Oxygen and carbon isotopic composition of Quaternary meteoric carbonates from western and southern Europe: Their role in palaoenvironmental reconstruction

The relationship between environmental conditions and the δ18O and δ13C values of soil and groundwater carbonates in Europe is poorly understood. Consequently, the use of the isotopic composition of these carbonate palaeoclimatic indicators in European sedimentary sequences is restricted. In this study we examine the δ18O and δ13C values of soil and groundwater carbonates from western and southern Europe. In western Europe there is no relationship between carbonate δ18O values and carbonate δ13C values. The δ18O values of soil carbonate appears to be driven by temperature, whilst the δ13C value of soil and groundwater carbonate reflects the persistent dominance of C3 vegetation in this region during the Quaternary. The δ18O and δ13C values of soil carbonates from Spain and Crete show a strong degree of co-variance suggesting that they are being controlled by the same environmental factor. This is suggested to be aridity. δ18O values are controlled by soil moisture evaporation whilst δ13C value is controlled by soil moisture degassing, vegetation abundance and possible C3/C4 vegetation inputs. The paper concludes by highlighting the fact that, although currently under-utilised, the δ18O and δ13C values of soil and groundwater carbonates have a huge potential for providing important palaeoenvironmental information from sites across Europe.