Mentor 1
Lindsay McHenry
Location
Union Wisconsin Room
Start Date
28-4-2017 1:30 PM
End Date
28-4-2017 4:00 PM
Description
Hydrothermal sites explored at Lassen Volcano, California reveal alteration processes ranging from acid-sulfate to more neutral conditions that can be either oxidizing or reducing. Often, these different environments arise near each other and are therefore closely linked. In this report, X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) analysis of minerals combined with water data collected in-situ will be interpreted to reveal alteration pathways as dacitic to andesitic host rocks come into contact with these hydrothermal conditions. Fumaroles at Pilot's Pinnacle and Terminal Geyser eject plumes of volatiles that yield acidic condensates, leading to leaching of most soluble ions and, in some cases, S precipitation. Pilot's Pinnacle also hosts a cool, near-neutral stream actively precipitating minerals. Together these observations allow us to understand fine-scale behavior in a complex alteration system.
Acid-sulfate and near-neutral hydrothermal environments have beeninvoked to explain certain geological features on Mars such as silica enrichment and sulfate minerals inrocks and soils. These environments have been observed by Mars Exploration Rover (MER) Spirit atHome Plate, Gusev crater. Furthermore, evidence of more evolved (dacitic/andesitic) volcanism has also been provided by Mars Science Lab (MSL) Curiosity. On Earth, hydrothermal environments sustain diverse microbial ecosystems. Better understanding chemical behavior in terrestrial systems can allow us to apply more refined interpretations to observations gathered in the search for biosignatures on Mars, and help to identify noteworthy samples for collection in future missions to Mars.
Assessing Hydrothermal Conditions At Lassen Volcano With Implications For Early Mars
Union Wisconsin Room
Hydrothermal sites explored at Lassen Volcano, California reveal alteration processes ranging from acid-sulfate to more neutral conditions that can be either oxidizing or reducing. Often, these different environments arise near each other and are therefore closely linked. In this report, X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) analysis of minerals combined with water data collected in-situ will be interpreted to reveal alteration pathways as dacitic to andesitic host rocks come into contact with these hydrothermal conditions. Fumaroles at Pilot's Pinnacle and Terminal Geyser eject plumes of volatiles that yield acidic condensates, leading to leaching of most soluble ions and, in some cases, S precipitation. Pilot's Pinnacle also hosts a cool, near-neutral stream actively precipitating minerals. Together these observations allow us to understand fine-scale behavior in a complex alteration system.
Acid-sulfate and near-neutral hydrothermal environments have beeninvoked to explain certain geological features on Mars such as silica enrichment and sulfate minerals inrocks and soils. These environments have been observed by Mars Exploration Rover (MER) Spirit atHome Plate, Gusev crater. Furthermore, evidence of more evolved (dacitic/andesitic) volcanism has also been provided by Mars Science Lab (MSL) Curiosity. On Earth, hydrothermal environments sustain diverse microbial ecosystems. Better understanding chemical behavior in terrestrial systems can allow us to apply more refined interpretations to observations gathered in the search for biosignatures on Mars, and help to identify noteworthy samples for collection in future missions to Mars.
