Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1972. / Bibliography: leaves 131-138. / 185 l illus., tables

Thesis (M. Phil.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 102-107).

abstract: With the InSight mission deploying a seismometer , Martian bulk chemical compositional models are more important than ever. Three largely consistent models for the Martian mantle have been suggested over the past two decades. Of these three, two are fairly similar and one is dramatically different. Of these three, the EH70 (Sanloup et al., 1999) models have the systematically lower divalent cation to silicon ratios as compared to the other model, the DW85 (Dreibus and Wanke, 1985) model. However, impact of such a low (Mg+Fe+Ca)/Si ratio on mineralogy has not been experimentally investigated. Measurements have been made of the mineralogy of the EH70 bulk mantle composition (Sanloup et al., 1999)) through in-situ laser-heated diamond anvil cell (LHDAC) and large volume press (LVP). Majorite-garnet (Mj) dominated mineralogy has been observed up to 25 GPa. Bridgmanite (Bm) begins to appear from 25.2 GPa and continues in a mixed phase with Mj up to 27 GPa at which point only Bm and calcium perovskite (CaPv) remain. Akimotoite (Ak) is stable up to 1873 K, higher by ≈300 K compared to numerical calculations (Connolly, 2009). This may result in an Ak layer in the Martian mantle, something missing in Earth’s mantle. The overall ratio of pyroxene to olivine polymorphs by volume is high, approaching pure pyroxene. This agrees with numerical calculations. Additionally, ferropericlase (Fp) is stable at lower temperatures, suggesting a higher dependence on temperature for its stability, something that is different from Perple_X calculations which show a strong dependence on pressure. Furthermore, Mj, which make up a majority of the volume of EH70 mantles, was measured to increase in Fe content as pressure increases. The more oxidizing conditions coupled with the silicon-rich composition resulted in three times higher Fe3+ content in Mj as opposed to a pyrolite model. This increased Fe3+ meant our Mj composition approached that of skiagite (Ski,Fe2+ 3 Fe3+ 2 Si3O12) and this caused Mj to have a very low compressibility of only 152.8 GPa, lower than any other Mj compositions in literature. This result suggests that a mantle with EH70 bulk composition would have lower than predicted seismic wave velocities , lower than Perple_X predicts. The Al content of Mj was also found to suppress the first derivative of compressibility to 4.45, lower than that of Ski100 at 6.7. Such differences compared with pyrolitic composition are important to estimate the velocity profiles and to model the dynamics of the Martian mantle. This dataset of mineralogy and composition can also model terrestrial exoplanetary mantles. Current measurements of stellar abundances show a wide range of compositions, and especially compositions with (Mg+Fe+Ca)/Si ratios approaching 1 (Brewer and Fischer, 2016). This experimental study of EH70 composition can fill-in this gap. / Dissertation/Thesis / Masters Thesis Natural Science 2019

Digitized by Kansas State University Libraries

Call number: LD2668 .T4 1939 G55 / Master of Science

Call number: LD2668 .T4 1949 J54 / Master of Science

Call number: LD2668 .T4 1949 M22 / Master of Science

<p> Compositional analysis of reservoir rock is a vital aspect of oil exploration and production activities. In a broad sense, knowing the mineral composition of a reservoir can help with characterization and interpretation of depositional environments. On a smaller scale, identifying mineralogy helps calibrate well logs, identify formations, design drilling and completion programs, and screen for intervals with potential problem minerals, such as swelling clays. The petroleum industry utilizes two main methods to find compositional mineralogy, x-ray diffraction (XRD) and thin section analysis. Both methods are time consuming, expensive, and destructive. An alternative method for compositional analysis that includes quantitative mineralogy is a valuable prospect, especially if it had the potential to characterize the total organic content (TOC). </p><p> The remote sensing community has been using infrared spectroscopy to analyze mineralogy for years. Within the last ten years, the advancement of infrared spectrometers and processing programs have allowed infrared spectra to be taken and analyzed faster and easier than before. The objective of this study is to apply techniques used in remote sensing for quantitatively finding mineralogy to the petroleum industry. While developing a new methodology to compositionally analyze reservoir rock, a database of infrared spectra of relevant minerals has been compiled. This database was used to unmix spectra using a constrained linear least-squares algorithm that is used in the remote sensing community. A core has been scanned using a hand-held infrared spectrometer. Results of the best method show RMS error from mineral abundance to be under five percent.</p>

No description available.

Copperstone is a mid-Tertiary "detachment gold" deposit that is herein classified as a new subtype of epithermal deposit. Copperstone is similar to many active geothermal systems in terms of host lithology, temperature, and related siliceous alteration mineralogy, except in the hypogene oxide assemblages, the high salinity, and the lack of sulfides and the pathfinder toxic elements. The host rock is mainly Jurassic quartz latite porphyry and Tertiary sedimentary breccias. Early stages of alteration were K-metasomatic and propylitic, and alteration that accompanied gold mineralization was mainly chloritization and silicification. Mineralization is structurally controlled and is restricted along the Copperstone Listric Fault with minor mineralization along high-angle NE and NW faults, as with many other deposits in west-central Arizona. The gold stage of mineralization was superimposed on previously K-metasomatized rocks. Hypogene mineralization can be divided into 3 paragenetic stages: early amethyst-quartz-Fe-rich-chlorite-specularite-hematite-Au° of stage C; late-stage fine-grained euhedral quartz-adularia-chrysocolla ± malachite ± magnetite ± chalcopyrite-pink fluorite-barite-ankerite-calcite-Au° of stage D; and barren quartz-pale green fluorite-barite-calcite-hematite of stage E. Gold occurs as free particles or is encapsulated in amethyst and late fine-grained euhedral quartz. The time of mineralization is Miocene or younger and the depth of mineralization was 1 Km. Gold mineralization was related to boiling such that a hot spring system did operate at Copperstone. Copperstone is a hydrothermal system created during the last stages of detachment faulting, with mineralization controlled by boiling, and "second boiling" was the principal trigger of Copperstone gold deposition in an environment of falling temperatures and pressures on chloride-rich brine fluids. Variation in δ³⁴S indicates that two different fluids are involved in this system, and that a deeper, "lighter" hydrothermal fluid mixed with a "heavier" basin brine. δ¹⁸O values from carbonates confirm the extent of isotopic exchange with an aqueous reservoir and indicates that oxidation accompanied gold deposition.