Cal Ruleman
Research Geologist constructing geologic maps and performing research related to our Nation's natural resources and hazards
Current Research:
Neotectonics and Structural Evolution of Intermountain Western North America
Geomorphic and Hydrologic Evolution of Plio-Pleistocene Fluvial Systems and Chronostratigraphy of Western North America
Geomorphology and Chronology of North American Pleistocene Glacial-Periglacial Systems
Geologic and Geomorphic History of Contaminants in Western North American River Systems
Professional Experience
2007-Present: Research Geologist, USGS
2004-2007: Geologist, USGS contractor and private sector
2002-2004: U.S. Peace Corp Volunteer, Suriname, South America
2000-2002: USGS student intern
Education and Certifications
1999: B.A., University of Montana, Missoula
2002: M.S., Montana State University, Bozeman
Affiliations and Memberships*
1996-Present: Geological Society of America
2000-Present: Colorado Scientific Society
Science and Products
Clumped isotopes record a glacial-interglacial shift in seasonality of soil carbonate accumulation in the San Luis Valley, southern Rocky Mountains, USA
The Seamless Integrated Geologic Mapping (SIGMa) extension to the Geologic Map Schema (GeMS)
Geologic map of the Mount Blue Sky (formerly Mount Evans) quadrangle, Clear Creek and Park Counties, Colorado
Early Pleistocene climate-induced erosion of the Alaska Range formed the Nenana Gravel
Assessing geohazards to the Denali National Park road with geologic mapping
Middle Pleistocene formation of the Rio Grande Gorge, San Luis Valley, south-central Colorado and north-central New Mexico, USA: Process, timing, and downstream implications
Establishing chronologies for alluvial-fan sequences with analysis of high-resolution topographic data: San Luis Valley, Colorado, USA
Geophysical expression of buried range-front embayment structure: Great Sand Dunes National Park, Rio Grande rift, Colorado
Geomorphic evolution of the San Luis Basin and Rio Grande in southern Colorado and northern New Mexico
Neotectonics and geomorphic evolution of the northwestern arm of the Yellowstone Tectonic Parabola: Controls on intra-cratonic extensional regimes, southwest Montana
Identifying buried segments of active faults in the northern Rio Grande Rift using aeromagnetic, LiDAR,and gravity data, south-central Colorado, USA
Late Miocene-Pleistocene evolution of a Rio Grande rift subbasin, Sunshine Valley-Costilla Plain, San Luis Basin, New Mexico and Colorado
Surficial Working Group
Denali National Park Geohazards Geologic Mapping
Geologic Framework of the Intermountain West
Surficial geologic map database for the Blanca Peak, Walsenburg, Trinidad, and Alamosa 30' x 60' quadrangles, Colorado
Data Release for Surficial Geology and Quaternary Tectonics of the Madison Valley and Fault Zone, Madison, Gallatin, and Beaverhead Counties, southwest Montana
Cosmogenic Al-26/Be-10 Isochron Burial Data for the Nussbaum Gravel at Baculite Mesa, CO
Surficial geologic map database of the Aztec 1-degree by 2-degree quadrangle, northern New Mexico and southern Colorado: Contributions to the National Geologic Map
Surficial geologic map database of the Durango 1-degree by 2-degree quadrangle, southern Colorado: Contributions to the National Geologic Map
Data release for Geologic Map of the Homestake Reservoir 7.5' quadrangle, Lake, Pitkin, and Eagle Counties, Colorado
Data release for Middle Pleistocene formation of the Rio Grande Gorge, San Luis Valley, south-central Colorado and north-central New Mexico, USA: Process, timing, and downstream implications
Data Release for Geologic Map of the Leadville North 7.5' Quadrangle, Eagle and Lake Counties, Colorado
Surficial geology of the northern San Luis Valley, Saguache, Fremont, Custer, Alamosa, Rio Grande, Conejos, and Costilla Counties, Colorado
Geologic map of the Homestake Reservoir 7.5′ quadrangle, Lake, Pitkin, and Eagle Counties, Colorado
Geologic map of the Poncha Pass area, Chaffee, Fremont, and Saguache Counties, Colorado
Geologic map of the Leadville North 7.5’ quadrangle, Eagle and Lake Counties, Colorado
Geologic map of the upper Arkansas River valley region, north-central Colorado
Geologic map of the Bailey 30' x 60' quadrangle, North-Central Colorado
Geologic Map of the Sulphur Mountain Quadrangle, Park County, Colorado
Geologic Map of the Elkhorn Quadrangle, Park County, Colorado
Science and Products
Clumped isotopes record a glacial-interglacial shift in seasonality of soil carbonate accumulation in the San Luis Valley, southern Rocky Mountains, USA
The Seamless Integrated Geologic Mapping (SIGMa) extension to the Geologic Map Schema (GeMS)
Geologic map of the Mount Blue Sky (formerly Mount Evans) quadrangle, Clear Creek and Park Counties, Colorado
Early Pleistocene climate-induced erosion of the Alaska Range formed the Nenana Gravel
Assessing geohazards to the Denali National Park road with geologic mapping
Middle Pleistocene formation of the Rio Grande Gorge, San Luis Valley, south-central Colorado and north-central New Mexico, USA: Process, timing, and downstream implications
Establishing chronologies for alluvial-fan sequences with analysis of high-resolution topographic data: San Luis Valley, Colorado, USA
Geophysical expression of buried range-front embayment structure: Great Sand Dunes National Park, Rio Grande rift, Colorado
Geomorphic evolution of the San Luis Basin and Rio Grande in southern Colorado and northern New Mexico
Neotectonics and geomorphic evolution of the northwestern arm of the Yellowstone Tectonic Parabola: Controls on intra-cratonic extensional regimes, southwest Montana
Identifying buried segments of active faults in the northern Rio Grande Rift using aeromagnetic, LiDAR,and gravity data, south-central Colorado, USA
Late Miocene-Pleistocene evolution of a Rio Grande rift subbasin, Sunshine Valley-Costilla Plain, San Luis Basin, New Mexico and Colorado
Surficial Working Group
Denali National Park Geohazards Geologic Mapping
Geologic Framework of the Intermountain West
Surficial geologic map database for the Blanca Peak, Walsenburg, Trinidad, and Alamosa 30' x 60' quadrangles, Colorado
Data Release for Surficial Geology and Quaternary Tectonics of the Madison Valley and Fault Zone, Madison, Gallatin, and Beaverhead Counties, southwest Montana
Cosmogenic Al-26/Be-10 Isochron Burial Data for the Nussbaum Gravel at Baculite Mesa, CO
Surficial geologic map database of the Aztec 1-degree by 2-degree quadrangle, northern New Mexico and southern Colorado: Contributions to the National Geologic Map
Surficial geologic map database of the Durango 1-degree by 2-degree quadrangle, southern Colorado: Contributions to the National Geologic Map
Data release for Geologic Map of the Homestake Reservoir 7.5' quadrangle, Lake, Pitkin, and Eagle Counties, Colorado
Data release for Middle Pleistocene formation of the Rio Grande Gorge, San Luis Valley, south-central Colorado and north-central New Mexico, USA: Process, timing, and downstream implications
Data Release for Geologic Map of the Leadville North 7.5' Quadrangle, Eagle and Lake Counties, Colorado
Surficial geology of the northern San Luis Valley, Saguache, Fremont, Custer, Alamosa, Rio Grande, Conejos, and Costilla Counties, Colorado
Geologic map of the Homestake Reservoir 7.5′ quadrangle, Lake, Pitkin, and Eagle Counties, Colorado
Geologic map of the Poncha Pass area, Chaffee, Fremont, and Saguache Counties, Colorado
Geologic map of the Leadville North 7.5’ quadrangle, Eagle and Lake Counties, Colorado
Geologic map of the upper Arkansas River valley region, north-central Colorado
Geologic map of the Bailey 30' x 60' quadrangle, North-Central Colorado
Geologic Map of the Sulphur Mountain Quadrangle, Park County, Colorado
Geologic Map of the Elkhorn Quadrangle, Park County, Colorado
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government