Geology - Home
People
Harold J. Tobin
Associate Professor
Geophysics
(608)265-5796
Email: htobin@geology.wisc.edu
Office: 121 Weeks Hall


Department Links
The_Geoscience_Visualization_Center


Research

Nearly all the plate tectonic "action" on Earth takes place at the edges, where plates meet at major faults. These plate boundary faults are sites of active deformation, earthquakes, and are the source of tsunami, but we still don't understand many fundamental things about how they work.

I am interested in the internal properties of active faults at the Earth's plate boundaries - for example, subduction zones in the Pacific Ocean and the San Andreas fault in California. In my research, I combine direct sampling of faults deep beneath the surface of the Earth - through drilling at sea and on land - with detailed 3D seismic reflection imaging of the fault architecture and properties. Laboratory experiments on the mechanics and physics of the fault rocks completes the link among these different ways of "seeing" into active fault zones.

My major effort is as co-Chief Project Scientist of the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE), a years-long project to drill into and place instruments in the subduction zone plate boundary faults off the coast of Japan. NanTroSEIZE is part of IODP, the Integrated Ocean Drilling Program, and is the most ambitious and complex scientific drilling program ever undertaken.

A short video introducing the NanTroSEIZE project and my research (Deep-sea drilling in the Nankai Trough):

Click here for a segment from a Discovery Channel special about my research.

I am also involved in the San Andreas Fault Observatory at Depth (SAFOD) project, a study of the internal workings of the San Andreas through land-based drilling. My students and I are tackling laboratory experiments on friction and elastic properties of rocks from SAFOD cores to better understand the make-up of the fault zone.