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Methane hydrate test program progresses
DOG approves construction of temporary ice pad to extend Prudhoe Bay gravel pad to support drilling project; new drilling is underway
Alan Bailey for Petroleum News
Alaska’s Division of Oil and Gas has approved a change to the plan of operations for methane hydrate production testing on the North Slope. The change involves the construction of an ice pad to temporarily expand the area of the Prudhoe Bay Unit 7-11-12 gravel pad that is being used for the testing. ASRC Consulting and Environmental Services had told the division that the ice pad would be a staging area for modules being used in the project - the modules will be placed on and removed from the pad using a crane, thus eliminating any need for tractor or trailer equipment on the ice.
Meanwhile, according to data from the Alaska Oil and Gas Conservation Commission, one of three new wells planned for the project was completed in November.
International team ASRC Energy Services is the project operator as part of an international team, in which the U.S. Department of Energy is partnering with the U.S. Geological Survey; Japan’s Ministry of Economy, Trade and Industry; and the Japan Oil, Gas and Metals National Corp. The testing is being conducted through an agreement between ASRC Energy Services and Hilcorp Alaska, the Prudhoe Bay unit operator.
The project has an objective of testing the practicality of sustained natural gas production from subsurface methane hydrate deposits. Methane hydrate is a solid in which molecules of methane, the primary component of natural gas, are concentrated inside a lattice of water molecules. Vast quantities of the material are known to exist around the base of the permafrost under the North Slope.
The North Slope, being an onshore region with a substantial oil and gas infrastructure, is considered an excellent location for testing the production of gas from methane hydrate. Although short-term production has previously been demonstrated, the feasibility of sustained, long-term production has yet to be determined. Nor are the economics of potential commercial production fully understood.
Planned wells The research team completed an initial test well from the Prudhoe Bay pad in January 2019. The well penetrated two highly saturated hydrate-bearing reservoirs. A plan to drill additional wells was delayed, presumably because of the COVID pandemic. The U.S. Department of Energy has said that the plan is now to drill two further production test wells and a geo-data well. The geo-data well will be used to collect subsurface sediment samples before being converted into a monitoring well. The well drilled in 2019 will also be used for collecting data associated with the test program.
It is not clear from available data which of the new wells was completed in November.
DOE has said that the objective of the testing is to determine the response to production of a hydrate reservoir over a long enough time period to effectively evaluate how gas hydrates release gas in response to reservoir depressurization.
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