LAGUNA BEACH >> Mark Garcia and his girlfriend, Yvonne Bellgardt, were looking for sea glass in the rocks near the tide pools north of Main Beach when they came across a more ancient find.
“I looked over and saw these clams,” said Garcia, of Mission Viejo. “Then I realized they were sitting inside rocks in the tide pools. The rocks were filled with lava flows. I figured they have to be pretty old.”
Garcia, 50, a retired police officer and Bellgardt, a photographer, spend most weekends at the beaches in Laguna but that day in November was a first.
Garcia began comparing photos of the fossils to images he found on the internet. His research stirred his curiosity even more, so he contacted several geology professors at Cal State Fullerton.
John Foster, a geological engineering professor, analyzed the photos and told him the fossils appeared to be Miocene-age clams and likely 17 million years old.
“When he told me that, I couldn’t believe it,” Bellgardt said. “It was just amazing.”
On Monday, Jan. 22, Garcia was excited to get actual confirmation about his discovery.
He met Foster and Hugh Wagner, a geologist and paleontologist, at the site beneath Heisler Park. The trio walked along the rocks at sunset and Garcia pointed to his discovery: a cluster of clams, barnacles and snails all within about six feet of rock above the beach near the water’s edge. The site is in Laguna’s Marine Protected Area, a location where items cannot be removed or disturbed.
“This is the Miocene Epoch, a period when the megaladon, an extinct species of a stockier version of a great white, swam in the oceans,” said Wagner, visiting from Goldfield, Nev., as he brushed sand from a clam embedded in rock he classified as the Topanga Formation. “This was the beginning of the whales and primitive sea lions. The megaladons would have been swimming in water above these invertebrates. These clams used to be at the bottom of the ocean. Over time they washed up higher on shore and died.”
A hippo-like creature known as the desmostylian may have been feeding along the shoreline where the clams, snails and barnacles lived, Wagner said.
“This creature would likely have crunched the invertebrates using its cylinder-like tooth from its upper and lower mouth to crush them,” he added. “It would have lived here more than 12 million years ago and would have come over from Asia.”
A desmostylian jawbone was discovered in 1996, near the 241 Toll Road in Mission Viejo.
Wagner examined the fossils and determined that likely some of the clams died quickly because of how tightly the valves were closed. He also established that they were a single community and that many were well-preserved.
He and Foster noted that the rock formation just above where the fossils were found was from a more recent time period and that at some point that rock formation had likely started sliding over where the fossils were located, which explained why the grouping abruptly stopped.
“Geologists will note the location and get a GPS reading and through that get an idea why these fossils are right here and no where else along here,” Foster said. “By putting this on maps, it puts together a history of the area.”
For Garcia, an ocean enthusiast who’s long been on a search for interesting finds, the confirmation by the scientists made his discovery even more special.
“It’s exciting because the average person doesn’t walk across fossils that are 17 million years old,” he said. “To hear how it all began and how it’s exposed now — as a person who loves the ocean, that’s neat to see.”
