||Nouze Herve1, Cosquer Emmanuel1, Collot Julien1, 2, Foucher Jean-Paul1, Klingelhoefer Frauke1, Lafoy Yves2, Geli Louis1
||1 : IFREMER, Dept Marine Geosci, F-29280 Plouzane, France.
2 : Geol Survey New Caledonia, Dept Ind Mines & Energy New Caledonia, Noumea 98845, New Caledonia.
||Marine Geology (0025-3227) (Elsevier), 2009-10 , Vol. 266 , N. 1-4 , P. 80-90
|WOS© Times Cited
||Stratigraphy, Gas hydrates, Geophysics, Southwest Pacific, Fairway Basin, BSR
||High-resolution reflection and refraction seismic data were collected in 2004 to investigate, in further detail than allowed by pre-existing low resolution seismic data, the nature of a Bottom Simulating Reflector (BSR) that extends over a broad area of the Fairway Basin, a rifted, continental structure located on the eastern flank of the Lord Howe Rise, to the southwest of New Caledonia. Two main reflectors are documented: the shallower (RN) mimics the seafloor and has a negative polarity while the deeper (RP) does not always mimic the seafloor and has a positive polarity. Using the existing regional seismic lines, we can show that reflector RN can be continuously followed up to DSDP 208 drill hole site. Reflector RP is discontinuous and cannot be traced to DSDP 208. Based on DSDP 208 stratigraphic data, Reflector RN is assigned to the Eocene/Oligocene regional unconformity; reflector RP is interpreted in terms of a diagenetic BSR, likely related to an Opal-A/Opal-CT transition front. Heat flow data collected in 2006 suggest that reflector RP lies too deep to be related to methane hydrates, strengthening our interpretation that RP is of diagenetic origin.