Finding Fossils In Baja

By David Kier

Once upon a time, Baja’s desert was underwater! The prehistoric sea location is quite obvious when you see fossilized shells, coral, and sharks teeth. They are found far from the ocean, or hundreds of feet above today’s sea level. A combination of geologic activities has created these fossils sites. Ice ages change the sea level, but the land also has moved higher or tilted up in tectonic upheavals. Baja California was once upon a time nice and snug next to the rest of Mexico. Six million years ago, a huge crack began to split off the future peninsula. About 4 million years ago, the cape region rotated out towards the west and created the Gulf of California. Ancient sea floors would be thrust upwards, and then be covered by mud from floods and lava flows, only to get re-exposed later by erosion. Fossils from a wide range in time are found all over in this geologically diverse land.

Ammonites (giant snail-like shells) are some of the oldest fossils that have been found in abundance, in Baja California. Some ammonites are on display at Mama Espinoza’s Restaurant, in El Rosario. They were found many miles to the south, and several miles from today’s coastline, in the region of Santa Catarina.

Just 3 miles west of El Rosario, is an arroyo littered with petrified wood of various sizes. To visit El Rosario’s Petrified Forest inquire about a guide from one of the town’s motels or restaurants. See more photos at http://vivabaja.com/206

The fossil grotto of Las Pintas is an interesting side trip: Drive 14.6 miles south of El Rosario (from the Pemex station) on Highway One to kilometer marker 80+ and take the wide dirt road right, going towards Punta San Carlos. 17.4 miles from the highway turn left onto a single track road. Zero your trip odometer and head east along the Arroyo San Fernando river valley, passing the abandoned ranch of Malvar. A gate may be closed at 3.5 miles, so do close it behind you to keep cattle in. At 5.2 miles, a faint track turns left into a small side arroyo. At 5.4 miles you turn right and climb out of the small arroyo. You will cross over a low rise and enter another valley. Arrive at Las Pintas at 7.2 miles.

Las Pintas is a fascinating jumble of boulders that create a dramatic waterfall when wet. The boulder are filled with fossils and covered with petroglyps for a multiple Baja experience! A trail climbs around the boulders to the top and there are trails to the hidden waterfall room straight ahead, squeezing between room size boulders. A tougher 4WD road continues up the arroyo back at mile 5.4, and goes 1 mile to another fork, and go right 1.4 miles to the parking area, near the top of Las Pintas. Las Pintas has an endless supply of exploring for fossils and petrogyphs.

On the east side of Baja California we have seen samples of clams, oysters, and sand dollars all petrified, 5 miles from the ocean and 600 feet above sea level. This was in the area south of the sulfur mine, and close to the old Puertecitos road (approx. 25 miles south of San Felipe). Other fossil sites are further inland and near the road from San Felipe to Valle Chico. Layers upon layers of petrified oysters and other clams are found. Bruce Barber wrote a book in 2003 (‘… of Sea and Sand’) that describes many fossil sites and other geology around San Felipe.

In the desert near Bahía Asunción, one finds fossilized coral, sea shells and shark’s teeth spread over a large area of mud hills. Inquire locally for directions or a guide. We spent an afternoon fossil hunting there, on the Vizcaíno Peninsula of Baja California Sur. A combination of the peaceful quietness and making these small discoveries turned it into one of our best vacation days. The sharks’ teeth were shiny compared to the ground they laid upon.

Once you see an area of petrified sea life, you will notice what it has in common with other sites are dry mud hills, of various colors. When you find such a place, start looking and be very slow… the fossil will catch your eye as looking out-of-place, shiny, or darker.

Happy Hunting and remember to take only pictures and leave only footprints… it’s the law, and a good idea for the enjoyment of future Baja explorers!