New publication focuses on critical mineral potential in Kemmerer coals

The first Wyoming State Geological survey (WSGS) publication released in 2022 was an investigation into the geochemistry of samples retrieved from the Kemmerer coal field in western Wyoming. Specifically, the team of geoscientists assessed the potential of many critical and economic elements in the coal and its associated rocks.

Open File Report 2022-1, Trace Element Geochemistry of Coal Deposits in the Adaville and Frontier Formations, Kemmerer Coal Field, Wyoming, is part of a statewide investigation into potential occurrences of critical and economic minerals in Wyoming. Critical minerals are elements or mineral commodities that are essential for today’s economy but vulnerable to supply chain disruptions. Coal and associated rocks can contain critical minerals.

This study considers the geochemical data from coal and associated strata from the two major coal-bearing geologic units in the Kemmerer area, the Adaville and Frontier formations.

“We included as many critical minerals as we could analyze in an efficient and economic manner, and within the constraints of the preparation and analytical methods available,” says lead author, Kelsey Kehoe. Analyses were conducted in collaboration with the Aqueous Geochemistry Laboratory at the University of Wyoming’s Department of Geology and Geophysics.

The study found most beds showed similar and predictable distribution patterns for elements measured, with a few anomalous samples, suggesting the need for additional studies.

The WSGS has several additional investigations underway that examine critical mineral potential in Wyoming. One project is on the heavy-mineral sandstones found throughout the state. Geologists are also continuing their study of mineralization in the Medicine Bow and Laramie mountains. And this year, the agency will work toward gathering data on helium resources in the state, updating the last publication released in the 1990s.

Map of western Wyoming (figure 1 in the report), showing coal fields within the Hams Fork coal region, the extent of this study area, and the major faults associated with the Overthrust belt.

Study considers coalbed natural gas production effects on groundwater levels

The Powder River Basin in northeast Wyoming produced more than 6.1 trillion cubic feet of coalbed natural gas between 2001 and 2019. During the same timeframe, nearly one million acre-feet of groundwater from coal seams in the lower Tertiary aquifer system were also produced in the basin. Many of the basin’s 14,000 domestic, municipal, and agricultural wells utilize this system. 

Since 2019, coalbed natural gas production has dropped significantly. WSGS Report of Investigations 78—Groundwater Level Recovery in the Sandstones of the Lower Tertiary Aquifer System of the Powder River Basin, Wyoming—examines how groundwater levels in sandstone aquifers within the Wasatch and Fort Union formations have responded to declining coalbed natural gas and water production from nearby wells.

WSGS hydrologist, Karl Taboga, says the study analyzed groundwater level data collected by the Bureau of Land Management over the last three decades from more than 90 coal seam and sandstone wells at 39 monitoring sites. His investigation showed groundwater levels have declined by more than 100 feet in some deep sandstone aquifers that were more than 600 feet below the surface and separated from a producing coal seam by less than 200 feet. There were smaller declines in shallower sandstones that were more than 200 feet from a developed coal seam.

“Changes in coalbed natural gas production and produced water provide a unique opportunity to study long-term groundwater changes,” Dr. Erin Campbell, State Geologist and Director of the WSGS, said in a news release announcing the report’s publication. “Understanding how subsurface systems relate to groundwater recovery allow us to best plan future development.”

Two geologic maps from the central Laramie Mountains available 

In a unique collaboration with the U.S. Geological Survey (USGS) and multiple universities over the course of several decades, the WSGS published bedrock geologic maps of Poe Mountain and Guide Rock 1:24,000 scale quadrangles in the Laramie Mountains in southeast Wyoming.

Coauthor Dr. B. Ronald Frost, Emeritus professor at the University of Wyoming Department of Geology and Geophysics, said the maps were 30 years in the making. Originating at the USGS, the maps were delayed for many years after the death of fellow author, Dr. George Snyder. Frost approached the WSGS with the maps, and the agency agreed to publish them. Students from the UW Geology and Geophysics Department, and Dr. Donald H. Lindsley and students from the Department of Geosciences at Stony Brook University in New York also contributed to the maps.

The maps contribute significantly to our understanding of the geology of the central part of the Laramie Mountains. The quadrangles straddle the Albany-Platte county border and host the 1.4-billion-year-old Laramie Anorthosite Complex, which contains many groups of igneous rocks. This includes the Poe Mountain anorthosite.

Guide Rock on the Guide Rock quadrangle.

Recap of Survey's 2021 publications

In continuing its effort of interpreting Wyoming’s complex geology and sharing it with the public, the WSGS released nearly a dozen new publications in 2021. Half of the publications are geologic maps of quadrangles in Sweetwater, Albany, Laramie, Platte, and Teton counties.

The WSGS released two reports last year—one examining the mineralogy and geochemistry of a heavy-mineral deposit in southwestern Wyoming, the other establishing a baseline dataset for the stratigraphy and geometry of potential unconventional reservoirs in the Greater Green River Basin.

Two information pamphlets about Hot Springs and Boysen state parks were released, wrapping up a series that highlighted geology in Wyoming’s state parks.

Geoscientists also updated the interactive Oil and Gas Map of Wyoming in 2021. The map is updated every year with the latest data. It is free to use and readily accessible with any up-to-date web browser.

Reports:

• Oil and Natural Gas Resources in Wyoming Summary Report
• Greater Green River Basin Formation Tops Database, Structure and Thickness Contour Maps, and Associated Well Data, with a Focus on Potential Continuous Reservoirs
• Heavy-Mineral Sandstone in the Upper Cretaceous Rock Springs Formation, Richards Gap, Wyoming

Maps:

• Preliminary Geologic Map of the Richards Gap Quadrangle, Sweetwater County, Wyoming, and Daggett County, Utah
• Preliminary Geologic Map of the Goat Mountain Quadrangle, Albany and Laramie counties, Wyoming
• Preliminary Geologic Map of the West Half of the Jackson Lake 30' x 60' quadrangle, Teton County, Wyoming
• Preliminary Geologic Map of the Rock River 30' x 60' quadrangle, Albany, Platte, and Laramie counties, Wyoming
• Geologic Map of the Poe Mountain Quadrangle, Albany and Platte counties, Wyoming
• Geologic Map of the Guide Rock Quadrangle, Albany County, Wyoming

State park information pamphlets:

• Geology of Boysen State Park
• Geology of Hot Springs State Park

Publications can be downloaded for free by following the above links. Some are available as hard copies, call (307) 766-2286 to inquire.

Reports offer snapshot of Wyoming’s oil and natural gas, minerals industries

The WSGS released a pair of reports that provide brief summaries of Wyoming’s oil and natural gas, and mineral industries in 2021. These reports are published at the start of every year and offer the public a snapshot of some of the state’s most important economic sectors.

Oil and natural gas production increased gradually last year in part due to price volatility and demand uncertainty, according to the oil and natural gas summary report. The report also emphasizes the importance of pipeline infrastructure, new and associated hydrocarbon products, and innovative projects for the state’s ongoing economic recovery.

The minerals summary report focuses on critical mineral resources in Wyoming. WSGS scientists are studying the statewide occurrence and distribution of these minerals, which have national interest.

The minerals report also summarizes ongoing and historic production of critical minerals, provides an update on recent exploration and development activity in Wyoming, and details promising deposits in the state.

WSGS nabs top award

The WSGS was honored with a national award from the Association of American State Geologists (AASG) for the agency’s 2020 publication about the subsurface of Wyoming’s hydrocarbon-rich Powder River Basin.

Open File Report 2020-9, titled, Upper Cretaceous Strata from the Powder River Basin: Formation Tops Database, Structure and Thickness Contour Maps, and Associated Well Data, earned the 2021 Charles J. Mankin Memorial Award, which is one of the AASG’s most prestigious publication honors. The award is a tribute to former Oklahoma Geological Survey Director, Charles Mankin, who served in the post for 40 years. State geological surveys around the nation nominate geological maps, compilations, or reports on regional, energy, or mineral resource geology for the award.

Derek Lichtner, Rachel Toner, Jackie Kleinsasser, and Ranie Lynds authored the WSGS report, which details the Upper Cretaceous stratigraphy associated with the Powder River Basin’s unconventional tight oil and gas reservoirs, their source rocks, and intervening formations.

“Derek and the rest of the team have created an outstanding report,” Dr. Erin Campbell, WSGS Director and State Geologist, said in a December news release announcing the award. “They expertly assessed the needs of the state and produced a publication that directly addresses our mission of promoting the beneficial and responsible development and use of Wyoming’s geologic, mineral, and energy resources.

“Publications like this will be used by industry and academia for decades to come, helping to drive investment in the state as well as developing a broader understanding of the geologic history of eastern Wyoming from about 100 to 70 million years ago,” Campbell added.

The report can be downloaded for free from the WSGS website, and includes links to the full supplemental dataset as well as the option to view the associated maps on the Survey’s Interactive Oil and Gas Map of Wyoming.

Director's corner: Yellowstone National Park celebrates milestone

Yellowstone National Park is celebrating its 150^th birthday this March! Yellowstone was established in 1872 as the world’s first national park, and as any fan of geology knows, it was created to preserve the area around the Yellowstone volcano.

Much of Yellowstone National Park sits atop an active volcano, and it has enjoyed eruptions, lava flows, faulting, and ground movement over the past 2.1 million years. The rock record preserves three major explosive eruptions from the Yellowstone area, which created giant calderas; the first was the largest, erupting 2,450 kilometers of rock and ash about 2.1 million years ago. The most recent eruptions, between 180,000 and 70,000 years ago, were thick lava flows rather than catastrophic caldera-forming eruptions. 

Yellowstone will erupt again, but rest assured that the myth of an imminent “supervolcano” eruption is just that—a myth. Yellowstone is not “overdue” for an eruption, because volcanoes do not erupt at regular intervals, they erupt when magma moves into the chamber beneath the volcano. That magma may escape through fissures in the crust and pour out gently as lava flows, or burst through the surface as violent explosions. If either of these occur, we will have plenty of warning, as Yellowstone is under constant surveillance by the Yellowstone Volcano Observatory (YVO). The YVO is part of the USGS, but involves researchers from around the country, including two hazards geologists from the WSGS.

So how is Yellowstone monitored? When magma starts to move beneath the volcano, it creates a series of earthquakes. YVO scientists have established seismometers throughout the volcanic system to record those earthquakes; you can view recent earthquakes here: https://quake.utah.edu/earthquake-center/quake-map.

Additionally, when magma starts to collect beneath the volcano, the surface will rise, and when that magma moves elsewhere or erupts, the surface will subside. We may also see changes in topography as active faults move. All of these changes at the surface are monitored via satellite using GPS (Global Positioning System) and InSAR (Interferometric Synthetic Aperture Radar), which are high-resolution techniques that measure ground deformation continually and over long periods of time.

If you celebrate Yellowstone’s milestone birthday this year by visiting the park, you can do so worry free, knowing that you won’t be surprised by an eruption.

--Dr. Erin Campbell, WSGS Director and State Geologist