What Lies Beneath? A Q&A with LSU Seismologist Patricia Persaud
Seismologist Patricia Persaud is one the latest additions to the faculty community in the LSU College of Science. A native of Guyana, Patricia has always been curious about natural occurrences and how these events impact our world. She began her undergraduate career at the University of Houston as a physics major, but decided that she wanted to apply physics in a less traditional way. She was drawn to the geosciences and the challenge of uncertainty that comes with studying the Earth.
Patricia earned a bachelor’s from the University of Houston and a Ph.D. from the California Institute of Technology. She joined the faculty in the LSU Department of Geology & Geophysics this fall. Let’s learn a bit more about Patricia and her exciting work uncovering the mysteries that lie beneath the Earth’s surface.
LSU College of Science: What was your earliest experience with Geophysics?
Patricia: As a child living in a low-lying coastal area close to the equator, I couldn’t understand why hurricanes would hit the Caribbean islands to the north but never us. Why could you feel the shaking from earthquakes that were so far away? Why are some high tides higher than others? My father encouraged me to measure the tides. My geophysics experience started with observations of natural phenomena where I lived.
LSU College of Science: Tell us a bit about your research. What drew you to this research focus?
Patricia: The surface of the Earth is made up of many pieces called plates that fit together like a puzzle. The plates are constantly moving though very slowly, maybe just a couple of centimeters each year. Over geologic time this slow and constant motion adds up; mountains grow and ocean basins form and almost all of the action is occurring at the edge of plates, including earthquakes and volcanoes. Coincidentally, that’s where humans like to live too.
I am interested in understanding plate boundaries, such as the one in the Eastern Mediterranean offshore of southern Italy and the one in Southern California. These are sites where elusive earth processes have a huge impact on humans. As a seismologist, I study earthquakes and associated phenomena, or you could say I study changes in seismic waves as they pass through the Earth. Seismology is the primary tool for investigating the earth’s interior because most of our planet is not accessible to direct observation. Being able to measure small changes in seismic waves gives us a remarkably sharp picture of what’s beneath the Earth’s surface.
I was drawn to this field as an undergraduate. I was fortunate to be able to work on the seismic data from the Chicxulub impact crater, the one associated with the extinction of the dinosaurs. This amazing feature is completely buried, but you can see it very clearly in the seismic data.
LSU College of Science: What do you get most excited about in talking about your research to audiences who are not scientists?
Patricia: If after I explain my research to someone, they do NOT ask me when is the next big earthquake; this means I have gotten through to them.
LSU College of Science: What inspires you or keeps you motivated to pursue your research? What are the biggest day-to-day challenges in your field of research?
Patricia: I am most inspired by my students. Having a beginner’s mindset allows you to think of old problems in new ways.
The biggest challenge in my field is collecting data. Seismometers, the devices we use to “listen” to the Earth, are expensive, and many are needed to create clear images of what’s beneath the surface. This means we need to be highly selective about our target areas.
LSU College of Science: What are the biggest unanswered questions in your field of science/research?
Patricia: “When is the next big earthquake?” Earthquakes are almost random processes, and we continue to learn new things about those processes. Recently, some researchers have shown that big tides can trigger large earthquakes.
LSU College of Science: What are you most proud of in your career so far?
Patricia: If based on the biggest societal contribution I have made, that would be my recent research published in Geology. In that study, we installed seismometers (instruments that measure the motion of the ground) at 4,125 locations in southeastern California and Mexico as part of the 2011 Salton Seismic Imaging Project, a collaborative project between U.S. and Mexican institutions. Using the recordings from 126 underground explosions, we produced an image of the Earth much like a CAT scan images the human body. We were able to identify buried interfaces or faults and produce a “seismic” scan to show what’s beneath the Earth’s surface. This will help refine the seismic hazard for parts of Imperial County, California, where the population is projected to almost double by 2060.
LSU College of Science: What was your first impression of LSU?
Patricia: LSU is big. I still haven’t gotten over that.
LSU College of Science: What excites you most about being at LSU?
Patricia: That it is a diverse environment. I love being able to interact with other faculty and research groups doing such different things.
LSU College of Science: Louisiana is known for its food and eclectic culture. What have you enjoyed most about being in Louisiana?
Patricia: I love the creole food and culture and the rain, just not too much of it. I probably moved from one of the driest places in the U.S., Southern California, to one of the wettest places.
LSU College of Science: What courses will you be teaching?
Patricia: I will be teaching Introduction to Seismology for seniors and graduate students in Spring 2017.
LSU College of Science: What is your approach to teaching and what can students expect from your class(es)?
Patricia: I have a very interactive classroom. Students are active and learn by doing. Seismology is not magic, and it has lots of applications, e.g., identifying nuclear explosions, monitoring landslides, so my goal is to take the mystery out of it.
LSU College of Science: Outside of your academic life, what else do you do to keep yourself busy? Do you have any hobbies?
Patricia: Outside of academic life, I try to slow things down a bit. I have a regular yoga practice that keeps me grounded. Once in a while I do something scary like caving or mountain-climbing.
LSU College of Science: Are you on social media? Where can we keep up with you?
Patricia: I keep it simple since most of my time is spent on the computer, so my “social media” is having a good cup of coffee with a colleague or face-to-face time with students.
Persaud is one of 16 College of Science researchers presenting at the fall 2016 meeting of the American Geophysical Union, December 12 – 16, in San Francisco, CA. Her talk, Active Tectonics of the Imperial Valley, Southern California: Fault Damage Zones, Complex Basins and Buried Faults, will provide valuable insight to our understanding of the seismic hazards present in parts of Imperial County, CA.
You can view select research presentations through the AGU On-Demand program including an LSU press conference entitled Water World: Historic Floods, Sea Level Rise, Storm Surge and Climate Change featuring Scott Hagen.
Here's a list of the AGU presentations available on demand.