40 Years at Prudhoe Bay: Young geologist changed Alaska history

Lands selection officer convinced state leaders to gain control of petroleum-rich North Slope acreage before Prudhoe Bay discovery

Rose Ragsdale

For Petroleum News

Like so many other young adventurers, Tom Marshall came to Alaska in 1958 to homestead on federal lands.

Marshall, a young geologist from Wyoming, also was eager to get in on the ground floor of the Cook Inlet oil exploration boom touched off by the Swanson River discovery in 1957.

“I also wanted to see if Alaska was the magnificent place that my grandfather Marshall said it was,” he told members of the Alaska Geological Society in April 2008. The elder Marshall had traveled to Alaska decades earlier as a member of the Royal Canadian Mounted Police.

From his first days in Alaska, the younger Marshall recalls clearing land at a cost of about $1,000 per acre.

“Homesteading was very hard on personal finances,” he said in explaining his decision to accept a position with the very young Alaska state government as an assistant lands selection officer.

“It looked very appealing as a means to get me through the winter,” he said.

Marshall, a University of Colorado-trained geologist, was asked to evaluate a federal opening for land selection on the North Slope in 1958.

Marshall said his principal source of information in preparing for the selections was professional papers published by the U.S. Geological Survey, which were crammed with lots of information about the Navy’s exploration program in the 1940s and 1950s.

Similarities to Rocky Mountain areas

A year later, Alaska, as part of its land entitlement under the Statehood Act, selected more than 1.8 million acres of the Arctic coastal plain bordering the Beaufort Sea between what is now the National Petroleum Reserve- Alaska and ANWR.

It was an area the federal geologists had declared impossible to survey and estimated it would take 100 years to accomplish the task.

Marshall, who had been promoted to state land selection officer, enthusiastically recommended the swampy lake-covered area, which contains no surface rock exposures, be included in the state’s land selections because he found general geological similarities of the Arctic Slope to petroleum-bearing areas in the Rocky Mountains.

“Regional geology is what I used in my selection criteria because it had meaning to me. I transferred my Rocky Mountain oil and gas exploration experience,” said Marshall. He also observed that the same USGS publications he studied were available to the Bureau of Land Management and the oil companies, “but they had their own ideas.”

Ironically, the state Division of Lands polled seven companies and none of them recommended the Prudhoe Bay area for lease.

The oil companies wanted to drill in the area around the Colville basin, not on the Arctic coast.

During his investigation, Marshall said he noticed the 2,000- to 2,500-foot Lisburne Limestone over a broad area with all sorts of porosity.

“It excited me because back in Wyoming, we had the geologic equivalent of the Lisburne Limestone in our Madison Limestone, which had been in many areas of Wyoming, including Casper where I lived for many for years,” Marshall said.

He said the Lisburne Limestone was an unattainable 20,000 feet deep in the Colville Trough, and the limestone was probably at that latitude in the Umiat oil field.

“This was definitely considered an uneconomic depth,” Marshall said. “But regional geology to me means there would be a rise from the Colville Trough up to the Barrow Canyon Arch on the Beaufort Sea shore. It would be a terrific gathering area for petroleum and maybe there would be a big oil field there.”

Leaders believe in “big banana”

Marshall’s selections were the first ever made by the state that had no known surface uses.

Luckily for Alaska, Holdsworth and Bell had faith in Marshall’s judgment.

Other Alaska leaders were skeptical.

Marshall said he received calls from politicians in Juneau wanting to know what the basis was for “Arctic waste land selection.”

Other taunts included “Marshall’s icebox” and “Marshall’s folly.” Fellow homesteaders dubbed the land selections “worthless tundra.”

Perhaps the cruelest taunt came later after some very disappointing dry holes were drilled on the Colville and at Union’s Kookpuk well from those who had witnessed Marshall’s earlier enthusiasm and who suggested that “there might be just the ‘banana skin,’ up there,” Marshall recalled.

It turned out that selection of the coastal plain area offered an additional advantage because it eliminated potential future disputes between the state and federal governments over the definition of navigable streams in upland areas. If the surrounding lands were state lands, it thus became unnecessary to define the limit of navigability of streams flowing into the Arctic Ocean.

The lands thus selected included Prudhoe Bay.

Trail leads to Prudhoe Bay

In this sale, the state took in a total of $5.6 million in bonus bids for leases covering acreage in the Kuparuk-Ugnu area of the North Slope. Though it wasn’t a huge sum, it was enough to cover the state’s land selection filing fees and compensate for its loss of highway funds for the entire North Slope.

Marshall was ecstatic.

Richfield Oil Co. picked up more than 71,500 acres of land covering the crest of a subsurface geological structure on the shores of Prudhoe Bay in the July 1965 sale.

British Petroleum, following theories developed by its geologists, acquired nearly 82,000 acres lower down the flank of the Prudhoe Bay structure.

Nearly three years later, Atlantic Richfield Co. announced discovery and confirmation of the Prudhoe Bay oil and gas field, which 40 years later, remains North America’s largest petroleum reservoir. In a matter of months, “Marshall’s folly” had changed the course of history, becoming the single-most important source of revenue for the State of Alaska.

Wrong theory, right location

“I don’t want to sound too smart about the discovery, because frankly, I was dead wrong. I had read reports about the Sadlerochit Sandstone and the Ivishak Formation. They were described as being primarily quartzite, which has to be zero porosity. I couldn’t see outcrops of these Ivishak Sands in the information I had about the region across the broad Slope, and it didn’t seem to impress the USGS geologists who studied them in the Foothills area,” he explained. “But as we know, the Prudhoe Bay discovery was primarily in the Ivishak sands of the Sadlerochit Formation, which I did not even consider. I thought it was going to be the Lisburne. Fortunately, it’s in both of them. But the Lisburne is a far distant third or fourth largest reservoir on the North Slope.”

Marshall’s modesty notwithstanding, the significance of his contributions cannot be underestimated.

Doing his job as a state employee, Marshall essentially shaped a critical component of Alaska’s destiny.

Others who participated in the Prudhoe Bay discovery say Marshall deserves considerable credit for the state owning the acreage where the Prudhoe Bay field is located.

“Tom Marshall deserves a monument for persisting in getting the state to select the acreage where the discovery of Prudhoe Bay was made. He fought tooth and nail from his appointment in 1960 until he convinced the governor in 1963 to make the selections on the North Slope,” said John Sweet, Alaska district explorationist for Atlantic Richfield Co. at the time of the discovery.

The Alaska Legislature has honored Marshall for his work, and Sweet told the Alaska Geological Society in April that it should ask the geosciences department at the University of Alaska to name a permanent chair in honor of Tom Marshall.

“He deserves it,” Sweet added.