A5045359946- Geological and Geochemical Analysis
- Crystal Structures and Properties
- X-ray Diffraction in Crystallography
- Geochemistry and Geologic Mapping
- High-pressure geophysics and materials
- Astro and Planetary Science
- Mineralogy and Gemology Studies
- Clay minerals and soil interactions
- Geochemistry and Elemental Analysis
- Advanced Condensed Matter Physics
- Planetary Science and Exploration
- Radioactive element chemistry and processing
- Geology and Paleoclimatology Research
- earthquake and tectonic studies
- Metal Extraction and Bioleaching
- Nuclear materials and radiation effects
- Chemical Synthesis and Characterization
- Inorganic Fluorides and Related Compounds
- Solid-state spectroscopy and crystallography
- Paleontology and Stratigraphy of Fossils
- Zeolite Catalysis and Synthesis
- Crystallization and Solubility Studies
- Polyoxometalates: Synthesis and Applications
- Methane Hydrates and Related Phenomena
- Glass properties and applications
Natural History Museum
2015-2024
Museum of London
2018
German Oceanographic Museum
2009-2017
British Museum
1990-2015
American Museum of Natural History
2012-2015
Kansas State University
2013
University of Pavia
2012
The silico‑carbonatite dykes of the Huanglongpu area, Lesser Qinling, China, are unusual in that they quartz-bearing, Mo-mineralised and enriched heavy rare earth elements (HREE) relative to typical carbonatites. textures REE minerals indicate crystallisation monazite-(Ce), bastnäsite-(Ce), parisite-(Ce) aeschynite-(Ce) as magmatic phases. Burbankite was also potentially an early crystallising phase. Monazite-(Ce) subsequently altered produce a second generation apatite, which turn replaced...
Abstract The Cornubian Batholith (SW England) is an archetypal Variscan rare metal granite with potential for Li-mica mineralization. We present a petrographic, trace element and multivariate statistical study of micas from the series related hydrothermally altered units to assess role magmatic vs subsolidus processes fluxing elements (F B) on Li cycle during evolution system. mica types are as follows: (1) magmatic, which include Fe-biotite, protolithionite I phengite-muscovite most...
The magmatic garnet of seven granitic NYF (niobium–yttrium–fluorine-enriched) pegmatites from the Froland and Evje–Iveland areas in southern Norway were studied with respect to their major- trace-element composition intracrystalline distribution major minor elements. increasing average MnO/(FeO + MnO) values grains investigated reflect fractionation abyssal heavy REE muscovite rare-element pegmatites. At a crystal scale, MnO/(MnO FeO) show various trends controlled by coexisting...
The Devonian (ca. 385–360 Ma) Kola Alkaline Province includes 22 plutonic ultrabasic–alkaline complexes, some of which also contain carbonatites and rarely phoscorites. latter are composite silicate–oxide–phosphate–carbonate rocks, occurring in close space-time genetic relations with various carbonatites. Several types recognized at Kola, including abundant calcite (early- late-stage), subordinate amounts late-stage dolomite carbonatites, magnesite, siderite rhodochrosite In phoscorites...
The Skouries deposit is a platinum-group element (PGE) enriched Cu-Au porphyry system located in the Chalkidiki peninsula, Greece, with associated Ag, Bi and Te enrichment. hosted by multiple porphyritic monzonite syenite intrusions, which originated from magma chamber at depth. An initial quartz intrusion contains quartz–magnetite ± chalcopyrite–pyrite vein stockwork intense potassic alteration. cross cut set of mafic dykes quartz–chalcopyrite–bornite magnetite veins host majority Cu Au...
Abstract Pegmatite fields within granite plutons are commonly considered to have formed from residual melts of their host. This is not always true as demonstrated by the Tysfjord gneiss and its two groups pegmatites. The gneiss, exposed in a tectonic window Caledonides northern Norway, part transscandinavian igneous belt (TIB) that includes several phases granitic magmatism. In Hamarøy area (Drag-Finnøy), where most rare-element pegmatites occur, Paleoproterozoic metamorphosed Group 1...
Samples of natrocarbonatite showing various degrees alteration are preserved in an older carbonatite platform that existed before and until the 1917 explosive eruption at Oldoinyo Lengai volcano, Tanzania. The samples contain two mineral assemblages: first consists relict primary magmatic minerals: nyerereite, fluorite, apatite-(CaF), barite, magnetite khanneshite. second consist low-temperature subsolidus pirssonite, calcite, shortite, nahcolite, trona, thermonatrite, jacobsite...
Abstract We report the discovery of a unique micrometeorite, containing an exotic Al-Cu-Fe alloy composed two intermixed phases: khatyrkite (CuAl 2 ) and stolperite (CuAl) both minor Fe (<1.4 wt%). These phases are dendritic rapidly co-crystallized at binary system’s peritectic (~550 °C). The host micrometeorite is otherwise typical S-type micro-porphyritic cosmic spherule relict olivine (Fo76–90, Cr O 3 : 0.01–0.56 wt%, MnO: 0.03–0.32 wt% CaO: 0.09–0.22 wt%) cumulate layered texture....
Hydrothermal fluid evolution north of the St Austell granite, southwest England, has been studied through geochemical analysis tourmaline from a fault breccia <2 cm width within massive quartz–tourmaline rocks at Roche. Brecciated grains have overgrowths <400 μm [Fe/(Fe + Mg) = 0·31–0·99] with four chemically distinct zones (1–4, towards margins). Variations in overgrowth composition were caused by episodic mixing between Mg-, Al-rich magmatic hydrothermal fluids (dominant zone 1), an...
Abstract— The known encounter velocity (6.1 kms −1 ) and particle incidence angle (perpendicular) between the Stardust spacecraft dust emanating from nucleus of comet Wild‐2 fall within a range that allows simulation in laboratory light‐gas gun (LGG) experiments designed to validate analytical methods for interpretation impacts on aluminum foil components collector. Buckshot wide size, shape, density mineral, glass, polymer, metal grains, have been fired impact perpendicularly samples Al...
Research Article| October 23, 2018 Alkali-F-Rich Albite Zones in Evolved NYF Pegmatites: The Product of Melt–melt Immiscibility Axel Müller; Müller § Natural History Museum, P.O. 1172 Blindern, N-0318 Oslo, NorwayNatural Museum London, Cromwell Road, London SW7 5BD, United Kingdom Corresponding author e-mail address: a.b.mueller@nhm.uio.no Search for other works by this on: GSW Google Scholar John Spratt; Spratt Rainer Thomas; Thomas Helmholtz Centre Potsdam, German Geoscience GFZ,...
Exposure of the Hubble Space Telescope to space in low Earth orbit resulted numerous hypervelocity impacts by cosmic dust (micrometeoroids) and anthropogenic particles (orbital debris) on solar arrays radiator shield Wide Field Planetary Camera 2, both subsequently returned Earth. Solar cells preserve residues from smaller (and orbital but give less reliable information larger particles. Here, we present images analyses electron, ion X-ray fluorescence microscopes for impact features...
Abstract Cerianite-(Ce), ideally CeO 2 , occurs as rounded grains up to 5 μm across in a block of highly altered calcite carbonatite lava from the Kerimasi volcano, and euhedral crystals 200 carbonatite-derived eluvial deposits Kisete Loluni explosion craters Gregory Rift, northern Tanzania. X-ray powder diffraction data (a = 5.434(5) Å) Raman spectroscopy (minor vibration modes at 184 571 cm —1 addition strong signal 449 ) suggest presence essential amounts large cations oxygen vacancies...