. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography SANDS ON THE VIRGINIA SHELF 881 may contain as much as 15 percent clay, and their Eh is probably further reduced by an abundance of clay-sized organic matter. To the extent that these deductions are correct, coarse bottom sands should have the most oxidized coatings and should be the most nearly yellow- brown, while fine sands should be the least oxidized, and should be pigmented in some shade of green or blue (partially reduced iron) or neutral (to
. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography SANDS ON THE VIRGINIA SHELF 881 may contain as much as 15 percent clay, and their Eh is probably further reduced by an abundance of clay-sized organic matter. To the extent that these deductions are correct, coarse bottom sands should have the most oxidized coatings and should be the most nearly yellow- brown, while fine sands should be the least oxidized, and should be pigmented in some shade of green or blue (partially reduced iron) or neutral (totally reduced iron). The fine sands might be further pigmented a dark hue by their characteristically higher percent of heavy minerals and organic-rich clay fraction. CORRELATION OF GRAIN SIZE AND COLOR, VIRGINIA SHELF SANDS Methods In order to test this hypothesis, we measured the grain size and color of 149 samples of sand collected from False Cape submarine sand ridge system on the Virginia shelf off False Cape, Virginia. The samples had been collected during a study of the ridge system in order to relate grain size to topography (Swift and others, 1972a). The samples were collected with a Shipek grab sampler on a 1 km grid (Fig. 1). This sample collection was selected for study because grain size varied through 4 phi units in an area so small that regional petrographic gradients influencing color might be excluded. Median diameter of the — 1 to 4 phi fraction was determined by means of a modified Woods Hole rapid sediment analyzer (Sanford and Swift, 1972). The samples had been stored for a year before color coding, which according to Stanley (1969) should shift hue to slightly more yellow values. Color was determined by means of visual comparison of wet samples with "the Munsell Book of Color" (Munsell Color Co., 1929-1960), in terms of hue, value, and chroma. All estimations were made under an overhead fluorescent light. Fifteen of the samples were selected at
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