The Hills Are Alive--With Fragments of Past

Strange as it seems, you don’t have to go to the beach to find shells, sand dollars and other marine treasures.

The hills are loaded with them. Miles from water, these fossils are remnants of a time millions of years ago when the San Fernando Valley, Ventura County and much of Southern California was underwater.

But don’t think you can head for hills and stumble across a 50-million-year-old starfish. It’s not that easy. Help, however, is all around for anyone wanting to learn more about fossil hunting.

Rock clubs in the Valley and Ventura County sometimes take field trips to fossil-rich spots. There are classes for adults and children that plunk them down in the dirt of the Santa Monica Mountains in search of ancient sea shells.

This weekend there is even a guided hike for those interested in learning something about the geology of these mountains. And, of course, museums are nearby in Los Angeles.

For beginners, it’s wise to hook up with experienced rock hounds like those you’ll find in rock clubs in Canoga Park, Reseda and Thousand Oaks. Although not all members are into fossils, some have an amazing amount of local lore to share.

“If you don’t know where you’re going and what you’re looking for, you won’t have very good success,” said Cheryl Council, president of the Conejo Gem & Mineral Club in Thousand Oaks. Even if you find something, it will take an experienced eye to identify it and offer advice on cleaning it.

Her club, which includes about 60 or 70 families, is trying to infuse its ranks with younger members. Its youth group has attracted a couple dozen rock hounds, and among them are Council’s two teenagers who have been at it for six years.

“You find your first one and you kind of get hooked,” she said.

Before grabbing a hammer and chisel, the novice needs to learn the basics. The rules about collecting on public land are confusing: some agencies prohibit it while others allow some casual collecting of certain types. On private land, the owner’s permission is needed. Some good spots are just obscure road cuts or washes; for most, a map is necessary.

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And forget dinosaur fossils. It’s highly unlikely any of these will be found around here. When these guys thrived 200 million to 65 million years ago, Ventura County and the Valley were, for the most part, under the sea. But underwater forces started creating mountain ranges, gradually pushing the area up out of the water. It surfaced, along with much of Southern California, only to be covered again by water, finally emerging as we see it today during the last few million years.

Paleontologist John Alderson covers all this in a two-day class he teaches through Learning Tree University on the Chatsworth Campus. The evening lecture on March 29 is followed by a four-hour outing March 30 in Topanga Canyon.

Narrow, winding Old Topanga Canyon Road is one of the most popular spots around. Although property ownership is unclear, the road-cuts along here have attracted fossil hunters since the turn of the century. On weekends, cars pull over and families rummage through the rocky debris that has slid down the sandstone cliff next to the road. Turritella shells, shaped like a corkscrew, are easy pickings here.

According to Alderson, the area is rich with marine fossils--more than 100 species including clams, snails, crabs, sand dollars, shark teeth, fish scales and whale bone, estimated to be 16 million to 17 million years old.

During the outing he leads, he explains how the fossils end up in the sedimentary rock layers. The area, probably a shallow-water bay at one time, was under water until 2 million or 3 million years ago.

The Agoura Hills-based Wilderness Institute leads fossil hunting outings in Topanga Canyon, and Alderson will direct one for adults in June. On March 30 and May 25 naturalist John Hughes will do two-hour digs with kids, explaining the geology of the area and helping to identify finds.

“Most of the fossils are in the Santa Monica Mountains--it’s full of fossils, there are places by the side of the road,” said Alderson, who also leads groups on geology and paleontology trips throughout Southern California.

Experienced fossil hunters will say that the best time to look is after a rain. Water erodes the dirt in canyons, washes and road-cuts, where fossils might be nestled just below the surface.

Those heading for the Santa Monica Mountains must be aware that collecting is prohibited on state and national parkland. But learning is always encouraged, and those interested in knowing more about the fossils and the geologic upheaval that put them here should know about the two outings scheduled this Saturday in the mountains.

At Point Mugu State Park, geologist George Roberts will lead a hike into La Jolla Canyon, identifying rock formations along the way. The other is a jaunt with geologist Greg Sweel into Malibu Creek State Park, where the nature center there has fossilized fish on display.

Another fossil-rich protected area is Fossil Ridge Park in Sherman Oaks. Located off Mulholland Drive, this 109-acre parcel wedged against a posh housing development contains fish fossils more than 10 million years old. Managed by the Santa Monica Mountains Conservancy, it opened about six months ago and features a quarter-mile trail on the top of the ridge.

The tiny fossils are in bits of rock on the ground that take a skilled eye to recognize. Disturbing the rock is prohibited here. It’s tricky getting in, too; visitors must sign in at the guard station by the entrance to the subdivision.

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It wasn’t far from this ridge seven years ago that Alderson said he located a “mass graveyard of perfect whole fish.” They were herring, three to five inches long. He had been driving by a site that was being excavated for future development.

“I recognized the layers (of rock),” he said. “I started poking around.” Eventually a team from the Los Angeles County Museum of Natural History pulled out over 200 of the fish.

The hills around Chatsworth have yielded shells 70 million to 80 million years old, he said. In fact, marine fossils are the easiest for amateurs to find. But paleontologists have unearthed aquatic vertebrates and land mammals too, especially in the Simi Valley area.

These include crocodiles, saber-toothed cats, rhinoceroses, camels, horses--some 40 million years old. Prehistoric horse teeth have been found in Camarillo.

Maxine Dearborn, a member of the Reseda-based Del-Aires Rock Hound Club, said many of the good spots in the Valley have been covered up by development, so she often heads for Ventura County. But the same thing is beginning to happen in Simi Valley, a popular area for fossils.

“It’s sad,” she said, “but those rocks will be there long after the houses are gone.”

Anyone willing to drive a bit will find that Ventura County has other fossil possibilities. Bruno Benson, 81, has been tracking down fossils there since 1929. One of his prized possessions is a hunk of rock containing 23 tiny, delicate starfish 60 million years old from a spot north of Ojai in Los Padres National Forest.

In the Pine Mountain area of Los Padres, fossil hunters have located ancient sand dollars. Casual collecting of invertebrate fossils such as shells are permitted in the national forest without a permit.

Beaches are another source for rock hounds looking for ancient shells, petrified whale bone or coquina agate, those grayish black stones with white fossil shells embedded in them. But rules vary at different locations, so check with a ranger before collecting.

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DETAILS: CLUBS

* CONEJO GEM & MINERAL CLUB, meets second Thursday of the month, 7:30 p.m., Arts Council Cultural Center, 482 Greenmeadow Drive, Thousand Oaks; (805) 498-4220.

* WOODLAND HILLS ROCK CHIPPERS, meets third Saturday of the month, 7:30 p.m., Canoga Park Community Center, 7248 Owensmouth Ave., Canoga Park; (818) 347-2056.

* DEL-AIRES ROCK HOUND CLUB, meets third Monday of the month, 7:30 p.m., Reseda Park Recreation Building, 18411 Victory Blvd., Reseda; (818) 347-2056.

OUTINGS

* MALIBU CREEK STATE PARK, Saturday, 10 a.m., two-hour easy-paced walk with a geologist to learn about area rock formations. Sponsored by Malibu Creek Docents. Meet at lower parking lot; no reservations required. No fee for walk, but $5 fee for parking.

* POINT MUGU STATE PARK, Saturday, 10 a.m., four-hour hike into La Jolla Canyon with a geologist to learn about geologic history. Sponsored by California Department of Parks and Recreation. Bring lunch and water. Meet at Ray Miller Trailhead at La Jolla Canyon. No reservations required. No fee for walk, but $6 parking fee.

* FOSSIL HUNTING for kids 8 to 12 years old, March 30, 9 to 11 a.m. Sponsored by the Wilderness Institute. Cost is $15; parents can participate. Reservations required; call (818) 991-7327. Map to site in Topanga Canyon will be provided.

* LEARNING TREE University, Chatsworth Campus, offers a class called “Digging up Fossils,” March 29 and 30. Taught by paleontologist John Alderson, it includes an evening lecture and four-hour dig in Topanga Canyon. Cost, $39. For information and reservations, (818) 882-5599.