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The report contains summaries of projects and activities in the Tennessee District of the U.S. Geological Survey, U.S. Department of the Interior,from 1995-96. Each summary includes the location, the objective of the project, the progress of the study to date, and the names of the cooperators and the project chiefs.
The Volcano Hazards Program of the U.S. Geological Survey (USGS) is part of the Geologic Hazards Assessments subactivity as funded by Congressional appropriation. Investigations are carried out in the Geologic and Water Resources Divisions of the USGS and with cooperators at the Alaska Division of Geological and Geophysical Surveys, University of Alaska Fairbanks Geophysical Institute, University of Utah, and University of Washington Geophysics Program. This report lists publications from all these institutions. This report contains only published papers and maps; numerous abstracts produced for presentations at scientific meetings have not been included. Publications are included based on date of publication with no attempt to assign them to Fiscal Year.
In 1965 a cooperative investigation with the U.S. Geological Survey produced Water Atlas No. 1 (Twenter and Coble, 1965). It presented information on the occurrence, availability, use, quality, and future demand of water in 10 counties in the central part of the state. Subsequent investigations produced Water Atlases No. 4 (Coble and Roberts, 1971) for southeast Iowa, No. 5 (Cagle and Heinitz, 1978) for south-central Iowa, No. 6 (Wahl et al., 1978) for east-central Iowa, and No. 7 (Buchmiller et al., 1985) for north-central Iowa. The present study, Water Atlas No. 8 (1989), describes the surface-water and groundwater resources of 11 counties in extreme northeast Iowa. With the publication of this report, water atlases are now available for the eastern two-thirds of the state.
This report combines and brings up-to-date the information previously given in Trace Elements Investigations Report 325, "Numerical list of U.S. Geological Survey Trace Elements Reports to April 30, 1953," and Trace Elements Investigations Report 301, "Topical index and bibliography of U.S. Geological Survey Trace Elements and related reports." Part I is a numerical list of U.S. Geological Survey Trace Elements Investigations and Memorandum reports. It supersedes TEI-325. This part lists not only reports (followed by a date) that have been transmitted to the U.S. Atomic Energy Commission, but also reports in preparation (followed by an asterisk) for which tentative titles were available on December 31, 1953. Reports that have been published are indicated by the abbreviation of the medium of publication. (See also part II.) Part II is a reference guide to Trace Elements and related reports that are available to the public; this part supersedes Part 2 of the TEI-301 (published as Geological survey Circular 281). These reports are grouped according to the type of publication or release. Abstracts published in Nuclear Science Abstracts are not included in Part II, although certain TEI and TEM reports, the abstracts of which have been published in NSA, are so indicated in Part I. Publications in process on December 31, 1953, are designated by an asterisk. Part III is a finding list of states, areas, and subjects. It is based on information derived mostly from the titles of reports and, where titles are of a general nature, from a cursory review of the reports. This list is not a complete index of the information given in Trace Elements and related reports, but is designed to find subjects of major interest. Because of the numerous entries for Colorado and Utah, information has been listed by counties and, where possible, by subject under these states. Other states have county listings only if a county is included in the title of a report; otherwise, areas may be listed separately under the state. Major subjects are listed separately in the index and also where appropriate under states. Analytical methods and subjects related to analytical research are listed under Analytical Methods and Research, but not separately throughout the index. Most mineralogic studies are included under the heading Mineralogy, but are not necessarily listed according to location. Part IV is a finding list of authors. The words “with” and “and” are used to indicate seniority of authorship. For example, a listing of Jones and Brown indicates that Jones is the senior author. A listing of Jones with Brown indicates that Brown is the senior author. In both parts III and IV all Trace Elements reports are listed, as well as other related reports that have not been issued as Trace Elements reports. The following standard abbreviations have been used: TEI, Trace Elements Investigations report; TEM, Trace Elements Memorandum report; P, Professional Paper; B, Bulletin; C, Circular; J, Journal; OF, open file; TIS, Technical Information Service release; NSA, Nuclear Science Abstracts; QM, Quadrangle Map Series; and OM, Oil and Gas map or Mineral Investigations map or report.
The Big Lost River Basin, located in parts of Butte and Custer Counties in south-central Idaho, supports the communities surrounding the cities of Arco, Leslie, Mackay, and Moore and provides for agricultural resources that depend on a sustainable supply of surface water from the Big Lost River and its tributaries and groundwater from an unconfined aquifer. The aquifer, situated in a structurally controlled intermontane valley, is composed of unconsolidated alluvium, consolidated sedimentary and volcanic rocks, and younger interbedded volcanic rocks. This report presents two separate groundwater budgets for the aquifer, one above and one below Mackay Dam, as well as a combined groundwater budget for the aquifer within the entire Big Lost River Basin. The budgets span a 20-year period (2000–19), characterizing average conditions, a dry year (2014), and a wet year (2017). The groundwater budgets will help address questions regarding the availability of groundwater supply in the Big Lost River Basin and inform future groundwater modeling. The Idaho Geological Survey has prepared the groundwater budgets as part of a larger hydrogeologic investigation completed by the U.S. Geological Survey and the Idaho Geological Survey in cooperation with the Idaho Department of Water Resources during 2018–21. Other reports describe the hydrogeologic framework and several streamflow-measurement events to evaluate gains and losses on the Big Lost River. Collectively, these reports provide an updated characterization of groundwater resources in the Big Lost River Basin which will help address water resources challenges. A groundwater budget is a conceptual and numerical accounting of inflow (recharge) to groundwater and outflow (discharge) from groundwater. The predominant sources of recharge to the aquifer include losing river reaches (33 percent), areal recharge (as precipitation less evapotranspiration and surface runoff, comprising about 23 percent of the total inflow), tributary canyon underflow from higher altitudes (20 percent), canal seepage (13 percent), recharge through applied irrigation on fields below the root zone and other minor sources (11 percent), and Mackay Reservoir seepage (less than 1 percent). The primary sources of discharge from the aquifer are groundwater pumpage to meet irrigation demand, domestic supply, and municipal supply (76 percent) and gaining river reaches (24 percent). The positive or negative difference between the sum of all inflows and outflows is regarded as the residual, representing the change in groundwater storage, groundwater outflow from the basin or subbasins, and uncertainty and errors in the budget. In the Big Lost River Basin, groundwater outflow is at the mouth of the basin below Arco into the eastern Snake River Plain aquifer. The total mean annual estimated recharge to the Big Lost River Basin was 439,100 acre-feet per year (acre-ft/yr; 607 cubic feet per second [ft 3 /s]) for 2000–19, 373,900 acre-ft/yr (516 ft 3 /s) in 2014, and 762,100 acre-ft/yr (1,053 ft 3 /s) in 2017. The mean annual estimated groundwater discharge from the aquifer was about 112,300 acre-ft/yr (155 ft 3 /s) for 2000–19, 153,500 acre-ft/yr (212 ft 3 /s) in 2014, and 53,400 acre-ft/yr (74 ft 3 /s) in 2017. The estimated mean annual groundwater residual was 326,800 acre-ft/yr (451 ft 3 /s) for 2000–19, 220,400 acre-ft/yr (304 ft 3 /s) in 2014, and 708,700 acre-ft/yr (979 ft 3 /s) in 2017. The mean annual residual above Mackay Dam was 100,400 acre-ft/yr (2000-19), 96,700 acre-ft (2014), and 248,300 acre-ft (2017). The mean annual residual contribution below Mackay Dam, minus any groundwater-flow above Mackay Dam, was 226,400 acre-ft/yr (2000-19), 123,700 acre-ft (2014), and 460,400 acre-ft (2017). These results are highly sensitive to assumptions about certain budget inflow parameters. In particular, the magnitude of the budget residuals during especially dry and wet periods is amplified by the groundwater-budget terms tributary streamflow and tributary underflow that contribute appreciable recharge but also have high uncertainty. The results of the groundwater-budget evaluation describe an interconnected and complex hydrologic response throughout the basin to various climatic and water-use trends. The part of the basin above Mackay Dam typically has a positive groundwater residual derived from snowmelt recharge to tributary canyons and areal recharge in excess of groundwater pumpage for irrigation demand. This supply is used to meet irrigation demand above Mackay Dam and to provide for water supply below Mackay Dam. On average, groundwater inflow from above Mackay Dam to below Mackay Dam, assuming negligible reservoir storage effects, accounts for about 25 percent of the total groundwater recharge below Mackay Dam. Considerable recharge to groundwater below Mackay Dam occurs through seepage from the Big Lost River and canals and ditches. Most groundwater discharge from the aquifer is through irrigation pumping. The water supply below Mackay Dam is highly dependent on available upstream surface-water flows, the magnitude of the groundwater residual from above Mackay Dam, and annual variability in local groundwater conditions.
Recent geodetic, geologic, and seismologic studies show that the south-central coast of California is a region of active Quaternary deformation. Northeast-directed crustal shortening is occurring in a triangular-shaped region between the Hosgri-San Simeon fault system on the west, the Southern Coast Ranges on the northeast, and the western Transverse Ranges on the south. We informally call this region the Los Osos domain. In this study, we conducted detailed geological, seismological, and geophysical investigations to characterize the nature and rates of deformation in the domain. Locations of active and potentially active faults and folds are compiled at a scale of 1:250,000 for the entire domain based primarily on onshore geologic data and offshore geophysical data. Crustal shortening in the domain is accommodated by a series of prominent northwest-trending reverse faults and localized folding. The reverse faults separate distinct structural blocks that have little or no internal deformation. Hangingwall blocks are being uplifted at rates of up to 0.2 mm/yr. Footwall blocks are either static or slowly subsiding at rates of 0.1 mm/yr or less, except for localized areas of concentrated subsidence directly adjacent to some faults. The cumulative rate of crustal shortening is about 1 to 2 mm/yr across the northern part of the domain based on observed geologic deformation. Cumulative shortening across the central and southern parts of the domain is poorly constrained by geologic data and may approach 2 to 3 mm/yr. Historical and instrumental seismicity generally are spatially associated with the uplifted blocks and bordering reverse faults to depths of about 10 km. Together with near-surface geological data and deeper crustal geophysical imaging that show high-angle faulting, the seismicity data indicate that the reverse faults probably extend to the base of the seismogenic crust. The base of the seismogenic crust may correspond with a mid-crustal detachment or decollement surface into which the reverse faults root. We speculate that the detachment may coincide, in part, with the top of a northeast-dipping slab of oceanic crust that extends beneath the western margin of the continent or with the brittle-ductile transition above the subducted slab. The Los Osos domain of north-northeast/south-southwest crustal shortening is structurally detached from the offshore Hosgri Fault Zones. Both the pattern and regional extent of deformation in the Los Osos domain contrast sharply with that of the offshore Santa Maria Basin. The basin is undergoing minor east-northeast/west-southwest crustal shortening at rates of less than 0.1 mm/yr and is moving northwestward at a rate of about 1 to 3 mm/yr relative to the Los Osos domain along the San Simeon and Hosgri Fault Zones. Geodetic data and the kinematics of north-northeast-directed crustal shortening of the Los Osos domain east of the Hosgri Fault Zone show that the rate and cumulative amount of right-slip along the Hosgri Fault Zone progressively decrease southward. Quaternary deformation within the Los Osos domain is related to distributed dextral simple shear associated with Pacific-North American plate motion. Paleomagnetic data show that clockwise rotation of the western Transverse Ranges has occurred along the southern boundary of the domain during the past 6 m.y. During this time, the Salinian crustal block, which forms the eastern boundary of the Los Osos domain, has remained relatively stable. Internal shortening of the Los Osos domain has accommodated the relative motions of these bordering crustal blocks, particularly the rotation of the western Transverse Ranges.
This bulletin has been prepared primarily with a view to securing prompt publication of the economic results of investigations by the United States Geological Survey. It is designed to meet the wants of the busy man, and is so condensed that he will be able to obtain results and conclusions with a minimum expenditure of time and energy. It also affords a better idea of the work which the Survey as an organization is-carrying on for the direct advancement of mining interests throughout the country than can readily be obtained from the more voluminous reports. Should this bulletin be favorably received by those interested in the development of the mineral industries of the United States, it is proposed to publish early in each calendar year a similar bulletin containing the results of the last year's field work in economic geology. In the preparation of the present volume, promptness of publication has been made secondary only to the economic utility of the material presented. The papers included are such only as have a direct economic bearing, all questions of purely scientific interest being excluded. The papers represent three classes : (1) Preliminary discussions of the results of extended economic investigations, which will later be published by the Survey in more detailed form; (2) comparatively detailed descriptions of occurrences of economic interest, noted by geologists of the Survey in the course of their field work, but not of sufficient importance to necessitate a later and more extended description; (3) abstracts of certain economic papers which have appeared in Survey publications during the last year, chiefly such as give a general account of the distribution and mode of occurrence of particular mineral deposits throughout the United States. The papers have been grouped according to the subjects treated. At the end of each section is given a list of previous publications on that subject by this Survey. These lists will be found serviceable by those who wish to ascertain what has been accomplished by the Survey in the investigation of any particular group of mineral products. They are generally confined to Survey publications, though a few titles of important papers published elsewhere by members of the Survey are included.
Mineral resources of the Greenville 1° x 2° quadrangle, South Carolina, Georgia, and North Carolina, were assessed between 1984 and 1990 under the Conterminuous United States Mineral Assessment Program (CUSMAP) of the U.S. Geological Survey (USGS). The mineral resource assessments were made on the basis of geologic, geochemical, and geophysical investigations and on the distribution of mines, prospects and mineral occurrences reported in the literature. This report is an assessment of the mineral resources associated with mafic and ultramafic rocks in the Greenville quadrangle. It is based on the geology as mapped by Nelson and others (1987, 1989), on geochemistry of rock samples collected for this and other studies, on data available for known mines and prospects, and on the published geologic literature.
The Glen Torridon (GT) region within Gale crater, Mars, occurs in contact with the southern side of Vera Rubin ridge (VRR), a well-defined geomorphic feature that is comparatively resistant to erosion. Prior to detailed ground-based investigation of GT, its geologic relationship with VRR was unknown. Distinct lithologic subunits within the Jura member (Murray formation), which forms the upper part of VRR, made it possible to be also identified within GT. This indicates that the strata pass across the geomorphic divide between regions. Furthermore, the cross-bedded lower part of the overlying Knockfarril Hill member (Carolyn Shoemaker formation) also occurs within both VRR and GT. Correlation of both units demonstrates that the strata form a continuous stratigraphic succession regardless of large-scale geomorphic expression. The lithologic change from mudstone (Jura member) to cross-bedded sandstone (Knockfarril Hill member) heralds a significant shift in paleoenvironment from lacustrine to fluvial. The upper part of the Knockfarril Hill member consists of interbedded mudstone and sandstone that transitions to the overlying finely laminated mudstone of the Glasgow member, and a return to lacustrine deposition. In GT, the Stimson formation unconformably overlies the Glasgow member, where it demarks the southern boundary of GT. Contacts for each stratigraphic unit were defined and transferred to a high-resolution image base to make a geologic map and cross sections perpendicular to the NE strike. Stratal dips cannot exceed 2° NW to retain the positions of stratigraphic units in the locations they are exposed throughout GT.
The bedrock exposed in the Low Wassie Quadrangle, Missouri, comprises Late Cambrian and Early Ordovician aged dolomite, sandstone, and chert. The sedimentary rocks are nearly flat-lying except where they are adjacent to faults. The carbonates are karstified and the area contains numerous sinkholes, springs, caves, and losing-streams. This map is one of several being produced under the U.S. Geological Survey National Cooperative Geologic Mapping Program to provide geologic data applicable to land-use problems in the Ozarks of south-central Missouri. Ongoing and potential industrial and agricultural development in the Ozarks region has presented issues of ground-water quality in karst areas. A National Park in this region (Ozark National Scenic Riverways, Missouri ) is concerned about the effects of activities in areas outside of their stewardship on the water resources that define the heart of this Park. This task applies geologic mapping and karst investigations to address issues surrounding competing land use in south-central Missouri. This task keeps geologists from the USGS associated with the park and allows the Parks to utilize USGS expertise and aid the NPS on how to effectively use geologic maps for Park management. For more information see: http://geology.er.usgs.gov/eespteam/Karst/index.html.
The bedrock exposed in the Winona Quadrangle, Missouri, comprises Mesoproterozoic aged volcanic rocks overlain by Late Cambrian and Early Ordovician aged dolomite, sandstone, and chert. The sedimentary rocks are nearly flat-lying except where they drape around knobs of the volcanic rocks or where they are adjacent to faults. The carbonates are karstified and the area contains numerous sinkholes, springs, caves, and losing-streams. This map is one of several being produced under the U.S. Geological Survey National Cooperative Geologic Mapping Program to provide geologic data applicable to land-use problems in the Ozarks of south-central Missouri. Ongoing and potential industrial and agricultural development in the Ozarks region has presented issues of ground-water quality in karst areas. A National Park in this region (Ozark National Scenic Riverways, Missouri ) is concerned about the effects of activities in areas outside of their stewardship on the water resources that define the heart of this Park. This task applies geologic mapping and karst investigations to address issues surrounding competing land use in south-central Missouri. This task keeps geologists from the USGS associated with the park and allows the Parks to utilize USGS expertise and aid the NPS on how to effectively use geologic maps for Park management. For more information see: http://geology.er.usgs.gov/eespteam/Karst/index.html
The bedrock exposed in the Stegall Mountain Quadrangle, Missouri, comprises Mesoproterozoic aged volcanic rocks overlain by Late Cambrian and Early Ordovician aged dolomite, sandstone, and chert. The sedimentary rocks are nearly flat-lying except where they drape around knobs of the volcanic rocks or where they are adjacent to faults. The carbonates are karstified and the area contains numerous sinkholes, springs, caves, and losing-streams. This map is one of several being produced under the U.S. Geological Survey National Cooperative Geologic Mapping Program to provide geologic data applicable to land-use problems in the Ozarks of south-central Missouri. Ongoing and potential industrial and agricultural development in the Ozarks region has presented issues of ground-water quality in karst areas. A National Park in this region (Ozark National Scenic Riverways, Missouri ) is concerned about the effects of activities in areas outside of their stewardship on the water resources that define the heart of this Park. This task applies geologic mapping and karst investigations to address issues surrounding competing land use in south-central Missouri. This task keeps geologists from the USGS associated with the park and allows the Parks to utilize USGS expertise and aid the NPS on how to effectively use geologic maps for Park management. For more information see: http://geology.er.usgs.gov/eespteam/Karst/index.html
The bedrock exposed in the Fremont Quadrangle, Missouri, comprises Early Ordovician aged dolomite, sandstone, and chert. The sedimentary rocks are nearly flat-lying except where they are adjacent to faults. The carbonate rocks are karstified and the area contains numerous sinkholes, springs, caves, and losing-streams. This map is one of several being produced under the U.S. Geological Survey National Cooperative Geologic Mapping Program to provide geologic data applicable to land-use problems in the Ozarks of south-central Missouri. Ongoing and potential industrial and agricultural development in the Ozarks region has presented issues of ground-water quality in karst areas. National Park in this region (Ozark National Scenic Riverways, Missouri) is concerned about the effects of activities in areas outside of their stewardship on the water resources that define the heart of this Park. This task applies geologic mapping and karst investigations to address issues surrounding competing land use in south-central Missouri. This task keeps geologists from the USGS associated with the park and allows the Parks to utilize USGS expertise and aid the NPS on how to effectively use geologic maps for Park management. For more information see: http://geology.er.usgs.gov/eespteam/Karst/index.html
The bedrock exposed in the Van Buren South quadrangle, Missouri, comprises Late Cambrian and Early Ordovician aged dolomite, sandstone, and chert. The sedimentary rocks are nearly flat-lying except where they are adjacent to faults. The carbonate rocks are karstified and the area contains numerous sinkholes, springs, caves, and losing-streams. This map is one of several being produced under the U.S. Geological Survey National Cooperative Geologic Mapping Program to provide geologic data applicable to land-use problems in the Ozarks of south-central Missouri. Ongoing and potential industrial and agricultural development in the Ozarks region has presented issues of ground-water quality in karst areas. A National Park in this region (Ozark National Scenic Riverways, Missouri ) is concerned about the effects of activities in areas outside of their stewardship on the water resources that define the heart of this Park. This task applies geologic mapping and karst investigations to address issues surrounding competing land use in south-central Missouri. This task keeps geologists from the USGS associated with the park and allows the Parks to utilize USGS expertise and aid the NPS on how to effectively use geologic maps for Park management. For more information see: http://geology.er.usgs.gov/eespteam/Karst/index.html
The bedrock exposed in the Big Spring quadrangle of Missouri comprises Late Cambrian and Early Ordovician aged dolomite, sandstone, and chert. The sedimentary rocks are nearly flat lying except where they are adjacent to faults. The carbonate rocks are karstified, and the area contains numerous sinkholes, springs, caves, and losing streams. This map is one of several being produced under the U.S. Geological Survey (USGS) National Cooperative Geologic Mapping Program to provide geologic data applicable to land-use problems in the Ozarks of south-central Missouri. Ongoing and potential industrial and agricultural development in the Ozarks region has presented issues of ground-water quality in karst areas. A national park in this region (Ozark National Scenic Riverways, Missouri) is concerned about the effects of activities in areas outside of their stewardship on the water resources that define the heart of this park. This task applies geologic mapping and karst investigations to address issues surrounding competing land use in south-central Missouri. This task keeps geologists from the USGS associated with the park and allows the park to utilize USGS expertise and aid the NPS on how to effectively use geologic maps for park management. For more information, see: http://geology.er.usgs.gov/eespteam/Karst/index.html
The United States Geological Survey is currently investigating the ground-water resources of Connecticut in cooperation with the State Water Commission. As part of this cooperative project, in order to summarize the knowledge already gained about ground water in the State, a bibliography of reports dealing with ground water in Connecticut has been prepared. A compilation entitled "Bibliography and index of publications relating to ground water prepared by the Geological Survey and cooperating agencies", by G. A. Waring and O. E. Neinzer, was issued as U.S. Geological Survey Water-Supply Paper 992 in 1947. The following compilation lists all the papers in Water-Supply Paper 992 that refer to Connecticut plus other short reports not included in the letter. The first studies of ground water in Connecticut were begun in 1903 by Professor H. E. Gregory of Yale University under the auspices of the U.S. Geological Survey. The early studies were of the reconnaissance type, covering large sections of the State, and were concerned mainly with the relation of the bedrock geology to the water supply. The results were published in several Water-Supply Papers of the Geological Survey. In 1911 a cooperative agreement for the study of the ground-water resources of Connecticut in which each party shared equally in the expenses was made between the Federal Survey and the Connecticut State Geological and Natural History Survey. As a result more detailed studies in smaller areas were undertaken. Active field work covering more than half the State was continued through 1923 under this arrangement and the results published in eight U.S. Geological Survey Water-Supply Papers. After an eleven year period of inactivity and with the inauguration of the Federal Emergency Relief Commission, detailed studies of ground water in Connecticut were begun again in October 1934 as a project of the Emergency Relief Commission (later the Works Progress Administration). The project was sponsored by the Connecticut State Water Commission, the State Planning Board, and the U.S. Geological Survey. The technical direction of the work was undertaken by the Geological Survey. The project consisted of an inventory and mapping of wells and springs in the State by towns and the recording of weekly observations of water levels in selected wells. The data collected through October 1939 were published in six mimeographed bulletins and one typewritten bulletin by the Works Program Administration. In 1939, when it became necessary to curtail the work being carried on by the Works Progress Administration, cooperation was arranged between the Federal Ecological Survey and the State Water Commission to continue investigations relative to the over-development of ground-water supplies in the New Haven area. From time to time additional funds have been made available to meet growing demands by the State for data on its ground-water supplied and the present cooperative program between the U.S. Geological Survey and the State Water Commission is a continuation of the original arrangement. It is estimated that about 14 per cont of the State has been covered by recent ground-water surveys and in addition some data are available for another 20 per cent of he State.
The U.S. Geological Survey (USGS) has initiated a multi-disciplinary study investigating the applicability of remote sensing technologies for geologic mapping and identification of prospective areas for base and precious metal deposits in remote parts of Alaska. The Kahiltna terrane in southwestern Alaska was selected for investigation because of its known mineral deposits and potential for additional mineral resources. An assortment of technologies is being investigated to aid in remote analysis of terrain, and includes imaging spectroscopy (hyperspectral remote sensing), high spatial resolution electro-optical imagery, and Synthetic Aperture Radar (SAR). However, there are significant challenges to applying imaging spectroscopy and electro-optical imagery technologies in this area because of the low solar angle for parts of the year, seasonal periods of darkness and snow cover, and the frequently cloudy weather that characterizes Alaska. Synthetic Aperture Radar (SAR) was selected because this technology does not rely on solar illumination and has all-weather capability. The USGS has compiled a continuous, cloud-free 12.5-meter resolution radar mosaic of SAR data of approximately 212,000 square kilometers to examine the suitability of this technology for geologic mapping. This mosaic was created from Advanced Land Observing Satellite (ALOS) Phased Array type L-band Synthetic Aperture Radar (PALSAR) data collected from 2007 to 2010 spanning the Kahiltna terrane and the surrounding area. Interpretation of these data may help geologists understand past geologic processes and identify areas with potential for near-surface mineral resources for further ground-based geological and geochemical investigations.
This report, which covers the period August 25, 1961 to August 24, 1962, is the third of a series describing the program of research conducted by the U.S. Geological Survey on behalf of the National Aeronautics and Space Administration. The major long-range objectives of the program are to determine and map the stratigraphy and structure of the Moon's crust, to work out from these the sequence of events that led to the present condition of the Moon's surface, and to determine the processes by which these events took place. This report is presented in four parts with a separate summary. Part A: Lunar and planetary investigations (with map supplement). Geologic mapping of the Moon involves discrimination of the different materials exposed on the lunar surface and their assignment to geologic units, the determination of the photometric characteristics of these materials, delineation of the boundaries of the units and determination of their stratigraphic sequence. Part B: Crater investigations. These include field studies of terrestrial craters, hypervelocity impact experiments with rocks and other materials, studies of the behavior of rocks under high shock loads, and experimental and field studies of shock metamorphism in rocks. Part C: Cosmochemistry and petrography. Studies are being made of the chemical, petrographic, and physical properties of materials of extraterrestrial origin and of certain materials associated with terrestrial impact structures. The studies reported in Part C are concerned with tektites, terrestrial impactites, metallic spherules formed by the Meteor Crater impact event, and particles of possible cosmic origin. Part D: Studies for space flight program. These studies are undertaken to aid in the design of space flight experiments and the planning of space missions. The report that makes up Part D is an evaluation of the lunar flux of secondary particles derived from primary impact events on the lunar surface.