Igor Beresnev Research Projects

My interests lie in the fields of earthquake seismology, applied geophysics, wave propagation, fluid dynamics, and digital-data processing.

In seismology, I am mostly interested in various aspects of earthquake ground motions, such as simulation of fault radiation or studies of amplification of seismic waves by sedimentary layers, and earthquake-source physics in general.  Working with digital seismic data involves a great deal of computer programming, in which I often rely on myself, since many non-traditional data-processing tasks do not leave other choice.  I co-authored a computer code FINSIM (in collaboration with Dr. Gail Atkinson, University of Western Ontario, Canada, www.uwo.ca/earth/people/faculty/atkinson.html), which calculates seismic radiation from rupturing faults and is currently used in over 140 institutions in 36 countries.  My interests also involve nonlinear elasticity of earth materials and observation and modeling of nonlinear effects in seismic-wave propagation.

I study the effects of seismic waves and vibrations on the flow and mobilization of entrapped organic fluids (such as oil or organic contaminants) in geologic formations.  This research aims at developing field technologies of enhanced petroleum recovery or aquifer remediation using seismic and acoustic stimulation .  We are focusing on the fundamental aspects of fluid dynamics of immiscible two-phase flow in the presence of vibrations, with the intent to elucidate the mechanisms by which the vibrations mobilize the non-wetting fluids (related articles: Geophysics 59, 1994; Journal of Geophysical Research 108 (B3), 2003; Geophysical Research Letters 32, 2005; Geophysics 71, 2006).

A related subject that I have started to investigate recently is the capillary instability that causes the break-up of non-wetting  fluids into droplets in porous channels. 

My applied-geophysics agenda revolves around using our multichannel-seismic, multi-electrode electrical-resistivity, and ground-penetrating radar (GPR) systems for shallow-subsurface exploration.  The examples of recent work include prospecting for new sand-and-gravel deposits (related article: Journal of Applied Geophysics 49, 2002) or GPR applications to the assessment of road quality.

Current and Recent Sponsored Projects

Sonic stimulation of reservoirs and aquifers

Since 2002, this subject has continuously been supported by awards from the National Science Foundation, Petroleum Research Fund, and Department of Energy. 

All projects have a common goal of developing the physical foundations of the technologies of sonic stimulation of reservoirs and aquifers.  We focus on the basic capillary physics explaining the pore-scale mechanism of organic-fluid mobilization in rock by seismic waves and vibrations, through theoretical and laboratory studies. The studies are performed by our multidisciplinary collaborating team of scientists from the Department of Geological & Atmospheric Sciences and Department of Chemical & Biological Engineering.  The theoretical and numerical modeling is primarily conducted at the Department of Geological & Atmospheric Sciences by Igor Beresnev, Robert Ewing (www.agron.iastate.edu/soilphysics/ewing.html), and Ph.D. student  Wen Deng.  The laboratory work uses the techniques of visualization of fluid-flow in porous volumes allowing direct observation of pore-scale effects produced by vibrations.  The experiments are carried out by my partner Prof. Dennis Vigil (www.cbe.iastate.edu/vigil.html) and our joint Ph.D. student William Gaul at the Department of Chemical & Biological Engineering.

A recently completed DOE project, on which I collaborated with Michigan Technological University, emphasized field observations of sonically enhanced oil production (www.geo.mtu.edu/spot/SPOTProjects.htm).

Applied geophysics

2002-2004 "Interaction between land vibrator baseplate and ground surface". Sponsor: WesternGeco.

This industry-sponsored project has looked into improving the quality of deep seismic imaging in oil exploration through better understanding the Vibroseis source. Seismic vibrators are the most common sources of seismic energy in land exploration; however, the physics of Vibroseis radiation is not satisfactorily understood. For example, we have worked on the subjects of how ground nonlinearity around the vibrating plate and non-rigidity (flexing) of the plate affected the outgoing waves. Andrey Lebedev, a research scientist from the Institute of Applied Physics, Nizhniy Novgorod, Russia, has been working with me on the theory and modeling of these phenomena (related articles: Geophysics 69, 2004; Geophysical Prospecting 53, 2005; Geophysics 71, 2006).

Graduate Students
 

• Wen Deng (Ph.D.) is involved in computational fluid dynamics related to the simulations of (1) the effect of vibrations on two-phase pore-fluid flow and (2) the break-up of pore fluids into droplets.  
   
• William Gaul (Ph.D.) conducts parallel laboratory experiments to verify the theoretical and computational predictions of the vibratory-mobilization and break-up phenomena.  

Geophysical Equipment Resources

With our state-of-the-art equipment, we are capable of conducting precise geophysical surveys.  My geophysics lab is equipped with a Geometrics StrataView 24-channel engineering seismograph, ideal for detailed seismic-refraction and reflection studies. The lab also includes a multi-electrode resistivity system ResiStar RS-100M and a Noggin 250/500 MHz ground-penetrating radar, which provide unique possibilities for high-resolution subsurface imaging.  All the equipment is used in research and teaching and is available for independent graduate-student projects.  Students from the Departments of Geological & Atmospheric Sciences, Civil & Construction Engineering, and Agricultural & Biosystems Engineering have been among its users.