Home , Go Back to faculty page MARTIN O. SAAR Assistant Professor and Gibson Chair of Hydrogeology and Geofluids PhD, 2003, University of California-Berkeley For more detailed information, please click on: Martin Saar's Geofluids Research Group Web Page Office: 21 Pillsbury Hall Phone: (612) 625-7332 Fax: (612) 625-3819 Email: saar@...

    My primary interest is in studying the role of fluids in geological and geophysical processes with an emphasis on hydrogeological and/or volcanological phenomena. So the first immediate question is: "What is a fluid and what is a solid in general and in the geosciences in particular?" To answer this seemingly simple question it is necessary to consider the time scale of interest. For example, the Earth's mantle behaves like an elastic solid as earthquake waves travel through it within minutes but acts as a convecting fluid, driving plate tectonics, on time scales of thousands to millions of years. Thus, numerous processes in the Earth sciences may be viewed as fluid-mechanical phenomena given appropriate time scales of interest.

     My Geofluids Research Group develops and/or employs numerical (computer) models, analytical (mathematical) methods, as well as laboratory tests and experiments, to study geofluids over a wide range of spatial and temporal scales. We also conduct some field work to collect (rock, water, lava, ...) samples or to collect (heat flow, permeability, ...) data. Our studies are typically related to groundwaters, hydrocarbons, magmas, lavas, and/or (bubbly) suspensions and these fluids' roles in mass and energy (e.g., heat, pressure) transfer. Typical research topics therefore include 1) groundwater flow, 2) coupled groundwater, heat, noble gas, and/or contaminant transfer, 3) geothermal energy resources, 4) multiphase-multicomponent fluid flow, 5) poroelasticisty and hydroseismicity, 6) percolation theory and Lattice-Boltzmann simulations, 7) CO2 sequestration, 8) magma, lava, and suspension rheology and permeability, and 9) lava flow emplacement and volcanic eruption dynamics.

     Our research is particularly challenging and exciting because geofluids can behave very differently in a given stress tensor field. For instance, fluids can exhibit Newtonian, Bingham, Maxwell-solid, or any other type of rheological behavior and thus combine properties of both fluids and solids. In addition, their rheology is often extremely time-dependent, for example in the case of cooling or depressurizing magma where crystallization can be significant. Similarly, groundwater flow processes can vary with time as permeabilities increase or decrease for example due to fracture development or mineral precipitation, respectively. Flow regimes we encounter range from laminar to extremely turbulent.

     Our research approach, combining field, laboratory, and numerical methods, is possible due to two dedicated geofluids laboratories: a wet lab and a computer lab. The wet lab allows performance of experiments involving water, corn syrup, suspensions, and other analog fluids. The computer lab includes a multi-processor Linux cluster and several Linux and Windows PCs. When necessary, a fast ethernet connection provides access to additional processors at the Minnesota Super Computing Institute nearby.

     I encourage prospective students and postdocs with interests and backgrounds in geology, hydrogeology, volcanology, tectonics, sedimentology, (geo)physics, (geological) fluid mechanics, computer science, numerical methods, or multi-phase fluid flow to consider working in my Geofluids Research Group. The formation of this group is made possible by the generous endowment from George and Orpha Gibson as well as other resources such as the National Science Foundation and the University of Minnesota.

• 2003-04, Turner Postdoctoral Fellowship, University of Michigan
• 2005-present, Gibson Chair in Hydrogeology

• American Geophysical Union (AGU)
• Geological Society of America (GSA)
• International Association of Hydrogeologists (IAH)

  Courses Taught

• GEO 1001: Earth and Its Environments
• GEO 3203: Geodynamics II: The Fluid Earth
• GEO 4010: Coupled Heat and Fluid Flow in the Earth's Crust
• GEO 4971: Hydrogeology Field Camp
• GEO 5205: Fluid Mechanics in Earth and Environmental Sciences
• GEO 5701: General Hydrogeology
• GEO 8980: Coupled Heat and Fluid Flow in the Earth's Crust
• GEO 8980: Seminar: Volcanology

  Current Graduate Students

• Judy Andrews (MS-track, start date: fall 2004)
• Ravi Appana (PhD-track, start date: fall 2005)
• Maria Davis (PhD-track, start date: fall 2006)
• Jimmy Randolph (PhD-track, start date: fall 2006)

  Selected Publications

• Walsh*, S.D.C., and M.O. Saar, Numerical Models of Stiffness and Yield Stress Growth in Crystal-Melt Suspensions, Earth Planet. Sci. Lett., doi:10.1016/j.epsl.2007.11.028, Online: 2007, Print: 2008.
• Edwards, R.A., B. Rodriguez-Brito, L. Wegley, M. Haynes, M. Breitbart, D.M. Peterson, M.O. Saar, S. Alexander, E.C. Alexander Jr., F. Rohwer, Using pyrosequencing to shed light on deep mine microbial ecology under extreme hydrogeological conditions, BMC Genomics, doi:10.1186/1471-2164-7-57, 2006.
• Christiansen, L., S. Hurwitz, M.O. Saar, S.E. Ingebritsen, P. Hsieh, Seasonal seismicity at western United States volcanic centers, Earth. Planet. Sci. Lett., in press since Sep. 2005.
• Saar, M.O., M.C. Castro, C.M. Hall, M. Manga, and T.P. Rose, Quantifying magmatic, crustal, and atmospheric Helium contributions to volcanic aquifers using all stable noble gases: Implications for magmatism and groundwater flow, Geochem. Geophys. Geosyst., Vol. 6, Nr. 3, Q03008, doi:10.1029/2004GC000828, 2005.
• Jellinek, A.M., M. Manga, and M. O. Saar, Did melting glaciers cause volcanic eruptions in eastern California? Probing the mechanics of dike formation, J. Geophys. Res., Vol. 109, Nr. B9, B09206, doi:10.1029/2004JB002978, 2004.
• Saar, M.O. and M. Manga, Depth dependence of permeability in the Oregon Cascades inferred from hydrogeologic, thermal, seismic, and magmatic modeling constraints, J. Geophys. Res., Vol. 109, Nr. B4, B04204, doi:10.1029/2003JB002855, 2004.
• Saar, M.O. and M. Manga, Seismicity induced by seasonal groundwater recharge at Mt. Hood, Oregon, Earth Planet. Sci. Lett., Vol. 214, 605-618, 2003
• Saar, M.O. and M. Manga, Continuum percolation for randomly oriented soft-core prisms, Phys. Rev. E, Vol. 65, 056131-1 to 6, 2002.
• Saar, M.O., M. Manga, K. Cashman, and S. Fremouw, Numerical models of the onset of yield strength in crystal-melt suspensions, Earth Planet. Sci. Lett., Vol. 187, 367-379, 2001.
• Saar, M.O., and M. Manga, Permeability-porosity relationship in vesicular basalts, Geophys. Res. Lett., Vol. 26, No. 1, 111-114, 1999.

2007-2009: NSF (PI): Multiscale multiphase flow simulations of dense vesicular particle suspensions. 2-year grant: DMS-0724560

2005-2008: NSF (PI): Determining Large-Scale Permeability of Magma From its Bubble and Crystal Microstructure - A Multiphase Percolation Theory Approach. 3-year grant: EAR-0510723

2005-2010: Endowment from George and Orpha Gibson for the chair of hydrogeology and geofluids, U. of Minnesota

2006-2007: Grant-in-Aid funding for junior faculty from the University of MN

2005-2007: Startup funds from the Department of Geology and Geophysics and IT College, U. of Minnesota