************************************************************* ECOSSE Ph.D. studentship "Numerical simulations of hydromechanical dynamics in active volcano-hydrothermal systems" ************************************************************* From: Sebastian Geiger <Sebastian.Geiger@xxxxxxxxxxxx> Dear colleagues, We would like to advertise the ECOSSE Ph.D. studentship on "Numerical simulations of hydromechanical dynamics in active volcano-hydrothermal systems" to be carried out jointly at Heriot-Watt University and University of Edinburgh within the new Edinburgh Research Partnership "Edinburgh Collaborative On Subsurface Science and Engineering" (ECOSSE). This Ph.D. project aims at understanding, using numerical simulations and field data from Iceland, how earthquakes (remotely) change the permeability and hydrodynamics of the hot upper crust in volcano-hydrothermal systems. A detailed project description can be found below or in PDF format at http://www.pet.hw.ac.uk/aboutus/staff/pdfs/ecosse_phd.pdf. For further information, please contact Sebastian Geiger-Boschung at sebastian.geiger@xxxxxxxxxxxx and visit http://www.erp.ac.uk/ecosse/. Application details can be found at http://www.pet.hw.ac.uk/courses/research/phd.htm and http://www.pet.hw.ac.uk/courses/research/apply.htm We would appreciate if you could circulate this studentship among your students. Thanks a lot and best wishes, Sebastian Numerical simulations of hydromechanical dynamics in active volcano-hydrothermal systems It is well-known that earthquakes can cause abrupt changes in the groundwater flow patterns in volcano-hydrothermal systems (c.f. Manga and Brodsky, 2006). This is well-documented by field data that display rapid, post-seismic changes such as temperature fluctuations in mid-ocean ridge black-smoker vents (Johnston et al., 2000), water-level changes in deep wells (Roeloffs et al., 2003), and changes in geyser periodicity (Husen et al., 2004). Systematic changes in geothermal fluid chemistry have also been measured at Husavik (N. Iceland) before, during and after a major earthquake whose epicenter was about 90 km distant (Claesson et al., 2004). Traditionally, the hydrologic response following large earthquakes has been linked to changes in crustal stresses and transient permeability enhancement (Rojstaczer et al., 1995). These permeability changes appear to be more likely to occur in hot volcanic crust; for example, following major earthquakes in the western USA, triggered micro-earthquakes and pore pressure changes occurred at great distances (i.e., up to ~1250 km) from the epicenter, but were focused in areas of hot crust (Hill et al., 1993). Fluid flow in volcano-hydrothermal systems is often convective and hence very sensitive to small variations in permeability (Geiger et al., 2005). However, it is not well understood how large and rapid permeability variations cause local hydrothermal systems to respond to an earthquake or even to the stress change preceding an earthquake. This project will tackle three questions, by using numerical simulations carried out with our novel C++ finite element - finite volume code "Complex System Platform" (CSP): (i) How does an earthquake (remotely) alter the permeability in hot and weak fluid-saturated crust? (ii) What is the time-scale and magnitude of the permeability change? (iii) How can results from (i) and (ii) be applied to explain observed field data in Husavik, Iceland? To tackle these questions, the successful candidate will construct and run spatially and temporally high-resolution 2D and 3D models in CSP. He/she will implement the physical and/or chemical constitutive laws (e.g., permeability alterations due to stress and temperature changes) necessary to conduct physically realistic flow simulations. The outcome of this project will not only be of importance to geologists, geochemists, and geophysicists working in volcano-hydrothermal systems, but also has the potential to understand how field data could be used to predict when and where earthquakes will occur. The project will be ideal for a numerate geologist, physicist, or mathematician. The successful candidate will hold a masters (or equivalent) degree in one of these fields. He/she must be interested in multidisciplinary research that combines aspects of fluid mechanics, thermodynamics, geology, programming, and visualization. Training will be provided in the necessary multidisciplinary aspects of the project. Within the ECOSSE framework, the successful candidate will collaborate closely with geologists at the University of Edinburgh but also with the leading experts in hydrothermal fluid flow at Stockholm University, U.S. Geological Survey, Imperial College London, and ETH Zurich. The stipend is approximately £12,500 per annum and fees are covered. For further information, please contact Dr. Sebastian Geiger-Boschung at sebastian.geiger@xxxxxxxxxxxx and visit http://www.erp.ac.uk/ecosse. For application details, see http://www.pet.hw.ac.uk/courses/research/phd.htm and http://www.pet.hw.ac.uk/courses/research/apply.htm Claesson, L., A. Skelton, C. Graham, C. Dietl, M. Mörth, P. Torssander and I. Kockum, Hydrogeochemical changes before and after a major earthquake. Geology, Vol. 32, 641-644, 2004. Geiger, S., T. Driesner, C.A. Heinrich, and S.K. Matthäi, On the dynamics of thermohaline convection in the Earth's crust. Journal of Geophysical Research, Vol. 110, B07101, 2005. Hill, D.P., P.A. Raesenberg, A. Michael, W. Arabaz, G.C. Beroza, et al., Seismicity in the western United States remotely triggered by the M 7.4 Landers, California, earthquake of June 28, 1992. Science, Vol. 260, 1617-1623, 1993. Husen, S., R. Taylor, R.B. Smith, H. Healser, Changes in geyser eruption behavior and remotely triggered seismicity in Yellowstone National Park produced by the 2002 M 7.9 Denali fault earthquake, Alaska. Geology, Vol. 32, 537-540, 2004. Johnson, H.P., M. Hutnak, R.P. Dziak, C.G. Fox, I. Urcuyo, J.P. Cowen, J. Nabelekk and C. Fisher, Earthquake-induced changes in a hydrothermal system on the Juan de Fuca mid-ocean ridge. Nature, Vol. 407, 174-177, 2000. Manga, M., E. Brodsky, Seismic triggering of eruptions in the far field: Volcanoes and geysers. Annual Review of Earth and Planetary Science, Vol. 34, 263-291, 2006. Roeloffs, E., M. Sneed, D.L. Galloway, M.L. Sorey, C.D. Farrar, J.F. Howle, K. Hughes, Water-level changes induced by local and distant earthquakes at Long Valley caldera, California. Journal of Volcanology and Geothermal Research, Vol. 127, 269-303, 2003. Rojstaczer, S., S. Wolf, R. Michel, Permeability enhancement in the shallow crust as a cause of earthquake-induced hydrological changes. Nature, Vol. 373, 237-239, 1995. ============================================================== To unsubscribe from the volcano list, send the message: signoff volcano to: listserv@xxxxxxx, or write to: volcano-request@xxxxxxxx To contribute to the volcano list, send your message to: volcano@xxxxxxxx Please do not send attachments. ==============================================================
