layer was found in an isolated small basin at a water depth of 43 m. Figure 70-6d. Bioturbated coarse sand and shell layer composed entirely of Echinarachnius parma (sand dollars) in current-winnowed fine sand over a shoal crest. Water depth 35 m. Figure 70-6e. Box-core slab face showing thick light- colored storm-sand layers in Yukon silt 30 km from the modern Yukon subdelta. Note that the thick upper sand most recently formed is not bioturbated, whereas only cross-laminated sand lenses remain in the lower bioturbated bed. Water depth 11m. Figure 70-6f. Radiograph of well-defined thin storm- sand layers in late Holocene Yukon silt 75 km offshore from the present subdelta. Thoroughly bioturbated older Yukon silt underlies well-structured beds in younger Yukon silt (after Nelson and Creager 1977). Note rippled and wavy bedded sand beds (light-colored) with small- scale cross and flat lamination. Water depth 16 m. Figure 70-6g. Radiograph showing shell and pebble lags in the upper and lower parts of the core and numerous thin sand layers in between. Both probably developed by storm reworking of Yukon silt 110 km from the present Yukon subdelta. Note that upp
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