Benthic fluxes of dissolved oxygen, total alkalinity, inorganic carbon and methane were determined in situ by benthic chamber deployments at 9 stations (depth range: 8 to 34 m) on the northeastern near-shore continental shelf of the Gulf of Cádiz (SW Iberian Peninsula) during 3 cruise periods (June 2006, November 2006 and February 2007). Sediment oxygen uptake and dissolved inorganic carbon flu...

Understanding the dynamics and fate of methane (CH 4 ) release from oceanic seepages on margins shelves into water column, quantifying budget its total discharge at different spatial temporal scales, currently represents a major scientific undertaking. Previous works escaping seafloor underlined challenge in both, estimating concentration distribution identifying gradients. In April 2019, Envri...

Introduction: Titan has a massive atmosphere with a pressure at surface level of ~1.5 bars. In the atmosphere the molecular nitrogen N2 is the dominant constituent (~94 percent) and the methane CH4 is the second most abundant component (~5 percent) [1]. The atmosphere of Titan is photochemically active with an efficient production of ethane, ethylene, acetylene and propane as minor components. ...

[1] We report total dissolved inorganic carbon (DIC) abundances and isotope ratios, as well as helium isotope ratios (He/He), of cold seep fluids sampled at the Costa Rica fore arc in order to evaluate the extent of carbon loss from the submarine segment of the Central America convergent margin. Seep fluids were collected over a 12 month period at Mound 11, Mound 12, and Jaco Scar using copper ...

Early diagenesis of marine organic matter dramatically impacts Earth’s surface chemistry by changing the burial potential carbon and promoting formation authigenic mineral phases including carbonate concretions. Marine sediment-hosted concretions tend to form as a result microbial anaerobic diagenetic reactions that degrade methane, some which require an external oxidant. Thus, temporal changes...

Sulfate-driven anaerobic oxidation of methane (AOM) limits the release from marine sediments and promotes formation carbonates close to seafloor in seepage areas along continental margins. It has been established that hydrocarbon seeps are a source methane, dissolved inorganic carbon, organic carbon environments. However, questions remain about contribution deep-sourced sedimentary pool. In thi...