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Showing 1 to 8 of 8 for “"basaltic glass"”.
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Planetary Materials Science and Astrobiology
… mechanisms of microbial ichnofossils in basaltic glass. These studies all concern the emergence and development of terrestrial planets and habitable environments within them, and the preservation of records of biological activity through deep geologic time. This work therefore represents, …
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Carbon systematics of the Icelandic crust and mantle
… from crys- tallisation experiments conducted on basaltic glass from the Miðfell eruption, Iceland. The experiments provide new data that has been used to test a variety of barometers and crystalli- sation models used by igneous petrologists, and could aid future barometer recalibration. A key …
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Deep Earth volatile cycles as revealed by basalt chemistry
… Volatile- trace element systematics in suites of basaltic glass and melt inclusions have been widely used to infer volatile abundances in the depleted mantle, but have resulted in a large diversity of estimates. In this thesis a new statistical treatment of such datasets is developed, using simple …
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Paleomagnetism of Lonar impact glass
Several dozen impact glasses from Lonar Crater, in Maharashtra, India, were analyzed for evidence of impact-generated paleofields, and possible motional remanent magnetization. Lonar Crater formed when a meteorite impacted a bed of Deccan Trap basalts. Upon impact, the basalt was super heated into …
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Microstructural evolution of silicate immiscible liquids in solidifying ferrobasalts
… and Fe-rich droplets dispersed in the Si-rich glassy mesostasis of rapidly cooled rocks. Crucially, the different physical properties of these unmixed liquids mean that they may migrate and separate within a granular medium, forming chemically distinct accumulations. I combine experiments, …
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Helium isotope geochemistry of oceanic volcanic rocks : implications for mantle heterogeneity and degassing
… partitioning in mid-ocean ridge basalt (MORB) glass, performed by crushing and melting in vacuo, show that a significant fraction of the helium resides within vesicles. Measured concentrations are therefore a function of original helium content, magmatic history, vesicle size and quantity, and …
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The high temperature geochemistry of vanadium: From isotope ratios in ocean island basalt to thermal diffusion processes at the core-mantle boundary
… gradient piston cylinder experiments using basaltic melt to probe the melt structure and oxygen fugacity variations during thermal diffusion. Thermal diffusion is a mass diffusion process driven by a temperature gradient which can generate substantial isotopic fractionation in silicate …
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Investigating Microbial Trace-fossils and Abiotic Alteration in Hydrovolcanic Tuffs of the Fort Rock Volcanic Field, Oregon
… mineralogy, and geochemistry of two continental basaltic hydrovolcanic deposits - Reed Rocks and Black Hills - in the Fort Rock Volcanic Field (FRVF) are investigated. Methods include petrographic microscopy, micro and powder X-ray diffraction, SEM/BSE/EDF imaging, energy dispersive spectroscopy, …