Scientific Results of the Hydrate-01 Stratigraphic Test Well Program, Western Prudhoe Bay Unit, Alaska North Slope

The United States Department of Energy, the MH21-S Research Consortium Japan, and Geological Survey are collaborating to enable gas hydrate scientific drilling extended-duration reservoir response testing on Alaska North Slope. To feasibly execute such a test, location is required that accessible from existing roads gravel pads can be occupied without disrupting ongoing industry operations. A review potential locations meeting these criteria determined likely occurrence in two fine-grained marginal-marine sands Tertiary age vicinity inactive “Kuparuk State 7-11-12” exploration pad western Prudhoe Bay Unit (PBU). Existing well seismic data for site were insufficient preclude free within deeper (and most prospective) target sand. Therefore, with support PBU Working Interest Owners, Natural Resources, Petrotechnical Resources Alaska, Hydrate-01 Stratigraphic Test Well (STW) was drilled December 2018 confirm suitability future testing. successfully ?3290 ft (1003 m) subsea vertical depth at bottom hole approximately 900 (?275 east surface location. program featured acquisition full suite logging while data, collection side-wall pressure cores, installation distributed temperature acoustic sensor fiber-optic cables. log acquired confirmed high saturation sands. Integrated evaluation sidewall core provide petrophysical geomechanical property information allow depressurization simulated. “B1 sand” deemed favorable as result sediments intrinsic permeability, 100 (30 base stability, minimal risk direct communication permeable water-bearing (hydrate-free) zones. shallower “D1 provides secondary differentiated by colder situ temperatures interpreted hydraulic lower section non-hydrate-bearing, water-saturated also least one sub-seismic fault close proximity B1 sand reservoir. better image distribution gas-hydrate-bearing sections associated faults, three-dimensional (3D) profile conducted early 2019 using sensors installed part STW completion. Detailed two-dimensional (2D) 3D geologic models have been constructed numerical simulations inform planning tests site.