Sampling was conducted during the R/V Meteor cruise M74/2, on 7th to 28th October 2007, in the Arabian Sea over the Pakistan shelf. Four stations ranging from 360 to 1430 m were selected for detailed sampling and sediment incubations. For analyses of dissolved iron and sulfide, sediment cores were sampled on board with rhizomes at 1 cm (sediment depth 0-5 cm) and 2 cm intervals (sediment depth 5-30 cm). Subsequently the obtained pore water was analyzed for Fe2+ and HS-on board according to Grasshoff et al. (1999) and Cline (1969), respectively.