During Leg 175, the JOIDES Resolution drilled 13 sites as part of a latitudinal transect between 5° and 32°S. All but one site (1080) yielded excellent sections with virtually complete recovery (Fig. 15). Off the Congo and Angola, drilling was restricted to the upper 200 m (or 120 m) for safety reasons. Other proposed sites off Angola (downslope of Site 1079) were taken off the list altogether during final review. Sedimentation rates typically are near 100 m/m.y.; thus, drilling at the shallow sites to the north of WR recovered sediments mainly of Quaternary age, with occasional penetration into the late Pliocene (Sites 1075 and 1077; see Fig. 16). On and south of WR, several sites had penetration to 600 meters below seafloor (mbsf). From these deeper sites, sediments dating back to the middle Mio-cene were recovered in continuous stratigraphic sections, and sediments as old as the Oligocene were recovered where sections were incomplete (Fig. 16).
Sites are located in the Lower Congo Basin (LCB; Sites 1075, 1076, and 1077), Mid-Angola Basin (MAB; Sites 1078 and 1079), Southern Angola Basin (SAB; Site 1080), Walvis Ridge (WR; Site 1081), Walvis Basin (WB; Sites 1082 and 1083), Northern Cape Basin (NCB; Site 1084), Mid-Cape Basin (MCB; Site 1085), and Southern Cape Basin (SCB; Sites 1086 and 1087; also see Fig. 1). Depth transects were achieved in four areas: LCB with three sites, MAB with two sites, WR/WB transect with three sites, and SCB with two sites. These transects will allow the assessment of offshore gradients in productivity and sediment transport, as well as depth-related effects. Drilling of APC sections (usually the uppermost 200 to 250 m) was done in triplicate (or in duplicate where time constraints required it) so that complete stratigraphic sections could be spliced together from the neighboring holes, each of which has gaps or disturbed sections between successive cores.