Cape Peninsula Geology 2003


View north from Sea Point along the wavecut platform of Malmesbury Group metasediments	View south from Sea Point along the Cape Granite outcrops	Students inspect the complex migmatite zone of the Sea Point contact between the Malmesbury Group and Cape Granite	Migmatite zone within the Sea Point contact

Detail of the migmatite zone, Sea Point contact	Transition between the migmatiite zone and the main granite, Sea Point contact	Fierce Atlantic swells crash over granites at the Sea Point contact	View east from the Sea Point contact towards Lions Head, showing an outlier of Cape Supergroup resting on granite

View across Llandudno Bay, cut into Cape Granite	Atlantic swells march into Llandudno Bay	View south towards Chapmans Peak	Unusual outcrop of Graafwater Formation strata way below the main contact, East Fort, Hout Bay

Students prepare for the seaward inspection of Chapmans Peak from Hout Bay Harbour	Chapmans Peak from Hout Bay Harbour	North end of Chapmans Peak, showing the basement granite overlain by sedimentary strata of the Cape Supergroup	South end of Chapmans Peak Drive, coinciding exactly on the unconformity between the Cape Granite below and the Graafwater and Peninsula Formations above

Middle section of Chapmans Peak Drive, with reconstruction of the new road via a half tunnel cut into the Graafwater Formation	Negotiating the massive Atlantic swells in Hout Bay	Students taking on sea water in Hout Bay	Hout Bay seafarers

Constantiaberg, showing folded sandstone strata of the Peninsula Formation within a thrust zone	Granite outcrops on the False Bay coast at Froggy Pond	Euhedral crystals of bluish green cordierite within the Cape Granite	Cretaceous dolerite dyke cutting the Cape Granite, Froggy Pond

Chilled contact between the dark dolerite and coarse-grained Cape Granite, Froggy Pond	View from Froggy Pond across False Bay towards a floating drill rig used for oil exploration	View from above Muizenberg across the False Bay coast towards Swartklip	High cliffs cut into Pleistocene dunes, Wolfgat Nature Reserve

Atop the Wolfgat cliffs, cut into partly consolidated fossil dunes of the Pleistocene Langebaan Formation	Traversing the crumbling cliffs at Wolfgat Nature Reserve, False Bay	Pipe nodules of calcrete developed around roots, Wolfgat Nature Reserve, False Bay	Wind erosion of calcretised fossil dunes, Wolfgat Nature Reserve, False Bay

Cliffline exposures of estuarine sands, Swartklip	Darkened paleosol (ancient buried soil horizon), Swartklip	Shell rich layers in the partly consolidated sands at Swartklip	Complete bivalve fossil in the shelly sands at Swartklip


Wavecut platform at Bloubergstrand, displaying thinly bedded greywacke and shale of the Malmesbury Group	Tightly folded greywacke sandstone and shale strata of the Malmesbury Group, Blouberg Strand	Tight closure in a steeply plunging fold, Bloubergstrand	Thin quartz veins cross cutting vertical greywacke beds, Malmesbury Group, Bloubergstrand

White quartz filled veins in massive greywacke sandstone, Malmesbury Group, Bloubergstrand	Red outcrops of volcanoclastic sediments associated with basaltic pillow lavas, Bloubergstrand	Large rounded volcanic clasts in the Bloubergstrand Member, Malmesbury Group	Red outcrops of volcanoclastic sediments associated with basaltic pillow lavas, Bloubergstrand

View NW along strike across Big Bay, Bloubergstrand, of basaltic metavolcanics	Fractured pillow lavas, Bloubergstrand	In reality the weather was impossible at Blouberg on the day, so this is what we saw	Diorite outcrops on the shore at Yzerfontein

Dark gabbro xenolith enclosed in diorite, Yzerfontein	Xenolith of gabbro within mottled pyroxene diorite, Yzerfontein	Contacts between two phases of diorite, Yzerfontein	Narrow white aplite veins cross cutting diorite, Yzerfontein

Net veining of pink aplitic granite in diorite, Yzerfontein	Fractures exploited by hydrothermal fluids causing the red alteration within the diorite, Yzerfontein	Green epidote alteration in diorite, Yzerfontein	South end of Langebaan Lagoon at Geelbek, showing the transition to supratidal marshes

Atlantic coastline next to Langebaan Lagoon, showing the prograding foredunes	Tranquil waters of Langebaan Lagoon	Assembled class overlooking high tide, Langebaan Lagoon	Beach barrier between the intertidal zone (left) and the supratidal marshes (right), Langebaan Lagoon

Sinuous tidal channels feeding the supratidal marshes, Langebaan Lagoon	Persistent rain and the tidal flow harry the group	High angle dune bedding exposed in the Preekstoel, a stack detached from the cliffs that border Langebaan Lagoon at Kraal Bay	Transition between horizontal estuarine sands of the Velddrif Formation (bottom) and the overlying dunes, Krral Bay

View east from Kraal Bay towards the granite Seeberg, Langebaan Lagoon	Dehydration reactions at Windstone Backpackers Lodge, Langebaanweg	Coarse grained granite at Hoedjiespunt, with the artificial causeway to Marcus Island, Saldanha Bay	Entrance to Saldanha Bay

Traversing the Hoedjiespunt GraniteG1 (light coloured foreground) towards the darker Saldanha Quartz Porphyry G2 (distance)	Mussel shell beach at the contact between the G1 and G2 granites, Bomgat	Dark jointed outcrops of the G2 granite, Bomgat	Sharp planar contact between the G2 (left) and G1 granites, Bomgat

The Bomgat is a sea cave eroded at the unconformity between the granite basement and Pleistocene cover	The boulder bed developed at the base of the cover sequence is composed of G2 granite cobbles and a matrix cemented by brown phosphorite, Bomgat	Megan explains the origin of the Bomgat and the stratigraphic significance of its exposures	The Hoedjiespunt Peninsula provides a view across Saldanha Bay to the steel works

The extinct Cape bear guides the way to the Langebaan Fossil Park	The fossil park is established in the old open workings of a phosphate mine	Excavations in a pavement within the phosphate ore reveals a spectacular assemblage of fossil mammal bones	Fossil jawbone complete with teeth of a Miocene giraffe like animal (Sivathere), Langebaan Fossil Park

Arcuate ridge of resistant sandstone strata at Piekenierskllof Pass	Russell explaining the stratigraphy and structure of the Cape Supergroup at Piekenierskloof Pass	Close up the coarse conglomerates of the Piekenierskloof Formation	Stratigraphy of the upper part of the Table Mountain Group viewed from the top of Pakhuis Pass

Megan elucidating the Table Mountain Group stratigraphy at the Pakhuis Pass viewpoint	Red sandstones of the Nrdouw Subgroup loom over the Pakhuis Pass	Quartzite dropstones in the Pakhuis Tillite	Evening fire at Sevilla Cottages, Travelers Rest Guest Farm, northern Cedarberg

Ladies night at Sevilla	The warm glow of burning Rooikrans, Sevilla	Bushman motifs ensconced in the Sevilla cottages	Seen in the Cedarberg at Sevilla

View east over the Doring Valley from the road to Wuppertal, northern Cedarberg	Classic Bokkeveld scenery across the Doring valley, with mesas capped with resistant sandstones	Bokkeveld Group strata overlooking the Doring River	Shale - sandstone cycles of the Bokkeveld Group, Botterkloof Pass

Transition zone between shale (below) and sandstone in a typical Bokkeveld coarsening upwards cycle, Botterkloof Pass	Dropstones in finely laminated glacial shale, Dwyka Tillite Formation, Oorlogskloof	View down onto thin laminae of glacial shale draped over a dropstone, Dwyka Tillite, Oorlogskloof	Geological Society plaque at the Oorlogskloof glacial pavement

Grooves cut by ice into unconsolidated sand overlying the Nardouw Subgroup, Oorlogskloof glacial pavement	Slump structures preserved in the grooved sands, Oorlogskloof glacial pavement	Nieuwoudtvile Waterfall, Nardouw Subgroup sandstones unconformably overly steeply dipping Malmesbury Group	Cascades above the main falls, Nieuwoudtville Falls

Edge of the main falls, Nieuwoudtville Falls	Descending Van Rhyns Pass down the western escarpment	Thin sequence of Nardouw Subgroup sandstone strata cap the escarpment at Van Rhyns Pass	Sneeuwkop lloking down on Citrusdal, Cedarberg

Snow mantled Michells Peak towers high above the fertile Ceres Basin	Road construction provided this large cut in the Bokkeveld Group shales at the top of Gydo Pass	Fossil hunting in the Bokkeveld Group shales at Gydo Pass	Ancient Silurian Brachipod fossil revealed in the Bokkeveld shales, Gydo Pass

Snow covering the Skurweberg	Irregular fold in Witteberg strata, Karoopoort	Witteberg Group dip slopes examined by students in Karoopoort	Coarse textured Dwyka Tillite exposed at the north end of Karoopoort

Winter scene in the Hex River Mountains	Stretched Brachiopd fossil in deformed Bokkeveld shales, Burgers Pass	Elongated Brachiopod fossil showing significant strain, Bokkeveld shales, Burgers Pass	Vertical Nardouw Subgroup srtata in Cogmans Kloof

Lustrous sheen from mica in the phyllitic schists of the Malmesbury Grooup, Cogmans Kloof	Closely spaced kink bands in phyllitic schists, Cogmans Kloof	Rotated vertical unconformity between phyllites of the Malmesbury Group (right) and the overlying sandstones of the Peninsula Formation, Cogmans Kloof	Final group photo at the Cogmans Kloof unconformity