Course Handbook South African Field Course Cape
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COURSE HANDBOOK SOUTH AFRICAN FIELD COURSE Offered through AHKR institute, University of Bergen CAPE TOWN SOUTH AFRICA 2009 Compiled by Prof. Christopher Henshilwood & Karen van Niekerk 1 CONTENTS Description Page Part 1: Introduction to the Cape, South Africa Part 2: Geology and Palaeo-environment of the De Hoop region Part 3: Ethnohistory of the southern Cape Part 4: Holocene Archaeology of the Southern Cape Part 5: Mammals & Reptiles Part 6: Shellfish & Fish Part 7: Cultural artefacts Part 8: Method of Excavation Part 9: Recommended Reading List 2 Part 1: Introduction Brief History & Prehistory of the Western Cape People have occupied the Western Cape for more than a million years; hence the region boasts a rich archaeological past. For the last 100,000 years or so it was probably the home of San (Bushmen) hunter gatherers. The San left a rich heritage of rock paintings portraying their religious beliefs but also a pictorial account of their world, including the arrival, about 2000 years ago, of Khoekoe herders with sheep and cattle. Because the Western Cape is a winter rainfall area it was unsuited to the summer crops of Bantu speaking agro-pastoralists and when the Dutch East India Company established a refreshment station at the Cape in the 1600s it was occupied only by the San and Khoe. In their art, the San depicted the arrival of the Dutch as well. However, these indigenous people of ancient descent could not compete with the technology of European settlers. In time, they lost their long-held access to grazing and hunting land and by the early 1700's, decimated by poverty and disease; most laboured in the employ of the DEIC or local farmers. Today the region is still populated by descendants of the Khoisan, but also those of European and Asian settlers and slaves, and more recently by people from all over Africa. It makes for a melting pot of cultures and a fascinating travel destination. De Hoop Nature Reserve A 2 hour drive east of Cape Town brings us to the spectacular De Hoop Nature Reserve. Both a land and marine reserve it covers 60,000 ha (146,000 acres). Here we will be based at the Potberg Environmental Education Centre. The rugged coastline changes from massive white sand dunes to weird rock formations sculpted by wind and water to endless miles of empty white beaches. Inland the habitat is equally diverse with limestone hills, a vast inland vlei (lagoon) and rocky mountain. Rare or endangered animal species in the reserve include the Bontebok and Cape Mountain Zebra. Other animals you may see are eland, the Cape clawless otter, baboons, rock dassies and the occasional rooikat (caracal). The flora and fauna are impressive too – the fynbos floral kingdom dominates with 1500 species of plants in the reserve alone – also 86 species of mammal, 260 different birds, 14 amphibian and 50 reptile species. The reserve is particularly known for its bird population many of which - such as the endangered Cape oystercatcher - breed within the reserve. However, it's not only now that people appreciate the bountiful nature of the southern Cape. Spectacular caves filled with rich archeological deposits and ancient shell middens dot the De Hoop coastline telling us that hunter gatherers visited this area for more than 100,000 years. Bones and shells are now the only remains of past meals but they tell us people hunted and collected from a wide range of animals that include large and small antelope, tortoises, hares, hyraxes, fish and shellfish. The Potberg Environmental Education Centre The headquarters of the field school are at Potberg on the eastern side of De Hoop Nature Reserve. This is about half an hour’s drive from the Vaalkrans Shelter archaeological site we will be excavating. Due to the rugged terrrain and rough roads we need to use 4x4 vehicles for all our fieldwork. Accommodation is comfortable in a large converted farmhouse. The original Cape Dutch thatched homestead was built in the late 1800s by Anders Ohlsson. Potberg will be our base for 5 weeks. During 3 week days we will leave from here for the excavation site or for field training and return in the evenings. Over weekends you will be free to write up your notes, relax or go for walks. Shopping excursions to the local village are only on Saturday mornings. The Potberg area is steeped in history. Early indigenous people were attracted by the supply of fresh water and the plentiful game. Potberg has many interesting features, one being the San (Bushman) painting in the cave above the homestead. The nearby vulture valley and “vulture restaurant” is another unique feature, visible from the Klipspringer trail which leads around the mountain from Potberg. Cape vultures can often be seen soaring overhead, either on their way out to forage or returning to the valley. Management of De Hoop and Potberg The Potberg Environmental Education Centre and De Hoop Nature Reserve is state property managed by Cape Nature, a local government conservation body . SAfCO hires the facilties at Potberg and holds an excavation permit for the Vaalkrans site issued by Heritage Western Cape (HWC): The mission of Cape Nature Conservation is the conservation of the Western Cape's unique natural heritage in partnership with all its people, for the welfare, advantage and enjoyment of present and future generations. Their vision is to strive to become a world leader in conservation. At SAfCO we aim to instill in all our students a sense of wonder yet understanding of this unique natural heritage by spending many days walking through this landscape and learning about its many wonders. 4 Part 2: Geology and Palaeoenvironment of the De Hoop region The point is that we simply cannot assume that Holocene environments in South Africa were unchanging or identical. Instead we must allow that the environment was a variable parameter in any model of Later Stone Age economy or ecology (Butzer 1974:37) Bedrock Topography The southern Cape physiographic region includes three distinct elements: the Cape Folded Belt mountains, the Coastal Foreland and the Great Karoo Basin, which lies between the Folded Belt and the South African Plateau. Between Cape Agulhas and Mossel Bay, Palaeozoic deposits comprise a basement of folded and faulted sediments of the Cape Supergroup. Table Mountain Group sandstones dipping in a southerly direction outcrop on the coast at various points in the De Hoop Reserve. These are on the southern limb of an overturned syncline and are succeeded by Bokkeveld shales a short distance north of the coast. Contact between the Table Mountain Group and Bokkeveld shales is consistently in a west- south-west direction. Table Mountain Group sandstones re-occur in the anticline of the Langeberg to the north of De Hoop. Generally the bedrock is surf-cut to form a smooth, and in places stepped, surface plain that dips seawards by approximately 6 m per km. Echograms show that while the Bokkeveld shales are easily plained to a relatively smooth surface, sandstones of the Table Mountain Group may produce highly irregular topography and major bedrock depressions. Cenozoic Lithostratigraphy A suite of Cenozoic sediments, known as the Bredasdorp Group, overly the marine peneplain and extend for approximately 15 km inland. These facies record a number of changes in sea levels in this area and reflect the variations in the volumes of sea water locked up in the ice caps during glacial and inter-glacial periods. The Bredasdorp Group consists of a succession of limestones, sandy limestones, sandstones and conglomerates and can be divided into six different formations. Soil classification of the Cenozoic has divided the calcareous, chiefly aeolian deposits into three sets ranging from A3 (oldest) to A1 (youngest). Outliers of iron stained, quartzose sands of the Knysna Formation which overly bedrock are exposed at a number of locations. In many places the De Hoop Vlei Formation lies directly on bedrock and forms the base unit of the calcrete-capped calcareous A3 type sediments. The Mio/Pliocene De Hoop Vlei Formation is characterised by a shelly conglomerate layer, low-angle marine sands and bioturbated glauconite sand. A feature of this sequence is rare sharks’ teeth. The Wankoe Formation is an aeolian facies of Mio/Pliocene age which volumetrically comprises the bulk of the Bredasdorp Group and may be up to 300 m thick in places. It is typified by regressional coastal calcarenite dunes made up of broken shelly material and well rounded quartz grains with glauconite visible in the cross-bedded aeolianite. Advanced pedogenesis of this A3 sub-unit produces the terra rossa soils which are widely exposed on the coastal plain particularly on dissected slopes and in gorges. 5 Sediments of the younger Rooikrans Formation, termed A2 are comprised of a basal pebble layer and an overlying shelly quartzose sand and are of Late Pleistocene age, possibly around 125,000 years old. Vegetated and semi-consolidated dune sands which form a narrow band along the De Hoop coastline form the Waenhuiskrans Formation. These aeolianites are attributed to increased aeolian activity during the Late Pleistocene transgression about 20,000 years ago when the coastline was situated at the present 130 m isobath on the Agulhas Bank. Outcrops may be up to 60 m thick. Partially-vegetated unconsolidated dunes, often mobile, mappable as A1 sediments, occur on the coast at De Hoop. Mapped as A1 sediments these Holocene coastal dunes have been designated as the Witzand Formation. Formation Description Age Witzand (A1) Unconsolidated wind-blown Holocene dunes Waenhuiskrans (A1) Semi-consolidated aeolianite Pleistocene Rooikrans (A2) Shelly quartzose sand and Pleistocene conglomerate Wankoe (A3) Consolidated aeolianite Mio/Pliocene De Hoopvlei (A3) Shelly quartzose sand and Mio/Pliocene oyster-bearing conglomerate Geological sequence of the Bredasdorp Group Cenozoic sediments Calcretes Older calcretes and calcarenites of the Bredasdorp Formation underlie most of the aeolianites of the Holocene Witzand Formation at De Hoop.