High-resolution trace element and stable/radiogenic isotope profiles of late Pleistocene to Holocene speleothems from Dim Cave, SW Turkey

Ünal-Imer E., Shulmeister J., Zhao J., Uysal I. T., Feng Y.

Palaeogeography, Palaeoclimatology, Palaeoecology, vol.452, pp.68-79, 2016 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 452
  • Publication Date: 2016
  • Doi Number: 10.1016/j.palaeo.2016.04.015
  • Journal Name: Palaeogeography, Palaeoclimatology, Palaeoecology
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.68-79
  • Keywords: Dim Cave, Eastern Mediterranean, Speleothem geochemistry, Sr-isotope ratio, Stable isotope ratio, SW Turkey
  • Middle East Technical University Affiliated: No


Multiple climate-sensitive trace element/Ca and stable isotope (O and C) profiles derived from Dim Cave speleothems (S-SW Turkey) provide evidence of climatic changes and define a series of palaeohydrological conditions for the period ~10-90 kyr. Dim Cave speleothem Mg/Ca, Sr/Ca, U/Ca, Ba/Ca, and Y/Ca ratios demonstrate similar patterns over glacial-interglacial scales, in agreement with δ18O and δ13C records. Three episodes of more positive moisture balance (71-63 kyr, 51-40 kyr, and 18-10 kyr) were observed based on Y/Ca (and to a lesser extent Zr/Ca), 87Sr/86Sr ratios, calcite micromorphology, and growth rates. Increasing concentrations of Y, Zr (and U) and elevated 87Sr/86Sr ratios are attributed to enhanced levels of terrestrial input during these periods. Correlations between δ13C, δ18O and Mg/Ca during 40-18 kyr (corresponding with the lowest growth rate of ~0.8 mm/kyr), 63-51, and 80-71 kyr (relatively low growth rates), as well as co-varying and enhanced Mg/Ca, Sr/Ca, and to a lesser extent Ba/Ca, ratios point to the prior calcite precipitation, wall rock interaction, and preferential dolomite dissolution over calcite in the host dolomitic limestone during these periods. This relationship suggests that water-rock interactions are maximised during episodes of slower drip rates of water through the karst under drier conditions. Chondrite-normalised rare earth element and yttrium (REY) patterns of the stalagmites reveal seawater signatures closely linked to the dolomitic limestone. Excluding the aragonite formation during ~80-75 kyr, which is an autogenic effect, trace element/Ca ratios appear to respond to millennial scale global cooling periods such as Heinrich events.