When you get to the Grand Canyon and gaze out at the incomprehensibly large sight in front of you, you might not even notice the life right beneath your feet. When you stand on the rim of the canyon, you’re on top of a 270-million-year-old sea floor.
All around Arizona, rocks hold remains of life that lived hundreds of millions of years ago. When people think fossils, dinosaurs typically come to mind – but that’s only one part of the picture.
Fossils of microbes, sea sponges, insects, sharks, early amphibians and mammals have been discovered in the rocks around the state, representing over 1 billion years of life on Earth.
► USA TODAY Travel newsletter: Get the latest headlines in your inbox daily
Where can I find fossils in Arizona?
Fossils are all around you at parks and public land across the state, you just need to know what to look for.
There are 22 park units in Arizona with paleontological resources, according to the National Park Service. Visitor centers at many of these sites contain fossils, but with COVID-19 closures limiting access to indoor spaces, the best places to easily see fossils outdoors are Grand Canyon National Park and Petrified Forest National Park.
The locations of fossils typically are not marked on maps to protect them from damage. It is important to note that fossils and trace fossils such as footprints are irreplaceable resources and it is illegal to damage or remove them in national parks.
Anytime you find a fossil, park paleontologists recommend you photograph it, note the coordinates and tell a ranger so a paleontologist can examine the specimen.
Where are fossils in Grand Canyon?
With over 1 billion years of the planet’s history preserved in the Grand Canyon, many kinds of life are represented in the rocks there — but no dinosaurs. The youngest rock layer in the canyon, the Kaibab Limestone on the rim, is about 270 million years old, which is older than the dinosaurs.
Park paleontologist Anne Miller said the Kaibab Limestone contains fossils of marine invertebrates like corals and sponges, but that’s not all.
“It also contains evidence of sharks, mostly their teeth,” she said.
One shark known specifically from that Kaibab Limestone is called the Kaibabvenator.
“This shark was just as big as the great white sharks that we see today,” Miller said.
Miller gave a critical piece of advice for anyone interested in seeing fossils at Grand Canyon: Do some research ahead of time to know what to look for. She recommends downloading the NPS Grand Canyon phone app before you go. You can look up a self-guided walk along the rim where you can see fossils right below your feet.
Fossil hikes and walks in Grand Canyon
Trail of Time: This 2.8-mile walk along the South Rim is a geologic timeline of the canyon’s history. Miller said this is a good place to see a sample of a stromatolite, a layered limestone structure made of sediment and fossilized cyanobacteria that lived in shallow oceans. Stromatolites are some of the oldest fossils in the park at over 1 billion years old.
South Kaibab Trail: This is one of the most popular trails and if you look carefully you will notice fossils. If you hike to Cedar Ridge (1.5 miles one way), you can spot plant and fern fossils in the Hermit Shale. “You’re basically hiking in a time machine. You’re going through ancient oceans, ancient beaches, deserts and swamps,” Miller said.
Hikers discovered tracks from an ancient reptile relative on the nearby Bright Angel Trail in 2017. More information on fossils in Grand Canyon National park can be found at https://www.nps.gov/grca/learn/nature/fossils.htm.
Where are fossils at Petrified Forest?
The name of the park gives it away: Most of the fossils you'll see at Petrified Forest are of exquisite petrified wood from the Triassic period over 200 million years ago. But many other fossils have been found here, including reptiles, amphibians and early dinosaurs.
These animals lived in a very different environment than what exists today, said Adam Marsh, paleontologist at Petrified Forest National Park.
“We were a lot closer to the equator ... we get evidence for big lakes,” he said.
Marsh said they find coprolites, or pieces of fossilized poop, and animal fossils in rock that, at the time, was “just the nastiest pond bottom you’d ever think of.”
Visitors can see fossil preparators working on specimens at the fossil demonstration lab, which is open 9 a.m.-3 p.m. Thursdays through Saturdays. It's in the visitor center at the north entrance to the park, which can be reached by using Exit 311 off Interstate 40 near Holbrook.
Marsh said Petrified Forest is teeming with easily seen fossils. Visitors are advised that it is illegal to remove anything from the park. He said visitors have found impressive specimens and anyone who does is asked to alert the staff to their find.
What is petrified wood?
The trees in Petrified Forest once were wood but now are are completely crystallized and mostly made of quartz.
Millions of years ago, the logs were buried by sediment and ash. Over thousands of years, the wood cells were slowly replaced by minerals in the groundwater. Elements like iron and manganese cause impurities in the quartz — and the beautiful colors.
Fossil hikes and walks in Petrified Forest
Red Basin Clam Beds: This 8.5-mile round-trip hike takes visitors past interesting rock formations and fossilized mollusks. Marsh said that even though the name refers to clam beds, “they are actual mussel shoals.”
Jasper Forest: This is a 2.5-mile round-trip hike where you will see substantial petrified logs and rock formations.
Both hikes are off the beaten path and visitors should consult the maps at https://www.nps.gov/pefo/off-the-beaten-path.htm. Be sure to bring plenty of water, sun protections and snacks, especially in summer. There's virtually no shade.
Are there dinosaur fossils in Arizona?
Traces of dinosaurs have been found in Arizona in the form of bones and footprints. There are preserved three-toed dinosaur footprints that are around 200 million years old near Tuba City on the Navajo Reservation north of Flagstaff.
Look for the signed turnoff along U.S. 160 about 5 miles east of U.S. 89. You'll likely be greeted by Navajo people offering tours and selling jewelry and art. You're not obligated to do either but it's a nice gesture. Wear a mask if social distancing is not possible.
Support local journalism. Subscribe to azcentral.com today.
This article originally appeared on Arizona Republic: Arizona: Where to find dinosaur tracks and fossils