California is a good place for a postdoctoral seismologist to work. It is one of the nation's most seismically active states, after all.
It wasn't until 2005, though, while at the University of California, Berkeley, that Gareth Funning felt his first earthquake. He was resting briefly in an office he shared with two other postdocs.
"I wondered if it was just me, but the other two just stopped talking, so I knew it was something real," he said. "Then they explained to me that that's what an earthquake felt like. It was about a magnitude 2, something you might not usually feel," he said. "But Berkeley is right on the Hayward fault."
It would be the first of several earthquakes he would feel now that he had moved to California from his native England, a land of comparatively low seismicity because it is far from the edge of a tectonic plate.
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How did Gareth end up as a seismologist in California, eventually specializing in the use of space-based techniques such as the U.S. Global Positioning System (GPS) and interferometric synthetic aperture radar (InSAR) to measure the displacement of the Earth's surface? When and how did that career path begin?
It began with an interest in geology as a young boy in Guildford, a city of about 143,000 people today and about 30 miles southwest of London in the county of Surrey.
On a family vacation to France, young Gareth set his eyes on the Massif Central, an extensive highland in southcentral France. It encompasses about 15% of the nation.
Most of the Massif Central is just highlands, but it does include two higher volcanic areas: the Massif du Sancy and the Monts du Cantal.
"What was really cool to me then was that the mountains looked like volcanoes, but they were green, just covered in grass and bushes, but they had volcano shapes," he said. "So this was amazing. I thought, 'Wow! Volcanoes.'
"So I did a middle-school project about volcanoes and earthquakes."
Back in London, a trip to the Natural History Museum sealed his seismology future. The museum had an earthquake simulator consisting of a small platform on which a visitor would stand.
"They reproduced the shaking of the 1964 Anchorage earthquake," he said. "It was pretty strong, and I have to say, I'm not sure their health and safety people would allow such a big earthquake with this demo now."
"Nine-year-old me was very excited about earthquakes after that," he said.
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Gareth obtained his bachelor's and master in science degrees in geological sciences from the University of Cambridge in 1999. A year later he had earned a master's in geophysics from Durham University.
He obtained his PhD in Earth sciences from the University of Oxford in 2005. His research there combined seismology and InSAR.
Then came a seismic life move.
He received a postdoctoral job offer to work 5,295 miles from Oxford at the University of California, Berkeley, to work with his postdoc adviser, Roland Bürgmann, who was establishing himself as one of the world experts in using InSAR data to study active tectonic phenomena such as earthquakes, fault loading, fault creep and postseismic deformation.
Gareth worked as a postdoc from 2005 to 2007 studying fault creep, a subject that remains as his scientific focus.
"This is a weird behavior that certain faults have in a few places on Earth, and California is one,” he said. "It's a very small proportion of the faults that do this."
"It's a special frictional condition that allows the fault to move without suddenly moving catastrophically," he said. “Only part of the fault does it, so you can see where the fault is moving, but you can also see where the fault is not moving. And those areas where the fault is not moving are where you still worry.”
From there he moved on south to the University of California, Riverside, where he started as an assistant professor and then became associate professor. He became a full professor in 2021 in the Department of Earth and Planetary Sciences.
Gareth continues to use InSAR for his research, particularly with his study of fault creep.
There’s a big difference, though, between the amount of Sentinel-1 satellite data needed to study a quick ground displacement by a large quake and the amount needed to study slow and steady creep.
"You need thousands of interferograms to study something that's moving slowly," he said, "whereas you can study a big earthquake with potentially a handful of interferograms."
Needing so much data, however, means contending with the unwanted noise that comes with it.
"One way of capturing a slow-moving thing is you stack up lots of data," Gareth said. "We use a time series approach where the movement of the fault is steady over time and all the other things that you measure are not. If you add up enough data, then you can isolate the thing you want to see, and the noise basically goes away or at least gets suppressed compared to the signal you’re looking for," he said. "Sometimes you make hundreds of interferograms to do this."
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Earthquake InSAR images are works of art, with their reds, yellows, blues, greens and other shades indicating post-quake terrain changes.
Art also has a place in Gareth’s non-work life, showing up as a lover of music. He has an extensive collection of vinyl and also enjoys live music.
He earned money for grad school by DJing at parties. He favors indie music but is, as he puts it, “broadly interested.”
There comes a time, though, when music takes a back seat to an earthquake. It did that on July 5, 2019, when a magnitude 7.1 earthquake struck 140 miles north of the Hollywood Bowl, where he and his wife, entomologist Jennifer Henke, were enjoying a Leon Bridges concert.
“I don’t think the performers noticed; they didn’t stop anyway,” Gareth said. “And I stayed in my seat, but 80% of my attention was on my phone from that point on.”
That quake was located 140 miles to the north in Ridgecrest and was the third and strongest of three quakes at the site over two days. He and colleagues had rushed to Ridgecrest shortly after that first quake to set up five GPS receivers to record any ongoing movement of the ground in response to the earthquake.
The previous day’s earthquake had also proved disruptive to Gareth and Jen. They were at home getting ready for a Fourth of July brunch when it occurred.
“My wife just turned to me and said ‘I’m not getting my burger today am I?’”
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Gareth has served since 2021 on the board of directors of UNAVCO, a non-profit university-led consortium that facilitates geophysics research and education.
UNAVCO merged with IRIS, a consortium of over 100 U.S. universities, to form the EarthScope Consortium in 2023.
He has been a member of the Southern California Earthquake Center’s Science Planning Committee since 2015 and was chairman of the executive committee of the Western North America Interferometric Synthetic Aperture Radar Consortium, WInSAR, in 2017-2018.
Gareth has given numerous invited talks since 2005 and has been the recipient of a NASA New Investigator Award and a Lindemann Postdoctoral Fellowship.
He has served on the advisory board of the Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics and on the Geodesy Section Committee of the American Geophysical Union.
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Gareth has high praise for NASA’s Alaska Satellite Facility Distributed Active Archive Center (ASF DAAC) and what its people have accomplished over the years.
He teaches an InSAR training course through the EarthScope Consortium with Franz Meyer, the Alaska Satellite Facility chief scientist. The two are working with EarthScope staff now to create the 2023 course and will again use ASF DAAC’s OpenSARLab.
“OpenSARLab is amazing and based out of cloud computers,” he said.
Open-access tools like those of ASF DAAC have transformed SAR-based research.
“Having open data is enormous for the growth of InSAR,” Gareth said. “Facilities like ASF DAAC, with their directive to share data with everyone, has really helped democratize science to make sure it’s not just the preserve of a few people,” he said.
“Now I get contacted by people and in all sorts of places who are working on data,” he said. “I had a fruitful series of interactions with a student in Venezuela who was trying to study the faults in her area.”
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