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Gravity data were acquired at 1,175 stations during the period April 13 to May 3, 1982 by EDCON, Inc. using a helicopter-borne inertial surveying system and LaCoste and Romberg G-meters. Of the total number of stations, 1,156 were acquired along one of 19 lines and the remaining 19 stations were control points or gravity bases. The survey is located in southwestern Alaska approximately 325 kilometers west of Anchorage, Alaska. Stations acquired along the 19 lines. In general, gravity stations were spaced approximately 1,600 meters apart along northwest-southeast oriented lines which were spaced 9,500 meters apart. [ABSTRACT FROM AUTHOR]

The article discusses research which investigated carbonaceous mudstones and coals collected from McGrath Quadrangle in Alaska. Topics explored include the geologic features of the McGrath Quadrangle, the techniques utilized to evaluate generative potential and thermal maturity of rock samples such as Rock-Eval pyrolysis and visual kerogen analysis, and the measurement of organic carbon and hydrogen content in addition to the vitrinite reflectance values of the samples studied.

A physiographically prominent, approximately 40 km2 plateau lies roughly 20 km east of Mount Spurr volcano, northwestern Cook Inlet region, Alaska, and comprises the preserved remnant of a volcaniclastic succession, designated in this study as map unit Qvc. Although this readily mappable package of volcaniclastic rocks has been recognized in numerous studies during the past five decades, uncertainties regarding its age and origin have persisted. Qvc generally consists of structureless, thick-bedded, moderately indurated, subhorizontally dipping, matrix- to clastsupported granule--boulder conglomerate, gravelly sandstone, and gravelly mudstone. Clasts and matrix are chiefly dense to vesicular intermediate(?) lava fragments and pumiceous to scoriaceous pyroclasts. The unit is thickest to the north, where an approximately 275-m-thick section discontinuously crops out south of Capps Glacier. Field relations and the mapped surface trace of a sub-Qvc angular unconformity suggest that marked topographic relief on a paleosurface--eroded into underlying Paleogene and Neogene-age strata--was established prior to deposition of the volcaniclastic succession. Several exposures of chaotically folded Qvc strata are associated with clastic dikes; these features are interpreted to record soft sediment deformation resulting from fluidization and/or liquefaction of watersaturated sandy deposits in an environment subject to earthquake-induced shaking, high instantaneous sedimentation rates, or a combination thereof. U--Pb detrital zircon geochronology maximum depositional age determinations indicate the youngest sampled strata are unlikely to be older than 0.40 ± 0.09 Ma, but may be as young as or younger than 0.31 ± 0.14 Ma; the oldest sampled strata are unlikely to be older than 1.0 Ma, but may be no older than 0.48 ± 0.05 Ma. This study's most statistically robust, precise, and conservative maximum depositional age is 0.45 ± 0.06 Ma, incorporating the youngest grain ages from all sampled strata that overlap at 2-sigma (n = 19). Moraines correlated to the Marine Isotope Stage (MIS) 4 penultimate glaciation interval locally onlap the eroded plateau, providing a minimum age of ~75 ka for the unit. In conjunction, these new age constraints chiefly limit Qvc sedimentation to middle and late Pleistocene time but prior to MIS 4, a considerable improvement over previous age estimates that ranged widely from Miocene through Holocene. We interpret Qvc to be a valley-fill succession that records sedimentation from volcanogenic debris flows and hyperconcentrated flows (lahars) at a low-gradient alluvial fan or floodplain depositional site. Texturally and compositionally similar laharic strata are reported elsewhere within several tens of kilometers of continental arc volcanoes, consistent with the plateau's proximity to the modern volcanic arc of upper Cook Inlet. This lahar-prone, volcanoproximal depositional system was evidently subsequently dismantled by extensive erosion during and/or after MIS 4. The remaining volcaniclastic deposits persist in exposures along the margins of the plateau, with no recognized proximal or distal equivalents at this time; however, we propose that the source of volcaniclastic detritus for this unit was an arc volcano--possibly ancestral Mount Spurr--toward the west. [ABSTRACT FROM AUTHOR]

The article presents a report on the petrographic and routine core-analysis data and provides preliminary interpretations on them. Two hundred seventeen model analyses and 188 routine core analyses were conducted on Tertiary and Mesozoic siltstones and sandstones gathered during the 2007-2010 field seasons from 6 geographic areas in upper and lower Cook Inlet, Alaska. It indicates that the observations are based on a limited number of outcrop samples gathered from a widely dispersed localities.

The article presents a summary of the reconnaissance field data collected in the Susitna basin in during a reconnaissance field study of the Susitna Basin, Alaska conducted in late June 2011. The reconnaissance aims to gather new information for understanding the basin formation history and stratigraphy. The collaborative reconnaissance filed studies of the Susitna basin provided new outcrop-based stratigraphic data of Cenozoic basin-fill deposits within and along the margin of Susitna basin.

This publication discusses fossil fuel and geothermal energy resource in the Lower Yukon-Kuskokwim Region in Alaska. Topics covered include the energy supply to support Alaska's economy and the geography of the Lower Yukon-Kuskokwim Region. An overview of mineable coal resource potential, the conventional oil and gas resources, and the unconventional resources comprising coalbed methane, gas hydrates and shale gas is also provided.

The article discusses the potential of locally exploitable fossil fuel and geothermal energy resources in the Yukon-Koyukuk/Upper Tanana Energy Region which is recognized by the Alaska Energy Authority (AEA) in their Energy Plan. It describes the geographic and geologic setting of the region. It also outlines the mineable coal resource potential and conventional oil and gas resource potential in the region.

Economic growth and stability in Alaska hinges partially, if not primarily, on the availability of a mix of affordable and sustainable energy sources. The high and volatile prices of diesel fuel and heating oil have created economic hardship in many areas of Alaska, particularly remote rural communities where these imported fuels are the primary source of energy. Developing local energy sources that are not tied to a global market will help diversify the state's energy portfolio and help facilitate economic growth in many regions. Unfortunately, all areas are not created equal in energy accessibility. The purpose of this report is to summarize existing information concerning locally available, geologically hosted sources of energy across the state. This work considers both geothermal and fossil fuel (oil, natural gas, and coal) resources and is intended to supplement the Alaska Energy Authority's ongoing analysis of non-geologic energy sources such as hydro, wind, and biomass. Collectively, these summaries provide a basis for ensuring that Alaska's entire suite of potential energy sources is considered. Although this review does not represent a comprehensive analysis or resource assessment, the information should assist local, regional, and statewide efforts to reduce the dependence on diesel for heat and electricity. The potential for locally exploitable natural resources varies widely across the state, and certain regions possess more favorable geologic attributes than others. The chapters of this report are subdivided into the 11 regions recognized by the Alaska Energy Authority (AEA, 2009). For each region, discussion is provided on its potential for geologically hosted energy resources including coal, conventional and unconventional oil and gas, and geothermal resources. Many areas of the state lack sufficient geologic information to reliably evaluate local energy potential; summaries of each region conclude with recommendations regarding what additional data or strategies would be most helpful in developing new energy resources for local or regional use. [ABSTRACT FROM AUTHOR]

An outcrop along the west side of the Ivishak River, North Slope, Alaska, provides a rare view of a sandstone-rich succession overlying an incision surface in the Canning Formation. The outcrop is characterized by a series of complex folds cut by several faults. Nearby seismic, well, and outcrop control suggest the succession is Campanian. The incision surface is exposed on a flat-lying to gently north-dipping anticlinal limb, where it truncates bedding in underlying mudstones at a relatively low angle. Two facies associations are recognized: 1.) a slope-basin-floor (SBF) association consisting of mudstone and minor thinly interbedded coarse siltstone and very fine sandstone, and 2.) an incision-fill (IF) association consisting of abundant beds a few centimeters to 40 cm thick of upper very fine to lower fine sandstone, separated by thin interbeds of mudstone and siltstone. The IF association is subdivided into two sub-associations--a lower IF and an upper IF--the difference between these subdivisions is a slightly higher net-to-gross in the upper division. The lower IF association is truncated by an intra-incision(?) surface that is overlain by mudstones resembling the SBF association. Bioturbation appears absent in both associations. Due to the limited outcrop extent, the upper IF subdivision is not known with certainty to be part of the incision-fill. Both associations (SBF and IF) are interpreted to record deposition in a lower slope to proximal basin-floor setting. The SBF association records deposition from turbid suspensions and very dilute, lowvolume turbidity currents in an unconfined setting. The IF association records deposition from decelerating, confined turbidity currents and some concentrated density flows (terminology of Mulder and Alexander, 2001). The basal incision is interpreted to record a mass-wasting event triggered during relative sea level fall. The basal incision and intra-incision(?) truncation surfaces represent potential bypass surfaces across which significant volumes of sand could have been transported seaward to accumulate in a slope apron or basin-floor fan system. It seems probable that similar incisions are common in slope deposits of the Canning Formation, with similar implications. Sandstone composition and reservoir quality are addressed in a companion report by Helmold. [ABSTRACT FROM AUTHOR]