Analysis of Modular Dynamic Formation Test Results from the Mount Elbert-01 Stratigraphic Test Well, Milne Point Unit, North Slope Alaska

BRIAN J. ANDERSON, JOSEPH W. WILDER, MASANORI KURIHARA, MARK D. WHITE, GEORGE J. MORIDIS, SCOTT J. WILSON, MEHRAN POOLADI-DARVISH, YOSHIHIRO MASUDA, TIMOTHY S. COLLETT, ROBERT B. HUNTER, HIDEO NARITA, KELLY ROSE, RAY BOSWELL

Copyright 2008, International Conference on Gas Hydrates (ICGH 2008).

Proceedings of the 6th International Conference on Gas Hydrates (ICGH 2008), Vancouver, British Columbia, CANADA, July 6-10, 2008.

In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), and the U.S. Geological Survey, collected the first open-hole formation pressure response data in a gas hydrate reservoir (the “Mount Elbert” stratigraphic test well) using Schlumberger’s Modular Dynamics Formation Tester (MDT) wireline tool. As part of an ongoing effort to compare the world’s leading gas hydrate reservoir simulators, an international group conducted history matches of one 12-hour test that included an initial stage of pressure drawdown and response in which pressures were maintained above the level where gas hydrate dissociation would occur; a second stage with 15 min of flow and 97 min buildup that included gas hydrate dissociation and gas production; and a third stage of 116 min of flow and 266 min of buildup. The test also included temperature measurements taken by a device attached to the MDT’s intake screen. History matches of these test data were accomplished using five different reservoir simulators: CMG STARS, HydrateResSim, MH-21 HYDRES, STOMP-HYD, and TOUGH+HYDRATE. Simulations utilized detailed information collected across the reservoir either obtained or determined from geophysical well logs, including thickness (37 ft.), porosity (35%), hydrate saturation (65%), intrinsic permeability (1000 mD), pore water salinity (5 ppt), and formation temperature (3.3 – 3.9 degrees C). This paper will present the approach and preliminary results of the history matching efforts, including estimates of initial formation permeability and analyses of the various unique features exhibited by the MDT results.