Data/hora: 02/06/2024 01:18:54

Provedor de dados: | 5
País: | France
Título: | Gas hydrate distributions in sediments of pockmarks from the Nigerian Margin - Results and interpretation from shallow drilling
Autores: | Wei, Jiangong; Pape, Thomas; Sultan, Nabil; Colliat, Jean-louis; Himmler, Tobias; Ruffine, Livio; De Prunele, Alexis; Dennielou, Bernard; Garziglia, Sebastien; Marsset, Tania; Peters, Carl A.; Rabiu, Abdulkarim; Bohrmann, Gerhard.
Data: | 2015-01
Ano: | 2015
Palavras-chave: | Gas hydrate; Pockmark; Chloride profile; Infrared thermal imaging; Fluid flow; Nigerian continental margin; MeBo drill rig.
Resumo: | A joint research expedition between the French IFREMER and the German MARUM was conducted in 2011 using the R/V Pourquoi pas? to study gas hydrate distributions in a pockmark field (1141 – 1199 meters below sea surface) at the continental margin of Nigeria. The sea floor drill rig MeBo of MARUM was used to recover sediments as deep as 56.74 meters below seafloor. The presence of gas hydrates in specific core sections was deduced from temperature anomalies recorded during continuous records of infrared thermal scanning and anomalies in pore water chloride concentrations. In situ sediment temperature measurements showed elevated geothermal gradients of up to 258 °C/km in the center of the so-called pockmark A which is up to 4.6 times higher than that in the background sediment (72 °C/km). The gas hydrate distribution and thermal regime in the pockmark are largely controlled by the intensity, periodicity and direction of fluid flow. The joint interaction between fluid flow, gas hydrate formation and dissolution, and the thermal regime governs pockmark formation and evolution on the Nigerian continental margin.
Tipo: | Text
Idioma: | Inglês

Identificador:

http://archimer.ifremer.fr/doc/00213/32382/30846.pdf

DOI:10.1016/j.marpetgeo.2014.09.013

http://archimer.ifremer.fr/doc/00213/32382/

Editor: | Elsevier Sci Ltd
Formato: | application/pdf
Fonte: | Marine And Petroleum Geology (0264-8172) (Elsevier Sci Ltd), 2015-01 , Vol. 59 , P. 359-370

Fonte:

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