what we do

slow and Fast Earthquakes

We study earthquakes using mainly seismology. We record and analyze seismograms (record of ground vibrations produced by earthquakes) to better understand the physics of earthquakes and processes that control them. We work on large, damaging subduction plate boundary earthquakes to tiny local earthquakes. We are interested in better characterizing and understanding a broad spectrum of slip that we observe. In particular, we have pioneered work on slow earthquakes, a relatively new branch of earthquake science. Slow earthquakes are critical to understanding fault slip dynamics, earthquake nucleation and estimating earthquake hazard. We develop new techniques to detect, locate and track slow earthquakes in high resolution. Typically, we conceive and design seismic experiments in an attempt to answer scientifically interesting questions, go to the field to install seismic stations, record new seismic data, analyze them, produce results and interpret them to come up with an answer. We specializes in seismic array techniques in various space and time scales. Our approach provides members of this group opportunity to do interesting science with options and flexibility to travel distant places, explore nature and and/or work in an office setting.

Check out our research page

The Team



Dr. Abhijit Ghosh
Assistant Professor
University of California Riverside


Shukei Ohyanagi

Lisa Cahn

Previous Members

Tiffany Chu

Eduardo Huesca Perez

PhD Student

Abhijit Ghosh
a.k.a. Obi

I am an earthquake seismologist. The broad goal of my research is to better understand the physics of earthquakes, the processes that control them, and their associated hazards by examining a wide spectrum of fault slip across a broad range of spatial and temporal scales. I use seismograms, ground vibrations created by earthquakes and recorded by seismometers, as my main tool.

Assistant Professor
Department of Earth Sciences
University of California, Riverside 

Office:Geology Building
Room #438A
Riverside, CA, 92521

Office Phone:  +1 951 827 4493

Bo Li
o.k.a. Bo

I study the rupture process of large earthquakes and the hidden aftershocks following the mainshocks. I combine multiple arrays to improve the resolution and get higher accuracy of the source locations. I am also interested in behavior of slow slip events, such as the non- volcanic tremor and low frequency earthquakes. I try to explain the distribution and propagation of tremors and LFEs, and their potential relationship to the regular earthquakes.

My Publications
Li, B., & Ghosh, A. (2017). Near‐continuous tremor and low frequency earthquake (LFE) activities in the Alaska‐Aleutian subduction zone revealed by a mini seismic array. Geophysical Research Letters. [PDF]

Li, B., and A. Ghosh (2016), Imaging Rupture Process of the 2015 Mw 8.3 Illapel Earthquake Using the US Seismic Array, Pure Appl. Geophys., doi:10.1007/s00024-016-1323-y. [PDF]

Alexandra Hutchison
a.k.a. Allie

My interest lies in how to use slow earthquakes as a toolset to better understand stress dynamics along faults. In particular, my projects involve cataloging and analyzing very low frequency earthquakes (VLFEs) in Cascadia and investigating tectonic tremor near the Anza Gap in the San Jacinto Fault. Slow earthquakes require the application of non-traditional detection and location methods and my research allows me to explore a diverse set of such techniques including beamforming, multi-beam backprojection, envelope cross correlation, match filtering, and centroid moment tensor inversion.

When I'm not working, I can be found eating cheese, playing with my dogs, watching live music or stand up, jogging, or involving myself in some flavor of spontaneous adventure.

My Publications

Hutchison, A. A., & Ghosh, A. (2016). Very low frequency earthquakes spatiotemporally asynchronous with strong tremor during the 2014 episodic tremor and slip event in Cascadia. Geophysical Research Letters, 43(13), 6876-6882.

*Hutchison, A. A., and A. Ghosh (2016), Tectonic tremor in the San Jacinto Fault, near the Anza Gap, detected by multiple mini seismic arrays, (in review, BSSA).

Hutchison, A. A., Cashman, K. V., Williams, C. A., & Rust, A. C. (2016). The 1717 eruption of Volcán de Fuego, Guatemala: Cascading hazards and societalresponse. Quaternary International, 394, 69-78.

Matthew Mendoza
a.k.a. Matt

Namaste, I am a Ph.D. student in the field of Geophysics from the University of California, Riverside; a growing, research-rich, and diverse campus situated between the comfort of the San Bernardino Mountains and the Pacific Ocean. It is also conveniently placed just 15 miles (24 km) from the San Andreas fault. As an undergraduate I was apart of the the California Alliance for Minority Program, as well as a College of Natural & Agricultural Science Ambassador.

A few hobbies of mine include craft beer and whiskey exploring, petting dogs, and back-packing. Mt. Whitney (elev. 14, 500 ft) is currently the highest peak that I have been on, and only hope to go on more such expeditions elsewhere on the planet as my level of experience grows over time.

My Publications

Kundu, B., Ghosh, A., Mendoza, M., Burgmann, R., Gahalaut, V. K., & Saikia, D. (2016). Tectonic tremor on Vancouver Island, Cascadia, modulated by the body and surface waves of the Mw 8.6 and 8.2, 2012 East Indian Ocean earthquakes. Geophysical Research Letters, 43(17), 9009-9017. 

Mendoza, M. M., Ghosh, A., & Rai, S. S. (2016). Dynamic triggering of small local earthquakes in the central Himalaya. Geophysical Research Letters, 43(18), 9581-9587.

Kuntal Chaudhuri
o.k.a. Kuntal

" The earth quakes and I become happier" - Sorry I am not being a sadist but that's what we seismologists do with or without a keen intention. My interest lies in the understanding the deep seated dynamics and the behavior of tremors in the San Andreas Fault. For my Masters thesis I worked upon the central part of India dealing with the velocity structure of the Narmada Son Lineament. I used receiver functions methodology for my analysis and combined the techniques of neighborhood algorithm and joint inversion for a robust velocity model.

Leaving aside seismology I am too passionate about music. In spite of not being the Mozart of music I am rather the Jack of a few trades.

My Anthem : Dream On by Aerosmith

My Publications
Chaudhuri, K., Borah, K., & Gupta, S. (2016). Seismic evidence of crustal low velocity beneath Eastern Ghat Mobile Belt, India. Physics of the Earth and Planetary Interiors, 261, 207-216.