Results 51 to 60 of about 25,858 (276)

Study of Garnets in Hellenistic–Roman Jewellery From the Collections of the Archaeological Museum of Thessaloniki, Greece

Journal of Raman Spectroscopy, EarlyView.
This study presents the gemological analysis of 25 garnets from Hellenistic and Roman jewellery in the Archaeological Museum of Thessaloniki using mobile Raman spectroscopy and micro‐EDXRF. The garnets are classified into three geochemical clusters, with notable differences in distribution between Thessaloniki and Pydna, suggesting distinct trading ...
Maria Nikopoulou, Stefanos Karampelas, Evangelia Tsangaraki, Lambrini Papadopoulou, Christos Katsifas, Ioannis Nazlis, Annareta Touloumtzidou, Vasilios Melfos, Nikolaos Kantiranis   +8 more
wiley   +1 more source

Abundance and Partitioning of OH in a High-pressure Magmatic System: Megacrysts from the Monastery Kimberlite, South Africa [PDF]

, 2004
Concentrations of OH, and major and trace elements were determined in a suite of mantle-derived megacrysts that represent the crystallization products of a kimberlite-like magma at ~5 GPa and ~1400–1100°C.
Bell, David R., Moore, Rory O., Rossman, George R.   +2 more
core   +1 more source

Origin of Ophiolitic Peridotites

Journal of Geography (Chigaku Zasshi), 1989
Origin of spinel peridotites of upper mantle derivation, especially that of ophiolitic peridotites, is discussed mainly on the basis of compositional relationship between olivine (Fo content) and chromian spinel (Cr/(Cr+Al) atomic ratio=Cr* ratio). Spinel peridotites are distributed in a relatively narrow band, the olivine-spinel mantle array, on the ...
openaire   +3 more sources

Comparison of Two Methods for Determination of Rhenium and Platinum‐Group Elements in Meteorites Using On‐Line and Off‐Line Matrix Separation Modes

Geostandards and Geoanalytical Research, EarlyView.
Key Points PEEK tubing has been observed to adsorb Pd and Pt ions, resulting in significantly reduced recoveries of Pd and Pt elements. HPA‐S provides a more effective dissolution for meteorite samples than Carius tube digestion, resulting in higher mass fractions for PGE.
Yuling Zeng, Guiqin Wang, Thomas C. Meisel   +2 more
wiley   +1 more source

The response of borehole water levels in an ophiolitic, peridotite aquifer to atmospheric, solid Earth, and ocean tides

Journal of Hydrology X, 2023
Peridotite aquifers are ubiquitous on Earth, but most are in the deep-sea, and thus difficult to access. Ophiolites provide a unique opportunity to study peridotite aquifers, and the Oman Drilling Project established a Multi-Borehole Observatory in a ...
R.A. Sohn, J.M. Matter
doaj   +1 more source

THERMOBAROMETRY OF DEPLETED PERIDOTITES

Geodynamics & Tectonophysics
An assessment was made of the possibility of using olivine thermobarometry for xenoliths of depleted peridotites from the Udachnaya pipe (Yakutia), represented by 76 megacrystalline dunites and 5 megacrystalline harzburgites. Specially developed and tested method of microprobe analysis was used to determine Al and Ca microimpurities in the olivine ...
L. N. Pokhilenko, V. N. Korolyuk, N. P. Pokhilenko   +2 more
openaire   +2 more sources

Olivine fabric and microstructure in Northwest Africa (NWA) 7059 and Nova 018: Insights into ureilite deformation

Meteoritics &Planetary Science, EarlyView.
Abstract Olivine is a major constituent in ureilites and commonly defines macroscopic fabric via shape‐preferred orientation of elongate grains. In this study, we examined olivine fabric (crystallographic preferred orientation, or CPO) and microstructures in the unbrecciated olivine‐pigeonite ureilites Northwest Africa (NWA) 7059 and Nova 018 using ...
A. I. Sheen, C. K. F. Tirona, K. T. Tait, L. F. White, B. C. Hyde, S. Korchinos   +5 more
wiley   +1 more source

Gravimetric structure for the abyssal mantle massif of Saint Peter and Saint Paul peridotite ridge, Equatorial Atlantic Ocean, and its relation to active uplift

Anais da Academia Brasileira de Ciências, 2014
This paper presents gravimetric and morphologic analyses based on the satellite-derived data set of EGM2008 and TOPEX for the area of the oceanic mantle massif of the Saint Peter and Saint Paul peridotite ridge, Equatorial Atlantic Ocean.
KENJI F. MOTOKI, AKIHISA MOTOKI, SUSANNA E. SICHEL   +2 more
doaj   +1 more source

On a Diamantiferous Peridotite, and the Genesis of the Diamond [PDF]

Scientific American, 1886
The discovery of diamonds at Kimberley, South Africa, has proved to be a matter, not only of commercial, but of much geological interest. The conditions under which diamonds here occur are unlike those of any other known locality, and are worthy of special attention.
openaire   +3 more sources

Fe Oxidation State and Oxygen Isotope Composition of Diverse Metasomatized Peridotite Rocks

Terra Nova, EarlyView.
ABSTRACT Metasomatic fluids are thought to be oxidising agents that react with the surrounding mantle rocks, causing changes in the bulk Fe3+/ΣFe, their redox state, and affecting the partitioning of trace elements and the fractionation of O isotopes. Worldwide distributed metasomatized peridotites represent the ideal case study to investigate the role
Federica Benedetti, Giulia Marras, Enrico Cannaò, Gianluca Bianchini, Daniele Brunelli, Luigi Dallai, Vincenzo Stagno   +6 more
wiley   +1 more source