North-Central Section - 43rd Annual Meeting (2-3 April 2009)

Paper No. 8
Presentation Time: 8:00 AM-12:00 PM

TRACE ELEMENTAL ANALYSIS OF A NORTH AUSTRALIAN STALAGMITE


MICHAELSON, Abigail G., Geology, Cornell College, 600 1st Street West, Mount Vernon, IA 52314, DENNISTON, Rhawn, Geology, Cornell College, 600 1st St West, Mt Vernon, IA 52314, ASMEROM, Yemane, Earth & Planetary Sciences, University of New Mexico, Albuquerque, NM 87131 and POLYAK, Victor J., Earth & Planetary Sciences, University of New Mexico, 200 Yale Blvd., Northrop Hall, Albuquerque, NM 87131, AMichaelson09@CornellCollege.edu

A 152 cm tall stalagmite (KIM1) was collected from the ENSO-sensitive and monsoon-dominated Kimberly region of northwestern Australia. In association with a stable isotope study of KIM1, we conducted 173 trace elemental analyses at 1 cm intervals, corresponding to ~20 year resolution. Mg/Ca and Sr/Ca ratios were covariant both with each other and with carbon isotopic ratios for most of the growth interval (~8800-4050 yr BP), and like the carbon isotope record, were roughly antiphased with oxygen isotopic ratios. One exception is the period 5500-5000 yr BP during which time the Mg/Ca and Sr/Ca ratios deviated from the carbon isotopic ratios and appear instead to correspond with oxygen isotopic ratios. A lag between peaks in reconstructed ENSO activity and Mg/Ca and Sr/Ca ratios is also apparent.