"What is the definition of life? Is it likely that there is life on other planets?"
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Chemistry and biology of ultramafic-hosted alkaline springs
Project Investigators: Michael Mottl
Other Project Members
Thomas McCollom (Collaborator)Summary
Ultramafic rock makes up Earth’s mantle and is an abundant material in the inner solar system. When water is added it converts to serpentinite, producing in the process H2 and, when CO2 is present, methane, both of which are ideal fuels for microbial activity. We are studying serpentinite mud volcanoes in the Mariana forearc, where water ascends from the subducting Pacific plate into the overlying mantle, producing large volumes of serpentinite that exhibits unusual fluid chemistry (e.g., pH 12.6) and extremophilic microbial activity, as an analog to extraterrestrial environments such as on Mars and the asteroids.
Astrobiology Roadmap Objectives:
- Objective 5.3: Biochemical adaptation to extreme environments
- Objective 7.2: Biosignatures to be sought in nearby planetary systems
Project Progress
We have determined that these methane-rich waters, which are the highest pH waters ever found on Earth, support abundant Archaea that anaerobically oxidize methane (AOM) to carbonate while reducing sulfate, all at an in-situ pH of 13.1. Such a high pH cannot be generated by serpentinization alone. In collaboration with Dr. Tom McCollom of the Unversity of Colorado NAI, and with additional funding from NSF, we are modeling the processes that generate this extreme environment, including 1) dehydration and dissolution of subducted organic and inorganic carbon from the subducting oceanic plate with increasing temperature and pressure; 2) ascent of this water and dissolved carbon and its input into the ultramafic rock of the overriding plate; 3) serpentinization of this rock and accompanying generation of H2; 4) reaction of H2 with carbon to make methane that ultimately fuels extremophilic (high pH) microbial communities in the shallow subseafloor. This methane is abiogenic, so this process may be analogous to what may be happening on Mars.
Mission Involvement
Mars Reconaissance OrbiterInvestigates possible source of abiogenic methaneMars ExpressInvestigates possible source of abiogenic methaneMars Science LabInvestigates possible source of abiogenic methaneField Expeditions
NameSampling Mariana Forearc Serpentinite Mud VolcanoesDatesMarch 22, 2003 - May 4, 2003Location14N 146EDescriptionWe cored ten serpentinite mud volcanoes in the Mariana forearc, recovering serpentinite, included pore water, and microbes.Cross-Team Collaborations
Tom McCollom, University of Colorado NAI, with whom I have collaborative research funding from NSF to study serpentinization and microbial activity in the Mariana forearc.
Publications
Meech, K.J. & Mottl, M.J. (2008). Origin of Earth's water - current key issues. Astrobiology, 8.
Mottl, M.J., Glazer, B.T., Kaiser, R.I. & Meech, K.J. (2008). Water and Astrobiology. Chemie der Erde, 67:253-282.
- HANDBOOK OF STAR FORMING REGIONS
- A Rare low mass quadruple spectroscopic AND eclipsing binary
- A search for Main Belt Comets in Pan-STARRS 1
- A search for primordial water from deep in the Earth's mantle
- A spectroscopically unique Main Belt asteroid: 10537 (1991 RY16)
- A Supertree Analysis of the Metazoan Phylogeny
- Acquisition and Installation of a new Cameca ims 1280 ion microprobe
- Acquisition and Installation of Witec Confocal Raman microscope scanning system
- Amorphization of Crystalline Water Ice in the Solar System
- Assessing the likelihood of supernova impact of protoplanetary disks
- Carbonate Lithologies on Devon Island, Canada
- Chemistry and biology of ultramafic-hosted alkaline springs
- Chemistry of the NH3/H2O system
- DIVERSITY AND BIOGEOGRAPHY OF THE UNIQUE TROPICAL PHYLUM PLACOZOA
- Dynamical Evolution of Astroid Belt and the Parent Bodies of Iron Meteorites
- Ecology of a Hawaiian lava cave microbial mat
- FMARS Long Duration Mission: a simulation of manned Mars exploration in an analogue environment, Devon Island, Canada
- Formation and Detection of Hot-Earth Objects in Systems with Close-in Jupiters
- Formation and the Prospects of the Detection of Habitable Planets in Extreme Planetary Systems
- Formation of Molecular Hydrogen via Interaction of Ionizing Radiation with Hydrocarbon Ices in the Interstellar Medium
- Formation of Planetesimals in a Dynamically Evolving Nebula
- FU ORIONIS ERUPTIONS
- Ice Ages on Mars
- Ice at the Mars Phoenix Landing Site
- Ice on Main Belt Comets
- Icelandic subglacial lakes
- Mechanisms of Marine Microbial Community Structuring
- Mechanistical Studies on the Non-Equilibrium Chemistry of Unusual Carbon Oxide in Solar System Ices
- Modeling grain surface reaction pathways for large organic molecules
- Molecular Deuteration on grain surfaces
- NEWBORN BINARIES
- Observations and Models of comet 17P/Holmes
- Origin and Activation Mechanism of Main Belt Comets
- Origin of Irregular Satellites
- Recovery of comet 85P/Boethin for the Deep Impact Extended Mission
- Sediment-buried basement deep biosphere
- Serpentinazation and abiogenic methane in the Mariana Forearc
- Sleeping through the Arctic Martian Sol
- Spectropolarimetric studies of stars with hot jupiters
- TES study of intracrater low albedo deposits, Amazonis Planitia, Mars
- The delivery of short-lived radionucleides to the solar system
- The effect of lunar-like satellites on the orbital infrared lightcurves of Earth-analog planets
- The Main Belt distribution of basaltic asteroids
- The Size Distribution of Small KBOs
- THE VYSOS PROJECT
- Ultra-violet processing of ices in the Rosette Nebula
- Unveiling the evolution and interplay of ice and gas in quiescent clouds
- Variable Young Stellar Objects Survey (VYSOS)
- Water on Mars
- X-ray- and UV-bright low-mass stars in the solar neighborhood