The National Methane Hydrates R&D Program
The DOE/JIP Gulf of Mexico Hydrate Research Cruise
During this expedition we will maintain a log of information relayed from the chief Scientist on the expedition. Whenever possible, images will be displayed along with the text.
April 22 - Day 6 - Status Report
22 April 2005 - On location at Atwater Valley Block 14
Location: On location Atwater Valley Block 14
|
 |
|
Push core taken by ROV |
Science Update: ROV push cores of surface sediments and bottom water samples were recovered at the AT14#1 site, after an unsuccessful first attempt. Additional ROV time was available while waiting for currents to subside to start the AT14#1 LWD hole. The ROV camera showed evidence of seepage on the seafloor around AT14#1, with probable microbial mats and possible patches of carbonate and black sulfides. Two full (20-30 cm) cores and one partial core were recovered. The longer core was divided into three sections for geochemical analysis. The entire core appeared to have gas expansion features, and the top section (0-10 cm) smelled slightly of hydrogen sulfide. Salinity was 44.5 ppt near the surface and increased to 52 ppt in the deeper (20-35 cm) section. Dissolved sulfate was depleted, with 4.7 millimolar concentration in the uppermost section, and only 0.2 mM at 20-35 cm. The plan the for proposed AT13#2 coring well was updated in light of the preliminary LWD results. Seismic amplitude anomalies appeared to coincide with regions of lower resistivity. Proposed coring intervals will target these zones
Plans: Set up the Core Processing Van to be ready for full cores by Sunday. Need designated places for the required equipment (wiping rags, core cutters, endcaps, wire saws, spatulas, gas sampling syringes and vials, thermometers, buckets, Al foil, sample bags, liquid nitrogen containers, and hydrate pressurization containers). Update coring program for proposed AT14#2 when preliminary LWD results are available.
Planning and Data Sheet for AT14 - #1 [PDF-10KB]
Includes Scientific objectives for this drill site.
Photos:
Day 6 Photo Gallery - Working with push cores and ROV photos of sample collection at AT 14
Day 4 Photo Gallery - Remotely Operated Vehicle (ROV), Sampling, Core Handling
Day 3 Photo Gallery - Preparation for Drilling
Day 2 Photo Gallery Loading the Uncle John [PowerPoint]
The drill ship out to sea - Setting up the lab [PowerPoint]
|
ABOUT NETL
Deepwater Technology