Abstract
Palaeomagnetic data from a sedimentary section spanning the Holocene and terminal Pleistocene (~13 kya) from Rose Cottage Cave, eastern Free State (South Africa), are reported. The palaeomagnetic analysis took into account rock magnetism and directional analysis. The former reveals that most samples show stable single domain and superparamagnetic particles of Ti-poor magnetite and haematite. Natural remanent magnetisation directions were determined by progressive alternating field demagnetisation methodology. Directional analysis shows normal directions between samples 18 to 39 and 85 to 92; however, during the Early and Late Holocene in samples principally from RC40 to 84 ‘anomalous’ directions occurred. There is a significant westward shift in declination of ~80°, and a conspicuous fluctuating inclination in the lower part of the section during the Early Holocene at ≥9.5 kya and before ~12.0/13.0 kya. This palaeomagnetic record might become a chronostratigraphical marker for latest Pleistocene/Holocene sedimentary deposits in South Africa. Our two new accelerator mass spectrometry radiocarbon dates for the sampled deposit are 9500±50 BP and 1115±30 BP.
 Significance
 
 The study provides new accelerator mass spectrometry dates on the chronological sequence existing in Rose Cottage Cave.
 The findings contribute to the knowledge of the geomagnetic field behaviour since the terminal Pleistocene to the Late Holocene in a period spanning the last 13 000/12 000 years.
 This palaeomagnetic record might become a chronostratigraphical marker for the latest Pleistocene/ Holocene sedimentary deposits in South Africa.
Highlights
The primary goal of palaeomagnetism is retrieving past geomagnetic field (GMF) behaviour through time from geological and archaeological remains
The other significant feature is a geomagnetic excursion, that is a major deviation in the geomagnetic field behaviour that does not result in reversal
Palaeomagnetic data obtained in the fine-grained sediments from a section at Rose Cottage have mostly shown normal directions, especially between samples RC18 to RC39 and RC85 to RC92; some samples, principally from RC40 to RC84, exhibit ‘anomalous’ southward directions where wide pulses occurred at different times during the Early and Late Holocene
Summary
The primary goal of palaeomagnetism is retrieving past geomagnetic field (GMF) behaviour through time from geological and archaeological remains. For illustrations of the tool types, see previous detailed publications.[22,23,24] The Rose Cottage sedimentary fill shows a deep (more than 4 m in places) and varied stratigraphy that provides a complex sequence deposited between ~0.5 kya and about 90 kya.17(p.440, Fig.3),[19] the section sampled for palaeomagnetic research belongs to the last millennia of the Pleistocene and Holocene (Figure 2b,c). Because of the dates and the relative densities of archaeological material, Wadley17(p.440) suggested that some of the darker organic-rich layers (e.g. Pt, H and DB) were slowly deposited during periods of gentle rainfall as shallow lenses with considerable anthropogenic content, while the underlying orange sands (e.g. CM to Ja and Wa1) accumulated rapidly and with less anthropogenic material The latter were primarily formed through weathering or rock spalling of the sandstone roof and through material washed into the cave by springs, occasionally activated during protracted, heavy rains.[25]. The new date suggests that the entire Oakhurst sequence may be of greater antiquity than was previously thought
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