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Adam M Hudson

I am an isotope geochemist focused on applying radiogenic and stable isotopes to understanding hydrologic and climate systems in the present and geologic past. My main research goal is to understand what affects water availability in arid regions.

My research focuses on two parallel tracks: 1) Tracing water sources in modern surface and groundwater systems and 2) reconstructing past responses of these systems to climate change through geologic mapping and isotope study of surficial deposits of lakes, rivers, soils, and desert springs and wetlands. I have done research in Tibet, the Andes, and the western United States.  My current research is focused in the US Great Basin, Alaska, and the southern Rocky Mountains of Colorado and New Mexico.

 

 

Professional Experience

  • 2020-present: Principal Investigator of Denver Radiogenic Isotope Lab, U.S. Geological Survey, Geosciences and Environmental Change Science Center, Lakewood, CO

  • 2016-present: Isotope Geochemist, U.S. Geological Survey, Geosciences and Environmental Change Science Center, Lakewood, CO

Education and Certifications

  • 2015: PhD, Geosciences/Geochemistry, University of Arizona, Tucson, AZ

  • 2011: MS, Geosciences/Geochemistry, University of Arizona, Tucson, AZ

Science and Products

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USGS

Making water tracing rock solid: national, geologic map-based visualization of USGS water strontium isotope data

Nationwide data source for USGS water strontium isotopes for hydrologic, ecologic, and forensic studies
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Community for Data Integration (CDI)
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Making water tracing rock solid: national, geologic map-based visualization of USGS water strontium isotope data

Nationwide data source for USGS water strontium isotopes for hydrologic, ecologic, and forensic studies
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Distant view of Denali

Denali National Park Geohazards Geologic Mapping

Denali National Park (DENA) is a major draw for tourism and recreation and a major economic engine for central Alaska. However, the geologic forces that created the steep landscape of DENA also make it prone to geologic hazards (geohazards) like landslides, debris flows, and earthquakes. DENA has only one major road, called the ‘Park Road’, that serves nearly all of its infrastructure. Since 2017...
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Geosciences and Environmental Change Science Center
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Denali National Park Geohazards Geologic Mapping

Denali National Park (DENA) is a major draw for tourism and recreation and a major economic engine for central Alaska. However, the geologic forces that created the steep landscape of DENA also make it prone to geologic hazards (geohazards) like landslides, debris flows, and earthquakes. DENA has only one major road, called the ‘Park Road’, that serves nearly all of its infrastructure. Since 2017...
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Mt. Ouray, Colorado with aspen colors

Geologic Framework of the Intermountain West

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...
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Geosciences and Environmental Change Science Center
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Geologic Framework of the Intermountain West

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...
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USGS science for a changing world logo

Serving the U.S. Geological Survey’s geochronological data

Geochronological data provide essential information necessary for understanding the timing of geologic processes and events, as well as quantifying rates and timescales key to geologic mapping, mineral and energy resource and hazard assessments. The USGS’s National Geochronological Database (NGDB) contains over 30,000 radiometric ages, but no formal update has occurred in over 20 years. This proj
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Community for Data Integration (CDI)
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Serving the U.S. Geological Survey’s geochronological data

Geochronological data provide essential information necessary for understanding the timing of geologic processes and events, as well as quantifying rates and timescales key to geologic mapping, mineral and energy resource and hazard assessments. The USGS’s National Geochronological Database (NGDB) contains over 30,000 radiometric ages, but no formal update has occurred in over 20 years. This proj
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Desert wetland at Point of Rocks Spring

Paleohydrology of Desert Wetlands

Springs and wetlands are among the most highly threatened ecosystems on Earth. Although geographically limited, they support more than 20% of all the threatened and endangered species in the United States. Scientists from the U.S. Geological Survey are examining the rock record to determine how springs and wetlands responded to abrupt climate change during prehistoric times and the recent geologic...
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Climate Research and Development Program, Geosciences and Environmental Change Science Center
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Paleohydrology of Desert Wetlands

Springs and wetlands are among the most highly threatened ecosystems on Earth. Although geographically limited, they support more than 20% of all the threatened and endangered species in the United States. Scientists from the U.S. Geological Survey are examining the rock record to determine how springs and wetlands responded to abrupt climate change during prehistoric times and the recent geologic...
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Isotopic, geochronologic and soil temperature data for Holocene and late Pleistocene soil carbonates of the San Luis Valley, Colorado and New Mexico, USA

This data release contains radiocarbon dates and clumped isotope ratios for soil carbonates as well as observed soil temperatures for study sites in the San Luis Valley, Colorado and New Mexico, USA. The companion publication can be found at https://doi.org/10.1029/2023GC011221.
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Geosciences and Environmental Change Science Center

Geochemical data for post-fire surface water, streambed sediment, and soils from areas affected by the 2018 Camp Fire, Butte County, California

During November 2018, the Camp Fire burned more than 150,000 acres in Butte County, California. The fire was the deadliest and most destructive in California history, destroying more than 18,000 structures and causing at least 85 fatalities. The U.S. Geological Survey sampled surface water in areas affected by the Camp Fire, plus an unburned control site, during two post-fire sampling events, Janu

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California Water Science Center, Geosciences and Environmental Change Science Center

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

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, w
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Geosciences and Environmental Change Science Center

Surficial 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 ge
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Geosciences and Environmental Change Science Center

Geochemical and isotopic data from glendonites and surrounding sediment, Carter Creek, North Slope Alaska

The dataset consists of geochemical and isotopic data from fine-grained sediments and glendonite crystals collected at Carter Creek on the North Slope of Alaska. Total Organic Carbon (TOC) values in the measured section were found to range between 0.5 and 3.5%, with a shift towards lower values in the uppermost 5 m of the section. Stable isotopes (13C) in organic matter were relatively stable thro
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Energy Resources Program, Central Energy Resources Science Center, Geology, Energy & Minerals Science Center, Geology, Geophysics, and Geochemistry Science Center, Geosciences and Environmental Change Science Center

Isotope analyses (234U/238U, 87Sr/86Sr, δ13C, and δ18O) and U-series disequilibrium ages for speleothem, water, and rock samples associated with Fitton Cave, Buffalo National River, Arkansas, USA

This data release contains tabular data (comma-separated-value files) of natural radiogenic isotopes of strontium, uranium, and thorium for samples of modern water, speleothems, associated with Fitton Cave, north central Arkansas, as well as rock that host the cave deposits. In addition, U-series ages (230Th/U dates and model 234U/238U dates) are calculated from those data for subsamples of speleo
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Geosciences and Environmental Change Science Center

Geochronologic 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.
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Geosciences and Environmental Change Science Center

Data release for the Geologic Map of the Denali Park Road Corridor, Denali National Park, Alaska

Denali National Park and Preserve (DENA), located in central Alaska, is home to iconic and dynamic landscapes surrounding the tallest mountain range in North America, the Alaska Range. DENA preserves over 6 million acres of wild land that provides opportunities for recreation, subsistence hunting and gathering, preservation of cultural resources, and scientific research. Despite its size and popul
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Geosciences and Environmental Change Science Center

USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data (ver. 2.0, September 2023)

USGS Geochron is a database of geochronological and thermochronological dates and data. The data set contains published ages, dates, analytical information, sample metadata including location, and source citations. The following analytical techniques are represented in the data set: 40Ar/39Ar, K-Ar, U-Th-Pb, Sm-Nd, Rb-Sr, Lu-Hf, fission track, and luminescence. This data set incorporates data prev
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Community for Data Integration (CDI), Geosciences and Environmental Change Science Center

Data Release for Reconstructing paleohydrology in the northwest Great Basin since the last deglaciation using Paisley Caves fish remains (Oregon, U.S.A.)

This dataset includes tables of stratigraphic age-depth information for Paisley Caves 2 and 5, in Oregon U.S.A., along with tables of fish bone abundance and stable and strontium isotopic data for fish remains and geological samples from the study area surrounding the Paisley Caves.
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National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center

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

This dataset includes tables of 3He-isotopic data used to calculate surface exposure ages for samples of basalt, and U- and Th-isotopic data used to calculate uranium-series age estimates (230Th/U method) and initial 234U/238U activity ratios for samples of pedogenic carbonate formed in soils on alluvial fans in the San Luis Valley, Colorado, USA. These data are included in the publication: Rule
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National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center

Data Rease for "Isotopic constraints on middle Pleistocene cave evolution, paleohydrologic flow, and environmental conditions from Fitton Cave speleothems, Buffalo National River, Arkansas"

Data release for "Isotopic constraints on middle Pleistocene cave evolution, paleohydrologic flow, and environmental conditions from Fitton Cave speleothems, Buffalo National River, Arkansas". Extended abstract for the 2017 Karst Interest Group meeting. Includes sample information, U-Th isotope compositions, calculated U-series (230Th/U) ages and initial 234U/238U activity ratios, Sr isotopic co
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National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center
Filter Total Items: 16

Clumped isotopes record a glacial-interglacial shift in seasonality of soil carbonate accumulation in the San Luis Valley, southern Rocky Mountains, USA

Clumped isotope paleothermometry using pedogenic carbonates is a powerful tool for investigating past climate changes. However, location-specific seasonal patterns of precipitation and soil moisture cause systematic biases in the temperatures they record, hampering comparison of data across large areas or differing climate states. To account for biases, more systematic studies of carbonate forming
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Adam M. Hudson, Julia R. Kelson, James B. Paces, Chester A. Ruleman, Katharine W. Huntington, Andrew J. Schauer
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Geosciences and Environmental Change Science Center

Insights into glendonite formation from the upper Oligocene Sagavanirktok Formation, North Slope, Alaska

The type locality for the upper Oligocene Nuwok Member of the Sagavanirktok Formation (Carter Creek, North Slope, Alaska, USA) contains abundant occurrence of glendonite, a pseudomorph after the calcium carbonate mineral ikaite, which typically forms in the shallow subsurface of cold marine sediments. The region during the time of Nuwok Member deposition was located at a high latitude, similar to
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John W. Counts, Madeleine Vickers, Martha (Rebecca) Stokes, Whittney Spivey, Kristina Frank Gardner, Jean Self-Trail, Jared T. Gooley, Ryan J. McAleer, Aaron M. Jubb, David W. Houseknecht, Richard O. Lease, Neil Patrick Griffis, Martin S. Vickers, Kasia Śliwińska, Hannah Gail Dooley Tompkins, Adam M. Hudson
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Ecosystems Mission Area, Energy Resources Program, Geology, Geophysics, and Geochemistry Science Center, Alaska Science Center, Florence Bascom Geoscience Center, Geology, Energy & Minerals Science Center, Geosciences and Environmental Change Science Center

Triple 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 i
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Julia 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 Quade
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Geosciences and Environmental Change Science Center

Paleohydrologic 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 th
Authors
Adam M. Hudson, Jay Quade, Vance T. Holliday, Brendan Fenerty, Jordon Bright, Harrison J. Gray, Shannon A. Mahan
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Geosciences and Environmental Change Science Center

The Seamless Integrated Geologic Mapping (SIGMa) extension to the Geologic Map Schema (GeMS)

Geologic maps are the fundamental building blocks of surface and subsurface three-dimensional geologic framework models of the Earth’s crust. However, as the production and availability of geologic map databases continues to increase, inconsistent data models and the lack of synthesized, national geologic map data at scales appropriate for informed decision making negatively affect the functional
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Kenzie J. Turner, Jeremiah B. Workman, Joseph Colgan, Amy K. Gilmer, Margaret E. Berry, Samuel Johnstone, Kathleen F. Warrell, Marieke Dechesne, D. Paco VanSistine, Ren A. Thompson, Adam M. Hudson, Kristine L. Zellman, Donald S. Sweetkind, Chester A. Ruleman
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Geosciences and Environmental Change Science Center

Central Andean (28–34°S) flood record 0–25 ka from Salinas del Bebedero, Argentina

The Salinas del Bebedero occupies an isolated basin in the foreland of central Argentina at 33°S and was flooded repeatedly over past 25 ka. Isotopic evidence demonstrates that this flooding was due to overflow of the nearby Río Desaguadero with waters derived from the distant (≥300 km) central Andes between 28–34°S. Stratigraphic and shoreline evidence shows that floods occurred most frequently b
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Jay Quade, Elad Dente, Allison Cartwright, Adam M. Hudson, Sebastian Jimenez, David McGee
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National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center

Evidence for humans in North America during the Last Glacial Maximum

Archaeologists and researchers in allied fields have long sought to understand human colonization of North America. When, how, and from where did people migrate, and what were the consequences of their arrival for the established fauna and landscape are enduring questions. Here, we present evidence from excavated surfaces of in situ human footprints from White Sands National Park (New Mexico, USA)
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Matthew R. Bennett, David Bustos, Jeffrey S. Pigati, Kathleen B. Springer, Thomas. M. Urban, Vance T. Holliday, Sally C. Reynolds, Marcin Budka, Jeffrey S. Honke, Adam M. Hudson, Brendan Fenerty, Clare Connelly, Patrick J. Martinez, Vincent L. Santucci, Daniel Odess
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Climate Research and Development Program, National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center

Reconstructing paleohydrology in the northwest Great Basin since the last deglaciation using Paisley Caves fish remains (Oregon, U.S.A.)

The arid northwest Great Basin underwent substantial hydroclimate changes in the past 15,000 years, greatly affecting its desert ecosystems and prehistoric people. There are conflicting interpretations of the timing of hydrologic changes in this region, requiring more records to resolve the dominant climatic drivers. The Paisley Caves archaeological site, located near former pluvial Lake Chewaucan
Authors
Adam M. Hudson, Meaghan M Emery-Wetherell, Patrick M Lubinski, Virginia L. Butler, Deanna N Grimstead, Dennis L Jenkins
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National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center

Assessing geohazards to the Denali National Park road with geologic mapping

Denali National Park (DENA) is home to iconic and breathtaking landscapes surrounding the tallest mountain range in North America, the Alaska Range. The park, which covers 6 million acres, is a major draw for tourism and recreation, making it an important economic engine for central Alaska. However, the geologic forces that created the beautiful, steep landscape of DENA also make it prone to geolo
Authors
Adam M. Hudson, Chester A. Ruleman, Denny M Capps
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Geosciences and Environmental Change Science Center

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

The Rio Grande is the fourth longest river in North America extending over 3,000 km from the Rocky Mountains to the Gulf of Mexico. The Pleistocene evolution of this river from individual subbasins into a coalesced fluvial system has been long debated. Herein, we constrain the middle Pleistocene evolution of the northernmost and largest Rio Grande basin, the San Luis basin, and the timing of incis
Authors
Chester A. Ruleman, Adam M. Hudson, Ren A. Thompson, Daniel P. Miggins, James B. Paces, Brent M. Goehring
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National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center

North-south dipole in winter hydroclimate in the western United States during the last deglaciation

During the termination of the last glacial period the western U.S. experienced exceptionally wet conditions, driven by changes in location and strength of the mid-latitude winter storm track. The distribution of modern winter precipitation is frequently characterized by a north-south wet/dry dipole pattern, controlled by interaction of the storm track with ocean-atmosphere conditions over the Paci
Authors
Adam M. Hudson, Benjamin J. Hatchett, Jay Quade, Douglas P. Boyle, Scott D. Bassett, Guleed Ali, Marie G. De los Santos
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Climate Research and Development Program, National Cooperative Geologic Mapping Program, Geosciences and Environmental Change Science Center

Establishing chronologies for alluvial-fan sequences with analysis of high-resolution topographic data: San Luis Valley, Colorado, USA

On active alluvial fans, debris-flow deposits and frequent avulsions produce a rough topographic surface. As is the case in many initially rough landforms produced by catastrophic processes, the topography of alluvial fans is progressively smoothed, producing textural differences useful in establishing relative age criteria for fans. Here, we outline an approach for defining a quantitative, numeri
Authors
Samuel Johnstone, Adam M. Hudson, Sylvia Nicovich, Chester A. Ruleman, Robert M. Sare, Ren A. Thompson
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National Cooperative Geologic Mapping Program, Geology, Geophysics, and Geochemistry Science Center, Geosciences and Environmental Change Science Center

Non-USGS Publications**

Licht, A., Quade, J., Kowler, A., de Los Santos, M., Hudson, A., Schauer, A., Huntington, K., Copeland, P., Lawton, T., 2017. Impact of the North American monsoon on isotope paleoaltimeters: implications for the paleoaltimetry of the American Southwest. American Journal of Science 317, 1-33.
Conroy, J.L, Hudson, A.M., Overpeck, J.T., Liu K.-B., Wang L., 2017. The primacy of multidecadal to centennial variability of late-Holocene forced change of the Asian Monsoon on the southern Tibetan Plateau. Earth and Planetary Science Letters 458, 337-348.
Hudson, A.M., Olsen, J.W., Quade, J., Lei G., Huth, T.E., Zhang H., 2016. A regional record of expanded Holocene wetlands and prehistoric human occupation from paleowetland deposits of the western Yarlung Tsangpo valley, Tibetan Plateau. Quaternary Research 86, 13-33.
Perreault, C., Boulanger, M.T., Hudson, A.M., Rhode, D., Madsen, D.B., Olsen, J.W., Steffen, M.L., Quade, J., Glascock, M.D., Brantingham, P.J., 2016. Characterization of obsidian from the Tibetan Plateau by XRF and NAA. Journal of Archaeological Science: Reports 5, 392-399.
Phillips, F.M., Kelly, M.A., Hudson, A.M., Stone, J.O.H., Schaefer, J., Marrero, S., Fifield, K., Finkel, R., Lowell, T.V., 2016, CRONUS-Earth calibrations samples from the Huancané moraines, Quelccaya Ice Cap, Peru. Quaternary Geochronology, 31, 220-236.
Phillips, F.M., Argento, D.C., Balco, G., Caffee, M.W., Clem, J., Dunai, T.J., Finkel, R., Goehring, B., Gosse, J.C., Hudson, A.M., Jull, A.J.T., Kelly, M.A., Kurz, M., Lal, D., Lifton, N., Marrero, S.M., Nishiizumi, K., Reedy, R.C., Schaefer, J., Stone, J.O.H., Swanson, T., Zreda, M.G., 2016, The CRONUS-Earth project: a synthesis. Quaternary Geochronology 31, 119-154.
Phillips, F.M., Argento, D.C., Bourles, D.L., Caffee, M.W., Dunai, T.J., Goehring, B., Gosse, J.C., Hudson, A.M., Jull, A.J.T., Kelly, M., Lifton, N., Marrero, S.M., Nishiizumi, K., Reedy, R.C., Stone, J.O.H., 2016, Where now? Reflections on future directions for cosmogenic nuclide research from the CRONUS Projects. Quaternary Geochronology 31, 155-159.
Hudson, A.M., Quade, J., Huth, T.E., Lei G., Cheng H., Edwards, R.L., Olsen, J.W., and Zhang H., 2015, Lake level reconstruction for 12.8-2.3 ka for the Ngangla Ring Tso closed-basin lake system, southwest Tibetan Plateau. Quaternary Research 83, 66-79.
Huth, T.E., Hudson, A.M., Quade J., Lei G., and Zhang H., 2015, Paleohydrologic reconstruction of Holocene climate 11.5-5.0 ka based on shoreline dating and hydrologic budget modeling of Baqan Tso, southwestern Tibetan Plateau. Quaternary Research 83, 80-93.
Grimstead, D.N., Reynolds, A.C., Hudson, A.M., Akins, N.J., Betancourt, J.L., 2015, Low 87Sr/86Sr variance in turkey remains reveal domestication at Chaco Canyon. Journal of Archaeological Methods and Theory 23, 127-149
Hudson, A.M., Olsen, J.W., and Quade, J., 2014, Radiocarbon dating of interdune paleowetland deposits to constrain the age of mid- to Late Holocene microlithic artifacts from the Zhongba site, southwestern Qinghai-Tibet Plateau. Geoarchaeology 29, 33-46.
Huntington, K.W., Saylor, J., Quade, J., and Hudson, A.M., 2015, New constraints on Tibetan Plateau uplift from carbonate clumped isotope thermometry. Geological Society of America Bulletin 127, 181-199.
Kelly, M.A., Lowell, T.V., Applegate, P.J., Phillips, F.M., Schaefer, J.M., Smith, C.A., Kim, H., Leonard, K., and Hudson, A.M., 2015, A locally calibrated late glacial 10Be production rate from a low-latitude, high-altitude site in the Peruvian Andes: Quaternary Geochronology 26, 70-85
Hudson, A.M., and Quade, J., 2013, Long-term asymmetry in monsoon climate on the Tibetan Plateau: Geology 41, 351-354.
Kelly, M.A., Lowell, T.V., Applegate, P.J., Smith, C.A., Phillips, F.M., and Hudson, A.M., 2012, Late glacial fluctuations of Quelccaya Ice Cap, southeastern Peru: Geology 40, 991-994.
Pelletier, J.D., Engelder, T.M., Comeau, D., Hudson, A., Leclerc, M., Youberg, A., and Diniega, S., 2009. Tectonic and structural control of fluvial channel morphology in metamorphic core complexes: The example of the Catalina-Rincon core complex, Arizona, Geosphere, 5, 363-384.

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

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