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Cosmogenic nuclide chronology of pre-last glacial maximum moraines at Lago Buenos Aires, 46�S, Argentina

Published online by Cambridge University Press:  20 January 2017

Michael R. Kaplan ,
Daniel C. Douglass ,
Bradley S. Singer ,
Robert P. Ackert  and
Marc W. Caffee
Michael R. Kaplan*
Affiliation:
Department of Geology and Geophysics, University of Wisconsin-Madison, 1215 West Dayton Street, Madison, WI 53706, USA School of GeoSciences, University of Edinburgh, Edinburgh, EH8 9XP, Scotland, UK
Daniel C. Douglass
Affiliation:
Department of Geology and Geophysics, University of Wisconsin-Madison, 1215 West Dayton Street, Madison, WI 53706, USA
Bradley S. Singer
Affiliation:
Department of Geology and Geophysics, University of Wisconsin-Madison, 1215 West Dayton Street, Madison, WI 53706, USA
Robert P. Ackert
Affiliation:
Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, MA 02138, USA
Marc W. Caffee
Affiliation:
Department of Physics, Purdue University, West Lafayette, IN 47907-1396, USA
*
*Corresponding author. School of GeoSciences, University of Edinburgh, Edinburgh, EH8 9XP, Scotland, UK. Fax: +44 131 650 2524.E-mail address:mkaplan@geo.ed.ac.uk (M.R. Kaplan).
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Abstract

At Lago Buenos Aires, Argentina, 10Be, 26Al, and 40Ar/39Ar ages range from 190,000 to 109,000 yr for two moraines deposited prior to the last glaciation, 23,000�16,000 yr ago. Two approaches, maximum boulder ages assuming no erosion, and the average age of all boulders and an erosion rate of 1.4 mm/103 yr, both yield a common estimate age of 150,000�140,000 yr for the two moraines. The erosion rate estimate derives from 10Be and 26Al concentrations in old erratics, deposited on moraines that are >760,000 yr old on the basis of interbedded 40Ar/39Ar dated lavas. The new cosmogenic ages indicate that a major glaciation during marine oxygen isotope stage 6 occurred in the mid-latitude Andes. The next five youngest moraines correspond to stage 2. There is no preserved record of a glacial advance during stage 4. The distribution of dated boulders and their ages suggest that at least one major glaciation occurred between 760,000 and >200,000 yr ago. The mid-latitude Patagonian glacial record, which is well preserved because of low erosion rates, indicates that during the last two glacial cycles major glaciations in the southern Andes have been in phase with growth and decay of Northern Hemisphere ice sheets, especially at the 100,000 yr periodicity. Thus, glacial maxima are global in nature and are ultimately paced by small changes in Northern Hemisphere insolation.

Keywords

Exposure ageCosmogenic nuclideSouth AmericaGlacial geologyPaleoclimatologyGlaciationSouthern HemisphereMilankovitchQuaternary periodStage 6
Type
Research Article
Information
Quaternary Research , Volume 63 , Issue 3 , May 2005 , pp. 301 - 315
Copyright
University of Washington

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References

Ackert, R.P., Singer, B.S., Guillou, H., Kaplan, M.R., Kurz, M.D., (2003). Long-term cosmogenic 3He production rates from 40Ar/39Ar and K�Ar dated Patagonian lava flows at 47�S. Earth and Planetary Science Letters 210, 119–136.CrossRefGoogle Scholar
Basile, I., Grousset, F.E., Revel, M., Petit, J.R., Biscaye, P.E., Barkov, N.I., (1997). Patagonian origin of glacial dust deposited in East Antarctica (Vostok and Dome C) during glacial stages 2, 4, and 6. Earth and Planetary Science Letters 146, 573–589.Google Scholar
Becquey, S., Gersonde, R.A., (2003). 0.55-Ma paleotemperature record from the Subantarctic zone: implications for Antarctic circumpolar current development. Paleoceanography 18, .CrossRefGoogle Scholar
Berger, A., Loutre, M.F., (1991). Insolation values for the climate of the last 10 million years. Quaternary Science Reviews 10, 297–318.Google Scholar
Bierman, P.R., Caffee, M.W., Davis, P.T., Marsella, K., Pavich, M., Colgan, P., Mickelson, D., (2002). Rates and timing of earth surface processes from in situ-produced cosmogenic Be-10. Grew, E.S., Beryllium: Mineralogy, Petrology, and Geochemistry. Series: Reviews in Mineralogy and Geochemistry vol. 50, Mineralogical Society of America, Washington, DC., 147–205.Google Scholar
Broecker, W.S., Denton, G.H., (1989). The role of ocean�atmosphere reorganizations in glacial cycles. Geochimica et Cosmochimica Acta 53, 2465–2501.CrossRefGoogle Scholar
Brook, E.J., Kurz, M.D., Ackert, R.P. Jr., Denton, G.H., Brown, E.T., Raisbeck, G.M., Yiou, F., (1993). Chronology of Taylor Glacier advances in Arena Valley, Antarctica, using in situ cosmogenic 3He and 10Be. Quaternary Research 39, 11–23.CrossRefGoogle Scholar
Brown, E.T., Brook, E.J., Raisbeck, G.M., Yiou, F., Kurz, M.D., (1992). Effective attenuation of cosmic rays producing 10Be and 26Al in quartz: implications for exposure dating. Geophysical Research Letters 19, 369–372.CrossRefGoogle Scholar
Caldenius, C.G., (1932). Las glaciaciones Cuaternarias en la Patagonia and Tierra del Fuego. Geografiska Annaler 14, 1–164.Google Scholar
Clapperton, C.M., (1993). Quaternary Geology and Geomorphology of South America. Elsevier, .Google Scholar
Denton, G.H., Hughes, T.J., Karl�n, W., (1986). Global ice-sheet system interlocked by sea level. Quaternary Research 26, 3–26.Google Scholar
Gillespie, A.R., Bierman, P.R., (1995). Precision of terrestrial exposure ages and erosion rates from analysis of cosmogenic isotopes produced in situ. Journal of Geophysical Research 100, 24637–24649.Google Scholar
Gosse, J.C., Phillips, F.M., (2001). Terrestrial in situ cosmogenic nuclides: theory and application. Quaternary Science Reviews 20, 1475–1560.CrossRefGoogle Scholar
J.C., Gosse, J.O., Stone, (2001). Terrestrial cosmogenic nuclide methods passing milestones toward paleo-altimetry. EOS 82, 82, 86, 89.Google Scholar
Granger, D.E., Riebe, C.S., Kirchner, J.W., Finkel, R.C., (2001). Modulation of erosion on steep granitic slopes by boulder armoring, as revealed by cosmogenic 26Al and 10Be. Earth and Planetary Science Letters 186, 269–281.Google Scholar
Hallet, B., Putkonen, J.K., (1994). Surface dating of dynamic landforms. Young boulders on aging moraines. Science 265, 937–940.Google Scholar
Hays, J.D., Imbrie, J., Shackleton, N.J., (1976). Variations in the earth's orbit: pacemaker of the ice ages. Science 194, 1121–1131.Google Scholar
Imbrie, J., Berger, A., Boyle, E.A., Clemens, S.C., Duffy, A., Howard, W.R., Kukla, G., Kutzbach, J., Martinson, D.G., McIntyre, A., Mix, A.C., Molfino, B., Morley, J.J., Peterson, L.C., Pisias, N.G., Prell, W.L., Raymo, M.E., Shackleton, N.J., Toggweiler, J.R., (1993). On the structure and origin of major glaciation cycles 2. The 100,000-year cycle. Paleoceanography 8, 699–735.CrossRefGoogle Scholar
Kaplan, M.R., Ackert, R.P., Singer, B.S., Douglass, D.C., Kurz, M.D., (2004). Cosmogenic nuclide chronology of millennial-scale glacial advances during O-isotope Stage 2 in Patagonia. Geological Society of America Bulletin 116, 308–321.Google Scholar
Lal, D., (1991). Cosmic ray labeling of erosion surfaces: in-situ nuclide production rates and erosion models. Earth and Planetary Science Letters 104, 424–439.Google Scholar
Licciardi, J.M., Kurz, M.D., Clark, P.U., Brook, E.J., (1999). Calibration of cosmogenic 3He production rates from Holocene lava flows in Oregon, USA, and effects of the Earth's magnetic field. Earth and Planetary Science Letters 172, 261–271.CrossRefGoogle Scholar
Masarik, J., Frank, M., Sch�fer, J.M., Wieler, R., (2001). Correction of in situ cosmogenic nuclide production rates for geomagnetic field intensity variations during the past 800,000 years. Geochimica et Cosmochimica Acta 65, 2995–3003.CrossRefGoogle Scholar
Mercer, J.H., (1983). Cenozoic glaciation in the southern hemisphere. Annual Reviews of Earth and Planetary Science 11, 99–132.CrossRefGoogle Scholar
Middleton, R., Brown, L., Dezfouly-Arjomandy, B., Klein, J., (1993). On 10Be standards and the half life of 10Be. Nuclear instruments and methods in physics research B82, 399–403.CrossRefGoogle Scholar
M�rner, N.-A., Sylwan, C., (1989). Magnetostratigraphy of the Patagonian moraine sequence at Lago Buenos Aires. Journal of South American Earth Sciences 2, 385–389.CrossRefGoogle Scholar
Nishiizumi, K., Winterer, E.L., Kohl, C.P., Klein, J., Middleton, R., Lal, D., Arnold, J.R., (1989). Cosmic ray production rates of 10Be and 26Al in quartz from glacially polished rocks. Journal of Geophysical Research 94, 17907–17915.CrossRefGoogle Scholar
Partridge, T.C., Granger, D.E., Caffee, M.W., Clarke, R.J., (2003). Lower Pliocene hominid remains from Sterkfontein. Science 300, 607–612.CrossRefGoogle ScholarPubMed
Petit, J.R., Jouzel, J., Raynaud, D., Barkov, N.I., Barnola, J.M., Basile, I., Bender, M., Chappellaz, J., Davis, M., Delaygue, G., Delmotte, M., Kotlyakov, V.M., Legrand, M., Lipenkov, V.Y., Lorius, C., P�pin, L., Ritz, C., Saltzman, E., Stievenard, M., (1998). Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399, 429–436.CrossRefGoogle Scholar
Phillips, F.M., Zreda, M.G., Gosse, J.C., Klein, J., Evenson, E.B., Hall, R.D., Chadwick, O.A., Sharma, P., (1997). Cosmogenic 36Cl and 10Be ages of Quaternary glacial and fluvial deposits of the Wind River Range, Wyoming. Geological Society of America Bulletin 109, 453–1463.Google Scholar
Putkonen, J., Swanson, T., (2003). Accuracy of cosmogenic ages for moraines. Quaternary Research 59, 255–261.CrossRefGoogle Scholar
Shackleton, N.J., Berger, A., Peltier, W.R., (1990). An alternative astronomical calibration of the lower Pleistocene timescale based on ODP site 677. Transactions of the Royal Society of Edinburgh. Earth Sciences 81, 251–261.Google Scholar
Shanahan, T.M., Zreda, M., (2000). Chronology of Quaternary glaciations on Mount Kenya and Kilimanjaro. Earth and Planetary Science Letters 177, 23–42.Google Scholar
Sharma, P., Middleton, R., (1989). Radiogenic production of 10Be and 26Al in uranium and thorium ores: implications for studying terrestrial samples containing low levels of 10Be and 26Al. Geochimica et Cosmochimica Acta 53, 709–716.Google Scholar
Singer, B.S., Thompson, R.A., Dungan, M.A., Feeley, T.C., Nelson, S.T., Pickens, J.C., Brown, L.L., Wulff, A.W., Davidson, J.P., Metzger, J., (1997). Volcanism and erosion during the past 930 thousand years at the Tatara�San Pedro complex, Chilean Andes. Geological Society of America Bulletin 109, 127–142.Google Scholar
Singer, B.S., Ackert, R.P., Guillou, H., (2004). 40Ar/39Ar and K�Ar chronology of Pleistocene glaciations in Patagonia. Geological Society of America Bulletin 116, 434–450.CrossRefGoogle Scholar
Small, E.E., Anderson, R.S., Repka, J.R., Finkel, R., (1997). Erosion rates of alpine bedrock summit surfaces deduced from in situ 10Be and 26Al. Earth and Planetary Science Letters 150, 413–425.Google Scholar
Stone, J.O., (2000). Air pressure and cosmogenic isotope production. Journal of Geophysical Research 105, 23753–23759.CrossRefGoogle Scholar
Sugden, D.E., Hulton, N.R.J., Purves, R.S., (2002). Modelling the inception of the Patagonian icesheet. Quaternary International 95/96, 55–64.Google Scholar
Taylor, J.R., (1982). An Introduction to Error Analysis. University Science Books, Mill Valley, California.Google Scholar
Zreda, M.G., Phillips, F.M., (1995). Insights into alpine moraine development from cosmogenic 36Cl buildup dating. Geomorphology 14, 149–156.CrossRefGoogle Scholar