Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . aughton. In view of the fact that this is the only known marineonshore Cretaceous deposit on the whole west coast of Africa south of Angola,an as accurate as possible locality map and a description of the present conditionsof the remains of the outcrop and its relation to the overlying Tertiary sedimentsare provided. DESCRIPTION OF LOCALITY AND EXPOSURE In the sketch map (Fig. 1) compiled from an uncorrected aerial photographand Kaisers 1926 map no. 3, Granitberg, the depression running into theLangental is shown due
Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . aughton. In view of the fact that this is the only known marineonshore Cretaceous deposit on the whole west coast of Africa south of Angola,an as accurate as possible locality map and a description of the present conditionsof the remains of the outcrop and its relation to the overlying Tertiary sedimentsare provided. DESCRIPTION OF LOCALITY AND EXPOSURE In the sketch map (Fig. 1) compiled from an uncorrected aerial photographand Kaisers 1926 map no. 3, Granitberg, the depression running into theLangental is shown due east of Wanderfeld IV (Fig. 2). Subsequent to Haughtons description of the locality, extensive miningoperations were undertaken. The conglomeratic sediments overlying the bedrockwere stripped and sieved for diamonds. The area is littered with gravel mounds;the largest concentrations are indicated on the map. In places where the sedimenthas not been disturbed, the Tertiary fossils occur as typical deflation deposits. CRETACEOUS DEPOSITS NEAR BOGENFELS, SOUTH WEST AFRICA 83. LEGEND Qk Cretaceous outcrop Tertiary &Quaternary Basementdolomite Graveldumps (£) Tertiary^ hillock ©Dumped rails& sleepers Narrowgauge rail 1:*= 30000 ^—Bogenfels 1,7 km Fig. 1. Sketch map indicating locality of Tertiary and Cretaceous outcrops.(After Kaiser 1926 and uncorrected aerial photograph.) The surface is littered with rusty-brown turritelid gastropods, heterodontbivalves, ostreids, bryozoans, selachian teeth and occasional specimens of thenautiloid Aturia lotzei. An important topographical feature is a low hillock inthe western part of the depression (Fig. 3), consisting of green, sandy silts andhard, greyish-white concretionary layers with abundant Tertiary fossils. As thisis the only major topographic feature in the depression, both the author andZiegler here searched in vain for the Rhynchostreon bed and incorrectly con-cluded that the material described by Haughton was probably reworked. Th
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Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
