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We have updated a simple polyvinyl chloride plastic canister design by adding internal headspace temperature measurement, and redesigned it so it is made with mostly offthe-shelf components for ease of construction. Using self-closing quick connects, this basic canister is mated to a zero-head manometer to make a simple coalbed methane desorption system that is easily transported in small aircraft to remote localities. This equipment is used to gather timed measurements of pressure, volume and temperature data that are corrected to standard pressure and temperature (STP) and graphically analyzed using an Excel based spreadsheet. Used together these elements form an effective, practical canister desorption method. Introduction: This paper presents a system for coal core and drill cuttings desorption that is simplified from existing custom made designs (McLennan et al., 1995; Mavor and Nelson, 1997). This system emphasizes simpler desorption canisters and manometers constructed with off-the-shelf materials and parts. This construction is used because our field areas are usually in remote, sparsely developed areas, our concept is to keep the method and equipment as simple yet light as practical and still have robust equipment that can stand up to unattended air or road transport to remote localities. Further, because the equipment is adapted from widely available, off the shelf equipment, it has proven possible to buy materials and construct canisters in rural locations. Our system, with 10 to 20 three-inch canisters to desorb and sample gases, can fit in three 20 to 40 gallon plastic household storage containers. At the well site, the storage containers also serve as tanks for the constant temperature baths. Construction of Basic Desorption Equipment: Canisters The canister body is made from polyvinyl chloride (PVC) plastic pipe and fittings that are all commercially available schedule 40 grade materials (Appendix 1). The canister body diameter is determined by two factors, the core diameter, and the need to fit the core piece length and diameter as closely as possible to minimize headspace. For core diameters in the 2 to 2.75 inch range, we use 3 inch internal diameter schedule 40 PVC pipe. For cores in the 3 to 3.75 in range, we use 4 inch internal diameter schedule 40 PVC pipe. We cut this material in a 14 inch length (Figure 1) for a 12 inch core piece. The extra two inches are to allow one inch for pressure plug insertion and one inch for the inefficient packing of inadvertently broken core pieces. We find that the 14 inch length and 3-and 4 inch pipe diameters cover the common range of coal core pieces available to us. While intermediate PVC pipe diameters may fit core diameters more closely, the pipe fittings for these sizes can be harder to find and even less commonly found in rural field areas. Other sizes are possible based on a scaled version of our design, but we have found that the three and four inch pipe diameters fit most of the common core sizes used on exploration wells. Core pieces of less than ...

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Idaho's Snake River Plain is underlain by a young sequence of basaltic lava fl ows that house one of the most conductive aquifers in the world and have been sculpted by at least three megafl oods in the last ~100 k.y. The timing and routing of these fl oods, and their interaction with the underlying aquifer, have taken on renewed signifi cance because they have carved amphitheater-headed dry canyons analogous to those found on Mars. In this study, we use cosmogenic 3 He and 21 Ne dating of fl ood-deposited boulders to show that the Big Lost River and Bonne ville fl oods were closely spaced in time at ca. 22.3 and ca. 17.5 ka, respectively. Most of the dry canyons record signifi cant erosion during the Big Lost River fl ood, despite its much smaller magnitude than the later Bonne ville fl ood. We explain this puzzling observation by proposing a composite erosion model in which erosion during the Big Lost River fl ood was partially accomplished by routing of fl oodwaters through the Snake River Plain aquifer. Topographic analysis shows that Big Lost River fl oodwaters ponded in the Terreton Basin, infi ltrated into the aquifer, and likely emerged as return fl ow in watersheds upstream of the dry canyons. We propose that sustained and focused erosion associated with return fl ow over months to years could explain the unique morphology of some dry canyons. Such a model also explains why most dry canyons are coincident with springs and surface watersheds, and it may provide a model for the way in which morphologically similar canyons evolved on Mars.

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit http://store.usgs.gov Suggested citation: Clark, A.C., 2014, Coalbed natural gas exploration, drilling activities, and geologic test results, 2007-2010, Wainwright, Alaska: U.S. Geological Survey Open-File Report 2014-1004, 65 p., http://dx.doi.org/10.3133/ofr20141004. ISSN 2331ISSN -1258 Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. AbstractThe U.S. Geological Survey, in partnership with the U.S. Bureau of Land Management, the North Slope Borough, and the Arctic Slope Regional Corporation conducted a four-year study designed to identify, define, and delineate a shallow coalbed natural gas (CBNG) resource with the potential to provide locally produced, affordable power to the community of Wainwright, Alaska. From 2007 through 2010, drilling and testing activities conducted at three sites in or near Wainwright, identified and evaluated an approximately 7.5-ft-thick, laterally continuous coalbed that contained significant quantities of CBNG. This coalbed, subsequently named the Wainwright coalbed, was penetrated at depths ranging from 1,167 ft to 1,300 ft below land surface. Core samples were collected from the Wainwright coalbed at all three drill locations and desorbed-gas measurements were taken from seventeen 1-ft-thick sections of the core. These measurements indicate that the Wainwright coalbed contains enough CBNG to serve as a long-term energy supply for the community.Although attempts to produce viable quantities of CBNG from the Wainwright coalbed proved unsuccessful, it seems likely that with proper well-field design and by utilizing currently available drilling and reservoir stimulation techniques, this CBNG resource could be developed as a long-term economically viable energy source for Wainwright.