Articles | Volume 4, issue 1
https://doi.org/10.5194/gchron-4-191-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gchron-4-191-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
07 Apr 2022
Research article |
| 07 Apr 2022
| 07 Apr 2022
Cosmogenic ages indicate no MIS 2 refugia in the Alexander Archipelago, Alaska
Department of Geology, University at Buffalo, Buffalo, NY 14260, USA
Jason P. Briner
Department of Geology, University at Buffalo, Buffalo, NY 14260, USA
James F. Baichtal
Tongass National Forest, Thorne Bay, AK 99919, USA
Alia J. Lesnek
School of Earth and Environmental Sciences, CUNY Queens College,
Flushing, NY 11367, USA
Joseph M. Licciardi
Department of Earth Sciences, University of New Hampshire, Durham, NH 03824, USA
Related authors
Karlee K. Prince, Jason P. Briner, Caleb K. Walcott, Brooke M. Chase, Andrew L. Kozlowski, Tammy M. Rittenour, and Erica P. Yang
EGUsphere, https://doi.org/10.5194/egusphere-2023-2655, https://doi.org/10.5194/egusphere-2023-2655, 2024
Short summary
Short summary
We date Laurentide Ice Sheet retreat after the Last Glacial Maximum in western New York, USA. We apply radiocarbon and optically stimulated luminesce dating to glacial features. We find that ice began retreating shortly after 20 ka, but hummocky moraine stabilization is delayed until climate warming at ~15–14 ka.
Caleb K. Walcott, Jason P. Briner, Joseph P. Tulenko, and Stuart M. Evans
Clim. Past, 20, 91–106, https://doi.org/10.5194/cp-20-91-2024, https://doi.org/10.5194/cp-20-91-2024, 2024
Short summary
Short summary
Available data suggest that Alaska was not as cold as many of the high-latitude areas of the Northern Hemisphere during the Last Ice Age. These results come from isolated climate records, climate models, and data synthesis projects. We used the extents of mountain glaciers during the Last Ice Age and Little Ice Age to show precipitation gradients across Alaska and provide temperature data from across the whole state. Our findings support a relatively warm Alaska during the Last Ice Age.
Jason P. Briner, Caleb K. Walcott, Joerg M. Schaefer, Nicolás E. Young, Joseph A. MacGregor, Kristin Poinar, Benjamin A. Keisling, Sridhar Anandakrishnan, Mary R. Albert, Tanner Kuhl, and Grant Boeckmann
The Cryosphere, 16, 3933–3948, https://doi.org/10.5194/tc-16-3933-2022, https://doi.org/10.5194/tc-16-3933-2022, 2022
Short summary
Short summary
The 7.4 m of sea level equivalent stored as Greenland ice is getting smaller every year. The uncertain trajectory of ice loss could be better understood with knowledge of the ice sheet's response to past climate change. Within the bedrock below the present-day ice sheet is an archive of past ice-sheet history. We analyze all available data from Greenland to create maps showing where on the ice sheet scientists can drill, using currently available drills, to obtain sub-ice materials.
Joseph P. Tulenko, Jason P. Briner, Nicolás E. Young, and Joerg M. Schaefer
Clim. Past, 20, 625–636, https://doi.org/10.5194/cp-20-625-2024, https://doi.org/10.5194/cp-20-625-2024, 2024
Short summary
Short summary
We take advantage of a site in Alaska – where climate records are limited and a former alpine glacier deposited a dense sequence of moraines spanning the full deglaciation – to construct a proxy summer temperature record. Building on age constraints for moraines in the valley, we reconstruct paleo-glacier surfaces and estimate the summer temperatures (relative to the Little Ice Age) for each moraine. The record suggests that the influence of North Atlantic climate forcing extended to Alaska.
Alia Lesnek, Joseph M. Licciardi, Alan J. Hidy, and Tyler S. Anderson
EGUsphere, https://doi.org/10.5194/egusphere-2024-713, https://doi.org/10.5194/egusphere-2024-713, 2024
Short summary
Short summary
We present an improved workflow for extracting and measuring chlorine isotopes in rocks and minerals. Experiments on seven geologic samples demonstrate that our workflow provides reliable results while offering several distinct advantages over traditional methods. Most notably, our workflow reduces the amount of isotopically enriched chlorine spike used per rock sample by up to 95 %, which will allow researchers to analyze more samples using their existing laboratory supplies.
Karlee K. Prince, Jason P. Briner, Caleb K. Walcott, Brooke M. Chase, Andrew L. Kozlowski, Tammy M. Rittenour, and Erica P. Yang
EGUsphere, https://doi.org/10.5194/egusphere-2023-2655, https://doi.org/10.5194/egusphere-2023-2655, 2024
Short summary
Short summary
We date Laurentide Ice Sheet retreat after the Last Glacial Maximum in western New York, USA. We apply radiocarbon and optically stimulated luminesce dating to glacial features. We find that ice began retreating shortly after 20 ka, but hummocky moraine stabilization is delayed until climate warming at ~15–14 ka.
Caleb K. Walcott, Jason P. Briner, Joseph P. Tulenko, and Stuart M. Evans
Clim. Past, 20, 91–106, https://doi.org/10.5194/cp-20-91-2024, https://doi.org/10.5194/cp-20-91-2024, 2024
Short summary
Short summary
Available data suggest that Alaska was not as cold as many of the high-latitude areas of the Northern Hemisphere during the Last Ice Age. These results come from isolated climate records, climate models, and data synthesis projects. We used the extents of mountain glaciers during the Last Ice Age and Little Ice Age to show precipitation gradients across Alaska and provide temperature data from across the whole state. Our findings support a relatively warm Alaska during the Last Ice Age.
Gifford H. Miller, Simon L. Pendleton, Alexandra Jahn, Yafang Zhong, John T. Andrews, Scott J. Lehman, Jason P. Briner, Jonathan H. Raberg, Helga Bueltmann, Martha Raynolds, Áslaug Geirsdóttir, and John R. Southon
Clim. Past, 19, 2341–2360, https://doi.org/10.5194/cp-19-2341-2023, https://doi.org/10.5194/cp-19-2341-2023, 2023
Short summary
Short summary
Receding Arctic ice caps reveal moss killed by earlier ice expansions; 186 moss kill dates from 71 ice caps cluster at 250–450, 850–1000 and 1240–1500 CE and continued expanding 1500–1880 CE, as recorded by regions of sparse vegetation cover, when ice caps covered > 11 000 km2 but < 100 km2 at present. The 1880 CE state approached conditions expected during the start of an ice age; climate models suggest this was only reversed by anthropogenic alterations to the planetary energy balance.
Brandon L. Graham, Jason P. Briner, Nicolás E. Young, Allie Balter-Kennedy, Michele Koppes, Joerg M. Schaefer, Kristin Poinar, and Elizabeth K. Thomas
The Cryosphere, 17, 4535–4547, https://doi.org/10.5194/tc-17-4535-2023, https://doi.org/10.5194/tc-17-4535-2023, 2023
Short summary
Short summary
Glacial erosion is a fundamental process operating on Earth's surface. Two processes of glacial erosion, abrasion and plucking, are poorly understood. We reconstructed rates of abrasion and quarrying in Greenland. We derive a total glacial erosion rate of 0.26 ± 0.16 mm per year. We also learned that erosion via these two processes is about equal. Because the site is similar to many other areas covered by continental ice sheets, these results may be applied to many places on Earth.
Jason P. Briner, Caleb K. Walcott, Joerg M. Schaefer, Nicolás E. Young, Joseph A. MacGregor, Kristin Poinar, Benjamin A. Keisling, Sridhar Anandakrishnan, Mary R. Albert, Tanner Kuhl, and Grant Boeckmann
The Cryosphere, 16, 3933–3948, https://doi.org/10.5194/tc-16-3933-2022, https://doi.org/10.5194/tc-16-3933-2022, 2022
Short summary
Short summary
The 7.4 m of sea level equivalent stored as Greenland ice is getting smaller every year. The uncertain trajectory of ice loss could be better understood with knowledge of the ice sheet's response to past climate change. Within the bedrock below the present-day ice sheet is an archive of past ice-sheet history. We analyze all available data from Greenland to create maps showing where on the ice sheet scientists can drill, using currently available drills, to obtain sub-ice materials.
Joshua K. Cuzzone, Nicolás E. Young, Mathieu Morlighem, Jason P. Briner, and Nicole-Jeanne Schlegel
The Cryosphere, 16, 2355–2372, https://doi.org/10.5194/tc-16-2355-2022, https://doi.org/10.5194/tc-16-2355-2022, 2022
Short summary
Short summary
We use an ice sheet model to determine what influenced the Greenland Ice Sheet to retreat across a portion of southwestern Greenland during the Holocene (about the last 12 000 years). Our simulations, constrained by observations from geologic markers, show that atmospheric warming and ice melt primarily caused the ice sheet to retreat rapidly across this domain. We find, however, that iceberg calving at the interface where the ice meets the ocean significantly influenced ice mass change.
Douglas P. Steen, Joseph S. Stoner, Jason P. Briner, and Darrell S. Kaufman
Geochronology Discuss., https://doi.org/10.5194/gchron-2021-19, https://doi.org/10.5194/gchron-2021-19, 2021
Publication in GChron not foreseen
Short summary
Short summary
Paleomagnetic data from Cascade Lake (Brooks Range, Alaska) extend the radiometric-based age model of the sedimentary sequence extending back 21 kyr. Correlated ages based on prominent features in paleomagnetic secular variations (PSV) diverge from the radiometric ages in the upper 1.6 m, by up to about 2000 years at around 4 ka. Four late Holocene cryptotephra in this section support the PSV chronology and suggest the influence of hard water or aged organic material.
Svend Funder, Anita H. L. Sørensen, Nicolaj K. Larsen, Anders A. Bjørk, Jason P. Briner, Jesper Olsen, Anders Schomacker, Laura B. Levy, and Kurt H. Kjær
Clim. Past, 17, 587–601, https://doi.org/10.5194/cp-17-587-2021, https://doi.org/10.5194/cp-17-587-2021, 2021
Short summary
Short summary
Cosmogenic 10Be exposure dates from outlying islets along 300 km of the SW Greenland coast indicate that, although affected by inherited 10Be, the ice margin here was retreating during the Younger Dryas. These results seem to be corroborated by recent studies elsewhere in Greenland. The apparent mismatch between temperatures and ice margin behaviour may be explained by the advection of warm water to the ice margin on the shelf and by increased seasonality, both caused by a weakened AMOC.
Nicolás E. Young, Alia J. Lesnek, Josh K. Cuzzone, Jason P. Briner, Jessica A. Badgeley, Alexandra Balter-Kennedy, Brandon L. Graham, Allison Cluett, Jennifer L. Lamp, Roseanne Schwartz, Thibaut Tuna, Edouard Bard, Marc W. Caffee, Susan R. H. Zimmerman, and Joerg M. Schaefer
Clim. Past, 17, 419–450, https://doi.org/10.5194/cp-17-419-2021, https://doi.org/10.5194/cp-17-419-2021, 2021
Short summary
Short summary
Retreat of the Greenland Ice Sheet (GrIS) margin is exposing a bedrock landscape that holds clues regarding the timing and extent of past ice-sheet minima. We present cosmogenic nuclide measurements from recently deglaciated bedrock surfaces (the last few decades), combined with a refined chronology of southwestern Greenland deglaciation and model simulations of GrIS change. Results suggest that inland retreat of the southwestern GrIS margin was likely minimal in the middle to late Holocene.
Joseph P. Tulenko, William Caffee, Avriel D. Schweinsberg, Jason P. Briner, and Eric M. Leonard
Geochronology, 2, 245–255, https://doi.org/10.5194/gchron-2-245-2020, https://doi.org/10.5194/gchron-2-245-2020, 2020
Short summary
Short summary
We investigate the timing and rate of retreat for three alpine glaciers in the southern Rocky Mountains to test whether they followed the pattern of global climate change or were majorly influenced by regional forcing mechanisms. We find that the latter is most likely for these glaciers. Our conclusions are based on a new 10Be chronology of alpine glacier retreat. We quantify retreat rates for each valley using the BACON program in R, which may be of interest for the audience of Geochronology.
Jacob Downs, Jesse Johnson, Jason Briner, Nicolás Young, Alia Lesnek, and Josh Cuzzone
The Cryosphere, 14, 1121–1137, https://doi.org/10.5194/tc-14-1121-2020, https://doi.org/10.5194/tc-14-1121-2020, 2020
Short summary
Short summary
We use an inverse modeling approach based on the unscented transform (UT) and a new reconstruction of Holocene ice sheet retreat in western central Greenland to infer precipitation changes throughout the Holocene. Our results indicate that warming during the Holocene Thermal Maximum (HTM) was linked to elevated snowfall that slowed retreat despite high temperatures. We also find that the UT provides a computationally inexpensive approach to Bayesian inversion and uncertainty quantification.
Joshua K. Cuzzone, Nicole-Jeanne Schlegel, Mathieu Morlighem, Eric Larour, Jason P. Briner, Helene Seroussi, and Lambert Caron
The Cryosphere, 13, 879–893, https://doi.org/10.5194/tc-13-879-2019, https://doi.org/10.5194/tc-13-879-2019, 2019
Short summary
Short summary
We present ice sheet modeling results of ice retreat over southwestern Greenland during the last 12 000 years, and we also test the impact that model horizontal resolution has on differences in the simulated spatial retreat and its associated rate. Results indicate that model resolution plays a minor role in simulated retreat in areas where bed topography is not complex but plays an important role in areas where bed topography is complex (such as fjords).
Related subject area
Cosmogenic nuclide dating
Regional beryllium-10 production rate for the mid-elevation mountainous regions in central Europe, deduced from a multi-method study of moraines and lake sediments in the Black Forest
Technical note: Optimizing the in situ cosmogenic 36Cl extraction and measurement workflow for geologic applications
Production rate calibration for cosmogenic 10Be in pyroxene by applying a rapid fusion method to 10Be-saturated samples from the Transantarctic Mountains, Antarctica
Short communication: Cosmogenic noble gas depletion in soils by wildfire heating
Cosmogenic 3He chronology of postglacial lava flows at Mt. Ruapehu, New Zealand
Last ice sheet recession and landscape emergence above sea level in east-central Sweden, evaluated using in situ cosmogenic 14C from quartz
Early Holocene ice retreat from Isle Royale in the Laurentian Great Lakes constrained with 10Be exposure-age dating
Technical note: Studying lithium metaborate fluxes and extraction protocols with a new, fully automated in situ cosmogenic 14C processing system at PRIME Lab
Cosmogenic 10Be in pyroxene: laboratory progress, production rate systematics, and application of the 10Be–3He nuclide pair in the Antarctic Dry Valleys
Technical note: A software framework for calculating compositionally dependent in situ 14C production rates
10Be age control of glaciation in the Beartooth Mountains, USA, from the latest Pleistocene through the Holocene
Constraining the aggradation mode of Pleistocene river deposits based on cosmogenic radionuclide depth profiling and numerical modelling
Technical note: Evaluating a geographical information system (GIS)-based approach for determining topographic shielding factors in cosmic-ray exposure dating
Combined linear-regression and Monte Carlo approach to modeling exposure age depth profiles
Cosmogenic nuclide weathering biases: corrections and potential for denudation and weathering rate measurements
Cosmogenic nuclide and solute flux data from central Cuban rivers emphasize the importance of both physical and chemical mass loss from tropical landscapes
Technical note: Accelerator mass spectrometry of 10Be and 26Al at low nuclide concentrations
Reconciling the apparent absence of a Last Glacial Maximum alpine glacial advance, Yukon Territory, Canada, through cosmogenic beryllium-10 and carbon-14 measurements
In situ-produced cosmogenic krypton in zircon and its potential for Earth surface applications
Cosmogenic nuclide exposure age scatter records glacial history and processes in McMurdo Sound, Antarctica
Technical Note: Noble gas extraction procedure and performance of the Cologne Helix MC Plus multi-collector noble gas mass spectrometer for cosmogenic neon isotope analysis
Exposure dating of detrital magnetite using 3He enabled by microCT and calibration of the cosmogenic 3He production rate in magnetite
Calibrating a long-term meteoric 10Be delivery rate into eroding western US glacial deposits by comparing meteoric and in situ produced 10Be depth profiles
Delayed and rapid deglaciation of alpine valleys in the Sawatch Range, southern Rocky Mountains, USA
Technical note: A prototype transparent-middle-layer data management and analysis infrastructure for cosmogenic-nuclide exposure dating
Isolation of quartz for cosmogenic in situ 14C analysis
Chlorine-36∕beryllium-10 burial dating of alluvial fan sediments associated with the Mission Creek strand of the San Andreas Fault system, California, USA
Felix Martin Hofmann, Claire Rambeau, Lukas Gegg, Melanie Schulz, Martin Steiner, Alexander Fülling, Laëtitia Léanni, Frank Preusser, and ASTER Team
Geochronology, 6, 147–174, https://doi.org/10.5194/gchron-6-147-2024, https://doi.org/10.5194/gchron-6-147-2024, 2024
Short summary
Short summary
We determined 10Be concentrations in moraine boulder surfaces in the southern Black Forest, SW Germany. We applied three independent dating methods to younger lake sediments. With the aid of independent age datasets, we calculated the growth of 10Be concentrations in moraine boulder surfaces.
Alia Lesnek, Joseph M. Licciardi, Alan J. Hidy, and Tyler S. Anderson
EGUsphere, https://doi.org/10.5194/egusphere-2024-713, https://doi.org/10.5194/egusphere-2024-713, 2024
Short summary
Short summary
We present an improved workflow for extracting and measuring chlorine isotopes in rocks and minerals. Experiments on seven geologic samples demonstrate that our workflow provides reliable results while offering several distinct advantages over traditional methods. Most notably, our workflow reduces the amount of isotopically enriched chlorine spike used per rock sample by up to 95 %, which will allow researchers to analyze more samples using their existing laboratory supplies.
Marie Bergelin, Greg Balco, Lee B. Corbett, and Paul R. Bierman
EGUsphere, https://doi.org/10.5194/egusphere-2024-702, https://doi.org/10.5194/egusphere-2024-702, 2024
Short summary
Short summary
Cosmogenic nuclides, such as 10Be, are rare isotopes produced in rocks when exposed at Earth’s surface and are valuable for understanding surface processes and landscape evolution. However, 10Be is usually measured in quartz minerals. Here we present advances in efficiently extracting and measuring 10Be in the pyroxene mineral. These measurements expand the use of 10Be as a dating tool for new rock types and provide opportunities to understand landscape processes in areas that lack quartz.
Greg Balco, Alan J. Hidy, William T. Struble, and Joshua J. Roering
Geochronology, 6, 71–76, https://doi.org/10.5194/gchron-6-71-2024, https://doi.org/10.5194/gchron-6-71-2024, 2024
Short summary
Short summary
We describe a new method of reconstructing the long-term, pre-observational frequency and/or intensity of wildfires in forested landscapes using trace concentrations of the noble gases helium and neon that are formed in soil mineral grains by cosmic-ray bombardment of the Earth's surface.
Pedro Doll, Shaun Robert Eaves, Ben Matthew Kennedy, Pierre-Henri Blard, Alexander Robert Lee Nichols, Graham Sloan Leonard, Dougal Bruce Townsend, Jim William Cole, Chris Edward Conway, Sacha Baldwin, Gabriel Fénisse, Laurent Zimmermann, and Bouchaïb Tibari
EGUsphere, https://doi.org/10.5194/egusphere-2024-163, https://doi.org/10.5194/egusphere-2024-163, 2024
Short summary
Short summary
In this study, we use cosmogenic-sourced 3He to determine the eruption ages of 23 lava flows at Mt. Ruapehu, New Zealand, and we show how this method can help overcome challenges associated with traditional dating methods in young lavas. Comparison with other methods demonstrates the accuracy of our data, and the method's reliability. The new eruption ages allowed us to identify periods of quasi-simultaneous activity from different volcanic vents during the last 20,000 years.
Bradley W. Goodfellow, Arjen P. Stroeven, Nathaniel A. Lifton, Jakob Heyman, Alexander Lewerentz, Kristina Hippe, Jens-Ove Näslund, and Marc W. Caffee
EGUsphere, https://doi.org/10.5194/egusphere-2023-2821, https://doi.org/10.5194/egusphere-2023-2821, 2023
Short summary
Short summary
Carbon-14 produced in quartz provides a new tool to date exposure of bedrock surfaces. Samples from ten exposed bedrock surfaces in east central Sweden give dates consistent both with the timing of landscape emergence above sea level through postglacial rebound and retreat of the last ice sheet shown in previous reconstructions. Carbon-14 in quartz (half-life 5700 ± 30 years) can therefore be used for dating in landscapes where isotopes with longer half-lives give complex exposure results.
Eric W. Portenga, David J. Ullman, Lee B. Corbett, Paul R. Bierman, and Marc W. Caffee
Geochronology, 5, 413–431, https://doi.org/10.5194/gchron-5-413-2023, https://doi.org/10.5194/gchron-5-413-2023, 2023
Short summary
Short summary
New exposure ages of glacial erratics on moraines on Isle Royale – the largest island in North America's Lake Superior – show that the Laurentide Ice Sheet did not retreat from the island nor the south shores of Lake Superior until the early Holocene, which is later than previously thought. These new ages unify regional ice retreat histories from the mainland, the Lake Superior lake-bottom stratigraphy, underwater moraines, and meltwater drainage pathways through the Laurentian Great Lakes.
Nathaniel Lifton, Jim Wilson, and Allie Koester
Geochronology, 5, 361–375, https://doi.org/10.5194/gchron-5-361-2023, https://doi.org/10.5194/gchron-5-361-2023, 2023
Short summary
Short summary
We describe a new, fully automated extraction system for in situ 14C at PRIME Lab that incorporates more reliable components and designs than our original systems. We use a LiBO2 flux to dissolve a quartz sample in oxygen after removing contaminant 14C with a lower-temperature combustion step. Experiments with new Pt/Rh sample boats demonstrated reduced procedural blanks, and analyses of well-characterized intercomparison materials tested the effects of process variables on 14C yields.
Allie Balter-Kennedy, Joerg M. Schaefer, Roseanne Schwartz, Jennifer L. Lamp, Laura Penrose, Jennifer Middleton, Jean Hanley, Bouchaïb Tibari, Pierre-Henri Blard, Gisela Winckler, Alan J. Hidy, and Greg Balco
Geochronology, 5, 301–321, https://doi.org/10.5194/gchron-5-301-2023, https://doi.org/10.5194/gchron-5-301-2023, 2023
Short summary
Short summary
Cosmogenic nuclides like 10Be are rare isotopes created in rocks exposed at the Earth’s surface and can be used to understand glacier histories and landscape evolution. 10Be is usually measured in the mineral quartz. Here, we show that 10Be can be reliably measured in the mineral pyroxene. We use the measurements to determine exposure ages and understand landscape processes in rocks from Antarctica that do not have quartz, expanding the use of this method to new rock types.
Alexandria J. Koester and Nathaniel A. Lifton
Geochronology, 5, 21–33, https://doi.org/10.5194/gchron-5-21-2023, https://doi.org/10.5194/gchron-5-21-2023, 2023
Short summary
Short summary
In situ 14C’s short half-life (5.7 kyr) is unique among cosmogenic nuclides, making it sensitive to complex exposure and burial histories since 25 ka. Current extraction methods focus on quartz, but the ability to extract it from other minerals would expand applications. We developed MATLAB® scripts to calculate in situ 14C production rates from a broad range of mineral compositions. Results confirm O, Si, Al, and Mg as key targets but also find significant production from Na for the first time.
Aaron M. Barth, Elizabeth G. Ceperley, Claire Vavrus, Shaun A. Marcott, Jeremy D. Shakun, and Marc W. Caffee
Geochronology, 4, 731–743, https://doi.org/10.5194/gchron-4-731-2022, https://doi.org/10.5194/gchron-4-731-2022, 2022
Short summary
Short summary
Deposits left behind by past glacial activity provide insight into the previous size and behavior of glaciers and act as another line of evidence for past climate. Here we present new age control for glacial deposits in the mountains of Montana and Wyoming, United States. While some deposits indicate glacial activity within the last 2000 years, others are shown to be older than previously thought, thus redefining the extent of regional Holocene glaciation.
Nathan Vandermaelen, Koen Beerten, François Clapuyt, Marcus Christl, and Veerle Vanacker
Geochronology, 4, 713–730, https://doi.org/10.5194/gchron-4-713-2022, https://doi.org/10.5194/gchron-4-713-2022, 2022
Short summary
Short summary
We constrained deposition phases of fluvial sediments (NE Belgium) over the last 1 Myr with analysis and modelling of rare isotopes accumulation within sediments, occurring as a function of time and inverse function of depth. They allowed the determination of three superposed deposition phases and intercalated non-deposition periods of ~ 40 kyr each. These phases correspond to 20 % of the sediment age, which highlights the importance of considering deposition phase when dating fluvial sediments.
Felix Martin Hofmann
Geochronology, 4, 691–712, https://doi.org/10.5194/gchron-4-691-2022, https://doi.org/10.5194/gchron-4-691-2022, 2022
Short summary
Short summary
If topographical obstructions are present in the surroundings of sampling sites, exposure ages of rock surfaces need to be corrected. A toolbox for the ESRI ArcGIS software allows for quantifying topographic shielding with a digital elevation model, but it has only been validated with few field data. In this study, the output of the toolbox is evaluated with a more extensive dataset. If suitable elevation data are chosen, the toolbox provides a sound approach to determine topographic shielding.
Yiran Wang and Michael E. Oskin
Geochronology, 4, 533–549, https://doi.org/10.5194/gchron-4-533-2022, https://doi.org/10.5194/gchron-4-533-2022, 2022
Short summary
Short summary
When first introduced together with the depth profile technique to determine the surface exposure age, the linear inversion approach has suffered with the drawbacks of not incorporating erosion and muons into calculation. In this paper, we increase the accuracy and applicability of the linear inversion approach by fully considering surface erosion, muogenic production, and radioactive decay, while maintaining its advantage of being straightforward to determine an exposure age.
Richard F. Ott, Sean F. Gallen, and Darryl E. Granger
Geochronology, 4, 455–470, https://doi.org/10.5194/gchron-4-455-2022, https://doi.org/10.5194/gchron-4-455-2022, 2022
Short summary
Short summary
Cosmogenic nuclides are a tool to quantify denudation – the total removal of mass from near the Earth's surface. Chemical weathering can introduce biases to cosmogenic-nuclide-based denudation rates measurements. Here, we investigate the effects of weathering on cosmogenic nuclides and develop tools to correct for this influence. Our results highlight which additional measurements are required to determine accurate denudation rates in regions where weathering is not negligible.
Mae Kate Campbell, Paul R. Bierman, Amanda H. Schmidt, Rita Sibello Hernández, Alejandro García-Moya, Lee B. Corbett, Alan J. Hidy, Héctor Cartas Águila, Aniel Guillén Arruebarrena, Greg Balco, David Dethier, and Marc Caffee
Geochronology, 4, 435–453, https://doi.org/10.5194/gchron-4-435-2022, https://doi.org/10.5194/gchron-4-435-2022, 2022
Short summary
Short summary
We used cosmogenic radionuclides in detrital river sediment to measure erosion rates of watersheds in central Cuba; erosion rates are lower than rock dissolution rates in lowland watersheds. Data from two different cosmogenic nuclides suggest that some basins may have a mixed layer deeper than is typically modeled and could have experienced significant burial after or during exposure. We conclude that significant mass loss may occur at depth through chemical weathering processes.
Klaus M. Wilcken, Alexandru T. Codilean, Réka-H. Fülöp, Steven Kotevski, Anna H. Rood, Dylan H. Rood, Alexander J. Seal, and Krista Simon
Geochronology, 4, 339–352, https://doi.org/10.5194/gchron-4-339-2022, https://doi.org/10.5194/gchron-4-339-2022, 2022
Short summary
Short summary
Cosmogenic nuclides are now widely applied in the Earth sciences; however, more recent applications often push the analytical limits of the technique. Our study presents a comprehensive method for analysis of cosmogenic 10Be and 26Al samples down to isotope concentrations of a few thousand atoms per gram of sample, which opens the door to new and more varied applications of cosmogenic nuclide analysis.
Brent M. Goehring, Brian Menounos, Gerald Osborn, Adam Hawkins, and Brent Ward
Geochronology, 4, 311–322, https://doi.org/10.5194/gchron-4-311-2022, https://doi.org/10.5194/gchron-4-311-2022, 2022
Short summary
Short summary
We explored surface exposure dating with two nuclides to date two sets of moraines from the Yukon Territory and explain the reasoning for the observed ages. Results suggest multiple processes, including preservation of nuclides from a prior exposure period, and later erosion of the moraines is required to explain the data. Our results only allow for the older moraines to date to Marine Isotope Stage 3 or 4 and the younger moraines to date to the very earliest Holocene.
Tibor János Dunai, Steven Andrew Binnie, and Axel Gerdes
Geochronology, 4, 65–85, https://doi.org/10.5194/gchron-4-65-2022, https://doi.org/10.5194/gchron-4-65-2022, 2022
Short summary
Short summary
We develop in situ-produced terrestrial cosmogenic krypton as a new tool to date and quantify Earth surface processes, the motivation being the availability of six stable isotopes and one radioactive isotope (81Kr, half-life 229 kyr) and of an extremely weathering-resistant target mineral (zircon). We provide proof of principle that terrestrial Krit can be quantified and used to unravel Earth surface processes.
Andrew J. Christ, Paul R. Bierman, Jennifer L. Lamp, Joerg M. Schaefer, and Gisela Winckler
Geochronology, 3, 505–523, https://doi.org/10.5194/gchron-3-505-2021, https://doi.org/10.5194/gchron-3-505-2021, 2021
Short summary
Short summary
Cosmogenic nuclide surface exposure dating is commonly used to constrain the timing of past glacier extents. However, Antarctic exposure age datasets are often scattered and difficult to interpret. We compile new and existing exposure ages of a glacial deposit with independently known age constraints and identify surface processes that increase or reduce the likelihood of exposure age scatter. Then we present new data for a previously unmapped and undated older deposit from the same region.
Benedikt Ritter, Andreas Vogt, and Tibor J. Dunai
Geochronology, 3, 421–431, https://doi.org/10.5194/gchron-3-421-2021, https://doi.org/10.5194/gchron-3-421-2021, 2021
Short summary
Short summary
We describe the design and performance of a new noble gas mass laboratory dedicated to the development of and application to cosmogenic nuclides at the University of Cologne (Germany). At the core of the laboratory are a state-of-the-art high-mass-resolution multicollector Helix MCPlus (Thermo-Fisher) noble gas mass spectrometer and a novel custom-designed automated extraction line, including a laser-powered extraction furnace. Performance was tested with intercomparison (CREU-1) material.
Florian Hofmann, Emily H. G. Cooperdock, A. Joshua West, Dominic Hildebrandt, Kathrin Strößner, and Kenneth A. Farley
Geochronology, 3, 395–414, https://doi.org/10.5194/gchron-3-395-2021, https://doi.org/10.5194/gchron-3-395-2021, 2021
Short summary
Short summary
We use microCT scanning to improve the quality of 3He exposure ages measured in detrital magnetite. We show that the presence of inclusions can significantly increase the measured amount of 3He and thereby the exposure age. By prescreening magnetite with microCT and analyzing only inclusion-free grains, this problem can be avoided. We also calibrate the cosmogenic 3He production rate in magnetite relative to 10Be in quartz, which can be used for similar studies in the future.
Travis Clow, Jane K. Willenbring, Mirjam Schaller, Joel D. Blum, Marcus Christl, Peter W. Kubik, and Friedhelm von Blanckenburg
Geochronology, 2, 411–423, https://doi.org/10.5194/gchron-2-411-2020, https://doi.org/10.5194/gchron-2-411-2020, 2020
Short summary
Short summary
Meteoric beryllium-10 concentrations in soil profiles have great capacity to quantify Earth surface processes, such as erosion rates and landform ages. However, determining these requires an accurate estimate of the delivery rate of this isotope to local sites. Here, we present a new method to constrain the long-term delivery rate to an eroding western US site, compare it against existing delivery rate estimates (revealing considerable disagreement between methods), and suggest best practices.
Joseph P. Tulenko, William Caffee, Avriel D. Schweinsberg, Jason P. Briner, and Eric M. Leonard
Geochronology, 2, 245–255, https://doi.org/10.5194/gchron-2-245-2020, https://doi.org/10.5194/gchron-2-245-2020, 2020
Short summary
Short summary
We investigate the timing and rate of retreat for three alpine glaciers in the southern Rocky Mountains to test whether they followed the pattern of global climate change or were majorly influenced by regional forcing mechanisms. We find that the latter is most likely for these glaciers. Our conclusions are based on a new 10Be chronology of alpine glacier retreat. We quantify retreat rates for each valley using the BACON program in R, which may be of interest for the audience of Geochronology.
Greg Balco
Geochronology, 2, 169–175, https://doi.org/10.5194/gchron-2-169-2020, https://doi.org/10.5194/gchron-2-169-2020, 2020
Short summary
Short summary
Geologic dating methods generally do not directly measure ages. Instead, interpreting a geochemical measurement as an age requires a middle layer of calculations and supporting data, and the fact that this layer continually improves is an obstacle to synoptic analysis of geochronological data. This paper describes a prototype data management and analysis system that addresses this obstacle by making the middle-layer calculations transparent and dynamic to the user.
Keir A. Nichols and Brent M. Goehring
Geochronology, 1, 43–52, https://doi.org/10.5194/gchron-1-43-2019, https://doi.org/10.5194/gchron-1-43-2019, 2019
Short summary
Short summary
We describe observations of anomalously high measurements of C-14 made from geologic material. We undertake a systematic investigation to identify the source of contamination, which we hypothesise is sourced from a commonly used method that is used prior to sample analysis. We find that the method does introduce modern carbon to samples and elevates C-14 measurements. We describe a standard procedure that effectively removes contamination from the aforementioned method.
Greg Balco, Kimberly Blisniuk, and Alan Hidy
Geochronology, 1, 1–16, https://doi.org/10.5194/gchron-1-1-2019, https://doi.org/10.5194/gchron-1-1-2019, 2019
Short summary
Short summary
This article applies a new geochemical dating method to determine the age of sedimentary deposits useful in reconstructing slip rates on a major fault system.
Cited articles
Addison, J. A., Beget, J. E., Ager, T. A., and Finney, B. P.: Marine tephrochronology of the Mt. Edgecumbe volcanic field, southeast Alaska, USA, Quaternary Res., 73, 277–292, https://doi.org/10.1016/j.yqres.2009.10.007, 2010.
Ager, T. A.: Late Quaternary vegetation development following deglaciation
of northwestern Alexander Archipelago, Alaska, Front. Earth Sci.,
7, 104, https://doi.org/10.3389/feart.2019.00104, 2019.
Baichtal, J. F., Lesnek, A. J., Carlson, R. J., Schmuck, N., Smith, J. L.,
Landwehr, D. J., and Briner, J. P.: Late Pleistocene and Early Holocene Sea
level History Glacial Retreat Interpreted from Shell-bearing Marine Deposits
of Southeastern Alaska, Geosphere, 17, 1590–1615, https://doi.org/10.1130/GES02359.1, 2021.
Balco, G.: Production rate calculations for cosmic-ray-muon-produced 10Be and 26Al benchmarked against geological calibration data, Quat. Geochronol., 39, 150–173, 2017.
Balco, G.: Technical note: A prototype transparent-middle-layer data management and analysis infrastructure for cosmogenic-nuclide exposure dating, Geochronology, 2, 169–175, https://doi.org/10.5194/gchron-2-169-2020, 2020.
Balco, G., Stone, J. O., Lifton, N. A., and Dunai, T. J.: A complete and
easily accessible means of calculating surface exposure ages or erosion
rates from 10Be and 26Al measurements, Quat. Geochronol., 3, 174–195, https://doi.org/10.1016/j.quageo.2007.12.001, 2008.
Barrie, J. V. and Conway, K. W.: Late Quaternary glaciation and postglacial
stratigraphy of the northern Pacific margin of Canada, Quaternary Res.,
51, 113–123, 1999.
Begét, J. E. and Motyka, R. J.: New dates on late Pleistocene dacitic
tephra from the Mount Edgecumbe volcanic field, southeastern Alaska,
Quaternary Res., 49, 123–125, 1998.
Blaise, B., Clague, J. J., and Mathewes, R. W.: Time of maximum Late
Wisconsin glaciation, West Coast of Canada, Quaternary Res., 34,
282–295, https://doi.org/10.1016/0033-5894(90)90041-I, 1990.
Booth, D. B., Troost, K. G., Clague, J. J., and Waitt, R. B.: The
Cordilleran ice sheet, Developments in Quaternary Sciences, 1, 17–43, 2003.
Borchers, B., Marrero, S., Balco, G., Caffee, M., Goehring, B., Lifton, N.,
Nishiizumi, K., Phillips, F., Schaefer, J., and Stone, J. J. Q. G.: Geological calibration of spallation production rates in the CRONUS-Earth project, Quat. Geochronol., 31, 188–198, 2016.
Brew, D. A.: Geologic map of the Craig, Dixon Entrance, and parts of the
Ketchikan and Prince Rupert quadrangles, Southeastern Alaska, No. 95-215, https://doi.org/10.3133/ofr95215, 1995.
Briner, J. P. and Swanson, T. W.: Using inherited cosmogenic 36Cl to
constrain glacial erosion rates of the Cordilleran ice sheet, Geology, 26,
3–6, 1998.
Briner, J. P., Goehring, B. M., Mangerud, J., and Svendsen, J. I.: The deep
accumulation of 10Be at Utsira, southwestern Norway: implications for
cosmogenic nuclide exposure dating in peripheral ice sheet landscapes,
Geophys. Res. Lett., 43, 9121–9129, 2016.
Briner, J. P., Tulenko, J. P., Kaufman, D. S., Young, N. E., Baichtal, J.
F., and Lesnek, A.: The last deglaciation of Alaska, Cuadernos de
investigación geográfica/Geographical Research Letters, 43, 429–448,
2017.
Caissie, B. E., Brigham-Grette, J., Lawrence, K. T., Herbert, T. D., and
Cook, M. S.: Last Glacial Maximum to Holocene sea surface conditions at
Umnak Plateau, Bering Sea, as inferred from diatom, alkenone, and stable
isotope records, Paleoceanography, 25, PA1206, https://doi.org/10.1029/2008PA001671, 2010.
Capps, S. R.: Glaciation in Alaska, United States Geological Survey, Reston,
VA, Report 170A, https://doi.org/10.3133/pp170A, 1932.
Carrara, P. E., Ager, T. A., Baichtal, J. F., and VanSistine, D. P.: Map of
glacial limits and possible refugia in the southern Alexander Archipelago,
Alaska, during the late Wisconsin glaciation, United States Geological Survey, Reston, VA, Report 2424, 2003.
Carrara, P. E., Ager, T. A., and Baichtal, J. F.: Possible refugia in the
Alexander Archipelago of southeastern Alaska during the late Wisconsin
glaciation, Can. J. Earth Sci., 44, 229–244, https://doi.org/10.1139/e06-081, 2007.
Clague, J. J., Mathewes, R. W., and Warner, B. G.: Late Quaternary geology of eastern Graham Island, Queen Charlotte Islands, British Columbia, Can. J. Earth Sci., 19, 1786–1795, https://doi.org/10.1139/e82-157, 1982.
Clark, P. U., Dyke, A. S., Shakun, J. D., Carlson, A. E., Clark, J.,
Wohlfarth, B., Mitrovica, J. X., Hostetler, S. W., and McCabe, A. M.: The
last glacial maximum, Science, 325, 710–714, 2009.
Cook, J. A., Bidlack, A. L., Conroy, C. J., Demboski, J. R., Fleming, M. A.,
Runck, A. M., Stone, K. D., and MacDonald, S. O.: A phylogeographic
perspective on endemism in the Alexander Archipelago of southeast Alaska,
Biol. Conserv., 97, 215–227, https://doi.org/10.1016/S0006-3207(00)00114-2, 2001.
Corbett, L. B., Bierman, P. R., and Rood, D. H.: An approach for optimizing
in situ cosmogenic 10Be sample preparation, Quat. Geochronol., 33,
24–34, https://doi.org/10.1016/j.quageo.2016.02.001, 2016.
Cosma, T. N., Hendy, I. L., and Chang, A. S.: Chronological constraints on
Cordilleran Ice Sheet glaciomarine sedimentation from core MD02-2496 off
Vancouver Island (western Canada), Quaternary Sci. Rev., 27, 941–955,
https://doi.org/10.1016/j.quascirev.2008.01.013, 2008.
Dalton, A. S., Margold, M., Stokes, C. R., Tarasov, L., Dyke, A. S., Adams, R. S., Allard, S., Arends, H. E., Atkinson, N., Attig, J. W., Barnett, P. J., Barnett, R. L., Batterson, M., Bernatchez, P., Borns, H. W., Breckenridge, A., Briner, J. P., Brouard, E., Campbell, J. E., Carlson, A. E., Clague, J. J., Curry, B. B., Daigneault, R.-A., Dubé-Loubert, H., Easterbrook, D. J., Franzi, D. A., Friedrich, H. G., Funder, S., Gauthier, M. S., Gowan, A. S., Harris, K. L., Hétu, B., Hooyer, T. S., Jennings, C. E., Johnson, M. D., Kehew, A. E., Kelley, S. E., Kerr, D., King, E. L., Kjeldsen, K. K., Knaeble, A. R., Lajeunesse, P., Lakeman, T. R., Lamothe, M., Larson, P., Lavoie, M., Loope, H. M., Lowell, T. V., Lusardi, B. A., Manz, L., McMartin, I., Nixon, F. C., Occhietti, S., Parkhill, M. A., Piper, D. J. W., Pronk, A. G., Richard, P. J. H., Ridge, J. C., Ross, M., Roy, M., Seaman, A., Shaw, J., Stea, R. R., Teller, J. T., Thompson, W. B., Thorleifson, L. H., Utting, D. J., Veillette, J. J., Ward, B. C., Weddle, T. K., and Wright, H. E.: An updated radiocarbon-based ice margin chronology for the last deglaciation of the North American Ice Sheet Complex, Quaternary Sci. Rev., 234, 106223, https://doi.org/10.1016/j.quascirev.2020.106223, 2020.
Darvill, C. M., Menounos, B., Goehring, B. M., Lian, O. B., and Caffee, M.
W.: Retreat of the western Cordilleran ice sheet margin during the last
deglaciation, Geophys. Res. Lett., 45, 9710–9720, 2018.
Davies, M. H., Mix, A. C., Stoner, J. S., Addison, J. A., Jaeger, J.,
Finney, B., and Wiest, J.: The deglacial transition on the southeastern
Alaska Margin: Meltwater input, sea level rise, marine productivity, and
sedimentary anoxia, Palaeogeogr. Palaeocl., 26, PA2223,
https://doi.org/10.1029/2010pa002051, 2011.
Demboski, J. R., Stone, K. D., and Cook, J. A.: Further perspectives on the
Haida Gwaii glacial refugium, Evolution, 53, 2008–2012,
https://doi.org/10.1111/j.1558-5646.1999.tb04584.x, 1999.
Dyke, A. S.: An outline of North American deglaciation with emphasis on
central and northern Canada, Developments in Quaternary Sciences, 2,
373–424, 2004.
Eberlein, G. D., Churkin, M., Carter, C., Berg, H., and Ovenshine, A.:
Geology of the Craig quadrangle, Alaska, United States Geological Survey, Reston, VA, Report 83-91, https://doi.org/10.3133/ofr8391, 1983.
Faure, G.: Principles of isotope geology, 2nd edition, Wiley, ISBN 978-0471864127, 1986.
Gosse, J. C. and Phillips, F. M.:. Terrestrial in situ cosmogenic nuclides:
theory and application. Quaternary Sci. Rev., 20, 1475–1560, 2001.
Gregoire, L. J., Otto-Bliesner, B., Valdes, P. J., and Ivanovic, R.: Abrupt
Bølling warming and ice saddle collapse contributions to the Meltwater
Pulse 1a rapid sea level rise, Geophys. Res. Lett., 43, 9130–9137,
2016.
Hansen, B. C. S. and Engstrom, D. R.: Vegetation history of Pleasant
Island, southeastern Alaska, since 13 000 yr BP, Quaternary Res., 46,
161–175, 1996.
Hebda, C. F. G., McLaren, D., Mackie, Q., Fedje, D., Pedersen, M. W.,
Willerslev, E., Brown, K. J., and Hebda, R. J.: Late Pleistocene palaeoenvironments and a possible
glacial refugium on northern Vancouver Island, Canada: Evidence for the
viability of early human settlement on the northwest coast of North America,
Quaternary Sci. Rev., 279, 107388, https://doi.org/10.1016/j.quascirev.2022.107388, 2022.
Ivanovic, R. F., Gregoire, L. J., Wickert, A. D., Valdes, P. J., and Burke,
A.: Collapse of the North American ice saddle 14 500 years ago caused
widespread cooling and reduced ocean overturning circulation, Geophys. Res. Lett., 44, 383–392, 2017.
Jones, R. S., Whitehouse, P. L., Bentley, M. J., Small, D., and Dalton, A.
S.: Impact of glacial isostatic adjustment on cosmogenic surface-exposure
dating, Quaternary Sci. Rev., 212, 206–212, 2019.
Kienast, S. S. and McKay, J. L.: Sea surface temperatures in the subarctic
northeast Pacific reflect millennial-scale climate oscillations during the
last 16 kyrs, Geophys. Res. Lett., 28, 1563–1566, 2001.
Lal, D.: Cosmic ray labeling of erosion surfaces: in situ nuclide production
rates and erosion models, Earth Planet. Sc. Lett., 104, 424–439, 1991.
Lesnek, A. J., Briner, J. P., Lindqvist, C., Baichtal, J. F., and Heaton, T.
H.: Deglaciation of the Pacific coastal corridor directly preceded the human
colonization of the Americas, Sci. Adv., 4, eaar5040, https://doi.org/10.1126/sciadv.aar5040, 2018.
Lesnek, A. J., Briner, J. P., Baichtal, J. F., and Lyles, A. S.: New
constraints on the last deglaciation of the Cordilleran Ice Sheet in coastal
Southeast Alaska, Quaternary Res., 96, 140–160, 2020.
Licciardi, J. M., Denoncourt, C. L., and Finkel, R. C.: Cosmogenic 36Cl production rates from Ca spallation in Iceland, Earth Planet. Sci. Lett., 267, 365–377, https://doi.org/10.1016/j.epsl.2007.11.036, 2008.
Maier, E., Zhang, X., Abelmann, A., Gersonde, R., Mulitza, S., Werner, M.,
Méheust, M., Ren, J., Chapligin, B., and Meyer, H.: North Pacific
freshwater events linked to changes in glacial ocean circulation, Nature,
559, 241–245, 2018.
Mann, D.H.: Wisconsin and Holocene glaciation of southeast Alaska, in: Glaciation in Alaska, edited by: Hamilton, T. D., Reed, K. M., and Thorson, R. B., Alaska Geological Society, Anchorage, AK, 237–265, B0018475H8, 1986.
Mann, D. H. and Hamilton, T. D.: Late Pleistocene and Holocene
Paleoenvironments of the Pacific Coast, Quaternary Sci. Rev., 14,
449–471, https://doi.org/10.1016/0277-3791(95)00016-i, 1995.
Mann, D. H. and Peteet, D. M.: Extent and Timing of the Last Glacial
Maximum in Southwestern Alaska, Quaternary Res., 42, 136–148,
https://doi.org/10.1006/qres.1994.1063, 1994.
Marrero, S. M., Phillips, F. M., Caffee, M. W., and Gosse, J. C.: CRONUS-Earth cosmogenic 36Cl calibration, Quat. Geochronol., 31, 199–219, 2016.
Mathewes, R. W. and Clague, J. J.: Paleoecology and ice limits of the early
Fraser glaciation (Marine Isotope Stage 2) on Haida Gwaii, British Columbia,
Canada, Quaternary Res., 88, 277–292, https://doi.org/10.1017/qua.2017.36, 2017.
Menounos, B., Goehring, B. M., Osborn, G., Margold, M., Ward, B., Bond, J.,
Clarke, G. K. C., Clague, J. J., Lakeman, T., Koch, J., Caffee, M. W., Gosse, J., Stroeven, A.
P., Seguinot, J., and Heyman, J.: Cordilleran Ice Sheet mass loss preceded
climate reversals near the Pleistocene Termination, Science, 358, 781–784, https://doi.org/10.1126/science.aan3001, 2017.
Miller, R. D.: Gastineau channel formation: a composite glaciomarine deposit
near Juneau, Alaska, United States Geological Survey, Reston, VA, Bulletin 1394-C, 1973.
Misarti, N., Finney, B. P., Jordan, J. W., Maschner, H. D. G., Addison, J.
A., Shapley, M. D., Krumhardt, A., and Beget, J. E.: Early retreat of the
Alaska Peninsula Glacier Complex and the implications for coastal migrations
of First Americans, Quaternary Sci. Rev., 48, 1–6,
https://doi.org/10.1016/j.quascirev.2012.05.014, 2012.
Molnia, B. F.: Glaciers of North America – Glaciers of Alaska, United States Geological Survey, Reston, VA, Report 1386K, https://doi.org/10.3133/pp1386K, 2008.
Nishiizumi, K., Imamura, M., Caffee, M. W., Southon, J. R., Finkel, R. C.,
and McAninch, J.: Absolute calibration of 10Be AMS standards, Nucl.
Instrum. Meth. B, 258, 403–413, https://doi.org/10.1016/j.nimb.2007.01.297, 2007.
Porter, S. C. and Swanson, T. W.: Radiocarbon age constraints on rates of
advance and retreat of the Puget lobe of the Cordilleran ice sheet during
the last glaciation, Quaternary Res., 50, 205–213, 1998.
Praetorius, S., Mix, A., Jensen, B., Froese, D., Milne, G., Wolhowe, M.,
Addison, J., and Prahl, F.: Interaction between climate, volcanism, and
isostatic rebound in Southeast Alaska during the last deglaciation, Earth Planet. Sc. Lett., 452, 79–89, 2016.
Praetorius, S. K. and Mix, A. C.: Synchronization of North Pacific and
Greenland climates preceded abrupt deglacial warming, Science, 345, 444–448,
2014.
Praetorius, S. K., Mix, A. C., Walczak, M. H., Wolhowe, M. D., Addison, J.
A., and Prahl, F. G.: North Pacific deglacial hypoxic events linked to
abrupt ocean warming, Nature, 527, 362–366, 2015.
Reger, R. D., Pinney, D. S., Burke, R. M., and Wiltse, M. A.: Catalog and
initial analyses of geologic data related to middle to late Quaternary
deposits, Cook Inlet region, Alaska, State of Alaska Division of Geological
and Geophysical Surveys Report of Investigations, 95–96, https://doi.org/10.14509/2520, 1996.
Riehle, J. R.: The Mount Edgecumbe Volcanic Field: A Geologic History, US
Department of Agriculture, Forest Service, Alaska Region, https://avo.alaska.edu/downloads/reference.php?citid=639 (last access: 5 April 2022), 1996.
Riehle, J. R., Brew, D. A., Reed, K. M., and Bartsch-Winkler, S.: Explosive
latest Pleistocene (?) and Holocene activity of the Mount Edgecumbe volcanic field, Alaska, US Geological Survey Circular, 939, 111–114, 1984.
Riehle, J. R., Champion, D. E., Brew, D. A., and Lanphere, M. A.:
Pyroclastic deposits of the Mount Edgecumbe volcanic field, southeast
Alaska: eruptions of a stratified magma chamber, J. Volcanol. Geoth. Res., 53, 117–143, 1992.
Seguinot, J., Khroulev, C., Rogozhina, I., Stroeven, A. P., and Zhang, Q.: The effect of climate forcing on numerical simulations of the Cordilleran ice sheet at the Last Glacial Maximum, The Cryosphere, 8, 1087–1103, https://doi.org/10.5194/tc-8-1087-2014, 2014.
Seguinot, J., Rogozhina, I., Stroeven, A. P., Margold, M., and Kleman, J.: Numerical simulations of the Cordilleran ice sheet through the last glacial cycle, The Cryosphere, 10, 639–664, https://doi.org/10.5194/tc-10-639-2016, 2016.
Shafer, A. B., Cullingham, C. I., Cote, S. D., and Coltman, D. W.: Of
glaciers and refugia: a decade of study sheds new light on the
phylogeography of northwestern North America, Mol. Ecol., 19, 4589–4621, https://doi.org/10.1111/j.1365-294X.2010.04828.x, 2010.
Shafer, A. B. A., White, K. S., Côté, S. D., and Coltman, D. W.:
Deciphering translocations from relicts in Baranof Island mountain goats: is
an endemic genetic lineage at risk?, Conserv. Genet., 12, 1261–1268, https://doi.org/10.1007/s10592-011-0227-8, 2011.
Shakun, J. D., Clark, P. U., He, F., Marcott, S. A., Mix, A. C., Liu, Z.,
Otto-Bliesner, B., Schmittner, A., and Bard, E.: Global warming preceded by
increasing carbon dioxide concentrations during the last deglaciation,
Nature, 484, 49–54, 2012.
Spratt, R. M. and Lisiecki, L. E.: A Late Pleistocene sea level stack, Clim. Past, 12, 1079–1092, https://doi.org/10.5194/cp-12-1079-2016, 2016.
Staiger, J., Gosse, J., Toracinta, R., Oglesby, B., Fastook, J., and
Johnson, J. V.: Atmospheric scaling of cosmogenic nuclide production:
climate effect, J. Geophys. Res.-Sol. Ea., 112, B02205, https://doi.org/10.1029/2005JB003811, 2007.
Stone, J. O., Allan, G. L., Fifield, L. K., and Cresswell, R. G.: Cosmogenic chlorine-36 from calcium spallation, Geochim. Cosmochim. Ac., 60, 679–692, https://doi.org/10.1016/0016-7037(95)00429-7, 1996.
Tarasov, L., Dyke, A. S., Neal, R. M., and Peltier, W. R.: A data-calibrated
distribution of deglacial chronologies for the North American ice complex
from glaciological modeling, Earth Planet. Sc. Lett., 315–316,
30–40, https://doi.org/10.1016/j.epsl.2011.09.010, 2012.
Taylor, M. A., Hendy, I. L., and Pak, D. K.: Deglacial ocean warming and
marine margin retreat of the Cordilleran Ice Sheet in the North Pacific
Ocean, Earth Planet. Sc. Lett., 403, 89–98, https://doi.org/10.1016/j.epsl.2014.06.026, 2014.
Walczak, M. H., Mix, A. C., Cowan, E. A., Fallon, S., Fifield, L. K., Alder, J. R., Du, J., Haley, B., Hobern, T., and Padman, J.: Phasing of millennial-scale climate variability in the Pacific and Atlantic Oceans, Science, 370, 716–720, 2020.
Warner, B. G., Mathewes, R. W., and Clague, J. J.: Ice-free conditions on
the Queen Charlotte Islands, British Columbia, at the height of late
Wisconsin glaciation, Science, 218, 675–677, 1982.
Wilcox, P. S., Dorale, J. A., Baichtal, J. F., Spotl, C., Fowell, S. J.,
Edwards, R. L., and Kovarik, J. L.: Millennial-scale glacial climate
variability in Southeastern Alaska follows Dansgaard-Oeschger cyclicity, Sci.
Rep., 9, 7880, https://doi.org/10.1038/s41598-019-44231-1, 2019.
Wilson, F. H., Hults, C. P., Mull, C. G., and Karl, S. M.: Geologic map of
Alaska, US Department of the Interior, US Geological Survey, https://doi.org/10.3133/gip168, 2015.
Young, N. E., Schaefer, J. M., Briner, J. P., and Goehring, B. M.: A
10Be production-rate calibration for the Arctic, J. Quaternary Sci., 28, 515–526, 2013.
Short summary
We present a record of ice retreat from the northern Alexander Archipelago, Alaska. During the last ice age (~ 26 000–19 000 years ago), these islands were covered by the Cordilleran Ice Sheet. We tested whether islands were ice-free during the last ice age for human migrants moving from Asia to the Americas. We found that these islands became ice-free between ~ 15 100 years ago and ~ 16 000 years ago, and thus these islands were not suitable for human habitation during the last ice age.
We present a record of ice retreat from the northern Alexander Archipelago, Alaska. During the...
