Shannon Mahan
My work focuses on the geochronology and associated dosimetry of luminescence dating, with the goal of understanding when, how, and the rates at which mineral grains acquire (and lose!) their luminescence signal.
I graduated from Adams State University (Colorado) with a B.S. in Geology in 1987 and was immediately hired into the USGS in April 1987. For those of you that are counting, this makes me the end of the “baby boomers” and working well into my third decade with the USGS. My career has been as varied as my interests, as I have worked in radiogenic isotopes, hydrology, stable isotopes, gamma spectrometry, and luminescence. I have been the USGS Luminescence Geochronology Lab Director since 1997 and routinely work on 20 to 30 projects during a year throughout the USGS mission areas.
Over the past 40 years, luminescence dating has become a key tool for dating sediments of interest in geologic, paleontologic, and archeologic research and this is my obvious scientific interest. Luminescence is also used to date paleoseismology sites, fluvial terraces (including paleoflood deposits), eolian deposits, and is increasingly used to calibrate wildfire temperatures, sediment transport processes, and thermochronology. The flexibility of luminescence is a key complement to other chronometers such as radiocarbon or cosmogenic nuclides. Like all geochronologic techniques, context is necessary for interpreting and calculating luminescence results and this can be achieved by supplying our lab with associated trench logs, photos, and stratigraphic locations of sample sites if you choose to work with us (Taken from Gray et al, 2015 paper Guide to Luminescence Dating Techniques and their Application for Paleoseismic Research; Mahan and DeWitt, 2019, Principles and history of Luminescence Dating Chapter 1 in Handbook of Luminescence Dating AND Mahan et al, 2022 guide for interpretating and reporting luminescence dating results).
The USGS Luminescence Geochronology Lab is composed of myself, Harrison Gray, and Emma Krolczyk. We are an integral part of multi-disciplinary, multi-agency, and multi-institutional projects that provide chronologic control for Quaternary field studies in the continental United States. The growth of the laboratory is due to the science that our partnership can generate with many other science agencies, both Federal, state, and academic. Additional publications and projects can be viewed from USGS Luminescence Dating Laboratory and on Research Gate.
Professional Experience
2023 - present: Acting Deputy Center Director
2021 - present: TRIGA Reactor System Administrator and Science Advisor
2008 - present: Research Geologist
1987 - 2008: Geologist
Education and Certifications
1986: B.S., Geology, Adams State College
Affiliations and Memberships*
Geological Society of America
Friends of the Pleistocene
INQUA
Science and Products
Filter Total Items: 139
How similar was the 1983 Mw 6.9 Borah Peak earthquake rupture to its surface-faulting predecessors along the northern Lost River fault zone (Idaho, USA)?
We excavated trenches at two paleoseismic sites bounding a trans-basin bedrock ridge (the Willow Creek Hills) along the northern Lost River fault zone to explore the uniqueness of the 1983 Mw 6.9 Borah Peak earthquake compared to its prehistoric predecessors. At the Sheep Creek site on the southernmost Warm Springs section, two earthquakes occurred at 9.8−14.0 ka (95% confidence) and 6.5...
Authors
Christopher DuRoss, Richard W. Briggs, Ryan D. Gold, Alexandra Elise Hatem, Austin John Elliott, Jaime E. Delano, Ivan Medina-Cascales, Harrison J. Gray, Shannon A. Mahan, Sylvia R. Nicovich, Zachery Lifton, Emily J. Kleber, Greg N. McDonald, Adam I. Hiscock, Michael P. Bunds, Nadine G. Reitman
Photomosaics and logs associated with study of West Napa Fault at Ehlers Lane, north of Saint Helena, California
The West Napa Fault has previously been mapped as extending ~45 kilometers (km) from northern Vallejo to southern Saint Helena, California, dominantly running along the western edge of Napa Valley. A zone of fault strands (some previously unmapped) along a ~15-km section of the fault ruptured during the 2014 magnitude 6.0 South Napa earthquake, illustrating the need for further...
Authors
Belle E. Philibosian, Robert R. Sickler, Carol S. Prentice, Alexandra J. Pickering, Patrick Gannon, Kiara N. Broudy, Shannon A. Mahan, Jazmine N. Titular, Eli A. Turner, Cameron Folmar, Sierra F. Patterson, Emilie E. Bowman
A maximum rupture model for the central and southern Cascadia subduction zone—reassessing ages for coastal evidence of megathrust earthquakes and tsunamis
A new history of great earthquakes (and their tsunamis) for the central and southern Cascadia subduction zone shows more frequent (17 in the past 6700 yr) megathrust ruptures than previous coastal chronologies. The history is based on along-strike correlations of Bayesian age models derived from evaluation of 554 radiocarbon ages that date earthquake evidence at 14 coastal sites. We...
Authors
Alan R. Nelson, Christopher DuRoss, Robert Witter, Harvey M. Kelsey, Simon E. Engelhart, Shannon A. Mahan, Harrison J. Gray, Andrea D. Hawkes, Benjamin P. Horton, Jason Scott Padgett
Synthesis of geochronologic research on Late Pliocene to Holocene emergent shorelines in the lower Savannah River area of southeastern Georgia, USA
Emergent late Pliocene and Pleistocene shoreline deposits, morphologically identifiable Pleistocene shoreline units, and seaward-facing scarps characterize the easternmost Atlantic Coastal Plain (ACP) of the United States of America. In some areas of the ACP, these deposits, units, and scarps have been studied in detail. Within these areas, temporal and spatial data are sufficient for...
Authors
Helaine W. Markewich, Milan J. Pavich, Shannon A. Mahan, Paul R. Bierman, Wilma B. Alemán‑González, Arthur P. Schultz
River terrace evidence of tectonic processes in the eastern North American plate interior, South Anna River, Virginia
We show that long-recognized seismicity in the central Virginia seismic zone of the eastern North American intraplate setting arises primarily from tectonic processes predicted by new, fully coupled plate tectonic geodynamic models. The study leverages much new geophysical and geologic data following the 2011 Mineral, Virginia, earthquake that ruptured a steeply dipping, northwest...
Authors
Frank J. Pazzaglia, Helen F. Malenda, Matthew L. McGavick, Cody Raup, Mark W. Carter, Claudio Berti, Shannon A. Mahan, Michelle Summa Nelson, Tammy M. Rittenour, Ronald C. Counts, Jane K Willenbring, Dru Germanoski, Stephen Peters, William D. Holt
Holocene paleoseismology of the Steamboat Mountain Site: Evidence for full‐Llngth rupture of the Teton Fault, Wyoming
The 72‐km‐long Teton fault in northwestern Wyoming is an ideal candidate for reconstructing the lateral extent of surface‐rupturing earthquakes and testing models of normal‐fault segmentation. To explore the history of earthquakes on the northern Teton fault, we hand‐excavated two trenches at the Steamboat Mountain site, where the east‐dipping Teton fault has vertically displaced west...
Authors
Christopher DuRoss, Mark S. Zellman, Glenn R. Thackray, Richard W. Briggs, Ryan D. Gold, Shannon A. Mahan
Depth-dependent soil mixing persists across climate zones
Soil mixing over long (>102 y) timescales enhances nutrient fluxes that support soil ecology, contributes to dispersion of sediment and contaminated material, and modulates fluxes of carbon through Earth’s largest terrestrial carbon reservoir. Despite its foundational importance, we lack robust understanding of the rates and patterns of soil mixing, largely due to a lack of long...
Authors
Harrison J. Gray, Amanda Keen-Zebert, David J. Furbish, Gregory E. Tucker, Shannon A. Mahan
Neotectonic and paleoseismic analysis of the northwest extent of Holocene surface deformation along the Meers Fault, Oklahoma
TheMeers fault (Oklahoma) is one of fewseismogenic structures with evidence for Holocene surface rupture in the stable continental region of North America. The 37-kilometer-long southeast section of the full 54-kilometer-long Meers fault is interpreted to be Holocene active. The 17-kilometer-long northwest section is considered Quaternary active, but not Holocene active.We reevaluate...
Authors
Kristofer T. Hornsby, Ashley R. Streig, Scott E.K. Bennett, Jefferson Chang, Shannon A. Mahan
Holocene earthquake history and slip rate of the southern Teton fault, Wyoming, USA
The 72-km-long Teton normal fault bounds the eastern base of the Teton Range in northwestern Wyoming, USA. Although geomorphic surfaces along the fault record latest Pleistocene to Holocene fault movement, the postglacial earthquake history of the fault has remained enigmatic. We excavated a paleoseismic trench at the Buffalo Bowl site along the southernmost part of the fault to...
Authors
Christopher DuRoss, Ryan D. Gold, Richard W. Briggs, Jaime E. Delano, Dean A. Ostenaa, Mark S. Zellman, Nicole Cholewinski, Seth Wittke, Shannon A. Mahan
Pleistocene lakes and paleohydrologic environments of the Tecopa basin, California: Constraints on the drainage integration of the Amargosa River
The Tecopa basin in eastern California was a terminal basin that episodically held lakes during most of the Quaternary until the basin and its modern stream, the Amargosa River, became tributary to Death Valley. Although long studied for its sedimentology, diagenesis, and paleomagnetism, the basin’s lacustrine and paleoclimate history has not been well understood, and conflicting...
Authors
Marith C. Reheis, John Caskey, Jordon E. Bright, James B. Paces, Shannon A. Mahan, Elmira Wan
Holocene rupture history of the central Teton fault at Leigh Lake; Grand Teton National Park, Wyoming
Prominent scarps on Pinedale glacial surfaces along the eastern base of the Teton Range confirm latest Pleistocene to Holocene surface‐faulting earthquakes on the Teton fault, but the timing of these events is only broadly constrained by a single previous paleoseismic study. We excavated two trenches at the Leigh Lake site near the center of the Teton fault to address open questions...
Authors
Mark S. Zellman, Christopher DuRoss, Glenn R. Thackray, Stephen Personius, Nadine G. Reitman, Shannon A. Mahan, Cooper C. Brossy
Quaternary displacement on the Joiner Ridge Fault, eastern Arkansas
The New Madrid seismic zone of the central United States is an intraplate seismic zone with blind structures that are not seismically active but may pose seismic hazards. The Joiner Ridge fault is the 35 km long east-bounding fault of the Joiner Ridge blind horst located in eastern Arkansas approximately 50 km northwest of Memphis, Tennessee. Shallow S-wave (SH-mode) seismic reflection...
Authors
Audrey C. Price, Edward W Woolery, Ronald C. Counts, Roy Van Arsdale, Daniel Larsen, Shannon A. Mahan, Glynn Beck
Filter Total Items: 25
Data Release for Luminescence: Late Holocene rupture history of the Ash Hill Fault, Eastern California Shear Zone, and the potential for seismogenic strain transfer between nearby faults
The following report summarizes the dating results from sedimentary deposits exposed by soil pits in Panamint Valley, CA. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating-related calculations.
Data Release for Luminescence: Paleoseismic liquefaction associated with Holocene earthquakes on the Wallula Fault zone, Southeast Washington, USA
Observations of widespread liquefaction and stratigraphic and structural relationships in a trench across an ambiguous scarp are used to constrain the timing of Holocene earthquakes on the northwest-striking Wallula fault zone in southeast Washington and Oregon. Additional observations and age constraints from OSL analysis of samples collected from large-scale liquefaction features that...
Data Release for Luminescence: Mid to Late Quaternary Geomorphic and Paleoseismic Event History, Cheraw Fault, Colorado
Despite its subdued expression and isolated location within the Great Plains of southeastern Colorado, the 80-km-long Cheraw fault may be one of the most active faults in North America east of the Southern Rocky Mountains. We present geomorphic analyses, geochronology, and paleoseismic trenching data to 1) document the rupture history of the ~45-km-long southwestern section of the Cheraw...
Data Release for Luminescence: Luminescence data for Natural Trap Cave, Wyoming
The following report summarizes the dating results from the Natural Trap Cave 2018-2019 dating project. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating-related calculations. We recommend that this report be included...
Data Release for Luminescence: Floodplain Sediment Storage Timescales of the Laterally Confined Meandering Powder River, U.S.A
The following report summarizes the dating results from the. Within this report, we detail the methodology used to determine the storage time distribution for a 17 km length of Powder River in Montana, U.S.A. by the age distribution of eroded sediment. This data is used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence...
Data release for luminescence: Edwards Air Force Base (CA) and CA Water Science Center report including luminescence data and ages
The following report summarizes the dating results from Aeolian deposits within and around Edwards Air Force Base in California. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating related calculations. We recommend that...
Bringing the South Dakota southern Black Hills Mammoth Site formation and fossil discovery to light: a chronological reassignment using Luminescence Dating
The Mammoth Springs (MS) fossil site at Hot Springs, South Dakota, provides a unique opportunity to reconstruct paleoenvironmental conditions. We used luminescence dating on fine sand sized potassium feldspars to establish a chronological framework for the site. In addition, we dated a late Pleistocene paludal proxy site using luminescence and incorporated those results with previous...
Geologic setting and geomorphic history of the La Botica area, south-central Colorado
La Botica is positioned on a topographic bench sharply inset into the gentle eastern slope of the high San Juan Mountains and perched ~70-80 meters above La Jara Creek (fig. 1), a tributary to the Rio Grande. Quaternary surface processes have modified the Tertiary bedrock deposits that underlie La Botica to shape the physical environment. Bedrock deposits consist of Oligocene to Pliocene...
Optically Stimulated Luminescence (OSL) data and ages for selected Native American Sacred Ceremonial Stone Landscape features--Final Project Report Submitted to the Narragansett Tribal Historic Preservation Trust
Stone rows, enclosures, structures and chambers can be found in the landscapes of Massachusetts and Rhode Island. Structures similar to those shown in the cover photo are documented elsewhere. The age, cultural affiliation, and purpose of these stone structures--which are found in a variety of forms, such as piles arranged in spatial configurations across landscapes, shapes suggesting...
DATA RELEASE Part 2: Optical luminescence dating of Bradley Lake, Oregon, tsunami deposits, analytical data for: A maximum rupture model for the central and southern Cascadia subduction zone-reassessing ages for coastal evidence of megathrust earthquakes
The following report summarizes the dating results from Bradley Lake, Oregon. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and datingrelated calculations. We recommend that this report be included as the supplementary...
Data release for application of a luminescence-based sediment transport model
This data release contains luminescence data from the manuscript "Application of a luminescence-based sediment transport model" by Gray et al. It contains data from the luminescence measurements and experiments in the paper.
OSL methods and field and laboratory data for Mesa Verde soils to support journal article
Thin loess deposits on the uplands of the southeastern Colorado Plateau have previously not been well studied. We sampled deposits and soils from trenches on Hatch Point mesa near Canyonlands National Park, Utah, and from two outcrops in Mesa Verde National Park, Colorado. At Hatch Point, the oldest buried unit yielded two OSL ages of 10,370 and 7,555 yr; the middle unit yielded 10 OSL...
Filter Total Items: 15
Science and Products
Filter Total Items: 139
How similar was the 1983 Mw 6.9 Borah Peak earthquake rupture to its surface-faulting predecessors along the northern Lost River fault zone (Idaho, USA)?
We excavated trenches at two paleoseismic sites bounding a trans-basin bedrock ridge (the Willow Creek Hills) along the northern Lost River fault zone to explore the uniqueness of the 1983 Mw 6.9 Borah Peak earthquake compared to its prehistoric predecessors. At the Sheep Creek site on the southernmost Warm Springs section, two earthquakes occurred at 9.8−14.0 ka (95% confidence) and 6.5...
Authors
Christopher DuRoss, Richard W. Briggs, Ryan D. Gold, Alexandra Elise Hatem, Austin John Elliott, Jaime E. Delano, Ivan Medina-Cascales, Harrison J. Gray, Shannon A. Mahan, Sylvia R. Nicovich, Zachery Lifton, Emily J. Kleber, Greg N. McDonald, Adam I. Hiscock, Michael P. Bunds, Nadine G. Reitman
Photomosaics and logs associated with study of West Napa Fault at Ehlers Lane, north of Saint Helena, California
The West Napa Fault has previously been mapped as extending ~45 kilometers (km) from northern Vallejo to southern Saint Helena, California, dominantly running along the western edge of Napa Valley. A zone of fault strands (some previously unmapped) along a ~15-km section of the fault ruptured during the 2014 magnitude 6.0 South Napa earthquake, illustrating the need for further...
Authors
Belle E. Philibosian, Robert R. Sickler, Carol S. Prentice, Alexandra J. Pickering, Patrick Gannon, Kiara N. Broudy, Shannon A. Mahan, Jazmine N. Titular, Eli A. Turner, Cameron Folmar, Sierra F. Patterson, Emilie E. Bowman
A maximum rupture model for the central and southern Cascadia subduction zone—reassessing ages for coastal evidence of megathrust earthquakes and tsunamis
A new history of great earthquakes (and their tsunamis) for the central and southern Cascadia subduction zone shows more frequent (17 in the past 6700 yr) megathrust ruptures than previous coastal chronologies. The history is based on along-strike correlations of Bayesian age models derived from evaluation of 554 radiocarbon ages that date earthquake evidence at 14 coastal sites. We...
Authors
Alan R. Nelson, Christopher DuRoss, Robert Witter, Harvey M. Kelsey, Simon E. Engelhart, Shannon A. Mahan, Harrison J. Gray, Andrea D. Hawkes, Benjamin P. Horton, Jason Scott Padgett
Synthesis of geochronologic research on Late Pliocene to Holocene emergent shorelines in the lower Savannah River area of southeastern Georgia, USA
Emergent late Pliocene and Pleistocene shoreline deposits, morphologically identifiable Pleistocene shoreline units, and seaward-facing scarps characterize the easternmost Atlantic Coastal Plain (ACP) of the United States of America. In some areas of the ACP, these deposits, units, and scarps have been studied in detail. Within these areas, temporal and spatial data are sufficient for...
Authors
Helaine W. Markewich, Milan J. Pavich, Shannon A. Mahan, Paul R. Bierman, Wilma B. Alemán‑González, Arthur P. Schultz
River terrace evidence of tectonic processes in the eastern North American plate interior, South Anna River, Virginia
We show that long-recognized seismicity in the central Virginia seismic zone of the eastern North American intraplate setting arises primarily from tectonic processes predicted by new, fully coupled plate tectonic geodynamic models. The study leverages much new geophysical and geologic data following the 2011 Mineral, Virginia, earthquake that ruptured a steeply dipping, northwest...
Authors
Frank J. Pazzaglia, Helen F. Malenda, Matthew L. McGavick, Cody Raup, Mark W. Carter, Claudio Berti, Shannon A. Mahan, Michelle Summa Nelson, Tammy M. Rittenour, Ronald C. Counts, Jane K Willenbring, Dru Germanoski, Stephen Peters, William D. Holt
Holocene paleoseismology of the Steamboat Mountain Site: Evidence for full‐Llngth rupture of the Teton Fault, Wyoming
The 72‐km‐long Teton fault in northwestern Wyoming is an ideal candidate for reconstructing the lateral extent of surface‐rupturing earthquakes and testing models of normal‐fault segmentation. To explore the history of earthquakes on the northern Teton fault, we hand‐excavated two trenches at the Steamboat Mountain site, where the east‐dipping Teton fault has vertically displaced west...
Authors
Christopher DuRoss, Mark S. Zellman, Glenn R. Thackray, Richard W. Briggs, Ryan D. Gold, Shannon A. Mahan
Depth-dependent soil mixing persists across climate zones
Soil mixing over long (>102 y) timescales enhances nutrient fluxes that support soil ecology, contributes to dispersion of sediment and contaminated material, and modulates fluxes of carbon through Earth’s largest terrestrial carbon reservoir. Despite its foundational importance, we lack robust understanding of the rates and patterns of soil mixing, largely due to a lack of long...
Authors
Harrison J. Gray, Amanda Keen-Zebert, David J. Furbish, Gregory E. Tucker, Shannon A. Mahan
Neotectonic and paleoseismic analysis of the northwest extent of Holocene surface deformation along the Meers Fault, Oklahoma
TheMeers fault (Oklahoma) is one of fewseismogenic structures with evidence for Holocene surface rupture in the stable continental region of North America. The 37-kilometer-long southeast section of the full 54-kilometer-long Meers fault is interpreted to be Holocene active. The 17-kilometer-long northwest section is considered Quaternary active, but not Holocene active.We reevaluate...
Authors
Kristofer T. Hornsby, Ashley R. Streig, Scott E.K. Bennett, Jefferson Chang, Shannon A. Mahan
Holocene earthquake history and slip rate of the southern Teton fault, Wyoming, USA
The 72-km-long Teton normal fault bounds the eastern base of the Teton Range in northwestern Wyoming, USA. Although geomorphic surfaces along the fault record latest Pleistocene to Holocene fault movement, the postglacial earthquake history of the fault has remained enigmatic. We excavated a paleoseismic trench at the Buffalo Bowl site along the southernmost part of the fault to...
Authors
Christopher DuRoss, Ryan D. Gold, Richard W. Briggs, Jaime E. Delano, Dean A. Ostenaa, Mark S. Zellman, Nicole Cholewinski, Seth Wittke, Shannon A. Mahan
Pleistocene lakes and paleohydrologic environments of the Tecopa basin, California: Constraints on the drainage integration of the Amargosa River
The Tecopa basin in eastern California was a terminal basin that episodically held lakes during most of the Quaternary until the basin and its modern stream, the Amargosa River, became tributary to Death Valley. Although long studied for its sedimentology, diagenesis, and paleomagnetism, the basin’s lacustrine and paleoclimate history has not been well understood, and conflicting...
Authors
Marith C. Reheis, John Caskey, Jordon E. Bright, James B. Paces, Shannon A. Mahan, Elmira Wan
Holocene rupture history of the central Teton fault at Leigh Lake; Grand Teton National Park, Wyoming
Prominent scarps on Pinedale glacial surfaces along the eastern base of the Teton Range confirm latest Pleistocene to Holocene surface‐faulting earthquakes on the Teton fault, but the timing of these events is only broadly constrained by a single previous paleoseismic study. We excavated two trenches at the Leigh Lake site near the center of the Teton fault to address open questions...
Authors
Mark S. Zellman, Christopher DuRoss, Glenn R. Thackray, Stephen Personius, Nadine G. Reitman, Shannon A. Mahan, Cooper C. Brossy
Quaternary displacement on the Joiner Ridge Fault, eastern Arkansas
The New Madrid seismic zone of the central United States is an intraplate seismic zone with blind structures that are not seismically active but may pose seismic hazards. The Joiner Ridge fault is the 35 km long east-bounding fault of the Joiner Ridge blind horst located in eastern Arkansas approximately 50 km northwest of Memphis, Tennessee. Shallow S-wave (SH-mode) seismic reflection...
Authors
Audrey C. Price, Edward W Woolery, Ronald C. Counts, Roy Van Arsdale, Daniel Larsen, Shannon A. Mahan, Glynn Beck
Filter Total Items: 25
Data Release for Luminescence: Late Holocene rupture history of the Ash Hill Fault, Eastern California Shear Zone, and the potential for seismogenic strain transfer between nearby faults
The following report summarizes the dating results from sedimentary deposits exposed by soil pits in Panamint Valley, CA. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating-related calculations.
Data Release for Luminescence: Paleoseismic liquefaction associated with Holocene earthquakes on the Wallula Fault zone, Southeast Washington, USA
Observations of widespread liquefaction and stratigraphic and structural relationships in a trench across an ambiguous scarp are used to constrain the timing of Holocene earthquakes on the northwest-striking Wallula fault zone in southeast Washington and Oregon. Additional observations and age constraints from OSL analysis of samples collected from large-scale liquefaction features that...
Data Release for Luminescence: Mid to Late Quaternary Geomorphic and Paleoseismic Event History, Cheraw Fault, Colorado
Despite its subdued expression and isolated location within the Great Plains of southeastern Colorado, the 80-km-long Cheraw fault may be one of the most active faults in North America east of the Southern Rocky Mountains. We present geomorphic analyses, geochronology, and paleoseismic trenching data to 1) document the rupture history of the ~45-km-long southwestern section of the Cheraw...
Data Release for Luminescence: Luminescence data for Natural Trap Cave, Wyoming
The following report summarizes the dating results from the Natural Trap Cave 2018-2019 dating project. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating-related calculations. We recommend that this report be included...
Data Release for Luminescence: Floodplain Sediment Storage Timescales of the Laterally Confined Meandering Powder River, U.S.A
The following report summarizes the dating results from the. Within this report, we detail the methodology used to determine the storage time distribution for a 17 km length of Powder River in Montana, U.S.A. by the age distribution of eroded sediment. This data is used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence...
Data release for luminescence: Edwards Air Force Base (CA) and CA Water Science Center report including luminescence data and ages
The following report summarizes the dating results from Aeolian deposits within and around Edwards Air Force Base in California. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and dating related calculations. We recommend that...
Bringing the South Dakota southern Black Hills Mammoth Site formation and fossil discovery to light: a chronological reassignment using Luminescence Dating
The Mammoth Springs (MS) fossil site at Hot Springs, South Dakota, provides a unique opportunity to reconstruct paleoenvironmental conditions. We used luminescence dating on fine sand sized potassium feldspars to establish a chronological framework for the site. In addition, we dated a late Pleistocene paludal proxy site using luminescence and incorporated those results with previous...
Geologic setting and geomorphic history of the La Botica area, south-central Colorado
La Botica is positioned on a topographic bench sharply inset into the gentle eastern slope of the high San Juan Mountains and perched ~70-80 meters above La Jara Creek (fig. 1), a tributary to the Rio Grande. Quaternary surface processes have modified the Tertiary bedrock deposits that underlie La Botica to shape the physical environment. Bedrock deposits consist of Oligocene to Pliocene...
Optically Stimulated Luminescence (OSL) data and ages for selected Native American Sacred Ceremonial Stone Landscape features--Final Project Report Submitted to the Narragansett Tribal Historic Preservation Trust
Stone rows, enclosures, structures and chambers can be found in the landscapes of Massachusetts and Rhode Island. Structures similar to those shown in the cover photo are documented elsewhere. The age, cultural affiliation, and purpose of these stone structures--which are found in a variety of forms, such as piles arranged in spatial configurations across landscapes, shapes suggesting...
DATA RELEASE Part 2: Optical luminescence dating of Bradley Lake, Oregon, tsunami deposits, analytical data for: A maximum rupture model for the central and southern Cascadia subduction zone-reassessing ages for coastal evidence of megathrust earthquakes
The following report summarizes the dating results from Bradley Lake, Oregon. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and datingrelated calculations. We recommend that this report be included as the supplementary...
Data release for application of a luminescence-based sediment transport model
This data release contains luminescence data from the manuscript "Application of a luminescence-based sediment transport model" by Gray et al. It contains data from the luminescence measurements and experiments in the paper.
OSL methods and field and laboratory data for Mesa Verde soils to support journal article
Thin loess deposits on the uplands of the southeastern Colorado Plateau have previously not been well studied. We sampled deposits and soils from trenches on Hatch Point mesa near Canyonlands National Park, Utah, and from two outcrops in Mesa Verde National Park, Colorado. At Hatch Point, the oldest buried unit yielded two OSL ages of 10,370 and 7,555 yr; the middle unit yielded 10 OSL...
Filter Total Items: 15
*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