. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. TURONIAN, CONIACIAN, AND SANTONIAN OSTRACODA 203 7 /o 100 H 90 80 70 H 60 50 40 30 20 10 0 CONIACIAN IV Cytheracea /*^ t 1 r 1 3 5 15 SANTONIAN III J I I I L Bairdiacea & Cypridacea V. -*-4^ Cytheracea. Cytherellidae t r r 1 r 1 1 1 —r— 9 10/1 10/2 11/1 11/2 12 13 14 15 74 bed no. locality Fig. 40. Temporal trend of major groups (as percentage of total ostracod population) in Zululand outcrops. Data are three-point running means. significance is difficult to assess, other than to suggest that a s
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. TURONIAN, CONIACIAN, AND SANTONIAN OSTRACODA 203 7 /o 100 H 90 80 70 H 60 50 40 30 20 10 0 CONIACIAN IV Cytheracea /*^ t 1 r 1 3 5 15 SANTONIAN III J I I I L Bairdiacea & Cypridacea V. -*-4^ Cytheracea. Cytherellidae t r r 1 r 1 1 1 —r— 9 10/1 10/2 11/1 11/2 12 13 14 15 74 bed no. locality Fig. 40. Temporal trend of major groups (as percentage of total ostracod population) in Zululand outcrops. Data are three-point running means. significance is difficult to assess, other than to suggest that a somewhat shallower water environment may be located in this field. Palaeoecological and predicted sedimentary environments for the Santonian section of the Richards Bay BH9 borehole have been fully discussed in Dingle (1980). These data have been incorporated in various figures referred to below. Dingle et al. (1983) have discussed some of the palaeoenvironmental aspects of Upper Cretaceous sedimentation in Zululand, and have stressed the onlapping nature of the Upper Cretaceous transgression that was first recognized by Kennedy & Klinger (1971). The BH9 borehole site lies to the south of the Eteza Fault on the crest of a basement feature referred to as the Richards Bay Arch. Differential vertical movements were recognized between this area and the basin farther north under the Zululand coastal plain. The data acquired during the present study allow modifications to be made to the model presented by Dingle et al. (1983). Figure 42 shows a tentative temporal and spatial correlation of depositional environments along a transect between the False Bay-Nibela Peninsula area, the Mfolozi Valley, and BH9 (100 km in length). The diachronous nature of the post-Turonian transgression is well illustrated, with Coniacian I, Coniacian II,. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appear
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
