The U.S. Department of Energy’s (DOE) Office of Fossil Energy and Carbon Management (FECM) and DOE’s National Energy Technology Laboratory (NETL) are working with international and domestic partners to investigate the resource potential of gas hydrates within the Prudhoe Bay Unit (PBU) on the Alaska North Slope. The primary mission of DOE’s gas hydrates research and development (R&D) program is to advance the scientific understanding of gas hydrates as they occur in nature so their resource potential and role in climate change can be fully understood.

Gas hydrates are naturally occurring combinations of natural gas and water that form in relatively cold temperatures and relatively high pressures. They are known to occur in abundance on the Alaska North Slope, as well as in the shallow sediments of deepwater continental margins around the world—most notably in the Gulf of Mexico and off the southeastern coast of Japan. DOE is working to ensure safe and environmentally prudent gas hydrates development and maintain U.S. leadership in fundamental and applied energy R&D on gas hydrates in natural systems. This work includes enhancing DOE laboratory, university, and industry partnerships that focus on essential assessment of resource concentrations, recovery rates, reservoir behavior, and wellbore stability during methane hydrate production.

DOE will conduct scientific drilling and reservoir response testing of gas hydrate bearing sands within the area of the PBU to confirm the occurrence of gas hydrates in two reservoirs and assess the conditions for testing at the site of a stratigraphic test well. The test well was drilled in late 2018 and instrumented to serve as a monitoring well for the upcoming testing. DOE will conduct the testing in partnership with the U.S. Geological Survey; Japan’s Ministry of Economy, Trade and Industry; the Japan Oil, Gas and Metals National Corporation (JOGMEC); and the project operator ASRC Energy Services (AES), a subsidiary of Arctic Slope Regional Corporation (ASRC). The testing will be conducted through a drilling agreement executed between AES and Hilcorp Alaska (on behalf of the Prudhoe Bay Working Interest Owners) and approved by the Alaska Department of Natural Resources (DNR).

“The success of this test will move us closer to characterizing, evaluating, and confirming the potential for gas hydrates production on the Alaska North Slope, in the Gulf of Mexico, and globally,” said Brad Crabtree, Assistant Secretary for Fossil Energy and Carbon Management. “We look forward to continue working with our partners to conduct world-class gas hydrates research.”

The projects partners will drill three additional wells in 2022—a DOE funded geo-data well and two JOGMEC funded production test wells. The geo-data well will be used to gather extensive sediment samples using pressurized coring, and subsequently will be converted into a second monitoring well.  

The objective of the upcoming drilling and testing activities is to conduct reservoir response field experiments long enough to properly evaluate how gas hydrates release natural gas in response to reservoir depressurization. The site in Alaska provides a unique opportunity to conduct experiments over many months as the established production infrastructure will allow continuous access to the site.

This effort builds upon prior gas hydrate field research, including successful short-duration onshore tests under a collaboration lead by Japan and Canada (2002, 2007, and 2008), offshore tests in Japan conducted by JOGMEC (2013 and 2017), and scientific drilling and testing by DOE and partners in Alaska, (2007 and 2011/2012).

In 2018, the United States and Japan successfully completed the initial drilling of the stratigraphic test well on the Alaska North Slope. Pressurized sidewall cores and other samples were collected to confirm the occurrence of gas hydrates at the selected drill site within the PBU. This work confirmed the occurrence of gas hydrates, identified many technical details of its occurrence and nature, and demonstrated the technical feasibility of producing natural gas from the select hydrate deposits. The scientific results of this project were recently published as a virtual special issue of the journal Energy & Fuels.

The collaborative effort has benefitted from the support of the Alaska DNR to facilitate gas hydrate evaluation in Alaska. Alaska DNR approved the project and issued the decision letter on August 4, 2022.

Visit NETL’s website to read more on the initial test well. For more information about FECM’s research, development, demonstration, and deployment efforts, visit FECM’s website and sign up to receive future FECM news alerts.

Original source can be found here.