Palaeomagnetic and synchrotron analysis of >1.95 Ma fossil-bearing palaeokarst at Haasgat, South Africa
Palaeomagnetic analysis indicates that Haasgat, a fossil-bearing palaeocave in the Gauteng Province of South Africa, is dominated by reversed magnetic polarity in its oldest, deepest layers and normal polarity in the younger layers. The presence of in-situ Equus specimens suggests an age of less...
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| Format: | Article |
| Language: | English |
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Academy of Science of South Africa
2014-03-01
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| Series: | South African Journal of Science |
| Subjects: | |
| Online Access: | https://www.sajs.co.za/article/view/3741 |
| _version_ | 1818540557849329664 |
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| author | Andy I.R. Herries Peter Kappen Anthony D.T. Kegley David Patterson Daryl L. Howard Martin D. de Jonge Stephany Potze Justin W. Adams |
| author_facet | Andy I.R. Herries Peter Kappen Anthony D.T. Kegley David Patterson Daryl L. Howard Martin D. de Jonge Stephany Potze Justin W. Adams |
| author_sort | Andy I.R. Herries |
| collection | DOAJ |
| description | Palaeomagnetic analysis indicates that Haasgat, a fossil-bearing palaeocave in the Gauteng Province of
South Africa, is dominated by reversed magnetic polarity in its oldest, deepest layers and normal polarity in
the younger layers. The presence of in-situ
Equus
specimens suggests an age of less than ~2.3 Ma, while
morphological analysis of faunal specimens from the ex-situ assemblage suggests an age greater than
1.8 Ma. Given this faunal age constraint, the older reversed polarity sections most likely date to the beginning
of the Matuyama Chron (2.58–1.95 Ma), while the younger normal polarity deposits likely date to the very
beginning of the Olduvai Sub-Chron (1.95–1.78 Ma). The occurrence of a magnetic reversal from reversed
to normal polarity recorded in the sequence indicates the deposits of the Bridge Section date to ~1.95 Ma.
All the in-situ fossil deposits that have been noted are older than the 1.95 Ma reversal, but younger than
2.3 Ma. Haasgat therefore dates to an interesting time period in South African human evolution that saw
the last occurrence of two australopith species at ~2.05–2.02 Ma (Sts5
Australopithecus africanus
from
Sterkfontein Member 4) to ~1.98 Ma (
Australopithecus sediba
from Malapa) and the first occurrence of
early
Homo
(Sk847),
Paranthropus
and the Oldowan within Swartkrans Member 1 between ~2.0 Ma and
~1.8 Ma. |
| first_indexed | 2024-12-11T21:56:57Z |
| format | Article |
| id | doaj.art-c22f36a2e9924d14a0eb9d03785a57e3 |
| institution | Directory Open Access Journal |
| issn | 1996-7489 |
| language | English |
| last_indexed | 2024-12-11T21:56:57Z |
| publishDate | 2014-03-01 |
| publisher | Academy of Science of South Africa |
| record_format | Article |
| series | South African Journal of Science |
| spelling | doaj.art-c22f36a2e9924d14a0eb9d03785a57e32022-12-22T00:49:16ZengAcademy of Science of South AfricaSouth African Journal of Science1996-74892014-03-011103/411210.1590/sajs.2014/201301023741Palaeomagnetic and synchrotron analysis of >1.95 Ma fossil-bearing palaeokarst at Haasgat, South AfricaAndy I.R. Herries0Peter Kappen1Anthony D.T. Kegley2David Patterson3Daryl L. Howard4Martin D. de Jonge5Stephany Potze6Justin W. Adams7Australian Archaeomagnetism Laboratory, Archaeology, Environment and Community Planning, La Trobe University, Melbourne, Australia1 Physics, La Trobe University, Melbourne, Australia 2 Australian Synchrotron, X-ray Fluorescence Microprobe Beamline, Melbourne, AustraliaBiomedical Sciences, Grand Valley State University, Allendale, MI, USAAustralian Synchrotron, X-ray Fluorescence Microprobe Beamline, Melbourne, AustraliaAustralian Synchrotron, X-ray Fluorescence Microprobe Beamline, Melbourne, AustraliaAustralian Synchrotron, X-ray Fluorescence Microprobe Beamline, Melbourne, AustraliaPlio-Pleistocene Palaeontology Section, Ditsong National Museum of Natural History, Pretoria, South AfricaAnatomy and Developmental Biology, Monash University, Melbourne, AustraliaPalaeomagnetic analysis indicates that Haasgat, a fossil-bearing palaeocave in the Gauteng Province of South Africa, is dominated by reversed magnetic polarity in its oldest, deepest layers and normal polarity in the younger layers. The presence of in-situ Equus specimens suggests an age of less than ~2.3 Ma, while morphological analysis of faunal specimens from the ex-situ assemblage suggests an age greater than 1.8 Ma. Given this faunal age constraint, the older reversed polarity sections most likely date to the beginning of the Matuyama Chron (2.58–1.95 Ma), while the younger normal polarity deposits likely date to the very beginning of the Olduvai Sub-Chron (1.95–1.78 Ma). The occurrence of a magnetic reversal from reversed to normal polarity recorded in the sequence indicates the deposits of the Bridge Section date to ~1.95 Ma. All the in-situ fossil deposits that have been noted are older than the 1.95 Ma reversal, but younger than 2.3 Ma. Haasgat therefore dates to an interesting time period in South African human evolution that saw the last occurrence of two australopith species at ~2.05–2.02 Ma (Sts5 Australopithecus africanus from Sterkfontein Member 4) to ~1.98 Ma ( Australopithecus sediba from Malapa) and the first occurrence of early Homo (Sk847), Paranthropus and the Oldowan within Swartkrans Member 1 between ~2.0 Ma and ~1.8 Ma.https://www.sajs.co.za/article/view/3741biochronologyX-ray flourescencesynchrotron radiation;ironprimate fossilsmagnetostratigraphy |
| spellingShingle | Andy I.R. Herries Peter Kappen Anthony D.T. Kegley David Patterson Daryl L. Howard Martin D. de Jonge Stephany Potze Justin W. Adams Palaeomagnetic and synchrotron analysis of >1.95 Ma fossil-bearing palaeokarst at Haasgat, South Africa South African Journal of Science biochronology X-ray flourescence synchrotron radiation; iron primate fossils magnetostratigraphy |
| title | Palaeomagnetic and synchrotron analysis of >1.95 Ma fossil-bearing palaeokarst at Haasgat, South Africa |
| title_full | Palaeomagnetic and synchrotron analysis of >1.95 Ma fossil-bearing palaeokarst at Haasgat, South Africa |
| title_fullStr | Palaeomagnetic and synchrotron analysis of >1.95 Ma fossil-bearing palaeokarst at Haasgat, South Africa |
| title_full_unstemmed | Palaeomagnetic and synchrotron analysis of >1.95 Ma fossil-bearing palaeokarst at Haasgat, South Africa |
| title_short | Palaeomagnetic and synchrotron analysis of >1.95 Ma fossil-bearing palaeokarst at Haasgat, South Africa |
| title_sort | palaeomagnetic and synchrotron analysis of 1 95 ma fossil bearing palaeokarst at haasgat south africa |
| topic | biochronology X-ray flourescence synchrotron radiation; iron primate fossils magnetostratigraphy |
| url | https://www.sajs.co.za/article/view/3741 |
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