River Kwai, Kanchanaburi, Thailand
Hello visitor! I am an Assistant Professor in the Department of Geological Sciences at California State University, Bakersfield. I got my Ph.D. in 2017 from Penn State, then I did my postdoc at Utrecht University before coming to Bakersfield.
Very broadly, I am interested in lithospheric deformation processes (basically, how the upper ~100 km of the Earth bends, breaks, and flows), and particularly how this deformation relates to earthquake cycles and seismic hazards.
If you are interested in these topics, I am looking for motivated master's and undergraduate students to work on research projects with me! Email me at mherman2 (at) csub (dot) edu for more information!
I also enjoy sharing my science as widely as possible (if you ever sit next to me on a plane, you will find that out quickly). Check out my Meet the Expert talks on earthquake magnitudes and earthquake triggering at the Buena Vista Museum of Natural History and Science in Bakersfield, or my talk on historical records of San Andreas earthquakes at the Ridge Route Museum in Frazier Park!
A magnitude 7.8 earthquake struck near Kaikoura Peninsula in New Zealand on November 13, 2016. This event broke at least 20 faults at the surface, making it one of the most complex events ever seen. Some of the faults shifted the ground by over 10 meters, more than nearly any other similar style earthquake of this magnitude. Intriguingly, although the earthquake began within the Pacific Plate, the extreme faulting only occurred after the earthquake crossed into the Hikurangi subduction zone.
We developed deformation models of the earthquake showing how a subduction zone earthquake under the surface faulting explains these observations. This plate boundary event triggered the surface faults and disconnected them from the rest of the Earth, allowing the ground to blow apart almost completely. This process is not limited to New Zealand. We propose that the reason we have not seen this in previous earthquakes is because this region of subduction zones usually lies underwater.
More about the Kaikoura earthquake...
My previous work focused conceptually on how locked zones in subduction zones affect slip on the plate interface around them. The main consequence is that regions adjacent to locked zones are held back by the asperity, even if they would otherwise be able to slide or otherwise deform at the relative plate motion rate. Slip deficit accumulates in these "pseudo-coupled" regions and can be released in earthquakes, but only along with their causative asperities.
The SZ4D initiative plans to instrument multiple subduction zones in order to resolve these locked zones in unprecedented detail. This will improve our ability to detect plate boundary slip. However, the degree to which locked zones can be distinguished by these improved datsets is not obvious. We are developing a suite of physics-based locking models to test the resolvability of locked asperities with different observation configurations, as well as the implications for interpreting earthquake behavior from these new datasets.
More about pseudo-coupling...