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James E. Callahan

Publications and source records attributed to James E. Callahan.

6 recordsLinked to original sources
USGS1984

Map showing geochemistry of stream sediments in the Jerry Peak Wilderness Study Area, Custer County, Idaho

The Jerry Peak Wilderness Study Area is about 25 mi south of Challis in Custer County, central Idaho (fig. 1). The study area contains 46,150 acres of land administered by the by the Bureau of Land Management and 1 sq mi owned by the State of Idaho, a total of 46,790 acres. Most of the study area is readily accessible by roads along tributaries of the East Fork Salmon River, especially Road Creek, Herd Creek, and Lake Creek. The southeastern part of the area can be reached from Road Creek by the road down Peck's Canyon and by roads from Thousand Springs Valley, southeast of the study area. Several access roads to past logging operations extend up Sage Creek and its tributaries in the southeast part of the study area. Access to points within the northern part of the area is facilitated by jeep trails that connect with Road Creek and lake Creek and by improved road that extends northward from Herd Lake. The study area is moderately rugged, with local relief approaching 2,000 ft. Jerry (10,010 ft), the highest point within the area, is a low knoll on a north-trending linear ridge (fig. 1). The ridge has not been glaciated, despite its relatively high altitude. Most of the area is thinly covered by grass and low shrubs; trees, for the most part, are restricted to valley bottoms or to local, small groves on hillslopes.

Idaho↗
USGS1978

Preliminary report on the coal resources of the National Petroleum Reserve in Alaska

NPR-A, located on the Arctic slope of Northern Alaska, is underlain by a thick sequence of sedimentary rocks of Cretaceous age which attain a thickness of as much as 4600 m (15,000 feet). The bulk of the coal resources occurs in rocks of the Nanushuk Group of Early and Late Cretaceous age. The Nanushuk Group is a wedge-shaped unit of marginal marine and nonmarine rocks that is as thick as 3300 m (11,000 feet) just west of NPR-A. Within the reserve, coal occurs primarily in the middle and thicker portions of this clastic wedge and occurs stratigraphically in the upper half of the section. Specific data on individual coal beds or zones are scarce, and estimates of identified coal resources of about 49.5 billion tons represent a sampling of coal resources too small to give a realistic indication of the potential resources for an area so large. Estimates of undiscovered resources suggest hypothetical resources of between 330 billion and 3.3 trillion tons. The wide range in the undiscovered resource estimates reflects the scarcity and ambiguity of the available data but also suggests the presence of a potentially large coal resource.

Open-File Report↗
USGS1967

Geologic reconnaissance of possible powersites at Spur Mountain, Tyee, and Eagle lakes, southeastern Alaska

Spur Mountain, Tyee, and Eagle Lakes fill glacially scoured bedrock basins in the Coast Range of southeastern Alaska. The bedrock consists of granitic intrusive rocks and high rank metamorphic rocks associated with or resulting from emplacement of the Coast Range batholith. Spur Mountain damsite is underlain by granodiorite and diorite. The foundation properties of the bedrock are excellent, but the narrowness of the ridge that forms the right abutment and two prominent joint sets that intersect the abutments at high angles may be serious disadvantages. Two possible tunnel routes extend from the upper and lower ends of the lake to the Hulakon River and Unuk River valleys, respectively. They are approximately the same length and both are underlain by intrusive rocks with similar physical properties. Both routes are geologically satisfactory and the choice of one, will probably depend on other factors. The reservoir is underlain and surrounded by impermeable granodiorite, diorite, or related rocks. The abutments of the Tyee Lake damsite are in massive quartz diorite. The channel section is filled to an undetermined depth with coarse talus which is probably too permeable to grout. If the talus deposit is too deep to be removed economically, it might be possible to develop the site by drawing the lake down. The tunnel and penstock route is underlain by granodiorite, composite gneiss, hornblendite, and quartz diorite which are impermeable except possibly along two zones of close-spaced or open joints. The powerhouse site on Bradfield Canal is underlain by quartz diorite similar to the bedrock at damsite. The Eagle Lake powersite includes two possible damsites. The Eagle Lake damsize at the outlet of Eagle Lake is underlain by composite gneiss consisting of foliated biotite gneiss interlayered with banded quartz diorite, which is largely concealed with thin deposits of soil and colluvium. The foliation strikes normal to the alignment of the dam, and minor leakage along foliation planes might be expected. The possibility of a deep buried channel or solution cavities in marble underlying the stream bed should be considered. The other damsite is located at the outlet of Little Eagle Lake about 2 1/2 miles below the Eagle Lake damsite. The drainage area and storage capacity above the Little Eagle Lake site would be about 70 percent greater than for the Eagle Lake damsite, but the dam would have to be three to four times larger than the one at Eagle Lake to reach the same water level. This dam may be economically feasible due to large volumes of impervious fill material available for construction of an earthfill dam near Little Eagle Lake. Four saddles, which are probably abandoned stream channels, are in a low divide at the head of Eagle Lake. The depth and permeability of fill in the saddles are unknown factors which should be investigated. The tunnel route extends from the headward part of Eagle River to the head of Bell Arm and is underlain by poorly foliated gneissic quart diorite.

Alaska↗