Monica D. Kohler
Senior Research Fellow in Mechanical and Civil Engineering
Dept. of Mechanical and Civil Engineering
229 Thomas Bldg., M/C 104-44
California Institute of Technology
Pasadena, CA 91125
Phone: (626) 395-4142
Harvard University, B.A., 1988
California Institute of Technology, Ph.D., 1995
My earthquake engineering research is focused on examining the wave propagation response of civil structures through numerical and observational experiments using earthquake and ambient vibration waveform data from dense sensor deployments. Projects related to this include
- Structural monitoring through community participation in the Community Seismic Network and Quake-Catcher Network projects that involve members of the community who host small, inexpensive seismometers in order to achieve deployments of tens of thousands of sensors in seismically active regions.
- Computing impulse response functions of the moment-frame UCLA Factor building using local earthquakes recorded on its 72-channel embedded strong-motion seismic array and simulations with a finite-element model of the building.
- Developing and testing a new, high-frequency method of detecting a failure event in engineered structures that uses the properties of reciprocity and time-reversed reciprocal Green's functions.
- Development of ShakeNet, a wireless Stargate-mote, tiered, seismic structural network that can be deployed on civil structures with no existing infrastructure for monitoring structural state of health.
My observational seismology work has the objective of constructing a geophysical framework that describes the rheologial, dynamic, and kinematic environments that lead to initiation and evolution of young continental collisional and tranpressional plate boundaries. Projects motivated by this include:
- 3D seismic tomographic modeling of crustal and mantle lithosphere beneath young transpressional plate boundary systems with application to the Transverse Ranges in southern California, and the Southern Alps in South Island, New Zealand.
- Using data from a 12-month deployment of ocean bottom seismometers off the coast of southern California in 2010-2011 to study local seismicity, upper mantle seismic structure, and Tohoku tsunami wave propagation.
- Relating plate boundary dynamics below southern California to lateral variations in San Andreas fault propeller-like geometry.
- Examination of upper mantle seismicity in region of active continent-continent collision, Southern Alps, South Island New Zealand.
Within both these disciplines, my studies have provided evidence for the types of failure and deformation mechanisms that can occur within the brittle-plastic spectrum of these systems, particularly within transition regions.