Heritage Cases

The analysis proposed forms a component of a larger and comprehensive investigation of the stratigraphy of the Sterkfontein Caves palaeoanthropological site. Over the last four years, Ron Clarke and the applicant (D Stratford) have developed collaborations with leading experts in karst stratigraphy and chemical analysis in France and use their skills to augment our research at the site. This permit relates to the stratigraphic investigation of three important areas of the Sterkfontein Caves. The first is the Jacovec Cavern. This hominin-bearing chamber contains several deposits initially dated to over three million years in age (Partridge et al., 2003). However, the stratigraphy and formation of these deposits has never been clarified. Renewed sampling of the hominin-bearing deposit in the chamber yielded several hominin fossils and add to the already intriguing assemblage which shows an interesting mix of primitive and derived traits. The stratigraphic analysis is of fundamental importance to understanding the relationships between the faunal and hominin assemblages of the Jacovec and the more established Australopithecus-bearing Member 2 and Member 4 deposits. A successful grant from the Leakey Foundation has provided the funds for a details stratigraphic study of this chamber which will include sediment micromorphology and XRF/PIXE chemical analysis, and particle size analysis. The micromorphological analysis will be conducted by Dr. Richard Maire, at the University of Bordeaux, a leading expert in cave sediments. The PIXE chemical analysis will be conducted by Dr. Richard Ortega at the same institution.10 samples will be taken from the Jacovec. The second area of focus relevant to this permit is the Member 4 and Member 5 boundary. Identification and mapping of this boundary is of key importance to understanding the transition from Australopithecus, found in Member 4, and the Oldowan stone tool assemblage, found in Member 5, which is not associated with Australopithecus. The two deposits have been linked to distinct environmental conditions, taphonomic agents and sediment formation processes, but the exact nature of the boundary between the deposits has been controversial. This has led to conflicting interpretations of fossils in the area of the boundary and their ages. The most notable example being the StW 53 specimen. This specimen was originally claimed by Tobias and Hughes to be Homo habilis due to its presumed association with the stone tools found in the nearby Member 5. A renewed stratigraphic study by Ron Clarke demonstrated that StW 53 came from a remnant of Member 4, was therefore older, and was more likely to be an Australopithecus africanus (Kuman & Clarke, 2000). The boundary between the deposits is complex and initial mapping suggests vertical sediment contacts associated to localised erosion and re-karstification in the western part of Member 4, into which Member 5 filled. This deserves greater stratigraphic clarification and higher resolution analyses. In conjunction with renewed and detailed 3D mapping of this area of the site, micromorphology of the deposit bodies, sediments contacts and stratigraphic features will yield a high resolution microscopic interpretation of the formation processes in this important area of the site. 10 Samples will be taken by the applicant (D Stratford) and Dr. Laurent Bruxelles and micromorphological analysis will be conducted by Dr. Richard Maire and PIXE chemical analysis by Dr. Richard Ortega. The third area of interest for specialist sediment sampling and micromorphological analysis is the Milner Hall excavations conducted by the applicant (D Stratford). The main excavation, STK-MH1, uncovered 4 deposits which represent depositional events spanning the entire sedimentation history of the caves. Here, the soft sediments are easily sampled and have already been researched extensively and are currently being published. At the time of original research, an expert cave micromorphologist was not available and so now an application to take new samples and have them analysed is being submitted. Of particular interest are the deposit contacts and erosional surfaces identified in the excavations. Micromorphological analysis of these features will clarify the specific and complex range of deposit formation processes working in the caves and enable perspectives on faunal assemblage accumulation processes and the influence of post-depositional processes on the fossils. 10 Samples will be taken by the applicant (D Stratford) and Dr. Laurent Bruxelles and micromorphological analysis will be conducted by Dr. Richard Maire and PIXE chemical analysis by Dr. Richard Ortega.