. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography 332 CONTINENTAL SHELF SEDIMENTATION. 39°05'N 73°58W 73°57' 73°56' TREND OF BOTTOM UNEATION TRACKLINE FIGURE 22. Current I in eat ion patterns on the central New Jersey shelf. Bars indicating lineations are over 10 times as long as features that they rep- resent. They locally represent sets of lineations. High areas are stippled. Contours in fathoms. From McKinney et al. (2974)- tide-induced "bed load partings" and flow down the gradient of
. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography 332 CONTINENTAL SHELF SEDIMENTATION. 39°05'N 73°58W 73°57' 73°56' TREND OF BOTTOM UNEATION TRACKLINE FIGURE 22. Current I in eat ion patterns on the central New Jersey shelf. Bars indicating lineations are over 10 times as long as features that they rep- resent. They locally represent sets of lineations. High areas are stippled. Contours in fathoms. From McKinney et al. (2974)- tide-induced "bed load partings" and flow down the gradient of maximum tidal current velocities until either the shelf edge or a zone of "bed load conver- gence" and sand accumulation is reached (Stride, 1963; Kenyon and Stride, 1970; Belderson et al., 1970); see Fig. 26. Each stream tends to consist of a sequence of more or less well-defined zones of characteristic bottom mor- phology and sediment texture (Fig. 27). Streams may begin in high-velocity zones [midtide surface velocities in excess of 3 knots (150 cm/sec)]. Here rocky floors are locally veneered with thin (centimeters thick) lag deposits of gravel and shell. Where slightly thicker, the gravel may display "longitudinal furrows" parallel to the tidal current (Stride et al., 1972), a bed form related to sand ribbons (see Chapter 10, p. 170). Between approximately and knots (125-150 cm/sec) sand ribbons are the dominant bed form (Kenyon, 1970). These features are up to 15 km long and 200 m wide, and usually less than a meter deep. Their materials are in transit over a lag deposit of shell and gravel. Kenyon has distinguished four basic pat- terns that seem to correlate with maximum tidal current velocity and with the availability of sand (Chapter 10, Fig. 15). Further down the velocity gradient, where midtide surface velocities range from 1 to 2 knots (50-100 cm/sec), sand waves are the dominant bed form. Where the gradient of decreasing tidal velo
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