Results 11 to 20 of about 133 (115)
Reassessing southern African silcrete geochemistry: implications for silcrete origin and sourcing of silcrete artefacts [PDF]
Earth Surface Processes and Landforms, 2020 AbstractA synthesis of the geochemistry of silcretes and their host sediments in the Kalahari Desert and Cape coastal zone, using isocon comparisons, shows that silcretes in the two regions are very different. Kalahari Desert silcretes outcrop along drainage‐lines and within pans, and formed by groundwater silicification of near‐surface Kalahari Group ...
John A. Webb, David J. Nash
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Heat treatment as a universal technical solution for silcrete use? A comparison between silcrete from the Western Cape (South Africa) and the Kalahari (Botswana). [PDF]
PLoS One, 2017 Heat treatment was one of the first transformative technologies in the southern African Middle Stone Age (MSA), with many studies in the Cape coastal zone of South Africa identifying it as an essential step in the preparation of silcrete prior to its use in stone tool manufacture. To date, however, no studies have investigated whether heat treatment is
Schmidt P +4 more
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Heat treatment of Kalahari and Cape silcretes: impacts upon silcrete chemistry and implications for geochemical provenancing [PDF]
Archaeological and Anthropological Sciences, 2019 Recent studies in southern Africa and eastern Australia have demonstrated the feasibility of using a geochemical fingerprinting approach to determine the source locations from which silcrete raw materials were procured prior to their use in stone tool manufacture.
David J. Nash +2 more
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Geosphere, 2022 Silcretes have long been recognized as modern and ancient duricrusts, but more recently also as silicified layers precipitated at groundwater tables, termed groundwater silcrete. However, the silica sources, transport mechanisms, and precipitation processes of groundwater silcrete are not well understood, and models are limited to the near-surface ...
David G. Lowe +3 more
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Silcretes of Central Australia [PDF]
Nature, 1964 THE widespread occurrence in central Australia of silcrete which there caps numerous mesas and forms extensive stony pavements on the dissection slopes below them has long awaited a satisfactory explanation. A recent recording1 of the nature and disposition of certain lateritic and desertic soils, taken in conjunction with the location of major ...
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Silcrete: an Australian perspective
Australian Journal of Earth Sciences, 2017 ABSTRACTWe know how most rocks are formed. Silcrete is something of an enigma, for although there are many interpretations of the origins of individual silcrete bodies, such as those in the Paris Basin, England, Botswana and central Australia, an overarching hypothesis capable of explaining all occurrences is still to be found.
Taylor, G, Eggleton, Richard
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Titania in Australian massive silcretes
Australian Journal of Earth Sciences, 2017 ABSTRACTSelected silcretes formed by cementation of stream sediments and having >90 wt% SiO2, have been examined optically and by scanning electron microscopy. Such silcretes have quartz framework grains cemented by a plasma of quartz and anatase. Both the plasma quartz and the anatase are euhedral where they line cavities in the silcrete.
Eggleton, Richard, Taylor, G
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Sedimentology, EarlyView.ABSTRACT The Triassic succession of the northern North Sea comprises a series of interbedded sandstones, mudstones and conglomerates deposited under a fluctuating arid to semi‐humid climate regime, which are often difficult to correlate regionally due to differing lithostratigraphic schemes and poor age control. Despite existing regional studies on the
Riccardo Sordi +3 more
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Beach Gold and Heavy Mineral Concentrates on Tiwai Spit Gravel Strand Plain, Southland, New Zealand
New Zealand Journal of Geology and Geophysics, Volume 69, Issue 3, September 2026.The Holocene Tiwai Spit on Foveaux Strait is a 12 km by 2 km gravel‐dominated strand plain, ∼10 m above present sea level. Gravel clasts are dominated by well‐rounded quartz cobbles, pebbles and granules derived from Otago Schist 200 km to the north in evolving river drainage systems during late Cenozoic.
Marshall Palmer, Dave Craw
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From Highlands to Henge: Refining the Provenance and Transport Pathways of Stonehenge's Altar Stone
Journal of Quaternary Science, Volume 41, Issue 6, Page 888-895, August 2026.ABSTRACT The Altar Stone, the 6000 kg central sandstone megalith at Stonehenge in southern England, is suggested to have originated from the Orcadian Basin in northeast Scotland, some 700 km away. However, its source location within this large basin remains unresolved and its mode of transport uncertain.
Anthony J. I. Clarke +8 more
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