• Determination of methane hydrate stability zones in the Prudhoe Bay, Kuparuk River, and Milne Point units on the North Slope of Alaska

      Westervelt, Jason V. (2004-05)
      Estimates range from approximately 37 to 44 trillion cubic feet of in-place gas in methane hydrate from within the Eileen Trend of the Prudhoe Bay (PBU), Kuparuk River (KRU), and Milne Point (MPU) Units on the North Slope of Alaska (Collett, 1993). This study was based on measuring pressure and temperature conditions for hydrate dissociation. The results showed that the depth of the hydrate stability zone (HSZ) ranges from 585 to 780 meters. The results from this study also show that the HSZ in the Alaska North Slope (ANS) is thinning westward. This study also showed that the effect of formation brines typically found on the North Slope only affects the depth of the hydrate stability zone by 30 to 45 meters when a porous media is not present. Experiments carried out on a porous media sample provided by the Anadarko Corporation showed that the formation brines only affect the depth of the hydrate stability zone by 10 to 15 meters. Geothermal gradients, gas composition, and the type of porous media play the biggest role in the thickness of the HSZ. These variables are also the most important when determining the depth to the HSZ.