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2020-12-04 16:32:22   •   ID: 2224

The Acheulian of South Africa

Figure 1
The handaxes shown here come from a deeply stratified Diamond mining site in the North West Province of South Africa near Glaudina.

The handaxes are up to 20 cm large, most of them are rolled or abraded and only one was made from flint, while volcanic raw material was used for the knapping of the other specimens- a common characteristic of the South and East African ESA.

Cleavers are missing, while some hand axes have a pic-like appearance and a trihedral cross-section.

The Handaxes, except one specimen, were made by a hard-hammer technique. Only one artifact was indisputably made by LCT technology.

Figure 5 and 6 show an "Uniface" with probably a pitch of organic residues near the distal point (Figure 7). A similar LCT with probable evenmore extensive organic residues is shown in Figure 8; kindly submitted by W.H (Note that similar patterns on small ESA-Flakes from the late Lower Paleolithic Acheulian site of Revadim, Israel revealed organic residues of butchering activities-see: Revadim - C Federmann-Doebber drew my attention to this detail - thank you!

Burned bones from Swartkrans Cave in South Africa suggest that hominids systematically used fire beginning 1.0 to 1.5 Ma The artifacts may about 1 Ma old and seem to come from an already well established tradition.

If we ask for the oldest Acheulian in South Africa, there are several hotspots, that have to be considered. The first is located in the Gauteng Province, in the early hominid sites at Sterkfontein - which will the theme of a later post- see also 2227 . An age of 1,7–1,4 Ma has been published for the Sterkfontein Member 5 Acheulian.

Anyhow a new dating program revealed a date of 1,84 Ma (Granger 2015).

Figure 2
In addition early Acheulian localities have been found in the Vaal Valley. The most interesting localities of early Acheulian age in the Vaal region have been excavated at Rietputs and at Canteen Kopje.

It was early recognized, the alluvial gravels and sands of the Vaal bear extraordinary rich ESA material.

Large collections were formed by the pioneers of the South African Paleolithic Archeology such as C. van Riet Lowe and Astly Goodwin. Needles to say that the omnipresent "father of Prehistory", the Abbe Beuil, was also involved in these early activities, during several trips to South Africa.

van Riet Lowe and Goodwin tried to categorize the material into a lower, middle and upper "Stellenbosch Culture" (now called Acheulian). About the "type site" of Stellenbosch see here- 2071

All these early collections are not very informative by their poor documentation, selection bias of the "best pieces" and their unclear provenience coming from poorly documented and disturbed localities. Many of these were collected from surface scatters.

Anyhow these early pioneers soon recognized that apparently an early "Levallois like Industry"- called „Victoria West“ occurred together with rather advanced handaxes.

During these early days the term: Fauresmith“ as a transitional industry between ESA and MSA was also coined- see: 2197

In contrast to East Africa- South Africa is a region that lacks a volcanic ash stratigraphy. Therefore other methods have been established for absolute dating during the last 40 years, among them the „cosmogenic nuclide burial dating“. A good description of this method can be found in the papers of Granger (for example Granger 2008).

Archeological sites in river gravels and caves have become an important field of dating geological sediments by
Figure 3
Cosmogenic Al-26 and Be-10. Cosmogenic in this context means that several rare isotopes are produced in different rocks, among them the physico-chemical very stable quartz, when they are exposed to cosmic radiation for a while, near the ground surface.

Both isotopes have their own, specific radioactive exponential decay, and a characteristic half-life. After reaching an equilibrium in quartz grains, that were exposed to cosmic radiation in an open landscape, they are found in the mineral target at a fixed ratio.

The ratio of Al-26 and Be-10 in quartz, before geological burial is allways 6.75 : 1. If these sediments are buried, the accumulation of Cosmogenic Al-26 and Be-10 will stop if the overlaying strata are thick enough to have a nearly complete shielding effect on the samples that have to be dated.

The half-life of Al-26 (750 k.a.) is shorter than that of Be-10 (1,39Ma). Therefore the ratio between the isotopes decreases over time after burial and any measured ratio exactly corresponds with a certain burial age, without the need of any cross-check or calibration by other methods.

Regarding the half-lifes of Al-26 and Be-10, the method is widely applicable for dating Plio-Pleistocene clastic sediments. The method can be used over a timescale ranging up to 5 Ma and offers a great potential, both in Geology and Prehistoric Archaeology.

Figure 4
The calculated burial age of gravels and sediments allows the indirect dating of incorporated artifacts, under the condition that they were found in-situ and did not secondary change their position in strata that are to be dated. The method is increasingly applied not only on sediments but also directly on stone tools coated by quartz particles.

Applications include simple burial dating, applied to very deeply buried deposits such as cave sediments; complex burial dating, which can apply minimum and maximum constraints to a burial age; and isochron burial dating, which can be applied to sediment buried beneath only a few meters of overburden (Leader 2009).

Of course, and comparable with the many problems, that had and still have to resolved with C-14 dating, the cosmogenic nuclide burial dating is much more tricky than it may be suggested by the short text above.

Figure 5
Of mayor interest are several deeply stratified Early Acheulian localities at Rietputs 15, located near Windsorton, Northern Cape Province, located about 1,5 km from the modern Vaal River where excavations took place in five pits from Diamant mining, some of them were dated by cosmogenic nuclide burial dating (Kuman and Gibbon 2017).

Figure 6
Samples were taken under favorable conditions at depths from 7 to 16 m. The initial dates dates were published by Gibbon et al. (2009) for the tool-bearing gravels and ranged from 1,89 ± 0,19 to 1,34 ± 0.22 Ma but were later revised to 1,73 ± 0,16 to 1,26 ± 0,21 Ma (Leader et al. 2014).

The oldest dates in the series of five dated pits comes from Pit 1 and range between ca 1,7 and 1,2 Ma. Overall the earliest Acheulean sites beyond East Africa seem to be nearly as old as in parts of the Great Rift Valley, mainly in Ethiopia and Tansania (Kuman and Gibbon 2017).

What are the Typo-technological characteristics of the earliest South African Acheulian from the Vaal area and did it change over time?

Kuman and Gibbon recently described the technology of core flaking on an assemblage, named ACP, located near Rietputs Pit 1, with an age of ca 1,7 Ma and compared the results of the APC site with those from Pit 5, dated between 1,2-1,6 Ma (Kuman and Gibbon 2017).

Figure 7
While core reduction started opportunistic and unstructured in the earliest Acheulian strata, it became more organized over time.

Figure 8
At Canteen Kopje, an early Acheulian was dated to 1,51 Ma by Cosmogenic-nuclide burial dating, and also revealed organized core reduction strategies (Leader 2014).

The most interesting feature of this site is that the early Acheulian was buried below a stratum with Victoria West cores and a buried age estimate of approximately 1 Ma. Although the Victoria West technique follows a volumetric concept, it is certainly not Levallois sensu strictu, but an independent prepared core entity of its own signature (Kuman et al. 2017).

Large cutting tools (LCTs) for the production of Flake-Cleavers, Handaxes and Pics, made both on flakes and cobbles are the heavy duty component of the Early South African Acheulian. They show much variability, but are clearly distinctive from the preceding Olduvan.

It is impossible to date the artifacts from the Glaudina Collection, shown in this post- but they would certainly deserve a closer Evaluation, because they were found buried deep in Pleistocene deposits optimal for new dating techniques, described above.

Suggested Readings:

Shea J: Stone Tools in Human Evolution: Behavioral Differences among Technological Primates; 2017

Shea J et al. (ed.): Out of Africa I: The First Hominin Colonization of Eurasia; 2010

Shea J: Stone Tools of Eastern Africa-A Guide; 2020

M Maslin: The Cradle of Humanity: How the Changing Landscape of Africa Made Us So Smart; 2017

Surf the Blog:

see here 2174 , here 1657 , here: 2169 , here: 1715 and here: 2071