Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-28T02:48:39.394Z Has data issue: false hasContentIssue false

Cosmogenic nuclide exposure ages for moraines in the Lago San Martin Valley, Argentina

Published online by Cambridge University Press:  20 January 2017

Neil F. Glasser*
Affiliation:
Centre for Glaciology, Institute of Geography and Earth Sciences, Aberystwyth University, Ceredigion SY23 3DB, Wales, UK
Krister N. Jansson
Affiliation:
Department of Physical Geography and Quaternary Geology, University of Stockholm, SE-106 91, Stockholm, Sweden
Bradley W. Goodfellow
Affiliation:
Geological and Environmental Sciences, 450 Serra Mall, Stanford University, Stanford, CA 94305, USA
Hernan de Angelis
Affiliation:
Department of Physical Geography and Quaternary Geology, University of Stockholm, SE-106 91, Stockholm, Sweden
Helena Rodnight
Affiliation:
Institute for Geology and Palaeontology, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria
Dylan H. Rood
Affiliation:
Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, L-397 Livermore, CA 94550, USA
*
Corresponding author.

Abstract

At several times during the Quaternary, a major eastward-flowing outlet glacier of the former Patagonian Ice Sheet occupied the Lago San Martin Valley in Argentina (49°S, 72°W). We present a glacial chronology for the valley based on geomorphological mapping and cosmogenic nuclide (10Be) exposure ages (n = 10) of boulders on moraines and lake shorelines. There are five prominent moraine belts in the Lago San Martin Valley, associated with extensive sandar (glaciofluvial outwash plains) and former lake shorelines. Cosmogenic nuclide exposure ages for boulders on these moraines indicate that they formed at 14.3 ± 1.7 ka, 22.4 ± 2.3 ka, 34.4 ± 3.4 ka to 37.6 ± 3.4 ka (and possibly 60 ± 3.5 ka), and 99 ± 11 ka (1σ). These dated glacier advances differ from published chronologies from the Lago San Martin Valley based on 14C age determinations from organic sediments and molluscs in meltwater channels directly in front of moraines or in kettleholes within end moraine ridges. The moraine boulder ages also point to possible pre-LGM glacial advances during the last glacial cycle and a key observation from our data is that the LGM glaciers were probably less extensive in the Lago San Martin Valley than previously thought.

Type
Research Article
Copyright
University of Washington

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.)

References

Ackert, R.P. Jr., Singer, B.S., Kurz, M.D., Guillou, H., and Kaplan, M.R. Calibration of 3He production rates against 40Ar/39Ar and K-Ar dated Patagonia lava flows, 46°S. Earth and Planetary Science Letters 210, (2003). 119136.Google Scholar
Ackert, R.P., Becker, R.A., Singer, B.S., Kurz, M.D., Caffee, M.W., and Mickelson, D.M. Patagonian glacier response during the Late Glacial–Holocene transition. Science 321, (2008). 392395.CrossRefGoogle ScholarPubMed
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. Quaternary Geochronology 3, (2008). 174195.Google Scholar
Bentley, M.J., Sugden, D.E., Hulton, N.R.J., and McCulloch, R.D. The landforms and pattern of deglaciation in the Strait of Magellan and Bahía Inútil, southernmost South America. Geografiska Annaler 87A, (2005). 313333.Google Scholar
Berger, A., and Loutre, M.F. Insolation values for the climate of the last 10 million years. Quaternary Science Reviews 10, (1991). 297317.Google Scholar
Caldenius, C.C. Las glaciaciones cuaternarios en la Patagonia y Tierra del Fuego. Geografiska Annaler 14, (1932). 1164. (English summary, 144-157) Google Scholar
Denton, G., Lowell, T., Heusser, C., Schlüchter, C., Andersen, B., Heusser, L., Moreno, P., and Marchant, D.R. Geomorphology, stratigraphy and radiocarbon chronology of Llanquihue drift in the area of the Southern Lake District, Seno Reloncaví and Isla de Chiloé, Chile. Geografiska Annaler 81A, (1999). 167229.Google Scholar
Denton, G.H., Heusser, C.J., Lowell, T.V., Moreno, P.I., Andersen, B.G., Heusser, L.E., Schlüchter, C., and Marchant, D.R. Interhemispheric linkage of paleoclimate during the last glaciation. Geografiska Annaler 81A, (1999). 107153.Google Scholar
Douglass, D.C., Singer, B.S., Kaplan, M.R., Mickleson, D.M., and Caffee, M.W. Cosmogenic nuclide surface exposure dating of boulders on last-glacial and late-glacial moraines, Lago Buenos Aires, Argentina: interpretative strategies and paleoclimate implications. Quaternary Geochronology 1, (2006). 4358.CrossRefGoogle Scholar
Fabel, D., Small, D., Miguens-Rodriguez, M., and Freemnan, S.P.H.T. Cosmogenic nuclide exposure ages from the ‘Parallel Roads’ of Glen Roy, Scotland. Journal of Quaternary Science 25, (2009). 597603.Google Scholar
Fogwill, C.J., and Kubik, P.W. A glacial stage spanning the Antarctic Cold Reversal in Torres del Paine (51°S), Chile, based on preliminary cosmogenic exposure ages. Geografiska Annaler 87A, (2005). 403408.Google Scholar
Glasser, N.F., and Jansson, K. The glacial map of southern South America. Journal of Maps v2008, (2008). 175196.Google Scholar
Glasser, N.F., Harrison, S., Winchester, V., and Aniya, M. Late Pleistocene and Holocene palaeoclimate and glacier fluctuations in Patagonia. Global and Planetary Change 43, (2004). 79101.Google Scholar
Glasser, N.F., Jansson, K.N., Harrison, S., and Kleman, J. The glacial geomorphology and Pleistocene history of South America between 38°S and 56°S. Quaternary Science Reviews 27, (2008). 365390.Google Scholar
Gosse, J.C., and Phillips, F.M. Terrestrial in situ cosmogenic nuclides: theory and application. Quaternary Science Reviews 20, (2001). 14751560.Google Scholar
Harrison, S. The Pleistocene glaciations of Chile. Ehlers, J., and Gibbard, P.L. Pleistocene Glaciations: Extent and Chronology, INQUA Working Group 5. (2004). Elsevier, Amsterdam. 89103.Google Scholar
Hein, A.S., Hulton, N.R.J., Dunai, T.J., Schnabel, C., Kaplan, M.R., Naylor, M., and Xu, S. Middle Pleistocene glaciation in Patagonia dated by cosmogenic-nuclide measurements on outwash gravels. Earth and Planetary Science Letters 286, (2009). 184197.Google Scholar
Heisinger, B., Lal, D., Jull, A.J.T., Kubik, P., Ivy-Ochs, S., Knie, K., and Nolte, E. Production of selected cosmogenic radionuclides by muons: 2. Capture of negative muons. Earth and Planetary Science Letters 200, (2002). 357369.Google Scholar
Heisinger, B., Lal, D., Jull, A.J.T., Kubik, P., Ivy-Ochs, S., Neumaier, S., Knie, K., Lazarev, V., and Nolte, E. Production of selected cosmogenic radionuclides by muons 1. Fast muons. Earth and Planetary Science Letters 200, (2002). 345355.Google Scholar
Hulton, N.R.J., Sugden, D.E., Payne, A.J., and Clapperton, C.M. Glacier modelling and the climate of Patagonia during the last glacial maximum. Quaternary Research 42, (1994). 119.Google Scholar
Hulton, N.R.J., Purves, R.S., McCulloch, R.D., Sugden, D.E., and Bentley, M.J. The Last Glacial Maximum and deglaciation in southern South America. Quaternary Science Reviews 21, (2002). 233241.Google Scholar
Kaiser, J., Lamy, F., Arz, H.W., and Hebbeln, D. Dynamics of the millennial-scale sea surface temperature and Patagonian Ice Sheet fluctuations in southern Chile during the last 70 kyr (ODP Site 1233). Quaternary International 161, (2007). 7789.CrossRefGoogle Scholar
Kaplan, M.R., Ackert, R.P., Singer, B.S., Douglass, D.C., and Kurz, M.D. Cosmogenic nuclide chronology of millenial-scale glacial advances during O-isotope Stage 2 in Patagonia. Bulletin of the Geological Society of America 116, (2004). 308321.Google Scholar
Kaplan, M.R., Douglass, D.C., Singer, B.S., Ackert, R.P., and Caffee, M.W. Cosmogenic nuclide chronology of pre-last glacial maximum moraines at Lago Buenos Aires, 46°S, Argentina. Quaternary Research 63, (2005). 301315.Google Scholar
Kaplan, M.R., Fogwill, C.J., Sugden, D.E., Hulton, N., Kubik, P.W., and Freeman, S.P.H.T. Southern Patagonian glacial chronology for the Last Glacial period and implications for Southern Ocean climate. Quaternary Science Reviews 27, (2008). 284294.Google Scholar
Kaplan, M.R., Moreno, P.I., and Rojas, M. Glacial dynamics in southernmost South America during Marine Isotope Stage 5e to the Younger Dryas chron: a brief review with a focus on cosmogenic nuclide measurements. Journal of Quaternary Science 23, (2008). 649658.CrossRefGoogle Scholar
Kohl, C.P., and Nishiizumi, K. Chemical isolation of quartz for measurement of in situ-produced cosmogenic nuclides. Geochimica et Cosmochimica Acta 56, (1992). 35833587.CrossRefGoogle Scholar
Lal, D. Cosmic ray labeling of erosion surfaces: in situ nuclide production rates and erosion models. Earth and Planetary Science Letters 104, (1991). 424439.CrossRefGoogle Scholar
Lambert, F. et al. Dust-climate couplings over the past 800,000 years from the EPICA Dome C ice core. Nature 425, (2008). 616619.Google Scholar
Lamy, F., Kaiser, J., Ninnemann, U., Hebbeln, D., Arz, H.W., and Stoner, J. Antarctic timing of surface water changes off Chile and Patagonian ice sheet response. Science 304, (2004). 19591962.Google Scholar
Marden, C.J., and Clapperton, C.M. Fluctuations of the Southern Patagonian Icefield during the last glaciation and the Holocene. Journal of Quaternary Science 10, (1995). 197209.Google Scholar
McCulloch, R., Fogwill, C., Sudgen, D., Bentley, M., and Kubik, P. Chronology of the Last Glaciation in Central Strait of Magellan and Bahía Inútil, Southernmost South America. Geografiska Annaler 87A, 2 (2005). 289312.Google Scholar
Mercer, J.H Glacial history of southernmost South America. Quarternary Research 6, (1976). 125166.Google Scholar
Moreno, P.I., Francois, J.P., Villa-Martinez, R.P., and Moy, C.M. Millennial-scale variability in Southern Hemisphere westerly wind activity over the last 5000 years in SW Patagonia. Quaternary Science Reviews 28, (2009). 2538.Google Scholar
Nishiizumi, K., Imamura, M., Caffee, M.W., and Southon, J.R. Absolute calibration of 10Be AMS standards. Nuclear Instruments and Methods in Physics Research B 258, (2007). 403413.Google Scholar
Petit, J.R. et al. Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399, (1999). 429436.Google Scholar
Putkonen, J., and Swanson, T. Accuracy of cosmogenic ages for moraines. Quaternary Research 59, (2003). 255261.Google Scholar
Rojas, M. et al. The Southern Westerlies during the last glacial maximum in PMIP2 simulations. Climate Dynamics 32, (2009). 525548.Google Scholar
Singer, B.S., Ackert, R.P., and Guillou, H. 40Ar/39AR and K-Ar chronology of Pleistocene glaciations in Patagonia. Geological Society of America Bulletin 116, (2004). 434450.CrossRefGoogle Scholar
Staiger, J., Gosse, J., Toracinta, R., Oglesby, B., Fastook, J., and Johnson, J.V. Atmospheric scaling of cosmogenic nuclide production: climate effect. Journal of Geophysical Research, Solid Earth 112, (2007). B02205 Google Scholar
Stone, J.O. Air pressure and cosmogenic isotope production. Journal of Geophysical Research 105, B10 (2000). 2375323759.Google Scholar
Strelin, J.A., and Malagnino, E.C. Late-Glacial history of Lago Argentino, Argentina, and age of the Puerto Bandera Moraines. Quaternary Research 54, (2000). 339347.Google Scholar
Sugden, D.E., Bentley, M.J., Fogwill, C.J., Hulton, N.R.J., McCulloch, R.D., and Purves, R.S. Late-Glacial glacier events southernmost South America: a blend of “northern” and “southern” hemispheric climatic signals?. Geografiska Annaler 87A, (2005). 273288.Google Scholar
Sugden, D.E., McCulloch, R.D., Bory, A.J.M., and Hein, A.S. Influence of Patagonian glaciers on Antarctic dust deposition during the last glacial period. Nature Geoscience 2, (2009). 281285.Google Scholar
Turner, K.J., Fogwill, C.J., McCulloch, R.D., and Sugden, D.E. Deglaciation of the eastern flank of the North Patagonian Icefield and associated continental-scale lake diversions. Geografiska Annaler 87A, (2005). 363374.Google Scholar
von Blanckenburg, F., Belshaw, N.S., and O'Nions, R.K. Separation of 9Be and cosmogenic 10Be from environmental materials and SIMS isotope dilution analysis. Chemical Geology 129, (1996). 9399.Google Scholar
Wenzens, G. Fluctuations of outlet and valley glaciers in the Southern Andes (Argentina) during the past 13,000 years. Quaternary Research 51, (1999). 238247.Google Scholar
Wenzens, G. Comment on: “The Last Glacial Maximum and deglaciation in southern South America”. Quaternary Science Reviews 22, (2003). 751754.Google Scholar
Wenzens, G. Glacier advances east of the Southern Andes between the Last Glacial Maximum and 5,000 BP compared with lake terraces of the endorrheic Lago Cardiel (49° S, Patagonia, Argentina). Zeitschrift für Geomorphologie 49, (2005). 433454.Google Scholar
Zech, R., May, J.-H., Kull, C., Ilgner, J., Kubik, P., and Veit, H. Timing of the late Quaternary glaciation in the Andes from 15 to 40°S. Journal of Quaternary Science 23, (2008). 635647.Google Scholar
Zech, R., Zech, J., Kull, C., Kubik, P., and Veit, H. Early last glacial maximum in the southern Central Andes reveals northward shift of the westerlies at 39 ka. Climate of the Past Discussions 6, (2010). 19912004. http://dx.doi.org/10.5194/cpd-6-1991-2010Google Scholar