Photograph of a trilobite fossil.

Fossils of the United States

What used to live here?

From trilobites to dinosaurs, the United States has an incredibly rich fossil record that tells the story of how ancient animals and plants evolved, lived, and went extinct.

Click on the maps below to find out more about the fossils that have been found near where you live or places that you have visited. These are divided by physiographic province (regions unified by their topography and geologic history). More regions will be added in the near future, so check back again soon!

Map showing the major physiographic regions of the United States.

Major physiographic regions of the United States.

Fossils of the Northeastern United States

Explore the fossil record of New York, Pennsylvania, Maryland, Delaware, NewJersey, Connecticut, Rhode Island, Massachusetts, Vermont, New Hampshire, and Maine.

Photograph of a specimen of the sea scorpion Eurypterus remipes from the Silurian of New York.

Fossil eurypterid (sea scorpion) Eurypterus remipes.

Central Lowland & Inland Basin

Simple map highlighting the Central Lowland and Inland Basin regions of the northeastern United States.

Appalachians & Piedmont

Simple map highlighting the Appalachians and Piedmont region of the northeastern United States.

Coastal Plain

Simple map highlighting the Coastal Plain region of the northeastern United States.

Exotic Terrane

Simple map highlighting the Exotic Terrane region of the northeastern United States.

Fossils of the Southeastern United States

Explore the fossil record of West Virginia, Kentucky, Virginia, Tennessee, North Carolina, South Carolina, Georgia, Alabama, Mississippi, and Florida.

Photograph of the fossil nautiloid Aturia alabamensis.

Internal mold of the nautiloid Aturia alabamensis (Eocene, Florida) on display at the Florida Museum of Natural History (UF 418).

Inland Basin

Simple map that shows the extent of the Inland Basin region of the southeastern United States, which includes all of West Virginia, most of Kentucky and Tennessee, and portions of Virginia, Georgia, Alabama, and Mississippi.

Blue Ridge & Piedmont

Simple map that shows the extent of the Blue Ridge and Piedmont region of the southeastern United States, which includes much of Virginia, North Carolina, and South Carolina, and portions of Georgia and Alabama.

Coastal Plain

Simple map showing the Coastal Plain region of the South Central United States, including all of Louisiana, and portions of Texas, Oklahoma, Arkansas, and Missouri.

Fossils of the Midwestern United States

Explore the fossil record of Illinois, Indiana, Iowa, Michigan, Minnesota, Ohio, and Wisconsin.

Photograph of a large trilobite from the Ordovician of Ohio. The photo shows a brown trilobite exposed on the surface of a gray rock. The head of the trilobite is pointed to the right. The overall shape of the trilobite is roughly oval. The cephalon has two long spines extending backwards. The eyes are relatively small. 

A large trilobite (Isotelus maximus), Ordovician Waynesville Formation, Adams County, Ohio. Photo by James St. John (flickr, Creative Commons 2.0 Generic license, image cropped, resized, rotated).

Central Lowland

Simple map showing the Central Lowland region of the midwestern United States.

Inland Basin

Simple map showing the Inland Basin region of the midwestern United States.

Superior Upland

Simple map showing the Superior Upland region of the midwestern United States.

Fossils of the South-Central United States

Explore the fossil record of Kansas, Missouri, Oklahoma, Arkansas, Louisiana, and Texas.

Photograph of a short-necked plesiosaur skeleton on display at the Sternberg Museum, Kansas.

The short-necked plesiosaur Dolichorhynchops osborni from the Cretaceous Smoky Hill Chalk of Logan County, Kansas. Specimen on display at the Sternberg Museum of Natural History, Ft. Hays, Kansas.

Coastal Plain

Simple map showing the Coastal Plain region of the South Central United States, including all of Louisiana, and portions of Texas, Oklahoma, Arkansas, and Missouri.

Great Plains

Simple map showing the Great Plains region of the South Central United States, including portions of Texas, Oklahoma, and Kansas.

Basin and Range

Simple map showing the Basin and Range region of the South Central United States, including a small portion of western Texas.

Central Lowland and Interior Highlands

Simple map showing the Central Lowland and Interior Highlands regions, which include nearly all of Missouri and Oklahoma, and portions of Kansas, Arkansas, and Texas.

Fossils of the Northwest-Central United States

Explore the fossil record of Idaho, Montana, Nebraska, North Dakota, South Dakota, and Wyoming.

Photograph of a mounted Tyrannosaurus rex specimen called "Montana's T. rex" on display at the Museum of the Rockies in Bozeman, Montana. Tyrannosaurus is a carnivorous dinosaur with a large skull and large, slightly curved, pointed teeth; it is bipedal, with powerful hind legs and relatively puny arms. The tail is long and held up off the ground. The photo is taken from the rear-side of the skeleton, showing much of its length, with the tail especially prominent. The end of the tail and the feet are cropped out of the image. The skeleton is mounted in a striding position.

Montana'sT. rex on display at the Museum of the Rockies in Bozeman, Montana. Photo by Tim Evanson (flickr, Creative Commons Attribution-ShareAlike 2.0 Generic license, image cropped and resized).

Central Lowland

Simple map showing the Central Lowlands region of the northwest-central United States.

Great Plains

Simple map showing the Great Plains region of the northwest-central United States.

Rocky Mountains

Simple map showing the Rocky Mountain region of the northwest-central United States.

Columbia Plateau

Simple map showing the Columbia Plateau region of the northwest-central United States, which occurs entirely within Idaho.

Basin and Range

Simple map showing the Basin and Range region of the northwest-central United States, which occurs entirely within Idaho.

Fossils of the Southwestern United States

Explore the fossil record of Colorado, New Mexico, Arizona, and Utah.

Photograph of a juvenile sauropod skeleton in a death pose partially embedded in rock. The sauropod has a long neck, a small head and is quadrapedal (walks on all fours). The tail is arched upward.

Skeleton of a juvenile Camarosaurs lentus, a type of sauropod, from the Carnegie Quarry, Jurassic Morrison Formation, Dinosaur National Monument, Utah and Colorado. Photo by James St. John (flickr, Creative Commons Attribution 2.0 Generic license, image cropped and resized).

Colorado Plateau

Simple map showing the area of the Colorado Plateau province of the southwestern United States.

Basin and Range

Simple map showing the area of the Basin and Range province of the southwestern United States.

Rocky Mountains

Simple map showing the area of the Rocky Mountains province of the southwestern United States.

Great Plains

Simple map showing the area of the Great Plains province of the southwestern United States.

Fossils of the Western United States, including Hawaiʻi

Explore the fossil record of California, Nevada, Oregon, Washington, Alaska, and Hawaiʻi.

Photograph of the rear end of the trilobite Nevadia parvoconica from the Cambrian of Nevada. The sides of the animal has a series of spines that curve backward. The spines are orange in color and stand out from the gray rock matrix.

A trilobite (Nevadia parvoconica), Indian Springs Lagerstätte, Early Cambrian Poleta Formation, Esmeralda County, Nevada. Photo by Paleontological Research Institution (PRI) on GBIF.org (CC0 1.0 Universal/Public Domain Dedication).

Basin and Range

Simple map of the Basin and Range region of the western U.S.

Columbia Plateau

Simple map showing the location of the Columbia Plateau physiographic region of the western United States.

Rocky Mountains

Simple map showing the location of the Rocky Mountain physiographic region of the western United States.

Cascade-Sierra Mts. 

Simple map showing the location of the Cascade-Sierra Mountains physiographic region of the western United States.

Pacific Border

Simple map showing the location of the Pacific Border physiographic region of the western United States.

Alaska

Simple map of Alaska.

Hawaii

Simple map of Hawaii.