Alumna Gift Advances Innovations in Fiber-Optic Seismology Research
Caltech alumna Dayna Salter (BS '76) has donated $300,000 to support Professor Zhongwen Zhan's (PhD '13) groundbreaking seismology research using fiber-optic cables.
Zhan's research focuses on converting fiber-optic cables into extensive networks of seismic sensors. This innovative approach, known as distributed acoustic sensing (DAS), transforms every meter of fiber-optic cable into a sensor capable of detecting seismic waves.
"The beauty of Zhongwen's research is that he is using existing permanent fiber-optic cable networks laid out for entirely different purposes," says Salter, a retired geophysicist. "He has developed the technology to use them to monitor Earth constantly and on a fine scale."
Salter's gift is particularly valuable, Zhan says, because it supports high-risk, high-reward research projects that might not receive funding from traditional sources.
"Federal funding often requires preliminary results to demonstrate the feasibility of a project," Zhan notes. "Private donations like this allow us to pursue innovative and exploratory research that can lead to significant breakthroughs. Dayna's support enables us to push the boundaries of what is possible and explore new frontiers in seismology."
Enabling High-Risk, High-Reward Research
Traditional seismology relies on discrete sensors placed at intervals, but DAS allows for continuous monitoring along the entire length of the cable. This provides a much more detailed and comprehensive picture of seismic activity.
"This technology can significantly enhance our ability to monitor earthquakes and other seismic events," Zhan explains. "It allows us to detect and analyze seismic waves with unprecedented precision, which is crucial for understanding Earth's internal processes."
Zhan's team has already started using the funds from Salter to deploy fiber-optic cables in remote and challenging environments. One such project involved installing cables on a glacier in Iceland to study ice dynamics. The data collected from this experiment will help researchers understand how glaciers melt and move, which has direct implications for evaluating the impacts of climate on global sea-level rise.
"The data we collect will not only enhance our knowledge of seismology but also contribute to broader scientific understanding of how ice is responding to climate change," Zhan says.
A Shared Passion for Geophysics
Salter's geophysics background and her understanding of the challenges and opportunities in the field played a significant role in her decision to support Zhan's research.
"As a geophysicist in the oil industry, I interpreted seismic data from man-made sources and sensor cables to find oil and gas prospects," Salter explains. "As a seismologist at UC Berkeley, we relied on a global network of seismometers to record earthquakes and used that data to study our zones of interest, but those seismometers were few and far between for deep earth research, and the need for appropriately sized earthquakes limited our observations."
Salter's interest in geophysics began at Caltech. As an undergraduate, Salter was initially drawn to space and planetary exploration. "I was interested in being an astronaut. I wanted to go to the moon. I wanted to go to Mars," Salter recalls.
But when NASA's Apollo program began winding down in the middle of her freshman year, Salter's focus shifted to Earth, and she found herself particularly interested in earthquakes and seismology.
After earning her degree at Caltech, Salter pursued a Master's in Geophysics at the University of California, Berkeley, focusing on deep mantle structure. She then transitioned to the oil industry, starting as a geophysicist with Chevron and later moving to Mobil and ExxonMobil. Throughout her 35-year career, she specialized in production geophysics, collaborating with multidisciplinary teams to drill and evaluate production wells in challenging environments like offshore in the Gulf of Mexico and Chad. Salter retired in 2015.
In 2021, Salter returned to Caltech as a member of the Division of Geological and Planetary Sciences (GPS) Chair's Council. "I was looking for ways to give back to Caltech, since it had opened so many doors for me, and I highly enjoy the reviews of current research to which we are exposed," she says.
It was during one such research presentation that Salter first learned about Zhan's work using existing fiber-optic cables to monitor seismic activity. "I just thought that was very clever," Salter recalls. "When I told him I was interested in sponsoring his research, he told me of a marine project that was still a rough idea and that needed formulating and testing."
Collaborative and Interdisciplinary Environment at Caltech
Salter was pleased to learn upon her return to Caltech that the collegial and collaborative environment she admired so much as an undergraduate was still intact.
"What impresses me is the division's philosophy and the way they approach problems," Salter says. "The commitment to learning and bringing other people along has only improved over the years."
Indeed, Zhan praises the collaborative and interdisciplinary environment at Caltech, and especially the Seismological Laboratory he is a member of, as being a key factor in his team's success. "We have a unique setup here where researchers from different disciplines regularly interact, share ideas, and collaborate on projects," Zhan says.
Zhan has worked with electrical engineers to develop the DAS technology used in his seismic studies and with oceanographers to apply it to marine environments.
"Despite our varied specializations, we naturally work together on complex scientific questions," Zhan says. "We're always seeking new opportunities, which keeps our careers refreshed and allows us to make significant contributions."
Salter encourages her fellow alumni to stay involved with Caltech as much as they can and to consider giving back in a field that interests them. "It has been eye-opening to me, the opportunities that exist," she says, "from innovative research projects too new to be funded formally to postdocs or grad student projects."