Sampling the Source of the 2011 Japan Earthquake and Tsunami by Dr. Frederick Chester

March 18, 2014

Dr. Frederick Chester is a U. S. Science Support Program Distinguished Lecturer. As part of the lecture series, Dr. Chester spoke at St. Thomas on Thursday, April 10, Noon – 1:00 p.m., in the 3M Auditorium (OWS 150). His lecture is titled, “Sampling the Source of the 2011 Japan Earthquake and Tsunami.”

Here is a stream of that lecture: 

https://stream.stthomas.edu/view?id=b4886d4e572c44b4bf902c2d5e9eca56

Sampling the Source of the 2011 Japan Earthquake and Tsunami - Lecture information here: http://usssp-iodp.org/lecture/chester/

The fault slip during the 2011 Tohoku-oki earthquake, which reached over 50 meters near the Japan Trench, is the largest observed, and it is responsible for the tsunami that devastated the coast of northeast Honshu, Japan. Although the cause of significant seismic slip at shallow depths is not entirely understood, a number of possible contributing factors have been identified. Key questions include how displacement was accommodated near the trench, and whether coseismic weakening of the shallow megathrust had a role in the mechanics of such large displacement. These and other questions were addressed by the Japan Trench Fast Drilling Project, Expedition 343/343T, undertaken by the Integrated Ocean Drilling Program (IODP). Drilling the plate boundary interface was technically challenging because of the 6.9 km water depth and the need to penetrate > 800 m through the prism to reach the subducting plate. Nonetheless, three successful holes were drilled to the target depth for geophysical logging, coring, and placing instruments across the fault to measure the frictional heat produced during the earthquake. I will summarize the scientific motivation for the rapid response expedition, the challenges that were overcome, and the truly unique findings that shed light on the Tohoku-oki event and other tsunamigenic subduction zones worldwide.

Dr. Chester is a professor of Geology & Geophysics at Texas A&M University. His research focuses on the mechanics of fracture and faulting, physics of the earthquake source, fault-rock fabrics, granular and poroplastic behaviors, fluid-flow properties of deformed rock, deformation assisted by fluid-rock reactions, and constitutive modeling through experimental rock deformation, field study, and theoretical modeling. He served as a structural geologist on IODP Expedition 316 of the Nankai Trough Seismogenic Zone Experiment and as co-chief scientist on the Japan Trench Fast Drilling Project, IODP Expedition 343/3437.

Flyer for this event: 

 ‌Geology Lecture April 10 2014

SCIENCE Vol 342, 6 Dec 2013, Report: Structure and Composition of the Plate-Boundary Slip Zone for the 2011 Tohuku-Oki Earthquake: 

SCIENCE Report of 2011 Tohuku-Oki Earthquake