I am interested in crustal structure of various geological environments. My early work focused on the formation of oceanic crust at mid-ocean ridges, and I am continuing this work with a project to correlate the geologic structure observed at Hess Deep and the Blanco Fracture Zone with the seismic structure observed at the adjacent plateaus. Since my employment at UTIG I have expanded my interests to the structure of subducting crust near Costa Rica and Barbados, the size and morphology of the Chicxulub impact crater, the nature of the crust within Bransfield Strait, the arc-continent collision zone in the SE Caribbean, terrane accretion in SE Alaska, and the rifting history of the Gulf of Mexico. In order to characterize the structure in these various environments I collect wide-angle seismic data using a large air-gun source and ocean bottom seismograph receivers; this is often done in conjunction with the acquisition of multi-channel seismic reflection profiles. I then use various techniques, including 1D reflectivity modeling, 2D ray-tracing, 2D and 3D tomography, and full waveform tomographic inversion to constrain crustal structure.

Areas of Expertise

Marine seismology, mid-ocean ridge structure and emplacement processes, oceanic crustal structure, ocean-bottom seismology, seismic refraction


Research Locations



Distinguished Lecturer - Consortium for Ocean Leadership (2010 - 2011)

Member, U.S. Advisory Committee for Scientific Ocean Drilling (USAC), Consortium for Ocean Leadership (2011 - 2013)

Associate Editor, Journal of Geophysical Research, AGU (2009 - 2013)

Member, Internship Selection Committee, IRIS (2009 - 2010)

Member, Ocean Bottom Seismometer Instrument Pool (OBSIP) Oversight Committee, NSF (2006 - 2012)

Member, Science Steering and Evaluation Panel (SSEP), IODP (2006 - 2008)

Member, Site Survey Panel, JOIDES (1997 - 2000)

Graduate Students

Mark H Duncan, M.S., expected 2013

Robert S Reece, Ph.D., expected 2013

Yi Tao, Ph.D., expected 2013

Drew R Eddy, Ph.D., expected 2014

Margaret Kroehler, M.S., 2007

Trevor Aitken, M.S., 2005


Site Surveys for IODP Expeditions, Future Scientific Ocean Drilling: A Workshop for Early Career Scientists, College Station, TX (2011)

Chicxulub Crater: What an Impact!, Texas A&M University, College Station, TX (2011)

Chicxulub Crater: What an Impact!, University of South Dakota, Vermillion, South Dakota (2011)

Chicxulub Crater: What an Impact!, University of Wyoming, Laramie, Wyoming (2011)

Chicxulub Crater: What an Impact!, University of Oklahoma, Norman, Oklahoma (2011)

Chicxulub Crater: What an Impact!, University of Wisconsin, Madison, Wisconsin (2011)

Chicxulub Crater: What an Impact!, University of Missouri, Kansas City, Missouri (2010)

Chicxulub Crater: What an Impact!, Tulsa University, Tulsa, Oklahoma (2010)

Chicxulub Crater: What an Impact!, Kent State University, Kent, Ohio (2010)

Chicxulub Crater: What an Impact!, Purdue University, West Lafayette, Indiana (2010)

Correlation of Seismic and Geologic Boundaries in Upper Oceanic Crust, Lamont-Doherty Earth Observatory, Palisades, New York (2006)

Comparison of Geologic and Seismic Structure of Intermediate and Fast-Spreading Crust, Duke University, Durham, North Carolina (2005)