Buried Treasure: Oil & Gas Exploration Leaves Undiscovered Artifacts

Southeast Wyoming is buzzing with oil and gas activity. But while companies look for minerals thousands of feet below, other resources will remain buried just under the surface.

Over the past 12 months, land agents have been calling on property owners from Cheyenne to Douglas. Seismic surveyors have thumped the ground in Laramie, Goshen, Platte, Niobrara and Converse counties. Developers have drilled dozens of wells, searching for sweet spots of oil in the Niobrara shale and other formations.

As companies explore thousands of square miles of southeast Wyoming, they traverse lands with a long human history and a much longer fossil record. On U.S. public lands, federal law guides the management of those cultural resources.

But this oil play is happening mostly with privately owned land and minerals, where there are no federal laws to protect cultural resources. The only exceptions are a few archaeology surveys of federal mineral parcels.

That means stewardship of cultural resources in this region falls to landowners.

“Archaeological sites are protected by federal and state law and private landowner interests,” said state archaeologist Mark Miller. “It’s nice to preserve that record until we have time to look at it and investigate it.”

Landowners are accustomed to protecting their property from trespass and vandalism. But it’s rare for them to ask energy companies for cultural resource surveys or excavation. As a result, many cultural sites in southeast Wyoming are likely to remain undiscovered.

“The Niobrara play that is starting here is private mineral, so we’ll never see anything from that,” said Richard Currit, senior archaeologist at the Wyoming State Historic Preservation Office.

By contrast, energy development on public land in western Wyoming led to comprehensive cultural resource surveys in places like Jonah Field and the Pinedale Anticline.

Those surveys led to unusual finds in places where no one had looked before. The construction of well pads in the Pinedale Anticline uncovered ancient pit houses dating back 8,000 years.

“There are probably close to 2,000 sites in the Anticline and more than 2,000 sites in the Jonah Field,” said Dave Crowley, a U.S. Bureau of Land Management archaeologist at the Pinedale Field Office.

Crowley said he couldn’t predict what might be found in southeast Wyoming, but he said experience has taught him that private lands are a good place to find artifacts.

“There’s tons of stuff all over the state,” Crowley said. “There’s probably more stuff on private land than there is on public land. That’s because arrowhead hunting has been a popular pastime for at least 100 years. Sites on public land have been picked over.”

Crowley said environmental factors can create a nexus between private land and archaeological resources.

“Most of the private land in Wyoming was homesteaded along rivers, and that’s where a lot of good (archaeology sites) are found,” Crowley said.  “A good place to live thousands of years ago is a good place to live now.”

Most of Wyoming’s archaeological and fossil resources have yet to be discovered, and some of them may lie within the Niobrara oil play.

“Based on how much archaeological evidence we’ve found here in the (Sublette County) gas fields, I would think there’s a good chance to find things over there in southeast Wyoming,” said Clint Gilchrist of the Sublette County Historical Society. “If I was looking over there I would think of it as a great opportunity to try to work with those private landowners and find some cool stuff.”

What’s Out There

Wyoming is a land rich with evidence of past human activity. “Humans have occupied portions of Wyoming for at least 13,000 years, and there have been some economic reasons for that,” Miller said.

Places like Spanish Diggings, east of Glenrock, show evidence of mining activity, where early inhabitants dug out seams of quartz for arrow points.

The state is also rich in archaeological sites relating to historic migration, like the Oregon Trail ruts near Guernsey.

But the majority of archaeological sites are not so obvious.

“Unless, for some reason, you’re digging up the ground, you’ll never find those resources,” Gilchrist said.

The same is true for paleontology sites. In 2006, Kelli Trujillo and Dave DeMar were inspecting a trench just outside of Laramie that Kinder Morgan was digging for its Rockies Express Pipeline. By chance, the trench intersected with a submerged portion of the bone-rich Morrison Formation.

Trujillo noticed the broken surface of a vertebra. Subsequent excavations uncovered a spine from a 150 million-year-old sauropod, several allosaurus teeth, crocodile teeth, a turtle shell and part of another unidentified dinosaur. These were notable discoveries on the Laramie Plains, an area not known for containing fossils.

Another unexpected discovery occurred in western Wyoming in 2000, when workers constructing well pads at Jonah Field stumbled across the remains of 10 prehistoric pit houses.

Between 2000 and 2002, excavations uncovered ancient houses that measured up to 15 feet across. They had submerged floors with fire hearths, along with the remnants of posts and brush that would have formed a sturdy and cozy roof structure. Ancient people may have used the houses as way stations on a route between the Wind River Mountains and the Wyoming Range.

Carbon dating of fireplace ashes indicated that the pit houses had been inhabited during at least 11 separate occasions stretching over a period of 2,600 years.

In all, archaeologists found 34 pit houses at 25 different sites in Sublette County, Crowley said. The discoveries contributed greatly to our knowledge of how people lived in the area during the era known as the Archaic Period. But they represent just a fraction of the region’s cultural resources.

Combined with the estimated 4,000 sites in the Pinedale Anticline and Jonah Field, there are “more than 7,000 archaeological sites recorded in Sublette County,” said Crowley. His Pinedale BLM office discovers about 500 new sites each year.

That density of sites is not unusual.

“There tend to be more sites found in counties with energy development as opposed to counties with no energy development,” Miller said.

That’s because counties without energy development aren’t surveyed nearly as much.

“Somewhere on the order of 9 percent of Wyoming has been systematically surveyed by various (archaeology) professionals,” Miller said.

Across that area, professional and vocational archaeologists have located approximately 90,000 sites ranging from ubiquitous caches of arrow points, to gems like Castle Gardens petroglyphs, the Medicine Wheel of the Bighorn Mountains, and the Vore Buffalo Jump. The latter provides such a significant record that it has been called “the Pompeii of the Plains.”

If distribution were even across the state, Miller says Wyoming could contain nearly 1 million archaeological sites.

The Wyoming State Archaeology Repository at the University of Wyoming houses a tremendous volume of information and artifacts collected by archaeologists. Curator Mary Rogers says the repository contains more than 1 million items. Efforts to catalog and curate these materials are expected to continue for the next 25 years.

Private Land, Private Artifacts

Much of our knowledge about Wyoming’s past has been collected since the passage of Section 106 of the National Historic Preservation Act in 1966. The law states that development of federal land or minerals can proceed only after a survey to evaluate if the site is worthy of inclusion in the National Register of Historic Places.

In 2009, a new law called the Paleontological Resources Preservation Act laid out a similar process for the management of fossils on federal land.

These laws have created an entire industry of archaeologists and paleontologists to oversee the survey process. They work in private firms, the BLM and the State Historic Preservation Office.

Still, there’s no law requiring a cultural resources survey on private land with private minerals. The surface owner owns all artifacts on the land – everything from dinosaur bones to bison skulls and cavalry bullets. The National Historic Preservation Act cannot dictate how private landowners should deal with such materials.

“That’s a good thing,” said State Archaeologist Mark Miller. “My first career was as a rancher in Wyoming…You must respect private land or you run into trouble.”

Representatives from industry agree with this line of thinking.

“One of the things that makes this country great is that people have private land, and they have the right to make the decisions associated with their property,” said Bret Schafer, regional manager of Dawson Geophysical Company.

His company conducted seismic surveys in Converse County over the past few months.

For those interested in preservation, the risk of development harming artifacts on private land creates mixed feelings.

“Being someone that really cares about history, I’m concerned that we’re going to lose some of the cultural resources on private ground,” said Gilchrist. “But the other side of it is I’m a lifelong Wyoming resident and I own property myself and I very much support private property rights.”

For that reason, preservation efforts must occur through collaboration between the landowner and the energy developer, Gilchrist said.

“Most landowners are very good stewards of their own land. They take care of it and want it to remain like it is and not torn up,” Schafer said.

Indeed, Wyoming landowners are notoriously protective — even secretive — about cultural resources on their property.

The diligence is mirrored by best practices of industry. Schafer says that Dawson Geophysical crews follow a policy of avoiding all artifacts they come across in their seismic work, whether on private or public land.

“We put a buffer zone on it and leave it intact and leave it alone. We try very hard to have minimal impact,” Schafer said.

It’s easy enough to shift the seismic line and fill in the missing information by mathematical extrapolation, he added. Nonetheless, some artifacts won’t be discovered without a formal survey.

“You’ve got to be pretty well-trained to be able to pick things up,” Schafer said.

Some oil company executives assert that the risk of damaging cultural resources is a non-issue in farming areas of southeast Wyoming. Terry Barr, managing director of Samson Oil and Gas, hired the company Geokinetics to conduct a 60-square-mile seismic survey in Goshen County last fall.

Barr said 95 percent of the survey covered irrigated agricultural land, which has been under the plow for more than 100 years. Any artifacts there would have long since been plowed and harrowed into dust. Barr’s greater concern was that his survey not damage crops, which explains why seismic crews started work in November, after the fall harvest.

But outside of the irrigation projects along the Laramie and Platte Rivers and the dry land wheat fields on the higher plateaus, much of southeast Wyoming is private unplowed grazing land where companies could encounter cultural resources.

Protecting the Past, Wyoming Style

With all this private land lying in the path of what may be the state’s most wide-ranging oil exploration in recent memory, how can landowners be sure of not destroying their cultural and fossil resources before they even know what’s there?

For many, the answer isn’t placing restrictions on landowners or regulations requiring that they complete surveys prior to exploration.

“I would hate to see laws that started dictating what people have to do on private property,” Gilchrist said.

Gilchrist said he believes coercive efforts at preservation can backfire.

“Laws that try to preserve historic or cultural materials on private ground…create an adversarial relationship with people who have resources when you try to enforce the rules,” said Gilchrist.

Instead of creating more rules and bureaucracy, Gilchrist said the best solution may be for nonprofit organizations to work with landowners and ask oil operators to collaborate and help fund the preservation of various resources.

“It would have to be volunteer on all sides,” Gilchrist said.

If such an effort sounds like a fairy tale, consider last year’s preservation of the New Fork River Crossing of the Lander Trail. As BLM officials started to negotiate with Shell and Ultra Petroleum about mitigating impacts on cultural resources, Gilchrist and other local preservationists pointed out a pristine piece of land containing a river crossing of the Lander Trail that was up for sale.

In a collaborative effort, Shell, Ultra and Rocky Mountain Power agreed to purchase the private 82-acre parcel along the New Fork River and donate it to the Sublette County Historical Society.

The project to preserve the New Fork River Crossing proceeded with the approval of the BLM, the Wyoming State Historic Preservation Office, the National Park Service and the Advisory Council on Historic Preservation. It also garnered the support of organizations like the Oregon-California Trails Association and the Alliance for Historic Wyoming.

In return, Shell and Ultra received permits to drill more wells within a 3-mile resource management buffer along the Lander Trail. Rocky Mountain Power earned credit for mitigating impacts of a power line that passed through the Pinedale Anticline. And the public gained access to a historic trail crossing that looks much as it did in the 1860s.

The effort could serve as a collaborative model for preserving cultural resources on private land in the Niobrara oil play. Nonprofit organizations could help landowners negotiate for cultural resource surveys that developers would pay for. But so far, nothing like that is happening in southeast Wyoming.

Ironically, some believe that keeping cultural resource sites undiscovered and unknown to everyone except the landowner may be the best way to preserve them. After all, when a survey on federal land discovers a site that developers cannot avoid, excavations end up destroying the site piece by piece as archaeologists gather all the knowledge that lies within.

“It’s a double-edged sword,” said Currit. “They are finding things we would absolutely know nothing about, but they are also being destroyed by the activity.”

So perhaps those who care about preserving an intact record of our predecessors for future generations should hope that relics remain buried just outside the path of the seismic truck — or that new well pads, roads and pipelines bypass fossils. Those untouched sites will endure, waiting to tell the story of Wyoming’s past long after we are gone.

Greg Nickerson is a writer, historian and filmmaker from Big Horn. Contact him at 307-752-6031 or gregory.m.nickerson@gmail.com.