FN Archimer Export Format
PT J
TI Seafloor facies related to upward methane flux within a Giant Pockmark of the Lower Congo Basin
BT 
AF GAY, Aurelien
   LOPEZ, M
   ONDREAS, Helene
   CHARLOU, Jean-Luc
   SERMONDADAZ, G
   COCHONAT, Pierre
AS 1:1;2:2;3:3;4:3;5:4;6:3;
FF 1:;2:;3:PDG-DOP-DCB-GM-LGM;4:PDG-DOP-DCB-GM-LGM;5:;6:PDG-DPS;
C1 NOCS, Southampton SO14 3ZH, Hants, England.
   Univ Montpellier 2, Lab Dynam Lithosphere, F-34095 Montpellier 05, France.
   IFREMER, Dept Geosci Marines, F-29280 Plouzane, France.
   TOTAL, F-64018 Pau, France.
C2 NOC, UK
   UNIV MONTPELLIER, FRANCE
   IFREMER, FRANCE
   TOTAL, FRANCE
SI BREST
   SIEGE
SE PDG-DOP-DCB-GM-LGM
   PDG-DPS
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-europe
   copubli-univ-france
IF 2.029
TC 82
UR https://archimer.ifremer.fr/doc/2006/publication-1114.pdf
LA English
DT Article
CR BIOZAIRE
   ZAIANGO-BIOL2
   ZAIANGO1
   ZAIANGO2
   ZAIANGOROV
BO Thalassa
   L'Atalante
DE ;BIOZAIRE;ZAIANGO;Palaeochannel;Hydrates;Chemosynthesis;Seafloor facies;Fluid migration;Pockmark
AB The origin of the cold fluid venting from a Giant Pockmark within the Lower Congo Basin has been elucidated based upon results of precise mapping, submersible dives, gravity coring and isotopic analyses realized under a TOTAL-IFREMER cooperative project (ZAIANGO and BIOZAIRE projects). During four dives of the IFREMER ROV-Victor 6000, the bottom was filmed, hard and soft samples were lifted from the sediment, and water samples were collected with a CTD-rosette system. The detailed dip map shows that the 800 in wide Giant Pockmark is a composite feature due to the coalescence of multiple 100 in wide depressions that displays a broad range of biological, mineralogical and chemical features on the seafloor, leading to a seafloor anomaly recorded on the multibeam imagery. Methane-rich fluids migrating through the sedimentary column from a buried palaeochannel clearly react with the sulphate-rich circulating sea water to produce hydrogen sulphide and bicarbonate ions. This situation leads to a concentrical arrangement of the sedimentary facies, with methane-related features in the centre and sulphide-related features at the periphery. This organization is correlated with high levels of methane (up to 20 mu mol/l) measured in the centre of the Giant Pockmark, responsible for the crystallization of gas hydrates at the bottom. In this model, the concentrical organization of mineralogical and biological features reflects a geochemical partitioning related to the peripheral progressive mixing of the methane flux.
PY 2006
PD FEB
SO Marine Geology
SN 0025-3227
PU Elsevier
VL 226
IS 1-2
UT 000235272200006
BP 81
EP 95
DI 10.1016/j.margeo.2005.09.011
ID 1114
ER

EF