|Home - City Guides|
|Oregon Coast Notes|
|12th Annual Oregon Coast Fossil Fest|
Feb 9, 2013
Attend The 13th annual day-long Fossil Fest event on Saturday, February 9 at the Hatfield Marine Science Center in Newport.
This is your chance to have an up-close look at some exciting fossils and the scientists who work with them! Activities will include a fossil swap and special displays staffed by the North American Research Group.
Bring in your fossils or other beach finds for identification by Oregon's preeminent paleontologist, Dr. William Orr. Dr. Orr will be giving a presentation in the Hennings Auditorium at 1:30pm entitled "Digging up the Kings Valley Groundsloth". He will also be available to sign copies of his book, Oregon Fossils. This program is open to the general public, and as always, admission is by suggested donation.
Only 11,000 years ago the Willamette valley had a vertebrate fauna of very large to huge mammals including elephants (Mammoth & Mastodon), Sabre tooth cats, dire wolves, giant beaver, bison, condors and ground sloths. The latter group included two species of which the Harlan sloth (Mylodon harlani) was the most common. The remains of such a sloth were discovered almost a generation ago in Kings valley and excavated only last winter. The skeleton is about 80% complete and Dr. Orr's talk will take you through the process of excavation, stabilization of the bones and identification. Discover that the sloth was related to anteaters and armadillos, had sharp claw-like fingers up to a foot long, was armored with thousands of bone pieces imbedded in its inch thick leathery hide and weighed in at almost 2000 pounds!
Fossils on Oregon Beaches
Oregon's sandy beaches are known for their shells, sand dollars, agates, and jaspers, as well as for a wide variety of Miocene-era marine and mammal-bone fossils.
Geologically speaking, Oregon coast fossils are found in three formations: the Astoria Formation, 15- to 20-million-year-old sandstone layers mixed with compressed volcanic ash; Nye mudstone, up to 20 million years old; and on south coast stretches of beach, Coledo Formation specimens of dark ash and sand, which are 25–30 million years old. These formations of compacted sand, volcanic ash, and river-borne silt are uplifted from the Pacific Ocean floor by geo-plate movement.
Layers of rock and sediment exposed above sandy beaches between basaltic headlands form the larger, more permanent hills along the Oregon coast. The combination of eroding basalt, mud, and sandstone produces a combination of rocks and fossils mixing on the beaches with sand. There are dozens of species of fossilized marine life, ranging from microscopic algae to the hand-size Panopea abrupta and the dinner plate-size Patinopectins and smaller Vertipectins.
A note about seawalls: While Oregon's beaches are public, the seawalls above them where people's homes and public highways are located generally are not. Do not use tools to remove anything from a seawall--this is a violation of Oregon law.
While clams are the larger and more populous of Oregon's Miocene marine fossils, gastropods (for example, snails) are frequently found, especially in concretions. For some, the attraction of gastropods results from the artistic 180° twist the shell makes during its growth, called torsion. Most gastropods--herbivores and carnivores--use an armored tongue, or "radula," as a tool to drill through shells into their meals. Common Miocene gastropods making Oregon's coast their home include...
Wood and Bone Fossils
In addition to abundant marine fossils, Oregon's coast offers a wide variety of petrified woods. As ocean currents moved along the shoreline and rivers ran into the Pacific Ocean, wood species from other regions were deposited on Oregon's beaches.
Teredo wood appears as brown to black rocks, usually rounded at the ends with a "Swiss cheese" look to them. Fossilized casings from the Teredo marine clam created the pattern when the Teredo, in its larval form, ate its way through chunks of ancient wood. These colonies of small larvae never cross each other's borings, making each piece unique in design and appearance. Other petrified woods are light tan to carbonized black, frequently found in sizes ranging from one inch to two feet across. Look for a dull sheen on wet rocks with parallel wood grain patterns. Softwood species of pines and some hardwoods, including alder, myrtlewood, and oak, as well as petrified palm, are also found on Oregon beaches.
An occasional fossilized leaf impression can be found on or in coastal rocks, recognizable as elm, alder, and Oregon Grape--Mahonia repens.
Petrified wood pieces are also often found in concretions of rounded mudstone or hard gray volcanic ashballs. Sometimes split in half by nature, inside these concretions is often carbonized or fossilized wood that was once carried downstream from the Cascade Mountains. Crabs are one type of arthropod found inside concretions when split open--claws, legs, and occasionally whole crabs.
Another genre of fossil found on Oregon's coast is mammal bone. Usually deposited in hardened sandstone, bone is as abundant as Teredo wood and Anadara shells. Look for light brown or gray rocks with rounded edges and a darker edge or center, which is usually bone.
Most fossils can be found at low tide on sandy beaches, in creek washes, and below the rockier headlands in high-tide rock piles. Fossils found on public beaches may be taken, but they may not be commercially sold without a permit. You cannot legally collect or take fossils from marked "marine gardens" or beaches adjacent to Oregon State, U.S. Forest Service, or BLM parks, campgrounds, and natural areas.
You can find a link to the publication, "Fossils You Can Find on Oregon Beaches" at the Hatfield Link below.
Oregon State University's Hatfield Marine Science Center (in Newport) and the Oregon Museum of Science and Industry (in Portland) are two locations where you'll find exhibits of fossils discovered on Oregon's beaches.