Assessment of climatic influences on 14C activity in a Holocene stalagmite from Flores, Indonesia

Abstract

In the last decade, a number of speleothem studies have used radiocarbon dating to address a range of paleoclimate problems. These have included the use of the bomb pulse to anchor chronologies over the last 60 years (Mattey et al 2008), the combining of U-series and radiocarbon measurements to improve the radiocarbon calibration curve (Beck et al. 2001), and linking atmospheric radiocarbon variations with climate changes (McDermott et al. 2008). Central to a number of these studies is how to constrain, or interpret variations in, the amount of radioactively dead carbon (i.e. the dead carbon fraction, or DCF) that contributes to a speleothem radiocarbon measurement. In this study, we use radiocarbon measurements, stable isotope and trace element geochemistry, and U-series ages to examine DCH variations between 2.4 and 2.8 ka in a previously studied (Griffiths et al. 2009; 2010) speleothem from Liang Luar, Flores, Indonesia.