. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. CAMPANIAN AND MAASTRICHTIAN OSTRACODA 159 Considering the geographical position of sample 818 (in the vicinity of the Upper Cretaceous shelf break where the shelf is about 135 km wide), this suggests an outer shelf upper slope setting in shallow water (7 — 100 m). Such an unusual sedimentary environment was presumably created during a regression that may be correlated with the major regression that we have identified as commencing in Maastrichtian II in our Zululand samples (Fig. 73). SUMMARY Within
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. CAMPANIAN AND MAASTRICHTIAN OSTRACODA 159 Considering the geographical position of sample 818 (in the vicinity of the Upper Cretaceous shelf break where the shelf is about 135 km wide), this suggests an outer shelf upper slope setting in shallow water (7 — 100 m). Such an unusual sedimentary environment was presumably created during a regression that may be correlated with the major regression that we have identified as commencing in Maastrichtian II in our Zululand samples (Fig. 73). SUMMARY Within the context of the continental shelf and upper slope environments encountered in the Santonian-Campanian-Maastrichtian of south-east Africa, it is possible to summarize the palaeosedimentary environments of the ostracod faunas studied in terms of a CCBC diagram. The various fields'(assemblages 1-7. as shown in Figure 68). as well as the data from isolated samples from Needs Camp. Igoda and the Agulhas Bank are shown in Figure 75. Environ- ments deeper than 100 m ( mid-shelf and deeper, assemblage fields 4-7) lie in the central part of the diagram, with the deeper-water areas (assemblages 5b, 6 and 7) lying towards the CBC base line ( below the 30% Cytheracea line). The anti-clockwise closure of the 100 m line in the high Bairdiacea Cypridacea populations is somewhat speculative and is based on the Needs Camp popula- tions. C. Fig. 75. CCBC triangular diagram used to predict depths (in metres) of palaeosedimentary environments of ostracod assemblages in the Campanian-Maastrichtian strata of south-east Africa. Constructed from Figure 68 and Table 6. it includes data from Zululand. Igoda. Needs Camp, and Agulhas Bank. Within the dotted areas (>100 m depth), the field boundaries are those shown in Figures 68 and 69 (insert). See text for Please note that these images are extracted from scanned page images that may have been digitally enhanced for readabil
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