Brookian Sequence Well Log Correlation Sections and Occurrence of Gas Hydrates, North-Central North Slope, Alaska
USGS Publishes Alaska North Slope Gas Hydrate Well Data Analysis and Stratigraphic Framework
Lewis, K.A., and Collett, T.S., 2013, Brookian sequence well log correlation sections and occurrence of gas hydrates, north-central North Slope, Alaska: U.S. Geological Survey Scientific Investigations Report 2013–5050, 23 p., http://pubs.usgs.gov/sir/2013/5050/.
Gas hydrate research has a long history in northern Alaska. This research includes the drilling, coring, and well log evaluation of several gas hydrate test wells and two resource assessments of gas hydrates on the Alaska North Slope. Building upon these previous investigations, this report provides a summary of the pertinent well log, gas hydrate, and stratigraphic data for key industry and research wells related to gas hydrate occurrence in the north-central portion of the Alaska North Slope. The primary purpose of this report is to provide an overview of the gas hydrate research that has been conducted by the USGS Energy Resources Program on the North Slope of Alaska. It combines, for the first time, the results of previously published studies, unpublished stratigraphic data from well log analyses, and the results of more recent investigations.
This report presents the stratigraphic framework developed by the USGS for investigating gas hydrates in the greater Prudhoe Bay area, as illustrated on nine regional well log correlation sections (see included map and sample well log cross section). The report also includes a tabulated summary of pertinent well data (such as available well logs, key well log markers, tops and bases of gas hydrate-bearing intervals, and the hydrate stability zone) for each of the 122 wells used in the construction of the included cross sections. In addition, descriptions of the principal stratigraphic units associated with gas hydrate accumulations, general properties of gas hydrates, controls on gas hydrate formation, and the relation between permafrost and gas hydrate accumulations are reviewed in this report.
This report provides an up-to-date compilation and analysis of the well log inferred gas hydrate occurrences on the Alaska North Slope and documents more than 30 years of USGS gas hydrate research efforts in Alaska. This foundational data set will continue to guide and grow with gas hydrate research activities in Alaska.
Map of central North Slope showing study wells, producing oil fields, known gas hydrate accumulations, free gas accumulations, and lines of well log correlation sections (red solid lines) included within this report. (Download Document)
Well Log Section:
Sample well log correlation section showing well log markers, gas hydrate picks, gas hydrate stability zone, base of ice-bearing permafrost, and depth of permafrost (0°C) where available. (Download Document)