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Full-Text Articles in Physical Sciences and Mathematics
The Geochemistry And Mineralogy Of Surface Hydrothermal Alteration At Nesjavellir, Sw Iceland, Chase Glenister
The Geochemistry And Mineralogy Of Surface Hydrothermal Alteration At Nesjavellir, Sw Iceland, Chase Glenister
Theses and Dissertations
Abundant sulfates have been detected by the Mars Exploration Rover Spirit in the Columbia Hills of Mars, consistent with extensive alteration of basalt by hydrothermal processes. This study uses Iceland’s Nesjavellir geothermal system as an analogue for Columbia Hills hydrothermal alteration. This terrestrial site is home to a variety of acidic and near-neutral waters that are actively altering the Mars-like basalt of host volcano Mt. Hengill. Hydrothermal features heated by H2S gas and phase-segregated steam created oxidizing acid-sulfate conditions at the surface with pH values varying between 3.0 and 2.0 and near-boiling temperatures. Mobilization of cations (FeO, MgO, CaO, Na2O, …
Hydrothermal Alteration At Devil's Kitchen In The Lassen Volcanic National Park: A Mars Analogue, Andy Wanta
Hydrothermal Alteration At Devil's Kitchen In The Lassen Volcanic National Park: A Mars Analogue, Andy Wanta
Theses and Dissertations
The Devil’s Kitchen hydrothermal site, within the Lassen Volcanic National Park, has hydrothermal features that cover a wide range of pH conditions (2-7). Analysis of mineral precipitates, hot spring mud, unaltered substrate rock, and hot spring and meteoric water reveal a wide variety of alteration minerals, geochemical conditions, and water chemistry. Mineral suites included primary igneous phases, silica phases, clay minerals, and sulfate phases. Aluminum sulfates are the dominant sulfate species present with abundant Na+, Fe3+, and Ca2+ sulfate phases and less common K+ sulfates. Amorphous silica precipitates were observed in three samples from a near-neutral hot spring and one …