Analysis of porewater constituents in sediments collected in the Campeche Hydrocarbon Province in the Southern Gulf of Mexico in 2015

In the Campeche Hydrocarbon province in the southern Gulf of Mexico, large areas of the seafloor are rich in natural gas and highly viscous crude oil. To understand the influence of these hydrocarbons on porewater geochemistry, we cored sediments from specific sites by gravity coring, multicoring and push coring during Meteor Expedition M114-2 in March 2015. Onboard, we retrieved porewater from these samples by Rhizon sampling. In addition, some seawater samples were collected. In the home laboratory, we analyzed the subsamples for silicate, phosphate, ammonium, nitrate, nitrate using a multi-channel nutrient analyzer, for sulfate and chloride using an ion chromatograph, for sulfide using the diamine approach, and we analyzed the isotopic composition of dissolved inorganic carbon using a GasBench coupled to an isotope ratio mass spectrometer.