Johnson, Joel E. et al. (2005): North-south variability in the history of deformation and fluid venting across Hydrate Ridge, Cascadia Margin

Leg/Site/Hole:
ODP 204
Identifier:
2007-035091
georefid

10.2973/odp.proc.sr.204.125.2006
doi

Creator:
Johnson, Joel E.
Oregon State University, College of Oceanic and Atmospheric Sciences, Corvallis, OR, United States
author

Goldfinger, Chris
Christian-Albrechts-Universitaet zu Kiel, Federal Republic of Germany
author

Trehu, Anne M.
Joint Oceanographic Institutions, United States
author

Bangs, Nathan L. B.
University of Texas at Austin, United States
author

Torres, Marta E.
University of Leicester, United Kingdom
author

Chevallier, Johanna
Eastern Kentucky University, United States
author

Identification:
North-south variability in the history of deformation and fluid venting across Hydrate Ridge, Cascadia Margin
2005
In: Trehu, Anne M., Bohrmann, Gerhard, Torres, Marta E., Rack, Frank R., Bangs, Nathan L., Barr, Samantha R., Borowski, Walter S., Claypool, George E., Collett, Timothy S., Delwiche, Mark E., Dickens, Gerald R., Goldberg, David S., Gracia, Eulalia, Guerin, Gilles, Holland, Melanie, Johnson, Joel E., Lee, Young-Joo, Liu, Char-Shine, Long, Philip E., Milkov, Alexei V., Riedel, Michael, Schultheiss, Peter, Su Xin, Teichert, Barbara, Tomaru, Hitoshi, Vanneste, Maarten, Watanabe, Mahito, Weinberger, Jill L., Boetius, Antje, Brockman, Fred J., Deyhle, Annette, Fehn, Udo, Flemings, Peter B., Girguis, Peter R., Heesemann, Martin, Joye, Samantha B., Lorenson, Thomas D., Mills, Christopher T., Musgrave, Robert J., Popa, Radu, Ussler, Bill, Wilkes, Heinz, Winckler, Gisela, Winters, William J., Proceedings of the Ocean Drilling Program; scientific results; drilling gas hydrates on Hydrate Ridge, Cascadia continental margin; covering Leg 204 of the cruises of the drilling vessel JOIDES Resolution; Victoria, British Columbia, Canada, to Victoria, British Columbia, Canada; Sites 1244-1252; 7 July-2 September 2002
Texas A&M University, Ocean Drilling Program, College Station, TX, United States
204
Hydrate Ridge is an accretionary thrust ridge located on the lower slope of the central Cascadia convergent margin. Structural mapping based on two-dimensional and three-dimensional multichannel seismic reflection profiles and gridded bathymetry coupled with deep-towed sidescan sonar data and Ocean Drilling Program (ODP) biostratigraphy suggests that seafloor fluid venting patterns are likely controlled by the seaward-vergent (SV) structural style at northern Hydrate Ridge (NHR) and by the dominantly landward-vergent (LV) structural style at southern Hydrate Ridge (SHR). North-south structural variability across Hydrate Ridge is coincident with the seafloor authigenic carbonate distribution, which varies from aerially extensive authigenic carbonate crusts at NHR to a minor focused occurrence of authigenic carbonate at SHR. The older stratigraphy exposed at the seafloor at NHR (>1.6-1.7 Ma) has likely been subjected to a longer history of sediment compaction, dewatering, and deformation than the younger slope basin strata preserved at SHR (1.7 Ma to recent), suggesting the extent of carbonates at NHR may result from a longer history of fluid flow and/or more intense venting through a more uplifted, lithified, and fractured NHR sequence. Furthermore, recent work at SHR shows that the major seafloor fluid venting site there is fed by fluid flow through a volcanic ash-bearing turbidite sequence, suggesting stratigraphic conduits for fluid flow may be important in less uplifted, LV-dominated portions of Hydrate Ridge. In addition, the variability in structural style observed at Hydrate Ridge may have implications for the distributions and concentrations of fluids and gas hydrates in other accretionary settings and play a role in the susceptibility of accretionary ridges to slope failure.
English
Coverage:Geographic coordinates:
North:44.3500
West:-125.0900East: -125.0400
South:44.3400

Oceanography; acoustical methods; bathymetry; carbonates; Cascadia subduction zone; deformation; East Pacific; fluid dynamics; geophysical methods; geophysical profiles; geophysical surveys; Hydrate Ridge; Leg 204; North Pacific; Northeast Pacific; Ocean Drilling Program; ocean floors; Pacific Ocean; seismic methods; seismic profiles; sonar methods; surveys; tectonics; variations;

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