Discovery and biogeochemistry of asphalt seeps in the North Sao Paulo Plateau, Brazilian Margin.

ABSTRACT: An initial multiple biogeochemical dataset was acquired from the first discovered asphalt seeps in the Brazil margin during deep-sea dive surveys in 2013 using a manned submersible. These surveys were conducted on the outer escarpment of the North São Paulo Plateau. Sediment cores taken from the submersible were processed for pore water and sediment biogeochemistry. The silica concentration, as a chemical geothermometer, showed a steep gradient in the pore water, which indicates the possibility of an active brine system operating in the seepage area. Rare earth elements were used as powerful tracers of chemical processes. Low rare earth element concentrations in both asphalt and Fe-Mn oxyhydroxide-phase sediments suggests that rare earth elements were released during the oil fractionation

SUBMITTER: Jiang K 

PROVIDER: S-EPMC6105600 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature