Palaeomagnetic results and new dates of sedimentary deposits from Klasies River Cave 1, South Africa

HUGO G. NAMI; JAMES FEATHERS; PALOMA DE LA PEÑA; SARAH WURZ; CARLOS A. VÁSQUEZ

SOUTH AFRICAN JOURNAL OF SCIENCE

ACAD SCIENCE SOUTH AFRICA A S S AF

Lugar: Johannesburg; Año: 2016 vol. 112 p. 51 - 63

0038-2353

Palaeomagnetic data from Klasies River main site Cave 1 (Eastern Cape Province, South Africa)are reported. Natural remanent magnetisation directions obtained from 77 oriented samples weredetermined by progressive alternating field demagnetisation methodology. Three palaeomagneticsamplings from the Witness Baulk from the Middle Stone Age (MSA) Late Pleistocene White Sandmember and the Holocene Later Stone Age (LSA) middens in Cave 1 were dated and analysed to obtainthe palaeomagnetic directions recorded in the sediments. Here we provide new optically stimulatedluminescence (OSL) dates for the White Sand Member, and new accelerator mass spectrometry (AMS)radiocarbon dates for the LSA midden of areas not previously dated. The palaeomagnetic analysistook into account rock magnetism and directional analysis. The former reveals that the main magneticcarrier was magnetite; the latter shows that characteristic remanent magnetisation of normal andanomalous directions were observed in the lower portion of the White Sand Member and LSA midden.Normal directions correspond to the palaeosecular variation record for South Africa during the LatePleistocene. On the other hand, the anomalous directions recorded in the LSA midden might representthe likely Sterno-Etrussia geomagnetic field excursion which occurred during the Late Holocene andis observed in other places on the planet. Finally, the directional data obtained are a potential tool fordiscussing the age of deposits corresponding to those periods.