Ammonite Fossil Site

• General Information
• Directions to Red Bluff
• Directions to Black Rock Campground
• Directions to the Fossil Site
• Finding Ammonites and Giant Clams
• Tools and Equipment Required
• Rules and Regulations
• Further Reading

This spectacular fossil area is located in a beautiful canyon in the heart of the Lassen National Forest in the Tehama County of Northern California.

Over millions of years, a creek named Mill Creek had cut deep into the Sierras exposing Late Cretaceous strata (approx. 80 to 90 million years ago). A few million years after that time, an extraterrestrial body hit the earth causing the extinction of the dinosaurs and the ammonites.

From an ecological point of view, this strata witnessed the evolutionary "last stand" of survival made by the ammonites in a sea already conquered by bigger predators. Close relatives of the ammonites, the rare Nautilus and the Argonaut still exist today.

The last town you will reach before heading to a campground at the side of the Mill Creek is the town of Red Bluff, which is located along Interstate 5.

The town has all the creature comforts you will need before heading up the mountains for a real camping adventure. Sport Utility car rentals are available there.

Red Bluff is located approx. 30 miles south of Redding and approx100 miles North of Sacramento.

From Red Bluff take Highway 36 North for 25 miles until the locality of Paynes Creek.

There you take Plum Creek Rd. for 9 miles until you see a sign that reads: 'Ponderosa Way to Black Rock'. Take it.

Ponderosa Way is a very drivable dirt road that goes up the mountains crossing several creeks. The road provides really spectacular scenery. Drive for 19 miles until you reach the bottom of a deep canyon. That is the Mill Creek and the Black Rock campground.

Once you have reached the Black Rock campground and you have settled down, you will need to hike for approx. 1 mile. The trail head is at the western end of the campground.

The trail is easy and goes for up to 6.5 miles. After approx. 0.5 miles of hiking at the side of a private farm, you will see an eroded sedimentary cliff at your left. Soon after, you will go through an iron gate. Cross 4 gullies. Walk for approx. 300 yards, and head straight down the creek.

You will reach a beach with a prominent big purple rock in the middle. This beach is the most convenient collecting site.

Once you are in the creek beach, you will see several hard rocks with fossil shell fragments laying on the floor.

You will also see big boulders of a softer chalk type gray-green sediment material that has fallen from the big cliff up river though natural erosion. This material is easy to break with the hammer. You can find extinct clams (figure), beautiful ammonites and other mollusks

Occasionally, you will encounter smooth and foot long round dark brown rocks buried inside the sediment material. If you split this rocks open you may find giant fossil clams.

• Camping equipment and supplies
• Back-pack
• Geological hammer
• Chisel
• Goggles (important for chiseling hard rocks)
• Gloves
• Video and/or photo camera (some fossils may be to heavy to carry)

This region is called the "Ishi Wilderness" and is within the Lassen National Forest. Permits are not required for the casual fossil collector. If you plan to collect inside the private farm boundary you must ask for the landlord permission first. Also for your safety, you must read carefully the Black Rock's hiking precautions regarding the presence of wildlife displayed at the trailhead.

You must respect the area. Do not dig indiscriminately. You must clean-up and carry all the garbage with you. Please be aware that this fossil site is a gift from nature for everyone to enjoy.

If you think you found an unusual fossil, please contact your nearest museum of Natural History. If you discover a new species, it will be named after you!

The following book is recommended for further reading: 

• "On Methuselah's Trail" by Peter Douglas Ward, W.H. Freeman and Company, New York, 1991. A very educative and fun book to read. It has a section that describes an ammonite collecting adventure from this fossil site region. (Click on book title to link to Amazon.com)

( Nautilus and Argonaut images from "Octopus and Squid" by J. Hunt, Monterey Bay Aquarium, 1996 )