https://doi.pangaea.de/10.1594/PANGAEA.995258Rooze, JurjenJurjenRooze0000-0001-5429-9878Leibniz Institute for Baltic Sea Research, WarnemündeSansjofre, PierrePierreSansjofreSorbonne Université, Paris, FranceMeile, ChristofChristofMeileUniversity of GeorgiaBöttcher, Michael ErnstMichael ErnstBöttcher0000-0002-8877-0303Leibniz Institute for Baltic Sea Research, WarnemündeJouet, GwenaelGwenaelJouet0000-0002-2178-2115IfremerPastor, LucieLuciePastor0000-0001-9732-8907PANGAEA2026carbonatesDiagenesisGas seepsironMadagascarMarine sedimentMethanepore waterRadiocarbonStable isotopesSulfurEvent labelOptional event labelDEPTH, sediment/rockCarbon, organic, totalδ13C, total organic carbonIron, dithionite extractableIron disulfideδ34S, FeS2CalciteHigh magnesium calciteAragoniteδ13Cδ18OIronAluminiumMethane, dissolvedδ13C, methaneSulfate, dissolvedHydrogen sulfide, dissolvedIron, dissolvedAlkalinity, totalManganese, dissolvedCalcium, dissolvedMagnesium, dissolvedδ13C, dissolved inorganic carbonPorosity, totalδ13C, carbonateδ18O, carbonateδ13C, organic carbonCavity ring-down spectroscopy (CRDS) isotopic water analyzer, Picarro Inc., L2130-i; coupled to a Combustion Module (CM), Picarro Inc., A020Cavity ring-down spectroscopy (CRDS), isotopic water analyzer, Picarro Inc., L2101-iInductively coupled plasma-atomic emission spectrometer (ICP-AES), HORIBA, ULTIMA 2Chromium reducible sulfur extraction according to Canfield et al. (1986)Elemental analyzer - isotope ratio mass spectrometer (EA-IRMS), Europa Scientific, ANCA-SL/20–20X-Ray Diffractometer, Bruker Corporation, D8 ADVANCEIsotope ratio mass spectrometer (IRMS), Thermo Finnigan, MAT 253; coupled with Gas bench II, Thermo Fisher ScientificWavelength Dispersive X-Ray Fluorescence (WDXRF), Bruker Corporation, S8 TigerWave-length dispersive X-ray fluorescence spectroscopy (WD-XRF)Flame Ionization Detector (FID), Perichrom, PR2100Cavity ring-down spectrometer (CRDS), Picarro, G2201-iIon chromatograph, Dionex Corporation, ICS-5000Cline method according to Cline (1969)Inductively coupled plasma mass spectrometer (ICP-MS), ThermoFisher Scientific, Element XRAutomatic titrator, Metrohm, 888 Titrando coupled with pH electrodeIon chromatograph, Thermo Scientific, Dionex ICS-5000GasBench II-IRMS, MAT 253, Thermo ScientificGravimetric analysisPAMELA-MOZ4Pourquoi Pas ? (2005)2015-11-14T00:00:00Dataset10.1016/j.gca.2026.04.02010.1016/0009-2541(86)90078-110.4319/lo.1969.14.3.045410.1007/BF00000230704 data pointstext/tab-separated-valuesCreative Commons Attribution 4.0 InternationalThis dataset contains biogeochemical solid-phase and pore water data from sediment core MOZ4-CSF04 (named S2-G in the publication cited below), collected on 14 November 2015 during the PAMELA-MOZ4 oceanographic cruise offshore northwest Madagascar. This core was analyzed to assess the impact of fluid seepage on sediment biogeochemistry and diagenetic processes. Solid-phase parameters comprise total organic carbon (TOC), stable carbon isotopes of organic matter, reactive iron phases (dithionite-extractable Fe), pyrite content (FeS2) and its sulfur isotopic composition (δ34S), carbonate mineralogy (calcite, high Mg-calcite, aragonite), and stable carbon and oxygen isotopes of background carbonates and concretions, as well as δ13C of organic carbon associated with concretions. Bulk elemental concentrations of Fe and Al were determined by X-ray fluorescence (XRF). Pore water analyses include dissolved methane (CH4), sulfate (SO4), sulfide (H2S), dissolved iron (Fe), manganese (Mn), calcium (Ca), magnesium (Mg), total alkalinity (TA), and stable carbon isotopic compositions of methane and dissolved inorganic carbon (DIC). The dataset also includes porosity measurements.45.951833-15.3705Indian Ocean