Results 11 to 20 of about 501 (102)
Geosciences, 2019 A composite lamprophyre dyke from the Central Bohemian Dyke Swarm (Czech Republic) shows both indications of magma free flow (normal magnetic fabric with magnetic foliation and lineation parallel to the dyke plane) as well as those of forcefully driven ...
František Hrouda +4 more
doaj +2 more sources
Garnet from East Ongul Island in the Antarctic Region [PDF]
Antarctic Record, 1961 The sample was collected by Prof. Torii of Chiba University. Its colour is reddish brown and translucent and it forms a somewhat elongated crystal. It shows a few cracks and is brittle. Observed under the microscope, the greater part of the thin sections
Eiichi MINAMI +2 more
doaj +3 more sources
Mineralogy and Petrology, 2022 International audienceLate to post-orogenic lamprophyres of the European Variscides attest variable compositions of the mantle beneath the structural zones of the belt.
A. Pouclet, J. Bardintzeff, H. Bellon
semanticscholar +2 more sources
Re-appraisal of Johnstonotite [PDF]
, 1967 Johnstonotite is a mixture of spessartite and ...
RJ Ford (17324023)
core +3 more sources
Melanite from the endoskarn of a spessartite dyke intruding into the Kinshozan limestone in Ogaki City, Gifu PrefectureA spessartite dyke that intruded into the Permian Kinshozan limestone formed endoskarn that is rich in melanite, along with clinopyroxene and apatite, in a matrix of secondary calcite, thomsonite, stilbite, heulandite and apophyllite. Garnet grains, ranging in size from 0.5 to 3 mm, have dark brown cores and pale to colorless mantles. Detailed analysis
SUZUKI, Kazuhiro +2 more
openaire +2 more sources
Geochemistry, Geophysics, Geosystems, Volume 24, Issue 11, November 2023., 2023 Abstract The iconic volcanoes of the Cascade arc stretch from Lassen Volcanic Center in northern California, through Oregon and Washington, to the Garibaldi Volcanic Belt in British Columbia. Recent studies have reviewed differences in the distribution and eruptive volumes of vents, as well as variations in geochemical compositions and heat flux along ...
Penny E. Wieser +3 more
wiley +1 more source
Geochemistry, Geophysics, Geosystems, Volume 24, Issue 4, April 2023., 2023 Abstract Accreted basaltic rocks are expected to provide information on intraplate volcanism in the oceans. Basaltic rocks, originating from mid‐ocean ridges, plateaus, and seamounts, have been reported from exhumed accretionary complexes. However, basaltic rocks related to petit‐spot volcanism remain poorly documented.
Ginta Motohashi +3 more
wiley +1 more source
Journal of the Geological Survey of Brazil, 2022 The Serra do Navio manganese deposit in the Amapá State, Eastern Guiana Shield, northernmost Brazil, had reserves of high-grade oxide ores exhausted, after the production of 33 million tonnes, assaying more than 45% Mn.
Wilson Scarpelli
doaj +1 more source
Tectonics, Volume 42, Issue 4, April 2023., 2023 Abstract Structures associated with Ediacaran‐Ordovician alkaline magmatism and the timing of rare earth element (REE) mineralization in the Wet Mountains, CO, were analyzed using field, geophysical, and U‐Th‐Pb isotope methods to interpret their tectonic setting in the context of previously proposed rift models. The Wet Mountains are known for thorium
Benjamin P. Magnin +2 more
wiley +1 more source
Composition and Morphological Analysis of MnO–SiO2–Al2O3 Inclusions during Solidification of Steel
steel research international, Volume 93, Issue 10, October 2022., 2022 Herein, morphological and compositional changes of MnO–SiO2–Al2O3 inclusions during solidification and cooling of actual steels are experimentally investigated. During solidification, Mn, Si, and O enrichment in the residual liquid phase leads to the formation of new inclusions with lower Al2O3 concentrations, indicating that microsegregation plays an ...
Jonah Longaquit Gamutan +2 more
wiley +1 more source