Home , Go Back to faculty page WILLIAM E. SEYFRIED, JR. Professor PhD, 1977, University of Southern California Office: 104C Pillsbury Hall Phone: (612) 624-1333 Fax: (612) 625-3819 Email: wes@...

     My main research interests involve assessment of geochemical processes responsible for the chemical evolution of aqueous fluids in and on the Earth. Thus, I study mineral dissolution and precipitation processes together with the reaction rates of minerals in complex aqueous fluids at a wide range of temperatures and pressures. The approach I emphasize in the course of these studies typically involves experimental and theoretical modeling, in conjunction with analysis of field data from natural hydrologic and hydrothermal systems.

Deployment from DSRV ALVIN of electrochemical sensor array developed at UM. Vent fluid temperature is approximately 365°C and seafloor pressure is 250 bar (P vent, 9° 50'N EPR, 2/05/05).

Although initially focused on inorganic chemical systems, recent experiments have been directed towards organic systems involving microbial metabolism in deep-sea vents and the role of mineral catalysis on hydrocarbon formation in hydrothermal vent fluids. Hydrocarbons synthesized in the hydrothermal experiments not only relate well to modern geochemical and biological systems at mid-ocean ridges, but may also provide clues for the mechanism of formation of even more complex organic molecules (amino acids, lipids) in ancient, pre-biotic hydrothermal systems on Earth and elsewhere.

     Moreover, the aqueous geochemistry group at the University of Minnesota has played an important role in the development of new experimental hydrothermal techniques that have resulted in novel chemical sensors to investigate the in-situ chemistry of aqueous fluids at elevated temperatures and pressures. Although initially designed to determine the distribution of aqueous species in complex fluids where theoretical models are lacking or inaccurate, it soon became clear that the lab-based sensors could be reconfigured for seafloor hydrothermal applications. Thus, in-situ sensors for measurement and monitoring dissolved components in high-temperature hydrothermal fluids were successfully developed and deployed in vent fluid systems on the Juan de Fuca Ridge (N.E. Pacific)(1999, 2005), East Pacific Rise, 9-10°N (2002, 2004) and the Galapagos Rift (2005) using DSRV ALVIN.  Indeed, these deployments have provided the first simultaneous in-situ data for pH, dissolved hydrogen and dissolved hydrogen sulfide, species critical to understanding geochemical reactions at depth in the ocean crust, as well as biogeochemical processes in the near-vent environment. Future research cruises and ROV investigations are planned for longer term monitoring studies of vent fluid chemistry at mid-ocean ridges and at hydrothermal vents on the floor of Yellowstone Lake, Wyoming. An overarching goal of these studies involves exploration of the interplay between chemical and physical processes that influence the origin and evolution of hydrothermal vent fluids and coexisting biologic communities in space and time.

• Geochemical Society
• American Association for the Advancement of Science
• American Geophysical Union
• Society of Economic Geologists
• Geological Society of America

• Oceanography
• Aqueous Geochemistry

• Doug Allen, PhD 2003
• Jennifer Houghton, PhD 2003
• Xian Chen, PhD 1998
• Christian Schardt, MS 1996 (Plan B).

• Foustoukos D. and Seyfried W. E., Jr. (2005) Redox and pH constraints in the TAG hydrothermal system: 26°N, Mid-Atlantic Ridge. Earth & Planetary Science Letters 235, 497-510.
• Kump L. R. and Seyfried W. E., Jr. (2005) Hydrothermal Fe fluxes during the Precambrian: Effect of low oceanic sulfate concentrations and low hydrostatic pressure on the composition of black smokers. Earth & Planetary Science Letters, 235, 654-662.
• Ding K., Seyfried W. E., Jr., Tivey M. K., Von Damm K. L., Bradley A. M., and Zhang Z. (2005) In-situ pH measurement of hydrothermal fluids at Mid-ocean ridges. Earth & Planetary Science Letters 237, 167-174.
• Allen D. E. and Seyfried W. E., Jr. (2005) REE controls in MOR hydrothermal systems: An experimental study at elevated temperature and pressure. Geochim. Cosmochim. Acta 69(3), 675-683.
• Foustoukos D. I., James R. H., Berndt M. E., and Seyfried W. E. J. (2004) Lithium isotopic systematics of hydrothermal vent fluids at the Main Endeavour Field, Northern Juan de Fuca Ridge. Chemical Geology 212, 17-26.
• Foustoukos D. I. and Seyfried W. E. (2004) Hydrocarbons in hydrothermal vent fluids: The role of chromium-bearing catalysts. Science 304 (5673), 1002-1005.
• Houghton J. L., Shanks W. C., and Seyfried W. E. (2004) Massive sulfide deposition and trace element remobilization in the Middle Valley sediment-hosted hydrothermal system, northern Juan de Fuca Rdge. Geochimica et Cosmochimica Acta 68(13), 2863-2873.
• Fu X. and Seyfried W. E., Jr. (2004) Hydrothermal Carbon Dioxide Reduction with Magnetite at 400°C and 500 bar. Proceedings of International Conference on Water-Rock Interaction (in-press).
• Allen D. E. and Seyfried W. E., Jr. (2004) Serpentinization and heat generation: constraints from Lost City and Rainbow hydrothermal systems. Geochimica et Cosmochimica Acta 68(6), 1347-1355.
• Seyfried W. E., Jr., Foustoukos D. I., and Allen D. E. (2004) Ultramafic-hosted hydrothermal systems at mid-ocean ridges: Chemical and physical controls on pH, redox and carbon reduction reactions. In The Thermal Structure of the Oceanic Crust and The Dynamics of Hydrothermal Circulation (ed. C. R. German, J. Lin, and L. M. Parson), pp. 267-284. American Geophysical Union.
• Seyfried W. E., Jr. and Shanks W. C. (2004) Alteration and mass transport in hydrothermal systems at mid-ocean ridges: Controls on the chemical and isotopic composition of axial vent fluid. In The Hydrology of the Oceanic Crust, Vol. (in-press) (ed. E. Davis and H. Elderfield). Cambridge University Press.

• NSF, In-situ sensors for monitoring the chemistry of hydrothermal fluids: Experimental calibration and field applications
• NSF, Geochemical constraints on light emission in seafloor hydrothermal systems: An experimental study using in-situ spectral and chemical techniques
• NSF, Geochemical Controls on the Composition of Coexisting Vapors and Brines: A Novel Approach to Assess Aqueous Speciation in Subseafloor Hydrothermal Systems
• American Chemical Society, Abiotic formation of hydrocarbons: an experimental investigation with application to natural hydrothermal systems
• DOE, A novel approach to experimental studies of silicate dissolution kinetics
• Petroleum Research Fund, Carbon and hydrogen isotopic composition of hydrocarbons
• Woods Hole Oceanographic Institute, In-situ perspectives on pH and redox variability of hydrothermal vent communities