-notation with respect to the SO2-based Vienna-Canyon-Diablo troilite (V-CDT) standard (Gonfiantini et al., 1995) according to (R = 34S/32S):
Interstitial water samples were squeezed from whole-round samples immediately after retrieval of the cores with the standard titanium-stainless steel ODP squeezer (Manheim and Sayles, 1974). The retrieved pore waters were subsequently analyzed on board the JOIDES Resolution for concentrations of major and minor constituents, including sulfate and chloride (Carter, McCave, Richter, Carter, et al., 1999), by using methods described by Gieskes et al. (1991). Sulfur isotope measurements of dissolved sulfate were performed on pore waters previously used for shipboard alkalinity determinations. The sulfate was precipitated quantitatively as BaSO4 by the addition of a barium chloride solution, washed several times with deionized water, and dried at 110°C. Sulfur isotope ratios (34S/32S) were analyzed by combustion isotope ratio-monitoring mass spectrometry (Giesemann et al., 1994; Böttcher et al., 1998). After total conversion of barium sulfate to SO2 via flash combustion in an elemental analyzer (Carlo Erba EA 1108), sample and standard gas were introduced into a Finnigan MAT 252 gas mass spectrometer via a Finnigan MAT Conflo II interface. Stable isotope ratios 34S/32S are given in the -notation with respect to the SO2-based Vienna-Canyon-Diablo troilite (V-CDT) standard (Gonfiantini et al., 1995) according to (R = 34S/32S):
34S(
) = [Rsample/(RV-CDT - 1)] x 103.
Replicate measurements agreed within ±0.2. Solid-phase total reduced inorganic sulfur was extracted from selected dried squeeze-cake sediments by hot distillation with acidic chromium(II)chloride solution (Canfield et al., 1986; Fossing and Jørgensen, 1989). This fraction includes sedimentary metal sulfides (essentially pyrite [FeS2]) and minor primary elemental sulfur. Minor secondary sulfur may also have been formed as an oxidation product of acid-soluble iron sulfides during drying of the sediment samples.
