Exploring the Pacific coastline helps students decode Earth’s deep history

Fog drifts over the cliffs as Stanford students make their way down a bluff toward the beach at Shark Fin Cove north of Santa Cruz. From their vantage point, they can see south to Monterey Bay, where kelp and rocks speckle a blanket of blue water. Beneath the surface lies a canyon so immense that “if Monterey Bay were drained, it would look like the Grand Canyon,” their instructor tells them.

Monterey Bay serves as the culmination of the students’ trip. Together, the class learns to decipher clues that connect ancient submarine canyons preserved in the cliffs to the modern canyon hidden beneath the waves. For many, it’s their first time standing at the edge of the Pacific, an experience that never gets old for Steve Cole Dobbs, a lecturer in the Stanford Doerr School of Sustainability.

“Some of them are from the Bay Area, and they've never been here,” said Dobbs. “Some students have never seen an ocean before, so this is a great opportunity to see them get excited about geology and the environment.”

The two-day experience is part of EPS 5: Living on the Edge, a one-credit introductory field course offered through the Department of Earth & Planetary Sciences. The trip takes students from San Francisco to Santa Cruz to piece together the history of California’s coastline. Along the way, students learn to observe, question, and appreciate the timescales of geologic change and the human connections to Earth’s processes.

Fault lines and fossil beaches

The adventure begins closer to Stanford, at Crystal Springs Reservoir, which supplies water to more than a million Bay Area residents. There, students learn that the dam that forms the reservoir sits directly atop the San Andreas Fault. “If the San Andreas fault ruptures right there, that is a huge hazard,” Dobbs said. “It turns out that dam was made before we knew the San Andreas was there.”

The group then travels northwest to an old limestone quarry in Pacifica, exploring the rocks that shaped Bay Area construction. Continuing along the coast, they observe the relentless power of erosion at bluffs where cliffs give way beneath apartment buildings, a dramatic prelude to their next stop: Devil’s Slide.

Once a notoriously treacherous stretch of Highway 1, Devil’s Slide – now a walking trail – reveals the forces that continually reshape the coastline. Here, students examine the mechanics of natural hazards, particularly landslides. “These stops get them thinking about the realities at the intersection of humans and Earth science,” Dobbs said.

For many students, the sites make the science tangible. “At Devil’s Slide, it was very cool to see the impact of geology on people’s lives,” said Maicy Lee-Jones, a first-year student. “We got to learn why landslides happen and how they’ve forced people to move buildings and even entire roads. I never would have thought to go there if it wasn’t for this class.”

Learning to think in deep time

Beyond observing contemporary hazards, Dobbs emphasizes the importance of fostering a deeper understanding of the planet – a new way of seeing. “Humans have been around for maybe 0.006% of Earth’s history, just a blink of an eye. I want them to start thinking in millions of years and see how the planet changes on those scales,” he said.

At San Gregorio State Beach, students examine volcanic ash layers in the cliffs that date back millions of years. At the next stop, Año Nuevo State Park, they walk among fossil-rich sandstone and marine terraces, remnants of ancient beaches lifted hundreds of feet by tectonic activity. 

“Visiting the beaches, studying different rock types, and seeing fault lines firsthand made me see nature from a new perspective,” Lee-Jones said.

Parts of the course, including the visit to Año Nuevo, were redesigned in 2024 through the Stanford Doerr School of Sustainability VPUE/CTL Curriculum Transformation Project on Inclusivity in Field Education. By incorporating activities like sketching the sites, sharing observations, and forming group hypotheses about geological events, the course promotes more interaction and collaboration.

Beyond the rocks

Throughout the weekend, students fill their field packets with landscape sketches, rock layer names, and other observations. “I try to get them used to looking at something and asking, ‘Why is it like that? Why is that mountain there? Why is the beach here?’” Dobbs said.

Khalil Barem, a political science and international relations student, reflected, “I now look at nature’s weird patterns and shapes and lines and ask myself, what is the bigger picture here?”

Beyond the connections they form with the Earth, students also get the chance to immerse themselves in the outdoors alongside peers from a wide range of backgrounds and academic interests.

“It's not every day that you go on a trip with a bunch of students you don't know,” Barem said. “We create close friendships that will hopefully last the rest of our Stanford time and maybe even beyond that.”

Many are still in the early stages of deciding what to study, making the course an opportunity to explore new ideas and possibilities. “It was just a great chance to bond and get a better idea of the different pathways I wouldn’t have looked into otherwise,” said Isabella Dang, a human biology student from San Diego.

By the time the group reaches Shark Fin Cove, they’ve traversed millions of years of Earth’s history. “Then we go to the vista point at the last stop and we say, this is what California looks like now,” Dobbs said. “Students realize the story never really stops.”