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Showing 1 to 8 of 8 for “"Silicic Magma"”.
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Origin of net-veined and mixed-magma ring intrusions
Net-veined and mixed-magma ring intrusions are a characteristic simultaneous emplacement of mafic, intermediate and silicic magmas. Net-veined ring-intrusions consist of areas of granophyric net-veined mafic to intermediate rock which elsewhere forms rounded to elongate pillows in a silicic host …
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Petrogenetic Relationship of the Postcaldera Eruptions of Mount Mazama, Crater Lake, Oregon; Evolution of a Sub-volcanic Magma Chamber Following a Large Silicic Eruption
… formed a dome (Bacon et al., 2002). How magmatic systems evolve following a shallow, relatively large silicic eruption is the focus of this study. In situ geochemical analysis coupled with high-resolution textural images of plagioclase crystals in the four postcaldera volcanic edifices …
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Petrogenesis of Eocene-Oligocene magmatism of the Sulphur Springs Range, central Nevada: The role of magma mixing
… volcanic rocks in the range exhibit evidence of magma mixing and invite comparisons with other mineralized, Eocene mixed magma systems like the Bingham porphyry Cu deposit 300 km farther to the east. The Sulphur Springs igneous suite ranges compositionally through rhyolite, dacite, andesite and …
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Crystallisation history of rhyolite magmas at Tarawera volcano, New Zealand, from in-situ 238U-230Th disequilibrium dating and trace element geochemistry of zircon
… of the episodes involved at least two distinct magma types that were erupted from the same conduit. New SIMS 238U-230Th disequilibrium dating and trace element analyses (U, Th, Y, Hf, Ce, Ti) of individual zircon crystals provide insight to the timescales of silicic magma system processes. …
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The petrology and geochemistry of Precaldera Magmas, Long Valley Caldera, Eastern California
… from a heterogeneous, interactive, deep crustal magmatic -system. The suite consists of ( 1) widespread, predominately porphyritic olivine-augite basalt / trachybasalt / trachyandesite flow sequences (> 24 km³), (2) local orthopyroxene -phyric silicic trachyandesite flows (> I km³), and (3) …
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Deciphering the 4-D geological framework of the Taupo-Reporoa Basin: Implications for hydrothermal fluid flow and volcanism
… extraordinary heat output indicate that it is magmatically active. Yet the tectonic, volcanic, and magmatic processes that influence TRB evolution, and its tectonic context relative to the North Island, are poorly understood. The first part of this thesis (chapters 2 and 3) outlines the …
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Petrologic, geochemical and isotopic evolution of rhyolite lavas from the Okataina, Rotorua and Kapenga Volcanic Centres, Taupo Volcanic Zone, New Zealand
… Volcanic Centre (OVC) is a highly active modern silicic magmatic system at the northeastern end of the central Taupo Volcanic Zone, North Island, New Zealand. This study presents a set of petrographic, mineralogical, geochemical and isotopic data that focuses on the rhyolite lavas erupted from …
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How similar are silicic volcanic and plutonic systems? New insights into upper crustal storage conditions and formation processes of ignimbrites
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2025-05-01