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.

May 5 - Day 19 - Status Report

5 May  - Coring on mounds at Atwater Valley Block 14 - moving to Keathley Canyon

Location: In transit from Atwater Valley to Keathley Canyon

Unloading pressure core

Science Update: The depth interval 0-29 mbsf was cored late Wednesday and early Thursday at mound site ATM2 (27°56'11.60”N, 89°16'47.00”W). Three Fugro Hydraulic Piston Corer (FHPC) cores were taken in the upper portion followed by two HYACE Rotary Corer (HRC) pressure cores and a final Fugro Pressure Corer (FPC) pressure core near the base of the cored section. The FHPC cores recovered sediment from the upper 24 meters beneath the seafloor. The pore waters showed a similar pattern of salinity variation as the cores from the ATM1 site. IR imaging showed that colder zones of the cores frequently coincided with gas expansion voids. Closely spaced samples for pore water chemistry were collected adjacent to these cold zones to test for pore water freshening. Salinities were lowest just next to, and increased with distance away from the cold zones. These observations are consistent with gas hydrate having been present in the sediment and decomposing prior to sampling. The two deeper HRC pressure cores did not recover any sediment. The FPC pressure core recovered sediment from 27-28 meters under pressure. This pressurized core (ATM2-6P) was successfully transferred to an aluminum storage chamber, and 2D X-ray images show discrete zones of low-density (about 1 g/cc) material in the core. More detailed analysis of 3D CT imaging is currently in process. The core is being maintained in stable condition while improvements are being made on the cold van to create an environment in which the full array of shipboard experiments on pressurized cores can be conducted.

Plans: Continue working up results from the previous three coring sites in Atwater Valley and refine the Logging While Drilling (LWD), coring and wireline logging plans for KC151 #1 and #2.

A time-lapse digital camera assembly installed on the seafloor recorded hourly images of the growth or dissolution of an exposed hydrate deposit. These photos were taken during a research expedition to the northern Gulf of Mexico (Green Canyon 185, known as Bush Hill) in June of 2002.  This expedition was taken as part of a study to determine the potential impacts of gas hydrate instability in terms of the release of methane into seafloor sediments. DOE/NETL project DE-FC26-02NT41328

Planning and Data Sheet for AT14#4 (ATM2)   [PDF-10KB] 
Includes Scientific objectives for these drill sites

Maps of drill sites - Shows Keathley Canyon and Atwater Valley locations

Special Report - core handling

Special Report - Conventional Wireline Logging Operations in the Gulf of Mexico Gas Hydrate JIP Drilling Program - Timothy Collett, USGS

Photos:
Day 16 Photo Gallery  - Photos by NETL scientist showing core analyses process and equipment
Day 13 Photo Gallery  - Photos by NETL scientist showing drilling preparation
Day 12 Photo Gallery  - Photos by NETL scientist showing core retrieval and processing
Day 10 Photo Gallery  - Pressurized core prior to transfer to lab and seabed frame preparation
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]