Northeastern Section - 53rd Annual Meeting - 2018

Paper No. 58-5
Presentation Time: 8:00 AM-12:00 PM

HIGH-RESOLUTION PALEO-HYDROLOGIC SPELEOTHEM RECORD FROM CENTRAL NEW YORK, SCHOHARIE COUNTY


KATZ, Sarah A.1, GILLIKIN, David P.1, RODBELL, Donald T.1 and CHENG, Hai2, (1)Geology Department, Union College, 807 Union Street, Schenectady, NY 12308, (2)Department of Earth Sciences, University of Minnesota, 310 Pillsbury Dr. SE, Minneapolis, MN 55455

Stable isotope results of a speleothem collected in 1832 from Gage Caverns in Schoharie County, New York indicate a potential high-resolution record of local hydrologic conditions. Our growth model--generated from 13 U/Th samples taken over the full extent of the growth axis--indicates initial growth beginning ca. 7.9 ka and continuing until 187 BCE. Growth appears to be continuous over this interval, with no hiatuses observed and an average growth rate of 24.195 yr/mm over the sampled 338.5 mm length. Nearly 400 stable isotope samples track carbon (δ13C) and oxygen (δ18O) isotope changes at a precisely dated, sub-centennial resolution. Initial δ18O results show slight cyclicity on a ~500 year scale (through 2.7 ka) with values between -5.42‰ and -4.77‰. Periods of relatively fast growth appear to align with higher δ18O and lower growth rate intervals record more negative δ18O values. Continued analysis of the Gage01 speleothem seeks to integrate our interpretations of Central New York mid- to late-Holocene hydrology with other terrestrial proxy records and historical observations.