Thomas J. Burbey

Associate Professor of Hydrogeosciences and Associate Department Chair

3049A Derring Hall

+1.540.231.6696 (Phone)

+1.540.231.3386 (FAX)

4044 Derring Hall (0420)
Blacksburg, VA 24061

B.S. Geology and Geophysics, 1981, University of Wisconsin-Madison
M.S., Hydrology/Hydrogeology, 1984, University of Nevada, Reno
Ph.D., Hydrology/Hydrogeology, 1994, University of Nevada, Reno

I have been interested in the aspects of aquifer deformation due to pumping since the early 1980's. The way evaluate deformation and assess aquifer properties has changed significantly since that time. We've gone from analytical one-dimensional elastic deformation calculations to sophisticated models of three dimensional models of coupled deformation and flow, from poroelasticity to poroviscosity, from measuring vertical deformation to measuring volume deformation. As a result our understanding of aquifer-system behavior due to pumping has increased greatly from these early days. We continue to advance the science by building better models, applying more sophisticated observational techniques, installing state-of-the-art sensors in the earth, and taking a multi-disciplinary approach in our understanding of earth-system processes. InSAR and GPS have now become the standard for measuring land subsidence. InSAR provides basin-wide coverage of temporal deformation and has helped us to better understand the role of faults and the occurrence of earth fissures. These techniques continue to advance how we measure subsience and interpret results.

Another important area of research is fluid flow and aquifer-system dynamics in complex fractured and faulted systems. We've been studying a complex metamorphic terrane in the Blue Ridge Province since 1996 and the more we learn about the nature of the system the more questions that arise. Currently, we are trying to understand the complex process of recharge to deep fracture systems. It appears that recharge occurs along selective pathways that are highly sensitive to structure in general, and in thrust faulting more specifically. It seems that the subcrop of many brittle fault structures provide highly conductive pathways for recharge into deeper aquifer systems. Most recharge is either lost to ET, flows through the shallow highly heterogeneous saprolite, or runs off to streams. The amount of recharge that actually enters the bedrock aquifers through fracture networks associated with weathering is probably very small compared to the recharge occurring along fault systems. We apply multiple techniques in our field research efforts including borehole logging using numerous downhole tools such as the heat-pulse flow meter, caliper, optical televiewer, resistivity, temperature and conductivity. We also make use of two and three dimensional surface resistivity to characterize the subsurface geology and hydrogeology. Our efforts are to better quantify the nature and rates of flow in these highly complex systems both at the local and eventually the regional scale.