Results 51 to 60 of about 26,858 (250)

Sourcing obsidian artefacts from Early Neolithic sites in South-Central Romania

Materiale și Cercetări Arheologice, 2019
Portable X‐ ray fluorescence spectroscopy (pXRF) was used to reveal the chemical signatures of 60 obsidian artefacts from two Early Neolithic sites in the Muntenia region of southern Romania – Uliești in Dâmbovița County and Măgura – Buduiasca in ...
Boroneanț, A., Mirea, P., Ilie, A., Bonsall, C.   +3 more
doaj   +1 more source

Cryptotephra from a ~120 ka Tondano eruption in a sediment core from Lake Towuti (Indonesia)

Journal of Quaternary Science, EarlyView.
ABSTRACT Southeast Asia is one of the most volcanically active regions in the world, yet their long‐term eruptive history has been comparatively little studied. In particular, little work has explored the potential of sedimentary archives to record distal cryptotephra, which may help in identifying some of the region's larger Quaternary eruptions. Here,
Jinheum Park, Christine S. Lane, Clive Oppenheimer, Céline‐Marie Vidal, Christina J. Manning, Francesca Forni, Hendrik Vogel, Satria Bijaksana, James M. Russell   +8 more
wiley   +1 more source

A rheological investigation of vesicular rhyolite [PDF]

, 1992
The rheology of vesiculating rhyolitic systems exerts a strong control on the transport of silicic magmas in the subvolcanic to volcanic environments. We present here an investigation of vesiculating and vesiculated rhyolites using dilatometric methods ...
Bagdassarov, Nikolai, Dingwell, Donald B.   +1 more
core   +1 more source

The exploitation of obsidian in the Central Plateau of Santa Cruz, Argentina: Results from La María and Cerro Tres Tetas and a regional perspective

Journal of Lithic Studies, 2016
La María and Cerro Tres Tetas archaeological localities are located in the Central Plateau, in the province of Santa Cruz, Argentine Patagonia. This area presents abundant lithic raw materials of very good quality for knapping including flint, chalcedony
Manuel Enrique Cueto, Ariel David Frank, Fabiana Skarbun   +2 more
doaj   +1 more source

A reanalysis of the Tikopia obsidians

Archaeology in Oceania, 2010
AbstractIn 1982 an initial sourcing of 13 obsidians and volcanic glasses from Tikopia in the Solomon Islands suggested that four specimens came from Bismarcks sources, with Talasea in West New Britain being the most likely, and the rest came from the Banks Islands.
Spriggs, Matthew, Bird, Roger, Ambrose, Wallace   +2 more
openaire   +2 more sources

Lithic analysis in African archaeology: Advances and key themes

Archaeometry, EarlyView.
Abstract Stone artifacts (lithics) preserve for extended periods; thus they are key evidence for probing the evolution of human technological behaviors. Africa boasts the oldest record of stone artifacts, spanning 3.3 Ma, rare instances of ethnographic stone tool‐making, and stone tool archives from diverse ecological settings, making it an anchor for ...
Deborah I. Olszewski, Amanuel Beyin, Justin Pargeter   +2 more
wiley   +1 more source

Frequency Dependent Rheology of Vesicular Rhyolite [PDF]

, 1993
Frequency dependent rheology of magmas may result from the presence of inclusions (bubbles, crystals) in the melt and/or from viscoelastic behavior of the melt itself.
Angell, Bagdassarov, Barnes, Bentley, Berckhemer, Brawer, Cashman, Chen, D. B. Dingwell, Dattagupta, Dingwell, Dingwell, Hopkins, Jäckle, Jäckle, Kampfmann, Khitarov, Moynihan, N. S. Bagdassarov, Nguyen, Nowick, Philippoff, Prud'homme, Ripley, Schowalter, Sinning, Stein, Sura, Webb   +28 more
core   +1 more source

Positron Annihilation in Obsidians

Acta Physica Polonica A, 1995
Positron lifetime spectra as well as one-dimensional angular correla- tions of positron annihilation radiation were measured at room temperature for samples of rhyolitic obsidian coming from Iceland, Italy and Armenia. The samples were of different age. One specimen (originating from Iceland) . was relatively young, formed in 1980. The others were much
J. Chojcan, M. Sachanbiński
openaire   +2 more sources

What can lithics tell us about hominin technology's ‘primordial soup’? An origin of stone knapping via the emulation of Mother Nature

Archaeometry, EarlyView.
Abstract The use of stone hammers to produce sharp stone flakes—knapping—is thought to represent a significant stage in hominin technological evolution because it facilitated the exploitation of novel resources, including meat obtained from medium‐to‐large‐sized vertebrates. The invention of knapping may have occurred via an additive (i.e., cumulative)
Metin I. Eren, Stephen J. Lycett, Michelle R. Bebber, Alastair Key, Briggs Buchanan, Emma Finestone, Joseph Benson, Rebecca Biermann Gürbüz, Adela Cebeiro, Roman Garba, Anne Grunow, C. Owen Lovejoy, Danielle MacDonald, Erica Maletic, G. Logan Miller, Joseph D. Ortiz, Jonathan Paige, Justin Pargeter, Tomos Proffitt, Mary Ann Raghanti, Teal Riley, Jeffrey I. Rose, David M. Singer, Robert S. Walker   +23 more
wiley   +1 more source

Obsidian expansion kinetics

IOP Conference Series: Materials Science and Engineering, 2020
Abstract According to the modern terminology, the term «perlite» means natural glassy mountainous rock that has the expansion feature when heated causing high porous pumice-like material. Scientifically, in the first place, perlite (containing different quantities of water) itself that is hydrated volcanic glass, in the second place ...
A. Safaryan, T. Sarkisyan, T. Paytyan, A. Baghdagyulyan   +3 more
openaire   +2 more sources