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USGS1974

Geological Survey published reports on Alaska, 1940-1959, indexed by quadrangle

Geological Survey reports published as Professional Papers, Bulletins, Water Supply Papers, and Circulars are listed by the quadrangles (scale 1:250,000) into which Alaska has been divided for topographic mapping (p. 2). This index does not include reports that deal only with administrative matters or that were placed in open files but not formally published. Reports that deal with Alaska as a whole, with areas that cannot be identified with any specific quadrangle, or with offshore areas that are not within quadrangle boundaries, or that consist mainly of statistical data on the quality or quantity of water are listed under ALASKA - GENERAL, as are bibliographies, indexes, and similar publications. The ALASKA - GENERAL list appears before the alphabetically arranged quadrangle listings.

Alaska↗

USGS1976

Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Chandalar and Wiseman quadrangles, Alaska

These summaries of references are designed to aid in library research on metallic and nonmetallic (other than mineral fuels and construction materials) mineral occurrences in the Chandalar and Wiseman quadrangles in the southern Brooks Range, Alaska. All references to reports of the Geological Survey, to most reports of the U.S. Bureau of Mines, and to most published reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies released before January 1, 1975, are summarized. An unpublished manuscript report of the Alaska Territorial Department of Mines (Reed, 1938) is included; references to it are summarized in greater detail than those to the kinds of reports listed above. Certain, mainly statistical, reports such as the annual Minerals Yearbook of the U.S. Bureau of Mines and the biennial and annual reports of the State of Alaska Division of Geological and Geophysical Surveys and its predecessor State and Territorial agencies are not included. This report is divided into three parts: a section made up of summaries of references arranged alphabetically first by quadrangle and second by occurrence name; a section that lists synonyms for names in the first section, claim names, and the names of operators and owners of mines and prospects; and a section that lists, by author, all references summarized in the first section.

Alaska↗

USGS1976

Preliminary space image lineament maps of Alaska

Examination of images from Nimbus, NOAA and Landsat satellites has revealed a series of lineaments in the earth's surface in Alaska 1000 km or more in length (fig. 1). These lineaments occur as alinements of surface geologic structures, linear valleys or ridges, and linear changes in tonal contrast marking differences in soil type, soil moisture, or vegetation. The lineaments are believed to represent the surface traces of zones of weakness deep within the earth's crust along which vertical or horizontal adjustments to earth stresses persistently recurred since at least Precambrian time. A consistent pattern in the lineaments can be discerned in Alaska (fig. 1D), and throughout the North American Cordillera (fig. 2). This pattern is believed to represent a mosaic of crustal blocks, whose differential movements have guided the tectonic development of the Cordillera. Areas in which mineral deposits are known to be concentrated are alined along many of the lineaments or occur at lineament intersections, suggesting that the zones of weakness reflected by the lineaments provided felicitous pathways for upward movement of mineralizing agents. Other lineaments bound areas of high mineral concentration suggesting that some crustal blocks have had a tectonic history more favorable for mineralization than others. These conclusions suggest that the study of space image lineaments can provide new and fruitful approaches to the search for concealed mineral deposits. In Alaska, some lineaments coincide in part with active fault traces and some separate areas of significantly different structure and geologic history. However, the movements along the zones of weakness which these lineaments are believed to reflect have been too slow and spread over too many millions of years for the lineaments to be considered as marking zones of present earthquake hazard. Detailed discussion of the lineaments, and of interpretations as to their meaning, are contained in: 1) a paper presented by Lathram and Raynolds at the First William T. Pecora Memorial Symposium, Sioux Falls, South Dakota, October 28-31, 1975, and 2) Lathram and Albert, 1976, Significance of space image linears in Alaska, in Hodgson, R.A., Gay, S.P., and Benjamins, J.Y., eds., Proceedings of the First International Conference on the New Basement Tectonics: Utah Geol. Assoc. Pub. 5, p. 11-26.

Alaska↗

USGS1977

Preliminary foraminiferal biostratigraphy and correlation of selected stratigraphic sections and wells in the Gulf of Alaska Tertiary province

As part of ongoing research by the U.S. Geological Survey on the geology and resource potential of the Gulf of Alaska Tertiary Province, a vast amount of data has been accumulated over the past 25 years on the lithology and paleontology of bedded rocks in the province. This report brings together available information on the occurrence, age, and paleoecologic, significance of benthonic foraminifers and presents correlations based on these data from 16 measured stratigraphic sections and 12 exploratory wells. Relatively few reports employing modern taxonomic methods developed during the past 40 years have been published on foraminiferal biostratigraphy of the Gulf of Alaska. Reports by Cushman (1941), Cushman and Todd (1947), Tappan (1951), Todd (1953), Loeblich and Tappan (1953), Todd (1957), Rau (1963), Cooper (1964), and Todd and Low (1967) are primarily concerned with taxonomy, ecology and paleoecology, or the geologic age of assemblages from isolated outcrops. Almost no data have been published on foraminiferal correlations of measured sections and wells. The paucity of such information has prompted the synthesis and interpretation of foraminiferal data that provide the framework of correlation presented in this report. Some of the benthonic provincial stages that have been assigned to lower and middle parts of the Tertiary of other west coast areas are recognized for the Gulf of Alaska. Divisions for the upper part of the Tertiary are broad, but specific faunal occurrences are recognized as possible aids to correlations. Regional correlations presented in this report are necessarily broad and may be modified and redefined when new data become available from the current round of exploratory drilling for petroleum in the offshore part of the Gulf of Alaska Tertiary Province. It is anticipated that this report will be of particular interest to readers associated with petroleum exploration. As a convenience to them and because most foraminiferal data from wells, including those of this report, are from cuttings, all checklists are arranged to show plainly the highest occurrence of each species within each measured section and well. Furthermore, in conformity with these data, all sections and wells are described from the top to bottom. The text describes the stratigraphic and paleoecologic significance of foraminifers by biostratigraphic units and by individual sections and wells.

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USGS1979

Outer continental shelf oil and gas information program; Alaska index (December 1974 - June 1979)

As part of a national goal to reduce dependence on foreign energy sources, the United States is currently managing a program for leasing of OCS oil and gas resources. The areas potentially affected, consisting of 22 coastal states and Pennsylvania, can be grouped into four major areas: Alaska, Atlantic, Gulf of Mexico and Pacific. The Alaska Area has three lease sale areas: Gulf of Alaska, the Bering Sea and the Chukchi and the Beaufort Sea (see Figures I and 2). Most of the information used by both the government and industry on the hydrocarbon potential of the Alaska Area is initially acquired and compiled on a regional basis. These data are used by industry in nominating tracts for lease and in preparation of bids and by the Department of the Interior for general sale area identification, tract selection, environmental impact statements and resource evaluation. Subsequent environmental information and data analysis is directed toward defining specific sub-areas and site-specific evaluation.

Alaska↗

USGS1979

Resource report for proposed OCS lease sale no. 70, St. George Basin, shelf area, Alaska

St. George basin is a long (300 km), narrow (30-50 km) graben whose long axis strikes northwestward, parallel to the continental margin of the southern Bering Sea. Located near the Pribilof Islands, and beneath the virtually featureless Bering Sea shelf, the basin is filled with more than 10 km of sedimentary deposits. These sedimentary rocks are ruptured by normal faults associated with the sides of the graben; these ruptures commonly correlate with offsets in the basement surface. Offset along these faults increases with depth implying that they are growth-type structures. Basement rocks, that floor and flank St. George basin are part of an assemblage of Mesozoic eugeosynclinal rocks that extends from southern Alaska to eastern Siberia beneath the Bering Sea margin and outer shelf. A parallel belt of igneous rocks of late Mesozoic and earliest Tertiary age may also extend from western Alaska to northeastern Siberia beneath the inner Bering Sea shelf. The Bering Sea margin and adjacent shelf were apparently uplifted by the end of Mesozoic time, resulting in deep subaerial erosion• Following uplift, the outer Bering Sea shelf has undergone extensional rifting and regional subsidence. Differential subsidence has resulted in the formation of a series of basement ridges and basins whose axes parallel the Bering Sea margin. Some of these basins are very large to gigantic in size, e.g., St. George basin, and involve crustal subsidence exceeding 10 km. Such large scale crustal collapse suggests deep crustal or upper mantle processes, such as thermal metamorphism or stress-induced crustal migration. Nine wells drilled along the northern coast of the Alaska Peninsula, as well as several onshore Soviet wells in northeastern Siberia, relate directly to the submerged basins of the Bering Sea shelf. Although all of the wells on the Alaska Peninsula were abandoned as dry holes, shows of oil and gas were found. In addition, Soviet drilling resulted in the discovery of oil and gas shows in Oligocene and Miocene sandstone. Regional geologic and geophysical mapping suggests that there are suitable source beds, reservoir rocks, and traps within St. George basin. However, it is not known if hydrocarbons are present or if the possible reservoirs are of commercial size. A resource appraisal of St. George basin out to 200 meters water depth indicates that, at 5 percent probability, 6.4 billion barrels of oil and 18.6 trillion cubic feet of gas may be in the basin; at 95 percent probability 0.8 billion barrels of oil and 4.5 trillion cubic feet of gas may be in the basin. The statistical mean of the appraisal is 2.7 billion barrels of oil and 10.3 trillion cubic feet of gas. A large number of faults, evidence for recent movement along some of the faults, and high seismicity all indicate that faulting is a major environmental concern for the outer continental shelf region of the southern Bering Sea, especially in St. George basin. Most of the faults are potentially active and their movement is probably influenced by the local geology, including basement structures and sediment loading. Unstable sediment masses pose potential threats to resource development in the vicinity of the Pribilof Canyon. Volcanic activity along the Aleutian arc south of St. George basin may also pose an environmental hazard to petroleum development in the area. Another environmental hazard is the presence of shallow gas pockets, which could pose such problems during drilling as blowouts and liquefaction of bottom sediment.

Alaska↗

USGS1979

Geology and physiography of the continental margin north of Alaska and implications for the origin of the Canada Basin

The continental margin north of Alaska is of Atlantic type. It began to form probably in Early Jurassic time but possibly in middle Early Cretaceous time, when the oceanic Canada Basin of the Arctic Ocean is thought to have opened by rifting about a pole of rotation near the Mackenzie Delta. Offsets of the rift along two fracture zones are thought to have divided the Alaskan margin into three sectors of contrasting structure and stratigraphy. In the Barter Island sector on the east and the Chukchi sector on the west the rift was closer to the present northern Alaska mainland than in the Barrow sector, which lies between them. In the Barter Island and Chukchi sectors the continental shelf is underlain by prisms of clastic sedimentary rocks that are inferred to include thick sections of Jurassic and Neocomian (lower Lower Cretaceous) strata of southern provenance. In the intervening Barrow sector the shelf is underlain by relatively thin sections of Jurassic and Neocomian strata derived from northern sources that now lie beneath the outer continental shelf. The rifted continental margin is overlain by a prograded prism of Albian (upper Lower Cretaceous) to Tertiary clastic sedimentary rocks that comprises the continental terrace of the western Beaufort and northern Chukchi Seas. On the south the prism is bounded by Barrow arch, which is a hingeline between the northward-tilted basement surface beneath the continental shelf of the western Beaufort Sea and the southward-tilted Arctic Platform of northern Alaska. The Arctic platform is overlain by shelf clastic and carbonate strata of Mississippian to Cretaceous age, and by Jurassic and Cretaceous clastic strata of the Colville foredeep. Both the Arctic platform and Colville foredeep sequences extend from northern Alaska beneath the northern Chukchi Sea. At Herald fault zone in the central Chukchi Sea they are overthrust by more strongly deformed Cretaceous to Paleozoic sedimentary rocks of Herald arch, which trends northwest from Cape Lisburne. Hope basin, an extensional intracontinental sedimentary basin of Tertiary age, underlies the Chukchi Sea south of Herald arch.

Open-File Report↗

USGS1979

Interim report on the St. Elias, Alaska earthquake of 28 February 1979

On 28 February 1979 an earthquake with surface wave magnitude (Ms) of 7.7 (W. Person, personal communication, 1979) occurred beneath the Chugach and St. Elias mountains of southern Alaska (fig. 1). This is a region of complex tectonics resulting from northwestward convergence between the Pacific and North American plates. To the east, the northwest-trending Fairweather fault accommodates the movement with dextral slip of about 5.5 cm/yr (Plafker, Hudson, and others, 1978); to the west, the Pacific plate underthrusts Alaska at the Aleutian trench, which trends southwestward (Plafker 1969). The USGS has operated a telemetered seismic network in southern Alaska since 1971 and it was greatly expanded along the eastern Gulf of Alaska in September 1974. The current configuration of stations is shown in Figure 9. Technical details of the network are available in published earthquake catalogs (Lahr, Page, and others, 1974; Fogleman, Stephens, and others, 1978). Preliminary analysis of the data from this network covering the time period September 1, 1978 through March 10, 1979, as well as worldwide data for the main shock will be discussed in this paper.

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USGS1987

Index to limnological data for southcentral Alaska Lakes

South-central Alaska lakes are a valuable natural resource and provide a variety of recreational opportunities to the public. Lakeside development has increased significantly in the past 10 years and several south-central Alaskan lakes have documented pollution problems. Cultural eutrophication, the process by which man-induced nutrient loading to a lake results in large increases in biological productivity, can also produce noxious algae blooms, dissolved oxygen depletion at depth, reduced water transparency, and fish kills. The potential for cultural eutrophication of south-central Alaska lakes prompted the U.S. Geological Survey (USGS) Water Resources Division and the Alaska Department of Natural Resources-Division of Geological and Geophysical Surveys (ADGGS) to provide lake researchers, managers, and the public with this index of published historical and current limnological references. The purpose of the index is to provide reference to the data which can be used to identify and monitor cultural eutrophication of south-central Alaska lakes. (Lantz-PTT)

Open-File Report↗

USGS1996

Snow-depth and water-equivalent data for the Fairbanks area, Alaska, spring 1995

Snow depths at 34 sites and snow-water equivalents at 13 sites in the Fairbanks area were monitored during the 1995 snowmelt period (March 30 to April 26) in the spring of 1995. The U.S. Geological Survey conducted this study in cooperation with the Fairbanks International Airport, the University of Alaska Fairbanks, the Alaska Department of Natural Resources-Division of Mining and Water Management, the U.S Army, Alaska, and the U.S. Army Corps of Engineers-Alaska District. These data were collected to provide information about potential recharge of the ground-and surface-water systems during the snowmelt period in the Fairbanks area. This information is needed by companion geohydrologic studies of areas with known or suspected contaminants in the subsurface. Data-collection sites selected had open, boggy, wooded, or brushy vegetation cover and had different slope aspects. The deepest snow at any site, 27.1 inches, was recorded on April 1, 1995; the shallowest snow measured that day was 19.1 inches. The snow-water equivalents at these two sites were 5.9 inches and 4.5 inches, respectively. Snow depths and water equivalents were comparatively greater at open and bog sites than at wooded or brushy sites. Snow depths and water equivalents at all sites decreased throughout the measuring period. The decrease was more rapid at open and boggy sites than at wooded and brushy sites. Snow had completely disappeared from all sites by April 26, 1995.

Open-File Report↗

USGS1998

Stratiform zinc-lead mineralization in Nasina assemblage rocks of the Yukon-Tanana Upland in east-central Alaska

The Yukon-Tanana Upland of east-central Alaska and Yukon comprises thrust sheets of ductilely deformed metasedimentary and metaigneous rocks of uncertain age and origin that are overlain by klippen of weakly metamorphosed oceanic rocks of the Seventymile-Slide Mountain terrane, and intruded by post-kinematic Early Jurassic, Cretaceous and Tertiary granitoids. Metamorphosed continental margin strata in the Yukon-Tanana Upland of east-central Alaska are thought to be correlative, on the basis of stratigraphic similarities and sparse Mississippian U-Pb zircon and fossil ages (Mortensen, 1992), with middle Paleozoic metasedimentary and metavolcanic rocks in the eastern Alaska Range and in western and southeastern Yukon. Furthermore, rocks in the northern Yukon-Tanana Upland may correlate across the Tintina fault with unmetamorphosed counterparts in the Selwyn Basin (Murphy and Abbott, 1995). Volcanic-hosted (VMS) and sedimentary exhalative (sedex) massive sulfide occurrences are widely reported for these other areas (green-colored unit of fig. 1) but, as yet, have not been documented in the Alaskan part of the Yukon-Tanana Upland. Recent discoveries of VMS deposits in Devono-Mississippian metavolcanic rocks in the Finlayson Lake area of southeastern Yukon (Hunt, 1997) have increased the potential for finding VMS deposits in rocks of similar lithology and age in the Yukon-Tanana Upland of Alaska. Restoration of 450 km of early Tertiary dextral movement along the Tintina fault juxtaposes these two areas.

Alaska↗

USGS1999

Alaska digital aeromagnetic database description

Northwest Geophysical Associates, Inc. (NGA) was contracted by the U.S. Geological Survey (USGS) to construct a database containing original aeromagnotic data (in digital form) from surveys, maps and grids for the State of Alaska from existing public-domain magnetic data. This database facilitates thedetailed study and interpretation of aeromagnetic data along flightline profiles and allows construction of custom grids for selected regions of Alaska. The database is linked to and reflect? the work from the statewide gridded compilation completed under a prior contract. The statewide gridded compilation is also described in Saltus and Simmons (1997) and in Saltus and others (1999). The database area generally covers the on-shore portion of the State of Alaska and the northern Gulf of Alaska excluding the Aleutian Islands. The area extends from 54'N to 72'N latitude and 129'W to 169'W longitude. The database includes the 85 surveys that were included in the previous statewide gridded compilation. Figure (1) shows the extents of the 85 individual data sets included in the statewide grids. NGA subcontracted a significant portion of the work described in this report to Paterson, Grant, and Watson Limited (PGW). Prior work by PGW (described in Meyer and Saltus, 1995 and Meyer and others, 1998) for the interior portion of Alrska (INTAK) is included in this present study. The previous PGW project compiled 25 of the 85 surveys included in the statewide grids. PGW also contributed 10 additional data sets that were not included in either of the prior contracts or the statewide grids. These additional data sets are included in the current project in the interest of making the database as complete as possible. Figure (2) shows the location of the additional data sets.

Alaska↗

USGS2002

Studies by the U.S. Geological Survey in Alaska, 2000

The collection of eight papers that follow continue the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. The series presents new and sometimes-preliminary findings that are of interest to earth scientists in academia, government, and industry; to land and resource managers; and to the general public. Reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State (fig. 1), serving to emphasize the diversity of USGS efforts to meet the Nation's needs for earth-science information in Alaska. The papers in this volume are organized under the topics Geologic Framework, Resources, and Environment and Climate. This organization is intended to reflect the scope and objectives of current USGS geologic programs in Alaska. In particular, Geologic Framework studies provide background information that is the scientific basis for present and future earth-science investigations.

Alaska↗

USGS2005

Studies by the U.S. Geological Survey in Alaska, 2004

The collection of six papers that follow continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation's needs for Earth-science information in Alaska. This professional paper is the first 'online only' version of Studies by the U.S. Geological Survey in Alaska, reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Professional Paper↗

USGS2006

Studies by the U.S. Geological Survey in Alaska, 2005

Summary The collection of papers that follows continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation’s needs for Earth-science information in Alaska. This professional paper is one of a series of “online only” versions of Studies by the U.S. Geological Survey in Alaska , reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Alaska↗

USGS2009

Studies by the U.S. Geological Survey in Alaska, 2007

The collection of papers that follow continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation's needs for Earth-science information in Alaska. This professional paper is one of a series of 'online only' versions of Studies by the U.S. Geological Survey in Alaska, reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Professional Paper↗

USGS2010

Studies by the U.S. Geological Survey in Alaska, 2008-2009

Professional Paper↗

USGS2011

Studies by the U.S. Geological Survey in Alaska, 2010

The collection of papers that follows continues the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. This series represents new and sometimes-preliminary findings that are of interest to Earth scientists in academia, government, and industry; to land and resource managers; and to the general public. The reports presented in Studies by the U.S. Geological Survey in Alaska cover a broad spectrum of topics from various parts of the State, serving to emphasize the diversity of USGS efforts to meet the Nation’s needs for Earth-science information in Alaska. This professional paper is one of a series of “online only” versions of Studies by the U.S. Geological Survey in Alaska , reflecting the current trend toward disseminating research results on the World Wide Web with rapid posting of completed reports.

Alaska↗