Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-27T07:25:39.441Z Has data issue: false hasContentIssue false
  • English
  • Français

Accuracy of cosmogenic ages for moraines☆

Published online by Cambridge University Press:  20 January 2017

Jaakko Putkonen  and
Terry Swanson
Jaakko Putkonen
Affiliation:
Quaternary Research Center and Department of Earth and Space Sciences, University of Washington, MS 351310, Seattle, WA 98195, USA
Terry Swanson
Affiliation:
Quaternary Research Center and Department of Earth and Space Sciences, University of Washington, MS 351310, Seattle, WA 98195, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Analyses of all published cosmogenic exposure ages for moraine boulders show an average age range of 38% between the oldest and youngest boulders from each moraine. This range conflicts with the common assumption that ages of surface boulders are the same as the age of the landform. The wide spread in boulder ages is caused by erosion of the moraine surface and consequent exhumation of fresh boulders. A diffusion model of surface degradation explains the age range and shows that a randomly sampled small set of boulders (n = 3–7) will always yield a lower age limit for the moraine. The model indicates that for identical dating accuracy, six to seven boulders are needed from old and tall moraines (40,000–100,000 yr, 50–100 m initial height) but only one to four boulders from small moraines (20,000–100,000 yr, 10–20 m). By following these guidelines the oldest obtained boulder age will be ≥90% of the moraine age (95% probability). This result is only weakly sensitive to a broad range of soil erosion rates. Our analysis of published boulder ages indicates that <3% of all moraine boulders have prior exposure, and 85% of these boulders predate the dated moraine.

Keywords

Cosmogenic exposure-age datingMoraineBoulderDatingErosion
Type
Articles
Information
Quaternary Research , Volume 59 , Issue 2 , March 2003 , pp. 255 - 261
Copyright
Elsevier Science (USA)

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

☆

Supplementary data for this article (Appendix) are available on Science Direct (http://www.sciencedirect.com).

References

Andrews, D.J., Bucknam, R.C., (1987). Fitting degradation of shoreline scarps by a non-linear diffusion model. Journal of Geophysical Research 92 Google Scholar
Andrews, D.J., and Hanks, T.C. Scarp degraded by linear diffusion. inverse solution for age. Journal of Geophysical Research 90, (1985). 10193 10208.Google Scholar
Barrows, T.T., Stone, J.O., Fifield, L.K., and Cresswell, R.G. The timing of the last Glacial Maximum in Australia. Quaternary Science Reviews 21, (2002). 159 173.Google Scholar
Briner, J.P., Swanson, T.W., and Caffee, M. Late Pleistocene cosmogenic 36Cl glacial chronology of the southwestern Ahklun Mountains, Alaska. Quaternary Research 56, (2001). 148 154.CrossRefGoogle Scholar
Brook, E.J., Kurz, M.D., Ackert, J.R.P., Denton, G.H., Brown, E.T., Raisbeck, G.M., and Yiou, F. Chronology of Taylor Glacier advances in Arena Valley, Antarctica, using in situ cosmogenic 3He and 10Be. Quaternary Research 39, (1993). 11 23.Google Scholar
Brook, E.J., Kurz, M.D., Ackert, J.R.P., Raisbeck, G.M., and Yiou, F. Cosmogenic nuclide exposure ages and glacial history of Late Quaternary Ross Sea Drift in McMurdo Sound, Antarctica. Earth and Planetary Science Letters 131, (1995). 41 56.Google Scholar
Burke, R.M., and Birkeland, P.W. Reevaluation of multiparameter relative dating techniques and their application to the glacial sequence along the eastern escarpment of the Sierra Nevada, California. Quaternary Research 11, (1979). 21 51.CrossRefGoogle Scholar
Bursik, M. Relative dating of moraines based on landform degradation, Lee Vining Canyon, California. Quaternary Research 35, (1991). 451 455.Google Scholar
Colman, S.M., and Pierce, K.L. Glacial sequence Near McCall, Idaho. weathering rinds, soil development, morphology and other relative age criteria. Quaternary Research 25, (1986). 25 42.CrossRefGoogle Scholar
Davis, P.T., Bierman, P.R., Marsella, K.A., Caffee, M.W., and Southon, J.R. Cosmogenic analysis of glacial terrains in the eastern Canadian Arctic. a test for inherited nuclides and the effectiveness of glacial erosion. Annals of Glaciology 28, (1999). 181 188.Google Scholar
Duk-Rodkin, A., Barendregt, R.W., Tarnocai, C., and Phillips, F.M. Late Tertiary to Late Quaternary record in the MacKenzie Mountains, Northwest Territories, Canada. stratigraphy, paleosols, paleomagnetism, and Chlorine-36. Canadian Journal of Earth Sciences 33, (1995). 875 895.Google Scholar
Dunne, T., and Leopold, L.B. Water in Environmental Planning. (1995). W.H. Freeman and Company, New York.Google Scholar
Gillespie, A.R., Bierman, P.R., (1995). Precision of terrestrial exposure ages and erosion rates estimated from analysis of cosmogenic isotopes produced in situ. Journal of Geophysical Research 100 B12, 24,637–24,649.Google Scholar
Gosse, J.C., Evenson, E.B., Klein, J., Lawn, B., and Middleton, R. Precise cosmogenic 10Be measurements in Western North America. support for global Younger Dryas cooling event. Geology 23, (1995). 877 880.2.3.CO;2>CrossRefGoogle Scholar
Gosse, J.C., Klein, J., Evenson, E.B., Lawn, B., and Middleton, R. Beryllium-10 dating of the duration and retreat of the last Pinedale glacial sequence. Science 268, (1995). 1329 1333.CrossRefGoogle ScholarPubMed
Gosse, J.C., and Phillips, F.M. Terrestrial in situ cosmogenic nuclides. theory and application. Quaternary Science Reviews 20, (2001). 1475 1560.CrossRefGoogle Scholar
Gualtieri, L., Glushkova, O., and Brigham-Grette, J. Evidence for restricted ice extent during the last glacial maximum in the Koryak Mountains of Chukotka, far eastern Russia. GSA Bulletin 112, (2000). 1106 1118.Google Scholar
Hallet, B., and Putkonen, J.K. Surface dating of dynamic landforms. young boulders on aging moraines. Science 265, (1994). 937 940.CrossRefGoogle ScholarPubMed
Hanks, T.C., and Andrews, D.J. Effect of far-field slope on morphological dating of scraplike landforms. Journal of Geophysical Research 94, (1989). 565 573.Google Scholar
Hanks, T.C., Bucknam, R.C., Lajoie, K.R., and Wallace, R.E. Modification of wave-cut and faulting-controlled landforms. Journal of Geophysical Research 89, (1984). 5771 CrossRefGoogle Scholar
Ivy-Ochs, S., Schluchter, C., Kubik, P., and Denton, G.H. Moraine exposure dates imply synchronous Younger Dryas glacier advances in the European Alps and in the Southern Alps of New Zealand. Geografiska Annaler 81, (1999). 313 323.Google Scholar
Lederer, C.M., and Shirely, V.S. Table of Isotopes. (1978). Wiley, New York.Google Scholar
Licciardi, J.M., Clark, P.U., Brook, E.J., Pierce, K.L., Kurz, M.D., Elmore, D., and Sharma, P. Cosmogenic 3He and 10Be chronologies of the late Pinedale northern Yellowstone ice cap, Montana, USA. Geology 29, (2001). 1095 1098.Google Scholar
Marsella, K.A., Bierman, P.R., Davis, P.T., and Caffee, M.W. Cosmogenic 10Be and 26Al ages for the Last Glacial Maximum, eastern Baffin Island, Arctic Canada. GSA Bulletin 112, (2000). 1296 1312.Google Scholar
Nash, D.B. Forms of bluffs degraded for different lengths of time in Emmet County, Michigan, USA. Earth Surface Processes 5, (1980). 331 345.Google Scholar
Nash, D.B. Morphologic dating of degraded normal fault scarps. Journal of Geology 88, (1980). 353 360.Google Scholar
Nishiizumi, K., Winterer, E.L., Kohl, C.P., Klein, J., Middleton, R., Lal, D., and Arnold, J.R. Cosmic ray production rates of 10Be and 26Al in Quartz from glacially polished rocks. Journal of Geophysical Research 94, (1989). 17907 17915.Google Scholar
Owen, L.A., Finkel, R.C., Caffee, M.W., and Gualtieri, L. Timing of multiple late Quaternary glaciations in the Hunza Valley, Karakoram Mountains, northern Pakistan. defined by cosmogenic radionuclide dating of moraines. GSA Bulletin 114, (2002). 593 604.2.0.CO;2>CrossRefGoogle Scholar
Owen, L.A., Gualtieri, L., Finkel, R.C., Caffee, M.W., Benn, D.I., and Sharma, M.C. Cosmogenic radionuclide dating of glacial landforms in the Lahul Himalaya, northern India. defining the timing of late Quaternary glaciation. Journal of Quaternary Science 16, (2001). 555 563.CrossRefGoogle Scholar
Phillips, F.M., Zreda, M., Shanahan, T.M., Bursik, M.I., and Plummer, M.A. (2000). Cosmogenic depth profiles and erosion modeling: new results from Bloody Canyon moraines, Mono Basin, California, in: American Geophysical Union Fall Meeting, AGU, San Francisco, USAGoogle Scholar
Phillips, F.M., Zreda, M.G., Benson, L.V., Plummer, M.A., Elmore, D., and Sharma, P. Chronology for fluctuations in Late Pleistocene Sierra Nevada glaciers and lakes. Science 274, (1996). 749 751.CrossRefGoogle Scholar
Phillips, F.M., Zreda, M.G., Gosse, J.C., Klein, J., Evenson, E.B., Hall, R.D., Chadwick, O.A., and Sharma, P. Cosmogenic 36Cl and 10Be ages of Quaternary glacial and fluvial deposits of the Wind River Range, Wyoming. GSA Bulletin 109, (1997). 1453 1463.Google Scholar
Phillips, F.M., Zreda, M.G., Smith, S.S., Elmore, D., Kubik, P.W., and Sharma, P. Cosmogenic Chlorine-36 Chronology for glacial deposits at Bloody Canyon, eastern Sierra Nevada. Science 248, (1990). 1529 1532.CrossRefGoogle ScholarPubMed
Pierce, K.L., and Colman, S.M. Effect of height and orientation (Microclimate) on geomorphic degradation rates and processes, Late-Glacial terrace scarps in Central Idaho. Geological Society of America Bulletin 97, (1986). 869 2.0.CO;2>CrossRefGoogle Scholar
Selby, M.J., (1990). Hillslope Material & Processes. Oxford University Press, Google Scholar
Shanahan, T.M., and Zreda, M. Chronology of Quaternary glaciations in East Africa. Earth and Planetary Science Letters 177, (2000). 23 42.Google Scholar
Sharp, R.P., and Birman, J.H. Additions to classical sequence of Pleistocene glaciations, Sierra Nevada, California. Geological Society of America Bulletin 74, (1963). 1079 1086.CrossRefGoogle Scholar
Steig, E.J., Wolfe, A.P., and Miller, G.H. Wisconsinan refugia and the glacial history of eastern Baffin Island, Arctic Canada. coupled evidence from cosmogenic isotopes and lake sediments. Geology 26, (1998). 835 838.2.3.CO;2>CrossRefGoogle Scholar
Swanson, T.W., and Porter, S.C. (2000). 36Cl evidence for maximum late Pleistocene glacier extent in the Cascade Range during Marine Isotope Substage 5d, in: Geological Society of America Abstracts with Programs, Geological Society of America, Reno, Nevada, pp. A-511Google Scholar
Zreda, M.G., and Phillips, F.M. Insights in the alpine moraine development from cosmogenic 36Cl buildup dating. Geomorphology 14, (1995). 149 156.CrossRefGoogle Scholar
Zreda, M.G., Phillips, F.M., and Elmore, D. Cosmogenic 36Cl accumulation in unstable landforms, 2, Simulations and observations on eroding moraines. Water Resources Research 30, (1994). 3127 3136.CrossRefGoogle Scholar
Supplementary material: File

Putkonen and Swanson Supplementary Material

Appendices

Download Putkonen and Swanson Supplementary Material(File)
File 61.4 KB