Figure F7. A. Uninterpreted MCS dip profile EW00-01-66 from the southern part of the survey grid showing locations of primary and alternate drill sites (see Fig. F3 for location). B. Interpretation showing sequence boundaries and selected locations of onlap, truncation, and downlap (arrows). Circles = clinoform breakpoints, representing paleoshelf edges. Paleoshelf edges from Unconformities U4–U8 prograde steadily. The amount of progradation decreases from Unconformities U8 to U12, increasing again from Unconformities U13 to U19. Unconformities U4–U8 are onlapped and truncate underlying reflections; internal reflection geometries from Unconformities U4–U9 are mainly sigmoid. Sites CB-01A and CB-02A sample these sequence boundaries landward of their breakpoints. Site CB-02A also samples the paleoslope of Unconformity U6, and Site CB-03B samples paleoslopes of Unconformities U4–U7. In contrast, Unconformities U10–U19 are downlapped on paleoshelves, but also truncate underlying reflections, and internal reflection geometries from Unconformity U9–seafloor are oblique. Site CB-03B samples these sequence boundaries landward of their breakpoints. Sediment drift development in this area had largely ceased by Unconformity U4. Only Drift D5 is present; it is capped by a postdrift slope platform at Unconformity U4. Prograding clinoforms dominate later sequences and the slope steepens (to 3°–5°). Drifts migrate northwestward (landward) on dip profiles. Erosional unconformities at the landward edges of drift moats are diachronous and intersected by multiple sequence boundaries. MP = Marshall Paraconformity.
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