Sediment samples were run on a Carlo Erba 1108 elemental analyzer with a Costech zero-blank autosampler (Costech Analytical Technologies, Inc., USA) interfaced to a Thermo Finnigan Delta Plus XP IRMS (Thermo Finnigan, USA).
Instruments that quantify carbon, nitrogen and sometimes other elements by combusting the sample at very high temperature and assaying the resulting gaseous oxides. Usually used for samples including organic material.