Current Projects
Minerals
Pair of Projects Focus on Heavy-Mineral Sands
Heavy-mineral sand placer deposits, sometimes called “black sands,” are the world’s primary source for titanium and zirconium, as well as a potential source for hafnium, niobium, vanadium,
and the rare earth elements. These elements are considered by the USGS to be “critical minerals,” which are essential to the economic and national security of the United States.
A “heavy mineral” is an accessory detrital mineral with high density relative to quartz and feldspar, the two most common minerals in sands and sandstones. Because of their high density,
heavy minerals are subject to mechanical sorting during transport in rivers and along shorelines. A placer deposit can form if the sorting process produces a significant accumulation of
concentrated heavy minerals. In Wyoming, such deposits are found as paleoplacers (fossil placers) in various rock formations, including the Cambrian Flathead Sandstone, Cretaceous Mesaverde
Group, and in some Precambrian and Eocene rocks.
In an effort to better characterize the chemistry and mineralogy of these deposits, the WSGS is studying heavy-mineral sandstones of all ages statewide. For this project,
the main goal is to conduct preliminary sampling and analysis of the heavy-mineral
sand deposits for which data are scarce or nonexistent, as well as to augment older datasets with modern analytical methods, with a focus on the rare earth elements.
Geochemistry and Geochronology Reconnaissance of the Medicine Bow Mountains
The WSGS is conducting an analytically intensive
geochemistry and geochronology reconnaissance project
in the Medicine Bows Mountains.
The Medicine Bows have high potential for critical mineral deposits vital to U.S. growth and stability. The area’s complex geology, including the
juxtaposition of the Archean Wyoming Province with the accreted Colorado Province terranes along the Cheyenne Belt and associated shear zones,
multiple episodes of mafic and felsic intrusions, thick packages of metasediments and metavolcanics, possible later metamorphic events, and Laramide uplift,
suggest that diverse mineral systems exist within the Medicine Bows.
Historical mining in the area has confirmed the existence of economically viable gold, silver, copper, platinum group elements, and minor uranium and rare earth element deposits.
Historical mining efforts also noted the existence of metals now considered critical, the presence of which has been confirmed by subsequent scientific studies. However, geochemical
data for the region are not available in a comprehensive public database. Pre-existing data are inconsistent in methodology, elements analyzed, spatial coverage, and public availability.
This project will develop and conduct an exhaustive sampling program to target areas of known and unknown mineralization in shear-hosted veins; layered mafic-ultramafic intrusions and
associated felsic intrusions along the Cheyenne Belt; felsic intrusions, pegmatites, and vein systems in the accreted Proterozoic terranes; Precambrian sulfide-rich metasediments and
metavolcanics; radioactive paleoplacers; and REE- and uranium-rich pegmatites. The study area encompasses the entire Wyoming portion of the Medicine Bow Mountains—a Precambrian-core
Laramide uplift.
This project will directly complement the airborne magnetic and radiometric
survey scheduled for summer 2023 in the Medicine Bow and eastern Sierra Madre mountains. The goal is an integrated understanding of the geochemical, structural, petrological, and
deformational processes that make up regional mineral systems; this will have the potential to aid mineral exploration efforts not only in the Medicine Bows, but also in areas with a
similar geologic history, such as the Sierra Madre range to the west and elsewhere along the trend of the Cheyenne Belt.
Potential critical minerals in the project area: antimony, arsenic, barium, beryllium, bismuth, cobalt, chromium, fluorspar, gallium, germanium, hafnium, indium, magnesium, manganese,
nickel, platinum group elements, scandium, tantalum, tellurium, tin, vanadium, zinc, and zirconium.
Medicine Bows—Geophysics
A high-resolution magnetic and radiometric survey, planned for acquisition in summer 2023 in the Medicine Bow Mountains, is designed to optimize coverage of geologic features of greatest interest.
The effort is focused on the Lake Owen Complex, a Paleoproterozoic layered mafic intrusion with known PGE mineralization, and the surrounding area that includes the Cheyenne Belt,
which marks the southern margin of the Wyoming Province. The planned survey includes magnetic and radiometric data collected from a helicopter along flight lines spaced no wider
than 200 meters and a nominal terrain clearance of 60–120 m. The mineral systems of interest in the survey area include mafic magmatic, magmatic rare earth elements, placer,
porphyry Cu-Mo-Au, and volcanogenic seafloor. Potential critical mineral commodities: antimony, arsenic, barium, beryllium, bismuth, cobalt, chromium, fluorspar, gallium, germanium,
hafnium, indium, magnesium, manganese, platinum group elements, rare earth elements, scandium, tantalum, tellurium, tin, vanadium, zinc, and zirconium. There is additional potential
for silver, gold, cadmium, copper, iron, lanthanum, lead, molybdenum, thorium, uranium, and yttrium.
Sierra Madre-Elkhead Mountains-Medicine Bow Mountains—Geophysics
A high-resolution magnetic and radiometric survey is planned for acquisition in summer 2023 in the greater Sierra Madre-Elkhead Mountains-Medicine Bow Mountains region along the
Wyoming-Colorado border. The survey is funded by the USGS Earth MRI and is designed to meet complementary needs related to geologic mapping and mineral resource research. The survey
design is coordinated with the WSGS, Colorado Geological Survey, and staff from the National Cooperative Geologic Mapping Program to optimize coverage of geologic features of greatest
interest. The survey is also designed to adjoin and augment the previously planned Medicine Bow Mountains airborne magnetic and radiometric survey that will also be flown during summer 2023.
The effort is focused on the Cheyenne Belt corridor along the southern margin of the Archean Wyoming Province, a region that contains several known and suspected mineral systems of high
interest for their critical mineral potential. There has been abundant past and current exploration and mining, although exploration efforts are hampered by a lack of high-quality
geophysical data. Several fundamental questions on the region's structure and Paleoproterozoic tectonomagmatic evolution are also unresolved.
The airborne survey data are further expected to aid mapping of suspected Quaternary faults and elements of the geology important to groundwater resources in the Saratoga Valley.
The planned survey includes magnetic and radiometric data collected from a helicopter along flight lines spaced 200 meters and a nominal terrain clearance of 100 m. Parts of the survey
area may be suitable for a fixed-wing aircraft.
The mineral systems of interest in the survey area include Climax-type, mafic magmatic, magmatic rare earth elements, placer, porphyry copper-molybdenum-gold, and volcanogenic seafloor.
Potential critical mineral commodities: antimony, arsenic, beryllium, bismuth, cobalt, chromium, fluorspar, hafnium, gallium, germanium, indium, magnesium, manganese, nickel, niobium,
platinum group elements, rare earth elements, scandium, tantalum, tellurium, tin, vanadium, and zirconium. There is additional potential for cadmium, copper, gold, iron, molybdenum, lead,
selenium, silver, vermiculite, and uranium.
Western Phosphate Field—Geochemistry
The WSGS is part of a four-state cooperative effort, administered by the Idaho Geological Survey and funded by the USGS Earth MRI program, to evaluate the enrichment of
critical minerals
in the Permian Phosphoria Formation. Exposures of this formation occur across 350,000 square kilometers in Idaho, Utah, Wyoming, and Montana, and it is one of the largest commercial
resources of phosphate rock in the world. Mining of the Phosphoria Formation in this region, referred to as the Western Phosphate Field, has provided phosphorus for the fertilizer industry
since the early 1900s.
The Phosphoria Formation formed within a marine chemocline system, and includes a succession of black organic-rich mudstones, siltstones, phosphorites, carbonates, and cherts deposited
265 million years ago on the western margin of North America. The richest phosphate deposits are in the Meade Peak and Retort members, which both display considerable lithologic and
stratigraphic variability. Previous studies have shown that elevated levels of rare earth elements and other critical minerals are concentrated within phosphorites and black shales
in these two members.
The project centers on collecting new geological and geochemical data primarily from the Meade Peak and Retort members. Data are being acquired along measured stratigraphic sections
in the context of a basinwide framework and at locations considered strategic from a mineral resource or scientific standpoint (for example: suitable outcrops, mine exposures, and
archived drill core). The objective is to construct geologic models that assess and delineate the critical mineral resource potential of the Western Phosphate Field in order to
provide an enhanced understanding of marine chemocline mineral systems. Potential critical minerals in project area: chromium, fluorine, rare earth elements, and vanadium.
South Pass and Granite Mountains—Geophysics
A high-resolution magnetic and radiometric survey is planned for acquisition in summer to fall 2023 in the greater South Pass-Granite Mountains region in central Wyoming.
The survey is designed to optimize coverage of geologic features of greatest interest and meet complementary needs related to geologic mapping, mineral resource research,
and mapping of Quaternary faults.
The effort is focused on the areas encompassing and surrounding the Oregon Trail Structural Belt, which may represent the largely obscured boundary between the Beartooth-Bighorn
magmatic zone and the southern accreted terranes. This region contains several known and suspected mineral systems of high interest for their critical mineral potential, and has
been the subject of abundant past and current exploration and mining.
The area covers the South Pass-Atlantic City region, Rattlesnake Hills, Granite Mountains, and the Seminoe-Ferris mountains. Additionally, the airborne survey data are expected to
aid in mapping and investigations along the North and South Granite Mountains faults, the Continental Fault, and other suspected Quaternary faults. The planned survey includes
magnetic and radiometric data collected from a helicopter along flight lines spaced 200 meters and a nominal terrain clearance of 100 meters.
The mineral systems of interest in the survey area include alkalic porphyry, mafic magmatic, magmatic REE, metamorphic graphite, meteoric convection, orogenic gold, porphyry Cu-Mo-Au,
and volcanogenic seafloor. Potential critical mineral commodities: aluminum, antimony, arsenic, barium, beryllium, bismuth, cobalt, chromium, fluorspar, gallium, germanium, graphite,
hafnium, indium, manganese, niobium, nickel, platinum group elements, rare earth elements, scandium, tantalum, tin, tungsten, vanadium, zinc, and zirconium. There is additional
potential for cadmium, copper, gold, iron, lead, mercury, molybdenum, phosphorus, selenium, silver, thorium, and yttrium.
Central Laramie Mountains
The WSGS is conducting ongoing geochemical, geochronological, and petrographic analyses in the central Laramie Mountains. This work is a continuation of extensive investigation of the
critical mineral potential of this part of the southeast Wyoming that was conducted through the USGS Earth MRI program, which resulted in the publication of
RI-79, and the
King Mountain and
Ragged Top 7.5-minute quadrangles.
The project area encompasses the Laramie Anorthosite Complex, which has potential for rare earth elements and other critical mineral
resources (titanium, vanadium, chromium, nickel). The area also contains multiple greenstone belts, including the Elmers Rock Greenstone Belt, which consist of intensely deformed
metasedimentary and metavolcanic rocks that that have been intruded by the Kennedy dike swarm. Komatiitic metabasalts, peridotite dikes, and altered ultramafic rocks are potential
sources of nickel, chromium, cobalt, vanadium, and platinum group elements. Graphitic schists are also common throughout the greenstone belts, including the Rabbit Creek graphite
deposit in Platte County. The study area also contains the Iron Mountain kimberlite district, which intruded into the Mule Creek lobe of the Sherman batholith. Polymetallic deposits
bearing a variety of base and precious metals (copper, gold, silver, molybdenum) and critical minerals (tungsten, tin, nickel, zinc, antimony, palladium, bismuth, barium) are found
in the southern part of the study area, but their extent and affinity are not well defined.
Water
Tensleep Sandstone Aquifer
WSGS hydrology staff have embarked on a compilation project focused on the Tensleep Sandstone aquifer—an important aquifer in Wyoming.
“One of the goals of this project is to gather in one place what is known about the Tensleep aquifer,” says WSGS hydrogeologist, Kurt Hinaman.
The Tensleep and its equivalent geologic formations occur statewide east of the Overthrust Belt and the Absaroka Range. They supply drinking and stock water along many basin
margins in Wyoming. Additionally, the Tensleep is a reservoir for oil, and is one of the target aquifers in deep basins for the sequestration of carbon dioxide.
Data about the Tensleep aquifer that will be covered in the publication include groundwater quality, porosity, permeability, surface recharge, oil field water injection, and oil field water production.
Mapping
STATEMAP Projects
Geologists at the Wyoming State Geological Survey (WSGS) are working on a pair of 1:100,000-scale geologic maps through the U.S.
National Cooperative Geologic Mapping Program (STATEMAP) managed by the U.S. Geological Survey.
Fiscal Year 2022 projects:
- 1:100,000-scale surficial geologic map of the west half of The Ramshorn 30' x 60' quadrangle, Fremont and Park counties
- 1:100,000-scale bedrock geologic map of the Firehole Canyon 30' x 60' quadrangle, Sweetwater County, Wyoming; Daggett County, Utah; and Moffat County, Colorado
The Ramshorn quadrangle encompasses portions of the northern Wind River Range, northwestern Wind River Basin, and southern Absaroka Range. Generating data about
landslides is one goal of the project. The quadrangle is in one of the most landslide-prone regions in the state; U.S. Highway 26/287 runs through the quadrangle
and has been damaged by unstable slopes in recent times. The project will also provide detailed mapping of glacial, alluvial, and other surficial deposits that will
contribute to understanding the regional Quaternary geologic history.
The Firehole Canyon map will be a compilation of the quadrangle’s bedrock geology. The project requires compiling previously published maps and converting more detailed
mapping to a 1:100,000 scale.
The map will provide geologic data relevant to the economic resources within the southern Greater Green River Basin.
Three Surficial Maps of Quads in Central Wyoming Underway
The WSGS is completing 1:100,000-scale surficial maps for the Riverton, Thermopolis, and Carter Mountain quadrangles in central Wyoming. Carter Mountain,
and portions of the Thermopolis and Riverton quadrangles, were mapped previously by James Case and Laura Hallberg. Staff geologists are working to fill in
unmapped areas based on available photography and elevation models.
Publication of the maps will continue the WSGS initiative to complete 1:100,000-scale surficial mapping across Wyoming.
Online Map on Mineral Resources in the State Under Development
Wyoming is rich with minerals. A new interactive map under development at the WSGS will serve as a central location to find and research relevant mineral and
mining information from both state and federal agencies, as well as host data collected by the WSGS for mineral-related publications.
The new product will revamp and expand the Survey’s 2018 Mines and Minerals Map. For example, the new map will offer data from the U.S. Geological Survey, such as the Topographic
Mine and Prospect and Coal Quality databases, as well as the Wilderness Area Mineral Resource reports.
Several static WSGS maps that have been made interactive will be included as well, and there will be a series of layers showing study areas for WSGS publications.
Helium
Helium Resources in Wyoming
The United States is the largest producer of helium, and is a net exporter. Wyoming has the largest helium reserves in the country. A new project underway at the WSGS focuses on Wyoming’s
helium resources. Specifically, geoscientists will digitize existing data on helium resources to make it more accessible and incorporate updated information.
The U.S. Geological Survey estimates there are 148 billion cubic feet of recoverable helium from known natural gas reservoirs in the Rocky Mountain region, most of which is in Wyoming.
Currently, helium is recovered from deep wells in association with natural gas and carbon dioxide at the Labarge-Shute Creek treating facility in Lincoln County.