A Scientist’s Life: Wenyuan Fan

Wenyuan Fan is an assistant professor of geophysics at Scripps Institution of Oceanography at UC San Diego. He received his bachelor’s and master’s degrees from Peking University in 2008 and 2011, respectively. He received his PhD from Scripps Oceanography in 2017. After stints as a postdoctoral researcher and assistant professor, he returned to Scripps Oceanography in 2020.

explorations now (en): What do you do for a living?

Wenyuan Fan (WF):  I am a seismologist. I work on earthquakes and environmental processes. I try to understand how earthquakes rupture, how they nucleate, how they propagate, and how they interact with each other. And I also hope to understand what are the tectonic controls over earthquake processes.

I did some experiments in the ocean two years ago in a joint project with a lot of teams trying to understand oceanic transform faults near the East Pacific Rise. The reason we were interested in that topic and that region was that we were able to successfully forecast the occurrence of magnitude 6 earthquakes along those faults, so then the question came back to us why it was so predictable? We all understand that earthquakes in Southern California seem to be very difficult to predict at a given fault. We had about 50 instruments, ocean bottom seismometers, deployed in the region for about two years trying to understand the full evolution of the material properties, the stress, and also the seismicity, and hopefully trying to understand the physical mechanisms and processes leading up to an anticipated magnitude 6 event.

en: What are some of the main questions those in your field are trying to answer?

WF: For earthquake seismology, I think the biggest question on everyone's mind is how can you predict an earthquake or can you even predict an earthquake? A lot of the research now focuses on trying to understand how earthquakes start and perhaps more importantly, trying to understand how earthquakes stop rupturing. That differentiates small earthquakes and large earthquakes.

en: Describe the research you and other researchers at Scripps Oceanography have conducted on the February 2023 earthquakes in Turkey and Syria.

WF: In response to the recent Turkey-Syria earthquake, scientists here at IGPP (the Cecil H. and Ida B. Green Institute of Geophysics and Planetary Physics) collaborated to use seismic data and space geodetic data, as well as physics-based modeling, to investigate the rupture processes of the Turkey-Syria earthquakes.

Specifically, we hope to understand how the first event caused the second event. The two earthquakes were only separated by about nine hours. It was actually a doublet. The first event had a magnitude of 7.8 and the second event had roughly about the same magnitude at around 7.7 to 7.8. They were about 100 kilometers (60 miles) apart. That was one of the reasons why the damage was so severe because it was not just one, but two.

en: What are the tools you use in your research?

WF: I use data recorded by seismometers. I also deploy instruments, sometimes in the ocean, sometimes on ice, sometimes on land, and then process the data. I develop new algorithms and also do modeling using high-performance computing.

I use large-scale arrays, which means I use hundreds to thousands of stations to investigate seismic sources. They are covering the whole United States as well as part of the European continent.

en: What motivates your work?

WF: I enjoy my research and it’s very rewarding to answer interesting questions. Part of what motivates my work is related to hazards and doing fundamental research that's directly related to hazard mitigation, the knowledge or foundations for future models and technologies that might help people in near-real time.

Earthquakes are fascinating processes, right? It takes thousands of years or hundreds of years to accumulate the energy that would be released in seconds. It's a very large temporal span and spatially speaking, earthquakes can rupture from meters to thousands of kilometers. It’s a process that can happen over a broad range of spatial and temporal scales, so the physics are very complex because they have to work over the scales.

en: Why did you want to come to Scripps Oceanography?

WF: The colleagues here are amazing. It has been absolute fun to work with people here so that's certainly one of the highlights. Also, we have the beach!