Results 51 to 60 of about 7,051 (253)

A specialized topaz-bearing rapakivi granite and associated mineralized greisen in the Ahvenisto complex, SE Finland [PDF]

Bulletin of the Geological Society of Finland, 1991
The Ahvenisto rapakivi complex is a satellite northwest of the large Wiborg rapakivi batholith in Southeastern Finland. The rapakivi rocks are surrounded by rapakivi-age gabbros, anorthosites, monzodiorites and diabases.
P. Edén
doaj   +1 more source

REE-Y-Ti-Th mineralization in the albite bearing metasomatite and metasomatized rhyolite hosted in Choghart magnetite-apatite deposit, Central Iran: Interplay of evaporitic brines, hydrothermal-magmatic fluids

Journal of Economic Geology, 2023
Macroscopic, microscopic and geochemical studies carried out on albite-bearing metasomatites and metasomatic rhyolites hosting the magnetite-apatite deposit of Chogharat indicate the presence of three generations of albite with different concentrations ...
Kiamars Hosseini, Roghayeh Zabihi Khargh, Mohammad Hossein Moradian Bafghi   +2 more
doaj   +1 more source

The Geologic Features of the Occurrence of Copper in North America [PDF]

, 1933
Copper is of such widespread natural occurrence in North America and there are so few metal-mining districts that have not contributed to its production that it is obviously necessary in any brief general treatment of the geology of the copper deposits ...
Ransome, F. L.
core  

Low-volume intraplate volcanism in the Early/Middle Jurassic Pacific basin documented by accreted sequences in Costa Rica [PDF]

, 2013
Countless seamounts occur on Earth that can provide important constraints on intraplate volcanism and plate tectonics in the oceans, yet their nature and origin remain poorly known due to difficulties in investigating the deep ocean.
Alexandre N. Bandini, Alonso-Perez, Bandini, Bandini, Bartolini, Baumgartner, Buchs, Buchs, David M. Buchs, Davis, Davis, Edgar, Foley, Fujiwara, Geldmacher, Harte, Hauff, Hillier, Hirano, Hirano, Hirose, Hoernle, Johnston, Kawakatsu, Kennet E. Flores, Kimura, Konzett, Kushiro, Legendre, Lloyd, Lloyd, Machida, Matsuda, McDonough, Meer, Meschede, Michael Cosca, Natland, Natland, Nekvasil, Ni, Niu, Niu, Nokleberg, Okamura, Pavoni, Peter O. Baumgartner, Pilet, Pilet, Presnall, Prytulak, Reynolds, Smith, Sébastien Pilet, Tiepolo, Tournon, Valentine, Walter, Wessel   +58 more
core   +2 more sources

Fluid-induced high-temperature metasomatism at Rundvågshetta in the Lützow-Holm Complex, East Antarctica: Implications for the role of brine during granulite formation [PDF]

, 2018
We report new petrological, phase equilibria modeling, and fluid inclusion data for pelitic and mafic granulites from Rundvågshetta in the highest-grade region of the Neoproterozoic Lützow-Holm Complex (LHC), East Antarctica, and provide unequivocal ...
Takahashi Kazuki, Tsunogae Toshiaki, Ugwuonah Emmanuel Nwachukwu, 角替 敏昭   +3 more
core   +2 more sources

Progressively Fenitised Schist and Carbonatitic Clasts From a Metasomatic Aureole Beneath the Alkalic Dunedin Volcano, Otago, New Zealand

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 2, June 2026.
Clasts of albite‐porphyroblastic quartzofeldspathic schist, derived from the Otago Schist basement, occur within the Port Chalmers Breccia, a diatreme at the centre of the Dunedin stratovolcano, New Zealand. Schists have undergone varying degrees of replacement reactions (at temperatures of 300° to >500°C) producing hornfelses, with Ca‐ and K‐enriched ...
Alan F. Cooper
wiley   +1 more source

BANALSITE–STRONALSITE FROM SANDYITES OF THE ILMENOGORSKY MIASKITE MASSIF (SOUTH URAL) [PDF]

Минералогия, 2016
The minerals of the banalsite BaNa2(Al2Si2O8 )2–SrNa2(Al2Si2O8) stronalsite series were found for the first time in alkaline rocks of the Ilmenogorsky miaskite massif. Banalsite contains 11.97– 12.86 wt. % ВаO and 5.44–5.56 wt. % SrO.
E.V. Medvedeva, A.B. Nemov, V.A. Kotlyarov   +2 more
doaj  

Metastable Nanosized Diamond Formation from Fluid Systems [PDF]

, 2010
The model of nanosized diamond particles formation at metastable P-T parameters from fluid is presented. It explains the specific of CVD diamond synthesis gases mixtures and hydrothermal growth of diamond at low P-T parameters as well as it explains the ...
Sergei Simakov
core   +2 more sources

New Magnetite Reference Material for SIMS δ18O Measurements and a Study of Precision and Accuracy Due to Crystal Orientation Effects

Geostandards and Geoanalytical Research, Volume 50, Issue 2, Page 391-406, June 2026.
Key Points A new magnetite reference material (PF21mt) is available for δ18O measurements by SIMS. Reproducibility of measurement results in two laboratories suggest orientation bias of ±2‰ (2s) at 20 keV. Repeatability improves to ±1‰ (2s) when using a 13 keV protocol, suggesting reduced orientation bias. In situ isotope ratio measurements provide the
Michelle Ulrich, Daniela Rubatto, Maria Rosa Scicchitano, Benita Putlitz, Thomas Bovay   +4 more
wiley   +1 more source

Combustion and Pyrolysis EA‐IRMS Techniques to Determine the δ2H of Diamonds

Rapid Communications in Mass Spectrometry, Volume 40, Issue 10, 30 May 2026.
ABSTRACT Rationale Diamonds are generally considered to be metasomatic minerals originating from the Earth's mantle. They formed through the interaction of carbon‐bearing fluids or melts with the surrounding deep lithology. Most knowledge about the formation of diamonds comes from studying their mineral inclusions or stable isotopes.
François Fourel, Christophe Lécuyer, Emilie Thomassot, Etienne Deloule, Charles Ojeimi   +4 more
wiley   +1 more source