I am interested in crustal structure of various geological environments. A continuing interest is in the structure of oceanic crust, and using seismic data to understand its formation and evolution. A key question I focus on is correlating seismic boundaries with geologic stratigraphy. Tectonic windows expose oceanic crust at fracture zones and propagating rifts, and I have carried out seismic experiments at 2 of these locations (Hess Deep and the Blanco Fracture Zone) to correlate seismic structure with geologic boundaries mapped by submersibles. Ophiolites are often studied to gain insights into oceanic crust, but are believed to be formed primarily in suprasubduction zone settings. I am currently studying the Izu-Bonin forearc, which is located in this type of tectonic setting. A new project will study evolution of slow-intermediate spreading rate crust in the South Atlantic via seismic and drilling data.

I am also interested in crustal structure at complicated tectonic settings. I have participated in seismic studies investigating 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 - 2014)

Associate Editor, Journal of Geophysical Research, AGU (2009 - 2015)

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

Maureen A Walton, Ph.D., expected 2016 (Committee Member)
The title of Maureen's dissertation is "Tectonic and sedimentary processes of the southeast Alaska margin." She is a part of the St. Elias Erosion/Tectonics (STEEP) team at the University of Texas Institute for Geophysics, studying both structural and geologic processes in the southeast Gulf of Alaska. The first chapter of her work focuses on the deposition of the Baranof deep-sea fan, and the other chapters involve earthquake tectonics and large-scale strike-slip plate motion.

Drew R Eddy, Ph.D., expected 2014 (Committee Member)

Mark H Duncan, M.S., expected 2013 (Co-supervisor)

Robert S Reece, Ph.D., expected 2013 (Committee Member)

Yi Tao, Ph.D., expected 2013 (Committee Member)

Margaret Kroehler, M.S., 2007 (Co-supervisor)

Trevor Aitken, M.S., 2005 (Co-supervisor)


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)