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Terrestrial Perspective On The Formation, Evolution, And Detection Of Zeolites In Lacustrine Environments On Early Mars, Gayantha Roshana Loku Kodikara
Terrestrial Perspective On The Formation, Evolution, And Detection Of Zeolites In Lacustrine Environments On Early Mars, Gayantha Roshana Loku Kodikara
Theses and Dissertations
This study evaluates the possible formation and evolution mechanisms of zeolites on early Mars with possible explanations for their limited detections using Earth analogs. This study focuses on the formation of zeolites in the closed basin lakes where the largest relatively pure concentrations of natural zeolites are found on Earth. Five working hypotheses were formulated to explore the limited detection of zeolites in closed basin lakes on Mars and different styles of scientific reasoning with suitable examples were used to test the independent, converging lines of inquiry. Zeolites may not be identifiable in certain locations on Mars using orbital data …
Analyzing Weathering Patterns In Modern And Paleolake Deposits Of Tecopa, California: Implications For The Detection Of Paleolakes On Mars, Jason Benjamin Carman
Analyzing Weathering Patterns In Modern And Paleolake Deposits Of Tecopa, California: Implications For The Detection Of Paleolakes On Mars, Jason Benjamin Carman
Theses and Dissertations
This study focuses on two stratigraphic sections from the Tecopa paleolake and samples from the modern Tecopa and Amargosa River basins as a terrestrial analogue to Martian paleolakes. Previous work shows that the later stages of Pleistocene Lake Tecopa were highly alkaline and saline due to evaporation, which led to the formation of authigenic lacustrine minerals such as zeolites, clays, and precipitates that are potentially similar to Martian paleolakes. Paleolakes can provide information on past aqueous processes, such as the changes in the hydrologic cycle that a particular area experienced over the lifespan of a lake on Earth or Mars. …
Surface Alteration In The Ölkelduháls, Nesjavellir, And Geysir Hydrothermal Systems, Iceland: Implications For Mars, Jordan Ludyan
Surface Alteration In The Ölkelduháls, Nesjavellir, And Geysir Hydrothermal Systems, Iceland: Implications For Mars, Jordan Ludyan
Theses and Dissertations
Silica- and sulfate-rich deposits observed by Mars Exploration Rover (MER) Spirit near Home Plate, Gusev crater, Mars, indicate alteration of Mars basalt by a diverse array of hydrothermal fluids and processes. Constraining the precise fluid conditions present at the time of deposition for these deposits on Mars relies on investigations of terrestrial hydrothermal systems that produce similar mineral assemblages. Alteration products and fluids collected from the Ölkelduháls, Nesjavellir, and Geysir hydrothermal areas in southern Iceland cover a wide range of end-member and intermediate fluid and alteration environments, and provide a means to compare the secondary minerals produced from different hydrothermal …
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 …
Sedimentology And Stratigraphy Of The Middle Jurassic Preuss Sandstonein Northern Utah And Eastern Idaho, Preston Scott Cook
Sedimentology And Stratigraphy Of The Middle Jurassic Preuss Sandstonein Northern Utah And Eastern Idaho, Preston Scott Cook
Theses and Dissertations
The purpose of this study is to analyze the sedimentology and stratigraphy of the Middle Jurassic Preuss Sandstone and re-evaluate past sedimentological interpretations. The Preuss is located in northern Utah, western Wyoming and eastern Idaho and is stratigraphically equivalent to the Entrada Sandstone, which is Callovian in age (Dossett et al., 2014). This study is the first attempt at 1) a sequence stratigraphic framework, 2) a petroleum system analysis and 3) an extraterrestrial analog study for the Preuss. This study frames the Preuss within three broad facies groups: marine, coastal and terrestrial. The marine group includes the open marine and …
Low-Shield Volcanism: A Comparison Of Volcanoes On Syria Planum, Mars And Snake River Plain, Idaho, Amanda Olivia Henderson
Low-Shield Volcanism: A Comparison Of Volcanoes On Syria Planum, Mars And Snake River Plain, Idaho, Amanda Olivia Henderson
Theses and Dissertations
Volcanoes are key indicators of a planet's internal structure, mechanics, and evolutionary history. Consequently, understanding the types and ages of volcanoes on a planet's surface is an important endeavor. In an attempt to better understand the relationship between morphometry and volcanic processes, we compared low-shield volcanoes on Syria Planum, Mars, with basaltic shields of the eastern Snake River Plain. We used 133 volcanoes on Syria Planum that are covered by Mars Orbiting Laser Altimeter (MOLA) and High Resolution Stereo Camera (HRSC) elevation data and 246 eSRP shields covered by the National Elevation Dataset (NED) for this comparison. Shields on Syria …
Hydrothermal Acid-Sulfate Alteration At Krafla And Námafjall, Ne Iceland: Implications For Gusev Crater And Meridiani Planum, Mars, George L. Carson
Hydrothermal Acid-Sulfate Alteration At Krafla And Námafjall, Ne Iceland: Implications For Gusev Crater And Meridiani Planum, Mars, George L. Carson
Theses and Dissertations
Opaline silica, sulfate, and phyllosilicate-bearing deposits have been detected on Mars from both obiters and rovers, indicating extensive aqueous alteration of the basaltic surface, some of which likely occurred under hydrothermal conditions. Ongoing hydrothermal acid-sulfate alteration of Mars-like high-Fe (15.48-16.27 wt. % Fe2O3T) basalts and hyaloclastites in northeastern Iceland was studied to help interpret the products of alteration in analogous environments on ancient Mars. The Krafla and Námafjall areas feature intense surface alteration in gas- (fumarole) and fluid- (hot spring/mud pot) dominated settings. Influx of H2S gas (H2S + 2O2 = H2SO4) produced steam-derived acid-sulfate waters with pH values 1.96-2.50 …
The Origins Of Four Paterae Of Malea Planum, Mars, Susan K. Larson
The Origins Of Four Paterae Of Malea Planum, Mars, Susan K. Larson
Theses and Dissertations
Malea Planum is a volcanic plain on the southern rim of Hellas Planitia, the largest impact basin on Mars. Four large circular structures on Malea Planum have traditionally been identified as paterae, or low relief, central vent volcanoes (Plescia and Saunders, 1979). A geologic map was constructed and new crater counts made to explore the ages and origins of the paterae. Amphitrites and Peneus Paterae have radial patterns of wrinkle ridges on their flanks and distinct summit calderas (95 km and 130 km across) with arcuate bounding scarps. In contrast, Malea and Pityusa Paterae are broad depressions with diameters greater …