Summary: | In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), Inc., and the U.S.
Geological Survey conducted an extensive data collection effort at the "Mount Elbert #1" gas
hydrates stratigraphic test well on the Alaska North Slope (ANS). The 22-day field program
acquired significant gas hydrate-bearing reservoir data, including a full suite of open-hole well
logs, over 500 feet of continuous core, and open-hole formation pressure response tests. Hole
conditions, and therefore log data quality, were excellent due largely to the use of chilled oilbased
drilling fluids. The logging program confirmed the existence of approximately 30 m of gashydrate
saturated, fine-grained sand reservoir. Gas hydrate saturations were observed to range
from 60% to 75% largely as a function of reservoir quality. Continuous wire-line coring operations (the first conducted on the ANS) achieved 85% recovery through 153 meters of
section, providing more than 250 subsamples for analysis. The "Mount Elbert" data collection
program culminated with open-hole tests of reservoir flow and pressure responses, as well as gas
and water sample collection, using Schlumberger's Modular Formation Dynamics Tester (MDT)
wireline tool. Four such tests, ranging from six to twelve hours duration, were conducted. This
field program demonstrated the ability to safely and efficiently conduct a research-level openhole
data acquisition program in shallow, sub-permafrost sediments. The program also
demonstrated the soundness of the program's pre-drill gas hydrate characterization methods and
increased confidence in gas hydrate resource assessment methodologies for the ANS.
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