Expedition UT-GOM2-2 General Information
Location: Terrebonne Basin
Sites: WR313 H002 and WR313 H003
Dates: July 30 to September 28, 2023
Chief Scientist: Peter Flemings
Sponsor: U.S. Department of Energy
Expedition Summary & Scientific Objectives
The University of Texas at Austin (UT), performed the UT-GOM2-2 drilling and coring expedition in the Terrebonne Basin, outer continental shelf.
The UT-GOM2-2 expedition sampled and analyzed the physical, chemical, and biological properties of the hydrate-bearing layers. Novel technology, developed during the project, was used to extract cores from a mile beneath the ocean and study those cores in laboratories worldwide, while keeping the samples under their original pressure. Through sampling of the microbes, and analysis of the surrounding pore fluid, we will illuminate the depths and rates at which microbes are generating methane beneath the seafloor. Our analyses will inform biological, geochemical, and geomechanical models to constrain the potential for gas hydrates as an energy resource. The results will illuminate the origin, dynamic behavior, and response of this system to perturbation.
We drilled and cored two vertical wells to ~9,600 ft below sea level in Terrebonne Basin, Walker Ridge Block 313. We spent up to 35 days at sea mobilizing, executing and demobilizing. We spent an additional 14 days performing dockside analysis to complete the analysis of the recovered core.
With the samples and measurements acquired, we will continue to characterize the Orange sand and the Upper Blue sand hydrate reservoirs and their bounding units, and determine the high resolution geochemical, geobiological, and sedimentary profiles in the upper 150 feet below the sea floor (mbsf).
We used Geotek’s Pressure Core Analysis and Transfer System (PCATS) to log and X-Ray image the pressure cores. PCATS was also be used to subsample the recovered pressure cores at hydrate-stable conditions and to transfer samples to pressurized storage chambers. Onboard and dockside, subsamples underwent quantitative degassing to determine dissolved methane and hydrate concentrations. Pressure core in storage chambers were transported to UT’s Jackson School of Geosciences and stored at the UT Pressure Core Center.
Conventional cores were processed on board and dockside. Onboard, sections of conventional and depressurized core were cut for microbiology and pore water analysis. Dockside sections were cut for moisture and density (MAD) and geomechanical analysis. Onboard, sections for pore water analysis were squeezed and ephemeral pore water measurements were completed on board. Preserved pore water samples were shipped to the University of Washington for analysis. Microbiology samples were sent to Oregon State University and other institutions for analysis. MAD samples were sent to Tufts University for analysis.
The conventional and depressurized core underwent CT scanning, Geotek MSCL whole core logging, core splitting, split core scanning, and primary litho- and biostratigraphy. Subsamples of split core were shipped to the University of New Hampshire, UT, and others for secondary litho- and biostratigraphy. Split core archival and working halves were placed in long term cold storage at UT.
The Preliminary Expedition Report was issued in September of 2024. The Expedition Report will be published in 2025. We are eager to support hydrate science by the broader community and requests for data and/or samples can be made to UT.
Prospectus
- Download the UT-GOM2-2 Prospectus: Science and Sample Distribution Plan (V2.3) | PDF
Operations Plan
- Download the UT-GOM2-2 Operations Plan (rev. 2.3) | PDF
Bibliography
- Download the UT-GOM2-2 Pre-Expedition Bibliography | PDF
Expedition Blog
Jackson School Science Writer Monica Kortsha and videographer Drew Ott joined the team to document the expedition and tell the story.
Media Inquiries
If you are a member of the media looking for more information on the expedition, please contact:
Anton Caputo
Director of Communications, UT Jackson School for Geosciences
Email: anton.caputo@jsg.utexas.edu
Office: (512) 232-9623