Jason D Gulley
Research Assistant Professor, Geological and Mining Engineering and Sciences
- PhD Geology, University of Florida
- BA Geology, Eastern Kentucky University
I am primarily interested in understanding self-organizing hydrological systems in glaciers and ice sheets, as well as in carbonate aquifers. My research methodologies bridge the fields of geomorphology, physical hydrology and aqueous geochemistry.
Ice dynamic processes currently account for > 50% of Greenland Ice Sheet (GrIS) mass loss and sea level rise of 0.75 mm a-1, but this contribution is increasing. Because the physical processes controlling ice dynamic processes are poorly understood, they generate the largest source of uncertainty in predictive models of sea level rise that are needed to develop management strategies for coastal water resources.
My research in glacier hydrology seeks to understand the physical processes responsible for coupling between the GrIS’s hydrological system and ice velocity (the ‘Zwally Effect’). Each melt season, GrIS velocities increase 50-300% over winter values when melt water is not present. This increase is thought to be regulated by annual cycles of conduit formation and collapse that regulate subglacial water pressure, and hence basal friction. Because of limited subglacial access, processes controlling these cycles are poorly known.
Most of my research on glacier hydrological systems is field based and draws upon my background in karst hydrology and geomorphology. I frequently use caving techniques to make observations and install instrumentation in glacier caves. My work in this area has taken to me to glaciers in Alaska, Svalbard and Nepal as well as to the Greenland Ice Sheet.
Carbonate Aquifer Hydrology
My research on modern carbonate platforms investigates how the development of surface water during sea level high stands, and the loss of surface water during low stands, affect patterns of groundwater circulation and post-depositional porosity generation in carbonate platforms.
Carbonate aquifers supply more than 25% of the world’s population with drinking water and understanding the processes that control groundwater circulation in modern carbonate platforms is therefore fundamental for fresh water resource management. Additionally, more than 60% of the world’s known hydrocarbon reserves are located in carbonate reservoirs. Understanding the processes that enhance porosity and permeability in modern platforms can make the locations of enhanced porosity and permeability in carbonate reservoirs more predicable, improving models of fluid flow in reservoirs.
Most of my research on carbonate aquifers is field-based and I frequently use cave diving techniques to make observations or install instrumentation in underwater caves. My recent research on carbonate platforms has been conducted in Florida, the Bahamas Islands and the Yucatan Peninsula.
Core research areas
- hydrogeology, particularly of karst aquifers, and glaciology
Specific current research interests include:
- How sea level fluctuations and climate change affect groundwater circulation and the formation of post depositional porosity in carbonate platforms
- How interactions between surface and groundwater affect dissolution, fluid flow and ecohydrology in carbonate platforms
- Physical processes responsible for dynamic coupling between glacier hydrology and ice motion with implications for understanding rates of sea level rise
- Gulley, J., Martin, J., Moore, P., and Murphy, J., In press. Formation of phreatic caves in an eogenetic karst aquifer by CO2 enrichment at lower water tables and subsequent flooding by sea level rise. Earth Surface Processes and Landforms. Read More
- Gulley, J., Martin, J., Spellman, P., Moore, P., and Screaton, E., In press. Influence of partial confinement and Holocene river formation on groundwater flow and dissolution in the Florida carbonate platform. Hydrological Processes. Read More
- Gulley, J., Walthard, P., Martin, J., Banwell, A., Benn, D., Catania, G., 2012. Conduit roughness and dye trace breakthrough curves: why slow velocity and high dispersivity may not reflect flow in distributed systems. Journal of Glaciology 58(211): 915-925. Read More
- Gulley, J., Grabiec, M., Martin, J.B., Jania, J., Catania, G., and Glowacki, P., 2012. The effect of discrete recharge by moulins and heterogeneity in flow path efficiency at glacier beds on subglacial hydrology, Journal of Glaciology 58(211): 926-940. Read More
- Benn, D.I., Bolch, T., Dennis, K., Gulley, J., Luckman, A., Nicholson, K.L., Quincey, D., Thompson, S., Tourni, R., and Wiseman, S., 2012, Response of debris-covered glaciers in the Mount Everest region to recent warming and implications for outburst flood hazards, Earth Science Reviews. 114(1-2): 156-174. Read More
- Martin, J., Gulley, J., *Spellman, P., 2012, Tidal pumping of water between Bahamas blue holes, the aquifer and the ocean. Journal of Hydrology 416-417: 28-38. Read More
- Covington, M.D., Banwell, A.F., Gulley, J., Saar, M.O., Wicks, C.M., Willis, I., Arnold, N., 2012, Quantifying the effects of recharge and system geometry on proglacial hydrograph form, Journal of Hydrology 414: 59-71. Read More
- Gulley, J., Martin, J., Screaton, E., Moore, P., 2011, River reversals in karst springs: a model for cave enlargement in eogenetic karst aquifers. GSA Bulletin. 123(3-4): 457-467. Read More