A5112700853- Geological and Geochemical Analysis
- Mineralogy and Gemology Studies
- Geochemistry and Geologic Mapping
- earthquake and tectonic studies
- Geology and Paleoclimatology Research
- Crystal Structures and Properties
- Clay minerals and soil interactions
- High-pressure geophysics and materials
- Hydrocarbon exploration and reservoir analysis
- X-ray Diffraction in Crystallography
- Geochemistry and Elemental Analysis
- Astro and Planetary Science
- Crystallization and Solubility Studies
- Glass properties and applications
- Geological Studies and Exploration
- Paleontology and Stratigraphy of Fossils
- Material Dynamics and Properties
- Geological formations and processes
- Cultural Heritage Materials Analysis
- Laser-induced spectroscopy and plasma
- Planetary Science and Exploration
- Marine and environmental studies
- CO2 Sequestration and Geologic Interactions
- Isotope Analysis in Ecology
- Geotourism and Geoheritage Conservation
Louisiana State University
2013-2023
Barry University
2019
Lunar and Planetary Institute
1983-1985
Johnson Space Center
1983
Arizona State University
1980-1982
The Ti content of biotite can serve as a geothermometer for graphitic, peraluminous metapelites that contain ilmenite or rutile and have equilibrated at roughly 4-6 kbar. relationship between Ti- coutent, temperature, Mg/(Mg + Fe) value was calibrated empirically using an extensive natural data set (529 samples) from western Maine south-central Massachusetts in combination with the petrogenetic grid Spear et al. (1999). calculated Ti-saturation surface is curved such given value,...
A nomenclature for tourmaline-supergroup minerals is based on chemical systematics using the generalized tourmaline structural formula: XY3Z6(T6O18)(BO3)3V3W, where most common ions (or vacancy) at each site are X = Na1+, Ca2+, K1+, and vacancy; Y Fe2+, Mg2+, Mn2+, Al3+, Li1+, Fe3+, Cr3+; Z T Si4+, B3+; B V OH1- O2-; W OH1-, F1-, O2-. Most compositional variability occurs X, Y, Z, W, sites. Tourmaline species defined in accordance with dominant-valency rule such that a relevant dominant ion...
Tourmaline-supergroup minerals are ubiquitous accessory in rocks of the Earth’s crust. They can adjust their composition to suit a wide variety environments, and therefore display remarkable range stability terms pressure, temperature, fluid composition, host-rock composition. Because this compositional sensitivity, tourmaline is an excellent indicator environmental conditions its host. This further enhanced by negligible diffusion up high temperatures strongly refractory character during...
Research Article| October 01, 2011 Tourmaline: A Geologic DVD Barbara L. Dutrow; Dutrow 1Department of Geology and Geophysics, Louisiana State University Baton Rouge, LA 70803 USA E-mail: dutrow@lsu.edu; glhenr@lsu.edu Search for other works by this author on: GSW Google Scholar Darrell J. Henry Author Article Information Publisher: Mineralogical Society America First Online: 09 Mar 2017 Online ISSN: 1811-5217 Print 1811-5209 © the Elements (2011) 7 (5): 301–306....
Research Article| October 01, 2011 Tourmaline as a Petrologic Forensic Mineral: A Unique Recorder of Its Geologic Past Vincent J. van Hinsberg; Hinsberg 1Department Earth Sciences, University Oxford South Parks Road, Oxford, UK E-mail: V.J.vanHinsberg@gmx.net Search for other works by this author on: GSW Google Scholar Darrell Henry; Henry 2Department Geology and Geophysics, Louisiana State University, Baton Rouge, LA 70803, USA Barbara L. Dutrow Author Article Information Publisher:...
An extensive natural biotite data set from western Maine constrains the temperature and crystalchemical controls on saturation Ti levels in biotites metapelites. The geologically petrologically well-characterized metamorphic terrain associated with M3 metamorphism of Acadian Orogeny is ideal for this approach that occurred at roughly isobaric conditions 3.3 kbar, chemical equilibrium was closely approached. these metapelites exhibits systematic variations contents over a continuum grades...
The manner in which F is incorporated into the tourmaline structure depends on internal influences such as crystallographic constraints and external temperature, pressure, local mineral assemblage fluid composition. Tourmaline has a general formula XY 3 Z 6 ( T O 18 )(BO ) V W , with most common site-occupancies being: X = Ca 2+ Na 1+ K □ (vacancy); Y Li Mg Fe Mn Al 3+ Cr ; Si 4+ B ≡ [O(3)] OH 1− 2− [O(1)] . Of particular importance for understanding incorporation that occurs solely at O(1)...
Tourmaline studies have been an integral part of science and scientific exploration for centuries continue to flourish today.In the 19 th century, curious pyroelectric piezoelectric properties this mineral attracted attention scientists who considered tourmaline central a grand unification theories heat, electricity magnetism.The common occurrence in granites granitic pegmatites was widely known at that time, but, subsequently, discovered great range igneous, metamorphic sedimentary rocks...
Silver-gray tourmaline fibers intergrown with a deep pink elbaite host from the Cruzeiro mine, Minas Gerais, Brazil, provide evidence for compositional evolution of magmatic and hydrothermal fluids involved in pegmatite formation. Optical back-scattered electron imaging, together detailed microanalysis, establish that fibers, 0.05‐0.3 mm width, are com plexly zoned developed four distinct generations marked by discrete compositions replacement textures. Fiber growth is punctuated periods...
Tourmaline grains extracted from rocks within three ultrahigh-pressure (UHP) metamorphic localities have been subjected to a structurally and chemically detailed analysis test for any systematic behavior related temperature pressure. Dravite Parigi, Dora Maira, Western Alps (peak P-T conditions ~3.7 GPa, 750 °C), has structural formula of X(Na0.90Ca0.05K0.01⃞0.04) Y(Mg1.78Al0.99Fe2+0.12Ti4+0.03⃞0.08)Z(Al5.10Mg0.90)(BO3)3TSi6.00O18V(OH)3W[(OH)0.72F0.28]. Lago di Cignana, Alps, Italy (~2.7-2.9...
Tourmaline uniquely records evidence of its geologic history in composition and, if properly decoded, provides insight into the environment formation.Recent studies suggest that tourmaline not only retains chemical information on host-rock environment, but also signatures fluid phase with which it interacted.Such are embedded major-and minor-element compositions as well isotopes.Some these elemental qualitative, while others provide quantitative evaluation evolving fluid-phase...
Fe2+- and Mn2+-rich tourmalines were used to test whether Fe2+ Mn2+ substitute on the Z site of tourmaline a detectable degree. Fe-rich from pegmatite Lower Austria was characterized by crystal-structure refinement, chemical analyses, Mössbauer optical spectroscopy. The sample has large amounts (~2.3 apfu), substantial Fe3+ (~1.0 apfu). On basis collected data, structural refinement spectroscopic an initial formula determined assigning entire amount (no delocalized electrons) Ti4+ electrons...
Abstract Tourmaline supergroup minerals with fibrous morphology record and respond to changing conditions in fluid-rich hydrothermal environments. Based on published data, hand-specimen optical observations, new chemical analyses of tourmalines from localities worldwide, several commonalities are apparent. Fibers typically nucleate a preexisting substrate tourmaline, but the fibers generally have dramatically different composition than tourmaline. When single tourmaline crystal, growth is...
Maruyamaite, ideally K(MgAl2)(Al5Mg)Si6O18(BO3)3(OH)3O, was recently approved as the first K-dominant mineral-species of tourmaline supergroup. It occurs in ultrahigh-pressure quartzofeldspathic gneisses Kumdy-Kol area Kokchetav Massif, northern Kazakhstan. Maruyamaite contains inclusions microdiamonds, and probably crystallized near peak pressure conditions UHP metamorphism stability field diamond. Crystals occur anhedral to euhedral grains up 2 mm across, embedded a matrix quartz...
The mineralogical
Major and trace element, U-Pb zircon geochronology Pb-isotopic data are presented on plutons from the San Nicolás batholith of central southern Peru. The major oxides 9 samples indicate a high-K calc-alkaline trend, element discriminant diagrams reveal affinities to volcanic arc or late- post-collision intrusions. apparent contradiction implied by Rb-Hf-Ta triangular diagram (within-plate) strongly suggests loss Rb, an interpretation supported extensive deuteric alteration sericitization...