Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 15 of 15 for “"Ion Microprobe"”.
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An ion microprobe study of trace element partitioning between clinopyroxene and liquid in the diopside (CaMgSi2O6) - albite (NaAlSi3O8) - anorthite (CaAl2Si2O8) system
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1981.
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Analysis of stable sulfur isotopes and trace cobalt on sulfides from the TAG hydrothermal mound
… and 2/3 basaltic sulfur (~0%). Co concentrations in pyrite analyzed by ion microprobe primarily reflect depositional temperatures. The δ34S and Co data are combined to provide information regarding the sources and temperatures of parent fluids, the genetic relationships among sample types, …
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A study of the physical adsorption of nitrogen gas on polished 347 stainless steel at very low pressures
This investigation involves the study of the physical adsorption of nitrogen gas on a polished 347 stainless steel surface in the 1 x 10⁻⁹ to 1 x 10⁻⁷ torr pressure region. Characterization studies on the polished 347 stainless steel surface were also conducted utilizing a scanning electron …
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The crystal chemistry of titanite
The chemical substitutions of primary importance in natural titanites are (Al,Fe)<sup>3+</sup> + (F,OH)<sup>-</sup> ⇆ T<sub>1</sub><sup>4+</sup> + O<sup>2-</sup> , where total Al + Fe is not greater than 30 mol % and Al is usually predominant. Electron microprobe analyses and bond strength …
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Oxygen stable isotopic analysis of calcite by Raman microprobe spectrometry
The oxygen stable isotopic compositions of minerals give valuable insight into the processes that govern many low- and high-temperature geologic systems. Much research has focused on the ability to analyze the fine-scale oxygen isotopic zonation in many minerals using techniques such as the laser …
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Syn-eruptive degassing of a single submarine lava flow : constraints on MORB CO2 variability, vesiculation, and eruption dynamics
… (MORBs) exhibit a wide range of CO2 concentrations, reflecting saturation to supersaturation (and rarely undersaturation) relative to their emplacement depths. In this study, we explore the mechanisms of CO2 degassing and the implications this has for estimating the advance rates and durations …
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Syn-eruptive degassing of a single submarine lava flow : constraints on MORB CO₂ variability, vesiculation, and eruption dynamics
… (MORBs) exhibit a wide range of CO2 concentrations, reflecting saturation to supersaturation (and rarely undersaturation) relative to their emplacement depths. In this study, we explore the mechanisms of CO2 degassing and the implications this has for estimating the advance rates and durations …
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Establishing a Baseline for Kinetic and Thermodynamic Origins of Vital Effects: Toward an Understanding of Factors Controlling Mg Signatures in Calcite
… and seawater chemistry begin by assuming compositional signatures reflect environmental conditions of formation. The Mg/Ca ratio in marine cements and calcified skeletal structures is a widely used proxy for reconstructing past earth environments. Many studies have positively correlated Mg content …
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Development of proxy seawater records from gorgonian coral skeletons
Information about the history of Earth’s climate system is largely derived from the chemical composition of biogenic skeletons preserved in the geologic record. The isotope and elemental composition of scleractinian corals have proven to be useful tools for palaeoceanographic reconstruction, …
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Investigation of the monazite chemical dating technique
In order to evaluate the electron microprobe (EMP) method for chemical dating of monazite, we chemically analyzed selected suites of monazite grains that were previously dated by standard U/Pb isotopic methods at three laboratories each equipped with a sensitive high resolution ion microprobe …
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Rhodoliths as environmental archives in the tropics
… coralline red algae studies show that the variations of specific trace elements along these growth bands can reflect secular changes in various environmental parameters. This study aims at assessing and further extending the ability of rhodolith-forms of coralline red algae to reconstruct …
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Rhodoliths as environmental archives in the tropics
… coralline red algae studies show that the variations of specific trace elements along these growth bands can reflect secular changes in various environmental parameters. This study aims at assessing and further extending the ability of rhodolith-forms of coralline red algae to reconstruct …
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Eo-Variscan Orogenesis in the Guilleries Massif, Catalan Coastal Ranges, Northeastern Spain Recorded by U-Th-Pb ages of Monazite Inclusions in Metamorphic Garnet
… Spain which preserve multiple rounds of deformation and metamorphism. The massif records a classic Variscan low-pressure and high-temperature metamorphic field gradient and represents part of the metamorphic core of the Variscan Orogeny. The lack of overprinting from the younger Alpine Orogeny …