People

Ryan M. Pollyea


Ryan M. Pollyea

Assistant Professor
Hydrogeology, Geostatistics
Office: 417-B1 Davis Hall
Phone: 815.753.7851
E-mail: rpollyea@niu.edu   Linked In

Educational Background

Ph.D., University of Idaho, 2012
B.S., University of Dayton, 1999

Research Interests

  • Continental-scale fluid flow
  • Geologic carbon sequestration
  • Reservoir heterogeneity
  • High performance computing
  • Geostatistical reservoir modeling

Research Activities >

Selected Publications >

Teaching >
 


Research Activities

My research area is generally described as physical hydrogeology, and I am specifically interested in the influence of reservoir heterogeneity on nonisothermal, multi-component and multi-phase systems. In pursuing my research, I deploy a suite of computational tools, including numerical models of heat and mass transport and geostatistical reservoir simulation. For situations where production software is not available to complete a given task, I enjoy writing code for specialized applications. To bridge the simulated and natural worlds, I investigate modeling results using principles from geomechanics, spatial analysis, and fluid mechanics to enhance our understanding of the physical processes governing complex hydrogeologic systems. Although this work is computational in nature, my research is based on high-quality field data obtained using a range of techniques from state-of-the-art (e.g., terrestrial LiDAR and field deployable laser absorption gas analyzers) to low-tech (e.g., manual fracture counts and homemade experiments).

Geologic carbon sequestration

1) Understanding the influence of fracture heterogeneity on geologic carbon sequestration in low-volume basalt reservoirs. This work focuses on understanding how the spatial distribution of fractures impacts CO2 injection pressure and geomechanical changes in a low-volume basalt reservoir.


2) Developing gradient-based methods for quantifying CO2 reservoir leakage a using portable laser absorption gas analyzer. We are currently analyzing time-series CO2 data from a field experiment to understand the differences between traditional CO2 flux monitoring and long-term soil CO2 concentration monitoring.

Continental-scale fluid flow

1) Orogenic fluid systems are governed by complex interactions between topographic driving potential, thermal gradients, prograde dehydration reactions, internal geologic structure, and regional tectonic forcing. We are currently using numerical models of idealized wedge systems to isolate various components of these fluid systems. The goal of this work is to understand the influence of taper angle on orogenic fluid system evolution with an emphasis on narrowly tapering orogenic wedges.


2) The Atacama Desert is the driest place on Earth receiving less than 10 mm of precipitation per year on average. As a result, salars and springs are the sole source of water within the region; however, the recharge system for these water sources is poorly understood. We are currently using a continental-scale numerical model of a transect through the high Andes into foreland basin (containing the Atacama Desert) to gain a first-order understanding of the mechanics governing groundwater recharge into these low elevation spring.

Graduate Students

Graduate students in my research group will learn traditional methods for groundwater investigations and gain exposure to new and exciting techniques for hydrogeologic site characterization. In addition to these skills, students in my group will become functional in a Unix/Linux environment, and may learn a computer programming language, if needed for their research. I encourage applications from students with broad scientific interests in groundwater and energy resources, modeling and simulation, applied mathematics, and a fair dose of fieldwork to keep us all honest!

Please contact me if you would like more information about my research program or current student opportunities.


Selected Publications

Pollyea, R.M., Fairley, J.P., Podgorney, R.K., and McLing, T.L. 2014. Physical constraints on geologic CO2 sequestration in low-volume basalt formations. GSA Bulletin. doi:10.1130/B30874.1, pre-publication available online January 7.

Pollyea, R.M., Fairley, J.P., Podgorney, R.K., and McLing, T.L. 2013. A field sampling strategy for semivariogram inference of fractures in rock outcrops.  Stochastic Environmental Research and Risk Assessment, Vol. 27, No. 7, p. 1735-1740, October.  doi:10.1007/s00477-013-0710-5.

Pollyea, R.M. and Fairley, J.P. 2012. Implications of spatial reservoir uncertainty for CO2 sequestration in low-volume basalt. Hydrogeology Journal, Vol. 20, No. 4, p. 689-699, April. doi:10.1007/s10040-012-0487-1

Pollyea, R.M. and Fairley, J.P. 2012. Experimental evaluation of terrestrial LiDAR- based surface roughness estimates. Geosphere, Vol. 8, No. 1, p. 1–7, February. doi:10.1130/GES00733.1

Pollyea, R.M. and Fairley, J.P. 2011. Estimating surface roughness of terrestrial laser scan data using orthogonal distance regression. Geology, Vol. 39, No. 7, p. 623–626, July. doi:10.1130/G32078.1


Teaching

  • Introductory Geology
  • Hydrogeology
  • Contaminant Hydrogeology (with Dr. Melissa Lenczewski)
  • Groundwater Modeling
  • Environmental Field Camp