Accession Number:

ADA411571

Title:

VENTFLUX2: Single Channel Seismics, Piston Coring, and CTD Casts Associated with Gas Hydrates Offshore Vancouver Island. Report of Cruise PG01-003 C.C.G. Vessel John P. Tully, 23 July-12 August 2001. Volume 1: Opeations

Descriptive Note:

Interium rept.

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC

Report Date:

2003-02-08

Pagination or Media Count:

125.0

Abstract:

Cruise PGC00-003 was a collaborative experiment between the University of Victoria, the Geological Survey of Canada, and the Naval Re- search Laboratory. The program focused on seafloor vents that may be sites of significant fluid and methane flux. There were six sites with different indicators of fluid flow selected for this cruise 1 Bullseye vent hydrate had been recovered in this region in four piston cores collected during the 2000 VentFlux cruise. 2 Cucumber Ridge numerous tube worms and clams had been observed and collected during ROPOS dives in May 2001. 3 FishBoat site in November 2OOO, a commercial trawler dragged up one to two tons of hydrate at this site in Barclay Canyon in water depth of 800 m 4 ShallowPlume sites apparent methane plumes were observed on the continental shelf edge in water depths of -200 m. The plumes were identified on 28 MHz sounder records. 5 Nootka Fault Zone swath bathymetry collected in July 2001 found two mud volcanoes in the open ocean basin in water depths of 2600 m. 6 NorthernFault Zone Located -5 km northwest of ODP Site 8889, this was detected as a northeast-southwest linear zone of seismic blazing on 1999 3D COAMS data. Sites 1 to 5 were targets for piston coring and water column sampling during daytime operations. Sites 2 to 6 were high resolution single channel seismic grids during nighttime operations.

Subject Categories:

  • Physical Chemistry
  • Geology, Geochemistry and Mineralogy
  • Reciprocating and Rotating Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE