Six dive days were planned in the axes of central coast canyons north and south of Monterey Canyon and its primary tributaries. The primary targets are Ano Nuevo, Pioneer, Lucia, Partington, and Sur canyons. The primary MBARI objective of these dives was to determine the recent sediment transport activity in each of these canyons with specific attention to tracking DDT residues. In addition, the USGS project interests were to determine which of the canyons, if any, show evidence for recent transport of coarse sediment and to examine the stratigraphy of the canyon walls on selected dives. Dive sites were based on MBARI and NOAA multibeam. The intention was to collect vibracore and push core along transects across the center of the axial channel and locally up the adjacent canyon walls. Mechanical problems with the Western Flyer limited the cruise to five days.
Description
Monterey Bay Aquarium Research Institute,United States Geological Survey, Menlo Park, California. Chief Scientist: Charlie Paull, MBARI. Dive and Sampling data (ROV) of field activity W-1-06-MB in Submarine canyons of the central California coast from 04/27/2006 to 05/01/2006
Location
Submarine canyons of the central California coast
Summary
1730/JD117 R/V Western Flyer departs Moss Landing. ~1830/JD117 Begin test of CTD/rosette sampler in upper Monterey Canyon (MBARI operation) 2200/JD117 On station for the first ROV dive of the expedition TIBURON Dive T-971 in Ano Nuevo Canyon, one of the main tributaries to the Ascension Canyon 0153/JD121 Complete final ROV Dive T979, in Partington Canyon. 1430/JD121 A shaft seal leak on one of the main screws could not be fixed at sea. The ROV operations are suspended and the Western Flyer heads for Moss Landing to initiate repairs. This is the end of the science operations. The Western Flyer arrives in Moss Landing at 2245/JD121. Refer to the Operation Log for details. A total of 9 TIBURON ROV dives were completed by the end of the fourth day of operations on JD121. Of these dives, 1 was in Ano Nuevo Canyon, 4 were Pioneer Canyon, 1 was in a slope gulley north of Pioneer Canyon, 1 was in Sur Canyon, and 2 were in Partington Canyon. During these dives, 18 vibracores were obtained that will come to the USGS for MST logging, photography, description and archiving. Other cores that will come to the USGS are 4 vertical push cores for stratigraphic purposes that will be logged before splitting for photography and description. Push cores not saved in their original polycarbonate core liners include 12 horizontal push cores, which were taken from vertical or near-vertical outcrops and 6 samples from vertical push cores whose upper sections were sampled for geochemical analyses. The bottom sections of these cores were split after extruding, photographed on board the vessel, and are stored in plastic ziplock bags. All primary objectives of the cruise were attained by dives in the canyons noted above, but the failure to sample Lucia Canyon and the Sur Canyon downstream of its confluence with Partington Canyon leaves an incomplete picture of the sediment transport history in these conduits.
Info derived
Extensive sea-floor video coverage to identify benthic fauna, active methane gas vents, etc. Sediment samples will be used for isotopic age determinations, stable-element isotopic studies, benthic-foraminifera populations, and sediment stratigraphy (for canyon/fan channel dive sites).
Comments
(1) Station IDs reflect the Tiburon dive numbers set by MBARI. (2) Sample numbers for the push cores are generally not consecutive but reflect permanent labels on coring and other devices that are randomly chosen before each dive, and many of the push cores are reused in later dives. USGS sample protocol could not used during dives except for the Activity ID (W-1-05-SC). (3) Sample numbers recorded in FACS reflect only those samples that will be brought to the USGS for logging, description, and, in most cases, archiving. (4) Water samples collected by CTD/rosette sampler are not entered in FACS log because samples are processed on board for an MBARI program. ROV Tiburon and CTD/rosette sampler (all MBARI equipment). Tiburon will be used to map and sample the sea floor (see Purpose and Goals above). The CTD/rosette sampler is for detection of methane gas in the water column within the canyons generally at the ROV dive sites.
Staff information imported from InfoBank
Charlie Paull
Bill Ussler
Patrick Whaling
Doug Conlin
Chris Preston
Bill Normark
Mary McGann
Chris Gutmacher
Anne Bernhardt
Angela Hessler
B.J. Reynolds
Mark Talkovic
Randy Pricket
Brian Schaefer
Buzz Scott
Ian Young
Darrell Palmer
Patt Duffy
Matt Tanner
Tim Chiefy
Derek Greenwood
Lance Wardle
Aaron Glass
Dan Chamberlin
Dan Benvenuti
