Discovered by white settlers in the area as early as 1859, located in the Pioche Hills of eastern Lincoln County, and most easily seen at the Oak Spring Trilobites Site, between mile marker 81 and 82, a little south of Oak Springs Summit, off U.S. Highway 93, is a formation of small prehistoric sea creatures and plants.
Seldom visited, it creates part of the Lower-Middle Cambrian boundary interval within the southern Great Basin and Mojave Desert region.
The entire Caliente Elementary School visited the site Nov. 13.
School Principal Pam Teel said the children had intended to go out to the Delamar Flats to watch some of the touch-and-go exercises by jet planes from Nellis Air Force Base, but the Air Force canceled their practice just that morning.
“We were already to go somewhere,” Teel said, “so we thought why not the Trilobite site, very few of us from the County have really ever been there, although we have all passed by the sign on the highway many times.”
The whole school went, 127 children, kindergarten through sixth grade, 17 teachers and staff, and a few parents, in two yellow limousines and pickup trucks.
She said, “State Park Ranger Cody Tingey (at Cathedral Gorge) met us up there and we walked the little trail from the parking area up to the sites and we had a good time looking for and talking about Trilobites which are fossils.”
A brochure from the park headquarters at Cathedral Gorge notes a Trilobite is, “a little animal that lived in the sea, with a shell like a horseshoe crab, jointed legs, and antennae. Its eyes were compound, like a fly, and it could curl up like a pill bug.”
Teel said, “We told the kids, in class groups, to find three that they liked the best. After that, we went to the BLM campgrounds on Oak Summit and saw the ATV trailhead, did some short hikes, and ate lunch.”
Tingey had originally prepared to do a talk about the Delamar Flats area, a dry lake bed locally known as Jumbo, or Texas Lake by the Air Force. “But he also knows information about the Trilobites,” Teel said. “He is a wealth of information and was even taking questions about the trees up there.
Whatever the kids were asking, he was able to help answer.”
Teel said very few of the people from the school, even staff, had ever been up there. “It was an alternative plan, but it worked out really well.” A couple of classes from Caliente Eliminatory had been out there a couple of years ago, Teel noted, “so it was a good place to go for something educational. Reality is, we have many people in the County itself that have not visited there. It was a huge learning context with just a lot of things. A very, very good day.”
Tingey said he showed the kids what to look for, how to find the Trilobite fossils and the ancient plants also pressed into the dried mud.
He said the area is a transition zone between different types of vegetation. “As you come out of the desert dry lake beds, the Joshua trees and Yucca plants, you move more into the Pinyon and Juniper area in the mountains.”
Just east of Dry Lake Valley, the Trilobite site is part of the long outcrop and belt that occurs within a mountain chain which trends southward along the west side of the Bristol, Highland, Chief, and Burnt Springs Ranges to Lime Mountain in the Delamar Mountains.
These areas are rich in fossilized trilobites within the prehistoric Cambrian shelf. A transect shows the depth changes across the prehistoric ocean known as the inland sea, a region now known as the Great Basin.
Geologists say over 520 million years ago, an ancient sea covered the Great Basin, about six miles deep. Between 60 to 35 million years ago the ancient sea bed was folded, uplifted, and eroded. Some 15 million years ago, volcanos centered near Caliente buried all the earlier rocks, containing the fossils, under hundreds of feet of lava.
Today, massive blocks of former volcanic flows and ancient sea bed limestone that had been moved and broken by ancient earthquakes, and eroded by wind and water can be viewed in certain places, like the Oak Springs Trilobite site.
The Great Basin covers about 189,000 square miles, (just over 120 million acres), including Death Valley and Bonneville Salt Flats, and is found between the Sierra Nevada Mountains to the west and the Wasatch Range in Utah to the east, up north into south central and southeastern Oregon, and nearly to Las Vegas in the south.
An interesting fact: the rivers in the Great Basin have not outlet to the Pacific Ocean, they either dry up in the deserts, or empty into large lakes, such as Tahoe, Walker, Pyramid, and Great Salt Lake, which are the last major remnants of what scientists say was a huge prehistoric lake. Named Lake Bonneville, some 30,000 years ago, it was similar in size to Lake Michigan.