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At least 1,207 records · Page 67Linked to original sources

Hawaiian Volcano Observatory record book 1963

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1963, 1964, and 1965

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1965

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Nuclear event time histories and computed site transfer functions for locations in the Los Angeles region

This report presents a collection of Nevada Test Site (NTS) nuclear explosion recordings obtained at sites in the greater Los Angeles, Calif., region. The report includes ground velocity time histories, as well as, derived site transfer functions. These data have been collected as part of a study to evaluate the validity of using low-level ground motions to predict the frequency-dependent response of a site during an earthquake. For this study 19 nuclear events were recorded at 98 separate locations. Some of these sites have recorded more than one of the nuclear explosions, and, consequently, there are a total of 159, three-component station records. The location of all the recording sites are shown in figures 1–5, the station coordinates and abbreviations are given in table 1. The station addresses are listed in table 2, and the nuclear explosions that were recorded are listed in table 3. The recording sites were chosen on the basis of three criteria: (1) that the underlying geological conditions were representative of conditions over significant areas of the region, (2) that the site was the location of a strong-motion recording of the 1971 San Fernando earthquake, or (3) that more complete geographical coverage was required in that location.

California↗

Physiography and Quaternary geology of the San Juan Mountains, Colorado

The scenic beauty, rugged contour, and great variety of geologic phenomena displayed by the San Juan Mountains of southwestern Colorado have lured to that region many geologists, both professional and amateur, as well as countless laymen. Serious geologic studies in these mountains seem to fall historically into three periods. The first of these covers the work of the geologists and topographers of the United States Geological and Geographical Survey of the Territories. Field studies were prosecuted under the general direction of F. V. Hayden in this region from 1869 to 1876, and the results obtained were published among the monographs of the Hayden Survey. The second period of geologic examinations began in 1887, when Whitman Cross undertook investigations of certain of the mining districts in the San Juan region, which by that time had attracted much attention in the mining world. The results of this second series of studies have appeared from time to time as folios"' of the Geologic Atlas and reports on the economic geology of the mining districts, published by the United States Geological Survey between 1899 and 1910. Gradually the concept of the geologic problems was changed. Instead of considering individual mining districts as the units of investigation it became apparent that the San Juan region must itself be the unit. In 1908 Mr. Cross drafted plans for the completion of the San Juan studies on this enlarged basis. His aim was to arrange for the publication of papers on different subjects rather than one huge monograph on the region as a whole.

Colorado, New Mexico↗

Optically stimulated luminescence dating of aeolian sand in the otindag dune field and holocene climate change

The dune system in Otindag sand field of northern China is sensitive to climate change, where effective moisture and related vegetation cover play a controlling role for dune activity and stability. Therefore, aeolian deposits may be an archive of past environmental changes, possibly at the millennial scale, but previous studies on this topic have rarely been reported. In this study, thirty-five optically stimulated luminescence (OSL) ages of ten representative sand-paleosol profiles in Otindag sand field are obtained, and these ages provide a relatively complete and well-dated chronology for wet and dry variations in Holocene. The results indicate that widespread dune mobilization occurred from 9.9 to 8.2 ka, suggesting a dry early Holocene climate. The dunes were mainly stabilized between 8.0 and 2.7 ka, implying a relatively wet climate, although there were short-term penetrations of dune activity during this wet period. After ???2.3 ka, the region became dry again, as inferred from widespread dune activity. The "8.2 ka" cold event and the Little Ice Age climatic deterioration are detected on the basis of the dune records and OSL ages. During the Medieval Warm Period and the Sui-Tang Warm Period (570-770 AD), climate in Otindag sand field was relatively humid and the vegetation was denser, and the sand dunes were stabilized again. These aeolian records may indicate climate changes at millennial time scale during Holocene, and these climatic changes may be the teleconnection to the climate changes elsewhere in the world. ?? Science in China Press and Springer-Verlag GmbH 2008.

Science in China, Series D: Earth Sciences↗

U.S. Department of Energy's Regional Carbon Sequestration Partnership Program: Overview

The U.S. Department of Energy (DOE) has formed a nationwide network of seven regional partnerships to help determine the best approaches for capturing and permanently storing gases that can contribute to global climate change. The Regional Carbon Sequestration Partnerships (RCSPs) are tasked with determining the most suitable technologies, regulations, and infrastructure for carbon capture, transport, and storage in their areas of the country and parts of Canada. The seven partnerships include more than 350 state agencies, universities, national laboratories, private companies, and environmental organizations, spanning 42 states, two Indian nations, and four Canadian provinces. The Regional Partnerships initiative is being implemented in three phases: ???Characterization Phase (2003-2005): The objective was to collect data on CO 2 sources and sinks and develop the human capital to support and enable future carbon sequestration field tests and deployments. The completion of this Phase was marked by release of the Carbon Sequestration Atlas of the United States and Canada-Version 1 which included a common methodology for capacity assessment and reported over 3,000GT of storage capacity in saline formations, depleted oil and gas fields, and coal seams.???Validation Phase (2005-2009): The objective is to plan and implement small-scale (<1??million tons CO 2 ) field testing of storage technologies in areas determined to be favorable for carbon storage. The partnerships are currently conducting over 20 small-scale geologic field tests and 11 terrestrial field tests.???Development Phase (2008-2018): The primary objective is the development of large-scale (>1??million tons of CO 2 ) Carbon Capture and Storage (CCS) projects, which will demonstrate that large volumes of CO 2 can be injected safely, permanently, and economically into geologic formations representative of large storage capacity. Even though the RCSP Program is being implemented in three phases, it should be viewed as an integrated whole, with many of the goals and objectives transitioning from one phase to the next. Accomplishments and results from the Characterization Phase have helped to refine goals and activities in the Validation and Deployment Phases. The RCSP Program encourages and requires open information sharing among its members by sponsoring both general workshops and meetings to facilitate information exchange. Although each RCSP has its own objectives and field tests, mutual cooperation has been an important part of the Program thus far. The primary goal of the RCSP initiative is to promote the development of a regional framework and the infrastructure necessary to validate and deploy carbon sequestration technologies within each Partnership's region. ?? 2009 Elsevier Ltd. All rights reserved.

Conference Paper↗

Extension of Gutenberg‐Richter distribution to MW −1.3, no lower limit in sight

With twelve years of seismic data from TauTona Gold Mine, South Africa, we show that mining‐induced earthquakes follow the Gutenberg‐Richter relation with no scale break down to the completeness level of the catalog, at moment magnitude M W −1.3. Events recorded during relatively quiet hours in 2006 indicate that catalog detection limitations, not earthquake source physics, controlled the previously reported minimum magnitude in this mine. Within the Natural Earthquake Laboratory in South African Mines (NELSAM) experiment's dense seismic array, earthquakes that exhibit shear failure at magnitudes as small as M W −3.9 are observed, but we find no evidence that M W −3.9 represents the minimum magnitude. In contrast to previous work, our results imply small nucleation zones and that earthquake processes in the mine can readily be scaled to those in either laboratory experiments or natural faults.

TauTona Mine↗

What common-garden experiments tell us about climate responses in plants

Common garden experiments are indoor or outdoor plantings of species or populations collected from multiple distinct geographic locations, grown together under shared conditions. These experiments examine a range of questions for theory and application using a variety of methods for analysis. The eight papers of this special feature comprise a cross section of contemporary approaches, summarized and synthesized here by what they tell us about the relationships between climate-related trait spectra and fitness optima. Four of the eight papers are based on field experiments in prairie, desert, Mediterranean and boreal biomes. Representative of many common garden experiments, these experiments reveal consistent evidence of traits varying with population climate provenance, but evidence of a tradeoff between growth and tolerance traits or of consistent fitness optimization at home is scant, in contrast to trait theory. Two synthesis papers highlight dominant patterns of trait divergence, including for an exotic invasive species. One theoretical paper warned that unknown kinship relationships between populations can result in the misidentification of adaptive trait divergence. A third synthesis paper formulated novel and ambitious goals for common-garden studies through including measurement of response variables at multiple levels of biological organization. The featured papers discuss multiple avenues for improving common garden studies. Genomic analysis, together with the quantification of kinship relationships, will continue to reveal the influence of environmental drivers on gene selection. Measuring a more complete set of fitness traits, especially for traits related to regeneration, will permit the development of projection models to explicitly link trait spectra, climate patterns and fitness consequences. More standardized data reporting will additionally improve abilities to synthesize findings across experiments. Testing population performance in competition with other species will produce more robust fitness comparisons between genotypes, especially for slower-growing genotypes in higher-resource environments. Adding gardens in and beyond climatic edge locations will furthermore strengthen the understanding of population failure and species exclusion. Finally, there is unrealized potential in adding ecosystem-level observations to common-garden studies that will enhance integrative analysis across scales of biological organization and scientific domains. Synthesis . With novel, creative designs, data integration and synthesis, common garden experiments will continue to advance the understanding of trait ensembles interacting with climate across scales of biological organization, provide pivotal data for global change models and guide ecological applications such as restoration of habitats for rare and climate sensitive species.

Journal of Ecology↗

State hydrologic unit maps

A set of maps depicting approved boundaries of, and numerical codes for, river-basin units of the United States has been developed by the U.S. Geological Survey. These ' State Hydrologic Unit Maps ' are four-color maps that present information on drainage, culture, hydrography, and hydrologic boundaries and codes: (1) the 21 major water-resources regions and the 222 subregions designated by the U.S. Water Resources Council; (2) the 352 accounting units of the U.S. Geological Survey 's National Water Data Network; and (3) the 2,149 cataloging units of the U.S. Geological Survey 's Catalog of Information on Water Data. The maps are plotted on the Geological Survey State base-map series at a scale of 1:500,000 and, except for Alaska, depict hydrologic unit boundaries for all drainage basins greater than 700 mi squared (1,813 km squared). A complete list of all the hydrologic units, along with their drainage areas, their names, and the names of the States or outlying areas in which they reside, is contained in the report. These maps and associated codes provide a standardized base for use by water-resources organizations in locating, storing, retrieving, and exchanging hydrologic data. The Hydrologic Unit Codes shown on the maps have been approved as a Federal Information Processing Standard for use by the Federal establishment. (USGS)

Open-File Report↗

Stratigraphic cross sections of the Niobrara interval of the Cody Shale and associated rocks in the Wind River Basin, central Wyoming

The Wind River Basin in Wyoming is one of many structural and sedimentary basins that formed in the Rocky Mountain foreland during the Laramide orogeny. The basin is nearly 200 miles long, 70 miles wide, and encompasses about 7,400 square miles in central Wyoming. The basin is bounded by the Washakie Range, Owl Creek uplift, and southern Bighorn Mountains on the north, the Casper arch on the east, the Granite Mountains on the south, and Wind River Range on the west. Many important conventional oil and gas fields producing from reservoirs ranging in age from Mississippian through Tertiary have been discovered in this basin. In addition, an extensive unconventional overpressured basin-centered gas accumulation has been identified in Cretaceous and Tertiary strata in the deeper parts of the basin. It has long been suggested that various Upper Cretaceous marine shales, including the Cody Shale, are the principal hydrocarbon source rocks for many of these accumulations. With recent advances and success in horizontal drilling and multistage fracture stimulation, there has been an increase in exploration and completion of wells in these marine shales in other Rocky Mountain Laramide basins that were traditionally thought of only as hydrocarbon source rocks. The two stratigraphic cross sections presented in this report were constructed as part of a project carried out by the U.S. Geological Survey to characterize and evaluate the undiscovered continuous (unconventional) oil and gas resources of the Niobrara interval of the Upper Cretaceous Cody Shale in the Wind River Basin in central Wyoming. The primary purpose of the cross sections is to show the stratigraphic relationship of the Niobrara equivalent strata and associated rocks in the lower part of the Cody Shale in the Wind River Basin. These two cross sections were constructed using borehole geophysical logs from 37 wells drilled for oil and gas exploration and production, and one surface section along East Sheep Creek near Shotgun Butte in the northwestern part of the basin. Both lines originate at the East Sheep Creek surface section and end near Clarkson Hill in the extreme southeastern part of the basin. The stratigraphic interval extends from the upper part of the Frontier Formation to the middle part of the Cody Shale. The datum is the base of the “chalk kick” marker bed, a distinctive resistivity peak or zone in the lower part of the Cody Shale. A gamma ray and (or) spontaneous potential (SP) log was used in combination with a resistivity log to identify and correlate units. Marine molluscan index fossils collected from nearby outcrop sections were projected into the subsurface to help determine the relative ages of the strata and aid in correlation.

Wyoming↗

Hydrogeologic characteristics and geospatial analysis of water-table changes in the alluvium of the lower Arkansas River Valley, southeastern Colorado, 2002, 2008, and 2015

The U.S. Geological Survey in cooperation with the Lower Arkansas Valley Water Conservancy District measures groundwater levels periodically in about 100 wells completed in the alluvial material of the Arkansas River Valley in Pueblo, Crowley, Otero, Bent, and Prowers Counties in southeastern Colorado, of which 95 are used for the analysis in this report. The purpose of this report is to provide information to water-resource administrators, managers, planners, and users about groundwater characteristics in the alluvium of the lower Arkansas Valley extending roughly 150 miles between Pueblo Reservoir and the Colorado-Kansas State line. This report includes three map sheets showing (1) bedrock altitude at the base of the alluvium of the lower Arkansas Valley; (2) estimated spring-to-spring and fall-to-fall changes in water-table altitude between 2002, 2008, and 2015; and (3) estimated saturated thickness in the alluvium during spring and fall of 2002, 2008, and 2015, and thickness of the alluvium in the lower Arkansas Valley. Water-level changes were analyzed by geospatial interpolation methods. Available data included all water-level measurements made between January 1, 2001, and December 31, 2015; however, only data from fall and spring of 2002, 2008, and 2015 are mapped in this report. To account for the effect of John Martin Reservoir in Bent County, Colorado, lake levels at the reservoir were assigned to points along the approximate shoreline and were included in the water-level dataset. After combining the water-level measurements and lake levels, inverse distance weighting was used to interpolate between points and calculate the altitude of the water table for fall and spring of each year for comparisons. Saturated thickness was calculated by subtracting the bedrock surface from the water-table surface. Thickness of the alluvium was calculated by subtracting the bedrock surface from land surface using a digital elevation model. In order to analyze the response of the alluvium to varying environmental and anthropogenic conditions, the percentage of area of the lower Arkansas Valley showing an absolute change of 3 feet or less was calculated for each of the six water-table altitude change maps. For fall water-table altitude change maps, the periods between 2002 and 2008, 2008 and 2015, and 2002 and 2015 showed that 86.5 percent, 85.2 percent, and 66.3 percent of the study area, respectively, showed a net change of 3 feet or less. In the spring water-table altitude change maps these periods showed a net change of 3 feet or less in 94.4 percent, 96.1 percent, and 90.2 percent of the study area, respectively. While the estimated change in water-table altitude was slightly greater and more variable in fall-to-fall comparisons, these high percentages of area with relatively small net changes indicated that, at least in comparisons of the years presented, there was not a large amount of fluctuation in the altitude of the water table. The saturated thickness in the lower Arkansas Valley was between 25 and 50 feet in 34.4 to 35.9 percent of the study area, depending on the season and year. Between 30.2 and 35.6 percent of the area showed saturated thicknesses between 0 and 25 feet. Less than 1 percent of the area showed a saturated thickness greater than 200 feet in all mapped seasons and years.

Colorado↗

Hydrologic unit maps

A set of maps depicting approved boundaries of, and numerical codes for, river-basin units of the United States has been developed by the U.S . Geological Survey. These 'Hydrologic Unit Maps' are four-color maps that present information on drainage, culture, hydrography, and hydrologic boundaries and codes of (1) the 21 major water-resources regions and the 222 subregions designated by the U.S . Water Resources Council, (2) the 352 accounting units of the U.S. Geological Survey's National Water Data Network, and (3) the 2,149 cataloging units of the U.S . Geological Survey's 'Catalog of information on Water Data:' The maps are plotted on the Geological Survey State base-map series at a scale of 1 :500,000 and, except for Alaska, depict hydrologic unit boundaries for all drainage basins greater than 700 square miles (1,813 square kilometers). A complete list of all the hydrologic units, along with their drainage areas, their names, and the names of the States or outlying areas in which they reside, is contained in the report. These maps and associated codes provide a standardized base for use by water-resources organizations in locating, storing, retrieving, and exchanging hydrologic data, in indexing and inventorying hydrologic data and information, in cataloging water-data acquisition activities, and in a variety of other applications. Because the maps have undergone extensive review by all principal Federal, regional, and State water-resource agencies, they are widely accepted for use in planning and describing water-use and related land-use activities, and in geographically organizing hydrologic data . Examples of these uses are given in the report . The hydrologic unit codes shown on the maps have been approved as a Federal Information Processing Standard for use by the Federal establishment.

Water Supply Paper↗

Unrecorded tundra fires of the Arctic Slope, Alaska USA

Few fires are known to have burned the tundra of the Arctic Slope north of the Brooks Range in Alaska, USA. A total of 90 fires between 1969 and 2022 are known. Because fire has been rare, old burns can be detected by the traces of thermokarst and distinct vegetation they leave in otherwise uniform tundra, which are visible in aerial photograph archives. Several prehistoric tundra burns have been found in this way. Detection of tundra fires in this sparsely populated and remote area has been historically inconsistent and opportunistic, relying on reports by aircraft pilots. Fire reports have been logged into an administrative database which, out of necessity, has been used to scientifically evaluate changes in the fire regime. To improve the consistency of the record, we completed a systematic search of Landsat Collection 2 for the Brooks Range Foothills ecoregion over the period 1972–2022. We found 57 unrecorded tundra burns, about 41% of the total, which now numbers 138. Only 15% and 33% of all fires appear in MODIS and VIIRS satellite-borne thermal anomaly products, respectively. The fire frequency in the first 37 years of the record is 0.89 y −1 for natural ignitions that spread ≥10 ha. Frequency in the last 13 years is 2.5 y −1 , indicating a nearly three-fold increase in fire frequency.

Alaska↗

Pen rearing and imprinting of fall Chinook salmon. Annual report 1989

The goal of this project is to compare net-pen rearing methods to traditional hatchery methods of rearing upriver bright fall chinook salmon (Oncorhvnchus tshawvtscha). Fish were reared at several densities in net pens at three Columbia River backwater sites during 1984-1987, and in a barrier net at one site during 1984-1986; methods included both fed and unfed treatments. The purpose of this report is to summarize the results obtained from the unfed treatments and the current return of adults from all fed treatments and the barrier net. Zooplankton were the primary food item of unfed fish. Fish reared in net pens utilized insects colonizing the nets as an additional food source, whereas those reared in the barrier net did not. Growth and production of fish reared in the unfed treatments were low. Instantaneous growth rates of unfed fish were much lower than those of the fed treatments and hatchery controls except when zooplankton densities were high and chironomid larvae were important in the diet of unfed fish reared in pens. Only fish in the barrier net treatment resulted in consistent net gains in growth and production over the rearing periods. Adult returns of fish from all fed and unfed treatments are lower than those of control fish reared at the hatchery. Returns appear to be inversely related to rearing density. Even though adult returns are lower than those of traditional hatchery methods, a cost-benefit analysis, as return data becomes more complete, may prove these methods to be an economical means of expanding current hatchery production, particularly if "thinning" releases were used.

Report↗

Gravity anomaly and interpretation map of the Chignik and Sutwik Island quadrangles, Alaska

The gravity field of the Chignik and Sutwik Island quadrangles near the center of the Alaska Peninsula represents a complex series of transitions between probable continental crust on the north, probable oceanic crust on the south, sedimentary basins on each side of the peninsula, and a central structural high and volcanic arc. The resulting gravity field may be generalized as a central southwest- to northeast-trending gravity high bordered on both sides by flanking gravity lows over sedimentary basins underlying the lowlands and continental shelf. All three gravitational features show discontinuities and magnitude variations that reflect the complex geologic setting. Data concerning this complex gravity field have accumulated slowly and intermittently since an initial measurement was made at Port Heiden more than 25 years go (Thiel and others, 1958, 1959). A few reconnaissance measurements by R. V. Allen and an offshore traverse conducted by the U.S. Coast and Geodetic Survey R/V Surveyor were made in the early 1960's (Barnes and others, 1966; Barnes, 1967). At about the same time, Gulf Oil Corp. contracted for a relatively detailed survey of the lowlands on the north shore of the peninsula; the map prepared from this survey is now available (Gulf Oil Corp., Port Moller Development Contract Report, available at U.S. Geological Survey, Anchorage, Alaska). In the early 1970's, a few new land measurements were made by P. L. Dobey, of the Alaska Division of Geological and Geophysical Surveys, and an offshore traverse was completed by the R/V C. Greene on contract to the U.S. Geological Survey (Fisher, 1979, and M. A. Fisher, written commun., 1977). The most recent measurements, the basis for this map, were made by M. E. Yount, D. L. Detra, D. R. Jefferis, and J. E. Case during the mineral assessment of the two quadrangles. D. F. Barnes, R. L. Morin, D. R. Jefferis, and R. F. Sikora have shared in the data compilation. Geologic background for the text was provided by R. L. Detterman, T. P. Miller, E. Young, and F. H. Wilson (1979, 1981).

Alaska↗

Progress report: chemical character of surface waters in the Devils Lake Basin, North Dakota

Devils Lake in northeastern North Dakota was at one time the most popular summer resort in the state. With decline in lake level the lake has become a shallow body pf vary saline water, which scenic value and recreational appeal completely destroyed. Under the Missouri River development program, it is proposed to restore the lake level to an altitude of 1,425 feet by diversion of Missouri River water. The chemical character of the water in Devils Lake and in other surface bodies in Devils Lake Basin is determined from the analyses of 95 samples. The physical and chemical properties of lake bed deposits are also shown. Lake water in the basin vary considerable in both concentration and composition, ranging from fresh bicarbonate waters of 300 parts per million dissolved solids to sulfate waters of over 100,000 parts per million of soluble salts. Twenty-four samples indicates the chemical character of water in the Red River of the North and its tributaries. The probable concentration of dissolved solids in water of Devils Lake at altitude 1,425 feet has been estimated as ranging from 3,000 to 7,600 parts per million. Final concentration will largely depend upon the percentage of deposited salts reentering solution and the quality of the inflow water. The possible effects of lake effluents on downstream developments, with particular reference to sanitation and pollution problems, are also discussed in this report.

North Dakota↗