Results 1 to 10 of about 64 (59)
Knapping force as a function of stone heat treatment [PDF]
PLoS ONE, 2022 We propose a quantitative framework for understanding the knapping force requirements imposed by different raw materials in their unheated and heat-treated states.
Klaus G. Nickel, Patrick Schmidt
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Petrological and geochemical characterisation of the sarsen stones at Stonehenge [PDF]
PLoS ONE, 2021 Little is known of the properties of the sarsen stones (or silcretes) that comprise the main architecture of Stonehenge. The only studies of rock struck from the monument date from the 19th century, while 20th century investigations have focussed on ...
David J. Nash +14 more
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The composition, geography, biology and assembly of the coastal flora of the Cape Floristic Region [PDF]
PeerJ, 2021 The Cape Floristic Region (CFR) is globally recognized as a hotspot of plant diversity and endemism. Much of this diversity stems from radiations associated with infertile acid sands derived from sandstones of the geologically ancient Cape Fold Belt ...
B. Adriaan Grobler, Richard M. Cowling
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Late Neogene terrestrial climate reconstruction of the central Namib Desert derived by the combination of U–Pb silcrete and terrestrial cosmogenic nuclide exposure dating [PDF]
Geochronology, 2023 The chronology of the Cenozoic “Namib Group” of the Namib Desert is rather poorly understood and lacks direct radiometric dating. Thus, the paleoclimate and landscape evolution of the central Namib Desert remains imprecise, complicating the detailed ...
B. Ritter +8 more
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ChemEngineering, 2022 After subjecting Zamora building stones to accelerated ageing tests, colour changes were studied, namely: (a) freezing/thawing and thermal shock (gelifraction and thermoclasty), and (b) combination of freezing/thawing plus thermal shock and salt ...
Jacinta García-Talegón +3 more
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Gem-quality chrysoprase from Haneti-Itiso area, Central Tanzania [PDF]
Bulletin of the Geological Society of Finland, 1990 Gem-quality, apple-green, Ni-bearing chalcedonic quartz occurs as near-surface veins in silicified serpentinite in the Haneti-Itiso area, Central Tanzania.
K.A. Kinnunen, E.J. Malisa
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Mineralogical Appraisal of Sediments of Duricrust Suites and Pans around Jwaneng Area, Botswana
Journal of Applied Sciences and Environmental Management, 2009 A mineralogical investigation of duricrust suites in Letlhakeng valley, and five pans around Jwaneng in Botswana was undertaken in order to know the mineral assemblages and infer on their landscape formation. In Letlhakeng, duricrusts comprised calcretes,
JR Atlhopheng, G-I E Ekosse
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A numerical model for duricrust formation by water table fluctuations [PDF]
Earth Surface DynamicsDuricrusts are hard mineral layers forming in climatically contrasted environments. They form in tropical to arid environments and can be currently observed all around the world in areas such as Europe, Africa, South America, India, and Australia.
C. Fenske +5 more
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Boletín de la Sociedad Española de Cerámica y Vidrio, 2003 Mineralogy, chemical composition and textures of silcretes, calcretes/palustrine limestones and argillaceous beds are studied to consider the features and the genesis of fibrous-clay minerals.
Bustillo, M. A., García Romero, E.
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Archean (3.3 Ga) paleosols and paleoenvironments of Western Australia. [PDF]
PLoS One, 2023 Retallack GJ, Schmitz MD.
europepmc +1 more source