All results are plotted against depth in Figures F2 and F3. The clay fraction (<2 µm) at Sites 1095 and 1096 in general varies between 30 and 60 wt%. Only a few samples taken from coarser-grained turbidites have lower clay contents. The predominantly muddy grain size of the investigated sediments is shown by Pudsey (Chap 12, Chap 25, this volume), who used a silt/clay boundary at 4 µm.
The clay mineral assemblages are dominated by smectite, illite, and chlorite. Kaolinite occurs in minor concentrations (<5%), and its distribution is therefore not shown in Figures F2 and F3. At both sites, the smectite concentration is highly variable, with values between 0% and 50%. Illite fluctuates much less; concentrations are mainly 30% to 45% at Site 1095 and 30% to 55% at Site 1096. Chlorite concentrations are 20% to 60% at both sites. Other minerals detected in the clay mineral fraction are quartz, plagioclase feldspar, K-feldspar, and amphibole.
At Site 1097, smectite varies from 3% to 27%, illite from 31% to 41%, and chlorite from 41% to 63%. The fluctuations of clay minerals are independent of the lithologies. Because of the very poor core recovery at Site 1097 and the limited number of samples, only the average clay mineral composition in combination with the regional clay mineral distribution in the surface sediments is presented (Fig. F4).