Research Geologist Adam Hudson installs a soil temperature and moisture monitoring station for a topographic asymmetry study in the Great Sand Dunes National Park and Preserve (Sangre de Cristo Mountains, Colorado, USA).
Geologic Framework of the Intermountain West Active
The Geologic Framework of the Intermountain West (IMW) Project is creating a seamless, integrated, geologic map database that spans the Intermountain West region. The database will serve enhanced geologic map data to support geoscience research, environmental and resource assessments, and the communication of geologic information for all U.S. Geological Survey stakeholders.
This innovative approach to serving geologic map data synthesizes new and existing geologic mapping into a spatially consistent geologic framework, preserves source metadata, and improves the queryability of map unit information. The stratigraphic framework that underpins the geologic mapping is constructed dynamically using a process-based, time-dependent, hierarchical classification of map units. This data set can be integrated with users’ data via GIS hosted feature layers or can be viewed using the Intermountain West Geologic Map Explorer .
Research groups within this project investigate the magmatic, tectonic, stratigraphic, and landscape evolution of the Intermountain West through targeted studies of geologic processes.
The Intermountain West Seamless Geologic Map Explorer is now live!
The USGS Geochron Database Explorer is now live!
Data release of zircon U-Pb geochronology and whole-rock isotope geochemistry for drill core samples from Montana, Nebraska, Nevada, and Wyoming
Detrital zircon U-Pb data for Upper Triassic sandstones of the Auld Lang Syne basin, northwest Nevada, USA
Seamless Integrated Geologic Map Database of the Intermountain West: Contributions to The National Geologic Map
Data release of isotope geochemistry, mineral chemistry, and geochronology for a Proterozoic paragneiss sampled from drill core from North Dakota
Data release of monazite and xenotime geochronology for Proterozoic rocks in central Colorado and monazite and zircon geochronology and whole-rock isotope geochemistry fo a Proterozoic drill core sample from western Colorado
U-Pb detrital zircon data and Ar feldspar data from middle Cenozoic sandstones and volcanic tuffs from southern Nevada, USA
Maximum horizontal stress orientation and relative stress magnitude (faulting regime) data throughout North America
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
Zircon U-Pb geochronology and whole rock geochemistry for pre-ignimbrite volcanoes within the San Juan locus of the mid-Cenozoic Southern Rocky Mountain volcanic field, Colorado
Surficial geologic map database of the Durango 1-degree by 2-degree quadrangle, southern Colorado: Contributions to the National Geologic Map
Geochronologic and isotopic data for Paleohydrologic history of Pluvial Lake San Agustin, New Mexico
Data Release of Geochemical, Geochronologic, and Isotopic Data for Precambrian to Cenozoic Rocks from Colorado, New Mexico, Utah, and Wyoming
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 Bonanza caldera area, northeastern San Juan Mountains, Colorado
Geologic map of Petroglyph National Monument and vicinity, Bernalillo County, New Mexico
Geologic map of the San Antonio Mountain area, northern New Mexico and southern Colorado
Research Geologist Adam Hudson installs a soil temperature and moisture monitoring station for a topographic asymmetry study in the Great Sand Dunes National Park and Preserve (Sangre de Cristo Mountains, Colorado, USA).
Research Geologist Amy Gilmer walks over carbonate rocks of the Upper Triassic Star Peak Group (northern Humboldt Range, Nevada, USA).
Research Geologist Amy Gilmer walks over carbonate rocks of the Upper Triassic Star Peak Group (northern Humboldt Range, Nevada, USA).
Geologic Framework of the Intermountain West project members Adam Hudson, Margaret Berry, Harrison Gray, Cal Ruleman, and Samuel Johnstone perform field work for a topographic asymmetry study in the Great Sand Dunes National Park and Preserve (Sangre de Cristo Mountains, Colorado, USA).
Geologic Framework of the Intermountain West project members Adam Hudson, Margaret Berry, Harrison Gray, Cal Ruleman, and Samuel Johnstone perform field work for a topographic asymmetry study in the Great Sand Dunes National Park and Preserve (Sangre de Cristo Mountains, Colorado, USA).
In an effort to better understand the effects of abandoned mine lands on natural resources, Research Geologists Margaret Berry and Adam Hudson collect samples of ancestral Animas River sediment for geochemical analysis (Durango, Colorado, USA).
In an effort to better understand the effects of abandoned mine lands on natural resources, Research Geologists Margaret Berry and Adam Hudson collect samples of ancestral Animas River sediment for geochemical analysis (Durango, Colorado, USA).
Gravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National Park
linkIntermountain West Project members Adam Hudson and Michael Frothingham, in collaboration with National Park Service archaeologist Patrick Fristoe, inspect gravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National Park (Alaska, USA).
Gravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National Park
linkIntermountain West Project members Adam Hudson and Michael Frothingham, in collaboration with National Park Service archaeologist Patrick Fristoe, inspect gravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National Park (Alaska, USA).
Wild burros stand guard on the path to Miocene volcaniclastic rocks of the Death Valley region (California, USA).
Wild burros stand guard on the path to Miocene volcaniclastic rocks of the Death Valley region (California, USA).
Research Geologist Jens-Erik Lundstern poses as a scale for middle Cenozoic fluvial conglomerates in the Delamar Mountains (southern Nevada, USA).
Research Geologist Jens-Erik Lundstern poses as a scale for middle Cenozoic fluvial conglomerates in the Delamar Mountains (southern Nevada, USA).
Research Geologist Jens-Erik Lundstern explores multi-colored lacustrine shales of the Oligocene Amargosa Valley Formation (Bat Mountain, California, USA).
Research Geologist Jens-Erik Lundstern explores multi-colored lacustrine shales of the Oligocene Amargosa Valley Formation (Bat Mountain, California, USA).
Research Geologist Theresa Schwartz takes field notes about the Cenozoic sedimentary rocks of Bat Mountain (Death Valley region, California, USA).
Research Geologist Theresa Schwartz takes field notes about the Cenozoic sedimentary rocks of Bat Mountain (Death Valley region, California, USA).
Research Geologist Theresa Schwartz walks over Cenozoic sedimentary rocks in Death Valley National Park (California, USA).
Research Geologist Theresa Schwartz walks over Cenozoic sedimentary rocks in Death Valley National Park (California, USA).
The flat-lying rhyolite of Cropsy Mountain overlies the hydrothermally altered Summitville Andesite (San Juan Mountains, Colorado, USA).
The flat-lying rhyolite of Cropsy Mountain overlies the hydrothermally altered Summitville Andesite (San Juan Mountains, Colorado, USA).
Sunset view across Little Molas Lake, an alpine glacial lake on the west side of the Animas River Valley (San Juan Mountains, Colorado, USA).
Sunset view across Little Molas Lake, an alpine glacial lake on the west side of the Animas River Valley (San Juan Mountains, Colorado, USA).
Geologist Alexander Lusk investigates slickenlines on the Moab fault near Arches National Park (Utah, USA).
Geologist Alexander Lusk investigates slickenlines on the Moab fault near Arches National Park (Utah, USA).
Intermountain West Project members Theresa Schwartz and Alexander Lusk investigate the Pennsylvanian Honaker Trail Formation at Goosenecks State Park (Utah, USA).
Intermountain West Project members Theresa Schwartz and Alexander Lusk investigate the Pennsylvanian Honaker Trail Formation at Goosenecks State Park (Utah, USA).
Intermountain West Project members discuss an outcrop of the Oligocene-Miocene Troublesome Formation (near Kremmling, Colorado, USA).
Intermountain West Project members discuss an outcrop of the Oligocene-Miocene Troublesome Formation (near Kremmling, Colorado, USA).
Red sedimentary rocks of the Pennsylvanian-Permian Maroon Formation exposed on Avery Peak dip southwestward away from gray igneous rocks of the Cenozoic White Rock pluton.
Red sedimentary rocks of the Pennsylvanian-Permian Maroon Formation exposed on Avery Peak dip southwestward away from gray igneous rocks of the Cenozoic White Rock pluton.
Intermountain West Project members pose at the summit of Crested Butte (Colorado, USA) prior to examining the Crested Butte laccolith (from left to right, Jeremy Workman, Allison Dombrowski, Ian Hillenbrand, Amy Gilmer, Kenzie Turner, and Ren Thompson).
Intermountain West Project members pose at the summit of Crested Butte (Colorado, USA) prior to examining the Crested Butte laccolith (from left to right, Jeremy Workman, Allison Dombrowski, Ian Hillenbrand, Amy Gilmer, Kenzie Turner, and Ren Thompson).
A view westward from Cottonwood Pass (Sawatch Range, Colorado, USA) into the Taylor Park basin. The peaks in the backgorund are composed of igneous and metamorphic rocks ranging in age from early Paleozoic to Eocene, uplifted along the Taylor Park fault.
A view westward from Cottonwood Pass (Sawatch Range, Colorado, USA) into the Taylor Park basin. The peaks in the backgorund are composed of igneous and metamorphic rocks ranging in age from early Paleozoic to Eocene, uplifted along the Taylor Park fault.
Vivid red, orange, and yellow colors highlight hydrothermally altered rocks on East Red Mountain in the Grizzly Peak caldera (Sawatch Range, Colorado, USA).
Vivid red, orange, and yellow colors highlight hydrothermally altered rocks on East Red Mountain in the Grizzly Peak caldera (Sawatch Range, Colorado, USA).
Geologist Michael Frothingham observes strongly deformed rocks of a Proterozoic shear zone in the Medicine Bow Mountains (Wyoming, USA).
Geologist Michael Frothingham observes strongly deformed rocks of a Proterozoic shear zone in the Medicine Bow Mountains (Wyoming, USA).
Below are publications associated with the Geologic Framework of the Intermountain West Project.
Late Triassic paleogeography of southern Laurentia and its fringing arcs: Insights from detrital zircon U-Pb geochronology and Hf isotope geochemistry, Auld Lang Syne basin (Nevada, USA)
Paleogene sedimentary basin development in southern Nevada, USA
Paleoproterozoic reworking of Archean crust and extreme back-arc metamorphism in the enigmatic southern Trans-Hudson orogen
Heterogeneous multi-stage accretionary orogenesis — Evidence from the Gunnison block in the Yavapai Province, southwest USA
The importance of nodal plane orientation diversity for earthquake focal mechanism stress inversions
Geochemical evidence for evolving Proterozoic crustal thickness and orogenic styles in southwestern Laurentia
Fluorine-rich mafic lower crust in the southern Rocky Mountains: The role of pre-enrichment in generating fluorine-rich silicic magmas and porphyry Mo deposits
Triple oxygen isotope compositions of globally distributed soil carbonates record widespread evaporation of soil waters
Monazite and xenotime petrochronologic constraints on four Proterozoic tectonic episodes and ca. 1705 Ma age of the Uncompahgre Formation, southwestern Colorado, USA
Paleohydrologic history of pluvial lake San Agustin, New Mexico: Tracking changing effective moisture in southwest North America through the last glacial transition
Revised age and regional correlations of Cenozoic strata on Bat Mountain, Death Valley region, California, USA, from zircon U-Pb geochronology of sandstones and ash-fall tuffs
Insights from the Alabama Hills into Mesozoic magmatism and tectonics in eastern California
Intermountain West Seamless Geologic Map Explorer
The Intermountain West Seamless Geologic Map Explorer is an interactive mapping application that hosts surficial and bedrock geologic data layers for a transect from the Rio Grande rift to the Basin and Range.
USGS Geochron Database Explorer
This Web Application is a tool for viewing, exploring, and downloading the "USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data" Data Release.
- Overview
The Geologic Framework of the Intermountain West (IMW) Project is creating a seamless, integrated, geologic map database that spans the Intermountain West region. The database will serve enhanced geologic map data to support geoscience research, environmental and resource assessments, and the communication of geologic information for all U.S. Geological Survey stakeholders.
This innovative approach to serving geologic map data synthesizes new and existing geologic mapping into a spatially consistent geologic framework, preserves source metadata, and improves the queryability of map unit information. The stratigraphic framework that underpins the geologic mapping is constructed dynamically using a process-based, time-dependent, hierarchical classification of map units. This data set can be integrated with users’ data via GIS hosted feature layers or can be viewed using the Intermountain West Geologic Map Explorer .
Research groups within this project investigate the magmatic, tectonic, stratigraphic, and landscape evolution of the Intermountain West through targeted studies of geologic processes.
The Intermountain West Seamless Geologic Map Explorer is now live!The Intermountain West Seamless Geologic Map Explorer is now live!The USGS Geochron Database Explorer is now live!The USGS Geochron Database Explorer is now live! - Data
Filter Total Items: 29
Data release of zircon U-Pb geochronology and whole-rock isotope geochemistry for drill core samples from Montana, Nebraska, Nevada, and Wyoming
This U.S. Geological Survey (USGS) data release provides zircon U-Pb geochronology and whole rock isotope geochemistry for drill core samples from Montana, Nebraska, Nevada and Wyoming. The drill core samples were obtained from the USGS Core Research Center in Denver, Colorado. The samples were in order to constrain the age, provenance, metamorphic history, and geochemical character of basement teDetrital zircon U-Pb data for Upper Triassic sandstones of the Auld Lang Syne basin, northwest Nevada, USA
This data release includes raw detrital zircon U-Pb data for isolated sandstones in Upper Triassic deposits of the Auld Lang Syne basin of northwest Nevada, USA. Detrital zircon U-Pb data for 11 sandstone samples (3269 zircon U-Pb dates) were acquired via LA-ICP-MS at the University of Arizona LaserChron Center for 11 sandstone samples. Primary insights from the data are twofold: 1) The data proviSeamless Integrated Geologic Map Database of the Intermountain West: Contributions to The National Geologic Map
This dataset is intended to provide seamless, integrated geologic mapping of the U.S. Intermountain West region as a contribution to The National Geologic Map supported by the National Cooperative Geologic Mapping Program of the U.S. Geological Survey. Surficial and bedrock geology are included in this data release as independent datasets at a variable resolution from 1:50,000 to 1:250,000 scale.Data release of isotope geochemistry, mineral chemistry, and geochronology for a Proterozoic paragneiss sampled from drill core from North Dakota
This U.S. Geological Survey (USGS) data release provides whole rock isotope geochemistry, zircon hafnium isotope geochemistry, feldspar mineral chemistry, and zircon, monazite, and xenotime geochronology for a paragneiss sampled from a drill core from North Dakota. The sample was collected from the 9-11R E-M Larson well in order to constrain the depositional age, provenance, metamorphic history, aData release of monazite and xenotime geochronology for Proterozoic rocks in central Colorado and monazite and zircon geochronology and whole-rock isotope geochemistry fo a Proterozoic drill core sample from western Colorado
This U.S. Geological Survey (USGS) data release provides monazite and xenotime geochronology from Proterozoic rocks collected from outcrop in central Colorado and whole rock isotope geochemistry, and zircon and monazite geochronology from a Proterozoic rock sampled from a drill core from western Colorado. The drill core sample was collected from the 1 Paradox Valley injection core near Bedrock, COU-Pb detrital zircon data and Ar feldspar data from middle Cenozoic sandstones and volcanic tuffs from southern Nevada, USA
This Data Release accompanies the planned publication, "Paleogene sedimentary basin development in southern Nevada, USA." Included here are U-Pb detrital zircon and Ar/Ar feldspar geochronologic data for middle Cenozoic sedimentary and volcanic rocks collected by Jens-Erik Lundstern and Theresa M. Schwartz in several parts of southern Nevada, U.S. The target strata are the lowest Cenozoic sedimentMaximum horizontal stress orientation and relative stress magnitude (faulting regime) data throughout North America
This Data Release accompanies the publication "State of stress in areas of active unconventional oil and gas development in North America" by J.-E. Lund Snee (now J.-E. Lundstern) and M.D. Zoback (2022) in the AAPG Bulletin. This dataset provides maximum horizontal stress (SHmax) orientation and relative stress magnitude (faulting regime) information that comprise a new-generation crustal stress mSurficial geologic map database of the Aztec 1-degree by 2-degree quadrangle, northern New Mexico and southern Colorado: Contributions to the National Geologic Map
This data release presents geologic map data for the surficial geology of the Aztec 1-degree by 2-degree quadrangle. The map area lies within two physiographic provinces of Fenneman (1928): the Southern Rocky Mountains province, and the Colorado Plateau province, Navajo section. Geologic mapping is mostly compiled from published geologic map data sources ranging from 1:24,000 to 1:250,000 scale, wZircon U-Pb geochronology and whole rock geochemistry for pre-ignimbrite volcanoes within the San Juan locus of the mid-Cenozoic Southern Rocky Mountain volcanic field, Colorado
This U.S. Geological Survey (USGS) data release provides whole rock major, minor, and trace element geochemical data and zircon U-Pb geochronology and trace element concentrations for samples from pre-ignimbrite volcanoes within the San Juan locus of the mid-Cenozoic Southern Rocky Mountain volcanic field, Colorado. Samples were collected in order to constrain the evolution of the pre-ignimbrite mSurficial geologic map database of the Durango 1-degree by 2-degree quadrangle, southern Colorado: Contributions to the National Geologic Map
This data release presents geologic map data for the surficial geology of the Durango 1-degree by 2-degree quadrangle and adjacent areas along the northern boundary of the quadrangle. The map area lies within two physiographic provinces of Fenneman (1928): the Southern Rocky Mountains province, and the Colorado Plateau province, Navajo section. Geologic mapping is mostly compiled from published geGeochronologic and isotopic data for Paleohydrologic history of Pluvial Lake San Agustin, New Mexico
This dataset includes tables of radiocarbon, uranium thorium series, and luminescence geochronologic ages and stable carbon and oxygen isotope compositions for sedimentary and organic samples.Data Release of Geochemical, Geochronologic, and Isotopic Data for Precambrian to Cenozoic Rocks from Colorado, New Mexico, Utah, and Wyoming
This U.S. Geological Survey (USGS) data release includes whole rock geochemical and isotopic data, and uranium-lead isotopic data collected by both Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and Sensitive High Resolution Ion Microprobe-Reverse Geometry (SHRIMP-RG) methods for rocks in Colorado, Wyoming, Utah, and New Mexico. - Maps
Surficial geology of the northern San Luis Valley, Saguache, Fremont, Custer, Alamosa, Rio Grande, Conejos, and Costilla Counties, Colorado
The San Luis Valley and associated underlying basin of south-central Colorado and north-central New Mexico is the largest structural and hydrologic basin of the Rio Grande Rift and fluvial system. The surrounding San Juan and Sangre de Cristo Mountains reveal evidence of widespread volcanism and transtensional tectonism beginning in the Oligocene and continuing to the present, as seen in fault diGeologic map of the Homestake Reservoir 7.5′ quadrangle, Lake, Pitkin, and Eagle Counties, Colorado
The Homestake Reservoir 7.5' quadrangle lies at the northwestern end of the Upper Arkansas Valley, and headwaters of the Arkansas River, and the Roaring Fork, Fryingpan, and Eagle Rivers of the Colorado River system. The quadrangle lies within tectonic provinces of the 1.4 giga-annum (Ga) Picuris orogeny and includes the late Paleozoic Ancestral Rockies, Late Cretaceous-Paleocene Laramide orogenyGeologic map of the Bonanza caldera area, northeastern San Juan Mountains, Colorado
The San Juan Mountains in southwestern Colorado have long been known as a site of exceptionally voluminous mid-Tertiary volcanism, including at least 22 major ignimbrite sheets (each 150–5,000 km³) and associated caldera structures active at 34–23 Ma. Recent volcanologic and petrologic studies in the San Juan region have focused mainly on several ignimbrite-caldera systems: the southeastern area (Geologic map of Petroglyph National Monument and vicinity, Bernalillo County, New Mexico
This geologic map depicts and briefly describes geologic units underlying Petroglyph National Monument and immediately adjacent areas in Bernalillo County, New Mexico. The Monument is underlain dominantly by Quaternary basalts of the Albuquerque Volcanoes volcanic field, a series of basin-filling volcanic flows and associated vents from a monogenetic volcanic highland along the eastern margin of tGeologic map of the San Antonio Mountain area, northern New Mexico and southern Colorado
The geologic map of the San Antonio Mountain area in northern New Mexico and southern Colorado is located along the west-central part of the San Luis Valley. The San Luis Valley is the geomorphic expression of the San Luis Basin, an extensional basin associated with the northern Rio Grande rift. Deposits within the map area record volcanic, sedimentary, and tectonic processes over the last ~33 mil - Multimedia
Installing a soil temperature and moisture monitoring stationInstalling a soil temperature and moisture monitoring station
Research Geologist Adam Hudson installs a soil temperature and moisture monitoring station for a topographic asymmetry study in the Great Sand Dunes National Park and Preserve (Sangre de Cristo Mountains, Colorado, USA).
Research Geologist Adam Hudson installs a soil temperature and moisture monitoring station for a topographic asymmetry study in the Great Sand Dunes National Park and Preserve (Sangre de Cristo Mountains, Colorado, USA).
Carbonate rocks, northern Humboldt Range, NevadaResearch Geologist Amy Gilmer walks over carbonate rocks of the Upper Triassic Star Peak Group (northern Humboldt Range, Nevada, USA).
Research Geologist Amy Gilmer walks over carbonate rocks of the Upper Triassic Star Peak Group (northern Humboldt Range, Nevada, USA).
Geologic Framework of the Intermountain West Project membersGeologic Framework of the Intermountain West Project membersGeologic Framework of the Intermountain West project members Adam Hudson, Margaret Berry, Harrison Gray, Cal Ruleman, and Samuel Johnstone perform field work for a topographic asymmetry study in the Great Sand Dunes National Park and Preserve (Sangre de Cristo Mountains, Colorado, USA).
Geologic Framework of the Intermountain West project members Adam Hudson, Margaret Berry, Harrison Gray, Cal Ruleman, and Samuel Johnstone perform field work for a topographic asymmetry study in the Great Sand Dunes National Park and Preserve (Sangre de Cristo Mountains, Colorado, USA).
Collecting sediment for geochemical analysisIn an effort to better understand the effects of abandoned mine lands on natural resources, Research Geologists Margaret Berry and Adam Hudson collect samples of ancestral Animas River sediment for geochemical analysis (Durango, Colorado, USA).
In an effort to better understand the effects of abandoned mine lands on natural resources, Research Geologists Margaret Berry and Adam Hudson collect samples of ancestral Animas River sediment for geochemical analysis (Durango, Colorado, USA).
Gravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National ParkGravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National ParkGravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National Park
linkIntermountain West Project members Adam Hudson and Michael Frothingham, in collaboration with National Park Service archaeologist Patrick Fristoe, inspect gravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National Park (Alaska, USA).
Gravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National Park
linkIntermountain West Project members Adam Hudson and Michael Frothingham, in collaboration with National Park Service archaeologist Patrick Fristoe, inspect gravel deposits and associated geologic hazards along the Hines Creek fault system, Denali National Park (Alaska, USA).
Wild burrosWild burros stand guard on the path to Miocene volcaniclastic rocks of the Death Valley region (California, USA).
Wild burros stand guard on the path to Miocene volcaniclastic rocks of the Death Valley region (California, USA).
Cenozoic fluvial conglomerates in the Delamar Mountains, NevadaCenozoic fluvial conglomerates in the Delamar Mountains, NevadaResearch Geologist Jens-Erik Lundstern poses as a scale for middle Cenozoic fluvial conglomerates in the Delamar Mountains (southern Nevada, USA).
Research Geologist Jens-Erik Lundstern poses as a scale for middle Cenozoic fluvial conglomerates in the Delamar Mountains (southern Nevada, USA).
Multi-colored lacustrine shales of the Oligocene Amargosa Valley FormationMulti-colored lacustrine shales of the Oligocene Amargosa Valley FormationResearch Geologist Jens-Erik Lundstern explores multi-colored lacustrine shales of the Oligocene Amargosa Valley Formation (Bat Mountain, California, USA).
Research Geologist Jens-Erik Lundstern explores multi-colored lacustrine shales of the Oligocene Amargosa Valley Formation (Bat Mountain, California, USA).
Cenozoic sedimentary rocks of Bat MountainResearch Geologist Theresa Schwartz takes field notes about the Cenozoic sedimentary rocks of Bat Mountain (Death Valley region, California, USA).
Research Geologist Theresa Schwartz takes field notes about the Cenozoic sedimentary rocks of Bat Mountain (Death Valley region, California, USA).
Sedimentary rocks in Death Valley National ParkResearch Geologist Theresa Schwartz walks over Cenozoic sedimentary rocks in Death Valley National Park (California, USA).
Research Geologist Theresa Schwartz walks over Cenozoic sedimentary rocks in Death Valley National Park (California, USA).
Cropsy MountainThe flat-lying rhyolite of Cropsy Mountain overlies the hydrothermally altered Summitville Andesite (San Juan Mountains, Colorado, USA).
The flat-lying rhyolite of Cropsy Mountain overlies the hydrothermally altered Summitville Andesite (San Juan Mountains, Colorado, USA).
Sunset at Little Molas Lake, ColoradoSunset view across Little Molas Lake, an alpine glacial lake on the west side of the Animas River Valley (San Juan Mountains, Colorado, USA).
Sunset view across Little Molas Lake, an alpine glacial lake on the west side of the Animas River Valley (San Juan Mountains, Colorado, USA).
Moab fault near Arches National Park, UtahGeologist Alexander Lusk investigates slickenlines on the Moab fault near Arches National Park (Utah, USA).
Geologist Alexander Lusk investigates slickenlines on the Moab fault near Arches National Park (Utah, USA).
Pennsylvanian Honaker Trail Formation at Goosenecks State ParkPennsylvanian Honaker Trail Formation at Goosenecks State ParkIntermountain West Project members Theresa Schwartz and Alexander Lusk investigate the Pennsylvanian Honaker Trail Formation at Goosenecks State Park (Utah, USA).
Intermountain West Project members Theresa Schwartz and Alexander Lusk investigate the Pennsylvanian Honaker Trail Formation at Goosenecks State Park (Utah, USA).
Oligocene-Miocene Troublesome outcropIntermountain West Project members discuss an outcrop of the Oligocene-Miocene Troublesome Formation (near Kremmling, Colorado, USA).
Intermountain West Project members discuss an outcrop of the Oligocene-Miocene Troublesome Formation (near Kremmling, Colorado, USA).
Avery Peak, ColoradoRed sedimentary rocks of the Pennsylvanian-Permian Maroon Formation exposed on Avery Peak dip southwestward away from gray igneous rocks of the Cenozoic White Rock pluton.
Red sedimentary rocks of the Pennsylvanian-Permian Maroon Formation exposed on Avery Peak dip southwestward away from gray igneous rocks of the Cenozoic White Rock pluton.
Geologic Framework of the Intermountain West project membersGeologic Framework of the Intermountain West project membersIntermountain West Project members pose at the summit of Crested Butte (Colorado, USA) prior to examining the Crested Butte laccolith (from left to right, Jeremy Workman, Allison Dombrowski, Ian Hillenbrand, Amy Gilmer, Kenzie Turner, and Ren Thompson).
Intermountain West Project members pose at the summit of Crested Butte (Colorado, USA) prior to examining the Crested Butte laccolith (from left to right, Jeremy Workman, Allison Dombrowski, Ian Hillenbrand, Amy Gilmer, Kenzie Turner, and Ren Thompson).
Cottonwood Pass, ColoradoA view westward from Cottonwood Pass (Sawatch Range, Colorado, USA) into the Taylor Park basin. The peaks in the backgorund are composed of igneous and metamorphic rocks ranging in age from early Paleozoic to Eocene, uplifted along the Taylor Park fault.
A view westward from Cottonwood Pass (Sawatch Range, Colorado, USA) into the Taylor Park basin. The peaks in the backgorund are composed of igneous and metamorphic rocks ranging in age from early Paleozoic to Eocene, uplifted along the Taylor Park fault.
East Red Mountain in the Grizzly Peak caldera, ColoradoEast Red Mountain in the Grizzly Peak caldera, ColoradoVivid red, orange, and yellow colors highlight hydrothermally altered rocks on East Red Mountain in the Grizzly Peak caldera (Sawatch Range, Colorado, USA).
Vivid red, orange, and yellow colors highlight hydrothermally altered rocks on East Red Mountain in the Grizzly Peak caldera (Sawatch Range, Colorado, USA).
Deformed rocks of a Proterozoic shear zoneGeologist Michael Frothingham observes strongly deformed rocks of a Proterozoic shear zone in the Medicine Bow Mountains (Wyoming, USA).
Geologist Michael Frothingham observes strongly deformed rocks of a Proterozoic shear zone in the Medicine Bow Mountains (Wyoming, USA).
- Publications
Below are publications associated with the Geologic Framework of the Intermountain West Project.
Filter Total Items: 37Late Triassic paleogeography of southern Laurentia and its fringing arcs: Insights from detrital zircon U-Pb geochronology and Hf isotope geochemistry, Auld Lang Syne basin (Nevada, USA)
Fluvial strata of the Upper Triassic Chinle Formation and Dockum Group, exposed across the Western Interior of North America, have long been interpreted to record a transcontinental river system that connected the ancestral Ouachita orogen of Texas and Oklahoma, USA, to the Auld Lang Syne basin of northwestern Nevada, USA, its inferred marine terminus. Fluvial strata are well-characterized by exisAuthorsTheresa Maude Schwartz, Sandra J. Wyld, Joseph Colgan, Douglas W. PriharPaleogene sedimentary basin development in southern Nevada, USA
The cause of the transition from Mesozoic and early Cenozoic crustal shortening to later extension in the western United States is debated. In many parts of the extant Sevier hinterland, now the Basin and Range Province, the sedimentary sections that provide the most direct record of that transition remain poorly studied and lack meaningful age control. In this paper, we present field characterizaAuthorsJens-Erik Lundstern, Theresa Maude Schwartz, Cameron Mark Mercer, Joseph Colgan, Jeremiah B. Workman, Leah E. MorganPaleoproterozoic reworking of Archean crust and extreme back-arc metamorphism in the enigmatic southern Trans-Hudson orogen
The crustal evolution of the southernmost ∼2000–1800 Ma Trans-Hudson orogen (THO) is enigmatic due to burial by Phanerozoic sediments. We provide new insights through petrochronologic analysis of a paragneiss drill core sample. Detrital zircon age peaks at 2625, 2340, and 1880 Ma and Hf isotopes suggest Paleoproterozoic arc development proximal to Archean source(s). Phase equilibria modeling and tAuthorsIan William Hillenbrand, Amy K. Gilmer, Michael L. Williams, Amanda (Kate) Souders, Michael J. Jercinovic, Heather A. Lowers, Jorge A. VazquezHeterogeneous multi-stage accretionary orogenesis — Evidence from the Gunnison block in the Yavapai Province, southwest USA
Proterozoic rocks exposed in the southwestern U.S.A. represent one of the best examples of crustal growth by arc-related magmatism and accretionary orogenesis. Within the Southwest the 1.8–1.7 Ga Yavapai Province is widely regarded as a classic example of juvenile arc crust, however 1.8–2.5 Ga inherited zircon and Nd and Hf model ages have been recognized near Gunnison in central Colorado. These dAuthorsIan William Hillenbrand, Amy K. Gilmer, Michael L. Williams, Karl E. Karlstrom, Amanda (Kate) Souders, Jorge A. Vazquez, Wayne R. PremoThe importance of nodal plane orientation diversity for earthquake focal mechanism stress inversions
Inversions of earthquake focal mechanisms are among the most accessible and reliable methods for determining crustal stress. However, the use of this method varies widely, and assumptions that underpin it are often violated, potentially compromising stress estimates. We investigate the consequences of violating the little-studied assumption that the focal mechanisms have diverse orientations. OurAuthorsJens-Erik Lundstern, Eric Beauce, Orlando J. TeranGeochemical evidence for evolving Proterozoic crustal thickness and orogenic styles in southwestern Laurentia
It has long been challenging for researchers to track the crustal thickness and mode(s) of crustal modification in ancient convergent margins, limiting evaluation of the tectonic styles and processes that modify continental crust during orogenesis. We present trace element igneous geochemical crustal thickness proxies that quantitatively track the crustal thickness evolution of the long-lived ProtAuthorsIan William Hillenbrand, Karl E. Karlstrom, Michael L. Williams, Amy K. Gilmer, Wayne R. Premo, Peter B DavisFluorine-rich mafic lower crust in the southern Rocky Mountains: The role of pre-enrichment in generating fluorine-rich silicic magmas and porphyry Mo deposits
Fluorine-rich granites and rhyolites occur throughout the southern Rocky Mountains, but the origin of F-enrichment has remained unclear. We test if F-enrichment could be inherited from ancient mafic lower crust by: (1) measuring amphibole compositions, including F and Cl contents, of lower crustal mafic granulite xenoliths from northern Colorado to determine if they are unusually enriched in halogAuthorsJoshua Mark Rosera, Ryan Edward Frazer, Ryan D. Mills, Kristin Jacob, Sean P. Gaynor, Drew S. Coleman, G. Lang FarmerTriple oxygen isotope compositions of globally distributed soil carbonates record widespread evaporation of soil waters
The stable isotopic composition of pedogenic carbonates is central to many studies of past climate and topography, providing a basis for our understanding of Earth's terrestrial history. A core assumption of many applications of oxygen isotope values (δ18O) of pedogenic carbonate is that they reflect the δ18O value of precipitation (rain/snow). This assumption is violated if soil carbonates form iAuthorsJulia Kelson, Tyler E. Huth, Benjamin H. Passey, Naomi E. Levin, Sierra V. Petersen, Paolo Ballato, Emily J. Beverly, Daniel O. Breecker, Gregory D. Hoke, Adam M. Hudson, Ji Haoyuan, Alexis Licht, Jay QuadeMonazite and xenotime petrochronologic constraints on four Proterozoic tectonic episodes and ca. 1705 Ma age of the Uncompahgre Formation, southwestern Colorado, USA
The Proterozoic tectonic evolution of the south-western USA remains incompletely understood due to limited constraints on the timing and conditions of the tectono-metamorphic phases and depositional age of metasedimentary successions. We integrated multi-scale compositional mapping, petrologic modeling, and in situ geochronology to constrain pressure-temperature-time paths from samples of PaleoproAuthorsIan William Hillenbrand, Michael L. Williams, Karl E. Karlstrom, Amy K. Gilmer, Heather A. Lowers, Michael J. Jercinovic, Kaitlyn Suarez, Amanda (Kate) SoudersPaleohydrologic history of pluvial lake San Agustin, New Mexico: Tracking changing effective moisture in southwest North America through the last glacial transition
Paleoclimate records across the Intermountain West region of North America show significant regional variation in timing and magnitude of wet conditions that accompanied the last glacial-interglacial transition. To understand the climate controls on paleohydrologic change, well-dated records are needed across the region. The Plains of San Agustin (New Mexico, USA) is a closed-basin watershed of thAuthorsAdam M. Hudson, Jay Quade, Vance T. Holliday, Brendan Fenerty, Jordon Bright, Harrison J. Gray, Shannon A. MahanRevised age and regional correlations of Cenozoic strata on Bat Mountain, Death Valley region, California, USA, from zircon U-Pb geochronology of sandstones and ash-fall tuffs
Basin analysis and tectonic reconstructions of the Cenozoic history of the Death Valley region, California, USA, are hindered by a lack of volcanic (tuff) age control in many stratigraphic successions exposed in the Grapevine and Funeral Mountains of California, USA. Although maximum depositional ages (MDAs) interpreted from detrital zircon U-Pb data may be a promising alternative to volcanic agesAuthorsTheresa Maude Schwartz, Amanda (Kate) Souders, Jens-Erik Lundstern, Amy K. Gilmer, Ren A. ThompsonInsights from the Alabama Hills into Mesozoic magmatism and tectonics in eastern California
New zircon U-Pb ages for the Alabama Hills Granite in Owens Valley, eastern California, range from 103 to 102 Ma, nearly 20 Ma older than previously published zircon ages. The data preclude previously implied links between the pluton and the adjacent Late Cretaceous Mount Whitney Intrusive Suite. Geochronologic and isotopic data indicate a connection between the Alabama Hills Granite and leucogranAuthorsRyan Edward Frazer, Sean P. Gaynor, Drew S. Coleman, Jennifer M. Wenner - Web Tools
Intermountain West Seamless Geologic Map Explorer
The Intermountain West Seamless Geologic Map Explorer is an interactive mapping application that hosts surficial and bedrock geologic data layers for a transect from the Rio Grande rift to the Basin and Range.
USGS Geochron Database Explorer
This Web Application is a tool for viewing, exploring, and downloading the "USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data" Data Release.