10.1594/PANGAEA.992687Santos, Felipe RodriguesFelipe RodriguesSantos0000-0001-8756-5036Lourenço, Rafael AndréRafael AndréLourençoTaniguchi, SatieSatieTaniguchiMartins, César de CastroCésar de CastroMartinsWainer, Ilana E K CIlana E K CWainer0000-0003-3784-623XMahiques, Michel MichaelovitchMichel MichaelovitchMahiques0000-0002-5249-5610Nagai, Renata HanaeRenata HanaeNagai0000-0002-1358-5074Figueira, Rubens César LopesRubens César LopesFigueira0000-0001-8945-4540Bouloubassi, Ioanna DIoanna DBouloubassiBicego, Marcia CMarcia CBicegoPANGAEA2026alkanesLa Plata Riversouthern Brazilian marginvegetation changesEvent labelLatitude of eventLongitude of eventDate/Time of eventElevation of eventAGEn-Alkanes, sum, per unit sediment massSum n-alkanes C25-C33n-Alkanes, average chain lengthAverage chain length, n-Alkanes, C27-C33Carbon Preference IndexAquatic n-alkane proxyGravity corerAge, 14C calibratedsummarizedGas chromatography - Flame Ionization Detection (GC-FID), Agilent Technologies, HP7890BCalculated according to Poynter (1989)Calculated according to Bray and Evans (1961)Calculated2019-06-02T12:20:00/2019-06-02T13:22:00Dataset10.1214/11-BA61810.1016/0016-7037(61)90069-210.1017/RDC.2020.6810.1007/978-94-009-0995-3_181296 data pointstext/tab-separated-valuesCreative Commons Attribution 4.0 InternationalThis dataset presents concentrations of long-chain n-alkanes (nC25–nC33) and derived molecular indices, including Carbon Preference Index (CPI), Average Chain Length (ACL), and Paq, from Holocene marine sediment cores MDBT 557 and MDBT 561, recovered from the southern Brazilian continental shelf. Lipid biomarkers were extracted using organic solvents, purified by column chromatography, and quantified by gas chromatography with flame ionization detection (GC-FID), with surrogate standards used to assess analytical recovery. These data characterize variations in terrigenous organic matter input, vegetation-related signals, and hydrological conditions affecting the continental margin during the Holocene.-52.21-51.3-33.79-33.27Brazilian southeastern continental shelfSão Paulo Research Foundationhttps://doi.org/10.13039/50110000180717/20344-7Mudbelts of Southern and Southeast Brazil: Implications on anthropogenic influences on the marine environment