Romancing The Stone: A Geology Walk

Paleontologist and geologist Frank Perry leads a unique field trip along the San Lorenzo River on Sept. 19 as part of the Watershed Walks series sponsored by the San Lorenzo Valley Water District.

by Carol Carson

Sept. 15, 2015—Sometimes a stone is just a stone, caching itself in the side of a cliff or scuttling out to sea as a winter storm scours the river bottom.

Sometimes it is a secret treasure. Cracked open, the contents might reveal a little gem, a fossil no human being has ever seen.

Popular paleontologist-geologist Frank Perry will lead a unique field trip along the sandbars of the San Lorenzo River on Saturday, September 19, from 10:30am till 12:30pm. Sponsored by a grant from the San Lorenzo Valley Water District, the walk is free, but parking in the Henry Cowell Redwoods State Park in Felton costs $10.

First Perry will exhibit maps that identify local faults, landslides and flood plains, as well as sharks’ teeth found in Scotts Valley, sand dollars from Bean Creek and a mammoth’s tooth from Año Nuevo.

His well-received exhibit, “Bones: An Inside Look at Nature,” at the Santa Cruz Museum of Natural History, introduced a 5-million-year-old whale that was discovered by a man walking on a Santa Cruz beach. A fossil from the Pliocene epoch, the whale’s teeth confirm that it was a meat-eater, related to the modern-day orca and dolphin.

How did the man find the whale? “He had educated himself and trained his eyes to see things. An untrained eye can walk right by it and not see it,” Perry explained.

At the geologist’s last walk, our citizen scientists ambled down to the banks and began happily hammering away at very ordinary looking stones. Suddenly, Eureka! The amateur rock hounds were jumping up and down and encircling Perry three-deep, showing him their exhumations. “What’s this, Frank?” “What’s this?”

“That’s a fossil clam,” he answered, “and that’s a leaf imprint.” Ancient tumbled rocks were no longer “ordinary.” No matter what the age, we were kids in a candy store.

After we had mined our quarry, we packed up our booty and headed south on the river walk following the luminous San Lorenzo River. At the convergence of Eagle Creek and the river, Perry pointed out where the sedimentary rock collides with formations of igneous rock found in mountain cores.

GEOLOGY WALK WITH FRANK PERRY is Saturday, Sept. 19, 10:30am-12:30pm, at Henry Cowell State Park on Hwy 9 in Felton. The walk is free, but the price to park per vehicle is $10, $9 for seniors, or you can park outside on Hwy 9 on the shoulders and walk in. As soon as you pay at the kiosk, turn right into the picnic area and go all the way down to the end and park at Lot 3 by the restrooms on the left.

The walk is open to all ages, but space is very limited. To register and receive more information, please contact Carol Carson, Certified California State Naturalist, at
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