Results 121 to 130 of about 22,288 (246)

Petrogenesis and Tectonic Implication of the Newly Identified Rhyacian and Orosirian Orthogneisses in the Northwestern Part of the Gyeonggi Massif (Soyeonpyeongdo and Ganghwado Areas), South Korea: Constrained From Whole‐Rock Geochemistry and Zircon U‐Pb‐Hf Isotopic Compositions

open access: yesGeochemistry, Geophysics, Geosystems, Volume 27, Issue 9, September 2026.
Abstract The Gyeonggi Massif is one of the major Precambrian basements in the Korean Peninsula where Paleoproterozoic orthogneiss and paragneiss were widely exposed. In this study, newly identified Rhyacian to Orosirian meta‐igneous rocks from the northwestern Gyeonggi Massif (Soyeonpyeongdo and Ganghwado areas) were investigated to elucidate their ...
Seung Hwan Lee   +5 more
wiley   +1 more source

Factors Influencing Biotite Weathering

open access: yes, 2000
Weathering of biotite supplies nutrients such as K+ and weathers into vermiculite/montmorillonite or kaolinite, which have varying influences on soil properties and characteristics.
Reed, Ryan R.
core  

The Distinction Between Sn‐Mineralized and Sn‐Barren Granites in Sn Isotopes

open access: yesGeochemistry, Geophysics, Geosystems, Volume 27, Issue 9, September 2026.
Abstract Tin mineralization is commonly associated with highly evolved granites. However, not all highly evolved granitic rocks are mineralized with Sn. Comparative studies of Sn‐fertile and Sn‐barren granites can deepen our understanding of the key processes that lead to Sn enrichment in magmatic‐hydrothermal systems.
Cheng Xu   +5 more
wiley   +1 more source

Analysis of equilibrium in garnet-biotite-sillimanite gneisses from quebec

open access: yes, 1964
An analysis is presented of equilibrium in six specimens of garnet-biotite-sillimanite-plagioclase-potash feldspar-quartz ... gneiss from a metamorphic terrain in south-western Quebec.A nearly uniform Ti content of biotite may be accounted for by an ...
Kretz R.
core   +1 more source

Near-Infrared Spectroscopic Study of Biotite–Phlogopite (Mg# = 30~99): OH-Stretching Modes and Mg# Content Prediction Equation

open access: yesCrystals
Biotite–phlogopite minerals are a complete Mg–Fe isomorphism series of phyllosilicates. A Fourier transform infrared spectroscopy (FTIR) and electron microprobe analysis (EMPA) were conducted on end-member phlogopite, Mg–biotite, and annite samples.
Zhentao Yang   +4 more
doaj   +1 more source

Past the First Date: Ensemble Concordant–Discordant Comparison for Zircon Pb‐Loss Analysis

open access: yesGeochemistry, Geophysics, Geosystems, Volume 27, Issue 9, September 2026.
Abstract Zircon uranium–lead (U–Pb) geochronology is a cornerstone of Earth science for resolving the timing of deep‐time processes, yet the U–Pb system does not always behave as a closed chronometer. Selective loss of radiogenic Pb during fluid alteration or thermal disturbance can shift isotopic ages and generate discordant analyses. Some zircon data
Lucy M. Mathieson   +1 more
wiley   +1 more source

BIOTITE GRANITE

open access: yes
Rock Type: Igneous Rock - Granite Province: Main Range Province Age: Late Triassic (230 - 200 million years ago) Origin: Tampin, Negeri Sembilan * These featured rock is called biotite granite originated from Tampin, Negeri Sembilan, was formed in ...
Jamaludin, Siti Nur Fathiyah   +1 more
core  

Building the Andean Crust at ∼35°S: Arc Geochemistry Reveals Cretaceous Thinning and Rapid Neogene Thickening

open access: yesJournal of Geophysical Research: Solid Earth, Volume 131, Issue 9, September 2026.
Abstract Quantification of the timing and mechanisms of crustal thickening in Cordilleran orogenic hinterlands remains challenging. We address this in the Andes using whole‐rock geochemistry and zircon petrochronology from a >70 Myr volcanic record in the Tinguiririca valley of Chile (∼35° ${}^{\circ}$S), which captures a pivotal transition from ...
Chance B. Ronemus   +8 more
wiley   +1 more source

The Effects of Germanium Biotite Supplement as a Prophylactic Agent against Respiratory Infection in Calves [PDF]

open access: yesPakistan Veterinary Journal, 2012
Germanium biotite, a natural mineral, is comprised of mainly silicate. This mineral showed activities of increase in feed efficiency and non-specific immunostimulation in previous studies.
Myunghwan Jung1, Bock-Gie Jung2, Seung Bin Cha1, Min-Kyoung Shin1, Won-Jung Lee1, Seung Won Shin1, Jin-A Lee2, Yeon-Kwon Jung3, Bong-Joo Lee2 and Han Sang Yoo1*
doaj  

Porous and Permeable Crystalline Basement: Evidence for Large‐Scale Hydraulic Connectivity at Kivetty, Finland

open access: yesJournal of Geophysical Research: Solid Earth, Volume 131, Issue 9, September 2026.
Abstract Porosity and permeability in crystalline shield basement are commonly assumed to be low, yet some fault zones sustain fluid circulation over kilometer scales. Here we quantify multiscale fault‐zone connectivity at Kivetty, central Finland, by integrating legacy deep‐borehole data, including packer tests, downhole logs, and a long‐term multi ...
Daniel Carbajal‐Martínez   +8 more
wiley   +1 more source

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