Sample records for western interior core

  1. Time series measurements of transient tracers and tracer-derived transport in the Deep Western Boundary Current between the Labrador Sea and the subtropical Atlantic Ocean at Line W

    NASA Astrophysics Data System (ADS)

    Smith, John N.; Smethie, William M.; Yashayev, Igor; Curry, Ruth; Azetsu-Scott, Kumiko

    2016-11-01

    Time series measurements of the nuclear fuel reprocessing tracer 129I and the gas ventilation tracer CFC-11 were undertaken on the AR7W section in the Labrador Sea (1997-2014) and on Line W (2004-2014), located over the US continental slope off Cape Cod, to determine advection and mixing time scales for the transport of Denmark Strait Overflow Water (DSOW) within the Deep Western Boundary Current (DWBC). Tracer measurements were also conducted in 2010 over the continental rise southeast of Bermuda to intercept the equatorward flow of DSOW by interior pathways. The Labrador Sea tracer and hydrographic time series data were used as input functions in a boundary current model that employs transit time distributions to simulate the effects of mixing and advection on downstream tracer distributions. Model simulations of tracer levels in the boundary current core and adjacent interior (shoulder) region with which mixing occurs were compared with the Line W time series measurements to determine boundary current model parameters. These results indicate that DSOW is transported from the Labrador Sea to Line W via the DWBC on a time scale of 5-6 years corresponding to a mean flow velocity of 2.7 cm/s while mixing between the core and interior regions occurs with a time constant of 2.6 years. A tracer section over the southern flank of the Bermuda rise indicates that the flow of DSOW that separated from the DWBC had undergone transport through interior pathways on a time scale of 9 years with a mixing time constant of 4 years.

  2. Interior pathways of the North Atlantic meridional overturning circulation.

    PubMed

    Bower, Amy S; Lozier, M Susan; Gary, Stefan F; Böning, Claus W

    2009-05-14

    To understand how our global climate will change in response to natural and anthropogenic forcing, it is essential to determine how quickly and by what pathways climate change signals are transported throughout the global ocean, a vast reservoir for heat and carbon dioxide. Labrador Sea Water (LSW), formed by open ocean convection in the subpolar North Atlantic, is a particularly sensitive indicator of climate change on interannual to decadal timescales. Hydrographic observations made anywhere along the western boundary of the North Atlantic reveal a core of LSW at intermediate depths advected southward within the Deep Western Boundary Current (DWBC). These observations have led to the widely held view that the DWBC is the dominant pathway for the export of LSW from its formation site in the northern North Atlantic towards the Equator. Here we show that most of the recently ventilated LSW entering the subtropics follows interior, not DWBC, pathways. The interior pathways are revealed by trajectories of subsurface RAFOS floats released during the period 2003-2005 that recorded once-daily temperature, pressure and acoustically determined position for two years, and by model-simulated 'e-floats' released in the subpolar DWBC. The evidence points to a few specific locations around the Grand Banks where LSW is most often injected into the interior. These results have implications for deep ocean ventilation and suggest that the interior subtropical gyre should not be ignored when considering the Atlantic meridional overturning circulation.

  3. Water-mass evolution in the Cretaceous Western Interior Seaway of North America and equatorial Atlantic

    NASA Astrophysics Data System (ADS)

    Eldrett, James S.; Dodsworth, Paul; Bergman, Steven C.; Wright, Milly; Minisini, Daniel

    2017-07-01

    The Late Cretaceous Epoch was characterized by major global perturbations in the carbon cycle, the most prominent occurring near the Cenomanian-Turonian (CT) transition marked by Oceanic Anoxic Event 2 (OAE-2) at 94.9-93.7 Ma. The Cretaceous Western Interior Seaway (KWIS) was one of several epicontinental seas in which a complex water-mass evolution was recorded in widespread sedimentary successions. This contribution integrates new data on the main components of organic matter, geochemistry, and stable isotopes along a north-south transect from the KWIS to the equatorial western Atlantic and Southern Ocean. In particular, cored sedimentary rocks from the Eagle Ford Group of west Texas (˜ 90-98 Ma) demonstrate subtle temporal and spatial variations in palaeoenvironmental conditions and provide an important geographic constraint for interpreting water-mass evolution. High-latitude (boreal-austral), equatorial Atlantic Tethyan and locally sourced Western Interior Seaway water masses are distinguished by distinct palynological assemblages and geochemical signatures. The northward migration of an equatorial Atlantic Tethyan water mass into the KWIS occurred during the early-middle Cenomanian (98-95 Ma) followed by a major re-organization during the latest Cenomanian-Turonian (95-94 Ma) as a full connection with a northerly boreal water mass was established during peak transgression. This oceanographic change promoted de-stratification of the water column and improved oxygenation throughout the KWIS and as far south as the Demerara Rise off Suriname. In addition, the recorded decline in redox-sensitive trace metals during the onset of OAE-2 likely reflects a genuine oxygenation event related to open water-mass exchange and may have been complicated by variable contribution of organic matter from different sources (e.g. refractory/terrigenous material), requiring further investigation.

  4. The Boquillas Formation of the Big Bend National Park, Texas, USA, a reference Cenomanian through Santonian (Upper Cretaceous) carbonate succession at the southern end of the Western Interior Seaway

    NASA Astrophysics Data System (ADS)

    Cooper, Dee Ann; Cooper, Roger W.; Stevens, James B.; Stevens, M. S.; Cobban, William A.; Walaszczyk, Ireneusz

    2017-12-01

    The upper lower Cenomanian through middle Santonian (Upper Cretaceous) of the Boquillas Formation in the Big Bend Region of Trans-Pecos Texas consists of a marine carbonate succession deposited at the southern end of the Western Interior Seaway. The Boquillas Formation, subdivided into the lower, c. 78 m thick limestone-shale Ernst Member, and the upper, c. 132 m thick limestone/chalk/marl San Vicente Member, was deposited in a shallow shelf open marine environment at the junction between the Western Interior Seaway and the western margins of the Tethys Basin. Biogeographically, the area was closely tied with the southern Western Interior Seaway. The richly fossiliferous upper Turonian, Coniacian and lower Santonian parts of the Boquillas Formation are particularly promising for multistratigraphic studies.

  5. INTERIOR VIEW, WESTERN STOREROOM LOOKING WEST. THE OPENING TO THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW, WESTERN STOREROOM LOOKING WEST. THE OPENING TO THE LEFT OF THE RELIEVING ARCH CONNECTS TO A CORRIDOR LEADING TO THE OFFICE. THE CANTED WALL OF THIS CORRIDOR MARKS THE INTERIOR OF ONE OF THE THREE-SIDED WINDOW BAYS OF THE ORIGINAL HOUSE - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

  6. The Inland Penetration of Atmospheric Rivers over Western North America: A Lagrangian Analysis

    NASA Astrophysics Data System (ADS)

    Rutz, J. J.; Steenburgh, W. J.; Ralph, F. M.

    2014-12-01

    Although atmospheric rivers (ARs) typically weaken following landfall, those that penetrate inland can contribute to heavy precipitation and high-impact weather within the interior of western North America. In this paper, we examine the evolution of ARs over western North America using trajectories released at 950 and 700 hPa within cool-season ARs along the Pacific coast. These trajectories are classified as coastal decaying, inland penetrating, or interior penetrating based on whether they remain within an AR upon reaching selected transects over western North America. Interior-penetrating AR trajectories most frequently make landfall along the Oregon coast, but the greatest fraction of landfalling AR trajectories that eventually penetrate into the interior is found along the Baja Peninsula. In contrast, interior-penetrating trajectories rarely traverse the southern "high" Sierra. At landfall, interior-penetrating trajectories are associated with a more amplified flow pattern, more southwesterly (vs. westerly) flow along the Pacific coast, and larger water vapor transport (qu). The larger initial qu of interior-penetrating trajectories is due primarily to larger initial water vapor (q) and wind speed (u) for those initiated at 950 and 700 hPa, respectively. Inland- and interior-penetrating AR trajectories maintain large qu over the interior due partially to increases in u that offset decreases in q, particularly in the vicinity of topographical barriers. Therefore, synoptic conditions and trajectory pathways favoring larger initial qu at the coast, limited water vapor depletion by orographic precipitation, and increases in u over the interior are keys to differentiating interior-penetrating from coastal-decaying AR trajectories.

  7. 31. INTERIOR VIEW OF PLATFORM ALONG WESTERN WALL OF CLEAN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    31. INTERIOR VIEW OF PLATFORM ALONG WESTERN WALL OF CLEAN STEEL PRODUCTION BUILDING. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  8. Drought-triggered western spruce budworm outbreaks in the Interior Pacific Northwest: A multi-century dendrochronological record

    Treesearch

    A. Flower; D. G. Gavin; E. K. Heyerdahl; R. A. Parsons; G. M. Cohn

    2014-01-01

    Douglas-fir forests in the interior Pacific Northwest are subject to sporadic outbreaks of the western spruce budworm, a species widely recognized as the most destructive defoliator in western North America. Outbreaks of the western spruce budworm often occur synchronously over broad regions and lead to widespread loss of leaf area and decrease in growth rates in...

  9. INTERIOR FROM WESTERN SECTION, THROUGH CENTRAL SECTION, TO EASTERN SECTION, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR FROM WESTERN SECTION, THROUGH CENTRAL SECTION, TO EASTERN SECTION, VIEW FACING NORTHEAST. - Naval Air Station Barbers Point, Aircraft Storehouse, Between Midway & Card Streets at Enterprise Avenue intersection, Ewa, Honolulu County, HI

  10. 5. INTERIOR, STORAGE AREA AT WESTERN END, FROM SOUTH OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. INTERIOR, STORAGE AREA AT WESTERN END, FROM SOUTH OF LOADING DOCK WELL, LOOKING NORTH. - Oakland Naval Supply Center, Coffee Roasting Plant, East of Fourth Street, between J & K, Oakland, Alameda County, CA

  11. Selected hydrologic data for the Bonneville Salt Flats and Pilot Valley, western Utah, 1991-93

    USGS Publications Warehouse

    Mason, James L.; Brothers, William C.; Gerner, Linda J.; Muir, Pamela S.

    1995-01-01

    This report contains hydrologic data collected during 1991-93 in the Bonneville Salt Flats and Pilot Valley study area of western Utah. These data were collected in cooperation with the U.S. Department of the Interior, Bureau of Land Management, as part of a study to investigate possible salt loss from the Bonneville Salt Flats. The Bonneville Salt Flats and adjacent Pilot Valley are located in the western part of the Great Salt Lake Desert in Utah, near the Nevada border. The Bonneville Salt Flats playa has a thick, perennial salt crust and the Pilot Valley playa has a thin, ephemeral salt crust. Well-completion data, including well depth and screened intervals, are presented in this report for selected shallow and deep monitoring wells. Water-level measurements are reported with corresponding specfic-gravity and temperature measurements. Results of chemical analyses are reported for brine collected from wells and pore fluids extracted from cores.

  12. Spatial Variability of Climate Signatures Recorded in an Array of Shallow Firn Cores from the Western Greenland Percolation Zone

    NASA Astrophysics Data System (ADS)

    Thundercloud, Z. R.; Osterberg, E. C.; Ferris, D. G.; Graeter, K.; Lewis, G.; Hawley, R. L.; Marshall, H. P.

    2016-12-01

    Greenland ice cores provide seasonally to annually resolved proxy records of past temperature, accumulation and atmospheric circulation. Most Greenland ice cores have been collected from the dry snow zone at elevations greater than 2500 m to produce records of North Atlantic paleoclimate over the last full glacial cycle. Ice cores collected from more costal regions, however, provide the opportunity to develop regional-scale records of climate conditions along ice sheet margins where recent temperature and precipitation changes have been larger than those in the ice sheet interior. These cores are more readily comparable to lake sediment and landscape (i.e. moraine) records from the ice sheet margin, and are potentially more sensitive to sea-ice variability due to the proximity to the coast. Here we present major ion and stable isotope records from an array of firn cores (40-55 year records) collected in the western Greenland percolation zone, and assess the spatial variability of ice core statistical relationships with the North Atlantic Oscillation (NAO) and Baffin Bay sea ice extent. Seven cores were collected from elevations of 2100-2500 m along a 400-km segment of the ice sheet from Dye-2 to Milcent as part of the Greenland Traverse for Accumulation and Climate Studies (GreenTrACS) project from May-June 2016. They were sampled by a continuous melter system at Dartmouth College, and analyzed using Dionex ion chromatographs and a Picarro L2130-i laser ring-down spectrometer. We focus on the signature of the NAO and Baffin Bay sea ice extent in the sea-salt, dust, deuterium excess (d-excess), and methanesulfonic acid (MSA) firn core records, and assess the special variability of these climate-ice core relationships across the study area. Climate reanalysis data indicate that NAO-ice core correlations should be stronger at lower elevation in the percolation zone than high in the dry snow zone. Our results will provide valuable insight into the sensitivity of Greenland ice core paleoclimate reconstructions to the specific ice core location, and thereby aid in site selection for deeper ice cores that could span the Holocene.

  13. Facile fabrication of core-in-shell particles by the slow removal of the core and its use in the encapsulation of metal nanoparticles.

    PubMed

    Choi, Won San; Koo, Hye Young; Kim, Dong-Yu

    2008-05-06

    Core-in-shell particles with controllable core size have been fabricated from core-shell particles by means of the controlled core-dissolution method. These cores in inorganic shells were employed as scaffolds for the synthesis of metal nanoparticles. After dissolution of the cores, metal nanoparticles embedded in cores were encapsulated into the interior of shell, without any damage or change. This article describes a very simple method for deriving core-in-shell particles with controllable core size and encapsulation of nanoparticles into the interior of shell.

  14. INTERIOR OF WESTERN SECTION, SHOWING WALL OF COLD STORAGE ROOM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF WESTERN SECTION, SHOWING WALL OF COLD STORAGE ROOM (IN BAYS 32 TO 34) AND ROLLING DOORS AT WEST END, VIEW FACING SOUTH-SOUTHWEST. - Naval Air Station Barbers Point, Aircraft Storehouse, Between Midway & Card Streets at Enterprise Avenue intersection, Ewa, Honolulu County, HI

  15. 11. BUILDING 332, INTERIOR, WESTERN STOREROOM, FROM FIRE DOOR IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. BUILDING 332, INTERIOR, WESTERN STOREROOM, FROM FIRE DOOR IN EAST WALL, LOOKING WEST, WITH ENCLOSED OFFICE AREA (PHOTOS AA-7 &-8) BEYOND WALL ON RIGHT. - Oakland Naval Supply Center, Dry Provisions Storehouses, Between Third & Fourth Streets, Between G & L Street, Oakland, Alameda County, CA

  16. Late Quaternary stratigraphy and sedimentation patterns in the western Arctic Ocean

    USGS Publications Warehouse

    Polyak, L.; Bischof, J.; Ortiz, J.D.; Darby, D.A.; Channell, J.E.T.; Xuan, C.; Kaufman, D.S.; Lovlie, R.; Schneider, D.A.; Eberl, D.D.; Adler, R.E.; Council, E.A.

    2009-01-01

    Sediment cores from the western Arctic Ocean obtained on the 2005 HOTRAX and some earlier expeditions have been analyzed to develop a stratigraphic correlation from the Alaskan Chukchi margin to the Northwind and Mendeleev-Alpha ridges. The correlation was primarily based on terrigenous sediment composition that is not affected by diagenetic processes as strongly as the biogenic component, and paleomagnetic inclination records. Chronostratigraphic control was provided by 14C dating and amino-acid racemization ages, as well as correlation to earlier established Arctic Ocean stratigraphies. Distribution of sedimentary units across the western Arctic indicates that sedimentation rates decrease from tens of centimeters per kyr on the Alaskan margin to a few centimeters on the southern ends of Northwind and Mendeleev ridges and just a few millimeters on the ridges in the interior of the Amerasia basin. This sedimentation pattern suggests that Late Quaternary sediment transport and deposition, except for turbidites at the basin bottom, were generally controlled by ice concentration (and thus melt-out rate) and transportation distance from sources, with local variances related to subsurface currents. In the long term, most sediment was probably delivered to the core sites by icebergs during glacial periods, with a significant contribution from sea ice. During glacial maxima very fine-grained sediment was deposited with sedimentation rates greatly reduced away from the margins to a hiatus of several kyr duration as shown for the Last Glacial Maximum. This sedimentary environment was possibly related to a very solid ice cover and reduced melt-out over a large part of the western Arctic Ocean.

  17. Merging altimeter data with Argo profiles to improve observation of tropical Pacific thermocline circulation and ENSO

    NASA Astrophysics Data System (ADS)

    Zhang, D.; Lee, T.; Wang, F.; McPhaden, M. J.; Kessler, W. S.

    2016-12-01

    Meridional thermocline currents play an important role in the recharge and discharge of tropical Pacific warm water during the development and transition of ENSO cycles. Previous analyses have shown large variations of the equatorward meridional thermocline convergence/divergence on ENSO and decadal time scales in the interior ocean. The total convergence/divergence is however unknown due to the lack of long term observation in the western boundary currents. Numerical modelling studies suggested a tendency of compensation between the interior and western boundary currents, but the exact compensation is model dependent. While Argo floats provide reasonable data coverage in the interior ocean, few floats are in the western boundary currents. Recent multi-mission satellite altimeter data and advanced processing techniques have resulted in higher resolution sea surface height anomaly (SSHA) products with better accuracy closer to the coasts. This study utilizes the statistical relationship between Argo dynamic height profiles and altimeter SSHA to calculate geostrophic thermocline currents in both the interior ocean and the western boundary of the tropical Pacific. The derived thermocline currents in the western boundary are validated by a 3.5-year moored Acoustic Doppler Current Profiler (ADCP) measurement in the Mindanao Current and by a series of glider surveys (Davis et al. 2012) in the Solomon Sea. The meridional transport timeseries of the interior and western boundary currents in the thermocline show different lead-lag relationships to the Nino 3.4 index. Results will be discussed in the context of recent 2014-2015 El Nino development and the potential contribution to the Tropical Pacific Observing System (TPOS).

  18. 77 FR 68826 - Notice of Inventory Completion: U.S. Department of the Interior, Bureau of Indian Affairs...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-16

    ... DEPARTMENT OF THE INTERIOR National Park Service [NPS-WASO-NAGPRA-11440; 2200-1100-665] Notice of.... Department of the Interior, National Park Service, Western Archeological and Conservation Center, Tucson, AZ AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The U.S. Department of the Interior...

  19. Contact allergy to finished woods in furniture and furnishings: a small allergic contact dermatitis epidemic to western red cedar in sauna interior decoration.

    PubMed

    Huilaja, L; Kubin, M E; Riekki, R

    2016-01-01

    Allergic contact dermatitis caused by wood dust remains uncommon and most cases are occupational. Contact allergy to finished wooden products is even more rare and only few cases of contact dermatitis to wooden furnishings and furniture are described. During 2012-2014 surprisingly many patients with dermatitis associated to sauna baths were referred to our clinic. We report three novel cases with allergic contact dermatitis to western red cedar due to exposure during sauna baths. Three cases of non-occupational contact dermatitis to western red cedar were confirmed by patch testing. Allergic contact dermatitis to interior decoration or furniture is a rarity, but can be induced by novel exposures, like western red cedar in sauna interior decoration. © 2015 European Academy of Dermatology and Venereology.

  20. Empirical models of Jupiter's interior from Juno data. Moment of inertia and tidal Love number k2

    NASA Astrophysics Data System (ADS)

    Ni, Dongdong

    2018-05-01

    Context. The Juno spacecraft has significantly improved the accuracy of gravitational harmonic coefficients J4, J6 and J8 during its first two perijoves. However, there are still differences in the interior model predictions of core mass and envelope metallicity because of the uncertainties in the hydrogen-helium equations of state. New theoretical approaches or observational data are hence required in order to further constrain the interior models of Jupiter. A well constrained interior model of Jupiter is helpful for understanding not only the dynamic flows in the interior, but also the formation history of giant planets. Aims: We present the radial density profiles of Jupiter fitted to the Juno gravity field observations. Also, we aim to investigate our ability to constrain the core properties of Jupiter using its moment of inertia and tidal Love number k2 which could be accessible by the Juno spacecraft. Methods: In this work, the radial density profile was constrained by the Juno gravity field data within the empirical two-layer model in which the equations of state are not needed as an input model parameter. Different two-layer models are constructed in terms of core properties. The dependence of the calculated moment of inertia and tidal Love number k2 on the core properties was investigated in order to discern their abilities to further constrain the internal structure of Jupiter. Results: The calculated normalized moment of inertia (NMOI) ranges from 0.2749 to 0.2762, in reasonable agreement with the other predictions. There is a good correlation between the NMOI value and the core properties including masses and radii. Therefore, measurements of NMOI by Juno can be used to constrain both the core mass and size of Jupiter's two-layer interior models. For the tidal Love number k2, the degeneracy of k2 is found and analyzed within the two-layer interior model. In spite of this, measurements of k2 can still be used to further constrain the core mass and size of Jupiter's two-layer interior models.

  1. Armillaria altimontana, a new species from the western interior of North America

    Treesearch

    Nicholas J. Brazee; Beatriz Ortiz-Santana; Mark T. Banik; Daniel L. Lindner

    2012-01-01

    Armillaria altimontana, previously considered North American biological species (NABS) X, is described as new. To date, it appears that A. altimontana prefers higher-elevation, mesic sites within the dry, conifer forest zone of western interior North America. This species has been found on hardwoods and conifers and is associated...

  2. 78 FR 3446 - Notice of Public Meeting; Western Montana Resource Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-16

    ... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLMTB07900 09 L10100000 PH0000 LXAMANMS0000] Notice of Public Meeting; Western Montana Resource Advisory Council AGENCY: Bureau of Land Management... Management Act and the Federal Advisory Committee Act of 1972, the U.S. Department of the Interior, Bureau of...

  3. 77 FR 30550 - Notice of Public Meeting; Western Montana Resource Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-23

    ... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLMTB07900 09 L10100000 PH0000 LXAMANMS0000] Notice of Public Meeting; Western Montana Resource Advisory Council AGENCY: Bureau of Land Management... Management Act and the Federal Advisory Committee Act of 1972, the U.S. Department of the Interior, Bureau of...

  4. 78 FR 45955 - Notice of Public Meeting; Western Montana Resource Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-30

    ... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLMTB07900 09 L10100000 PH0000 LXAMANMS0000] Notice of Public Meeting; Western Montana Resource Advisory Council AGENCY: Bureau of Land Management... Management Act and the Federal Advisory Committee Act of 1972, the U.S. Department of the Interior, Bureau of...

  5. 78 FR 42970 - Notice of Intent To Prepare a Resource Management Plan for the Bering Sea-Western Interior...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-18

    ...] Notice of Intent To Prepare a Resource Management Plan for the Bering Sea-Western Interior Planning Area... Management (BLM) Anchorage Field Office, Anchorage, Alaska, intends to prepare a Resource Management Plan... properties, visual resources, wildland fire management, lands with wilderness characteristics, forestry...

  6. 76 FR 27342 - Central Utah Project Completion Act; Notice of Intent To Accept Proposals, Select a Potential...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-11

    ... DEPARTMENT OF THE INTERIOR Central Utah Project Completion Act; Notice of Intent To Accept... Interior. ACTION: Notice. SUMMARY: Current Federal policy encourages non-Federal development of... Interior (Interior), in consultation with the Department of Energy, Western Area Power Administration...

  7. Integrated management of timber and deer: interior forests of western North America.

    Treesearch

    H.M. Armleder; D.A. Leckenby; D.J. Freddy; L.L. Hicks

    1989-01-01

    Timber and deer managers have struggled through years of increasing demands and growing conflicts in the interior of Western North America. Integrated management, supported by a sound research data base and effectively communicated to all users, is presented as the only viable approach to an increasingly complex resource future. Two examples of tools recently designed...

  8. Preliminary Results on Lunar Interior Properties from the GRAIL Mission

    NASA Technical Reports Server (NTRS)

    Williams, James G.; Konopliv, Alexander S.; Asmar, Sami W.; Lemoine, H. Jay; Melosh, H. Jay; Neumann, Gregory A.; Phillips, Roger J.; Smith, David E.; Solomon, Sean C.; Watkins, Michael M.; hide

    2013-01-01

    The Gravity Recovery and Interior Laboratory (GRAIL) mission has provided lunar gravity with unprecedented accuracy and resolution. GRAIL has produced a high-resolution map of the lunar gravity field while also determining tidal response. We present the latest gravity field solution and its preliminary implications for the Moon's interior structure, exploring properties such as the mean density, moment of inertia of the solid Moon, and tidal potential Love number k2. Lunar structure includes a thin crust, a deep mantle, a fluid core, and a suspected solid inner core. An accurate Love number mainly improves knowledge of the fluid core and deep mantle. In the future GRAIL will search for evidence of tidal dissipation and a solid inner core.

  9. A wet, heterogeneous lunar interior: Lower mantle and core dynamo evolution

    NASA Astrophysics Data System (ADS)

    Evans, A. J.; Zuber, M. T.; Weiss, B. P.; Tikoo, S. M.

    2014-05-01

    While recent analyses of lunar samples indicate the Moon had a core dynamo from at least 4.2-3.56 Ga, mantle convection models of the Moon yield inadequate heat flux at the core-mantle boundary to sustain thermal core convection for such a long time. Past investigations of lunar dynamos have focused on a generally homogeneous, relatively dry Moon, while an initial compositionally stratified mantle is the expected consequence of a postaccretionary lunar magma ocean. Furthermore, recent re-examination of Apollo samples and geophysical data suggests that the Moon contains at least some regions with high water content. Using a finite element model, we investigate the possible consequences of a heterogeneously wet, compositionally stratified interior for the evolution of the Moon. We find that a postoverturn model of mantle cumulates could result in a core heat flux sufficiently high to sustain a dynamo through 2.5 Ga and a maximum surface, dipolar magnetic field strength of less than 1 μT for a 350-km core and near ˜2 μT for a 450-km core. We find that if water was transported or retained preferentially in the deep interior, it would have played a significant role in transporting heat out of the deep interior and reducing the lower mantle temperature. Thus, water, if enriched in the lower mantle, could have influenced core dynamo timing by over 1.0 Gyr and enhanced the vigor of a lunar core dynamo. Our results demonstrate the plausibility of a convective lunar core dynamo even beyond the period currently indicated by the Apollo samples.

  10. Climate change in grasslands, shrublands, and deserts of the interior American West: a review and needs assessment

    Treesearch

    Deborah M. Finch

    2012-01-01

    Recent research and species distribution modeling predict large changes in the distributions of species and vegetation types in the western interior of the United States in response to climate change. This volume reviews existing climate models that predict species and vegetation changes in the western United States, and it synthesizes knowledge about climate change...

  11. Improvements on the interior structure of Mercury expected from geodesy measurements

    NASA Astrophysics Data System (ADS)

    Rivoldini, A.; van Hoolst, T.; Verhoeven, O.

    2008-09-01

    ABSTRACT We assess the improvements on the interior structure of Mercury provided by expected data from geodesy experiments to be performed with the MESSENGER and BepiColombo orbiters. The observation of obliquity will allow estimating the moment of inertia, whereas measurements of libration will determine the moment of inertia of the silicate shell (mantle and crust). Tidal measurements will constrain the Love numbers that characterize the response of Mercury to the solar tidal forcing. Here, we construct depth-dependent interior structure models of Mercury for several plausible chemical compositions of the core and of the mantle using recent data on core and mantle materials. In particular we study the core structure for different mantle mineralogies and two different temperature profiles. We investigate the influence of the core light element concentration, temperature, and melting law on core state and inner core size. We compute libration amplitude, obliquity, tidal deformation, and tidal changes in the external potential for our models.

  12. Properties of the Lunar Interior: Preliminary Results from the GRAIL Mission

    NASA Technical Reports Server (NTRS)

    Williams, James G.; Konopliv, Alexander S.; Asmar, Sami W.; Lemoine, Frank G.; Melosh, H. Jay; Neumann, Gregory A.; Phillips, Roger J.; Smith, David E.; Solomon, Sean C.; Watkins, Michael M.; hide

    2013-01-01

    The Gravity Recovery and Interior Laboratory (GRAIL) mission [1] has provided lunar gravity with unprecedented accuracy and resolution. GRAIL has produced a high-resolution map of the lunar gravity field [2,3] while also determining tidal response. We present the latest gravity field solution and its preliminary implications for the Moon's interior structure, exploring properties such as the mean density, moment of inertia of the solid Moon, and tidal potential Love number k(sub 2). Lunar structure includes a thin crust, a thick mantle layer, a fluid outer core, and a suspected solid inner core. An accurate Love number mainly improves knowledge of the fluid core and deep mantle. In the future, we will search for evidence of tidal dissipation and a solid inner core using GRAIL data.

  13. 76 FR 36149 - Notice of Inventory Completion: Western Michigan University, Department of Anthropology...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-21

    ...: Western Michigan University, Department of Anthropology, Kalamazoo, MI AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: Western Michigan University, Department of Anthropology, has completed... contact the Western Michigan University, Department of Anthropology. Disposition of the human remains and...

  14. 76 FR 28077 - Notice of Inventory Completion: Western Michigan University, Anthropology Department, Kalamazoo, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-13

    ...: Western Michigan University, Anthropology Department, Kalamazoo, MI AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: Western Michigan University, Department of Anthropology, has completed... contact the Western Michigan University, Department of Anthropology. Disposition of the human remains to...

  15. Molluscan extinction patterns across the Cenomanian-Turonian stage boundary in the western interior of the United States

    USGS Publications Warehouse

    Elder, W.P.

    1989-01-01

    High-resolution stratigraphic analysis of 18 sections spanning the Cenomanian-Turonian Stage boundary in the western interior of the United States has allowed determination of the magnitude and pattern of molluscan extinction and disruption. Composite range data from all sections show that the faunal turnover across the stage boundary occurs in a series of narrow stratigraphic zones, defined by multiple first and last occurrences, separated by intervals displaying little or no taxonomic turnover. Two of the apparent extinction steps (bottom and top of the Neocardioceras juddii Zone) may be intercontinentally developed. The additional steps apparently reflect cyclic changes in water mass and substrate characteristics in the western interior basin produced in response to orbital forcing of climate. The most affected mollusks were those having intercontinental distributions. -Author

  16. Effects of historic forest disturbance on water quality and flow in the Interior Western U.S

    Treesearch

    M. Matyjasik; G. Moisen; C. Combe; T. Hathcock; S. Mitts; M. Hernandez; T. Frescino; T. Schroeder

    2014-01-01

    Water quality and flow is affected my many complex factors in the Interior Western U.S. While many studies focus on individual water parameters response to a limited number of changing conditions, little work looks at long term effects of diverse forest disturbances on a broader array of water quality and flow metrics. The U.S. Forest Service Forest Inventory and...

  17. Insights into Mercury's interior structure from geodesy measurements

    NASA Astrophysics Data System (ADS)

    Rivoldini, A.; Van Hoolst, T.; Trinh, A.

    2013-09-01

    The measurements of the gravitational field of Mercury by MESSENGER [1] and improved measurements of the spin state of Mercury [2] provide important constraints on the interior structure of Mercury. In particular, these data give strong constraints on the radius and density of Mercury's core and on the core's concentration of sulfur if sulfur is the only light element in the core [3]. Although sulfur is ubiquitously invoked as being the principal candidate light element in terrestrial planet's cores its abundance in the core depends on the redox conditions during planetary formation. MESSENGER data from remote sensing of Mercury's surface [4] indicate a high abundance of sulfur and confirm the low abundance in FeO supporting the hypotheses that Mercury formed under reducing conditions [5]. Therefore, substantial amounts of other light elements like for instance silicon could be present together with sulfur inside Mercury's core. Unlike sulfur, which does almost not partition into solid iron under Mercury's core pressure and temperature conditions, silicon partitions virtually equally between solid and liquid iron. Thus, if silicon is the only light element inside the core, the density jump at the inner-core outer-core boundary is significantly smaller if compared to an Fe - FeS core. If both silicon and sulfur are present inside Mercury's core then as a consequence of a large immiscibility region in liquid Fe - Si - S at Mercury's core conditions and for specific concentrations of light elements [6] a thin layer much enriched in sulfur and depleted in silicon could form at the top of the core. In this study we analyze interior structure models with silicon as the only light element in the core and with both silicon and sulfur in the core. Compared to models with Fe - FeS both settings have different mass distributions within their cores and will likely deform differently due to different elastic properties. Consequently their libration and tides will be different. Here we will use the measured 88 day libration amplitude and polar moment of inertia of Mercury in order to constrain the interior structure of both settings and calculate their tides.

  18. Fast core rotation in red-giant stars as revealed by gravity-dominated mixed modes.

    PubMed

    Beck, Paul G; Montalban, Josefina; Kallinger, Thomas; De Ridder, Joris; Aerts, Conny; García, Rafael A; Hekker, Saskia; Dupret, Marc-Antoine; Mosser, Benoit; Eggenberger, Patrick; Stello, Dennis; Elsworth, Yvonne; Frandsen, Søren; Carrier, Fabien; Hillen, Michel; Gruberbauer, Michael; Christensen-Dalsgaard, Jørgen; Miglio, Andrea; Valentini, Marica; Bedding, Timothy R; Kjeldsen, Hans; Girouard, Forrest R; Hall, Jennifer R; Ibrahim, Khadeejah A

    2011-12-07

    When the core hydrogen is exhausted during stellar evolution, the central region of a star contracts and the outer envelope expands and cools, giving rise to a red giant. Convection takes place over much of the star's radius. Conservation of angular momentum requires that the cores of these stars rotate faster than their envelopes; indirect evidence supports this. Information about the angular-momentum distribution is inaccessible to direct observations, but it can be extracted from the effect of rotation on oscillation modes that probe the stellar interior. Here we report an increasing rotation rate from the surface of the star to the stellar core in the interiors of red giants, obtained using the rotational frequency splitting of recently detected 'mixed modes'. By comparison with theoretical stellar models, we conclude that the core must rotate at least ten times faster than the surface. This observational result confirms the theoretical prediction of a steep gradient in the rotation profile towards the deep stellar interior.

  19. 36 CFR 242.22 - Subsistence resource regions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-Kuskokwim Delta Region; (6) Western Interior Region; (7) Seward Peninsula Region; (8) Northwest Arctic Region; (9) Eastern Interior Region; (10) North Slope Region. (b) You may obtain maps delineating the...

  20. Cretaceous-tertiary boundary spherules and Cenozoic microtektites: Similarities and differences

    NASA Technical Reports Server (NTRS)

    Glass, B. P.; Bohor, Bruce F.; Betterton, William J.

    1993-01-01

    Bohor and Betterton pointed out that the K-T spherules can be divided into three groups. Their Type 1 spherules appear to be found in or adjacent to North America, particularly the Western Interior and in Haiti and Mexico. The Type 1 spherules occur in the lower part of the K-T boundary clay below an Ir anomaly. It is the Type 1 spherules which are most similar to microtektites. The discovery of K-T boundary spherules in Beloc, Haiti, and Mimbral, Mexico, with residual tektite-like glass cores supports the hypothesis that the Type 1 spherules are diagenetically altered microtektites. The similarities and differences of the Type 1 K-T boundary spherules to previously described Cenozoic microtektites are discussed.

  1. 50 CFR 100.22 - Subsistence resource regions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Bristol Bay Region; (5) Yukon-Kuskokwim Delta Region; (6) Western Interior Region; (7) Seward Peninsula Region; (8) Northwest Arctic Region; (9) Eastern Interior Region; (10) North Slope Region. (b) You may...

  2. 6. Interior view of tanks on first floor, looking east. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Interior view of tanks on first floor, looking east. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Oil House, 650 feet Southeast of Cliff & Mechanic Streets, Scranton, Lackawanna County, PA

  3. 7. Row of pumps against first floor interior west wall. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Row of pumps against first floor interior west wall. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Oil House, 650 feet Southeast of Cliff & Mechanic Streets, Scranton, Lackawanna County, PA

  4. Antenna cab interior showing equipment rack and fiberglass antenna panels, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Antenna cab interior showing equipment rack and fiberglass antenna panels, looking west. - Western Union Telegraph Company, Jennerstown Relay, Laurel Summit Road off U.S. 30, Laughlintown, Westmoreland County, PA

  5. Antenna cab interior showing equipment rack and fiberglass antenna panels, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Antenna cab interior showing equipment rack and fiberglass antenna panels, looking southeast. - Western Union Telegraph Company, Jennerstown Relay, Laurel Summit Road off U.S. 30, Laughlintown, Westmoreland County, PA

  6. Tracing Carbon Cycling in the Atmosphere and Oceans During the Cretaceous Ocean Anoxic Event 2 (OAE2, 94Ma)

    NASA Astrophysics Data System (ADS)

    Moran, S. A. M.; Boudinot, F. G.; Dildar, N.; Sepúlveda, J.

    2017-12-01

    We present a high-resolution record of compound-specific stable carbon isotope data from short-chain—aquatic algae—and long-chain n-alkanes—terrestrial plants—preserved in sedimentary sequences from the Smokey Hollow #1 (SH1) core in the Grand Staircase Escalante National Monument in southern Utah. The study area covered by SH1 core was situated at the western margin of the Western Interior Seaway during the Cretaceous Ocean Anoxic Event (OAE2, 94Ma.), and was characterized by high sedimentation rates and enhanced preservation of both marine and terrestrial organic matter. Short- and long-chain n-alkanes were isolated and purified from branched and cyclic aliphatic hydrocarbons using an optimized urea adduction protocol, and δ13Cn-alkane was measured using a Thermo MAT253 GC-C-IR-MS. We use the δ13Cn-alkane from aquatic and terrestrial sources to better understand carbon cycle interactions in the oceanic and atmospheric carbon pools across this event. Our results indicate that the δ13C of terrestrial plants experienced a faster and more pronounced positive carbon isotope excursion compared to marine sources. We will discuss how these results can inform models of carbon cycle interactions between the ocean and the atmosphere during greenhouse climates, and how they can be used to trace possible sources of CO2.

  7. Permeability structure of a highly heterogeneous transgressive-marine complex: Tocito Sandstone, New Mexico

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lambert, M.L.; Cole, R.D.

    1996-01-01

    The Tocito Sandstone Member of the Mancos Shale is an Upper Cretaceous shallow-marine sandstone and mudrock complex deposited along the western margin of the Western Interior seaway. The Tocito is a major hydrocarbon producer in the San Juan Basin (approximately 117 million barrels of oil and 79 billion cubic feet of gas). Because of reservoir heterogeneity, ultimate Tocito oil recovery factors are low, generally between 10 and 20 percent. To enhance understanding of permeability heterogeneity in the Tocito, we have undertaken a detailed surface and subsurface investigation. A total of 2,697 permeability measurements have been made using minipermeameters. Permeability variationmore » within the Tocito is controlled by two principal factors: lithofacies and burial/diagenetic history. Coarser grained and better sorted lithofacies have the highest permeability. The permeability values from outcrop and shallow subsurface cores are dramatically higher than those from deep subsurface cores. This is due to dissolution of grains and calcite cement, and decompaction that preferentially affected the outcrop and shallow subsurface. Correlation lengths for permeability values along horizontal transacts are typically less than 3 m, whereas those for vertical transacts are usually less than 0.6 m. These data suggest that small grid block sizes should be used during reservoir simulations if the investigator wishes to accurately capture the reservoir heterogeneity.« less

  8. Permeability structure of a highly heterogeneous transgressive-marine complex: Tocito Sandstone, New Mexico

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lambert, M.L.; Cole, R.D.

    1996-12-31

    The Tocito Sandstone Member of the Mancos Shale is an Upper Cretaceous shallow-marine sandstone and mudrock complex deposited along the western margin of the Western Interior seaway. The Tocito is a major hydrocarbon producer in the San Juan Basin (approximately 117 million barrels of oil and 79 billion cubic feet of gas). Because of reservoir heterogeneity, ultimate Tocito oil recovery factors are low, generally between 10 and 20 percent. To enhance understanding of permeability heterogeneity in the Tocito, we have undertaken a detailed surface and subsurface investigation. A total of 2,697 permeability measurements have been made using minipermeameters. Permeability variationmore » within the Tocito is controlled by two principal factors: lithofacies and burial/diagenetic history. Coarser grained and better sorted lithofacies have the highest permeability. The permeability values from outcrop and shallow subsurface cores are dramatically higher than those from deep subsurface cores. This is due to dissolution of grains and calcite cement, and decompaction that preferentially affected the outcrop and shallow subsurface. Correlation lengths for permeability values along horizontal transacts are typically less than 3 m, whereas those for vertical transacts are usually less than 0.6 m. These data suggest that small grid block sizes should be used during reservoir simulations if the investigator wishes to accurately capture the reservoir heterogeneity.« less

  9. Antenna cab interior showing waveguide from external parabolic antenna (later ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Antenna cab interior showing waveguide from external parabolic antenna (later addition), looking north. - Western Union Telegraph Company, Jennerstown Relay, Laurel Summit Road off U.S. 30, Laughlintown, Westmoreland County, PA

  10. Interior view, perspective view looking from the east southeast to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, perspective view looking from the east southeast to fireplace and mantel - National Park Seminary, Music Hall, Linden Lane at western edge of campus, Silver Spring, Montgomery County, MD

  11. Interior view, room 1103 northeast anteroom, general view to show ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, room 1103 northeast anteroom, general view to show fireplace and windows - National Park Seminary, Music Hall, Linden Lane at western edge of campus, Silver Spring, Montgomery County, MD

  12. Schematic of Mars Interior

    NASA Image and Video Library

    1997-10-14

    The interior of Mars is simply modeled as a core and mantle with a thin crust, similar to Earth. Mars' size and total mass have been determined by previous missions. Given four parameters, the core size and mass, and mantle size and mass can be determined. The combination of Pathfinder Doppler data with earlier data from the Viking landers has determined a third parameter, the moment of inertia, through measurement of Mars' precession rate. A fourth measurement is needed to complete the interior model. This may be achieved through future Doppler tracking of Pathfinder, since the presence of a fluid core may be detectable through its effect on Mars' nutation. The determination of the moment of inertia is a significant constraint on possible models for Mars' interior. If the core is as dense as possible (i.e. completely iron) and the mantle is similar to Earth's (or similar to the SNC meteorites thought to originate on Mars) then the minimum core radius is about 1300 km. If the core is made of less-dense material (i.e. a mixture of iron and sulfur) then the core radius is probably no more than 2000 km. Sojourner spent 83 days of a planned seven-day mission exploring the Martian terrain, acquiring images, and taking chemical, atmospheric and other measurements. The final data transmission received from Pathfinder was at 10:23 UTC on September 27, 1997. Although mission managers tried to restore full communications during the following five months, the successful mission was terminated on March 10, 1998. http://photojournal.jpl.nasa.gov/catalog/PIA00974

  13. Freezing tolerance of conifer seeds and germinants.

    PubMed

    Hawkins, B J; Guest, H J; Kolotelo, D

    2003-12-01

    Survival after freezing was measured for seeds and germinants of four seedlots each of interior spruce (Picea glauca x engelmannii complex), lodgepole pine (Pinus contorta Dougl. ex Loud.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western red cedar (Thuja plicata Donn ex D. Donn). Effects of eight seed treatments on post-freezing survival of seeds and germinants were tested: dry, imbibed and stratified seed, and seed placed in a growth chamber for 2, 5, 10, 15, 20 or 30 days in a 16-h photoperiod and a 22/17 degrees C thermoperiod. Survival was related to the water content of seeds and germinants, germination rate and seedlot origin. After freezing for 3 h at -196 degrees C, dry seed of most seedlots of interior spruce, Douglas-fir and western red cedar had 84-96% germination, whereas lodgepole pine seedlots had 53-82% germination. Freezing tolerance declined significantly after imbibition in lodgepole pine, Douglas-fir and interior spruce seed (western red cedar was not tested), and mean LT50 of imbibed seed of these species was -30, -24.5 and -20 degrees C, respectively. Freezing tolerance continued to decline to a minimum LT50 of -4 to -7 degrees C after 10 days in a growth chamber for interior spruce, Douglas-fir and lodgepole pine, or after 15 days for western red cedar. Minimum freezing tolerance was reached at the stage of rapid hypocotyl elongation. In all species, a slight increase in freezing tolerance of germinants was observed once cotyledons emerged from the seed coat. The decrease in freezing tolerance during the transition from dry to germinating seed correlated with increases in seed water content. Changes in freezing tolerance between 10 and 30 days in the growth chamber were not correlated with seedling water content. Within a species, seedlots differed significantly in freezing tolerance after 2 or 5 days in the growth chamber. Because all seedlots of interior spruce and lodgepole pine germinated quickly, there was no correlation between seedlot hardiness and rate of germination. Germination rate and freezing tolerance of Douglas-fir and western red cedar seedlots was negatively correlated. There was a significant correlation between LT50 after 10 days in the growth chamber and minimum spring temperature at the location of seedlot origin for interior spruce and three seedlots of western red cedar, but no relationship was apparent for lodgepole pine and Douglas-fir.

  14. Manipulating the optical properties of symmetrically branched Au/Pd nanocrystals through interior design.

    PubMed

    DeSantis, Christopher J; Skrabalak, Sara E

    2014-05-25

    Au/Pd octopods with hollow, cubic interiors and Oh symmetry were synthesized for the first time by etching core@shell Pd@Au/Pd octopods to selectively remove their Pd interiors. Integration of multiple architectural features - in this case branching symmetry, composition, and interior design - into one nanostructure provides design strategies to new plasmonic colloids.

  15. The late Cenomanian oyster Lopha staufferi (Bergquist, 1944) - the oldest ribbed oyster in the Upper Cretaceous of the Western Interior of the United States

    NASA Astrophysics Data System (ADS)

    Hook, Stephen C.; Cobban, William A.

    2016-12-01

    Lopha staufferi (Bergquist, 1944) is a medium-sized, ribbed, Late Cretaceous oyster with a slightly curved axis and a zigzag commissure; it appears suddenly and conspicuously in upper Cenomanian rocks in the Western Interior Basin of the United States. At maturity, the ribs on both valves thicken into steep flanks that allow the oyster to increase interior volume without increasing its exterior footprint on the seafloor. Lopha staufferi is the first (earliest) ribbed oyster in the Late Cretaceous of the Western Interior, but has no ancestor in the basin. It disappears from the rock record as suddenly as it appeared, leaving no direct descendent in the basin. In the southern part of the basin where it is well constrained, L. staufferi is restricted stratigraphically to the upper Cenomanian Metoicoceras mosbyense Zone (= Dunveganoceras conditum Zone in the north). Lopha staufferi has an unusual paleogeographic distribution, occurring in only two, widely scattered areas in the basin. It has been found at several localities near the western shoreline of the Late Cretaceous Seaway in west-central New Mexico and adjacent Arizona, and in localities 1,900 km (1,200 mi) to the northeast near the eastern shoreline in northeastern Minnesota, but nowhere in between. In west-central New Mexico and adjacent Arizona, L. staufferi is a guide fossil to the Twowells Tongue of the Dakota Sandstone.

  16. Contamination Control of Freeze Shoe Coring System for Collection of Aquifer Sands

    NASA Astrophysics Data System (ADS)

    Homola, K.; van Geen, A.; Spivack, A. J.; Grzybowski, B.; Schlottenmier, D.

    2017-12-01

    We have developed and tested an original device, the freeze-shoe coring system, designed to recover undisturbed samples of water contained in sand-dominated aquifers. Aquifer sands are notoriously difficult to collect together with porewater from coincident depths, as high hydraulic permeability leads to water drainage and mixing during retrieval. Two existing corer designs were reconfigured to incorporate the freeze-shoe system; a Hydraulic Piston (HPC) and a Rotary (RC) Corer. Once deployed, liquid CO­2 contained in an interior tank is channeled to coils at the core head where it changes phase, rapidly cooling the deepest portion of the core. The resulting frozen core material impedes water loss during recovery. We conducted contamination tests to examine the integrity of cores retrieved during a March 2017 yard test deployment. Perfluorocarbon tracer (PFC) was added to the drill fluid and recovered cores were subsampled to capture the distribution of PFC throughout the core length and interior. Samples were collected from two HPC and one RC core and analyzed for PFC concentrations. The lowest porewater contamination, around 0.01% invasive fluid, occurs in the center of both HPC cores. The greatest contamination (up to 10%) occurs at the disturbed edges where core material contacts drill fluid. There was lower contamination in the core interior than top, bottom, and edges, as well as significantly lower contamination in HPC cores that those recovered with the RC. These results confirm that the freeze-shoe system, proposed for field test deployments in West Bengal, India, can successfully collect intact porewater and sediment material with minimal if any contamination from drill fluid.

  17. 12. October 1972. INTERIOR VIEW OF ROOF TRUSS SYSTEM. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. October 1972. INTERIOR VIEW OF ROOF TRUSS SYSTEM. - Atlantic & Great Western Railroad, Meadville Repair Shops, Blacksmith Shop, East bank of French Creek, 800 feet South of Spring Street, Meadville, Crawford County, PA

  18. Interior view, room 1103, view of fireplace and mantel, and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, room 1103, view of fireplace and mantel, and inglenook, looking from the southeast - National Park Seminary, Music Hall, Linden Lane at western edge of campus, Silver Spring, Montgomery County, MD

  19. 76 FR 28078 - Notice of Inventory Completion: Western Michigan University, Anthropology Department, Kalamazoo, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-13

    ...: Western Michigan University, Anthropology Department, Kalamazoo, MI AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: Western Michigan University, Anthropology Department, has completed an... University, Anthropology Department. Disposition of the human remains and associated funerary objects to the...

  20. Interior of Tunnel No. 1356, Stick Pile Tunnel showing timber ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior of Tunnel No. 1356, Stick Pile Tunnel showing timber framing and missing posts, looking northeast. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

  1. 7. October 1972. INTERIOR VIEW, SHOWING THE ROOF TRUSS SYSTEM. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. October 1972. INTERIOR VIEW, SHOWING THE ROOF TRUSS SYSTEM. - Atlantic & Great Western Railroad, Meadville Repair Shops, Blacksmith Shop, East bank of French Creek, 800 feet South of Spring Street, Meadville, Crawford County, PA

  2. Interior view, room 1103, view looking from the southeast to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, room 1103, view looking from the southeast to fireplace and mantel and inglenook, with scale - National Park Seminary, Music Hall, Linden Lane at western edge of campus, Silver Spring, Montgomery County, MD

  3. 75 FR 36671 - Notice of Inventory Completion: Western Michigan University, Anthropology Department, Kalamazoo, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-28

    ... University, Anthropology Department, Kalamazoo, MI AGENCY: National Park Service, Interior. ACTION: Notice... objects in the possession of Western Michigan University, Anthropology Department, Kalamazoo, MI. The... funerary objects should contact LouAnn Wurst, Department of Anthropology, Western Michigan University, 1005...

  4. 75 FR 5105 - Notice of Inventory Completion: Western Michigan University, Anthropology Department, Kalamazoo, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-01

    ... University, Anthropology Department, Kalamazoo, MI AGENCY: National Park Service, Interior. ACTION: Notice... objects in the possession of Western Michigan University, Anthropology Department, Kalamazoo, MI. The... analysis. Dr. Robert Sundick, a physical anthropologist in the Anthropology Department at Western Michigan...

  5. 76 FR 36145 - Notice of Inventory Completion: Western Michigan University, Department of Anthropology...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-21

    ...: Western Michigan University, Department of Anthropology, Kalamazoo, MI AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: Western Michigan University, Department of Anthropology, has completed..., Department of Anthropology. Disposition of the human remains and associated funerary objects to the Indian...

  6. Interior view, general view in covered causeway (MD1109W) near ward ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, general view in covered causeway (MD-1109-W) near ward 114, looking from the northwest - National Park Seminary, Music Hall, Linden Lane at western edge of campus, Silver Spring, Montgomery County, MD

  7. Hiding the interior region of core-shell nanoparticles with quantum invisible cloaks

    NASA Astrophysics Data System (ADS)

    Lee, Jeng Yi; Lee, Ray-Kuang

    2014-04-01

    Based on the scattering cancellation, we provide a method not only making a nanoparticle nearly invisible, but also hiding its interior region from the outside probing matter wave. By applying the interplay among the nodal points of partial waves along with the concept of streamline in fluid dynamics for probability flux, a quantum invisible cloak to the electron transport in a host semiconductor is demonstrated by simultaneously guiding the probability flux outside a hidden region and keeping the total scattering cross section negligible. As the probability flux vanishes in the interior region, one can embed any materials inside a multiple core-shell nanoparticle without affecting physical observables from the outside. Our results reveal the possibility to design a protection shield layer for fragile interior parts from the impact of transport electrons.

  8. 43 CFR 3593.1 - Core or test hole cores, samples, cuttings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    .... (d) When drilling on lands with potential for encountering high pressure oil, gas or geothermal... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Core or test hole cores, samples, cuttings...) EXPLORATION AND MINING OPERATIONS Bore Holes and Samples § 3593.1 Core or test hole cores, samples, cuttings...

  9. 43 CFR 3593.1 - Core or test hole cores, samples, cuttings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... (d) When drilling on lands with potential for encountering high pressure oil, gas or geothermal... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Core or test hole cores, samples, cuttings...) EXPLORATION AND MINING OPERATIONS Bore Holes and Samples § 3593.1 Core or test hole cores, samples, cuttings...

  10. 43 CFR 3593.1 - Core or test hole cores, samples, cuttings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    .... (d) When drilling on lands with potential for encountering high pressure oil, gas or geothermal... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Core or test hole cores, samples, cuttings...) EXPLORATION AND MINING OPERATIONS Bore Holes and Samples § 3593.1 Core or test hole cores, samples, cuttings...

  11. 43 CFR 3593.1 - Core or test hole cores, samples, cuttings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... (d) When drilling on lands with potential for encountering high pressure oil, gas or geothermal... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Core or test hole cores, samples, cuttings...) EXPLORATION AND MINING OPERATIONS Bore Holes and Samples § 3593.1 Core or test hole cores, samples, cuttings...

  12. Albian to Santonian carbon isotope excursions and faunal extinctions in the Canadian Western Interior Sea: Recognition of eustatic sea-level controls on a forebulge setting

    NASA Astrophysics Data System (ADS)

    Schröder-Adams, Claudia J.; Herrle, Jens O.; Tu, Qiang

    2012-12-01

    The forebulge region of the Cretaceous Canadian Western Interior Sea (CWIS) was susceptible to subaerial exposure and marine erosion during sea level lowstands. The middle Albian to Santonian record as cored at Cold Lake, east-central Alberta, Canada documents numerous disconformities that are expressed in bioclastic concentration horizons and faunal extinctions and turnovers. Detailed comparison between a newly established δ13Corg. record measured on bulk sediment at Cold Lake and a combined δ13Ccarb. reference curve based on the Cretaceous English chalk and SE France hemipelagic marlstones highlights missing positive and negative δ13C excursions at the CWIS forebulge and thus missing sections that precisely corroborate with sequence boundaries. Disconformable boundaries correlate closely with global sea-level lowstands as established for the Cretaceous North Atlantic suggesting a pronounced eustatic influence on the CWIS forebulge setting. Sequence boundaries occur in the uppermost Middle Albian, lowermost Upper Albian, Albian/Cenomanian boundary, Cenomanian/Turonian boundary, middle Turonian to lower Coniacian and uppermost Middle Santonian, each followed by a positive δ13C excursion. Oceanic anoxic events 1d, 2 and 3 are recognized and linked to major faunal and floral assemblage changes. Of these the Albian/Cenomanian biotic turnover is the most severe in the CWIS marked by the total loss of Albian benthic foraminifera species. Causes of this benthic extinction might be linked to a period of anoxia (OAE 1d) during the latest Albian followed by sea-level controlled basin restriction.

  13. 76 FR 19067 - Agency Information Collection Extension

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-06

    ... under established marketing plans, Western needs to be able to collect information to evaluate who will... Federal reclamation program.\\2\\ The basic principle of the Reclamation Act of 1902 was that the United... marketing functions of the Department of the Interior to Western.\\8\\ Pursuant to this authority, Western...

  14. 76 FR 70748 - Outer Continental Shelf (OCS), Central and Western Gulf of Mexico, Oil and Gas Lease Sales for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-15

    ... DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management Outer Continental Shelf (OCS), Central and Western Gulf of Mexico, Oil and Gas Lease Sales for Years 2012-2017 AGENCY: Bureau of Ocean... 229, Western GOM 2012 Sale 227, Central GOM 2013 Sale 233, Western GOM 2013 Sale 231, Central GOM 2014...

  15. 8. INTERIOR, EMERGENCY ROOM, NORTHEAST OF MAIN CORRIDOR INTERSECTION (NEAR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. INTERIOR, EMERGENCY ROOM, NORTHEAST OF MAIN CORRIDOR INTERSECTION (NEAR WESTERN, MAIN ENTRY), FROM ENTRY IN NORTHWESTERN CORNER, LOOKING SOUTHEAST. - Oakland Naval Supply Center, Administration Building-Dental Annex-Dispensary, Between E & F Streets, East of Third Street, Oakland, Alameda County, CA

  16. Age of the Lava Creek supereruption and magma chamber assembly at Yellowstone based on 40Ar/39Ar and U-Pb dating of sanidine and zircon crystals

    NASA Astrophysics Data System (ADS)

    Vazquez, J. A.; Matthews, N. E.; Calvert, A. T.

    2015-12-01

    The last supereruption from the Yellowstone Plateau formed Yellowstone caldera and ejected the >1000 km3 of rhyolite that composes the Lava Creek Tuff (LCT). Tephra from the eruption blanketed much of the western United States, and is a key Quaternary chronostratigraphic marker, in particular for dating deposition of mid-Pleistocene glacial and pluvial deposits in western North America. We performed 40Ar/39Ar dating of single sanidines to delimit eruption age, and ion microprobe U-Pb and trace-element analyses of crystal faces on single zircons to characterize magmatic evolution and date near-eruption crystallization, as well as analyses of crystal interiors to date the interval of zircon crystallization. Sanidines from the two LCT members A and B yield an 40Ar/39Ar isochron date of 631 ± 4 ka (2σ). Crystal faces on zircons from both members yield a weighted mean 206Pb/238U date of 627 ± 6 ka (2σ) and have trace element concentrations that vary with eruptive stratigraphy. Zircon interiors yield a weighted mean 206Pb/238U date of 660 ± 6 ka, and reveal reverse and/or oscillatory zoning of trace element concentrations, with many crystals containing high-U concentrations and dark cathodoluminescence (CL) cores. These crystals with high-U cores are possibly sourced from 'defrosting' of melt-impregnated margins of the growing subvolcanic reservoir. LCT sanidines mirror the variation of zircon composition within the eruptive stratigraphy, with crystals from upper LCT-A and basal LCT-B having bright-CL rims with high Ba concentrations, suggesting late crystallization after addition of less evolved silicic magma. The occurrence of distal LCT in stratigraphic sequences marking the Marine Isotope Stage 16-15 transition supports the apparent eruption age of ca. 631 ka. These results reveal that Lava Creek zircons record episodic heating, renewed crystallization, and an overall up-temperature evolution for Yellowstone's subvolcanic reservoir in the 103-104 year interval before eruption.

  17. Thiolated DNA-based chemistry and control in the structure and optical properties of plasmonic nanoparticles with ultrasmall interior nanogap.

    PubMed

    Oh, Jeong-Wook; Lim, Dong-Kwon; Kim, Gyeong-Hwan; Suh, Yung Doug; Nam, Jwa-Min

    2014-10-08

    The design, synthesis and control of plasmonic nanostructures, especially with ultrasmall plasmonically coupled nanogap (∼1 nm or smaller), are of significant interest and importance in chemistry, nanoscience, materials science, optics and nanobiotechnology. Here, we studied and established the thiolated DNA-based synthetic principles and methods in forming and controlling Au core-nanogap-Au shell structures [Au-nanobridged nanogap particles (Au-NNPs)] with various interior nanogap and Au shell structures. We found that differences in the binding affinities and modes among four different bases to Au core, DNA sequence, DNA grafting density and chemical reagents alter Au shell growth mechanism and interior nanogap-forming process on thiolated DNA-modified Au core. Importantly, poly A or poly C sequence creates a wider interior nanogap with a smoother Au shell, while poly T sequence results in a narrower interstitial interior gap with rougher Au shell, and on the basis of the electromagnetic field calculation and experimental results, we unraveled the relationships between the width of the interior plasmonic nanogap, Au shell structure, electromagnetic field and surface-enhanced Raman scattering. These principles and findings shown in this paper offer the fundamental basis for the thiolated DNA-based chemistry in forming and controlling metal nanostructures with ∼1 nm plasmonic gap and insight in the optical properties of the plasmonic NNPs, and these plasmonic nanogap structures are useful as strong and controllable optical signal-generating nanoprobes.

  18. Silvics of western white pine

    Treesearch

    Charles A. Wellner

    1962-01-01

    Western white pine grows along west coast mountain ranges from Vancouver Island and the Homathko River on the adjacent mainland in British Columbia southward to the San Bernardino Mountains of southern California (13, 65, 75, 83). In the interior its range is from Quesnel Lake through the Selkirk Mountains of British Columbia southward into northern Idaho, western...

  19. 75 FR 1408 - Pick-Sloan Missouri Basin Program, Eastern and Western Division Proposed Project Use Power Rate

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-11

    ... of Proposed Pick-Sloan Missouri Basin Program, Eastern and Western Divisions, Project Use Power Rate...) for Project Use Power for the Pick-Sloan Missouri Basin Program (P-SMBP), Eastern and Western... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Pick-Sloan Missouri Basin Program, Eastern and...

  20. 75 FR 22423 - Pick-Sloan Missouri Basin Program, Eastern and Western Division Proposed Project Use Power Rate

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-28

    ...: Reopening of comment period for review of the Pick-Sloan Missouri Basin Program, Eastern and Western... reopening the comment period for the Pick-Sloan Missouri Basin Program, Eastern and Western Division... DEPARTMENT OF THE INTERIOR Bureau of Reclamation Pick-Sloan Missouri Basin Program, Eastern and...

  1. The Cretaceous Polar and Western Interior seas: paleoenvironmental history and paleoceanographic linkages

    NASA Astrophysics Data System (ADS)

    Schröder-Adams, Claudia

    2014-03-01

    This study reviews the Cretaceous histories of the Polar and Western Interior seas as recorded in the Canadian High Arctic Sverdrup Basin, Beaufort-Mackenzie Basin of northwest Canada and Western Canadian Foreland Basin. Newly emerging stratigraphic, paleoclimatic and paleoenvironmental interpretations from the polar realm allow for a fresh look at the response of this oceanic system to global climatic trends and sea-level histories over 35 Ma. Sverdrup basin localities on Axel Heiberg and Ellef Ringnes islands represent shelf to slope environments that contrasted with the shallow water and low gradient settings of the Canadian Western Interior Sea. Both marine systems, connected throughout Aptian to Maastrichtian time, responded to global transgressive-regressive cycles resulting in dynamic paleogeographic changes. The upper Aptian to Campanian succession of the Polar Sea shows at least two unconformable boundaries; one at the Albian/Cenomanian transition and another within the upper Cenomanian. The shallow basin setting and in particular the forebulge and backbulge settings of the Western Canadian Foreland Basin are characterized by multiple erosional surfaces throughout the Cretaceous succession. The Upper Albian disconformity is widely discernible close to the entrance of the Western Interior Sea to the Polar Sea. This suggests a short-lived closure of the latest Albian Mowry Sea that might have been responsible for the large loss of benthic foraminiferal species at this time. Several oceanic anoxic events are documented in these basins representing their response to global climate dynamics. During the Late Cretaceous temperature maximum benthic foraminiferal communities were severely restricted by bottom water hypoxia in both basins. A stratified water column might have been the result of increased freshwater runoff under warm, humid conditions. These conditions supported vegetation up into the polar latitudes that added abundant organic matter to marine shelf systems. Conversely, the Canadian Western Interior Sea biotic communities were controlled by watermasses of two or maybe three different sources and physical properties including the Polar, Tethyan and a possibly third source from the emerging Labrador Sea through the Hudson Seaway. Where the southern and northern watermasses mixed, plankton might have been influenced by oceanic fronts, forming mass kills through sinking of dense waters. Migration of calcareous phyto- and zooplankton was controlled by a temperature and salinity gradient and did not invade northern regions. Siliceous plankton occurred and is more commonly found in the Sverdrup Basin, but taphonomic loss through deep burial needs to be taken into account.

  2. Interior of Mars from spacecraft and complementary data.

    NASA Astrophysics Data System (ADS)

    Dehant, Veronique

    2015-04-01

    Mars, as Earth, Venus and Mercury is a terrestrial planet having, in addition to the mantle and lithosphere, a core composed of an iron alloy. This core might be completely liquid, completely solid or may contain a solid part (the inner core) and a liquid part. The existence of a magnetic field around a planet is mainly explained by the presence of motions in the liquid part in the core. The absence of a magnetic field does not help in constraining the state of the core as it might be completely solid or completely liquid but the motion (convection) might not be sufficient to maintain it, or even contain a growing inner core inside a liquid core composed of iron or Nickel and a percentage of light element corresponding to the eutectic composition (no precipitation). The planet Mars is smaller than Earth. It has evolved differently. We know for the Earth that the core is liquid and that the inner core is forming by precipitation of iron. For Mars spacecraft observation of the gravity field and its time variation allow us to obtain the effect of mass repartition, and in particular those induced by the solid tides. These tidal deformation of the planet are larger for a planet with a liquid core than for a completely solid planet. Recent spacecraft orbiting around Mars (MGS, Mars Odyssey, MRO, Mars Express) have allowed to obtain the k2 tidal Love numbers. This measurement is rather at the limit of what the observation can tell us but seems to indicate that Mars has a liquid core. The absence of a present-day global magnetic field places Mars in the situation where the inner core is not yet forming or has reached the eutectic. Physical observation of the planet other than tides also allow us to obtain information about the interior of Mars: its rotation and orientation changes. Planetary rotation can be separated into the rotation speed around an axis and the orientation of this axis (or another axis of the planet) in space. Most of us know that the rotation of a boiled egg noticeably differs from that of a raw egg. This simple observation shows that information on the inside of an object can be obtained from its rotation. The same idea applies to the rotation of celestial bodies. Their rotation changes and orientation changes provide information on the interior. For Mars, as for the Earth, it is mainly the changes in the orientation that are important to characterize their interiors, the length-of-day variations being mostly related to atmospheric angular moment transfer to the solid planet. The orientation changes are called precession, the long-term change, and nutation, the periodic wiggly short-term changes that are the most interesting to obtain information about the core. Nutations have up to now only been unambiguously observed for the Earth, but the InSIGHT (Interior exploration using Seismic Investigations, Geodesy, and Heat Transport) NASA mission to be launched in 2016, will carry out an X-band transponder enabling us to do Doppler measurements on the motion of Mars with respect to Earth, and therewith to determine the nutations and the interior structure of Mars.

  3. Impacts of an Extreme Early-Season Freeze Event in the Interior Pacific Northwest (30 October-3 November 2002) on Western Juniper Woodlands.

    NASA Astrophysics Data System (ADS)

    Knapp, Paul A.; Soulé, Peter T.

    2005-07-01

    In mid-autumn 2002, an exceptional 5-day cold spell affected much of the interior Pacific Northwest, with minimum temperatures averaging 13°C below long-term means (1953-2002). On 31 October, minimum temperature records occurred at 98 of the 106 recording stations, with records lowered in some locations by 9°C. Calculation of recurrence intervals of minimum temperatures shows that 50% of the stations experienced a >500-yr event. The synoptic conditions responsible were the development of a pronounced high pressure ridge over western Canada and an intense low pressure area centered in the Intermountain West that promoted strong northeasterly winds. The cold spell occurred near the end of the growing season for an ecologically critical and dominant tree species of the interior Pacific Northwest—western juniper—and followed an extended period of severe drought. In spring 2003, it became apparent that the cold had caused high rates of tree mortality and canopy dieback in a species that is remarkable for its longevity and resistance to climatic stress. The cold event altered western juniper dominance in some areas, and this alteration may have long-term impacts on water budgets, fire intensities and frequencies, animal species interrelationships, and interspecific competition among plant species.

  4. 4. FIRST FLOOR INTERIOR, AMMONIA COMPRESSION DYNAMOS IN MACHINERY ROOM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. FIRST FLOOR INTERIOR, AMMONIA COMPRESSION DYNAMOS IN MACHINERY ROOM ALONG SOUTH SIDE OF WESTERN PORTION OF BUILDING, FROM EASTERN ENTRANCE TO MACHINERY ROOM, LOOKING WEST. - Oakland Naval Supply Center, Cold Storage Warehouse, South of C Street between First & Second Street, Oakland, Alameda County, CA

  5. Upper Miocene reef complex of Mallorca, Balearic Islands, Spain

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pomar, L.

    1988-02-01

    The late Tortonian-Messinian coral reef platform of south Mallorca onlaps a folded middle late Miocene carbonate platform on which progradation of up to 20 km occurs. Vertical sea cliffs (up to 100 m high) superbly show the last 5 km of this progradation and complement the numerous water-well cores from the island interior. The Mallorca reef presents the most complete facies zonation of the Miocene reefs of the western Mediterranean. The reef wall framework is up to 20 m thick and shows (1) erosional reef flat with reef breccia and small corals; (2) spur-and-grove zone with large, massive corals; (3)more » deep buttresses and pinnacles with terraces of branching corals; and (4) deep reef wall with flat, laminar coral colonies, branching red algae, and Halimeda sands.« less

  6. Earth Core and Inner Core: What Can We Learn From a Bayesian Inversion of Combined Nutation and Surface Gravimetry Data?

    NASA Astrophysics Data System (ADS)

    Lambert, S. B.; Ziegler, Y.; Rosat, S.; Bizouard, C.

    2017-12-01

    Nutation time series derived from very long baseline interferometry (VLBI) and time varying surface gravity data recorded by superconducting gravimeters (SG) have long been used separately to assess the Earth's interior via the estimation of the free core and inner core resonance effects on nutation or tidal gravity. The results obtained from these two techniques have shown recently to be consistent, making relevant the combination of VLBI and SG observables and the estimation of Earth's interior parameters in a single inversion. We present here the results of combining nutation and surface gravity time series to improve estimates of the Earth's core and inner core resonant frequencies. We use VLBI nutation time series spanning 1984-2016 derived by several analysis centers affiliated to the International VLBI Service for Geodesy and Astrometry, together with surface gravity data from about 15 SG stations. We address the resonance model used for describing the Earth's interior response to tidal excitation, the data preparation consisting of the error recalibration and amplitude fitting to nutation data, and processing of SG time-varying gravity to remove any gaps, spikes, steps and other disturbances, followed by the tidal analysis with the ETERNA 3.4 software package. New estimates of the resonant periods are proposed and correlations between the parameters are investigated.

  7. Combining nutation and surface gravity observations to estimate the Earth's core and inner core resonant frequencies

    NASA Astrophysics Data System (ADS)

    Ziegler, Yann; Lambert, Sébastien; Rosat, Séverine; Nurul Huda, Ibnu; Bizouard, Christian

    2017-04-01

    Nutation time series derived from very long baseline interferometry (VLBI) and time varying surface gravity data recorded by superconducting gravimeters (SG) have long been used separately to assess the Earth's interior via the estimation of the free core and inner core resonance effects on nutation or tidal gravity. The results obtained from these two techniques have been shown recently to be consistent, making relevant the combination of VLBI and SG observables and the estimation of Earth's interior parameters in a single inversion. We present here the intermediate results of the ongoing project of combining nutation and surface gravity time series to improve estimates of the Earth's core and inner core resonant frequencies. We use VLBI nutation time series spanning 1984-2016 derived by the International VLBI Service for geodesy and astrometry (IVS) as the result of a combination of inputs from various IVS analysis centers, and surface gravity data from about 15 SG stations. We address here the resonance model used for describing the Earth's interior response to tidal excitation, the data preparation consisting of the error recalibration and amplitude fitting for nutation data, and processing of SG time-varying gravity to remove any gaps, spikes, steps and other disturbances, followed by the tidal analysis with the ETERNA 3.4 software package, the preliminary estimates of the resonant periods, and the correlations between parameters.

  8. Paleogeography and the Late Cretaceous of the Western Interior of middle North America; coal distribution and sediment accumulation

    USGS Publications Warehouse

    Roberts, Laura N. Robinson; Kirschbaum, Mark A.

    1995-01-01

    A synthesis of Late Cretaceous paleogeography of the Western Interior from Mexico to southwestern Canada emphasizes the areal distribution of peat-forming environments during six biostratigraphically constrained time intervals. Isopach maps of strata for each interval reveal the locations and magnitude of major depocenters. The paleogeographic framework provides insight into the relative importance of tectonism, eustasy, and climate on the accumulation of thick peats and their preservation as coals. A total of 123 basin summaries and their data provide the ground truth for construction of the isopach and paleogeographic maps.

  9. Hexavalent chromium monitor

    DOEpatents

    Tao, Shiquan; Winstead, Christopher B.

    2005-04-12

    A monitor is provided for use in measuring the concentration of hexavalent chromium in a liquid, such as water. The monitor includes a sample cell, a light source, and a photodetector. The sample cell is in the form of a liquid-core waveguide, the sample cell defining an interior core and acting as a receiver for the liquid to be analyzed, the interior surface of the sample cell having a refractive index of less than 1.33. The light source is in communication with a first end of the sample cell for emitting radiation having a wavelength of about and between 350 to 390 nm into the interior core of the waveguide. The photodetector is in communication with a second end of the waveguide for measuring the absorption of the radiation emitted by the light source by the liquid in the sample cell. The monitor may also include a processor electronically coupled to the photodetector for receipt of an absorption signal to determine the concentration of hexavalent chromium in the liquid.

  10. Integrated-magnetic apparatus

    NASA Technical Reports Server (NTRS)

    Bloom, Gordon E. (Inventor)

    1998-01-01

    Disclosure is made of an integrated-magnetic apparatus, comprising: winding structure for insulatingly carrying at least two generally flat, laterally offset and spaced apart electrical windings of a power converter around an aperture; a core having a flat exterior face, an interior cavity and an un-gapped core-column that is located within the cavity and that passes through the aperture of the winding structure; flat-sided surface carried by the core and forming an interior chamber that is located adjacent to the flat face of the core and forming a core-column that has a gap and that is located within the chamber; and structure, located around the gapped core-column, for carrying a third electrical winding of the power converter. The first two electrical windings are substantially located within the cavity and are adapted to be transformingly coupled together through the core. The third electrical winding is adapted to be inductively coupled through the gapped core-column to the other electrical windings, and is phased to have the magnetic flux passing through the gapped core-column substantially in the same direction as the magnetic flux passing through the un-gapped core-column and to have substantially the same AC components of flux in the gapped core-column and in the un-gapped core-column.

  11. Ganymede G1 & G2 Encounters - Interior of Ganymede

    NASA Image and Video Library

    1997-12-16

    NASA's Voyager images are used to create a global view of Ganymede. The cut-out reveals the interior structure of this icy moon. This structure consists of four layers based on measurements of Ganymede's gravity field and theoretical analyses using Ganymede's known mass, size and density. Ganymede's surface is rich in water ice and Voyager and Galileo images show features which are evidence of geological and tectonic disruption of the surface in the past. As with the Earth, these geological features reflect forces and processes deep within Ganymede's interior. Based on geochemical and geophysical models, scientists expected Ganymede's interior to either consist of: a) an undifferentiated mixture of rock and ice or b) a differentiated structure with a large lunar sized "core" of rock and possibly iron overlain by a deep layer of warm soft ice capped by a thin cold rigid ice crust. Galileo's measurement of Ganymede's gravity field during its first and second encounters with the huge moon have basically confirmed the differentiated model and allowed scientists to estimate the size of these layers more accurately. In addition the data strongly suggest that a dense metallic core exists at the center of the rock core. This metallic core suggests a greater degree of heating at sometime in Ganymede's past than had been proposed before and may be the source of Ganymede's magnetic field discovered by Galileo's space physics experiments. http://photojournal.jpl.nasa.gov/catalog/PIA00519

  12. 18. INTERIOR SURFACE OF THE SHORT SOUTH WALL OF AR9, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. INTERIOR SURFACE OF THE SHORT SOUTH WALL OF AR-9, WITH THE MORE RECENT CONCRETE BLOCK CONTROL ROOM AT THE LEFT AND ASSOCIATED CONCRETE PAVING IN THE FOREGROUND. - Edwards Air Force Base, South Base, Rammed Earth Aircraft Dispersal Revetments, Western Shore of Rogers Dry Lake, Boron, Kern County, CA

  13. Mercury sedimentation in lakes in western Whatcom County, Washington, USA and its relation to local industrial and municipal atmospheric sources

    USGS Publications Warehouse

    Paulson, A.J.; Norton, D.

    2008-01-01

    Concentrations of mercury (Hg) were measured in six dated cores from four lakes in western Whatcom County, Washington, USA, that were at various bearings from a chlor-alkali plant, two municipal waste incinerators and a municipal sewage sludge incinerator. The importance of atmospheric emissions of Hg from these local municipal and industrial sources was evaluating by comparing the temporal trends in sedimentation of the lake cores with the emission history of each Hg species and by examining the geographical distribution of Hg sedimentation in relation to the region's primary wind pattern. Local municipal and industrial sources of atmospheric Hg were not responsible for the majority of the Hg in the upper layer of sediments of Whatcom County lakes because of (1) the significant enrichment of Hg in lake sediments prior to emissions of local industrial and municipal sources in 1964, (2) smaller increases in Hg concentrations occurred after 1964, (3) the similarity of maximum enrichments found in Whatcom County lakes to those in rural lakes around the world, (4) the inconsistency of the temporal trends in Hg sedimentation with the local emission history, and (5) the inconsistency of the geographic trends in Hg sedimentation with estimated deposition. Maximum enrichment ratios of Hg in lake sediments between 2 and 3 that are similar to rural areas in Alaska, Minnesota, and New England suggest that global sources of Hg were primarily responsible for increases of Hg in Whatcom County lakes beginning about 1900. ?? 2007 GovernmentEmployee: U.S. Government, Department of Interior, U.S. Geological Survey.

  14. The first reported ceratopsid dinosaur from eastern North America (Owl Creek Formation, Upper Cretaceous, Mississippi, USA)

    PubMed Central

    2017-01-01

    Ceratopsids (“horned dinosaurs”) are known from western North America and Asia, a distribution reflecting an inferred subaerial link between the two landmasses during the Late Cretaceous. However, this clade was previously unknown from eastern North America, presumably due to limited outcrop of the appropriate age and depositional environment as well as the separation of eastern and western North America by the Western Interior Seaway during much of the Late Cretaceous. A dentary tooth from the Owl Creek Formation (late Maastrichtian) of Union County, Mississippi, represents the first reported occurrence of Ceratopsidae from eastern North America. This tooth shows a combination of features typical of Ceratopsidae, including a double root and a prominent, blade-like carina. Based on the age of the fossil, we hypothesize that it is consistent with a dispersal of ceratopsids into eastern North America during the very latest Cretaceous, presumably after the two halves of North America were reunited following the retreat of the Western Interior Seaway. PMID:28560100

  15. The first reported ceratopsid dinosaur from eastern North America (Owl Creek Formation, Upper Cretaceous, Mississippi, USA).

    PubMed

    Farke, Andrew A; Phillips, George E

    2017-01-01

    Ceratopsids ("horned dinosaurs") are known from western North America and Asia, a distribution reflecting an inferred subaerial link between the two landmasses during the Late Cretaceous. However, this clade was previously unknown from eastern North America, presumably due to limited outcrop of the appropriate age and depositional environment as well as the separation of eastern and western North America by the Western Interior Seaway during much of the Late Cretaceous. A dentary tooth from the Owl Creek Formation (late Maastrichtian) of Union County, Mississippi, represents the first reported occurrence of Ceratopsidae from eastern North America. This tooth shows a combination of features typical of Ceratopsidae, including a double root and a prominent, blade-like carina. Based on the age of the fossil, we hypothesize that it is consistent with a dispersal of ceratopsids into eastern North America during the very latest Cretaceous, presumably after the two halves of North America were reunited following the retreat of the Western Interior Seaway.

  16. To Great and Useful Purpose: A History of the Wilmington District U.S. Army Corps of Engineers

    DTIC Science & Technology

    1984-05-01

    Carolina, lacking good natural harbors like those in South Carolina, was further barred from the ocean by a forbidding coastline . .. The western boundary...into the interior. The Coastal Plain is divided into the Western Coastal Plain subregion and the Tidewater subregion. The Western Coastal Plain is...except for cities such as Wilmington and Beaufort, generally opposed state-sponsored internal im- provements that would benefit the western half of

  17. Mapping traditional place names along the Koyukuk River: Koyukuk, Huslia, and Hughes, Western Interior Alaska

    USGS Publications Warehouse

    McCloskey, Sarah E.; Jones, Benjamin M.

    2014-01-01

    Koyukon Athabascan peoples have settled along the Koyukuk River in Western Interior Alaska for thousands of years using the surrounding landscape for subsistence and cultural resources. However, recent changes in climate, technology, resource availability, and way of life have affected land-use patterns in the region, as well as use of the Denaakk'e (Koyukon) language. The current Koyukon population is about 2,300, and about 150 still speak the language (the youngest of whom are in their fifties). In addition, Elders, important keepers of both language and traditional subsistence-use areas, are aging, and opportunities to record their knowledge are diminishing.

  18. Precise age of C33N-C32R magnetic-polarity reversal, San Juan Basin, New Mexico and Colorado

    USGS Publications Warehouse

    Fassett, James E.; Steiner, Maureen B.

    1997-01-01

    Polarity-chron boundary C33n-C32r has been identified in the Upper Cretaceous continental Farmington Sandstone Member of the Kirtland Shale in Hunter Wash in the southwest part of the San Juan Basin of New Mexico, and in the marine Lewis Shale at Chimney Rock, Colorado, in the northeast part of the basin. Single- and multiple-crystal laser fusion 40Ar/39Ar ages of sanidine crystals from volcanic ash beds bracketing the C33n-C32r polarity reversal at Hunter Wash establish its age as 73.50 ± 0.18 Ma. The reversal apparently occurs within the Baculites compressus Western Interior ammonite zone and within the Edmontonian land-vertebrate faunal zone. An 8 Ma hiatus separates Cretaceous and Tertiary rocks in the southern San Juan Basin. These findings provide a precise new interpolated Late Cretaceous tie point for geologic time scales, provide the basis for the direct correlation of Western Interior ammonite zones to European open-ocean faunal zones, and establish the first direct tie between continental and marine fossil zones within the Western Interior of North America.

  19. Long-period seismology on Europa: 1. Physically consistent interior models

    NASA Astrophysics Data System (ADS)

    Cammarano, F.; Lekic, V.; Manga, M.; Panning, M.; Romanowicz, B.

    2006-12-01

    In order to examine the potential of seismology to determine the interior structure and properties of Europa, it is essential to calculate seismic velocities and attenuation for the range of plausible interiors. We calculate a range of models for the physical structure of Europa, as constrained by the satellite's composition, mass, and moment of inertia. We assume a water-ice shell, a pyrolitic or a chondritic mantle, and a core composed of pure iron or iron plus 20 weight percent of sulfur. We consider two extreme mantle thermal states: hot and cold. Given a temperature and composition, we determine density, seismic velocities, and attenuation using thermodynamical models. While anelastic effects will be negligible in a cold mantle and the brittle part of the ice shell, strong dispersion and dissipation are expected in a hot convective mantle and the bulk of the ice shell. There is a strong relationship between different thermal structures and compositions. The ``hot'' mantle may maintain temperatures consistent with a liquid core made of iron plus light elements. For the ``cold scenarios,'' the possibility of a solid iron core cannot be excluded, and it may even be favored. The depths of the ocean and core-mantle boundary are determined with high precision, 10 km and 40 km, respectively, once we assume a composition and thermal structure. Furthermore, the depth of the ocean is relatively insensitive (4 km) to the core composition used.

  20. Unravelling the structural control of mississippi valley-type deposits and prospects in carbonate sequences of the Western Canada Sedimentary Basin

    USGS Publications Warehouse

    Pana, D.

    2006-01-01

    Re-examination of selected MVT outcrops and cores in the Interior Plains and Rocky Moun-tains of Alberta, corroborated with previous paragenetic, isotopic and structural data, suggests Laramide structural channelling of dolomitizing and mineralizing fluids into strained carbonate rocks. At Pine Point, extensional faults underlying the trends of MVT ore bodies and brittle faults overprinting the Great Slave Lake Shear Zone define apinnate fault geometry and appear to be kinematically linked. Chemical and isotopic characteristics of MVT parental fluids are consistent with seawater and brine convection within fault-confined verticalaquifers, strong water-basement rock interaction, metalleaching from the basement, and focused release of hydrothermal fluids within linear zones of strained carbonate caprocks. Zones of recurrent strain in the basement and a cap of carbonate strata constitute the critical criteria for MVTexploration target selection in the WCSB.

  1. An isotopic study of biogeochemical relationships between carbonates and organic carbon in the Greenhorn Formation

    NASA Technical Reports Server (NTRS)

    Hayes, J. M.; Popp, Brian N.; Takigiku, Ray; Johnson, Marcus W.

    1989-01-01

    Carbon-isotopic compositions of total carbonate, inoceramid carbonate, micritic carbonate, secondary cements, total organic carbon, and geoporphyrins have been measured in 76 different beds within a 17-m interval of a core through the Greenhorn Formation, an interbedded limestone and calcareous shale unit of Cretaceous age from the Western Interior Seaway of North America. Results are considered in terms of variations in the processes of primary production and in secondary processes. It is shown that the porphyrin isotopic record reflects primary isotopic variations more closely than the TOC isotopic record and that, in these sediments, TOC is enriched in C-13 relative to its primary precursor by 0.6 to 2.8 percent. This enrichment is attributed to isotope effects within the consumer foodweb and is associated with respiratory heterotrophy. Variation in this secondary enrichment are correlated with variations in the isotopic composition of marine carbonate.

  2. ACHP | News

    Science.gov Websites

    Search skip specific nav links Home arrow News arrow June 10, 2014 ACHP Joins Western States Tourism Western States Tourism Policy Council MOU June 9 in Colorado Springs, Colorado. Interior Secretary Sally promotion and tourism development. WGA Annual Meeting Day 1: President Obama, drought readiness, Secretary

  3. The Fuzziness of Giant Planets’ Cores

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Helled, Ravit; Stevenson, David

    2017-05-01

    Giant planets are thought to have cores in their deep interiors, and the division into a heavy-element core and hydrogen–helium envelope is applied in both formation and structure models. We show that the primordial internal structure depends on the planetary growth rate, in particular, the ratio of heavy elements accretion to gas accretion. For a wide range of likely conditions, this ratio is in one-to-one correspondence with the resulting post-accretion profile of heavy elements within the planet. This flux ratio depends sensitively on the assumed solid-surface density in the surrounding nebula. We suggest that giant planets’ cores might not bemore » distinct from the envelope and includes some hydrogen and helium, and the deep interior can have a gradual heavy-element structure. Accordingly, Jupiter’s core may not be well defined. Accurate measurements of Jupiter’s gravitational field by Juno could put constraints on Jupiter’s core mass. However, as we suggest here, the definition of Jupiter’s core is complex, and the core’s physical properties (mass, density) depend on the actual definition of the core and on the planet’s growth history.« less

  4. Expansion and contraction tension zones in western pinon-juniper woodlands under projected climate change

    Treesearch

    Jacob Gibson; Gretchen G. Moisen; Tracey S. Frescino; Thomas C. Jr. Edwards

    2012-01-01

    Populations of pinons and junipers across the interior west have been highly dynamic over the last two centuries, undergoing an overall expansion but punctuated with regional mortality. Accumulating demographic studies across the interior west indicate the drivers of expansion and contraction of populations are compounded by regional land use legacies, but have an...

  5. Birds and burns of the interior West: descriptions, habitats, and management in western forests.

    Treesearch

    Victoria Saab; William Block; Robin Russell; John Lehmkuhl; Lisa Bate; Rachel White

    2007-01-01

    This publication provides information about prescribed fire effects on habitats and populations of birds of the interior West and a synthesis of existing information on bird responses to fire across North America. Our literature synthesis indicated that aerial, ground, and bark insectivores favored recently burned habitats, whereas foliage gleaners preferred unburned...

  6. The evolution of the moon and the terrestrial planets

    NASA Technical Reports Server (NTRS)

    Toksoez, M. N.; Johnston, D. H.

    1974-01-01

    The thermal evolutions of the Moon, Mars, Venus and Mercury are calculated theoretically starting from cosmochemical condensation models. An assortment of geological, geochemical and geophysical data are used to constrain both the present day temperatures and the thermal histories of the planets' interiors. Such data imply that the planets were heated during or shortly after formation and that all the terrestrial planets started their differentiations early in their history. The moon, smallest in size, is characterized as a differentiated body with a crust, a thick solid mantle and an interior region which may be partially molten. Mars, intermediate in size, is assumed to have differentiated an Fe-FeS core. Venus is characterized as a planet not unlike the earth in many respects. Core formation has occurred probably during the first billion years after the formation. Mercury, which probably has a large core, may have a 500 km thick solid lithosphere and a partially molten core if it is assumed that some heat sources exist in the core.

  7. Lunar Love Numbers and the Deep Lunar Interior

    NASA Technical Reports Server (NTRS)

    Williams, J. G.; Boggs, D. H.; Ratcliff, J. T.; Dickey, J. O.

    2002-01-01

    Observationally determined values of the Love number k2 are larger than existing models of the lunar interior predict. The region between the deep moonquakes and core may be a low velocity zone from a partial melt. Additional information is contained in the original extended abstract.

  8. 76 FR 53940 - Notice of Public Meeting; Western Montana Resource Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-30

    ... management in Montana. During these meetings the council will participate in/discuss/act upon several topics... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLMTB07900 09 L10100000.PH0000 LXAMANMS0000] Notice of Public Meeting; Western Montana Resource Advisory Council AGENCY: Bureau of Land Management...

  9. 76 FR 27661 - Notice of Public Meeting; Western Montana Resource Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-12

    ... several topics, including reports from the Bureau of Land Management's Butte, Missoula and Dillon field... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLMTB07900 09 L10100000.PH0000 LXAMANMS0000] Notice of Public Meeting; Western Montana Resource Advisory Council AGENCY: Bureau of Land Management...

  10. NEUTRONIC REACTOR FUEL ELEMENT AND CORE SYSTEM

    DOEpatents

    Moore, W.T.

    1958-09-01

    This patent relates to neutronic reactors and in particular to an improved fuel element and a novel reactor core system for facilitating removal of contaminating fission products, as they are fermed, from association with the flssionable fuel, so as to mitigate the interferent effects of such fission products during reactor operation. The fuel elements are comprised of tubular members impervious to fluid and contatning on their interior surfaces a thin layer of fissionable material providing a central void. The core structure is comprised of a plurality of the tubular fuel elements arranged in parallel and a closed manifold connected to their ends. In the reactor the core structure is dispersed in a water moderator and coolant within a pressure vessel, and a means connected to said manifuld is provided for withdrawing and disposing of mobile fission product contamination from the interior of the feel tubes and manifold.

  11. Method for the production of fabricated hollow microspheroids

    DOEpatents

    Wickramanayake, Shan; Luebke, David R.

    2015-06-09

    The method relates to the fabrication of a polymer microspheres comprised of an asymmetric layer surrounding a hollow interior. The fabricated hollow microsphere is generated from a nascent hollow microsphere comprised of an inner core of core fluid surrounded by a dope layer of polymer dope, where the thickness of the dope layer is at least 10% and less than 50% of the diameter of the inner core. The nascent hollow microsphere is exposed to a gaseous environment, generating a vitrified hollow microsphere, which is subsequently immersed in a coagulation bath. Solvent exchange produces a fabricated hollow microsphere comprised of a densified outer skin surrounding a macroporous inner layer, which surrounds a hollow interior. In an embodiment, the polymer is a polyimide or a polyamide-imide, and the non-solvent in the core fluid and the coagulation bath is water. The fabricated hollow microspheres are particularly suited as solvent supports for gas separation processes.

  12. A coarse grained molecular dynamics simulation study on the structural properties of carbon nanotube-dendrimer composites.

    PubMed

    Kavyani, Sajjad; Dadvar, Mitra; Modarress, Hamid; Amjad-Iranagh, Sepideh

    2018-04-25

    By employing coarse grained (CG) molecular dynamics (MD) simulation, the effect of the size and hydrophilic/hydrophobic properties of the interior/exterior structures of the dendrimers in carbon nanotube (CNT)-dendrimer composites has been studied, to find a stable composite with high solubility in water and the capability to be used in drug delivery applications. For this purpose, composites consisting of core-shell dendrimer complexes including: [PPI{core}-PAMAM{shell}], [PAMAM{core}-polyethyleneglycol (PEG){shell}] and [PAMAM{core}-fattyacid (FTA){shell}] were constructed. A new CG model for the fatty acid (FTA) molecules as functionalized to the dendrimer was developed, which, unlike the previous models, could generate the structural conformations of the FTA properly. The obtained results indicated that the dendrimer complexes with short FTA chains can form stable composites with the CNT. Also, it was found that the pristine PAMAM and PPI-PAMAM with small PPI, and PAMAM-PEG dendrimers with short PEG chains, can distribute their chains into the water medium and interact with the CNT efficiently, to form a stable water-soluble CNT-dendrimer composite. The results demonstrated that the structural difference between the interior and exterior of a core-shell dendrimer complex can prevent the core and the interior layers of the dendrimer complex from interacting with the CNT. An overall analysis of the results manifested that the CNT-PAMAM:4-PEG:4 is the most stable composite, due to strong binding of the dendrimer with the CNT while also having high solubility in water, and its core retains its structure properly and unchanged, suitable for encapsulating drugs in the targeted delivery applications.

  13. Utilization of fluorescent microspheres and a green fluorescent protein-marked strain for assessment of microbiological contamination of permafrost and ground ice core samples from the Canadian High Arctic.

    PubMed

    Juck, D F; Whissell, G; Steven, B; Pollard, W; McKay, C P; Greer, C W; Whyte, L G

    2005-02-01

    Fluorescent microspheres were applied in a novel fashion during subsurface drilling of permafrost and ground ice in the Canadian High Arctic to monitor the exogenous microbiological contamination of core samples obtained during the drilling process. Prior to each drill run, a concentrated fluorescent microsphere (0.5-microm diameter) solution was applied to the interior surfaces of the drill bit, core catcher, and core tube and allowed to dry. Macroscopic examination in the field demonstrated reliable transfer of the microspheres to core samples, while detailed microscopic examination revealed penetration levels of less than 1 cm from the core exterior. To monitor for microbial contamination during downstream processing of the permafrost and ground ice cores, a Pseudomonas strain expressing the green fluorescent protein (GFP) was painted on the core exterior prior to processing. Contamination of the processed core interiors with the GFP-expressing strain was not detected by culturing the samples or by PCR to detect the gfp marker gene. These methodologies were quick, were easy to apply, and should help to monitor the exogenous microbiological contamination of pristine permafrost and ground ice samples for downstream culture-dependent and culture-independent microbial analyses.

  14. Utilization of Fluorescent Microspheres and a Green Fluorescent Protein-Marked Strain for Assessment of Microbiological Contamination of Permafrost and Ground Ice Core Samples from the Canadian High Arctic

    PubMed Central

    Juck, D. F.; Whissell, G.; Steven, B.; Pollard, W.; McKay, C. P.; Greer, C. W.; Whyte, L. G.

    2005-01-01

    Fluorescent microspheres were applied in a novel fashion during subsurface drilling of permafrost and ground ice in the Canadian High Arctic to monitor the exogenous microbiological contamination of core samples obtained during the drilling process. Prior to each drill run, a concentrated fluorescent microsphere (0.5-μm diameter) solution was applied to the interior surfaces of the drill bit, core catcher, and core tube and allowed to dry. Macroscopic examination in the field demonstrated reliable transfer of the microspheres to core samples, while detailed microscopic examination revealed penetration levels of less than 1 cm from the core exterior. To monitor for microbial contamination during downstream processing of the permafrost and ground ice cores, a Pseudomonas strain expressing the green fluorescent protein (GFP) was painted on the core exterior prior to processing. Contamination of the processed core interiors with the GFP-expressing strain was not detected by culturing the samples or by PCR to detect the gfp marker gene. These methodologies were quick, were easy to apply, and should help to monitor the exogenous microbiological contamination of pristine permafrost and ground ice samples for downstream culture-dependent and culture-independent microbial analyses. PMID:15691963

  15. Aqueous poly(amidoamine) dendrimer G3 and G4 generations with several interior cores at pHs 5 and 7: a molecular dynamics simulation study.

    PubMed

    Kavyani, Sajjad; Amjad-Iranagh, Sepideh; Modarress, Hamid

    2014-03-27

    Poly(amidoamine) (PAMAM) dendrimers play an important role in drug delivery systems, because the dendrimers are susceptible to gain unique features with modification of their structure such as changing their terminals or improving their interior core. To investigate the core improvement and the effect of core nature on PAMAM dendrimers, we studied two generations G3 and G4 PAMAM dendrimers with the interior cores of commonly used ethylendiamine (EDA), 1,5-diaminohexane (DAH), and bis(3-aminopropyl) ether (BAPE) solvated in water, as an aqueous dendrimer system, by using molecular dynamics simulation and applying a coarse-grained (CG) dendrimer force field. To consider the electrostatic interactions, the simulations were performed at two protonation states, pHs 5 and 7. The results indicated that the core improvement of PAMAM dendrimers with DAH produces the largest size for G3 and G4 dendrimers at both pHs 5 and 7. The increase in the size was also observed for BAPE core but it was not so significant as that for DAH core. By considering the internal structure of dendrimers, it was found that PAMAM dendrimer shell with DAH core had more cavities than with BAPE core at both pHs 5 and 7. Also the moment of inertia calculations showed that the generation G3 is more open-shaped and has higher structural asymmetry than the generation G4. Possessing these properties by G3, specially due to its structural asymmetry, make penetration of water beads into the dendrimer feasible. But for higher generation G4 with its relatively structural symmetry, the encapsulation efficiency for water molecules can be enhanced by changing its core to DAH or BAPE. It is also observed that for the higher generation G4 the effect of core modification is more profound than G3 because the core modification promotes the structural asymmetry development of G4 more significantly. Comparing the number of water beads that penetrate into the PAMAM dendrimers for EDA, DAH, and BAPE cores indicates a significant increase when their cores have been modified with DAH or BAPE and substantiates the effective influence of the core nature in the dendrimer encapsulation efficiency.

  16. Evaluation of Materials and Concepts for Aircraft Fire Protection

    NASA Technical Reports Server (NTRS)

    Anderson, R. A.; Price, J. O.; Mcclure, A. H.; Tustin, E. A.

    1976-01-01

    Woven fiberglass fluted-core simulated aircraft interior panels were flame tested and structurally evaluated against the Boeing 747 present baseline interior panels. The NASA-defined panels, though inferior on a strength-to-weight basis, showed better structural integrity after flame testing, due to the woven fiberglass structure.

  17. Construction of Martian Interior Model

    NASA Astrophysics Data System (ADS)

    Zharkov, V. N.; Gudkova, T. V.

    2005-09-01

    We present the results of extensive numerical modeling of the Martian interior. Yoder et al. in 2003 reported a mean moment of inertia of Mars that was somewhat smaller than the previously used value and the Love number k 2 obtained from observations of solar tides on Mars. These values of k 2 and the mean moment of inertia impose a strong new constraint on the model of the planet. The models of the Martian interior are elastic, while k 2 contains both elastic and inelastic components. We thoroughly examined the problem of partitioning the Love number k 2 into elastic and inelastic components. The information necessary to construct models of the planet (observation data, choice of a chemical model, and the cosmogonic aspect of the problem) are discussed in the introduction. The model of the planet comprises four submodels—a model of the outer porous layer, a model of the consolidated crust, a model of the silicate mantle, and a core model. We estimated the possible content of hydrogen in the core of Mars. The following parameters were varied while constructing the models: the ferric number of the mantle (Fe#) and the sulfur and hydrogen content in the core. We used experimental data concerning the pressure and temperature dependence of elastic properties of minerals and the information about the behavior of Fe(γ-Fe ), FeS, FeH, and their mixtures at high P and T. The model density, pressure, temperature, and compressional and shear velocities are given as functions of the planetary radius. The trial model M13 has the following parameters: Fe#=0.20; 14 wt % of sulfur in the core; 50 mol % of hydrogen in the core; the core mass is 20.9 wt %; the core radius is 1699 km; the pressure at the mantle-core boundary is 20.4 GPa; the crust thickness is 50 km; Fe is 25.6 wt %; the Fe/Si weight ratio is 1.58, and there is no perovskite layer. The model gives a radius of the Martian core within 1600 1820 km while ≥30 mol % of hydrogen is incorporated into the core. When the inelasticity of the Martian interior is taken into account, the Love number k 2 increases by several thousandths; therefore, the model radius of the planetary core increases as well. The prognostic value of the Chandler period of Mars is 199.5 days, including one day due to inelasticity. Finally, we calculated parameters of the equilibrium figure of Mars for the M13 model: J 2 0 = 1.82 × 10-3, J 4 0 = -7.79 × 10-6, e c-m D = 1/242.3 (the dynamical flattening of the core-mantle boundary).

  18. Interior of the Moon

    NASA Technical Reports Server (NTRS)

    Weber, Renee C.

    2013-01-01

    A variety of geophysical measurements made from Earth, from spacecraft in orbit around the Moon, and by astronauts on the lunar surface allow us to probe beyond the lunar surface to learn about its interior. Similarly to the Earth, the Moon is thought to consist of a distinct crust, mantle, and core. The crust is globally asymmetric in thickness, the mantle is largely homogeneous, and the core is probably layered, with evidence for molten material. This chapter will review a range of methods used to infer the Moon's internal structure, and briefly discuss the implications for the Moon's formation and evolution.

  19. Shape Optimization of Cylindrical Shell for Interior Noise

    NASA Technical Reports Server (NTRS)

    Robinson, Jay H.

    1999-01-01

    In this paper an analytic method is used to solve for the cross spectral density of the interior acoustic response of a cylinder with nonuniform thickness subjected to turbulent boundary layer excitation. The cylinder is of honeycomb core construction with the thickness of the core material expressed as a cosine series in the circumferential direction. The coefficients of this series are used as the design variable in the optimization study. The objective function is the space and frequency averaged acoustic response. Results confirm the presence of multiple local minima as previously reported and demonstrate the potential for modest noise reduction.

  20. Physical properties of the planet Mercury

    NASA Technical Reports Server (NTRS)

    Clark, Pamela E.

    1988-01-01

    The global physical properties of Mercury are summarized with attention given to its figure and orbital parameters. The combination of properties suggests that Mercury has an extensive iron-rich core, possibly with a still-functioning dynamo, which is 42 percent of the interior by volume. Mercury's three major axes are comparable in size, indicating that the planet is a triaxial ellipsoid rather than an oblate spheroid. In terms of the domination of its surface by an intermediate plains terrane, it is more Venus- or Mars-like; however, due to the presence of a large metallic magnetic core, its interior may be more earth-like.

  1. Assessing the accuracy of crown biomass equations for the major commercial species of the interior northwest: study plan and preliminary results

    Treesearch

    David L.R. Affleck; Brian R. Turnquist

    2012-01-01

    Fueled by the insistencies of wildfire mitigation, bioenergy development, and carbon sequestration, there is growing demand for reliable characterizations of crown and stem biomass stocks in conifer forests of the Interior Northwest, United States (western Montana, northern Idaho, and eastern Washington). Predictive equations for crown biomass have been developed for...

  2. Persistent effects of fire severity on early successional forests in interior Alaska

    Treesearch

    Aditi Shenoy; Jill F. Johnstone; Eric S. Kasischke; Knut Kielland

    2011-01-01

    There has been a recent increase in the frequency and extent of wildfires in interior Alaska, and this trend is predicted to continue under a warming climate. Although less well documented, corresponding increases in fire severity are expected. Previous research from boreal forests in Alaska and western Canada indicate that severe fire promotes the recruitment of...

  3. Thermal evolution and core formation of planetesimals

    NASA Astrophysics Data System (ADS)

    Suwa, Taichi; Nagahara, Hiroko

    2017-04-01

    Planetesimals did not get an adequate thermal energy by accretion to form large scale magma ocean because of smaller radii, masses, gravity and accretion energy, however, there are various evidences for the presence of core in planetesimals: 4-Vesta has a core and non-magmatic iron meteorites were segregated metal in bodies that did not experience silicate melting. It has been pointed out that accretion time of planetesimals controls melting and differentiation, because short lived nuclides are plausible heat source. Other factors such as radiative cooling from the surface and thermal conductivity, would also affect thermal evolution of planetesimals. Furthermore, percolation of Fe-S melt through silicate matrix is controlled by the porosity and grain size of silicates and dihedral angle between the melt and silicates. Therefore, the interior structure of planetesimals should be considered by taking the accretion, growth, and thermal evolution of the interior simultaneously. We make a numerical simulation with a spherical 1D model on the basis of the model by Neuman, which is a non-stationary heat conduction equation. We specifically pay attention to the process at temperatures between eutectic temperature Fe-FeS (1213K) and silicate solidus (1425K) and the surface tension of the melt that governs percolation. The model contains three free parameters, formation time, accretion duration, and final size of the planetesimals. The results show that the interior structure can be divided to four types: Type A is undifferentiated, Type B is differentiated to core and mantle of which core was formed by Fe-S melt percolation, Type C is partially differentiated to FeS core and mantle, where mantle retains residual Fe metal, and Type D is differentiated to core and mantle by metal separation in silicate magma. Type A would correspond to the parent bodies of chondrites, and Type B (and Type C?) core would be the source of non-magmatic iron meteorites. Type D would be parent bodies for 4 Vesta and angrites. The conditions for the four types of planetesimals are throuly investigated as a function of the three parameters, accretion time, accreting duration, and palnetesimal size. We found that the planetesimal interior is strongly controlled by the formation time: planetesimals formed after 3 Ma after CAIs would be undifferentiated (Type A) regardless of the planetary size, whereas most of them formed within 1 Ma are Type D (differentiated bodies with magmatically formed core). Types B and C bodies are preferentially formed between 1 and 3 Ma after CAIs. Longer accretion duration tends to be resulted in formation of Types A, B and C. The present work predicts the planetesimal interior structure if we know the formation age with the isotopic measurements of samples and the size of the body, which would be a very powerful tool for future explorations of small bodies except for very small (< 20 km) bodies.

  4. Aquifers of Arkansas: protection, management, and hydrologic and geochemical characteristics of groundwater resources in Arkansas

    USGS Publications Warehouse

    Kresse, Timothy M.; Hays, Phillip D.; Merriman, Katherine R.; Gillip, Jonathan A.; Fugitt, D. Todd; Spellman, Jane L.; Nottmeier, Anna M.; Westerman, Drew A.; Blackstock, Joshua M.; Battreal, James L.

    2014-01-01

    The Interior Highlands of western Arkansas has less reported groundwater use than other areas of the State, reflecting a combination of factors. These factors include prevalent and increasing use of surface water, less intensive agricultural uses, lower population and industry densities, lesser potential yield of the resource, and lack of detailed reporting. The overall low yields of aquifers of the Interior Highlands result in domestic supply as the dominant use, with minor industrial, public, and commercial-supply use. Where greater volumes are required for growth of population and industry, surface water is the greatest supplier of water needs in the Interior Highlands. The various aquifers of the Interior Highlands generally occur in shallow, fractured, well-indurated, structurally modified bedrock of this mountainous region of the State, as compared to the relatively flat-lying, unconsolidated sediments of the Coastal Plain. In terms of age from youngest to oldest, the aquifers of the Interior Highlands include: the Arkansas River Valley alluvial aquifer, the Ouachita Mountains aquifer, the Western Interior Plains confining system, the Springfield Plateau aquifer, and the Ozark aquifer. Spatial trends in groundwater geochemistry in the Interior Highlands differ greatly from trends noted for aquifers of the Coastal Plain. In the Coastal Plain, the prevalence of long regional flow paths results in regionally predictable and mappable geochemical changes along the flow paths. In the Interior Highlands, short, topographically controlled flow paths (from hilltops to valleys) within small watersheds represent the predominant groundwater-flow system. As such, dense data coverage from numerous wells would be required to effectively characterize these groundwater basins and define small-scale geochemical changes along any given flow path for aquifers of the Interior Highlands. Changes in geochemistry generally were related to rock type and residence time along individual flow paths. Dominant changes in geochemistry for the Ouachita Mountains aquifer and the Western Interior Plains confining system are attributed to rock/water interaction and changes in redox zonation along the flow path. In these areas, groundwater evolves along flow paths from a calcium- to a sodium-bicarbonate water type with increasing reducing conditions resulting in denitrification, elevated iron and manganese concentrations, and production of methane in the more geochemically evolved and strongest reducing conditions. In the Ozark and Springfield Plateau aquifers, rapid influx of surface-derived contaminants, especially nitrogen, coupled with few to no attenuation processes was attributed to the karst landscape developed on Mississippian- and Ordovician-age carbonate rocks of the Ozark Plateaus. Increasing nitrate concentrations are related to increasing agricultural land use, and areas of mature karst development result in higher nitrate concentrations than areas with less karst features.

  5. 75 FR 21040 - Notice of Determinations Terminating Investigations of Petitions Regarding Eligibility To Apply...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-22

    ...: Freeman Marine Equipment, Inc., Gold Beach, Oregon. TA-W-70,693: Western Electronics, Meridian Idaho. TA-W-70,693A: Western Electronics, Westminster, Colorado. TA-W-70,787: Johnson Controls, Inc., Pulaski...-72,320; Atmel Corporation, Colorado Springs, Colorado. TA-W-72,357: Home Interiors, Inc., Carrollton...

  6. Notice of release for Eagle Germplasm western yarrow (selected germplasm, natural track)

    Treesearch

    Scott M. Lambert; Stephen B. Monsen; Nancy Shaw

    2011-01-01

    The United States Department of Agriculture, Forest Service, Rocky Mountain Research Station; United States Department of the Interior, Bureau of Land Management, Idaho State Office; Utah State University, Agricultural Experiment Station; and University of Idaho, Agricultural Experiment Station, announce the release of a selected germplasm (natural track) of western...

  7. 76 FR 50245 - Gulf of Mexico (GOM), Outer Continental Shelf (OCS), Western Planning Area (WPA), Oil and Gas...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-12

    ... (BOEMRE), Interior. ACTION: Notice of Availability (NOA) of a Final Supplemental Environmental Impact... sale's incremental contribution to the cumulative impacts on environmental and socioeconomic resources... Mexico (GOM), Outer Continental Shelf (OCS), Western Planning Area (WPA), Oil and Gas Lease Sale for the...

  8. Meteorological, snow, streamflow, topographic, and vegetation height data from four western juniper-dominated experimental catchments in southwestern Idaho, USA

    USDA-ARS?s Scientific Manuscript database

    Weather, snow, stream, topographic, and vegetation data are presented from the South Mountain Experimental Catchments. This study site was established in 2007 as a collaborative, long-term research laboratory to address the impacts of western juniper encroachment and treatments in the interior Great...

  9. Maintenance Resources by Building Use for Installations in Germany

    DTIC Science & Technology

    1991-11-01

    125125. .01 0531140 STEEL ( INSULATED ) PAINTED INTERIOR DOOR 124956. .01 0432710 DOUBLE PANE STEEL FIXED WNDW. 1ST FLOOR 124922. .01 1131200 QUARTZ...FINISH 8507. .00 0535400 ALUMINUM DOUBLE ROLL-UP INTERIOR DOOR 8490. .00 0424310 ALUMINUM LOUVERED EXT DOORS 7973. .00 0421340 STEEL ( INSUL CORE) UNPUT...H.P. 0831130 20 1.09 Clay Block (Painted) Interior 0612200 21 1.08 Wall Sink. Stainless Steel 0811F00 22 1.03 Steel (Painted) Exterior Door 0421210 23

  10. Toward a mineral physics reference model for the Moon's core.

    PubMed

    Antonangeli, Daniele; Morard, Guillaume; Schmerr, Nicholas C; Komabayashi, Tetsuya; Krisch, Michael; Fiquet, Guillaume; Fei, Yingwei

    2015-03-31

    The physical properties of iron (Fe) at high pressure and high temperature are crucial for understanding the chemical composition, evolution, and dynamics of planetary interiors. Indeed, the inner structures of the telluric planets all share a similar layered nature: a central metallic core composed mostly of iron, surrounded by a silicate mantle, and a thin, chemically differentiated crust. To date, most studies of iron have focused on the hexagonal closed packed (hcp, or ε) phase, as ε-Fe is likely stable across the pressure and temperature conditions of Earth's core. However, at the more moderate pressures characteristic of the cores of smaller planetary bodies, such as the Moon, Mercury, or Mars, iron takes on a face-centered cubic (fcc, or γ) structure. Here we present compressional and shear wave sound velocity and density measurements of γ-Fe at high pressures and high temperatures, which are needed to develop accurate seismic models of planetary interiors. Our results indicate that the seismic velocities proposed for the Moon's inner core by a recent reanalysis of Apollo seismic data are well below those of γ-Fe. Our dataset thus provides strong constraints to seismic models of the lunar core and cores of small telluric planets. This allows us to propose a direct compositional and velocity model for the Moon's core.

  11. View of western portion of the Republic of Panama on Isthmus of Panama

    NASA Image and Video Library

    1973-08-30

    SL3-27-224 (July-September 1973) --- A vertical view of the western portion of the Republic of Panama on the Isthmus of Panama as photographed from Earth orbit by one of the six lenses of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. This picture was taken with 2443 infrared color film. The large, clear body of water on the north side of the isthmus is Golfo de los Mosquitos, an extension of the Caribbean Sea. The large, partly cloud-covered body of water on the south side of the isthmus is Golfo de Chiriqui, an extension of the Pacific Ocean. Federal agencies participating with NASA on the EREP project are the Department of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observation Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

  12. Movements of juvenile Gyrfalcons from western and interior Alaska following departure from their natal areas

    USGS Publications Warehouse

    McIntyre, Carol L.; Douglas, David C.; Adams, Layne G.

    2009-01-01

    Juvenile raptors often travel thousands of kilometers from the time they leave their natal areas to the time they enter a breeding population. Documenting movements and identifying areas used by raptors before they enter a breeding population is important for understanding the factors that influence their survival. In North America, juvenile Gyrfalcons (Falco rusticolus) are routinely observed outside the species' breeding range during the nonbreeding season, but the natal origins of these birds are rarely known. We used satellite telemetry to track the movements of juvenile Gyrfalcons during their first months of independence. We instrumented nestlings with lightweight satellite transmitters within 10 d of estimated fledging dates on the Seward Peninsula in western Alaska and in Denali National Park (Denali) in interior Alaska. Gyrfalcons spent an average of 41.4 ± 6.1 d (range  =  30–50 d) in their natal areas after fledging. The mean departure date from natal areas was 27 August ± 6.4 d. We tracked 15 individuals for an average of 70.5 ± 28.1 d post-departure; Gyrfalcons moved from 105 to 4299 km during this period and tended to move greater distances earlier in the tracking period than later in the tracking period. Gyrfalcons did not establish temporary winter ranges within the tracking period. We identified several movement patterns among Gyrfalcons, including unidirectional long-distance movements, multidirectional long- and short-distance movements, and shorter movements within a local region. Gyrfalcons from the Seward Peninsula remained in western Alaska or flew to eastern Russia with no movements into interior Alaska. In contrast, Gyrfalcons from Denali remained in interior Alaska, flew to northern and western Alaska, or flew to northern Alberta. Gyrfalcons from both study areas tended to move to coastal, riparian, and wetland areas during autumn and early winter. Because juvenile Gyrfalcons dispersed over a large geographic area and across three international boundaries, conservation efforts should focus on both regional and international scales.

  13. Electrical Investigation of Metal-Olivine Systems and Application to the Deep Interior of Mercury

    NASA Astrophysics Data System (ADS)

    Zhang, Zhou; Pommier, Anne

    2017-12-01

    We report electrical conductivity measurements on metal-olivine systems at about 5 and 6 GPa and up to 1,675°C in order to investigate the electrical properties of core-mantle boundary (CMB) systems. Electrical experiments were conducted in the multianvil apparatus using the impedance spectroscopy technique. The samples are composed of one metal layer (Fe, FeS, FeSi2, or Fe-Ni-S-Si) and one polycrystalline olivine layer, with the metal:olivine ratio ranging from 1:0.7 to 1:9.2. For all samples, we observe that the bulk electrical conductivity increases with temperature from 10-2.5 to 101.8 S/m, which is higher than the conductivity of polycrystalline olivine but lower than the conductivity of the pure metal phase at similar conditions. In some experiments, a conductivity jump is observed at the temperature corresponding to the melting temperature of the metallic phase. Both the metal:olivine ratio and the metal phase geometry control the electrical conductivity of the two-layer samples. By combining electrical results, textural analyses of the samples, and previous studies of the structure and composition of Mercury's interior, we propose an electrical profile of the deep interior of the planet that accounts for a layered CMB-outer core structure. The electrical model agrees with existing conductivity estimates of Mercury's lower mantle and CMB using magnetic observations and thermodynamic calculations, and thus, supports the hypothesis of a layered CMB-outermost core structure in the present-day interior of Mercury. We propose that the layered CMB-outer core structure is possibly electrically insulating, which may influence the planet's structure and cooling history.

  14. Developing and testing a landscape habitat suitability model for fisher (Martes pennanti) in forests of interior northern California

    Treesearch

    W.J. Zielinski; J. R. Dunk; J. S. Yaeger; D. W. LaPlante

    2010-01-01

    The fisher is warranted for protection under the Endangered Species Act in the western United States and, as such, it is especially important that conservation and management actions are based on sound scientific information. We developed a landscape-scale suitability model for interior northern California to predict the probability of detecting fishers and to identify...

  15. Resiliency of an interior ponderosa pine forest to bark beetle infestations following fuel-reduction and forest-restoration treatments

    Treesearch

    Christopher J Fettig; Stephen R. McKelvey

    2014-01-01

    Mechanical thinning and the application of prescribed fire are commonly used to restore fire-adapted forest ecosystems in the western United States. During a 10-year period, we monitored the effects of fuel-reduction and forest-restoration treatments on levels of tree mortality in an interior ponderosa pine, Pinus ponderosa Dougl. ex Laws., forest...

  16. Proceedings: ecology and management of pinyon-juniper communities within the Interior West; 1997 September 15-18; Provo, UT

    Treesearch

    Stephen B. Monsen; Richard Stevens

    1999-01-01

    A symposium held September 15-18,1997, in Provo, UT, and Sanpete County, UT, provided information on the ecology, management, resource values, and restoration of pinyon-juniper communities in the Interior Western United States. The conference was hosted by the USDA Forest Service, Rocky Mountain Research Station and the Utah Division of Wildlife Resources in...

  17. Advanced Structural and Inflatable Hybrid Spacecraft Module

    NASA Technical Reports Server (NTRS)

    Schneider, William C. (Inventor); delaFuente, Horacio M. (Inventor); Edeen, Gregg A. (Inventor); Kennedy, Kriss J. (Inventor); Lester, James D. (Inventor); Gupta, Shalini (Inventor); Hess, Linda F. (Inventor); Lin, Chin H. (Inventor); Malecki, Richard H. (Inventor); Raboin, Jasen L. (Inventor)

    2001-01-01

    An inflatable module comprising a structural core and an inflatable shell, wherein the inflatable shell is sealingly attached to the structural core. In its launch configuration, the wall thickness of the inflatable shell is collapsed by vacuum. Also in this configuration, the inflatable shell is collapsed and efficiently folded around the structural core. Upon deployment, the wall thickness of the inflatable shell is inflated; whereby the inflatable shell itself, is thereby inflated around the structural core, defining therein a large enclosed volume. A plurality of removable shelves are arranged interior to the structural core in the launch configuration. The structural core also includes at least one longeron that, in conjunction with the shelves, primarily constitute the rigid, strong, and lightweight load-bearing structure of the module during launch. The removable shelves are detachable from their arrangement in the launch configuration so that, when the module is in its deployed configuration and launch loads no longer exist, the shelves can be rearranged to provide a module interior arrangement suitable for human habitation and work. In the preferred embodiment, to provide efficiency in structural load paths and attachments, the shape of the inflatable shell is a cylinder with semi-toroidal ends.

  18. Inflatable Vessel and Method

    NASA Technical Reports Server (NTRS)

    Raboin, Jasen L. (Inventor); Valle, Gerard D. (Inventor); Edeen, Gregg A. (Inventor); delaFuente, Horacio M. (Inventor); Schneider, William C. (Inventor); Spexarth, Gary R. (Inventor); Pandya, Shalini Gupta (Inventor); Johnson, Christopher J. (Inventor)

    2003-01-01

    An inflatable module comprising a structural core and an inflatable shell, wherein the inflatable shell is sealingly attached to the structural core. In its launch or pre-deployed configuration, the wall thickness of the inflatable shell is collapsed by vacuum. Also in this configuration, the inflatable shell is collapsed and efficiently folded around the structural core. Upon deployment, the wall thickness of the inflatable shell is inflated; whereby the inflatable shell itself, is thereby inflated around the structural core, defining therein a large enclosed volume. A plurality of removable shelves are arranged interior to the structural core in the launch configuration. The structural core also includes at least one longeron that, in conjunction with the shelves, primarily constitute the rigid, strong, and lightweight load-bearing structure of the module during launch. The removable shelves are detachable from their arrangement in the launch configuration so that, when the module is in its deployed configuration and launch loads no longer exist, the shelves can be rearranged to provide a module interior arrangement suitable for human habitation and work. In the preferred embodiment, to provide efficiency in structural load paths and attachments, the shape of the inflatable shell is a cylinder with semi-toroidal ends.

  19. 76 FR 49764 - Information Collection Request Extension Submitted to the Office of Management and Budget (OMB...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-11

    ... its APD to properly perform its function of marketing a limited amount of Federal hydropower. Western... the Federal reclamation program.\\4\\ The basic principle of the Reclamation Act of 1902 was the United... the power marketing functions from the Department of the Interior to Western.\\10\\ Pursuant to this...

  20. Aspen: Ecology and management in the western United States

    Treesearch

    Norbert V. DeByle; Robert P. Winokur

    1985-01-01

    Information about the biology, ecology, and management of quaking aspen on the mountains and plateaus of the interior western United States, and to a lesser extent, Canada, is summarized and discussed. The biology of aspen as a tree species, community relationships in the aspen ecosystem, environments, and factors affecting aspen forests are reviewed. The resources...

  1. Detecting depth gradients in the mid-Cretaceous Western Interior Seaway

    NASA Astrophysics Data System (ADS)

    Bryant, R.

    2017-12-01

    Multivariate data sets can be simplified using techniques like ordination and detrended correspondence analysis to identify important ecological gradients such as water depth, and thus provide insight into the environmental distribution of species (Patzkowsky & Holland, 2012). Here, these methods will be applied to abundance data of foraminiferal assemblages from the Western Interior Seaway through the Cenomanian/Turonian boundary ( 94-93 Ma). Through this interval the seaway experienced rapid and abrupt environmental and oceanographic changes, including the onset of Oceanic Anoxic Event 2 (OAE2) and peak transgression. The intense ocean and biosphere changes are well documented in the WIS, but the effect of OAE2 coupled with rising sea level on foraminiferal communities across the seaway is still poorly understood.

  2. Research plan for lands administered by the U.S. Department of the Interior in the Interior Columbia Basin and Snake River Plateau

    USGS Publications Warehouse

    Beever, Erik A.; Pyke, David A.

    2002-01-01

    The research strategy focuses on disturbance processes and events that have been the primary drivers of change, to provide a predictive model for future changes. These drivers include fire, nonnative plants, herbivory, roads and associated human influences, and climate change. Whereas management in the western United States has striven to move from an inefficient species-based approach to a habitat-based approach, the plan focuses on ecosystem function and ecological processes as critical measures of habitat response. Because of the large amount and contiguity of public lands in the western United States, the region presents both a compelling opportunity to implement landscape-level science and a challenge to underst

  3. The exploration of the lunar interior using torsional oscillations

    NASA Astrophysics Data System (ADS)

    Gudkova, T. V.; Zharkov, V. N.

    2002-08-01

    The diagnostic capabilities of the torsional oscillations for probing the structure of the interiors of the Moon are investigated. Models with no core, a liquid core, and a solid core are considered. The profiles of compressional and shear wave velocities, VP and VS, for the lunar interior estimated by Bills and Ferrari (J. Geophys. Res. 82 (1977) 1306), Goins et al. (J. Geophys. Res. 86 (1981b) 5061) and Nakamura (J. Geophys. Res. 8 (1983) 677) from the Apollo lunar seismic network are used. For all these models the periods of torsional oscillations for fundamental modes ℓ=2-100 and four overtones have been calculated. The derivatives of the dimensionless eigenfrequency with respect to the dimensionless shear modulus and density are calculated and tabulated for use. These data can be used for the determination of corrections to the model density and shear modulus distributions due to their small change. The damping of torsional oscillations is also studied. Several trial distributions of the dissipative function Q as a function of radius are considered. It is shown, that the torsional modes with ℓ⩾7, n=0 can be recorded. These modes provide information on the external layers down to about 500 km depth.

  4. Rapid Middle Eocene temperature change in western North America

    NASA Astrophysics Data System (ADS)

    Methner, Katharina; Mulch, Andreas; Fiebig, Jens; Wacker, Ulrike; Gerdes, Axel; Graham, Stephan A.; Chamberlain, C. Page

    2016-09-01

    Eocene hyperthermals are among the most enigmatic phenomena of Cenozoic climate dynamics. These hyperthermals represent temperature extremes superimposed on an already warm Eocene climate and dramatically affected the marine and terrestrial biosphere, yet our knowledge of temperature and rainfall in continental interiors is still rather limited. We present stable isotope (δ18O) and clumped isotope temperature (Δ47) records from a middle Eocene (41 to 40 Ma) high-elevation mammal fossil locality in the North American continental interior (Montana, USA). Δ47 paleotemperatures of soil carbonates delineate a rapid +9/-11 °C temperature excursion in the paleosol record. Δ47 temperatures progressively increase from 23 °C ± 3 °C to peak temperatures of 32 °C ± 3 °C and subsequently drop by 11 °C. This hyperthermal event in the middle Eocene is accompanied by low δ18O values and reduced pedogenic carbonate concentrations in paleosols. Based on laser ablation U/Pb geochronology of paleosol carbonates in combination with magnetostratigraphy, biostratigraphy, stable isotope, and Δ47 evidence, we suggest that this pronounced warming event reflects the Middle Eocene Climatic Optimum (MECO) in western North America. The terrestrial expression of northern hemisphere MECO in western North America appears to be characterized by warmer and wetter (sub-humid) conditions, compared to the post-MECO phase. Large and rapid shifts in δ18O values of precipitation and pedogenic CaCO3 contents parallel temperature changes, indicating the profound impact of the MECO on atmospheric circulation and rainfall patterns in the western North American continental interior during this transient warming event.

  5. Origins of pressure-induced protein transitions.

    PubMed

    Chalikian, Tigran V; Macgregor, Robert B

    2009-12-18

    The molecular mechanisms underlying pressure-induced protein denaturation can be analyzed based on the pressure-dependent differences in the apparent volume occupied by amino acids inside the protein and when they are exposed to water in an unfolded conformation. We present here an analysis for the peptide group and the 20 naturally occurring amino acid side chains based on volumetric parameters for the amino acids in the interior of the native state, the micelle-like interior of the pressure-induced denatured state, and the unfolded conformation modeled by N-acetyl amino acid amides. The transfer of peptide groups from the protein interior to water becomes increasingly favorable as pressure increases. Thus, solvation of peptide groups represents a major driving force in pressure-induced protein denaturation. Polar side chains do not appear to exhibit significant pressure-dependent changes in their preference for the protein interior or solvent. The transfer of nonpolar side chains from the protein interior to water becomes more unfavorable as pressure increases. We conclude that a sizeable population of nonpolar side chains remains buried inside a solvent-inaccessible core of the pressure-induced denatured state. At elevated pressures, this core may become packed almost as tightly as the interior of the native state. The presence and partial disappearance of large intraglobular voids is another driving force facilitating pressure-induced denaturation of individual proteins. Our data also have implications for the kinetics of protein folding and shed light on the nature of the folding transition state ensemble.

  6. Origins and spread of fluted-point technology in the Canadian Ice-Free Corridor and eastern Beringia.

    PubMed

    Smith, Heather L; Goebel, Ted

    2018-04-17

    Fluted projectile points have long been recognized as the archaeological signature of early humans dispersing throughout the Western Hemisphere; however, we still lack a clear understanding of their appearance in the interior "Ice-Free Corridor" of western Canada and eastern Beringia. To solve this problem, we conducted a geometric morphometric shape analysis and a phylogenetic analysis of technological traits on fluted points from the archaeological records of northern Alaska and Yukon, in combination with artifacts from further south in Canada, the Great Plains, and eastern United States to investigate the plausibility of historical relatedness and evolutionary patterns in the spread of fluted-point technology in the latest Pleistocene and earliest Holocene. Results link morphologies and technologies of Clovis, certain western Canadian, and northern fluted points, suggesting that fluting technology arrived in the Arctic from a proximate source in the interior Ice-Free Corridor and ultimately from the earliest populations in temperate North America, complementing new genomic models explaining the peopling of the Americas.

  7. The Cenomanian-Turonian Oceanic Anoxic Event 2 (OAE2) in the Western Interior US and Gulf of Mexico: Decoupled Black Shale Deposition and Carbon Isotope Excursion

    NASA Astrophysics Data System (ADS)

    Lowery, C.; Snedden, J.; Cunningham, R.; Barrie, C.; Leckie, R. M.

    2016-12-01

    The largest carbon isotope excursions (CIEs) of the Cretaceous are associated with widespread evidence for marine anoxia and have been termed Oceanic Anoxic Events (OAEs). OAEs were originally thought to be globally-correlative intervals of black shales, but black shale deposition is an inherently provincial phenomenon driven by local conditions, and black shales associated with individual OAEs are often slightly diachronous and can be absent in some regions. Workers currently favor a definition of OAEs that is focused on the positive carbon isotope excursion driven by the global burial of organic matter and resulting carbon cycle perturbation; i.e., recording the global, rather than local, changes. While this is certainly the best way to define a global event, differences in the expression of the event between regions can be used to study the nature of the event itself. The greater Gulf of Mexico region in southern North America offers an excellent example of the diachroneity of black shale deposition and anoxia during one of the largest OAEs, the Cenomanian-Turonian OAE2. The Western Interior Seaway (WIS), flooded the interior of North America from the Gulf of Mexico up through the Canadian Arctic. In Texas and elsewhere across the WIS, high marine organic matter deposition and proxies for anoxia (especially benthic foraminifera and redox sensitive trace metals) are common before the event, but decrease at its onset, and in some places increase again after the event. Further south, across the Mexican shelf, deeper shelf environments remain dysoxic/anoxic through the event, while several carbonate platforms remain oxygenated during the event, but drown and record anoxic bottom waters shortly afterward. Here, we present new bulk carbonate and organic carbon isotopes and planktic and benthic foraminiferal populations from a 90 m core in southern Mississippi, USA, to present the first record of OAE2 from the northern Gulf of Mexico. In particular, we use foraminiferal populations to study the local redox conditions before, during, and after OAE2, and compare them to records from Mexico and across the WIS in order to understand regional patterns of environmental change, their underlying paleoclimatic and paleoceanographic drivers, and what this reveals about the overall development of OAE2.

  8. Toward a mineral physics reference model for the Moon’s core

    PubMed Central

    Antonangeli, Daniele; Morard, Guillaume; Schmerr, Nicholas C.; Komabayashi, Tetsuya; Krisch, Michael; Fiquet, Guillaume; Fei, Yingwei

    2015-01-01

    The physical properties of iron (Fe) at high pressure and high temperature are crucial for understanding the chemical composition, evolution, and dynamics of planetary interiors. Indeed, the inner structures of the telluric planets all share a similar layered nature: a central metallic core composed mostly of iron, surrounded by a silicate mantle, and a thin, chemically differentiated crust. To date, most studies of iron have focused on the hexagonal closed packed (hcp, or ε) phase, as ε-Fe is likely stable across the pressure and temperature conditions of Earth’s core. However, at the more moderate pressures characteristic of the cores of smaller planetary bodies, such as the Moon, Mercury, or Mars, iron takes on a face-centered cubic (fcc, or γ) structure. Here we present compressional and shear wave sound velocity and density measurements of γ-Fe at high pressures and high temperatures, which are needed to develop accurate seismic models of planetary interiors. Our results indicate that the seismic velocities proposed for the Moon’s inner core by a recent reanalysis of Apollo seismic data are well below those of γ-Fe. Our dataset thus provides strong constraints to seismic models of the lunar core and cores of small telluric planets. This allows us to propose a direct compositional and velocity model for the Moon’s core. PMID:25775531

  9. Appendix 3: Western mountain initiative synthesis. Response of western mountain ecosystems to climatic variability and change: a synthesis from the western mountain initiative

    Treesearch

    Crystal L. Raymond

    2012-01-01

    Alaskan forests cover one-third of the state’s 52 million ha of land (Parson et al. 2001), and are regionally and globally significant. Ninety percent of Alaskan forests are classified as boreal, representing 4 percent of the world’s boreal forests, and are located throughout interior and south-central Alaska (fig. A1-1). The remaining 10 percent of Alaskan forests are...

  10. Wellsite, laboratory, and mathematical techniques for determining sorbed gas content of coals and gas shales utilizing well cuttings

    USGS Publications Warehouse

    Newell, K.D.

    2007-01-01

    Drill cuttings can be used for desorption analyses but with more uncertainty than desorption analyses done with cores. Drill cuttings are not recommended to take the place of core, but in some circumstances, desorption work with cuttings can provide a timely and economic supplement to that of cores. The mixed lithologic nature of drill cuttings is primarily the source of uncertainty in their analysis for gas content, for it is unclear how to apportion the gas generated from both the coal and the dark-colored shale that is mixed in usually with the coal. In the Western Interior Basin Coal Basin in eastern Kansas (Pennsylvanian-age coals), dark-colored shales with normal (??? 100 API units) gamma-ray levels seem to give off minimal amounts of gas on the order of less than five standard cubic feet per ton (scf/ton). In some cuttings analyses this rule of thumb for gas content of the shale is adequate for inferring the gas content of coals, but shales with high-gamma-ray values (>150 API units) may yield several times this amount of gas. The uncertainty in desorption analysis of drill cuttings can be depicted graphically on a diagram identified as a "lithologic component sensitivity analysis diagram." Comparison of cuttings desorption results from nearby wells on this diagram, can sometimes yield an unique solution for the gas content of both a dark shale and coal mixed in a cuttings sample. A mathematical solution, based on equating the dry, ash-free gas-contents of the admixed coal and dark-colored shale, also yields results that are correlative to data from nearby cores. ?? 2007 International Association for Mathematical Geology.

  11. Teaching a Non-Western Core Program: The Development of Integrated Skills.

    ERIC Educational Resources Information Center

    Posey, John P.

    1984-01-01

    Describes the use of various learning methods in the Non-Western core of St. Joseph's College's interdisciplinary general education program, including extemporaneous speeches and individual role-playing exercises, extemporaneous group presentations of interviews and political demonstrations, simulation projects recreating a Chinese People's…

  12. Assessing carbon storage in western U.S. ecosystems

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2013-01-01

    Western U.S. ecosystems have the capacity to sequester about 91 million metric tons of carbon per year, according to a report released 5 December by the Department of the Interior. Entitled "Baseline and Projected Future Carbon Storage and Greenhouse-Gas Fluxes in Ecosystems of the Western United States" and written by U.S. Geological Survey (USGS) scientists, the report came out of a congressionally mandated study. It examines how much carbon can be stored naturally through biological activity in various ecosystems, including forests, grasslands, and wetlands, in the western United States, from the Rocky Mountains to the Pacific.

  13. Dislocation models of interseismic deformation in the western United States

    USGS Publications Warehouse

    Pollitz, F.F.; McCrory, P.; Svarc, J.; Murray, J.

    2008-01-01

    The GPS-derived crustal velocity field of the western United States is used to construct dislocation models in a viscoelastic medium of interseismic crustal deformation. The interseismic velocity field is constrained by 1052 GPS velocity vectors spanning the ???2500-km-long plate boundary zone adjacent to the San Andreas fault and Cascadia subduction zone and extending ???1000 km into the plate interior. The GPS data set is compiled from U.S. Geological Survey campaign data, Plate Boundary Observatory data, and the Western U.S. Cordillera velocity field of Bennett et al. (1999). In the context of viscoelastic cycle models of postearthquake deformation, the interseismic velocity field is modeled with a combination of earthquake sources on ???100 known faults plus broadly distributed sources. Models that best explain the observed interseismic velocity field include the contributions of viscoelastic relaxation from faulting near the major plate margins, viscoelastic relaxation from distributed faulting in the plate interior, as well as lateral variations in depth-averaged rigidity in the elastic lithosphere. Resulting rigidity variations are consistent with reduced effective elastic plate thickness in a zone a few tens of kilometers wide surrounding the San Andreas fault (SAF) system. Primary deformation characteristics are captured along the entire SAF system, Eastern California Shear Zone, Walker Lane, the Mendocino triple junction, the Cascadia margin, and the plate interior up to ???1000 km from the major plate boundaries.

  14. Historical forest structure, composition, and spatial pattern in dry conifer forests of the western Blue Mountains, Oregon

    Treesearch

    Derek J. Churchill; Gunnar C. Carnwath; Andrew J. Larson; Sean A. Jeronimo

    2017-01-01

    In frequent-fire forests of the interior Western United States, historical (prefire suppression) conditions are often used as a reference to set management objectives, guide prescriptions, and monitor treatment effectiveness. We quantified the historical size, density, composition, and spatial patterns of dry mixed-conifer forests in the Blue Mountains of Oregon to...

  15. Role of nonmarket economic values in benefit-cost analysis of public forest management.

    Treesearch

    Cindy Sorg Swanson; John B. Loomis

    1996-01-01

    Recreation in the Pacific Northwest is a valuable resource. A method is described that translates recreation on USDA Forest Service and U.S. Department of Interior Bureau of Land Management lands in northern California, western Oregon, and western Washington into economic value. By assigning recreation to land use type (using the Forest Service recreation opportunity...

  16. Pine Engraver, Ips pini, in the Western United States (FIDL)

    Treesearch

    Sandra J. Kegley; R. Ladd Livingston; Kenneth E. Gibson

    1997-01-01

    The pine engraver, Ips pini (Say), is one of the most common and widely distributed bark beetles in North America. It occurs from southern Appalachia north to Maine and Quebec, westward across the northern United States and Canada, into the interior of Alaska, throughout the Pacific Coast States and the Rocky Mountain region, to northern Mexico. In the western United...

  17. Prediction of delayed mortality of fire-damaged ponderosa pine following prescribed fires in eastern Oregon, USA.

    Treesearch

    Walter G. Thies; Douglas J. Westlina; Mark Loewen; Greg Brenner

    2006-01-01

    Prescribed burning is a management tool used to reduce fuel loads in western interior forests. Following a burn, managers need the ability to predict the mortality of individual trees based on easily observed characteristics. A study was established in six stands of mixed-age ponderosa pine (Pinus ponderosa Dougl. ex Laws.) with scattered western...

  18. 78 FR 24435 - Notice of Availability of the Proposed Notice of Sale (NOS) for Western Gulf of Mexico Planning...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-25

    ... of the Proposed Notice of Sale (NOS) for Western Gulf of Mexico Planning Area (WPA) Outer Continental Shelf (OCS) Oil and Gas Lease Sale 233 (WPA Sale 233) AGENCY: Bureau of Ocean Energy Management (BOEM), Interior. ACTION: Notice of Availability of the Proposed Notice of WPA Sale 233 SUMMARY: BOEM announces the...

  19. Monitoring the deep western boundary current in the western North Pacific by echo intensity measured with lowered acoustic Doppler current profiler

    NASA Astrophysics Data System (ADS)

    Komaki, Kanae; Nagano, Akira

    2018-05-01

    Oxidation of iron and manganese ions is predominant in the oxygen-rich deep western boundary current (DWBC) within the Pacific Ocean. By the faster removal of particulate iron hydroxide and manganese oxide, densities of the particulate matters are considered to be lower in the DWBC than the interior region. To detect the density variation of suspended particles between the DWBC and interior regions, we analyzed echo intensity (EI) measured in the western North Pacific by hydrographic casts with a 300 kHz lowered acoustic Doppler current profiler (LADCP) in a whole water column. At depths greater than 3000 m ( 3000 dbar), EI is almost uniformly low between 12°N and 30°N but peaks sharply from 30°N to 35°N to a maximum north of 35°N. EI is found to be anomalously low in the DWBC compared to the background distribution. The DWBC pathways are identifiable by the low EI and high dissolved oxygen concentration. EI data by LADCPs and other acoustic instruments may be used to observe the temporal variations of the DWBC pathways.

  20. Brittle Deformation in the Ordos Basin in response to the Mesozoic destruction of the North China Craton

    NASA Astrophysics Data System (ADS)

    Wang, Q.; Jiang, L.

    2012-12-01

    Craton is continental block that has been tectonically stable since at least Proterozoic. Some cratons, however, become unstable for some geodynamic reasons. The North China Craton (NCC) is an example. Structure geological, geochemical, and geophysical works have revealed that the NCC was destructed in Cretaceous and that lithosphere thickness beneath the eastern NCC were thinned by 120 km. The present study will focus on deformation of the western NCC, and to understand the effect of the Mesozoic destruction of the North China Craton (NCC). Structural partitioning of the Ordos Basin, which is located in the western NCC, from the eastern NCC occurred during the Mesozoic. Unlike the eastern NCC where many Cretaceous metamorphic core complexes developed, sedimentary cover of the NCC remains nearly horizontal and deformation is manifested by joint. We visited 216 sites of outcrops and got 1928 joints measurements, among which 270 from Jurassic sandstones, 1378 from the Upper Triassic sandstones, 124 from the Middle and Lower Triassic sandstones, and 156 from Paleozoic sandstones. In the interior of the Ordos Basin, joints developed quite well in the Triassic strata, while joints in the Jurassic stata developed weakly and no joint in the Cretaceous strata. The Mesozoic stratigraphic thickness are: 1000 meters for the Lower Triassic, the Middle Triassic sandstone with thickness of 800 meters, 3000 meters for the Upper Triassic, 4000 meters for the Jurassic, and 1100 meters for the Lower Cretaceous. The vertical difference in joint development might be related to the burying depth of the strata: the higher the strata, the smaller the lithostatic stress, and then the weaker the joint. Joints in all stratigraphic levels showed a similar strain direction with the sigma 1 (the maximum pressure stress) vertical and the sigma 3 (the minimum pressure stress) horizontal and running N-S. The unconformity below the Cretaceous further indicates that joints in Jurassic and Triassic strata were developed in the beginning of Cretaceous. It seems that the western NCC experienced only uplift that recorded a weak N-S extension and E-W compression during the Early Cretaceous when the NCC experienced destruction. Conclusions: 1. The Cretaceous uplift ceased the "natural test of mechanical property" of the strata in the Ordos Basin. The difference in burying depth of the strata caused the vertical difference in joints development. 2. Joints in the interior of the Ordos Basin indicate a N-S extension and E-W compression with the sigma 1 vertical in the Early Cretaceous, as implying a regional uplift in the western NCC during its Mesozoic destruction.

  1. Fleas (Siphonaptera) of the Allegheny woodrat (Neotoma magister) in West Virginia with comments on host specificity

    USGS Publications Warehouse

    Castleberry, S.B.; Castleberry, N.L.; Wood, P.B.; Ford, W.M.; Mengak, M.T.

    2003-01-01

    Previous research has indicated fewer host-specific ectoparasites on woodrats of the eastern United States as compared to western woodrat species. The Allegheny woodrat (Neotoma magister) is a species of conservation concern that is associated with rocky habitats in the Appalachian and Interior Highland regions in the eastern United States. We examined Allegheny woodrat flea parasites in the core of the distribution to further elucidate patterns of ectoparasite host specificity in woodrats of the eastern United States. Of 346 fleas collected from 62 Allegheny woodrats, all but 1 were identified as Orchopeas pennsylvanicus. The single exception was a male Epitedia cavernicola, which represents only the second collection of this species from West Virginia. Unlike the eastern woodrat (Neotoma floridana), which hosts a variety of generalist flea parasites, Allegheny woodrats in our study were host to only 2 flea species, both of which are host specific to woodrats. We suggest that flea host specificity may be related to the specific habitat requirements of this species.

  2. The Spectrum of Torsional Oscillations of the Moon

    NASA Astrophysics Data System (ADS)

    Gudkova, T. V.; Zharkov, V. N.

    2000-11-01

    The diagnostic potentialities of the torsional oscillations for probing the structure of the interiors of the Moon are investigated. Models with no core, a liquid core, and a solid core are considered. The profiles of compressional and shear wave velocities V_P and V_S for the lunar interior estimated by Bills and Ferrari (1977), Goins et al. (1981), and Nakamura (1983) from the Apollo lunar seismic network are used. For all these models, the periods of torsional oscillations for n = 2-100 and four overtones have been calculated. The derivatives of the dimensionless eigenfrequency with respect to the dimensionless shear modulus and density are calculated and tabulated for use. These data can be used to determine corrections to the model density and shear modulus distributions due to their small change. The damping of torsional oscillations is studied. Several trial radial distributions of the dissipative function Q are considered.

  3. Innovative Retrofit Insulation Strategies for Concrete Masonry Foundations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huelman, P.; Goldberg, L.; Jacobson, R.

    This study was designed to test a new approach for foundation insulation retrofits, with the goal of demonstrating improved moisture control, improved occupant comfort, and reduced heat loss. Because conducting experimental research on existing below-grade assemblies is very difficult, most of the results are based on simulations. The retrofit approach consists of filling open concrete block cores with an insulating material and adding R-10 exterior insulation that extends 1 ft below grade. The core fill is designed to improve the R-value of the foundation wall and increase the interior wall surface temperature, but more importantly to block convection currents thatmore » could otherwise increase moisture loads on the foundation wall and interior space. The exterior insulation significantly reduces heat loss through the most exposed part of the foundation and further increases the interior wall surface temperature. This improves occupant comfort and decreases the risk of condensation. Such an insulation package avoids the full-depth excavation necessary for exterior insulation retrofits, reduces costs, and eliminates the moisture and indoor air quality risks associated with interior insulation retrofits. Retrofit costs for the proposed approach were estimated at roughly half those of a full-depth exterior insulation retrofit.« less

  4. Organic petrology of the Aptian-age section in the downdip Mississippi Interior Salt Basin, Mississippi, USA: Observations and preliminary implications for thermal maturation history

    USGS Publications Warehouse

    Valentine, Brett J.; Hackley, Paul C.; Enomoto, Catherine B.; Bove, Alana M.; Dulong, Frank T.; Lohr, Celeste D.; Scott, Krystina R.

    2014-01-01

    This study identifies a thermal maturity anomaly within the downdip Mississippi Interior Salt Basin (MISB) of southern Mississippi, USA, through examination of bitumen reflectance data from Aptian-age strata (Sligo Formation, Pine Island Shale, James Limestone, and Rodessa Formation). U.S. Geological Survey (USGS) reconnaissance investigations conducted in 2011–2012 examined Aptian-age thermal maturity trends across the onshore northern Gulf of Mexico region and indicated that the section in the downdip MISB is approaching the wet gas/condensate window (Ro~1.2%). A focused study in 2012–2013 used 6 whole core, one sidewall core, and 49 high-graded cutting samples (depth range of 13,000–16,500 ft [3962.4–5029.2 m] below surface) collected from 15 downdip MISB wells for mineralogy, fluid inclusion, organic geochemistry, and organic petrographic analysis. Based on native solid bitumen reflectance (Ro generally > 0.8%; interpreted to be post-oil indigenous bitumens matured in situ), Ro values increase regionally across the MISB from the southeast to the northwest. Thermal maturity in the eastern half of the basin (Ro range 1.0 to 1.25%) appears to be related to present-day burial depth and shows a gradual increase with respect to depth. To the west, thermal maturity continues to increase even as the Aptian section shallows structurally on the Adams County High (Ro range 1.4 to > 1.8%). After evaluating the possible thermal agents responsible for increasing maturity at shallower depths (i.e., igneous activity, proximity to salt, variations in regional heat flux, and uplift), we tentatively propose that either greater paleoheat flow or deeper burial coupled with uplift in the western part of the MISB could be responsible for the thermal maturity anomaly. Further research and additional data are needed to determine the cause(s) of the thermal anomaly.

  5. Electron cyclotron heating and core intrinsic rotation reversal in DIII-D

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grassie, J. S. de, E-mail: degrassie@fusion.gat.com; Boedo, J. A.; Grierson, B. A.

    2015-12-10

    The effect of electron cyclotron heating (ECH) on the intrinsic rotation profile in DIII-D is shown experimentally. Former DIII-D experiments have shown that ECH tends to cause an interior reduction in the normally co-Ip directed intrinsic rotation profile, and this core rotation can be fully reversed to the opposite direction. This effect is due to a turbulent rearrangement of the interior rotation profile. Here, we show results that there is more than one mechanism causing this. We compare two low density L-mode discharges where the only operational difference is the location of the ECH deposition. At low ECH power, comparablemore » to the Ohmic power, the primary change is in the q-profile accompanied by a reversal of the core intrinsic rotation direction for the more off-axis deposition. The change in the shear of the q-profile fits well with a recent theoretical prediction for this rotation reversal. At higher ECH power, the primary change is in the core electron temperature, Te, accompanied by a hollowing of the rotation profile near the magnetic axis. This effect appears to be due to the change in electron collisionality, consistent with another theoretical, gyrokinetic prediction. The variety of phenomena that could allow ECH to modify the intrinsic rotation profile give some expectation that regions of large velocity shear in the interior could be generated, with the possibility of triggering internal transport barriers.« less

  6. Habitat characterization of western hoolock gibbons Hoolock hoolock by examining home range microhabitat use.

    PubMed

    Akers, Alice A; Anwarul Islam, Md; Nijman, Vincent

    2013-10-01

    Conserving a species depends on an understanding of its habitat requirements. Primatologists often characterize the habitat requirements of primates using macroscale population-based approaches relying on correlations between habitat attributes and population abundances between sites with varying levels of disturbance. This approach only works for species spread between several populations. The populations of some primates do not fulfill these criteria, forcing researchers to rely on individual-based (microscale) rather than population-based approaches for habitat characterization. We examined the reliability of using micro-scale habitat characterizations by studying the microhabitat preferences of a group of wild western hoolock gibbons (Hoolock hoolock) in order to compare our results to the habitat preferences of western hoolock gibbons identified during a macroscale study of populations across Bangladesh. We used stepwise discriminant analysis to differentiate between the areas of low, medium, and high usage based on microhabitat characteristics (tree species availability, altitude, canopy connection, distance from forest edge, and levels of human disturbance). The gibbons used interior forest habitat with low food tree availability most frequently for sleeping and socializing, and used edge habitat containing high food tree availability for medium periods for feeding. These results indicate that the gibbons prefer interior forest but are frequently forced to visit the forest edge to feed. Therefore, the optimal habitat would be interior forest away from human disturbance with high sleeping-tree and feeding-tree availability. These habitat preferences are consistent with the habitat attributes of Bangladesh's largest remaining western hoolock gibbon populations, which live in areas containing low agricultural encroachment and high food-tree availability. Microhabitat use studies can be used to characterize the habitat requirements of a species, but should include multiple scales of analysis wherever possible.

  7. Sediment Core Descriptions: R/V KANA KEOKI 1972 Cruise, Eastern and Western Pacific Ocean,

    DTIC Science & Technology

    1976-06-01

    of ship tracks and coring stations are shown. Corrected satellite navigation-determined coordinates for each coring operation are indicated, and water depth, length of core, and age of oldest sediment in the cores are given.

  8. Equivalent Circuit Parameter Calculation of Interior Permanent Magnet Motor Involving Iron Loss Resistance Using Finite Element Method

    NASA Astrophysics Data System (ADS)

    Yamazaki, Katsumi

    In this paper, we propose a method to calculate the equivalent circuit parameters of interior permanent magnet motors including iron loss resistance using the finite element method. First, the finite element analysis considering harmonics and magnetic saturation is carried out to obtain time variations of magnetic fields in the stator and the rotor core. Second, the iron losses of the stator and the rotor are calculated from the results of the finite element analysis with the considerations of harmonic eddy current losses and the minor hysteresis losses of the core. As a result, we obtain the equivalent circuit parameters i.e. the d-q axis inductance and the iron loss resistance as functions of operating condition of the motor. The proposed method is applied to an interior permanent magnet motor to calculate the characteristics based on the equivalent circuit obtained by the proposed method. The calculated results are compared with the experimental results to verify the accuracy.

  9. Present-Day Mars' Seismicity Predicted From 3-D Thermal Evolution Models of Interior Dynamics

    NASA Astrophysics Data System (ADS)

    Plesa, A.-C.; Knapmeyer, M.; Golombek, M. P.; Breuer, D.; Grott, M.; Kawamura, T.; Lognonné, P.; Tosi, N.; Weber, R. C.

    2018-03-01

    The Interior Exploration using Seismic Investigations, Geodesy and Heat Transport mission, to be launched in 2018, will perform a comprehensive geophysical investigation of Mars in situ. The Seismic Experiment for Interior Structure package aims to detect global and regional seismic events and in turn offer constraints on core size, crustal thickness, and core, mantle, and crustal composition. In this study, we estimate the present-day amount and distribution of seismicity using 3-D numerical thermal evolution models of Mars, taking into account contributions from convective stresses as well as from stresses associated with cooling and planetary contraction. Defining the seismogenic lithosphere by an isotherm and assuming two end-member cases of 573 K and the 1073 K, we determine the seismogenic lithosphere thickness. Assuming a seismic efficiency between 0.025 and 1, this thickness is used to estimate the total annual seismic moment budget, and our models show values between 5.7 × 1016 and 3.9 × 1019 Nm.

  10. LPT. EBOR (TAN646) interior, installing reactor in STF pool ("vault"). ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    LPT. EBOR (TAN-646) interior, installing reactor in STF pool ("vault"). Pressure vessel shows core barrel and outlet nozzle (next to man below) to inner duct weld, which is prepared and in position for stress relieving. Camera facing southeast. Photographer: Comiskey. Date: January 20, 1965. INEEL negative no. 65-239 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  11. The Juno Mission to Jupiter

    NASA Technical Reports Server (NTRS)

    Grammier, Richard S.

    2006-01-01

    Origin: Determine O/H ratio (water abundance) and constrain core mass to decide among alternative theories of origin. Interior: Understand Jupiter's interior structure and dynamical properties by mapping its gravitational and magnetic fields Atmosphere: Map variations in atmospheric composition, temperature, cloud opacity and dynamics to depths greater than 100 bars at all latitudes. Magnetosphere: Characterize and explore the three-dimensional structure of Jupiter's polar magnetosphere and auroras.

  12. Reproductive biology of the band-tailed pigeon in Colorado and New Mexico

    USGS Publications Warehouse

    Gutierrez, R.J.; Braun, C.E.; Zapatka, T.P.

    1975-01-01

    Band-tailed pigeons (Columba fasciata) occur in two major populations in western North America, a coastal population (C. f. monilis) and an interior population (C. f. fasciata) (A.O.U. 1957). The interior population inhabits portions of Colorado, New Mexico, Arizona, Utah, Texas, and the highlands of Mexico. This pigeon is one of several species of birds in western North America that show unseasonal and variable nesting periods (see Ligon 1971). Active nests have been found in some portion of the species' range in every month of the year (Swarth 1900, Thayer 1909, Stephens 1913, Lamb 1926, Abbott 1927, Vorhies 1928, Neff 1947, MacGregor and Smith 1955). Although several studies of the breeding biology of the Band-tailed Pigeon have been made on the Pacific coast population (Glover 1953, MacGregor and Smith 1955, Houston 1963, March and Sadleir 1970, Zeigler 1971) few studies have been done of the interior population (Fitzhugh 1970). The breeding cycle of the interior population is poorly understood, although many observations of individual nests have been reported (Neff 1947, Fitzhugh 1970). The purpose of this study was to document the gonadal cycles of free-living Band-tailed Pigeons in Colorado and New Mexico and to study the species' photoperiod responses. From this information we have attempted to explain the normal breeding cycle of the pigeon and to explain its occasional unseasonal breeding.

  13. Constraining Mercury's interior structure with geodesy data and its present thermal state

    NASA Astrophysics Data System (ADS)

    Rivoldini, Attilio; Van Hoolst, Tim; Noack, Lena

    2015-04-01

    Recent measurements of Mercury's spin state and gravitational field supplemented by the assumption that the planet's core is made of iron and sulfur give strong constraints on its interior structure. In particular, they allow a precise determination of Mercury's core size and average mantle density. Present geodesy data do, however, almost not constrain the size of the inner core. Interior structure models with a fully molten liquid core as well as models with an inner core almost as large as the core agree with the observations. Additionally, the observed internally generated magnetic field of Mercury does not preclude the absence of an inner core, since remelting of iron snow inside the core could produce a sufficient buoyancy flux to drive magnetic field generation by compositional convection. Although sulfur is ubiquitously invoked as being the principal candidate light element in terrestrial planet's cores its abundance in the core depends on the redox conditions during planetary formation. Remote sensing data of Mercury's surface by MESSENGER indicate that Mercury formed under reducing conditions. As a consequence, substantial amounts of other light elements like for example silicon and carbon could be present together with sulfur inside Mercury's core. Compared to sulfur, which does almost not partition into solid iron at Mercury's core conditions, silicon partitions almost equally well between solid and liquid iron whereas a few percent of carbon can partition into solid iron. Therefore, compared to a pure iron-sulfur core, if silicon and carbon are present in the core the density jump at the inner-core outer-core boundary could be smaller and induce a large enough change in the inner-core flattening to alter Mercury's libration amplitude. Moreover, the presence of carbon together with sulfur further reduces the core solidus temperature, potentially delaying the onset of inner core formation. Finally, if both silicon and sulfur are present in sufficient quantities a thin layer much enriched in sulfur and depleted in silicon could form at the top of the core as a consequence of a large immiscibility region in liquid Fe-S-Si at Mercury's core conditions. The present radius of an inner core depends mainly on Mercury's thermal state and concentration of light elements inside the core. Because of the secular cooling of the planet, at a time in Mercury's evolution the temperature inside the core drops below the core liquidus temperature somewhere in the core, which can lead to the formation of an inner core and to the global contraction of the planet. The amount of contraction depends mainly on the temperature decrease, on the thermal expansion of the materials inside the planet, on the volume of crystallized iron-rich core liquid, and on the volume of crystallized crust. In this study we use geodesy data (88 day libration amplitude, polar moment of inertia, and tidal Love number), the recent estimate about the radial contraction of Mercury, and thermo-chemical evolution calculations taking into account the formation of the crust, a growing inner core, and modeling the formation of iron-rich snow in the core in order to improve our knowledge about Mercury's inner core radius and thermal state. Since data from remote sensing of Mercury's surface indicate that Mercury formed under reducing conditions we consider models that have sulfur, silicon, and carbon as light elements inside their core.

  14. Martian interior structure models with different crustal density

    NASA Astrophysics Data System (ADS)

    Gudkova, T. V.; Zharkov, V. N.

    2007-08-01

    The information necessary to construct a model of Mars (observation data, a choice of a chemical model, a cosmogonic aspect of the problem) is discussed. We consider an interior structure model which comprises four submodels - a model of the outer porous layer, a model of the crust, a model of the mantle and a model of the core. The first 10-11 km layer is considered as an averaged transition from regolith to consolidated rock. The mineral composition of the crustal basaltic rock varies with depth because of the gabbro-eclogite phase transition. Mineralogical and seismic models of the Martian crust were constructed by numerical thermodynamic simulation by Babeiko and Zharkov (2000). For the obtained from this simulation densities at the crust-mantle boundary (about 3.3-3.4 g/cm3) a density contrast between the crust and the mantle is low enough. However, the joint interpretation of gravity and topography data assumes that there is a noticeable density jump at the crust-mantle boundary. As discussed by many authors a plausible range of bulk crustal densities is from 2.7 to 3.1 g/ cm3. It can be interpreted as either the composition of rocks at the surface of Mars is somewhat different than those of the Martian basaltic meteorites or a certain amount of crustal porosity might be expected if water (or some other substances) is present in the subsurface. Assuming a range of crustal densities (2.7-3.2 g/cm3) and the average thickness of the martian crust of 50 and 100 km we have recalculated a set of interior structure models of Mars to determine this effect on the other model parameters. The models are stronly constrained by new values of Love number k2 and the mean moment of inertia have been derived by Konopliv et al. (2006). The inferred radius of Martian core (from the Love number k2) is between 1700 and 1800 km. Keeping in mind that the estimated value of the correction introduced to the Love number k2 due to the inelasticity of the interior can be both somewhat higher (~ 0.005) or slightly lower (~ 0.003) we have the inferred model radius of Martian core between 1650 and 1830 km. As the radius of the core is increasing two tendencies are seen: the density of the core is decreasing and the Fe/Si weight ratio is approaching to its chondritic value 1.7. From cosmochemical point of view, it is difficult to assume that the core contains more than 20 wt % of sulfur. The radius of such core is about 1600 km. Therefore, if the core of Mars turns out to be larger, it should contain some light admixture elements.

  15. Land-surface evolution at the continental time-scale: An example from interior Western Australia

    NASA Astrophysics Data System (ADS)

    Mabbutt, J. A.

    1988-12-01

    The interior plateau of Western Australia in the Wiluna—Meekatharra area is in part an exhumed pre-Permian surface of low relief and to that extent of Gondwana age. A lateritic duricrust on interfluvial remnants of an Old Plateau surface is probably the outcome of several cycles of weathering and stripping, rather than of a single geomorphic episode. Landforms above the Old Plateau have maintained their relief during this circumdenudation and there is no regional evidence of their isolation by major escarpment retreat. A New Plateau surface has extended by stripping of saprolite and is an etchplain, as also is the Old Plateau under the genesis postulated. The New Plateau cycle was initiated by general drainage rejuvenation whilst lateritic weathering still continued, but its extension was halted through increasing climatic aridity, probably during the Miocene.

  16. Amphibian, reptilian, and avian remains from the Fox Hills Formation (Maastrichtian): Shoreline and estuarine deposits of the Pierre Sea in south-central North Dakota

    USGS Publications Warehouse

    Hoganson, J.W.; Erickson, J.M.; Holland, F.D.

    2007-01-01

    Although vertebrate fossils, except for fish, are not common in the Maastrichtian Fox Hills Formation, amphibian, reptilian, and avian remains have been recovered at several localities in south-central North Dakota from shoreline facies of the retreating Pierre-Fox Hills seaway. This mixed fauna of aquatic, terrestrial, and marine taxa provides insight into the composition of coastal communities and habitats at the interface between the Hell Creek delta and the Western Interior Seaway. The delta-platform aquatic paleocommunity is represented by the efficient swimming salamanders Opistho- trition kayi and Lisserpeton bairdi, the carnivorous soft-shelled turtle "Aspideretes" sensu lato, the underwater piscivorous predator Champsosaurus laramiensis, and the large, predatory crocodile IBorealosuchus. Terrestrial areas were inhabited by the tortoise-like Basilemys and the predatory dinosaurs Tyrannosaurus and cf. Saurornit- holestes. Birds occupied niches in the warm-temperate to subtropical, forested delta platform and shoreline areas. These nonmarine taxa in the Fox Hills Formation indicate that the geographic range of these animals extended to shoreline areas of the Western Interior Seaway. The toxochelyid turtle Lophochelys and the ambush predators Mosasaurus dekayi and IPlioplatecarpus resided in the shallow marine and estuarine habitats. These taxa and marine fish taxa reported earlier indicate that normal marine conditions in south- central North Dakota persisted into the latest Late Cretaceous in comparison with coeval Hell Creek Formation sites more distal from the Western Interior Seaway. ?? 2007 The Geological Society of America. All rights reserved.

  17. Source identification of western Oregon Douglas-Fir wood cores using mass spectrometry and random forest Classification

    Treesearch

    Kristen Finch; Edgard Espinoza; F. Andrew Jones; Richard Cronn

    2017-01-01

    Premise of the study: We investigated whether wood metabolite profiles from direct analysis in real time (time-of-flight) mass spectrometry (DART-TOFMS) could be used to determine the geographic origin of Douglas-fir wood cores originating from two regions in western Oregon, USA. Methods: Three annual ring mass...

  18. Europa's differentiated internal structure: inferences from two Galileo encounters.

    PubMed

    Anderson, J D; Lau, E L; Sjogren, W L; Schubert, G; Moore, W B

    1997-05-23

    Doppler data generated with the Galileo spacecraft's radio carrier wave during two Europa encounters on 19 December 1996 (E4) and 20 February 1997 (E6) were used to measure Europa's external gravitational field. The measurements indicate that Europa has a predominantly water ice-liquid outer shell about 100 to 200 kilometers thick and a deep interior with a density in excess of about 4000 kilograms per cubic meter. The deep interior could be a mixture of metal and rock or it could consist of a metal core with a radius about 40 percent of Europa's radius surrounded by a rock mantle with a density of 3000 to 3500 kilograms per cubic meter. The metallic core is favored if Europa has a magnetic field.

  19. Science You Can Use Bulletin: Return of the king: Western white pine conservation and restoration in a changing climate

    Treesearch

    Sarah Hines; Ned Klopfenstein; Bryce Richardson; Marcus Warwell; Mee-Sook Kim

    2013-01-01

    Western white pine (Pinus monticola) is a species that used to dominate the forests of the Interior Northwest prior to the expansion of the Northern Pacific Railroad in the late 19th century. Its foundational role contributed to a landscape that was resilient, fire-adapted, and provided abundant suitable habitat for terrestrial and aquatic species. However, substantial...

  20. Red giants seismology

    NASA Astrophysics Data System (ADS)

    Mosser, B.; Samadi, R.; Belkacem, K.

    2013-11-01

    The space-borne missions CoRoT and Kepler are indiscreet. With their asteroseismic programs, they tell us what is hidden deep inside the stars. Waves excited just below the stellar surface travel throughout the stellar interior and unveil many secrets: how old is the star, how big, how massive, how fast (or slow) its core is dancing. This paper intends to paparazze the red giants according to the seismic pictures we have from their interiors.

  1. Lewis and Clark Elementary School Riverview Gardens School District, St. Louis, Missouri. Profile of a Significant School.

    ERIC Educational Resources Information Center

    Gilliland, John W.

    Development of a design for a new elementary school facility is traced through evaluation of various innovative facilities. Significant features include--(1) the spiral plan form, (2) centralized core levels including teacher work center, "perception" core, and interior stream aquariam, (3) the learning laboratory classroom suites, (4) a unique…

  2. Origin of limestone-marlstone cycles: Astronomic forcing of organic-rich sedimentary rocks from the Cenomanian to early Coniacian of the Cretaceous Western Interior Seaway, USA

    NASA Astrophysics Data System (ADS)

    Eldrett, James S.; Ma, Chao; Bergman, Steven C.; Ozkan, Aysen; Minisini, Daniel; Lutz, Brendan; Jackett, Sarah-Jane; Macaulay, Calum; Kelly, Amy E.

    2015-08-01

    We present an integrated multidisciplinary study of limestone-marlstone couplets from a continuously cored section including parts of the upper Buda Limestone, the entire Eagle Ford Group (Boquillas Formation) and lower Austin Chalk from the Shell Iona-1 research borehole (Texas, USA), which provides a >8 million year (myr) distal, clastic sediment-starved, intrashelf basin record of the early Cenomanian to the earliest Coniacian Stages. Results show that despite variable yet minimal diagenetic overprints, several unambiguous primary environmental signals are preserved and support greater water-mass ventilation and current activity promoting increased silica/carbonate productivity during the deposition of limestone beds compared to deposition of marlstone beds which reflect greater organic matter productivity and preservation. Furthermore, our astronomical analyses demonstrate that the limestone-marlstone couplets in the Iona-1 core reflect climatic forcing driven by solar insolation resulting from integrated Milankovitch periodicities. In particular, we propose that obliquity and precession forcing on the latitudinal distribution of solar insolation may have been responsible for the observed lithological and environmental variations through the Cenomanian, Turonian and Coniacian in this mid-latitude epicontinental sea setting. Our data also suggests that rhythmic lithological alternations deposited in Greenhouse periods, in general, may simply reflect climate-driven cycles related to Earth-Sun dynamics without the need to invoke significant sea-level variations.

  3. Models of a partially hydrated Titan interior with a clathrate crust

    NASA Astrophysics Data System (ADS)

    Lunine, J. I.; Castillo-Rogez, J. C.; Choukroun, M.; Sotin, C.

    2012-04-01

    We present a model of the interior evolution of Titan over time, assuming the silicate core was hydrated early in Titan’s history and is dehydrating over time. The original model presented in Castillo-Rogez and Lunine (2010) was motivated by a Cassini-derived moment of inertia (Iess et al., 2010) for Titan too large to be accommodated by classical fully differentiated models in which an anhydrous silicate core was overlain by a water ice (with possible perched ocean) mantle. Our model consists of a silicate core still in the process of dehydrating today, a situation made possible by the leaching of radiogenic potassium from the silicates into the perched liquid water ocean. The most recent version of our model accounts for the likely presence of large amounts of methane in the upper crust invoked to explain methane’s persistence at present and through geologic time (Tobie et al. 2006). The methane-rich crust turns out to have essentially no bearing on the temperature of the silicate core and hence the timing of dehydration, but it profoundly affects the thickness of the high-pressure ice layer beneath the ocean. Indeed, the insulating effect of the methane clathrate crust could have delayed the formation of the high-pressure layer, resulting in the interaction of liquid water with the silicate core for extended periods of time. Although a high-pressure ice layer is likely in place today, it is thin enough that plumes of hot water from the dehydrating core probably breach that layer. The implications of such a deep hydrothermal system for the later stages of the evolution of Titan’s interior and surface will be discussed. Part of this work has been performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA. Government sponsorship acknowledged. References: Castillo-Rogez, J., Lunine, J.: “Evolution of Titan’s rocky core constrained by Cassini observations”. GRL, Vol. 37, L20205, 2010. Iess, L., et al.: “Gravity field, shape, and moment of inertia of Titan”. Science, Vol. 327, 1367-1369. Tobie, G., et al.: “Episodic outgassing as the origin of atmospheric methane on Titan”. Nature 440: 61-64, 2006.

  4. The Density Jump at the Inner Core Boundary in the Eastern and Western Hemispheres

    NASA Astrophysics Data System (ADS)

    Krasnoshchekov, D. N.; Ovtchinnikov, V. M.

    2018-02-01

    The results of analysis of more than 1300 new PKiKP/PcP amplitude ratios measured in Southeast Asia and South America at the epicentral distances of 3.2°-35.2° are presented. The density jump in the Eastern Hemisphere of the Earth's inner core (IC) is 0.3 g/cm3, and it is 0.9 g/cm3 in the Western one. Taking the large discrepancy in the obtained estimates into consideration, maintenance of such large lateral variations in the mosaic properties of the IC reflecting surface requires considerable variations in the thermodynamic parameters (mostly temperature) of the inner-outer core transition. However, if the observed asymmetry in the density jump distribution is of a global character, the data presented support the translation model of the IC dynamics. This model implies IC crystallization in the Western Hemisphere and melting in the Eastern one, not vice versa, as suggested by another geodynamic model based on thermochemical convection in the outer core and the thermal balance of the core-mantle system.

  5. Modes of mantle convection and the removal of heat from the earth's interior

    NASA Technical Reports Server (NTRS)

    Spohn, T.; Schubert, G.

    1982-01-01

    Thermal histories for two-layer and whole-mantle convection models are calculated and presented, based on a parameterization of convective heat transport. The model is composed of two concentric spherical shells surrounding a spherical core. The models were constrained to yield the observed present-day surface heat flow and mantle viscosity, in order to determine parameters. These parameters were varied to determine their effects on the results. Studies show that whole-mantle convection removes three times more primordial heat from the earth interior and six times more from the core than does two-layer convection (in 4.5 billion years). Mantle volumetric heat generation rates for both models are comparable to that of a potassium-depleted chondrite, and thus surface heat-flux balance does not require potassium in the core. Whole and two-layer mantle convection differences are primarily due to lower mantle thermal insulation and the lower heat removal efficiency of the upper mantle as compared with that of the whole mantle.

  6. Core filaments of the nuclear matrix

    PubMed Central

    1990-01-01

    The nuclear matrix is concealed by a much larger mass of chromatin, which can be removed selectively by digesting nuclei with DNase I followed by elution of chromatin with 0.25 M ammonium sulfate. This mild procedure removes chromatin almost completely and preserves nuclear matrix morphology. The complete nuclear matrix consists of a nuclear lamina with an interior matrix composed of thick, polymorphic fibers and large masses that resemble remnant nucleoli. Further extraction of the nuclear matrices of HeLa or MCF-7 cells with 2 M sodium chloride uncovered a network of core filaments. A few dark masses remained enmeshed in the filament network and may be remnants of the nuclear matrix thick fibers and nucleoli. The highly branched core filaments had diameters of 9 and 13 nm measured relative to the intermediate filaments. They may serve as the core structure around which the matrix is constructed. The core filaments retained 70% of nuclear RNA. This RNA consisted both of ribosomal RNA precursors and of very high molecular weight hnRNA with a modal size of 20 kb. Treatment with RNase A removed the core filaments. When 2 M sodium chloride was used directly to remove chromatin after DNase I digestion without a preceding 0.25 M ammonium sulfate extraction, the core filaments were not revealed. Instead, the nuclear interior was filled with amorphous masses that may cover the filaments. This reflected a requirement for a stepwise increase in ionic strength because gradual addition of sodium chloride to a final concentration of 2 M without an 0.25 M ammonium sulfate extraction uncovered core filaments. PMID:2307700

  7. Reconstructing a mid-Cretaceous landscape from paleosols in western Canada

    USGS Publications Warehouse

    Ufnar, David F.; Gonzalez, Luis A.; Ludvigson, Greg A.; Brenner, Richard L.; Witzke, B.J.; Leckie, D.

    2005-01-01

    The Albian Stage of the mid-Cretaceous was a time of equable climate conditions with high sea levels and broad shallow epeiric seas that may have had a moderating affect on continental climates. A Late Albian landscape surface that developed during a regression and subsequent sea-level rise in the Western Canada Foreland Basin is reconstructed on the basis of correlation of paleosols penetrated by cores through the Paddy Member of the Peace River Formation. Reconstruction of this landscape refines chronostratigraphic relationships and will benefit future paleoclimatological studies milizing continental sphaerosiderite proxy records. The paleosols developed in estuarine sandstones and mudstones, and they exhibit evidence of a polygenetic history. Upon initial exposure and pedogenesis, the Paddy Member developed deeply weathered, well-drained cumulative soil profiles. Later stages of pedogenesis were characterized by hydromorphic soil conditions. The stages of soil development interpreted for the Paddy Member correlate with inferred stages of pedogenic development in time-equivalent formations located both basinward and downslope (upper Viking Formation), and landward and upslope (Boulder Creek Formation). On the basis of the genetic similarity among paleosols in these three correlative formations, the paleosols are interpreted as having formed along a single, continuous landscape surface. Results of this study indicate that the catena concept of pedogenesis along sloping landscapes is applicable to ancient successions. Sphaerosiderites in the Paddy Mem ber paleosols are used to provide proxy values for meteoric ??18O values at 52?? N paleolatitude in the Cretaceous Western Interior Basin. The meteoric ??18O values are used to refine existing interpretations about the mid-Cretaceous paleolatitudinal gradient in meteoric ?? 18O values, and the mid-Cretaceous hydrologic cycle. Copyright ?? 2005, SEPM (Society for Sedimentary Geology).

  8. Bioclimatic modeling predicts potential distribution of Armillaria solidipes and Pseudotsuga menziesii (Douglas-fir) under contemporary and changing climates in the interior western U.S.A

    Treesearch

    John Hanna; M. V. Warwell; H. Maffei; M. L. Fairweather; J. T. Blodgett; P. J. Zambino; J. Worrall; K. S. Burns; J. J. Jacobs; S. M. Ashiglar; J. E. Lundquist; M. -S. Kim; Amy Ross-Davis; C. Hoffman; R. Mathiasen; R. Hofstetter; John Shaw; E. W. I. Pitman; E. V. Nelson; Geral I. McDonald; M. R. Cleary; S. Brar; B. Richardson; Ned Klopfenstein

    2016-01-01

    Pseudotsuga menziesii (Douglas-fir) is a dominant component of forest stands in much of western North America. It is an important tree to the timber industry, yielding more timber than any other species in North America. It is also extremely important for wildlife as habitat and food. Many small birds and mammals feed on its seeds . Armillaria solidipes [...

  9. Core losses of an inverter-fed permanent magnet synchronous motor with an amorphous stator core under no-load

    NASA Astrophysics Data System (ADS)

    Denis, Nicolas; Kato, Yoshiyuki; Ieki, Masaharu; Fujisaki, Keisuke

    2016-05-01

    In this paper, an interior permanent magnet synchronous motor (IPMSM) with a stator core made of amorphous magnetic material (AMM) is presented. The IPMSM is driven by a voltage source three-phase inverter with classical pulse width modulation (PWM) control. The core losses under no-load condition are measured by experiment and compared to an equivalent IPMSM with a stator core made of NO steel. Under these conditions, the core losses are influenced by the stator, rotor and magnet shapes but also by the PWM carrier signal that implies a high frequency harmonic in the magnetic flux density. It is demonstrated that the AMM can reduce the core losses by about 56 %.

  10. Geographic variation in migration chronology and winter distribution of midcontinent greater white-fronted geese

    USGS Publications Warehouse

    Ely, Craig R.; Nieman, Daniel J.; Alisauskas, Ray T.; Schmutz, Joel A.; Hines, James E.

    2013-01-01

    We evaluated spatial and temporal differences in migratory behavior among different breeding groups of midcontinent greater white-fronted geese (Anser albifrons) using band-recovery data and observations of neck collared geese during migration and winter. Birds from different breeding areas were initially delineated by geographic distance into 6 banding reference areas (BRAs): 1) interior Alaska, 2) North Slope of Alaska, 3) western Northwest Territories (NWT), 4) western Nunavut, 5) central Nunavut, and 6) eastern Nunavut. The banding groups also differed by breeding habitat, with geese from interior Alaska nesting in the boreal forest (taiga), and all other groups breeding in tundra habitats. Geese from interior Alaska migrated earlier during autumn, and were more likely to winter farther south (in Mexico) than geese from other breeding areas. Geese banded in central and eastern Nunavut (Queen Maud Gulf and Inglis River) wintered farther east (in Louisiana) than geese from other breeding areas. Small-scale (within-state) geographic segregation of wintering flocks was evidenced by the recent (post-1990) nearly exclusive use of a new wintering area in north central Texas by geese from interior Alaska. Segregation among BRAs was also apparent in Mexico, where taiga geese were found predominantly in the central Highlands (states of Zacatecas and Durango), whereas tundra geese mostly used states along the Gulf Coast (primarily Tamaulipas). Interior Alaska birds initiated spring migration earlier than geese from other areas, and were more likely than others to stop in the Rainwater Basin of Nebraska, a region where cholera outbreaks periodically kill thousands of geese. Geese from interior Alaska were the first to arrive at spring staging areas in prairie Canada where BRAs exhibited spatial delineation (a longitudinal cline) in relation to breeding areas. Our results show significant geographic and temporal variation among taiga and tundra breeding cohorts during autumn, winter, and spring. Temporal and spatial differences in migratory behavior may allow management practices that accommodate potential demographic differences between taiga and tundra populations.

  11. Using seismic reflection data to reveal high-resolution structure and pathway of the upper Western Boundary Undercurrent core at Eirik Drift

    NASA Astrophysics Data System (ADS)

    Müller-Michaelis, Antje; Uenzelmann-Neben, Gabriele

    2015-12-01

    The method of seismic oceanography was applied to identify fine structure and pathways of the Western Boundary Undercurrent (WBUC) at Eirik Drift, 200 km south of Greenland. Three high-velocity cores of the WBUC were distinguished: a deep core in depths >2600 m which carries Denmark Strait Overflow Water, an upper core in depths between ~1900 and 3000 m transporting Iceland-Scotland Overflow Water, and a split-off of this upper core, which crosses the main crest of Eirik Drift at depths between ~1900 and 2400 m. For the upper WBUC core a detailed analysis of the structure was conducted. The WBUC core has as a domed structure, which changes in style, width and height above seafloor along the lines of the changing topography. We proved not only the influence of the topography on pathway and structure of the WBUC core but also that this information cannot be gained by measuring the overflow waters with discrete CTD stations.

  12. Robot arm apparatus

    DOEpatents

    Nachbar, Henry D.

    1992-12-01

    A robot arm apparatus is provided for inspecting and/or maintaining an interior of a steam generator which has an outside wall and a port for accessing the interior of the steam generator. The robot arm apparatus includes a flexible movable conduit for conveying inspection and/or maintenance apparatus from outside the steam generator to the interior of the steam generator. The flexible conduit has a terminal working end which is translated into and around the interior of the steam generator. Three motors located outside the steam generator are employed for moving the terminal working end inside the steam generator in "x", "y", and "z" directions, respectively. Commonly conducted inspection and maintenance operations include visual inspection for damaged areas, water jet lancing for cleaning sludge deposits, core boring for obtaining sludge deposits, and scrubbing of internal parts.

  13. Robot arm apparatus

    DOEpatents

    Nachbar, Henry D.

    1992-01-01

    A robot arm apparatus is provided for inspecting and/or maintaining an interior of a steam generator which has an outside wall and a port for accessing the interior of the steam generator. The robot arm apparatus includes a flexible movable conduit for conveying inspection and/or maintenance apparatus from outside the steam generator to the interior of the steam generator. The flexible conduit has a terminal working end which is translated into and around the interior of the steam generator. Three motors located outside the steam generator are employed for moving the terminal working end inside the steam generator in "x", "y", and "z" directions, respectively. Commonly conducted inspection and maintenance operations include visual inspection for damaged areas, water jet lancing for cleaning sludge deposits, core boring for obtaining sludge deposits, and scrubbing of internal parts.

  14. Distribution and abundance of nesting ospreys in the United States

    USGS Publications Warehouse

    Henny, C.J.

    1983-01-01

    Nesting Ospreys (Pandion haliaetus) in the contiguous United States now number about 8,000 pairs. Five regional populations exist (in order of abundance): Atlantic Coast, Florida and Gulf Coast, Pacific Northwest, Western Interior, and Great Lakes. Pesticides severely impacted the populations in the northern portion of the Atlantic Coast (Boston to Cape May) and the Great Lakes, but both are now recovering. During recent years in the west, especially in the Western Interior, reservoirs have been responsible for a range expansion and, perhaps, a population increase. However, a strong fidelity to ancestral breeding areas (short dispersal distance) has slowed the range expansion. Unique introductions to distant reservoirs (from breeding populations) are now being made and followed with intense interest. Ospreys adapted to man, his structures, and many of his habitat changes, but proved sensitive to his chemical pollutants. These characteristics make the Osprey an excellent environmental indicator species.

  15. A post-Galileo view of Io's interior

    USGS Publications Warehouse

    Keszthelyi, L.; Jaeger, W.L.; Turtle, E.P.; Milazzo, M.; Radebaugh, J.

    2004-01-01

    We present a self-consistent model for the interior of Io, taking the recent Galileo data into account. In this model, Io has a completely molten core, substantially molten mantle, and a very cold lithosphere. Heat from magmatic activity can mobilize volatile compounds such as SO2 in the lithosphere, and the movement of such cryogenic fluids may be important in the formation of surface features including sapping scarps and paterae. ?? Published by Elsevier Inc.

  16. Identifying core habitat and connectivity for focal species in the interior cedar-hemlock forest of North America to complete a conservation area design

    Treesearch

    Lance Craighead; Baden Cross

    2007-01-01

    To identify the remaining areas of the Interior Cedar- Hemlock Forest of North America and prioritize them for conservation planning, the Craighead Environmental Research Institute has developed a 2-scale method for mapping critical habitat utilizing 1) a broad-scale model to identify important regional locations as the basis for a Conservation Area Design (CAD), and 2...

  17. Insights into Mercury's interior structure from geodesy measurements and global contraction

    NASA Astrophysics Data System (ADS)

    Rivoldini, A.; Van Hoolst, T.

    2014-04-01

    The measurements of the gravitational field of Mercury by MESSENGER [6] and improved measurements of the spin state of Mercury [3] provide important insights on its interior structure. In particular, these data give strong constraints on the radius and density of Mercury's core [5, 2]. However, present geodesy data do not provide strong constraints on the radius of the inner core. The data allow for models with a fully molten liquid core to models which have an inner core radius that is smaller than about 1760km [5], if it is assumed that sulfur is the only light element in the core. Models without an inner core are, however, at odds with the observed internally generated magnetic field of Mercury since Mercury's dynamo cannot operate by secular cooling alone at present. The present radius of the inner core depends mainly on Mercury's thermal state and light elements inside the core. Because of the secular cooling of the planet,the temperature inside the core drops below the liquidus temperature of the core material somewhere in the core and leads to the formation of an inner core and to the global contraction of the planet. The amount of contraction depends on the temperature decrease, on the thermal expansion of the materials inside the planet, and on the volume of crystallized liquid core alloy. In this study we use geodesy data, the recent estimate about the radial contraction of Mercury [1], and thermo-chemical evolution calculations in order to improve our knowledge about Mercury's inner core radius and thermal state. Since data from remote sensing of Mercury's surface [4] indicate that Mercury formed under reducing conditions we consider models that have sulfur and silicon as light elements inside their core. Unlike sulfur, which does almost not partition into solid iron under Mercury's core pressure and temperature conditions, silicon partitions virtually equally between solid and liquid iron. As a consequence, the density difference between the liquid and the crystallized material is smaller than for sulfur as only light element inside the core and therefore, for a given inner core radius the contraction of the planet is likely smaller.

  18. FUEL ELEMENT CONSTRUCTION

    DOEpatents

    Zumwalt, L.R.

    1961-08-01

    Fuel elements having a solid core of fissionable material encased in a cladding material are described. A conversion material is provided within the cladding to react with the fission products to form stable, relatively non- volatile compounds thereby minimizing the migration of the fission products into the coolant. The conversion material is preferably a metallic fluoride, such as lead difluoride, and may be in the form of a coating on the fuel core or interior of the cladding, or dispersed within the fuel core. (AEC)

  19. Adjustment of Jacobs' formulation to the case of Mercury

    NASA Astrophysics Data System (ADS)

    Chiappini, M.; de Santis, A.

    1991-04-01

    Magnetic investigations play an important role in studies on the constitution of planetary interiors. One of these techniques (the so-called Jacobs' formulation), appropriately modified, has been applied to the case of Mercury. According to the results found, the planet, supposed to be divided internally as the earth (crust-mantle-core), would have a core/planet volume ratio of 28 percent, much greater than the earth's core percentage (16 percent). This result is in agreement with previous work which used other independent methods.

  20. Thermal History of Planetary Objects: From Asteroids to super-Earths, from plate-tectonics to life (Runcorn-Florensky Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Spohn, Tilman

    2013-04-01

    Convection in the interiors of planetesimals (asteroids), planets, and satellites is driving the thermal and chemical evolution of these bodies including the generation of possible magnetic fields. The wide size range induces a wide of range of time scales from hundreds of thousands of years for small planetesimals to a few tens of Gigayears for massive super-Earths. Evolution calculations are often based on energy (and entropy) balances parameterizing the transport properties of the interior in suitable ways. These thereby allow incorporating (in parameterized forms) interesting physical processes that depend in one way or another on the transport properties of the interior. The interior will usually be chemically layered in mantles and cores and include ice layers if icy satellites are considered. In addition to magnetic field generation calculated via energy balances of the core and using semi-empirical dynamo strength relations, processes that can be considered include sintering and compaction for small bodies and mantle (or ice) melting, differentiation and even continental growth for full-scaled terrestrial planets. The rheology of the interior is considered temperature and pressure dependent and the concentration of volatiles can be important. For super-Earths, probably the most critical consideration is how the mantle rheology would vary with pressure and thus with depth. It is possible that the increasing pressure will frustrate deep mantle convection thereby reducing the vigor of mantle convection. Possibly, the generation of a magnetic field in a putative iron-rich core will be impossible, if super-Earths at all have earth-like cores. On a much smaller scale, the decay of short-lived radioactives suffices to heat and melt planetesimals, the melting being helped by the low thermal conductivity of the initially porous body. This allows planets to form from pre-differentiated planetesimals thus helping to differentiate and form cores rapidly. On active planets - like the Earth - the volatile budget matters for the interior evolution. With plate tectonics, large-scale volatile cycles are invoked. On the Earth, even the biosphere is speculated to interact with the interior. It has been argued (e.g., Rosing et al. 2006; Sleep et al, 2012) that the formation of continents could be a consequence of bioactivity harvesting solar energy through photosynthesis to help build the continents and that the mantle should carry a chemical biosignature. A model is presented that includes mantle convection, mantle water vapor degassing at mid-oceanic ridges and regassing through subduction zones, continental crust formation and erosion and water storage and transport in a porous oceanic crust that includes hydrous mineral phases. The biosphere enters the model through its effect on continental erosion and through a reduction of the activation barrier to metamorphic reactions (e.g., Kim et al., 2004) in sediment layers. An abiotic world is found to have a much drier mantle than the present Earth but may have a similar surface coverage by continents. The reduced rate of continental crust production on the abiotic world would be balanced by a reduced rate of continent erosion. Through the effect of water on the mantle rheology, the biotic world would tend to be tectonically more active and have a more rapid long-term carbon-silicate cycle. J. Kim, H. Dong, J. Seabaugh, S. W. Newell, D. D. Eberl, Science 303, 830-832, 2004 N. H. Sleep, D. K. Bird, E. Pope, Annu. Rev. Earth Planet. Sci. 40, 277-300, 2012 M. T. Rosing, D. K. Bird, N. H. Sleep, W. Glassley, F. Albarede, Paleo3 232, 90-113, 2006

  1. Observed and modeled pathways of the Iceland Scotland Overflow Water in the eastern North Atlantic

    NASA Astrophysics Data System (ADS)

    Zou, Sijia; Lozier, Susan; Zenk, Walter; Bower, Amy; Johns, William

    2017-12-01

    The spreading of Iceland Scotland Overflow Water (ISOW) in the eastern North Atlantic has largely been studied in an Eulerian frame using numerical models or with observations limited to a few locations. No study to date has provided a comprehensive description of the ISOW spreading pathways from both Eulerian and Lagrangian perspectives. In this paper, we use a combination of previously unreported current meter data, hydrographic data, RAFOS float data, and a high resolution (1/12°) numerical ocean model to study the spreading pathways of ISOW from both of these perspectives. We identify three ISOW transport cores in the central Iceland Basin (∼59°N), with the major core along the eastern boundary of the Reykjanes Ridge (RR) and the other two in the basin interior. Based on trajectories of observed and/or numerical floats seeded along 59°N, we also describe the ISOW spreading pathways and quantify their relative importance. Within 10 years, 7-11% of ISOW from 59°N escapes into the Irminger Sea via gaps in the RR north of the Charlie Gibbs Fracture Zone (CGFZ); the water that moves through these gaps principally originates from the shallower ISOW layer along the RR eastern boundary. 10-13% travels further southward until the CGFZ, where it crosses westward into the western subpolar gyre. 18-21% of ISOW spreads southward along the eastern flank of the Mid-Atlantic Ridge into the Western European Basin (WEB). Most of the remaining water stays in the Iceland Basin over the 10-year period. A model-based investigation provides a first look at the temporal variability of these ISOW pathways. We find that the fraction of southward water exported into the WEB is anti-correlated with the export through the CGFZ, a result assumed to reflect these pathways' interactions with the North Atlantic Current in magnitude and/or position shift.

  2. Lid heater for glass melter

    DOEpatents

    Phillips, Terrance D.

    1993-01-01

    A glass melter having a lid electrode for heating the glass melt radiantly. The electrode comprises a series of INCONEL 690 tubes running above the melt across the melter interior and through the melter walls and having nickel cores inside the tubes beginning where the tubes leave the melter interior and nickel connectors to connect the tubes electrically in series. An applied voltage causes the tubes to generate heat of electrical resistance for melting frit injected onto the melt. The cores limit heat generated as the current passes through the walls of the melter. Nickel bus connection to the electrical power supply minimizes heat transfer away from the melter that would occur if standard copper or water-cooled copper connections were used between the supply and the INCONEL 690 heating tubes.

  3. Lid heater for glass melter

    DOEpatents

    Phillips, T.D.

    1993-12-14

    A glass melter having a lid electrode for heating the glass melt radiantly. The electrode comprises a series of INCONEL 690 tubes running above the melt across the melter interior and through the melter walls and having nickel cores inside the tubes beginning where the tubes leave the melter interior and nickel connectors to connect the tubes electrically in series. An applied voltage causes the tubes to generate heat of electrical resistance for melting frit injected onto the melt. The cores limit heat generated as the current passes through the walls of the melter. Nickel bus connection to the electrical power supply minimizes heat transfer away from the melter that would occur if standard copper or water-cooled copper connections were used between the supply and the INCONEL 690 heating tubes. 3 figures.

  4. Wood Anatomy and Insect Defoliator Systems: Is there an anatomical response to sustained feeding by the western spruce budworm (Choristoneura occidentalis) on Douglas-fir (Pseudotusga menziesii)?

    NASA Astrophysics Data System (ADS)

    Axelson, Jodi; Gärtner, Holger; Alfaro, René; Smith, Dan

    2013-04-01

    The western spruce budworm (Choristoneura occidentalis Freeman) is the most widespread and destructive defoliator of coniferous forests in western North America, and has a long-term coexistence with its primary host tree, Douglas-fir (Pseudotsuga menziesii Franco). Western spruce budworm (WSB) outbreaks usually last for several years, and cause reductions in annual growth, stem defects, and regeneration delays. In British Columbia, the WSB is the second most damaging insect after the mountain pine beetle, and sustained and/or severe defoliation can result in the mortality of host trees. Numerous studies have used tree rings to reconstruct WSB outbreaks across long temporal scales, to evaluate losses in stand productivity, and examine isotope ratios. Although some studies have looked at the impacts of artificial defoliation on balsam fir in eastern North America, there has been no prior research on how WSB outbreaks affect the anatomical structure of the stem as described by intra-annual wood density and potential cell size variations. The objective of this study was to anatomically examine the response of Douglas-fir to sustained WSB outbreaks in two regions of southern British Columbia. We hypothesize that the anatomical intra-annual characteristics of the tree rings, such as cell wall thickness, latewood cell size, and/or lumen area changes during sustained WSB outbreaks. To test this hypothesis we sampled four permanent sample plots in coastal and dry interior sites, which had annually resolved defoliation data collected over a 7-12 year period. At each site diameter-at-breast height (cm), height (m), and crown position were recorded and three increment cores were extracted from 25 trees. Increment cores were prepared to permit anatomical and x-ray density analyses. For each tree, a 15µm thick micro section was cut from the radial plane. Digital images of the micro sections were captured and processed. In each annual ring, features such as cell lumen area (µm2), cell wall thickness (µm), lumen diameter (µm), and total cell width (µm) were measured. Preliminary results indicate that earlywood parameters remain quite stable during WSB outbreak, while latewood parameters such as secondary cell wall thickness and cell length undergo step shifts at the beginning and end of outbreaks. These parameters, tree-level data, and annual defoliation data will further be tested to determine if changes in stem wood anatomy during WSB outbreaks were statistically significant.

  5. Recent climatic, cryospheric, and hydrological changes over the interior of western Canada: a synthesis and review

    NASA Astrophysics Data System (ADS)

    DeBeer, C. M.; Wheater, H. S.; Carey, S. K.; Chun, K. P.

    2015-08-01

    It is well-established that the Earth's climate system has warmed significantly over the past several decades, and in association there have been widespread changes in various other Earth system components. This has been especially prevalent in the cold regions of the northern mid to high-latitudes. Examples of these changes can be found within the western and northern interior of Canada, a region that exemplifies the scientific and societal issues faced in many other similar parts of the world, and where impacts have global-scale consequences. This region has been the geographic focus of a large amount of previous research on changing climatic, cryospheric, and hydrological Earth system components in recent decades, while current initiatives such as the Changing Cold Regions Network (CCRN) seek to further develop the understanding and diagnosis of this change and hence improve predictive capacity. This paper provides an integrated review of the observed changes in these Earth system components and a concise and up-to-date regional picture of some of the temporal trends over the interior of western Canada since the mid or late-20th century. The focus is on air temperature, precipitation, seasonal snow cover, mountain glaciers, permafrost, freshwater ice cover, and river discharge. Important long-term observational networks and datasets are described, and qualitative linkages among the changing components are highlighted. Systematic warming and significant changes to precipitation, snow and ice regimes are unambiguous. However, integrated effects on streamflow are complex. It is argued that further diagnosis is required before predictions of future change can be made with confidence.

  6. Formation and evolution of Lakshmi Planum, Venus: Assessment of models using observations from geological mapping

    NASA Astrophysics Data System (ADS)

    Ivanov, M. A.; Head, J. W.

    2008-12-01

    Detailed geological analysis of the Lakshmi Planum region of western Ishtar Terra results in the establishment of the sequence of major events during the formation and evolution of western Ishtar Terra, an important and somewhat unique area on Venus characterized by a raised volcanic plateau surrounded by distinctive folded mountain belts, such as Maxwell Montes. These mapping results and the stratigraphic and structural relationships provide a basis for addressing the complicated problem of Lakshmi Planum formation and for testing the suite of models previously proposed to explain this structure. We review and classify previous models of formation for western Ishtar Terra into "downwelling" models (generally involving convergence and underthrusting) and "upwelling" models (generally involving plume-like upwelling and divergence). The interpreted nature of units and the sequence of events derived from geological mapping are in contrast to the predictions of the divergent models. The major contradictions are as follows: (1) The very likely presence of an ancient (craton-like) tessera massif in the core of Lakshmi, which is inconsistent with the model of formation of Lakshmi due to rise and collapse of a mantle diapir; (2) The absence of rift zones in the interior of Lakshmi that are predicted by the divergent models; (3) The apparent migration of volcanic activity toward the center of Lakshmi, whereas divergent models predict the opposite trend; (4) The abrupt cessation of ridges of the mountain ranges at the edge of Lakshmi Planum and propagation of these ridges over hundreds of kilometers outside Lakshmi; the divergent models predict the opposite progression in the development of major contractional features. In contrast, convergent models of formation and evolution of Lakshmi Planum appear to be more consistent with the observations and explain this structure by collision and underthrusting/subduction of lower-lying plains with the elevated and rigid block of tessera. These models are capable of explaining formation of the major features of western Ishtar (for example, the mountain belts), the sequences of events, and principal volcanic and tectonic trends during the evolution of Lakshmi. To explain the pronounced north-south asymmetry of Lakshmi these models need to consider the likelihood that the major focal points of collision are at the north and north-west margins of the plateau. We note that pure downwelling models, however, face three important difficulties: (1) The possibly unrealistically long time span that appears to be required to produce the major features of Lakshmi; (2) The strong north-south asymmetry of the Planum; the pure downwelling models predict the formation of a more symmetrical structure; and (3) The absence of radial contractional structures (arches and ridges) in the interior of Lakshmi that would represent the predictions of the downwelling models.

  7. Global Cooling Drive Tectonic Scale Aridification of Asian Interior since Miocene

    NASA Astrophysics Data System (ADS)

    Jiang, F.; Zhu, X.

    2017-12-01

    Global cooling and the uplift of Tibetan Plateau are two potential mechanisms for tectonic scale aridification of Asian interior since Miocene. However, their relative importance is still controversial due to lack of continuous paleoclimate record. Here, using a 164 m long sediment core from Site U1438 in the Amami Sankaku Basin (ASB) in the NW Pacific, we show that the tectonic scale aridification of Asian interior is linked to global cooling rather than the uplift of the Tibetan Plateau. We analyzed the characteristics and variations of clastic mineral (e.g. quartz), clay minerals, radiogenic strontium (Sr) and neodymium (Nd) isotopes of the fine pelagic mud intervals from the sediment core. These new evidences indicate a continuous input of Asian dust from Asian interior to ASB since Miocene. We found that Asian dust in the ASB overall increased starting from ca.15.0 Myr (mid-Miocene), and ca. 3.5 Myr (Late Pliocene). The variations of Asian dust transport and accumulation closely responds to known times of enhanced Asian aridification and prevailing westerlies. The overall and gradual increase of Asian dust since mid-Miocene and Late Pliocene are in agreement with the formation and development of the polar ice caps, and are coupled with the gradual decrease of the global temperature recorded by the δ18O ratio of forams, but lag behind the tectonic uplift of the Tibetan Plateau. We argue that global cooling drove the aridification of the Asian interior and resulted in the increase of Asian dust deposition in the ASB.

  8. West-east lithostratigraphic cross section of Cretaceous rocks from central Utah to western Kansas

    USGS Publications Warehouse

    Anna, Lawrence O.

    2012-01-01

    A west-east lithostratigraphic cross section of the Cretaceous rocks from central Utah to western Kansas was prepared as part of the former Western Interior Cretaceous (WIK) project, which was part of the Global Sedimentary Geology Program started in 1989. This transect is similar to that published by Dyman and others (1994) as a summary paper of the WIK project but extends further east and is more detailed. Stratigraphic control was provided by 32 geophysical logs and measured sections tied to ammonite and Inoceramus faunal zones. A variable datum was used, including the base of the Castlegate Sandstone for the western part of the section, and the fossil ammonite zone Baculites obtusus for the middle and eastern section. Lower Cretaceous units and the Frontier Formation and Mowry Shale are shown as undifferentiated units. Cretaceous strata along the transect range in thickness from more than 7,000 ft in the structural foredeep of the western overthrust belt in central Utah, to about 11,000 ft near the Colorado-Utah border as a result of considerable thickening of the Mesaverde Group, to less than 3,500 ft in the eastern Denver Basin, Kansas resulting in a condensed section. The basal Mancos Shale rises stepwise across the transect becoming progressively younger to the west as the Western Interior Seaway transgressed westward. The section illustrates large scale stratigraphic relations for most of the area covered by the seaway, from central Utah, Colorado, to west-central Kansas. These strata are predominantly continental and shoreline deposits near the Sevier thrust belt in Utah, prograding and regressive shorelines to the east with associated flooding surfaces, downlapping mudstones, and transgressive parasequences (shoreface) that correlate to condensed zones across the seaway in central Colorado and eastern Denver Basin.

  9. Late albian kiowa-skull creek marine transgression, lower dakota formation, eastern margin of western interior seaway, U.S.A

    USGS Publications Warehouse

    Brenner, Richard L.; Ludvigson, Greg A.; Witzke, B.J.; Zawistoski, A.N.; Kvale, E.P.; Ravn, R.L.; Joeckel, R.M.

    2000-01-01

    An integrated geochemical-sedimentological project is studying the paleoclimatic and paleogeographic characteristics of the mid-Cretaceous greenhouse world of western North America. A critical part of this project, required to establish a temporal framework, is a stratigraphie study of depositional relationships between the AlbianCenomanian Dakota and the Upper Albian Kiowa formations of the eastern margin of the Western Interior Seaway (WIS). Palynostratigraphic and sedimentologic analyses provide criteria for the Dakota Formation to be divided into three sedimentary sequences bounded by unconformities (D0, D1, and D2) that are recognized from western Iowa to westernmost Kansas. The lowest of these sequences, defined by unconformities D0 and D1, is entirely Upper Albian, and includes the largely nonmarine basal Dakota (lower part of the Nishnabotna Member) strata in western Iowa and eastern Nebraska and the marine Kiowa Formation to the southwest in Kansas. The gravel-rich fluvial deposits of the basal part of the Nishnabotna Member of the Dakota Formation correlate with transgressive marine shales of the Kiowa Formation. This is a critical relationship to establish because of the need to correlate between marine and nonmarine strata that contain both geochronologic and paleoclimatic proxy data. The basal gravel facies (up to 40 m thick in western Iowa) aggraded in incised valleys during the Late Albian Kiowa-Skull Creek marine transgression. In southeastern Nebraska, basal gravels intertongue with carbonaceous mudrocks that contain diverse assemblages of Late Albian palynomorphs, including marine dinoflagellates and acritarchs. This palynomorph assemblage is characterized by occurrences of palynomorph taxa not known to range above the Albian Kiowa-Skull Creek depositional cycle elsewhere in the Western Interior, and correlates to the lowest of four generalized palynostratographic units that are comparable to other palynological sequences elsewhere in North America. Tidal rhythmites in mudrocks at the Ash Grove Cement Quarry in Louisville (Cass County), Nebraska record well-developed diurnal and semimonthly tidal cycles, and moderately well developed semiannual cycles. These tidal rhythmites are interpreted to have accumulated during rising sea level at the head of a paleoestuary that experienced at least occasional mesotidal conditions. This scenario places the gravelbearing lower part of the Nishnabotna Member of the Dakota Formation in the mouth of an incised valley of an Upper Albian transgressive systems tract deposited along a tidally influenced coast. Furthermore, it provides a depositional setting consistent with the biostratigraphic correlation of the lower part of the Nishnabotna Member of the Dakota Formation to the marine Kiowa Formation of Kansas. Copyright ??2000, SEPM (Society for Sedimentary Geology).

  10. Using inventory-based tree-ring data as a proxy for historical climate: Investigating the Pacific decadal oscillation and teleconnections

    Treesearch

    J. DeRose; S. Wang; J. Shaw

    2014-01-01

    In 2009, the Interior West Forest Inventory and Analysis (FIA) program of the U.S. Forest Service started to archive approximately 11 000 increment cores collected in the Interior West states during the periodic inventories of the 1980s and 1990s. The two primary goals for use of the data were to provide a plot-linked database of radial growth to be used for growth...

  11. An Independent Asteroseismic Analysis of the Fundamental Parameters and Internal Structure of the Solar-like Oscillator KIC 6225718

    NASA Astrophysics Data System (ADS)

    Wu, Tao; Li, Yan

    2017-09-01

    Asteroseismology is a useful tool that is usually used to probe stellar interiors and to determine stellar fundamental parameters, such as stellar mass, radius, and surface gravity. In order to probe stellar interiors, making comparisons between observations and models is usually used with the {χ }2-minimization method. The work of Wu & Li reported that the best parameter determined by the {χ }2-matching process is the acoustic radius for pure p-mode oscillations. In the present work, based on the theoretical calculations of Wu & Li, we will independently analyze the seismic observations of KIC 6225718 to determine its fundamental parameters and to investigate its interior properties. First, in order to test the method, we use it in the Sun to determine its fundamental parameters and to investigate interiors. Second, we independently determine the fundamental parameters of KIC 6225718 without any other non-seismic constraint. Therefore, those determined fundamental parameters are independent of those determined by other methods. They can be regarded as independent references in other analyses. Finally, we analyze the stellar internal structure and find that KIC 6225718 has a convective core with the size of 0.078-0.092 {R}⊙ . Its overshooting parameter {f}{ov} in the core is around 0.010. In addition, its center hydrogen {X}{{c}} is about 0.264-0.355.

  12. Cretaceous shales from the western interior of North America: sulfur/carbon ratios and sulfur-isotope composition.

    USGS Publications Warehouse

    Gautier, D.L.

    1986-01-01

    Sulphur/carbon ratios in cores of selected Cretaceous marine shales average 0.67, a value greater than that observed in recent marine sediments and much higher than global values calculated for the Cretaceous. This may be ascribed to generally low levels of bioturbation and enhanced efficiency of sulphate reduction due to low oxygen levels in Cretaceous seaways. Isotopic compositions of pyrite sulphur vary systematically with level of oxygenation of the depositional environment and therefore with organic carbon abundance and type of organic matter. Samples with >4% organic carbon are extremely depleted in 34S (mean delta 34S -31per mille) and contain hydrogen-rich organic matter. Samples containing <1.5% organic carbon display relatively 'heavy' but wide-ranging delta 34S values (-34.6 to +16.8per mille) and contain hydrogen-poor organic matter. Samples with intermediate amounts of organic carbon have average delta 34S of -25.9per mille and contain both types of organic matter. Relations between the nature of these shales, and their sedimentation rate and depositional environment are discussed.-L.C.H.

  13. Tidal constraints on the interior of Venus

    NASA Astrophysics Data System (ADS)

    Dumoulin, Caroline; Tobie, Gabriel; Verhoeven, Olivier; Rosenblatt, Pascal; Rambaux, Nicolas

    2017-04-01

    As a prospective study for a future exploration of Venus, we compute the tidal response of Venus' interior assuming various mantle compositions and temperature profiles representative of different scenarios of Venus' formation and evolution. The mantle density and seismic velocities are modeled from thermodynamical equilibria of mantle minerals and used to predict the moment of inertia, Love numbers and tidal lag characterizing the signature of the internal structure in the gravity field. The viscoelasticity of the mantle is parameterized using an Andrade rheology. From the models considered here, the moment of inertia lies in the range of 0.327 to 0.342, corresponding to a core radius of 2900 to 3450 km. The potential Love number, k2, varies from 0.25 to 0.36. Viscoelasticity of the mantle strongly increases the Love number relative to previous elastic models : depending on mantle viscosity, k2 is increased by up to 25% using a liquid core. Moreover, once a viscoelastic rheology is assumed for the core, our calculations show that the estimation of k2 from tracking of Magellan and Pioneer Venus Orbiter does not rule out the possibility of a completely solid core. Except if the solid core has a high viscosity (≥ 1018 Pa.s), solutions with both liquid and solid cores are consistent with the present-day estimation of k2. More accurate estimation of the Love number together with estimation of tidal lag by future exploration mission are required to determine the state of Venus' core and to constrain the thermo-compositional evolution of the mantle.

  14. Lithology and chronology of ice-sheet fluctuations (magnetic susceptibility of cores from the western Ross Sea)

    NASA Technical Reports Server (NTRS)

    Jennings, Anne E.

    1993-01-01

    The goals of the marine geology part of WAIS include reconstructing the chronology and areal extent of ice-sheet fluctuations and understanding the climatic and oceanographic influences on ice-sheet history. As an initial step toward attaining these goals, down-core volume magnetic susceptibility (MS) logs of piston cores from three N-S transects in the western Ross Sea are compared. The core transects are within separate petrographic provinces based on analyses of till composition. The provinces are thought to reflect the previous locations of ice streams on the shelf during the last glaciation. Magnetic susceptibility is a function of magnetic mineral composition, sediment texture, and sediment density. It is applied in the western Ross Sea for two purposes: (1) to determine whether MS data differentiates the three transects (i.e., flow lines), and thus can be used to make paleodrainage reconstructions of the late Wisconsinan ice sheet; and (2) to determine whether the MS data can aid in distinguishing basal till diamictons from diamictons of glacial-marine origin and thus, aid paleoenvironmental interpretations. A comparison of the combined data of cores in each transect is presented.

  15. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA

    Treesearch

    Joseph A. E. Stewart; David H. Wright; Katherine A. Heckman; Robert Guralnick

    2017-01-01

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species' core habitat has been lacking. Here, we report the extirpation of the American pika (Ochotona princeps...

  16. Chemical evolution of the Earth: Equilibrium or disequilibrium process?

    NASA Technical Reports Server (NTRS)

    Sato, M.

    1985-01-01

    To explain the apparent chemical incompatibility of the Earth's core and mantle or the disequilibrium process, various core forming mechanisms have been proposed, i.e., rapid disequilibrium sinking of molten iron, an oxidized core or protocore materials, and meteorite contamination of the upper mantle after separation from the core. Adopting concepts used in steady state thermodynamics, a method is devised for evaluating how elements should distribute stable in the Earth's interior for the present gradients of temperature, pressure, and gravitational acceleration. Thermochemical modeling gives useful insights into the nature of chemical evolution of the Earth without overly speculative assumptions. Further work must be done to reconcile siderophile elements, rare gases, and possible light elements in the outer core.

  17. 78 FR 73144 - Subsistence Management Program for Public Lands in Alaska; Western Interior Alaska Federal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-05

    ... Board, c/o U.S. Fish and Wildlife Service, Attention: Gene Peltola, Office of Subsistence Management....C. 3551-3586; 43 U.S.C. 1733. Dated: November 22, 2013. Gene Peltola, Assistant Regional Director, U...

  18. Radionuclide Data and Calculations and Loss-On-Ignition, X-Ray Fluorescence, and ICP-AES Data from Cores in Catchments of the Animas River, Colorado

    USGS Publications Warehouse

    Church, Stan E.; Rice, Cyndi A.; Marot, Marci E.

    2008-01-01

    The U.S. Departments of Agriculture and Interior Abandoned Mine Lands (AML) Initiative is focused on the evaluation of the effect of past mining practices on the water quality and the riparian and aquatic habitats of impacted stream reaches downstream from historical mining districts located primarily on Federal lands. This problem is manifest in the eleven western states (west of longitude 102 degrees) where the majority of hardrock mines that had past production are located on Federal lands. In areas of temperate climate and moderate to heavy precipitation, the effects of rapid chemical and physical weathering of sulfides exposed on mine-waste dumps and acidic drainage from mines have resulted in elevated metal concentrations in the stream water and stream-bed sediment. The result of these mineral weathering processes has an unquantified impact on the quality of the water and the aquatic and riparian habitats that may limit their recreational resource value. One of the confounding factors in these studies is the determination of the component of metals derived from hydrothermally altered but unmined portions of these drainage basins. Several watersheds have been studied to evaluate the effects of acid mine drainage and acid rock drainage on the near-surface environment. The Animas River watershed in southwestern Colorado contains a large number of past-producing metal mines that have affected the watershed. Beginning in October 1996, the U.S. Geological Survey (USGS) began a collaborative study of these effects under the USGS-AML Initiative. In this report, we present the radionuclide and geochemical analytical results of sediment coring during 1997-1999 from two cores from oxbow lakes 0.5 mi. upstream from the 32nd Street Bridge near Durango, Colo., and from three cores from beaver ponds within the Mineral Creek drainage basin near Silverton, Colo.

  19. THE PROPERTIES OF HEAVY ELEMENTS IN GIANT PLANET ENVELOPES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Soubiran, François; Militzer, Burkhard

    The core-accretion model for giant planet formation suggests a two-layer picture for the initial structure of Jovian planets, with heavy elements in a dense core and a thick H–He envelope. Late planetesimal accretion and core erosion could potentially enrich the H–He envelope in heavy elements, which is supported by the threefold solar metallicity that was measured in Jupiter’s atmosphere by the Galileo entry probe. In order to reproduce the observed gravitational moments of Jupiter and Saturn, models for their interiors include heavy elements, Z , in various proportions. However, their effect on the equation of state of the hydrogen–helium mixturesmore » has not been investigated beyond the ideal mixing approximation. In this article, we report results from ab initio simulations of fully interacting H–He– Z mixtures in order to characterize their equation of state and to analyze possible consequences for the interior structure and evolution of giant planets. Considering C, N, O, Si, Fe, MgO, and SiO{sub 2}, we show that the behavior of heavy elements in H–He mixtures may still be represented by an ideal mixture if the effective volumes and internal energies are chosen appropriately. In the case of oxygen, we also compute the effect on the entropy. We find the resulting changes in the temperature–pressure profile to be small. A homogeneous distribution of 2% oxygen by mass changes the temperature in Jupiter’s interior by only 80 K.« less

  20. VizieR Online Data Catalog: Behavior of heavy elements in H-He-Z mixtures (Soubiran+, 2016)

    NASA Astrophysics Data System (ADS)

    Soubiran, F.; Militzer, B.

    2016-11-01

    The core-accretion model for giant planet formation suggests a two-layer picture for the initial structure of Jovian planets, with heavy elements in a dense core and a thick H-He envelope. Late planetesimal accretion and core erosion could potentially enrich the H-He envelope in heavy elements, which is supported by the threefold solar metallicity that was measured in Jupiter's atmosphere by the Galileo entry probe. In order to reproduce the observed gravitational moments of Jupiter and Saturn, models for their interiors include heavy elements, Z, in various proportions. However, their effect on the equation of state of the hydrogen-helium mixtures has not been investigated beyond the ideal mixing approximation. In this article, we report results from ab initio simulations of fully interacting H-He-Z mixtures in order to characterize their equation of state and to analyze possible consequences for the interior structure and evolution of giant planets. Considering C, N, O, Si, Fe, MgO, and SiO2, we show that the behavior of heavy elements in H-He mixtures may still be represented by an ideal mixture if the effective volumes and internal energies are chosen appropriately. In the case of oxygen, we also compute the effect on the entropy. We find the resulting changes in the temperature-pressure profile to be small. A homogeneous distribution of 2% oxygen by mass changes the temperature in Jupiter's interior by only 80K. (3 data files).

  1. Archaeological Survey Along the Obion River: Cultural Resources Survey and Testing Below Sharon and Sidonia, Obion, Weakley, and Gibson Counties, Western Tennessee

    DTIC Science & Technology

    1987-04-22

    in some areas, especially those near Reelfoot Lake . In amny, the water table remains at or near the surface the entire summer. In others, it drops as...114) has documented early historic vugetational communities around Reelfoot Lake , immediately to the west. In brief, higher, interriverine areas were... Reelfoot Lake . N Away from the river, comparatively few major centers, or sites of any kind, have been reported in the interior Western Coastal Plain

  2. Estimating canopy bulk density and canopy base height for conifer stands in the interior Western United States using the Forest Vegetation Simulator Fire and Fuels Extension.

    Treesearch

    Seth Ex; Frederick Smith; Tara Keyser; Stephanie Rebain

    2017-01-01

    The Forest Vegetation Simulator Fire and Fuels Extension (FFE-FVS) is often used to estimate canopy bulk density (CBD) and canopy base height (CBH), which are key indicators of crown fire hazard for conifer stands in the Western United States. Estimated CBD from FFE-FVS is calculated as the maximum 4 m running mean bulk density of predefined 0.3 m thick canopy layers (...

  3. Neutron Diffraction Studies of the Atomic Vibrations of Bulk and Surface Atoms of Nanocrystalline SiC

    NASA Technical Reports Server (NTRS)

    Stelmakh, S.; Grzanka, E.; Zhao, Y.; Palosz, W.; Palosz, B.

    2004-01-01

    Thermal atomic motions of nanocrystalline Sic were characterized by two temperature atomic factors B(sub core), and B(sub shell). With the use of wide angle neutron diffraction data it was shown that at the diffraction vector above 15A(exp -1) the Wilson plots gives directly the temperature factor of the grain interior (B(sub core)). At lower Q values the slope of the Wilson plot provides information on the relative amplitudes of vibrations of the core and shell atoms.

  4. Interior Models for Saturn's Moon Titan Consistent with Cassini Observations

    NASA Astrophysics Data System (ADS)

    Castillo-Rogez, Julie

    2013-10-01

    We demonstrate that a model of Titan's interior with a core dominated by hydrated silicates can explain three major geophysical constraints available for this body: the mean moment of inertia (revised values currently in the literature or being published), tidal Love number k2, both of which were inferred from Cassini radio science observations, as well as indirect estimate of the dissipation factor inferred from Titan's orbital properties. Other models in which ice has remained partially mixed with silicates as a consequence of limited early heating fail to explain the dissipation factor. A core hydrated in silicate is difficult to maintain over the long term and may be in the process of dehydrating, which may involve significant transfer of water enriched in salts from the core to the ocean and destabilize the high-pressure ice layer. We will present possible observations that could help test this model with future observations to be obtained by the Cassini Orbiter. Acknowledgements: This work has been carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA. Government sponsorship acknowledged.

  5. Possible generation of heat from nuclear fusion in Earth's inner core.

    PubMed

    Fukuhara, Mikio

    2016-11-23

    The cause and source of the heat released from Earth's interior have not yet been determined. Some research groups have proposed that the heat is supplied by radioactive decay or by a nuclear georeactor. Here we postulate that the generation of heat is the result of three-body nuclear fusion of deuterons confined in hexagonal FeDx core-centre crystals; the reaction rate is enhanced by the combined attraction effects of high-pressure (~364 GPa) and high-temperature (~5700 K) and by the physical catalysis of neutral pions: 2 D +  2 D +  2 D → 2 1 H +  4 He + 2  + 20.85 MeV. The possible heat generation rate can be calculated as 8.12 × 10 12  J/m 3 , based on the assumption that Earth's primitive heat supply has already been exhausted. The H and He atoms produced and the anti-neutrino are incorporated as Fe-H based alloys in the H-rich portion of inner core, are released from Earth's interior to the universe, and pass through Earth, respectively.

  6. ETR BUILDING, TRA642, INTERIOR. BASEMENT. CAMERA IS AT MIDPOINT OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ETR BUILDING, TRA-642, INTERIOR. BASEMENT. CAMERA IS AT MIDPOINT OF SOUTH CORRIDOR AND FACES EAST, OPPOSITE DIRECTION FROM VIEWS ID-33-G-98 AND ID-33-G-99. STEEL DOOR AT LEFT OPENS BY ROLLING IT INTO CORRIDOR ON RAILS. TANK AT FAR END OF CORRIDOR IS EMERGENCY CORE COOLING CATCH TANK FOR A TEST LOOP. INL NEGATIVE NO. HD46-30-4. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  7. Geomagnetic field variations during the last 400 kyr in the western equatorial Pacific: Paleointensity-inclination correlation revisited

    NASA Astrophysics Data System (ADS)

    Yamazaki, T.; Kanamatsu, T.; Mizuno, S.; Hokanishi, N.; Gaffar, E. Z.

    2008-12-01

    A paleomagnetic study was conducted on four piston cores newly obtained from the West Caroline Basin in the western equatorial Pacific in order to investigate variations in paleointensity and inclination during the last 400 kyr. An inclination-intensity correlation was previously reported in this region using giant piston cores, but the quality of the paleomagnetic data of the younger end, the last ca. 300 kyr, was needed to be checked because the upper part of the giant piston cores could suffer from perturbation by oversampling. Age control is based on the oxygen-isotope ratios for one core and inter-core correlation using relative paleointensity for other cores. The mean inclinations of the four cores show negative inclination anomalies ranging from -5.2 to -11.2 degree. The western equatorial Pacific is documented as a region of a large negative inclination anomalies, and the observed values are comparable to those expected from the time-averaged field (TAF) models [Johnson and Constable, 1997; Hatakeyama and Kono, 2002]. Stacked curves of paleointensity and inclination were constructed from the four cores. It was confirmed that geomagnetic variations on the order of 10 to 100 kyrs occur in inclination as well as paleointensity. A cross-correlation analysis showed that significant in-phase correlation occurs between intensity and inclination for periods longer than about 25 kyr, and power spectra of both paleointensity and inclination variations have peaks at ~100 kyr periods. The regional paleointensity stack with higher resolution than the Sint-800 stack [Guyodo and Valet, 1999] should be useful for paleointensity-assisted chronostratigraphy.

  8. Variations of the Geomagnetic Field During the Holocene-Pleistocene: Relative Paleointensity Records From South-Western Argentina

    NASA Astrophysics Data System (ADS)

    Gogorza, C. S.

    2008-05-01

    I present a review of the research carried out by the Group of Geomagnetism at Universidad Nacional del Centro (Argentina) on paleointensity records from bottom sediments from three lakes: Escondido (Gogorza et al., 2004), Moreno (Gogorza et al., 2006) and El Trébol (Gogorza et al., 2007; Irurzun et al., 2008) (South-Western Argentina, 41° S, 71° 30'W). Based on these studies, we construct a first relative (RPI) stack for South-Western Argentina covering the last 21,000 14C years BP. The degree of down-core homogeneity of magnetic mineral content as well as magnetic mineral concentration and grain sizes vary between all lakes and are quantified by high-resolution rock magnetic measurements. Rock magnetic studies suggest that the main carriers of magnetization are ferrimagnetic minerals, predominantly pseudo-single domain magnetite The remanent magnetization at 20 mT (NRM20mT) was normalized using the anhysteric remanent magnetization at 20mT (ARM20mT), the saturation of the isothermal remanent at 20 mT (SIRM20mT) and the low field magnetic susceptibility {k}. Coherence function analysis indicates that the normalised records are free of environmental influences. Our paleointensity (NRM20mT/ ARM20mT) versus age curve shows a good agreement with published records from other parts of the world suggesting that, in suitable sediments, paleointensity of the geomagnetic field can give a globally coherent, dominantly dipolar signal. References Gogorza, C.S.G., Irurzun, M.A., Chaparro, M.A.E., Lirio, J.M., Nuñez, H., Bercoff, P.G., Sinito, A.M. Relative Paleointensity of the Geomagnetic Field over the last 21,000 years bp from Sediment Cores, Lake El Trébol, (Patagonia, Argentina). Earth, Planets and Space. V58(10), 1323-1332. 2006. Gogorza, C.S.G., Sinito, A.M., Lirio, J.M., Nuñez, H., Chaparro, M.A.E., Bertorello, H.R. Paleointensity Studies on Holocene-Pleistocene Sediments from Lake Escondido, Argentina. Physical of the Earth and Planetary Interiors, Elsevier, ISSN 0031-9201. V145, 219-238. 2004. Gogorza, C.S.G., Torcida, S., Irurzun, A., Chaparro, M.A.E., Sinito, A.M. A Pseudo-Thellier Relative Paleointensity Record in Sediments From Lake El Trébol, South Argentina. Geofísica Internacional. In Revision. 2007. Irurzun, M.A., Gogorza, C.S.G., Torcida, S., Lirio, J.M., Núnez, H., Bercoff, P., Chaparro, M.A.E., Sinito, A.M. Rock Magnetic Properties and Relative Paleointensity Stack Between 11 and 21 14C kyr B.P. from Sediment Cores, Lake Moreno (Patagonia, Argentina). In Preparation. 2008.

  9. Improving our understanding of the evolution of mountain belts via the Collisional Orogeny in the Scandinavian Caledonides (COSC) project: Results from seismic investigations and plans for the 2.5 km deep COSC-2 borehole

    NASA Astrophysics Data System (ADS)

    Juhlin, C.; Almqvist, B. S. G.; Buske, S.; Giese, R.; Hedin, P.; Lorenz, H.

    2017-12-01

    Mountain belts (orogens) have influenced, and do influence, geological processes and climatic conditions considerably, perhaps more than any other natural phenomenon. The Alpine-Himalayan mountain belt is the prime example of a collisional orogen today. However, research in an active orogen is mostly constrained to observe and interpret the expression of processes at the surface, while the driving processes act at depth, often at mid-crustal levels (20 km) and deeper. About 440 million years ago, an orogen comparable in dimension and tectonic setting to today's Alpine-Himalayan orogen was developing in what is western Scandinavia today. Since then, erosion has removed much of the overburden and exposed the deep interior of the orogen, facilitating direct observation of rocks that are deep in the crust in modern orogens. In the COSC project we study how large rock volumes (allochthons) were transported during the collision of two continents and the associated deformation. The emplacement of high-grade metamorphic allochthons during orogeny has been the focus of COSC-1 research, centered on a 2.5 km deep fully cored borehole drilled in the summer of 2014 through the lower part of the high-grade Seve Nappe Complex near the town of Åre in western Sweden. The planned COSC-2 borehole (also fully cored to 2.5 km) will complement the COSC-1 borehole and allow a 5 km deep tectonostratigraphic column of the Caledonides to be constructed. The rock volume in the proximity of the COSC-2 borehole will be imaged with a combination of very-high and high-resolution geophysical experiments, such as a combination of high frequency seismics; zero offset and walk-away vertical seismic profiling (VSP); and a sparse 3D coverage around the drill site combined with 2D seismic profiles of several kilometers length in different directions. Downhole geophysical logging will provide additional information on the in-situ rock physical properties. Data from surface surveys will be calibrated against and integrated with the borehole data and the geological interpretation of the drill core. The COSC-1 and COSC-2 boreholes will provide a field laboratory for investigating mountain building processes, how plates and rock units deform, what structures and units are formed and their physical properties.

  10. Dynamic collapses of relativistic degenerate stellar cores and radiation pressure dominated stellar interiors

    NASA Astrophysics Data System (ADS)

    Shi, Chun-Hui; Lou, Yu-Qing

    2018-04-01

    We investigate and explore self-similar dynamic radial collapses of relativistic degenerate stellar cores (RDSCs) and radiation pressure dominated stellar interiors (RPDSIs) of spherical symmetry by invoking a conventional polytropic (CP) equation of state (EoS) with a constant polytropic index γ = 4 / 3 and by allowing free-fall non-zero RDSC or RPDSI surface mass density and pressure due to their sustained physical contact with the outer surrounding stellar envelopes also in contraction. Irrespective of the physical triggering mechanisms (including, e.g., photodissociation, electron-positron pair instability, general relativistic instability etc.) for initiating such a self-similar dynamically collapsing RDSC or RPDSI embedded within a massive star, a very massive star (VMS) or a supermassive star (SMS) in contraction and by comparing with the Schwarzschild radii associated with their corresponding RDSC/RPDSI masses, the emergence of central black holes in a wide mass range appears inevitable during such RDSC/RPDSI dynamic collapses inside massive stars, VMSs, and SMSs, respectively. Radial pulsations of progenitor cores or during a stellar core collapse may well leave imprints onto collapsing RDSCs/RPDSIs towards their self-similar dynamic evolution. Massive neutron stars may form during dynamic collapses of RDSC inside massive stars in contraction under proper conditions.

  11. Face-Centred Cubic Iron: Ab Initio Calculations of Sound Velocities in the Lunar Core

    NASA Astrophysics Data System (ADS)

    Wood, M. C.; Wood, I. G.; Vočadlo, L.

    2017-12-01

    Studies, such as the reanalysis of the Apollo lunar seismograms [1], have shown that the Moon has undergone differentiation and possesses a small core. The composition of the lunar core is not well constrained, and many compositional models have been suggested including combinations of iron, nickel, and light elements such as sulphur and carbon [e.g. 1, 2, 3, 4], and other more exotic compositions [5]. Additional constraints are crucial to our understanding of the Moon, including its formation, the dynamics of its interior, and a lunar dynamo. We use ab initio molecular dynamics simulations to calculate elastic constants of face-centred cubic (fcc) iron and iron alloys and hence sound velocities at lunar core conditions, at 5-6 GPa and 1,300-1,900 K [3]. The results from these simulations will then be compared with the data from the Apollo seismograms and experimental data to help form a description of the lunar interior. [1] Weber et al. (2011) Science 331, 309-312. [2] Dasgupta et al. (2009) Geochim. Cosmochim. Acta 73, 6678-6692. [3] Antonangeli et al. (2015) Proc. Natl. Acad. Sci. U.S.A. 112, 3916-3919. [4] Righter et al. (2017) Earth Planet. Sci. Lett. 463, 323-332. [5] Wieczorek & Zuber (2002) Lunar Planet. Sci. 33, abstract 1384.

  12. A unified model of supernova driven by magnetic monopoles

    NASA Astrophysics Data System (ADS)

    Peng, Qiu-He; Liu, Jing-Jing; Chou, Chih-Kang

    2017-12-01

    In this paper, we first discuss a series of important but puzzling physical mechanisms concerning the energy source, various kinds of core collapsed supernovae explosion mechanisms during central gravitational collapse in astrophysics. We also discuss the puzzle of possible association of γ -ray burst with gravitational wave perturbation, the heat source for the molten interior of the core of the Earth and finally the puzzling problem of the cooling of white dwarfs. We then make use of the estimations for the space flux of magnetic monopoles (hereafter MMs) and nucleon decay induced by MMs (called the Rubakov-Callen (RC) effect) to obtain the luminosity due to the RC effect. In terms of the formula for this RC luminosity, we present a unified treatment for the heat source of the Earth's core, the energy source for the white dwarf interior, various kinds of core collapsed supernovae (Type II Supernova (SNII), Type Ib Supernova (SNIb), Type Ic Supernova (SNIc), Super luminous supernova (SLSN)), and the production mechanism for γ -ray burst. This unified model can also be used to reasonably explain the possible association of the short γ -ray burst detected by the Fermi γ -ray Burst Monitoring Satellite (GBM) with the LIGO gravitational wave event GW150914 in September 2015.

  13. Cheek tooth morphology and ancient mitochondrial DNA of late Pleistocene horses from the western interior of North America: Implications for the taxonomy of North American Late Pleistocene Equus

    PubMed Central

    Rodrigues, Antonia T.; Theodor, Jessica M.; Kooyman, Brian P.; Yang, Dongya Y.; Speller, Camilla F.

    2017-01-01

    Horses were a dominant component of North American Pleistocene land mammal communities and their remains are well represented in the fossil record. Despite the abundant material available for study, there is still considerable disagreement over the number of species of Equus that inhabited the different regions of the continent and on their taxonomic nomenclature. In this study, we investigated cheek tooth morphology and ancient mtDNA of late Pleistocene Equus specimens from the Western Interior of North America, with the objective of clarifying the species that lived in this region prior to the end-Pleistocene extinction. Based on the morphological and molecular data analyzed, a caballine (Equus ferus) and a non-caballine (E. conversidens) species were identified from different localities across most of the Western Interior. A second non-caballine species (E. cedralensis) was recognized from southern localities based exclusively on the morphological analyses of the cheek teeth. Notably the separation into caballine and non-caballine species was observed in the Bayesian phylogenetic analysis of ancient mtDNA as well as in the geometric morphometric analyses of the upper and lower premolars. Teeth morphologically identified as E. conversidens that yielded ancient mtDNA fall within the New World stilt-legged clade recognized in previous studies and this is the name we apply to this group. Geographic variation in morphology in the caballine species is indicated by statistically different occlusal enamel patterns in the specimens from Bluefish Caves, Yukon Territory, relative to the specimens from the other geographic regions. Whether this represents ecomorphological variation and/or a certain degree of geographic and genetic isolation of these Arctic populations requires further study. PMID:28817644

  14. Cheek tooth morphology and ancient mitochondrial DNA of late Pleistocene horses from the western interior of North America: Implications for the taxonomy of North American Late Pleistocene Equus.

    PubMed

    Barrón-Ortiz, Christina I; Rodrigues, Antonia T; Theodor, Jessica M; Kooyman, Brian P; Yang, Dongya Y; Speller, Camilla F

    2017-01-01

    Horses were a dominant component of North American Pleistocene land mammal communities and their remains are well represented in the fossil record. Despite the abundant material available for study, there is still considerable disagreement over the number of species of Equus that inhabited the different regions of the continent and on their taxonomic nomenclature. In this study, we investigated cheek tooth morphology and ancient mtDNA of late Pleistocene Equus specimens from the Western Interior of North America, with the objective of clarifying the species that lived in this region prior to the end-Pleistocene extinction. Based on the morphological and molecular data analyzed, a caballine (Equus ferus) and a non-caballine (E. conversidens) species were identified from different localities across most of the Western Interior. A second non-caballine species (E. cedralensis) was recognized from southern localities based exclusively on the morphological analyses of the cheek teeth. Notably the separation into caballine and non-caballine species was observed in the Bayesian phylogenetic analysis of ancient mtDNA as well as in the geometric morphometric analyses of the upper and lower premolars. Teeth morphologically identified as E. conversidens that yielded ancient mtDNA fall within the New World stilt-legged clade recognized in previous studies and this is the name we apply to this group. Geographic variation in morphology in the caballine species is indicated by statistically different occlusal enamel patterns in the specimens from Bluefish Caves, Yukon Territory, relative to the specimens from the other geographic regions. Whether this represents ecomorphological variation and/or a certain degree of geographic and genetic isolation of these Arctic populations requires further study.

  15. Seismic velocity and attenuation structures in the Earth's inner core

    NASA Astrophysics Data System (ADS)

    Yu, Wen-Che

    2007-12-01

    I study seismic velocity and attenuation structures in the top 400 km of the Earth's inner core along equatorial paths, velocity-attenuation relationship, and seismic anisotropy in the top of the inner core beneath Africa. Seismic observations exhibit "east-west" hemispheric differences in seismic velocity, attenuation, and anisotropy. Joint modeling of the PKiKP-PKIKP and PKPbc-PKIKP phases is used to constrain seismic velocity and attenuation structures in the top 400 km of the inner core for the eastern and western hemispheres. The velocity and attenuation models for the western hemisphere are simple, having a constant velocity gradient and a Q value of 600 in the top 400 km of the inner core. The velocity and attenuation models for the eastern hemisphere appear complex. The velocity model for the eastern hemisphere has a small velocity gradient in the top 235 km, a steeper velocity gradient at the depth range of 235 - 375 km, and a gradient similar to PREM in the deeper portion of the inner core. The attenuation model for the eastern hemisphere has a Q value of 300 in the top 300 km and a Q value of 600 in the deeper portion of the inner core. The study of velocity-attenuation relationship reveals that inner core is anisotropic in both velocity and attenuation, and the direction of high attenuation corresponding to that of high velocity. I hypothesize that the hexagonal close packed (hcp) iron crystal is anisotropic in attenuation, with the axis of high attenuation corresponding to that of high velocity. Anisotropy in the top of the inner core beneath Africa is complex. Beneath eastern Africa, the thickness of the isotropic upper inner core is about 0 km. Beneath central and western Africa, the thickness of the isotropic upper inner core increases from 20 to 50 km. The velocity increase across the isotropic upper inner core and anisotropic lower inner core boundary is sharp, laterally varying from 1.6% - 2.2%. The attenuation model has a Q value of 600 for the isotropic upper inner core and 150 to 400 for the anisotropic lower inner core.

  16. A new Late Weichselian and Holocene marine chronology for the western Svalbard slope 30,000-0 cal years BP

    NASA Astrophysics Data System (ADS)

    Jessen, Simon P.; Rasmussen, Tine L.; Nielsen, Tove; Solheim, Anders

    2010-05-01

    Data have been compiled from eleven sediment cores from 76° to 80°N on the western Svalbard slope. The cores are from water depths between 630 and 1880 m and show clear similarities in lithology and magnetic susceptibility. All cores penetrated into mass transported sediments from glacigenic debris flow events and turbidity flow events. The mass transport probably occurred when the ice reached the shelf edge. The deposits date between 24,080 ± 150 and 23,550 ± 185 calibrated (cal) years BP. The records also include laminated, fine grained sediments interpreted as deposits from sediment-laden meltwater plumes dated between 14,780 ± 220 and 14,300 ± 260 cal years BP. In Holocene sediments a diatom-rich fine grained layer dates 10,100 ± 150 to 9840 ± 200 cal years BP. The eleven cores have been stacked into one record with absolute age control from 35 AMS 14C dates. Together with oxygen isotope stratigraphy and contents of ice rafted detritus the stacked record provides a useful chronology tool for cores on the western Svalbard slope. Our study improves the age control of earlier well documented glacial events and shows that the maximum glacial state and the onset of the deglaciation both occurred 2500-3000 years earlier than previously reconstructed for the western Svalbard margin. The results indicate that during the last 30,000 years advance and retreat of the Svalbard-Barents Sea Ice Sheet was closely linked to the flow of Atlantic Water and Polar Water over the margin.

  17. Cretaceous paleoceanography of the western North Atlantic Ocean

    USGS Publications Warehouse

    Arthur, Michael A.; Dean, Walter E.

    1986-01-01

    In this paper we summarize available information on the Cretaceous lithostratigraphy and paleoceanography of the western North Atlantic. The data and some of our interpretations draw in large part on papers published in the Deep Sea Drilling Project (DSDP) volumes. We have attempted to cite relevant references when possible, but space limitations make it difficult to give proper credit to all sources; we apologize for any omissions.Organic carbon (Corg) and carbonate (CaCO3) analyses were tabulated for each site from papers in the DSDP Initial Report volumes and other published works (e.g., Summerhayes,1981). Corg, CaCO3, and non-CaCO3 mass accumulation rates (MARS) were calculated using core by core averages of component percentages for the more continuously cored sites; core averages for wet bulk density and porosity (from DSDP data files); biostratigraphies of de Graciansky and others (1982), Roth and Bowdler (1981), and Cool (1982); and the time scales of the Decade of North American Geology (Palmer, 1983; Kent and Gradstein, this volume) or Harland and others (1982; see Plate 1).Backtracked paleodepths for western North Atlantic DSDP Sites from Tucholke and Vogt (1979) with the revised stratigraphy of de Graciansky and others (1982) were used in plotting Corg and CaCO3 in Figures 2, 3, 4 and 5 (see also Thierstein, 1979).Backtracking curves of seafloor paleodepth versus age (Sclater and others, 1977; Tucholke and Vogt, 1979) for selected western North Atlantic DSDP sites. Average CaCO3 concentrations per core are shown by code number

  18. The postcollapse core of M15 imaged with the HST planetary camera

    NASA Technical Reports Server (NTRS)

    Lauer, Tod R.; Holtzman, Jon A.; Faber, S. M.; Baum, William A.; Currie, Douglas G.; Ewald, S. P.; Groth, Edward J.; Hester, J. Jeff; Kelsall, T.

    1991-01-01

    It is shown here that, despite the severe spherical aberration present in the HST, the Wide Field/Planetary Camera (WFPC) images still present useful high-resolution information on M15, the classic candidate for a cluster with a collapsed core. The stars in M15 have been resolved down to the main-sequence turnoff and have been subtracted from the images. The remaining faint, unresolved stars form a diffuse background with a surprisingly large core with r(c) = 0.13 pc. The existence of a large core interior to the power-law cusp may imply that M15 has evolved well past maximum core collapse and may rule out the presence of a massive central black hole as well.

  19. BLM forest lands report -- 2006 status and condition

    Treesearch

    Tim Bottomley; Jim Menlove

    2006-01-01

    The Bureau of Land Management (BLM), an agency within the U.S. Department of the Interior (DOI), administers over 261 million surface acres of public land in the western United States, including Alaska. Approximately 69 million acres, or 26 percent, are classified as forested.

  20. Early Stages Of Biome Shift in Boreal Alaska: Climate Sensitivity of Tree Growth and Accelerated Tree Mortality

    NASA Astrophysics Data System (ADS)

    Juday, G. P.; Grant, T.; Alix, C. M.; Spencer, D. L.; Beck, P. S.

    2012-12-01

    The boreal forest region of Alaska is characterized by a major east-west climate gradient, in addition to a widely appreciated north-south gradient. Low elevations of the eastern and central Interior experience warm summer temperatures and low annual precipitation, while coastal western Alaska has cool summer temperatures and greater precipitation. In the Interior the four dominant tree species of white and black spruce, aspen, and Alaska birch on low elevation sites nearly all register a strong negative radial growth relationship to summer temperatures, concentrated in May and July. Precipitation, particularly in late winter and midsummer, plays a supplemental role as a positive factor in growth. Floodplain white spruce along the Yukon and Kuskokwim Rivers transition from negative temperature response to positive response in western Alaska near the tree limit. Populations of white spruce on treeline sites display both negative growth response to July temperature and positive response to spring temperatures, with the negative response dominant in the east and the positive response dominant in the west. Across boreal Alaska summer temperatures increased abruptly in 1974, and have remained at historically high levels since. Correspondingly, climatic favorability for radial growth of Interior trees on most low elevation sites has been at extreme low levels particularly in the 21st century. Satellite-based NDVI coverage confirms that forest growth reduction is widespread in boreal Alaska since the 1980s. Defoliating and wood boring insects have reached outbreak population levels across most of boreal Alaska, partly from release of direct temperature control on the insects and partly from increased tree host susceptibility. Major outbreak species include aspen leaf miner, spruce engraver beetle, and spruce budworm. About a dozen tall willow species have been subjected to widespread attack by willow leaf blotch miner, and a new disease and defoliating insect have spread rapidly in alder shrubs, so nearly all woody species face health challenges. Temperatures and precipitation on many Interior sites are now at or beyond tolerance limits for white spruce, aspen, and Alaska birch. Two episodes of acute drought injury were widespread in birch during the last decade. Deficits in climate predicted tree growth are synchronous with the major insect outbreaks as recorded in insect trapping records and aerial surveys of area affected. Over the past 25 years tree mortality of 50% or more occurred in nearly all long-term monitoring plots in mature stands on productive sites in the Interior, but to date trees have successfully regenerated on most disturbed sites. These environmental changes and tree responses, including opposite responses, are coherent, and consistent with early stages of a biome shift eliminating boreal forest on dry Interior sites, and emergence of a new climate optimum zone in western Alaska currently only sparsely populated with forest.

  1. GRAIL Twin Spacecraft -- Crust to Core Artist Concept

    NASA Image and Video Library

    2009-05-18

    The Gravity Recovery and Interior Laboratory GRAIL mission utilizes the technique of twin spacecraft flying in formation with a known altitude above the lunar surface and known separation distance to investigate the gravity field of the moon.

  2. Deposition and regional distribution of HCHs and p,p'-DDX in the western and southern Tibetan Plateau: records from a lake sediment core and the surface soils.

    PubMed

    Tao, Yu-Qiang; Lei, Guo-Liang; Xue, Bin; Yao, Shu-Chun; Pu, Yang; Zhang, Hu-Cai

    2014-02-01

    Tibetan Plateau is the world's highest plateau, which provides a unique location for the investigation of global fractionation of organochlorine pesticides (OCPs). In this study, deposition and regional distribution of HCHs and p,p'-DDX in the western and southern Tibetan Plateau were investigated by the records from a sediment core of Lake Zige Tangco and 24 surface soils. Concentration of ΣHCHs in the surface soils of the western Tibetan Plateau was much higher than that of the southern part. Maximum fluxes of α-, β-, and δ-HCH in the sediment core were 9.0, 222, and 21 pg cm(-2) year(-1), respectively, which appeared in the mid-1960s. Significant correlations were observed between concentrations of α- and β-HCH in both the surface soils and the sediment core. Concentrations of both α- and β-HCH increased with the inverse of the average annual temperature of these sites. γ-HCH became the dominant isomer of HCHs after the late 1970s, and reached the maximum flux of 160 pg cm(-2) year(-1) in the early 1990s. There were no significant correlations between concentrations of γ-HCH and the other isomers in both the surface soils and the sediment core. The results suggested that there was input of Lindane at scattered sites in this area. In contrast to ΣHCHs, concentration of Σp,p'-DDX in the surface soils of the southern part was much higher than that of the western part. Maximum flux of Σp,p'-DDX was 44 pg cm(-2) year(-1), which appeared in the mid-1960s. Local emission of p,p'-DDT was found at scattered sites. This study provides novel data and knowledge for the OCPs in the western and southern Tibetan Plateau, which will help understand the global fractionation of OCPs in remote alpine regions.

  3. Isotopic evaluation of ocean circulation in the Late Cretaceous North American seaway

    NASA Astrophysics Data System (ADS)

    Coulson, Alan B.; Kohn, Matthew J.; Barrick, Reese E.

    2011-12-01

    During the mid- and Late Cretaceous period, North America was split by the north-south oriented Western Interior Seaway. Its role in creating and maintaining Late Cretaceous global greenhouse conditions remains unclear. Different palaeoceanographic reconstructions portray diverse circulation patterns. The southward extent of relatively cool, low-salinity, low-δ18O surface waters critically distinguishes among these models, but past studies of invertebrates could not independently assess water temperature and isotopic compositions. Here we present oxygen isotopes in biophosphate from coeval marine turtle and fish fossils from western Kansas, representing the east central seaway, and from the Mississippi embayment, representing the marginal Tethys Ocean. Our analyses yield precise seawater isotopic values and geographic temperature differences during the main transition from the Coniacian to the early Campanian age (87-82 Myr), and indicate that the seaway oxygen isotope value and salinity were 2‰ and 3‰ lower, respectively, than in the marginal Tethys Ocean. We infer that the influence of northern freshwater probably reached as far south as Kansas. Our revised values imply relatively large temperature differences between the Mississippi embayment and central seaway, explain the documented regional latitudinal palaeobiogeographic zonation and support models with relatively little inflow of surface waters from the Tethys Ocean to the Western Interior Seaway.

  4. Tidal constraints on the interior of Venus

    NASA Astrophysics Data System (ADS)

    Dumoulin, C.; Tobie, G.; Verhoeven, O.; Rosenblatt, P.; Rambaux, N.

    2017-06-01

    As a prospective study for a future exploration of Venus, we compute the tidal response of Venus' interior assuming various mantle compositions and temperature profiles representative of different scenarios of Venus' formation and evolution. The mantle density and seismic velocities are modeled from thermodynamical equilibria of mantle minerals and used to predict the moment of inertia, Love numbers, and tide-induced phase lag characterizing the signature of the internal structure in the gravity field. The viscoelasticity of the mantle is parameterized using an Andrade rheology. From the models considered here, the moment of inertia lies in the range of 0.327 to 0.342, corresponding to a core radius of 2900 to 3450 km. Viscoelasticity of the mantle strongly increases the potential Love number relative to previously published elastic models. Due to the anelasticity effects, we show that the possibility of a completely solid metal core inside Venus cannot be ruled out based on the available estimate of k2 from the Magellan mission (Konopliv and Yoder, 1996). A Love number k2 lower than 0.27 would indicate the presence of a fully solid iron core, while for larger values, solutions with an entirely or partially liquid core are possible. Precise determination of the Love numbers, k2 and h2, together with an estimate of the tidal phase lag, are required to determine the state and size of the core, as well as the composition and viscosity of the mantle.

  5. Tidal constraints on the interior of Venus

    NASA Astrophysics Data System (ADS)

    Dumoulin, C.; Tobie, G.; Verhoeven, O.; Rosenblatt, P.; Rambaux, N.

    2017-12-01

    As a prospective study for a future exploration of Venus, we compute the tidal response of Venus' interior assuming various mantle compositions and temperature profiles representative of different scenarios of Venus' formation and evolution. The mantle density and seismic velocities are modeled from thermodynamical equilibria of mantle minerals and used to predict the moment of inertia, Love numbers, and tide-induced phase lag characterizing the signature of the internal structure in the gravity field. The viscoelasticity of the mantle is parameterized using an Andrade rheology. From the models considered here, the moment of inertia lies in the range of 0.327 to 0.342, corresponding to a core radius of 2900 to 3450 km. Viscoelasticity of the mantle strongly increases the potential Love number relative to previously published elastic models. Due to the anelasticity effects, we show that the possibility of a completely solid metal core inside Venus cannot be ruled out based on the available estimate of k2 from the Magellan mission (Konopliv and Yoder, 1996). A Love number k2 lower than 0.27 would indicate the presence of a fully solid iron core, while for larger values, solutions with an entirely or partially liquid core are possible. Precise determination of the Love numbers, k2 and h2, together with an estimate of the tidal phase lag, are required to determine the state and size of the core, as well as the composition and viscosity of the mantle.

  6. Neutron shielding panels for reactor pressure vessels

    DOEpatents

    Singleton, Norman R [Murrysville, PA

    2011-11-22

    In a nuclear reactor neutron panels varying in thickness in the circumferential direction are disposed at spaced circumferential locations around the reactor core so that the greatest radial thickness is at the point of highest fluence with lesser thicknesses at adjacent locations where the fluence level is lower. The neutron panels are disposed between the core barrel and the interior of the reactor vessel to maintain radiation exposure to the vessel within acceptable limits.

  7. 30 CFR 784.14 - Hydrologic information.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Hydrologic information. 784.14 Section 784.14... Hydrologic information. (a) Sampling and analysis. All water quality analyses performed to meet the... Center, U.S. Department of the Interior, Building 10, Parkway Center, Pittsburgh, Pa.; at the OSM Western...

  8. 30 CFR 784.14 - Hydrologic information.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Hydrologic information. 784.14 Section 784.14... Hydrologic information. (a) Sampling and analysis. All water quality analyses performed to meet the... Center, U.S. Department of the Interior, Building 10, Parkway Center, Pittsburgh, Pa.; at the OSM Western...

  9. Recent climatic, cryospheric, and hydrological changes over the interior of western Canada: a review and synthesis

    NASA Astrophysics Data System (ADS)

    DeBeer, Chris M.; Wheater, Howard S.; Carey, Sean K.; Chun, Kwok P.

    2016-04-01

    It is well established that the Earth's climate system has warmed significantly over the past several decades, and in association there have been widespread changes in various other Earth system components. This has been especially prevalent in the cold regions of the northern mid- to high latitudes. Examples of these changes can be found within the western and northern interior of Canada, a region that exemplifies the scientific and societal issues faced in many other similar parts of the world, and where impacts have global-scale consequences. This region has been the geographic focus of a large amount of previous research on changing climatic, cryospheric, and hydrological regimes in recent decades, while current initiatives such as the Changing Cold Regions Network (CCRN) introduced in this review seek to further develop the understanding and diagnosis of this change and hence improve the capacity to predict future change. This paper provides a comprehensive review of the observed changes in various Earth system components and a concise and up-to-date regional picture of some of the temporal trends over the interior of western Canada since the mid- or late 20th century. The focus is on air temperature, precipitation, seasonal snow cover, mountain glaciers, permafrost, freshwater ice cover, and river discharge. Important long-term observational networks and data sets are described, and qualitative linkages among the changing components are highlighted. Increases in air temperature are the most notable changes within the domain, rising on average 2 °C throughout the western interior since 1950. This increase in air temperature is associated with hydrologically important changes to precipitation regimes and unambiguous declines in snow cover depth, persistence, and spatial extent. Consequences of warming air temperatures have caused mountain glaciers to recede at all latitudes, permafrost to thaw at its southern limit, and active layers over permafrost to thicken. Despite these changes, integrated effects on stream flow are complex and often offsetting. Following a review of the current literature, we provide insight from a network of northern research catchments and other sites detailing how climate change confounds hydrological responses at smaller scales, and we recommend several priority research areas that will be a focus of continued work in CCRN. Given the complex interactions and process responses to climate change, it is argued that further conceptual understanding and quantitative diagnosis of the mechanisms of change over a range of scales is required before projections of future change can be made with confidence.

  10. Paleohydrology of tropical South America and paleoceanography of the tropical Atlantic as deduced from two new sediment cores on the Brazilian continental slope

    NASA Astrophysics Data System (ADS)

    Nace, T.; Baker, P. A.; Dwyer, G. S.; Silva, C. G.; Hollander, D. J.; Rigsby, C. A.; Giosan, L.; Burns, S. J.

    2011-12-01

    Paleoclimate/paleoceanographic reconstructions of the Amazon Basin, Brazilian Nordeste, and western equatorial Atlantic have been undertaken on two new sediment cores located on the Brazilian continental slope (Core CDH-5 at 1708 mbsl, 4N, 48W, 32m long, ~30 ka record; Core CDH-86 at 3708 mbsl, 0N/S, 44W, 30m long, ~100ka record). High-resolution XRF analyses of Fe, Ti, and Ca are used to define the paleohydrologic history of the adjacent continent at both sites. Large and abrupt excursions of Ti/Ca ratios are observed in both cores, but are significantly better defined in the southern core, representative of Nordeste conditions. In this core there are a total of 9 Ti/Ca excursions, the oldest recovered dating to ~98ka. These excursions correlate well with Heinrich events from the North Atlantic. High-resolution stable oxygen isotopic analysis and Mg/Ca paleothermometry undertaken on the near-surface-dwelling planktic foraminiferal species Globierinoides ruber provide a picture of paleoceanographic forcings in the western equatorial Atlantic. The northern and southern cores respectively exhibit rapid warming of ~3C and ~3.5C between the last glacial maximum and the early Holocene. Furthermore, in almost all cases, during the last glacial stage, there was a 0.5C to 2C warming of the western equatorial Atlantic during the periods of high Ti/Ca ratios that correlate with Heinrich events. Thus, as observed in some previous studies, the western equatorial Atlantic was warm and the adjacent southern tropical continent was wet at the same time that the high-latitude North Atlantic was cold. The largely accepted paradigm is that Northern hemisphere cold events result in a southward migration of the Intertropical Convergence Zone (ITCZ), contributing to drier conditions at the northern extent of the ITCZ annual range (Cariaco Basin) and increased precipitation in the southern tropics of South America. The ITCZ appears to have been influenced by millennial variability of North-South Atlantic sea surface temperature (SST) gradients, with a southward migration in the zone of maximum tropical SSTs leading to a southward migration of the ITCZ. It is commonly modeled that Northern Hemisphere stadial events are associated with a SST increase in the equatorial Atlantic and a cooling of the North Atlantic. Our records of increased runoff synchronous with warmer SSTs in the western equatorial Atlantic coincident with cold Heinrich events of the north Atlantic strongly support this interpretation.

  11. Osteopathic approach to implementing and promoting interprofessional education.

    PubMed

    Mackintosh, Susan E; Adams, Clinton E; Singer-Chang, Gail; Hruby, Raymond J

    2011-04-01

    Multidisciplinary fragmentation contributes to myriad medical errors and as many as 98,000 patient deaths per year. The Institute of Medicine has proposed steps to improve healthcare delivery, including providing more opportunities for interdisciplinary training. The authors describe the interprofessional education (IPE) program at Western University of Health Sciences (WesternU) in Pomona, California. In 2007, 9 colleges at WesternU-including the College of Osteopathic Medicine of the Pacific-undertook an IPE initiative that resulted in creation of a 3-phase program. Part of the IPE development process involved identifying core competencies that were nontechnical and nonclinical and common to all healthcare professions. The IPE development and implementation process and the identified competencies were analyzed for their relationship to the tenets of osteopathic medicine and the core competencies of osteopathic medical education. Although these tenets and core competencies were not intentionally used in the development process of the WesternU IPE program, the analysis revealed that the major components of the program are congruent with the framework of osteopathic principles and practice. The osteopathic medical profession's founding principles, broad-based perspective, and health-promoting tenets put the profession in a position to emerge as one of the leading forces in IPE.

  12. GRAIL Mission Briefing

    NASA Image and Video Library

    2011-08-25

    Leesa Hubbard, teacher in residence, Sally Ride Science, San Diego, speaks at a press conference about the upcoming launch to the moon of the Gravity Recovery and Interior Laboratory (GRAIL) mission, Thursday, Aug. 25, 2011 in Washington. GRAIL's primary science objectives are to determine the structure of the lunar interior, from crust to core, and to advance understanding of the thermal evolution of the moon. The mission will place two spacecraft into the same orbit around the moon which will gather information about the its gravitational field enabling scientists to create a high-resolution map. Photo Credit: (NASA/Carla Cioffi)

  13. GRAIL Mission Briefing

    NASA Image and Video Library

    2011-08-25

    Jim Green (left), director, Planetary Science Division at NASA Headquarters, speaks at a press conference about the upcoming launch to the moon of the Gravity Recovery and Interior Laboratory (GRAIL) mission, Thursday, Aug. 25, 2011 in Washington. GRAIL's primary science objectives are to determine the structure of the lunar interior, from crust to core, and to advance understanding of the thermal evolution of the moon. The mission will place two spacecraft into the same orbit around the moon which will gather information about the its gravitational field enabling scientists to create a high-resolution map. Photo Credit: (NASA/Carla Cioffi)

  14. GRAIL Mission Briefing

    NASA Image and Video Library

    2011-08-25

    Jim Green, director, Planetary Science Division at NASA Headquarters, speaks at a press conference about the upcoming launch to the moon of the Gravity Recovery and Interior Laboratory (GRAIL) mission, Thursday, Aug. 25, 2011 in Washington. GRAIL's primary science objectives are to determine the structure of the lunar interior, from crust to core, and to advance understanding of the thermal evolution of the moon. The mission will place two spacecraft into the same orbit around the moon which will gather information about the its gravitational field enabling scientists to create a high-resolution map. Photo Credit: (NASA/Carla Cioffi)

  15. Development of assembly techniques for fire resistant aircraft interior panels

    NASA Technical Reports Server (NTRS)

    Lee, S. C. S.

    1978-01-01

    Ten NASA Type A fire resistant aircraft interior panels were fabricated and tested to develop assembly techniques. These techiques were used in the construction of a full scale lavatory test structure for flame propagation testing. The Type A panel is of sandwich construction consisting of Nomex honeycomb filled with quinone dioxime foam, and bismaleimide/glass face sheets bonded to the core with polyimide film adhesive. The materials selected and the assembly techniques developed for the lavatory test structure were designed for obtaining maximum fire containment with minimum smoke and toxic emission.

  16. Phase Equilibrium Investigations of Planetary Materials

    NASA Technical Reports Server (NTRS)

    Grove, T. L.

    1997-01-01

    This grant provided funds to carry out experimental studies designed to illuminate the conditions of melting and chemical differentiation that has occurred in planetary interiors. Studies focused on the conditions of mare basalt generation in the moon's interior and on processes that led to core formation in the Shergottite Parent Body (Mars). Studies also examined physical processes that could lead to the segregation of metal-rich sulfide melts in an olivine-rich solid matrix. The major results of each paper are discussed below and copies of the papers are attached as Appendix I.

  17. Anatomy of a metamorphic core complex: seismic refraction/wide-angle reflection profiling in southeastern California and western Arizona

    USGS Publications Warehouse

    McCarthy, J.; Larkin, S.P.; Fuis, G.S.; Simpson, R.W.; Howard, K.A.

    1991-01-01

    The metamorphic core complex belt in southeastern California and western Arizona is a NW-SE trending zone of unusually large Tertiary extension and uplift. Midcrustal rocks exposed in this belt raise questions about the crustal thickness, crustal structure, and the tectonic evolution of the region. Three seismic refraction/wide-angle reflection profiles were collected to address these issues. The results presented here, which focus on the Whipple and Buckskin-Rawhide mountains, yield a consistent three-dimensiional image of this part of the metamorphic core complex belt. The final model consists of a thin veneer (<2 km) of upper plate and fractured lower plate rocks (1.5-5.5 km s-1) overlying a fairly homogeneous basement (~6.0 km s-1) and a localized high-velocity (6.4 km s -1) body situated beneath the western Whipple Mountains. A prominent midcrustal reflection is identified beneath the Whipple and Buckskin Rawhide mountains between 10 and 20km depth. -from Authors

  18. Integrated management of timber-elk-cattle: interior forests of western North America.

    Treesearch

    J.W. Thomas; D.A. Leckenby; L. Jack [and others]. Lyon

    1988-01-01

    The need for and the evaluation of elk-habitat evaluation models are reviewed, and a state-of-the-art example is presented that incorporates distribution of elk-habitat use related to distance from cover/forage edges, distance from roads, cover quality, and forage quantity and quality.

  19. Diet composition, dry matter intake and diet overlap of mule deer, elk and cattle.

    Treesearch

    Scott L. Findholt; Bruce K. Johnson; Daalkhaijav Damiran; Tim DelCurto; John G. Kie

    2004-01-01

    Mule deer (Odocoileus hemionus), elk (Cervus elaphus) and cattle share rangeland throughout much of interior western North America. Considerable debate exists about the degree to which facilitation or competition occurs for forage between these three species (Nelson 1982, Wisdom and Thomas 1996, Miller 2002).

  20. 76 FR 55155 - Final Environmental Impact Statement for the Proposed Keystone XL Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-06

    ... proposed Project that is designed to transport crude oil produced from oil sands in the Western Canadian... of Energy, Defense, Transportation, Homeland Security, Justice, Interior, and Commerce, and the..., alternative pipeline designs, and alternative sites for aboveground facilities; the potential impacts of the...

  1. 77 FR 60373 - Monroe Mountain Aspen Ecosystems Restoration Project Fishlake National Forest; Sevier and Piute...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... support the highest level of biodiversity for interior western forests. Productivity of aspen ecosystem... intolerant and sprouts heavily following disturbance; such as fire, which removes shading effects in areas..., mechanical treatments in Inventoried Roadless Areas, effects on wildlife species, effects to watersheds and...

  2. 30 CFR 917.15 - Approval of Kentucky regulatory program amendments.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... amendments. 917.15 Section 917.15 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE KENTUCKY... Production After Mining;” “Estimated Crop Yields on Prime Farmland Soils in Western Kentucky Coalfields...

  3. 30 CFR 917.15 - Approval of Kentucky regulatory program amendments.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... amendments. 917.15 Section 917.15 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE KENTUCKY... Production After Mining;” “Estimated Crop Yields on Prime Farmland Soils in Western Kentucky Coalfields...

  4. 30 CFR 917.15 - Approval of Kentucky regulatory program amendments.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... amendments. 917.15 Section 917.15 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE KENTUCKY... Production After Mining;” “Estimated Crop Yields on Prime Farmland Soils in Western Kentucky Coalfields...

  5. 30 CFR 917.15 - Approval of Kentucky regulatory program amendments.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... amendments. 917.15 Section 917.15 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE KENTUCKY... Production After Mining;” “Estimated Crop Yields on Prime Farmland Soils in Western Kentucky Coalfields...

  6. 30 CFR 917.15 - Approval of Kentucky regulatory program amendments.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... amendments. 917.15 Section 917.15 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE KENTUCKY... Production After Mining;” “Estimated Crop Yields on Prime Farmland Soils in Western Kentucky Coalfields...

  7. Introduction

    Treesearch

    Norbert V. DeByle; Robert P. Winokur

    1985-01-01

    Quaking or trembling aspen (Populus tremuloides Michx.) is the only aspen in western North America. Therefore, in this part of the continent, it is commonly and correctly referred to simply as "aspen". Throughout much of the interior West, it is the only upland hardwood. Aspen occupies millions of acres, and, in some states, it is the most...

  8. The Prairie Schoolhouse.

    ERIC Educational Resources Information Center

    Campbell, John Martin

    This book documents the history of the prairie schoolhouse through text and photographs. The prairie schoolhouse was a product of the Western Homestead Era, those years beginning late in the 19th century when the federally owned grass prairies east of the Rockies and the sagebrush country of the interior Northwest were opened to farming.…

  9. Effects of climate change on terrestrial animals [Chapter 9

    Treesearch

    Megan M. Friggens; Mary I. Williams; Karen E. Bagne; Tosha T. Wixom; Samuel A. Cushman

    2018-01-01

    The Intermountain Adaptation Partnership (IAP) region encompasses a high diversity of grassland, shrubland, and forest habitats across a broad range of elevational gradients, supporting high biodiversity in the interior western United States. Terrestrial species comprise a wide range of life forms, each expressing varying levels of habitat specialization and life...

  10. Measurements of Mercury's spin state and inferences about its interior

    NASA Astrophysics Data System (ADS)

    Margot, J.; Padovan, S.; Peale, S. J.; Solomon, S. C.

    2011-12-01

    Over the past nine years we have used the Green Bank Telescope (GBT) in conjunction with the Goldstone Solar System Radar (GSSR) to characterize the spin state and interior of Mercury. We implemented a technique [1,2] that provides instantaneous spin rate measurements with 10-5 fractional precision and spin orientation measurements at the arcsecond level. On the basis of measurements at 21 distinct epochs between 2002 and 2006, we found observational evidence that Mercury closely follows a Cassini state and that it exhibits forced librations in longitude [3], as predicted by theory [4,5]. A long-period (˜12 year) libration signature may be present in the data. Since 2006 we have secured measurements at 11 additional epochs (out of 23 attempts). We are in the process of re-analyzing the entire set of observations with the goals of (1) refining the determination of the obliquity and of the libration amplitude, two parameters that are critical in the determination of the core size; (2) confirming the presence or absence of a long-period libration component, with the prospect of elucidating the excitation mechanism; (3) quantifying deviations of the pole from the strict Cassini state, which could inform us about dissipation due to solid-body tides and core-mantle interactions. Our first goal is particularly important now that MESSENGER is securing measurements of the low-degree gravitational harmonics with an expected precision of better than 1%. The core-size error budget indicates that the precision of the ground-based estimates of obliquity and librations will ultimately dictate the quality of the core size determination, as well as the attendant inferences regarding the interior structure, thermal evolution, and magnetic field generation of the planet. [1] Green, in Radar Astronomy, McGraw-Hill, 1968. [2] Holin, Radiophys. Quant. Elec. 31, 1988. [3] Margot et al, Science 316, 2007. [4] Peale, Nature 262, 1976. [5] Peale, in Mercury, U. of Arizona Press, 1988.

  11. Possible generation of heat from nuclear fusion in Earth’s inner core

    PubMed Central

    Fukuhara, Mikio

    2016-01-01

    The cause and source of the heat released from Earth’s interior have not yet been determined. Some research groups have proposed that the heat is supplied by radioactive decay or by a nuclear georeactor. Here we postulate that the generation of heat is the result of three-body nuclear fusion of deuterons confined in hexagonal FeDx core-centre crystals; the reaction rate is enhanced by the combined attraction effects of high-pressure (~364 GPa) and high-temperature (~5700 K) and by the physical catalysis of neutral pions: 2D + 2D + 2D → 21H + 4He + 2  + 20.85 MeV. The possible heat generation rate can be calculated as 8.12 × 1012 J/m3, based on the assumption that Earth’s primitive heat supply has already been exhausted. The H and He atoms produced and the anti-neutrino are incorporated as Fe-H based alloys in the H-rich portion of inner core, are released from Earth’s interior to the universe, and pass through Earth, respectively. PMID:27876860

  12. Gravitational evidence for an undifferentiated Callisto.

    PubMed

    Anderson, J D; Lau, E L; Sjogren, W L; Schubert, G; Moore, W B

    1997-05-15

    Before the arrival of the Galileo spacecraft at Jupiter, models for the interior structure of the four galilean satellites--Io, Europa, Ganymede and Callisto-ranged from uniform mixtures of rock and ice (that is, undifferentiated objects) or rocky cores surrounded by a mantle of water ice. Now it appears that Io has a large metallic core and that Ganymede is strongly differentiated, most probably into a three-layer structure consisting of a metallic core, a silicate mantle and a deep outer layer of ice. Direct information on the interior structure of Callisto determined from previous spacecraft fly-bys was essentially limited to an estimate of the mean density being intermediate between pure ice and pure rock. Here we report measurements of Callisto's gravitational field which reveal that, in contrast to Io and Ganymede, this galilean satellite is most probably a homogeneous object consisting of a solar mixture of 40% compressed ice and 60% rock (including iron and iron sulphide). Callisto's undifferentiated state is consistent with the apparent lack of an intrinsic magnetic field, and indicates that the outermost galilean satellite has not experienced a heating phase sufficiently high to separate its rock and metal components from the lighter ices.

  13. Age of the Lava Creek supereruption and magma chamber assembly at Yellowstone based on 40Ar/39Ar and U-Pb dating of sanidine and zircon crystals

    USGS Publications Warehouse

    Matthews, Naomi E.; Vazquez, Jorge A.; Calvert, Andrew T.

    2015-01-01

    The last supereruption from the Yellowstone Plateau formed Yellowstone caldera and ejected the >1000 km3 of rhyolite that composes the Lava Creek Tuff. Tephra from the Lava Creek eruption is a key Quaternary chronostratigraphic marker, in particular for dating the deposition of mid Pleistocene glacial and pluvial deposits in western North America. To resolve the timing of eruption and crystallization history for the Lava Creek magma, we performed (1) 40Ar/39Ar dating of single sanidine crystals to delimit eruption age and (2) ion microprobe U-Pb and trace-element analyses of the crystal faces and interiors of single zircons to date the interval of zircon crystallization and characterize magmatic evolution. Sanidines from the two informal members composing Lava Creek Tuff yield a preferred 40Ar/39Ar isochron date of 631.3 ± 4.3 ka. Crystal faces on zircons from both members yield a weighted mean 206Pb/238U date of 626.5 ± 5.8 ka, and have trace element concentrations that vary with the eruptive stratigraphy. Zircon interiors yield a mean 206Pb/238U date of 659.8 ± 5.5 ka, and reveal reverse and/or oscillatory zoning of trace element concentrations, with many crystals containing high U concentration cores that likely grew from highly evolved melt. The occurrence of distal Lava Creek tephra in stratigraphic sequences marking the Marine Isotope Stage 16–15 transition supports the apparent eruption age of ∼631 ka. The combined results reveal that Lava Creek zircons record episodic heating, renewed crystallization, and an overall up-temperature evolution for Yellowstone's subvolcanic reservoir in the 103−104 year interval before eruption.

  14. Exoplanet's Figure and Its Interior

    NASA Astrophysics Data System (ADS)

    Mian, Zhang; Cheng-li, Huang

    2018-01-01

    Along with the development of the observing technology, the observation and study on the exoplanets' oblateness and apsidal precession have achieved significant progress. The oblateness of an exoplanet is determined by its interior density profile and rotation period. Between its Love number k2 and core size exists obviously a negative correlation. So oblateness and k2 can well constrain its interior structure. Starting from the Lane-Emden equation, the planet models based on different polytropic indices are built. Then the flattening factors are obtained by solving the Wavre's integro-differential equation. The result shows that the smaller the polytropic index, the faster the rotation, and the larger the oblateness. We have selected 469 exoplanets, which have simultaneously the observed or estimated values of radius, mass, and orbit period from the NASA (National Aeronautics and Space Administration) Exoplanet Archive, and calculated their flattening factors under the two assumptions: tidal locking and fixed rotation period of 10.55 hours. The result shows that the flattening factors are too small to be detected under the tidal locking assumption, and that 28% of exoplanets have the flattening factors larger than 0.1 under the fixed rotation period of 10.55 hours. The Love numbers under the different polytropic models are solved by the Zharkov's approach, and the relation between k2 and core size is discussed.

  15. Transitions from near-surface to interior redox upon lithiation in conversion electrode materials.

    PubMed

    He, Kai; Xin, Huolin L; Zhao, Kejie; Yu, Xiqian; Nordlund, Dennis; Weng, Tsu-Chien; Li, Jing; Jiang, Yi; Cadigan, Christopher A; Richards, Ryan M; Doeff, Marca M; Yang, Xiao-Qing; Stach, Eric A; Li, Ju; Lin, Feng; Su, Dong

    2015-02-11

    Nanoparticle electrodes in lithium-ion batteries have both near-surface and interior contributions to their redox capacity, each with distinct rate capabilities. Using combined electron microscopy, synchrotron X-ray methods and ab initio calculations, we have investigated the lithiation pathways that occur in NiO electrodes. We find that the near-surface electroactive (Ni(2+) → Ni(0)) sites saturated very quickly, and then encounter unexpected difficulty in propagating the phase transition into the electrode (referred to as a "shrinking-core" mode). However, the interior capacity for Ni(2+) → Ni(0) can be accessed efficiently following the nucleation of lithiation "fingers" that propagate into the sample bulk, but only after a certain incubation time. Our microstructural observations of the transition from a slow shrinking-core mode to a faster lithiation finger mode corroborate with synchrotron characterization of large-format batteries and can be rationalized by stress effects on transport at high-rate discharge. The finite incubation time of the lithiation fingers sets the intrinsic limitation for the rate capability (and thus the power) of NiO for electrochemical energy storage devices. The present work unravels the link between the nanoscale reaction pathways and the C-rate-dependent capacity loss and provides guidance for the further design of battery materials that favors high C-rate charging.

  16. ExoMars Lander Radioscience LaRa, a Space Geodesy Experiment to Mars.

    NASA Astrophysics Data System (ADS)

    Dehant, Veronique; Le Maistre, Sebastien; Yseboodt, Marie; Peters, Marie-Julie; Karatekin, Ozgur; Van Hove, Bart; Rivoldini, Attilio; Baland, Rose-Marie; Van Hoolst, Tim

    2017-04-01

    The LaRa (Lander Radioscience) experiment is designed to obtain coherent two-way Doppler measurements from the radio link between the ExoMars lander and Earth over at least one Martian year. The instrument life time is thus almost twice the one Earth year of nominal mission duration. The Doppler measurements will be used to observe the orientation and rotation of Mars in space (precession, nutations, and length-of-day variations), as well as polar motion. The ultimate objective is to obtain information / constraints on the Martian interior, and on the sublimation / condensation cycle of atmospheric CO2. Rotational variations will allow us to constrain the moment of inertia of the entire planet, including its mantle and core, the moment of inertia of the core, and seasonal mass transfer between the atmosphere and the ice caps. The LaRa experiment will be combined with other ExoMars experiments, in order to retrieve a maximum amount of information on the interior of Mars. Specifically, combining LaRa's Doppler measurements with similar data from the Viking landers, Mars Pathfinder, Mars Exploration Rovers landers, and the forthcoming InSight-RISE lander missions, will allow us to improve our knowledge on the interior of Mars with unprecedented accuracy, hereby providing crucial information on the formation and evolution of the red planet.

  17. Surface-Enhanced Raman Scattering Active Plasmonic Nanoparticles with Ultrasmall Interior Nanogap for Multiplex Quantitative Detection and Cancer Cell Imaging.

    PubMed

    Li, Jiuxing; Zhu, Zhi; Zhu, Bingqing; Ma, Yanli; Lin, Bingqian; Liu, Rudi; Song, Yanling; Lin, Hui; Tu, Song; Yang, Chaoyong

    2016-08-02

    Due to its large enhancement effect, nanostructure-based surface-enhanced Raman scattering (SERS) technology had been widely applied for bioanalysis and cell imaging. However, most SERS nanostructures suffer from poor signal reproducibility, which hinders the application of SERS nanostructures in quantitative detection. We report an etching-assisted approach to synthesize SERS-active plasmonic nanoparticles with 1 nm interior nanogap for multiplex quantitative detection and cancer cell imaging. Raman dyes and methoxy poly(ethylene glycol) thiol (mPEG-SH) were attached to gold nanoparticles (AuNPs) to prepare gold cores. Next, Ag atoms were deposited on gold cores in the presence of Pluronic F127 to form a Ag shell. HAuCl4 was used to etch the Ag shell and form an interior nanogap in Au@AgAuNPs, leading to increased Raman intensity of dyes. SERS intensity distribution of Au@AgAuNPs was found to be more uniform than that of aggregated AuNPs. Finally, Au@AgAuNPs were used for multiplex quantitative detection and cancer cell imaging. With the advantages of simple and rapid preparation of Au@AgAuNPs with highly uniform, stable, and reproducible Raman intensity, the method reported here will widen the applications of SERS-active nanoparticles in diagnostics and imaging.

  18. Simulation of the planetary interior differentiation processes in the laboratory.

    PubMed

    Fei, Yingwei

    2013-11-15

    A planetary interior is under high-pressure and high-temperature conditions and it has a layered structure. There are two important processes that led to that layered structure, (1) percolation of liquid metal in a solid silicate matrix by planet differentiation, and (2) inner core crystallization by subsequent planet cooling. We conduct high-pressure and high-temperature experiments to simulate both processes in the laboratory. Formation of percolative planetary core depends on the efficiency of melt percolation, which is controlled by the dihedral (wetting) angle. The percolation simulation includes heating the sample at high pressure to a target temperature at which iron-sulfur alloy is molten while the silicate remains solid, and then determining the true dihedral angle to evaluate the style of liquid migration in a crystalline matrix by 3D visualization. The 3D volume rendering is achieved by slicing the recovered sample with a focused ion beam (FIB) and taking SEM image of each slice with a FIB/SEM crossbeam instrument. The second set of experiments is designed to understand the inner core crystallization and element distribution between the liquid outer core and solid inner core by determining the melting temperature and element partitioning at high pressure. The melting experiments are conducted in the multi-anvil apparatus up to 27 GPa and extended to higher pressure in the diamond-anvil cell with laser-heating. We have developed techniques to recover small heated samples by precision FIB milling and obtain high-resolution images of the laser-heated spot that show melting texture at high pressure. By analyzing the chemical compositions of the coexisting liquid and solid phases, we precisely determine the liquidus curve, providing necessary data to understand the inner core crystallization process.

  19. Simulation of the Planetary Interior Differentiation Processes in the Laboratory

    PubMed Central

    Fei, Yingwei

    2013-01-01

    A planetary interior is under high-pressure and high-temperature conditions and it has a layered structure. There are two important processes that led to that layered structure, (1) percolation of liquid metal in a solid silicate matrix by planet differentiation, and (2) inner core crystallization by subsequent planet cooling. We conduct high-pressure and high-temperature experiments to simulate both processes in the laboratory. Formation of percolative planetary core depends on the efficiency of melt percolation, which is controlled by the dihedral (wetting) angle. The percolation simulation includes heating the sample at high pressure to a target temperature at which iron-sulfur alloy is molten while the silicate remains solid, and then determining the true dihedral angle to evaluate the style of liquid migration in a crystalline matrix by 3D visualization. The 3D volume rendering is achieved by slicing the recovered sample with a focused ion beam (FIB) and taking SEM image of each slice with a FIB/SEM crossbeam instrument. The second set of experiments is designed to understand the inner core crystallization and element distribution between the liquid outer core and solid inner core by determining the melting temperature and element partitioning at high pressure. The melting experiments are conducted in the multi-anvil apparatus up to 27 GPa and extended to higher pressure in the diamond-anvil cell with laser-heating. We have developed techniques to recover small heated samples by precision FIB milling and obtain high-resolution images of the laser-heated spot that show melting texture at high pressure. By analyzing the chemical compositions of the coexisting liquid and solid phases, we precisely determine the liquidus curve, providing necessary data to understand the inner core crystallization process. PMID:24326245

  20. Discovering the interior of black holes

    NASA Astrophysics Data System (ADS)

    Brustein, Ram; Medved, A. J. M.; Yagi, K.

    2017-12-01

    The detection of gravitational waves (GWs) from black hole (BH) mergers provides an inroad toward probing the interior of astrophysical BHs. The general-relativistic description of the BH interior is that of empty spacetime with a (possibly) singular core. Recently, however, the hypothesis that the BH interior does not exist has been gaining traction, as it provides a means for resolving the BH information-loss problem. Here, we propose a simple method for answering the following question: Does the BH interior exist and, if so, does it contain some distribution of matter or is it mostly empty? Our proposal is premised on the idea that, similar to the case of relativistic, ultracompact stars, any BH-like object whose interior has some matter distribution should support fluid modes in addition to the conventional spacetime modes. In particular, the Coriolis-induced Rossby (r-) modes, whose spectrum is mostly insensitive to the composition of the interior matter, should be a universal feature of such BH-like objects. In fact, the frequency and damping time of these modes are determined by only the object's mass and speed of rotation. The r-modes oscillate at a lower frequency, decay at a slower rate, and produce weaker GWs than do the spacetime modes. Hence, they imprint a model-insensitive signature of a nonempty interior in the GW spectrum resulting from a BH merger. We find that future GW detectors, such as Advanced LIGO with its design sensitivity, have the potential of detecting such r-modes if the amount of GWs leaking out quantum mechanically from the interior of a BH-like object is sufficiently large.

  1. Role of volcanism in climate and evolution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Axelrod, D.I.

    1981-01-01

    Several major episodes of Tertiary explosive volcanism coincided with sharply lowered temperature as inferred from oxygen-isotope composition of foraminiferal tests in deep-sea cores. At these times, fossil floras in the western interior recorded significant changes. Reductions in taxa that required warmth occurred early in the Paleogene. Later, taxa that demand ample summer rain were reduced during a progressive change reflecting growth of the subtropic high. Other ecosystem changes that appear to have responded to volcanically induced climatic modifications include tachytely in Equidae (12 to 10 m.y. B.P.), rapid evolution of grasses (7 to 5 m.y. B.P.), evolution of marine mammals,more » and plankton flucuations. Although Lake Cretaceous extinctions commenced as epeiric seas retreated, the pulses of sharply lowered temperature induced by explosive volcanism, together with widespread falls of volcanic ash, may have led to extinction of dinosaurs, ammonites, cycadeoids, and other Cretaceous taxa. earlier, as Pangaea was assembled, Permian extinctions resulted not only from the elimination of oceans, epeiric seas, and shorelines, and the spread of more-continental climates, bu also from the climatic effects of major pulses of global volcanism and Gondwana glaciation.« less

  2. Synorogenic crustal fluid infiltration in the Idaho-Montana Thrust Belt

    NASA Astrophysics Data System (ADS)

    Bebout, Gray E.; Anastasio, David J.; Holl, James E.

    Mississippian carbonates in the Sevier thrust belt in Idaho-Montana show shifts in δ18OV-SMOW, from marine carbonate values to as low as +11‰, which are best explained by exchange with externally-derived, low-δ18O fluids. Late-stage, synkinematic calcite veins are depleted in 18O relative to the host-rocks and earlier-formed veins, many having δ18O of +5 to +10‰. These veins could have equilibrated with H2O with δ18O of -7.5 to +2.5‰, perhaps reflecting infiltration of the Sevier thrust wedge by nearshore meteoric waters to depths of ˜10 km. Calcite veins in the hangingwall and footwall of the Pioneer Metamorphic Core Complex, produced during later Paleogene extension, have δ18O of -8.7 to +1.4‰ consistent with equilibration with meteoric waters with δ18O as low as -14‰. Transition from a Cretaceous crustal fluid regime influenced by the nearby Western Interior Seaway to one influenced by lower-δ18O, more inland meteoric waters is consistent with seaway retreat during thrust wedge emergence and Paleogene uplift and subaerial volcanism.

  3. Last three millennia Earth's Magnetic field strength in Mesoamerica and southern United States: Implications in geomagnetism and archaeology

    NASA Astrophysics Data System (ADS)

    Goguitchaichvili, Avto; Ruiz, Rafael García; Pavón-Carrasco, F. Javier; Contreras, Juan Julio Morales; Arechalde, Ana María Soler; Urrutia-Fucugauchi, Jaime

    2018-06-01

    Earth's Magnetic Field variation strength may provide crucial information to understand the geodynamo mechanism and elucidate the conditions on the physics of the Earth's deep interiors. Aimed to reveal the fine characteristics of the geomagnetic field during the last three millennia in Mesoamerica, we analyzed the available absolute geomagnetic intensities associated to absolute radiometric dating as well some ages provided by historical documents. This analysis is achieved using thermoremanent magnetization carried by volcanic lava flows and burned archaeological artefacts. A total of 106 selected intensities from Mesoamerica and other 100 from the southern part of the United States represent the main core of the dataset to construct the variation curve using both combined bootstrap method and temporal penalized B-spline methods. The obtained intensity paleosecular variation curve for Mesoamerica generally disagrees with the values predicted by the global geomagnetic field models. There is rather firm evidence of eastward drift when compared to similar reference curves in Western Europe, Asia and Pacific Ocean. The recent hypothesis about the relationship between the geomagnetic field strength and paleoclimate is also critically analyzed in the light of this new data compilation.

  4. Technology Solutions Case Study: Durable Interior Foundation Insulation Retrofits for Cold Climates, Cloquet, Minnesota

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    Thermal and moisture problems in existing basements create a unique challenge as the exterior face of the wall is not easily or inexpensively accessible. This approach by the NorthernSTAR Building America Partnership team addresses thermal and moisture management from the interior face of the wall without disturbing the exterior soil and landscaping. It is effective at reducing energy loss through the wall principally during the heating season. The team conducted experiments at the Cloquet Residential Research Facility to test the heat and moisture performance of four hollow masonry block wall systems and two rim-joist systems. These systems were retrofitted withmore » interior insulation in compliance with the 2012 IECC. The research showed for the first time that, for masonry block walls in a cold climate, a solid bond beam or equivalent provides adequate resistance to moisture transport from a hollow core to the rim-joist cavity. Thus, a solid top course is a minimum requirement for an interior retrofit insulation system.« less

  5. Mechanical Properties of Degraded PMR-15 Resin

    NASA Technical Reports Server (NTRS)

    Tsuji, Luis C.

    2000-01-01

    Thermo-oxidative aging produces a nonuniform degradation state in PMR-15 resin. A surface layer, usually attributed to oxidative degradation, forms. This surface layer has different properties from the inner material. A set of material tests was designed to separate the properties of the oxidized surface layer from the properties of interior material. Test specimens were aged at 316 C in either air or nitrogen, for durations of up to 800 hr. The thickness of the oxidized surface layer in air aged specimens, and the shrinkage and coefficient of thermal expansion (CTE) of nitrogen aged specimens were measured directly. The nitrogen-aged specimens were assumed to have the same properties as the interior material in the air-aged specimens. Four-point-bend tests were performed to determine modulus of both the oxidized surface layer and the interior material. Bimaterial strip specimens consisting of oxidized surface material and unoxidized interior material were constructed and used to determine surface layer shrinkage and CTE. Results confirm that the surface layer and core materials have substantially different properties.

  6. METHOD AND APPARATUS FOR IMPROVING PERFORMANCE OF A FAST REACTOR

    DOEpatents

    Koch, L.J.

    1959-01-20

    A specific arrangement of the fertile material and fissionable material in the active portion of a fast reactor to achieve improvement in performance and to effectively lower the operating temperatures in the center of the reactor is described. According to this invention a group of fuel elements containing fissionable material are assembled to form a hollow fuel core. Elements containing a fertile material, such as depleted uranium, are inserted into the interior of the fuel core to form a central blanket. Additional elemenis of fertile material are arranged about the fuel core to form outer blankets which in tunn are surrounded by a reflector. This arrangement of fuel core and blankets results in substantial flattening of the flux pattern.

  7. Long-term climate patterns in Alaskan surface temperature and precipitation and their biological consequences

    USGS Publications Warehouse

    Simpson, James J.; Hufford, Gary L.; Fleming, Michael D.; Berg, Jared S.; Ashton, J.B.

    2002-01-01

    Mean monthly climate maps of Alaskan surface temperature and precipitation produced by the parameter-elevation regression on independent slopes model (PRISM) were analyzed. Alaska is divided into interior and coastal zones with consistent but different climatic variability separated by a transition region; it has maximum interannual variability but low long-term mean variability. Pacific decadal oscillation (PDO)- and El Nino Southern Oscillation (ENSO)-type events influence Alaska surface temperatures weakly (1-2/spl deg/C) statewide. PDO has a stronger influence than ENSO on precipitation but its influence is largely localized to coastal central Alaska. The strongest influence of Arctic oscillation (AO) occurs in northern and interior Alaskan precipitation. Four major ecosystems are defined. A major eco-transition zone occurs between the interior boreal forest and the coastal rainforest. Variability in insolation, surface temperature, precipitation, continentality, and seasonal changes in storm track direction explain the mapped ecosystems. Lack of westward expansion of the interior boreal forest into the western shrub tundra is influenced by the coastal marine boundary layer (enhanced cloud cover, reduced insolation, cooler surface and soil temperatures).

  8. Core Self-Evaluations, Worry, Life Satisfaction, and Psychological Well-Being: An Investigation in the Asian Context

    ERIC Educational Resources Information Center

    Rathi, Neerpal; Lee, Kidong

    2018-01-01

    The concept of core self-evaluations has been extensively investigated in Western and European countries, nonetheless its implications in Asian countries remains relatively unexplored. To void this gap, the current study investigated the association of core self-evaluations with worry, life satisfaction, and psychological well-being among South…

  9. EVALUATION OF THE DURABILITY OF THE STRUCTURAL CONCRETE OF REACTOR BUILDINGS AT SRS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Duncan, A.; Reigel, M.

    2011-02-28

    The Department of Energy (DOE) intends to close 100-150 facilities in the DOE complex using an in situ decommissioning (ISD) strategy that calls for grouting the below-grade interior volume of the structure and leaving the above-grade interior open or demolishing it and disposing of it in the slit trenches in E Area. These closures are expected to persist and remain stable for centuries, but there are neither facility-specific monitoring approaches nor studies on the rate of deterioration of the materials used in the original construction or on the ISD components added during closure (caps, sloped roofs, etc). This report willmore » focus on the evaluation of the actual aging/degradation of the materials of construction used in the ISD structures at Savannah River Site (SRS) above grade, specifically P & R reactor buildings. Concrete blocks (six 2 to 5 ton blocks) removed from the outer wall of the P Reactor Building were turned over to SRNL as the first source for concrete cores. Larger cores were received as a result of grouting activities in P and R reactor facilities. The cores were sectioned and evaluated using microscopy, x-ray diffraction (XRD), ion chromatography (IC) and thermal analysis. Scanning electron microscopy shows that the aggregate and cement phases present in the concrete are consistent with the mix design and no degradation mechanisms are evident at the aggregate-cement interfaces. Samples of the cores were digested and analyzed for chloride ingress as well as sulfate attack. The concentrations of chloride and sulfate ions did not exceed the limits of the mix design and there is no indication of any degradation due to these mechanisms. Thermal analysis on samples taken along the longitudinal axis of the cores show that there is a 1 inch carbonation layer (i.e., no portlandite) present in the interior wall of the reactor building and a negligible carbonation layer in the exterior wall. A mixed layer of carbonate and portlandite extends deeper into the interior (2-3 inches) and exterior (1-2 inches) walls. This is more extensive than measured in previous SRS structures. Once the completely carbonated layer reaches the rebar that is approximately 2-3 inches into the concrete wall, the steel is susceptible to corrosion. The growth rate of the carbonated layer was estimated from current observations and previous studies. Based on the estimated carbonation rate, the steel rebar should be protected from carbonation induced corrosion for at least another 100 years. If degradation of these structures is dominated by the carbonation mechanism, the length of time before water intrusion is expected into the process room of P-reactor is estimated to be between 425-675 years.« less

  10. Role of selection and gene flow in population differentiation at the edge vs. interior of the species range differing in climatic conditions.

    PubMed

    Volis, S; Ormanbekova, D; Shulgina, I

    2016-04-01

    Evaluating the relative importance of neutral and adaptive processes as determinants of population differentiation across environments is a central theme of evolutionary biology. We applied the QST-FST comparison flanked by a direct test for local adaptation to infer the role of climate-driven selection and gene flow in population differentiation of an annual grass Avena sterilis in two distinct parts of the species range, edge and interior, which represent two globally different climates, desert and Mediterranean. In a multiyear reciprocal transplant experiment, the plants of desert and Mediterranean origin demonstrated home advantage, and population differentiation in several phenotypic traits related to reproduction exceeded neutral predictions, as determined by comparisons of QST values with theoretical FST distributions. Thus, variation in these traits likely resulted from local adaptation to desert and Mediterranean environments. The two separate common garden experiments conducted with different experimental design revealed that two population comparisons, in contrast to multi-population comparisons, are likely to detect population differences in virtually every trait, but many of these differences reflect effects of local rather than regional environment. We detected a general reduction in neutral (SSR) genetic variation but not in adaptive quantitative trait variation in peripheral desert as compared with Mediterranean core populations. On the other hand, the molecular data indicated intensive gene flow from the Mediterranean core towards desert periphery. Although species range position in our study (edge vs. interior) was confounded with climate (desert vs. Mediterranean), the results suggest that the gene flow from the species core does not have negative consequences for either performance of the peripheral plants or their adaptive potential. © 2016 John Wiley & Sons Ltd.

  11. Geophysical Investigations of Habitability in Ice-Covered Ocean Worlds

    NASA Astrophysics Data System (ADS)

    Vance, Steven D.; Panning, Mark P.; Stähler, Simon; Cammarano, Fabio; Bills, Bruce G.; Tobie, Gabriel; Kamata, Shunichi; Kedar, Sharon; Sotin, Christophe; Pike, William T.; Lorenz, Ralph; Huang, Hsin-Hua; Jackson, Jennifer M.; Banerdt, Bruce

    2018-01-01

    Geophysical measurements can reveal the structures and thermal states of icy ocean worlds. The interior density, temperature, sound speed, and electrical conductivity thus characterize their habitability. We explore the variability and correlation of these parameters using 1-D internal structure models. We invoke thermodynamic consistency using available thermodynamics of aqueous MgSO4, NaCl (as seawater), and NH3; pure water ice phases I, II, III, V, and VI; silicates; and any metallic core that may be present. Model results suggest, for Europa, that combinations of geophysical parameters might be used to distinguish an oxidized ocean dominated by MgSO4 from a more reduced ocean dominated by NaCl. In contrast with Jupiter's icy ocean moons, Titan and Enceladus have low-density rocky interiors, with minimal or no metallic core. The low-density rocky core of Enceladus may comprise hydrated minerals or anhydrous minerals with high porosity. Cassini gravity data for Titan indicate a high tidal potential Love number (k2>0.6), which requires a dense internal ocean (ρocean>1,200 kg m-3) and icy lithosphere thinner than 100 km. In that case, Titan may have little or no high-pressure ice, or a surprisingly deep water-rock interface more than 500 km below the surface, covered only by ice VI. Ganymede's water-rock interface is the deepest among known ocean worlds, at around 800 km. Its ocean may contain multiple phases of high-pressure ice, which will become buoyant if the ocean is sufficiently salty. Callisto's interior structure may be intermediate to those of Titan and Europa, with a water-rock interface 250 km below the surface covered by ice V but not ice VI.

  12. Fluid core size of Mars from detection of the solar tide

    NASA Technical Reports Server (NTRS)

    Yoder, C. F.; Konopliv, A. S.; Yuan, D. N.; Standish, E. M.; Folkner, W. M.

    2003-01-01

    The solar tidal deformation of Mars, measured by its k2 potential Love number, has been obtained from an analysis of Mars Global Surveyor radio tracking. The observed k2 of 0.153 +/- 0.017 is large enough to rule out a solid iron core and so indicates that at least the outer part of the core is liquid. The inferred core radius is between 1520 and 1840 kilometers and is independent of many interior properties, although partial melt of the mantle is one factor that could reduce core size. Ice-cap mass changes can be deduced from the seasonal variations in air pressure and the odd gravity harmonic J3, given knowledge of cap mass distribution with latitude. The south cap seasonal mass change is about 30 to 40% larger than that of the north cap.

  13. Fluid Core Size of Mars from Detection of the Solar Tide

    NASA Astrophysics Data System (ADS)

    Yoder, C. F.; Konopliv, A. S.; Yuan, D. N.; Standish, E. M.; Folkner, W. M.

    2003-04-01

    The solar tidal deformation of Mars, measured by its k2 potential Love number, has been obtained from an analysis of Mars Global Surveyor radio tracking. The observed k2 of 0.153 +/- 0.017 is large enough to rule out a solid iron core and so indicates that at least the outer part of the core is liquid. The inferred core radius is between 1520 and 1840 kilometers and is independent of many interior properties, although partial melt of the mantle is one factor that could reduce core size. Ice-cap mass changes can be deduced from the seasonal variations in air pressure and the odd gravity harmonic J3, given knowledge of cap mass distribution with latitude. The south cap seasonal mass change is about 30 to 40% larger than that of the north cap.

  14. Core/corona modeling of diode-imploded annular loads

    NASA Astrophysics Data System (ADS)

    Terry, R. E.; Guillory, J. U.

    1980-11-01

    The effects of a tenuous exterior plasma corona with anomalous resistivity on the compression and heating of a hollow, collisional aluminum z-pinch plasma are predicted by a one-dimensional code. As the interior ("core") plasma is imploded by its axial current, the energy exchange between core and corona determines the current partition. Under the conditions of rapid core heating and compression, the increase in coronal current provides a trade-off between radial acceleration and compression, which reduces the implosion forces and softens the pitch. Combined with a heuristic account of energy and momentum transport in the strongly coupled core plasma and an approximate radiative loss calculation including Al line, recombination and Bremsstrahlung emission, the current model can provide a reasonably accurate description of imploding annular plasma loads that remain azimuthally symmetric. The implications for optimization of generator load coupling are examined.

  15. A Year of Progress: Preparing for the 21st Century.

    ERIC Educational Resources Information Center

    Department of the Interior, Washington, DC.

    Achievements of the Department of Interior for 1981 in the areas of natural resources, parks, wildlife areas, water, Western lands, Indian reservations, and island territories are reported. Section 1 outlines increases in onshore and offshore oil and gas, coal, and geothermal leases on federal lands. Section 2 describes results in the change of…

  16. The B. C. Central Interior. Horizon Reprint.

    ERIC Educational Resources Information Center

    Moles, Garvin, Ed.; Thomas, Paul F. Ed.

    1986-01-01

    This set of materials meets the need created by the new social studies curriculum which requires teaching emphasis on British Columbia and Western Canada. The document includes a presentation of the geography of the Mackenzie Grease Trail, New Caledonia, and Prince George; examines some aspects of the history of the region; and discusses the most…

  17. Nitrogen mineralization in the aspen ecosystem

    Treesearch

    M. C. Amacher; A. D. Johnson; T. Christopherson; D. E. Kutterer; D. L. Bartos; J. Kotuby-Amacher

    1999-01-01

    Aspen (Populus tremuloides) are in decline throughout the interior western U.S. because of conifer invasion, fire suppression, and overbrowsing by domestic livestock and native ungulates. Aspen restoration requires disturbances such as fire or cutting and exclosures to protect against overbrowsing. We measured the effects of the 1996 Pole Creek fire, Fishlake NF, UT on...

  18. 75 FR 30852 - Hydroelectric Power Development at Ridgway Dam, Dallas Creek Project, Colorado

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-02

    ... Gold, Assistant Regional Director, Upper Colorado Region. [FR Doc. 2010-13149 Filed 6-1-10; 8:45 am..., Dallas Creek Project, Colorado AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of intent to..., Area Manager, Western Colorado Area Office, Bureau of Reclamation, 2764 Compass Drive, Suite 106, Grand...

  19. 77 FR 9696 - Notice of Proposed Reinstatement of Terminated Oil and Gas Lease COC68134

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-17

    ...] Notice of Proposed Reinstatement of Terminated Oil and Gas Lease COC68134 AGENCY: Bureau of Land Management, Interior. ACTION: Notice of Proposed Reinstatement of Terminated Oil and Gas Lease. SUMMARY... Management (BLM) received a petition for reinstatement of oil and gas lease COC68134 from Western Operation...

  20. Decline of quaking aspen in the Interior West - examples from Utah

    Treesearch

    Dale L. Bartos; Robert B. Campbell

    1998-01-01

    Quaking aspen (Populus tremuloides) are unique because, in contrast to most western forest trees, they reproduce primarily by suckering from the parent root system. Generally disturbance or dieback is necessary to stimulate regeneration of aspen stands. These self-regenerating stands have existed for thousands of years. If they are lost from the...

  1. Demography of northern flying squirrels informs ecosystem management of western interior forests.

    Treesearch

    John F. Lehmkuhl; Keith D. Kistler; James S. Begley; John. Boulanger

    2006-01-01

    We studied northern flying squirrel (Glaucomys sabrinus) demography in the eastern Washington Cascade Range to test hypotheses about regional and local abundance patterns and to inform managers of the possible effects of fire and fuels management on flying squirrels. We quantified habitat characteristics and squirrel density, population trends, and...

  2. Cercocarpus Kunth: mountain-mahogany

    Treesearch

    Stanley G. Kitchen

    2008-01-01

    The mountain mahoganies - genus Cercocarpus - are 8 to 10 species of moderately to intricately branched shrubs or small trees that are endemic to dry coastal and interior mountains of the western United States and Mexico (Stutz 1990). Leaves are generally persistent and stems are unarmed. Two of the most widely distributed and utilized species are described here.

  3. Chapter 8: Simulating mortality from forest insects and diseases

    Treesearch

    Alan A. Ager; Jane L. Hayes; Craig L. Schmitt

    2004-01-01

    We describe methods for incorporating the effects of insects and diseases on coniferous forests into forest simulation models and discuss options for including this capability in the modeling work of the Interior Northwest Landscape Analysis System (INLAS) project. Insects and diseases are major disturbance agents in forested ecosystems in the Western United States,...

  4. 77 FR 68147 - Gulf of Mexico, Outer Continental Shelf (OCS), Western Planning Area (WPA), Oil and Gas Lease...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-15

    ... Environmental Impact Statement (Multisale FEIS). Authority: This NOA is published pursuant to the regulations... NEPA process. The Multisale FEIS evaluated the environmental and socioeconomic impacts for WPA Lease... DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management Gulf of Mexico, Outer Continental...

  5. Wyoming big sagebrush: Efforts towards development of target plants for restoration

    Treesearch

    Kayla R. Herriman

    2009-01-01

    Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis) is a dominant shrub throughout much of the interior western United States. It is a key component of sagebrush steppe ecosystems, which have been degraded due to European settlement, improper land use, and changing fire regimes resulting from the invasion of exotic...

  6. Small-diameter trees used for chemithermomechanical pulps.

    Treesearch

    Gary C. Myers; R. James Barbour; Said M. Abubakr

    1999-01-01

    During the course of restoring and maintaining forest ecosystem health and function in the western interior of the United States, many small-diameter stems are removed from densely stocked stands. In general, these materials are considered nonusable or underutilized. Information on the properties of these resources is needed to help managers understand when timber...

  7. Artemisia L.: sagebrush

    Treesearch

    Susan E. Meyer

    2008-01-01

    Sagebrush - Artemisia L. - species are probably the most common shrubs in western North America. Big sagebrush alone occupies an estimated 60 million ha as a landscape dominant or codominant in the semiarid interior, and related species of the subgenus Tridentatae are estimated to occupy an additional 50 million ha (Beetle 1960; McArthur and Stevens in press)....

  8. 77 FR 27533 - Application for Presidential Permit To Construct, Operate and Maintain Pipeline Facilities on the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-10

    ... pipeline that is designed to transport crude oil produced in the Western Canadian Sedimentary Basin (WCSB) and from other sources to a terminus in Steele City, Nebraska where it is designed to link with an... Order 13337: The Departments of Energy, Defense, Transportation, Homeland Security, Justice, Interior...

  9. Canada: A Regionally Diverse and Northern Environment. Understanding the Canadian Environment.

    ERIC Educational Resources Information Center

    Brown, Rex B.; And Others

    One of a series of student booklets on the Canadian environment, this unit presents Canada from a geomorphological perspective of the six major regions: the Western Cordillera, the Interior Plains, the Canadian Shield, the Far North, the Great Lakes-St. Lawrence Lowlands, and Appalachian Canada. Intended to help secondary students understand the…

  10. Creosotebush, blackbrush, and interior chaparral shrublands [Chapter 6

    Treesearch

    Matthew L. Brooks; Todd C. Esque; Tim Duck

    2007-01-01

    The vegetation, fire regime, and Fire Regime Condition Class descriptions in this paper apply broadly to the Mojave Desert, Colorado Plateau, and southern Great Basin of western North America. More detail on these topics, including estimated percentages within each condition class, is provided for the Mojave-Colorado Plateau ecotone spanning southern Nevada, the...

  11. Ecological genetics of floret mass variation in Bromus tectorum (Poaceae)

    Treesearch

    Susan E. Meyer

    2010-01-01

    Bromus tectorum L. (cheatgrass, downy brome) is a highly invasive inbreeding annual grass that dominates millions of hectares of former shrubland in interior western North America. Factors contributing to its success include strong genetic regulation of key adaptive traits coupled with high phenotypic plasticity in response to resource availability (Meyer and Allen...

  12. Characterizing crown fuel distribution for conifers in the interior western United States

    Treesearch

    Seth Ex; Frederick W. Smith; Tara Keyser

    2015-01-01

    Canopy fire hazard evaluation is essential for prioritizing fuel treatments and for assessing potential risk to firefighters during suppression activities. Fire hazard is usually expressed as predicted potential fire behavior, which is sensitive to the methodology used to quantitatively describe fuel profiles: methodologies that assume that fuel is distributed...

  13. Contribution of actinorhizal shrubs to site fertility in a northern California mixed pine forest

    Treesearch

    Matt D. Busse; Martin F. Jurgensen; Deborah S. Page-Dumroese; Robert F. Powers

    2007-01-01

    Bitterbrush (Purshia tridentata) and mahala mat (Ceanothus prostratus) are common N-fixing shrubs in interior forests of the western United States, yet their contribution to ecosystem N pools is poorly characterized. We compared N fixation and soil N accretion by these shrubs in old-growth ponderosa pine (Pinus ponderosa...

  14. First-year postfire and postharvest soil temperatures in aspen and conifer stands

    Treesearch

    Michael C. Amacher; Amber D. Johnson; Debra E. Kutterer; Dale L. Bartos

    2001-01-01

    Aspen (Populus tremuloides Michx.) stands are in decline throughout the Interior Western United States because of fire suppression, overbrowsing by domestic livestock and native ungulates, and forest succession. We measured summertime soil temperatures in stable aspen, decadent aspen, and mixed aspen/conifer stands; a mixed aspen/conifer clearcut;...

  15. Iron-sulfur-carbon relationships in organic-carbon-rich sequences I: Cretaceous Western Interior seaway

    USGS Publications Warehouse

    Dean, W.E.; Arthur, M.A.

    1989-01-01

    Cretaceous marine strata deposited in shallow to intermediate depths in the Western Interior seaway of North America show considerable variation in organic-carbon enrichment and degree of pyrite formation. The extreme range of paleoceanographic and depositional conditions that occurred in this seaway provide a unique opportunity to examine the effects of iron-, carbon-, and sulfur-limitation on pyrite formation in one region over about 30 my. Ternary diagrams of the system Fe-S-OC, together with some measure of the reactivity of organic matter (pyrolysis hydrogen index), provide a rapid means of recognizing iron-, carbon-, and sulfur-limitation on pyrite formation in a series of samples from a single lithologic unit. Iron limitation is indicated by a concentration of data along a line of constant S/Fe ratio on a Fe-S-OC ternary diagram. Carbon limitation is indicated by a concentration of data along a line of constant S/OC ratio. Sulfur-limitation is suggested by the lack of a systematic Fe-S-OC relationship and residual organic matter that is high in abundance and reactivity. -from Authors

  16. Western Tropical Atlantic Hydrologic change during the last 130,000 years

    NASA Astrophysics Data System (ADS)

    McGrath, S. M.; Lavoie, N.; Oppo, D.

    2016-12-01

    Abrupt climate changes in the North Atlantic during the last 130,000 years are associated with hydrologic changes in the western tropical Atlantic Ocean. Previous studies on marine sediment cores from between 4°S and the equator have documented pulses of terrigenous sediment recording increased precipitation and weathering on the Brazilian Nordeste associated with Heinrich events. We worked on cores KNR197-3-11CDH (7°40'N, 53°49'W, water depth 550 m) and KNR 197-3-46CDH (7°50.1621'N, 53°39.8051'W, 947m water depth) located farther north along the South American continental slope, where sediment derives from the Amazon river basin and is transported by the North Brazilian Current. Preliminary stratigraphy based on magnetic susceptibility shows a possible correlation with the Greenland ice core δ18O stratigraphy. We use sediment elemental composition, determined by x-ray fluorescence (XRF) to evaluate variations in terrigenous sediment runoff and δ18O of the planktonic foraminifers Globierinoides ruber to evaluate variations in western tropical North Atlantic surface hydrography across North Atlantic abrupt climate events. Similarities and differences among our records and the records from the more southerly cores will help understand the mechanisms of hydrologic changes in the regions on abrupt climate time scales.

  17. Interior structure and seasonal mass redistribution of Mars from radio tracking of Mars Pathfinder

    NASA Technical Reports Server (NTRS)

    Folkner, W. M.; Yoder, C. F.; Yuan, D. N.; Standish, E. M.; Preston, R. A.

    1997-01-01

    Doppler and range measurements to the Mars Pathfinder lander made using its radio communications system have been combined with similar measurements from the Viking landers to estimate improved values of the precession of Mars' pole of rotation and the variation in Mars' rotation rate. The observed precession of -7576 +/- 35 milliarc seconds of angle per year implies a dense core and constrains possible models of interior composition. The estimated annual variation in rotation is in good agreement with a model of seasonal mass exchange of carbon dioxide between the atmosphere and ice caps.

  18. GRAIL Mission Briefing

    NASA Image and Video Library

    2011-08-25

    Maria Zuber, GRAIL principal investigator, Massachusetts Institute of Technology, Cambridge, answers a reporter's question at a press briefing about the upcoming launch to the moon of the Gravity Recovery and Interior Laboratory (GRAIL) mission, Thursday, Aug. 25, 2011 in Washington. GRAIL's primary science objectives are to determine the structure of the lunar interior, from crust to core, and to advance understanding of the thermal evolution of the moon. The mission will place two spacecraft into the same orbit around the moon which will gather information about the its gravitational field enabling scientists to create a high-resolution map. Photo Credit: (NASA/Carla Cioffi)

  19. Interior structure and seasonal mass redistribution of Mars from radio tracking of Mars Pathfinder.

    PubMed

    Folkner, W M; Yoder, C F; Yuan, D N; Standish, E M; Preston, R A

    1997-12-05

    Doppler and range measurements to the Mars Pathfinder lander made using its radio communications system have been combined with similar measurements from the Viking landers to estimate improved values of the precession of Mars' pole of rotation and the variation in Mars' rotation rate. The observed precession of -7576 +/- 35 milliarc seconds of angle per year implies a dense core and constrains possible models of interior composition. The estimated annual variation in rotation is in good agreement with a model of seasonal mass exchange of carbon dioxide between the atmosphere and ice caps.

  20. GRAIL Mission Briefing

    NASA Image and Video Library

    2011-08-25

    David Lehman, GRAIL project manager, NASA's Jet Propulsion Laboratory, Pasadena, Calif., speaks at a press conference about the upcoming launch to the moon of the Gravity Recovery and Interior Laboratory (GRAIL) mission, Thursday, Aug. 25, 2011 in Washington. GRAIL's primary science objectives are to determine the structure of the lunar interior, from crust to core, and to advance understanding of the thermal evolution of the moon. The mission will place two spacecraft into the same orbit around the moon which will gather information about the its gravitational field enabling scientists to create a high-resolution map. Photo Credit: (NASA/Carla Cioffi)

  1. Global and Local Gravity Field Models of the Moon Using GRAIL Primary and Extended Mission Data

    NASA Technical Reports Server (NTRS)

    Goossens, Sander; Lemoine, Frank G.; Sabaka, Terence J.; Nicholas, Joseph B.; Mazarico, Erwan; Rowlands, David D.; Loomis, Bryant D.; Chinn, Douglas S.; Neumann, Gregory A.; Smith, David E.; hide

    2015-01-01

    The Gravity Recovery and Interior Laboratory (GRAIL) mission was designed to map the structure of the lunar interior from crust to core and to advance the understanding of the Moon's thermal evolution by producing a high-quality, high-resolution map of the gravitational field of the Moon. The mission consisted of two spacecraft, which were launched in September 2011 on a Discovery-class NASA mission. Ka-band tracking between the two satellites was the single science instrument, augmented by tracking from Earth using the Deep Space Network (DSN).

  2. Fluvial-deltaic sedimentation and stratigraphy of the ferron sandstone

    USGS Publications Warehouse

    Anderson, P.B.; Chidsey, T.C.; Ryer, T.A.

    1997-01-01

    East-central Utah has world-class outcrops of dominantly fluvial-deltaic Turonian to Coniacian aged strata deposited in the Cretaceous foreland basin. The Ferron Sandstone Member of the Mancos Shale records the influences of both tidal and wave energy on fluvial-dominated deltas on the western margin of the Cretaceous western interior seaway. Revisions of the stratigraphy are proposed for the Ferron Sandstone. Facies representing a variety of environments of deposition are well exposed, including delta-front, strandline, marginal marine, and coastal-plain. Some of these facies are described in detail for use in petroleum reservoir characterization and include permeability structure.

  3. Resolving mantle structure beneath the Pacific Northwest

    NASA Astrophysics Data System (ADS)

    Darold, A. P.; Humphreys, E.; Schmandt, B.; Gao, H.

    2011-12-01

    Cenozoic tectonics of the Pacific Northwest (PNW) and the associated mantle structures are remarkable, the latter revealed only recently by EarthScope seismic data. Over the last ~66 Ma this region experienced a wide range of tectonic and magmatic conditions: Laramide compression, ~75-53 Ma, involving Farallon flat-slab subduction, regional uplift, and magmatic quiescence. With the ~53 Ma accretion of Siletzia ocean lithosphere within the Columbia Embayment, westward migration of subduction beginning Cascadia, along with initiation of the Cascade volcanic arc. Within the continental interior the Laramide orogeny was quickly followed by a period of extension involving metamorphic core complexes and the associated initial ignimbrite flare-up (both in northern Washington, Idaho, and western Montana); interior magmo-tectonic activity is attributed to flat-slab removal and (to the south) slab rollback. Rotation of Siletzia created new crust on SE Oregon and, at ~16 Ma, the Columbia River Flood Basalt (CRB) eruptions renewed vigorous magmatism. We have united several EarthScope studies in the Pacific Northwest and have focused on better resolving the major mantle structures that have been discovered. We have tomographically modeled the body waves with teleseismic, finite-frequency code under the constraints of ambient noise tomography and teleseismic receiver function models of Gao et al. (2011), and teleseismic anisotropy models of Long et al. (2009) in order to resolve structures continuously from the surface to the base of the upper mantle. We now have clear imaging of two episodes of subduction: Juan De Fuca slab deeper than ~250 km is absent across much of the PNW, and it has an E-W tear located beneath northern Oregon; Farallon slab (the "Siletzia curtain") is still present, hanging vertically just inboard of the core complexes, and with a basal tear causing the structure to extend deeper (~600 km) beneath north-central Idaho than beneath south-central Idaho and northern Washington (~300 km). Lying just west of the Siletzia curtain, beneath NE Oregon, is a prominent high-velocity body centered on 250 km depth. Its nearly circular plan view corresponds with the area of intense Columbia River Basalt eruptions and with the circular topographic bull's eye centered on the recently uplifted (post CRB) Wallowa Mountains. Finally, we are investigating a very low-velocity volume of mantle present between the E-W Juan de Fuca tear and the high-velocity body beneath the Wallowa Mountains. At 250 km depth this is the strongest low-velocity anomaly beneath the western U.S. Presently we are completing resolution testing on the structures revealed through our imaging in order to resolve their structural details. These synthetic resolution tests along with the high resolution imaging of the crust and upper mantle will clarify several previously cited structures as well as strengthen our conclusions on the tectonic history and geodynamical evolution of the mantle while aiding in putting together a comprehensive story for the area.

  4. Internal structure of the Moon inferred from Apollo seismic data and selenodetic data from GRAIL and LLR

    NASA Astrophysics Data System (ADS)

    Matsumoto, Koji; Yamada, Ryuhei; Kikuchi, Fuyuhiko; Kamata, Shunichi; Ishihara, Yoshiaki; Iwata, Takahiro; Hanada, Hideo; Sasaki, Sho

    2015-09-01

    The internal structure of the Moon is important for discussions on its origin and evolution. However, the deep structure of the Moon is still debated due to the absence of comprehensive seismic data. This study explores lunar interior models by complementing Apollo seismic travel time data with selenodetic data which have recently been improved by Gravity Recovery and Interior Laboratory (GRAIL) and Lunar Laser Ranging (LLR). The observed data can be explained by models including a deep-seated zone with a low velocity (S wave velocity = 2.9 ± 0.5 km/s) and a low viscosity (˜3 × 1016 Pa s). The thickness of this zone above the core-mantle boundary is larger than 170 km, showing a negative correlation with the radius of the fluid outer core. The inferred density of the lowermost mantle suggests a high TiO2 content (>11 wt.%) which prefers a mantle overturn scenario.

  5. Safety apparatus for nuclear reactor to prevent structural damage from overheating by core debris

    DOEpatents

    Gabor, John D.; Cassulo, John C.; Pedersen, Dean R.; Baker, Jr., Louis

    1986-01-01

    The invention teaches safety apparatus that can be included in a nuclear reactor, either when newly fabricated or as a retrofit add-on, that will minimize proliferation of structural damage to the reactor in the event the reactor is experiencing an overheating malfunction whereby radioactive nuclear debris might break away from and be discharged from the reactor core. The invention provides a porous bed or sublayer on the lower surface of the reactor containment vessel so that the debris falls on and piles up on the bed. Vapor release elements upstand from the bed in some laterally spaced array. Thus should the high heat flux of the debris interior vaporize the coolant at that location, the vaporized coolant can be vented downwardly to and laterally through the bed to the vapor release elements and in turn via the release elements upwardly through the debris. This minimizes the pressure buildup in the debris and allows for continuing infiltration of the liquid coolant into the debris interior.

  6. Safety apparatus for nuclear reactor to prevent structural damage from overheating by core debris

    DOEpatents

    Gabor, John D.; Cassulo, John C.; Pedersen, Dean R.; Baker Jr., Louis

    1986-07-01

    The invention teaches safety apparatus that can be included in a nuclear reactor, either when newly fabricated or as a retrofit add-on, that will minimize proliferation of structural damage to the reactor in the event the reactor is experiencing an overheating malfunction whereby radioactive nuclear debris might break away from and be discharged from the reactor core. The invention provides a porous bed or sublayer on the lower surface of the reactor containment vessel so that the debris falls on and piles up on the bed. Vapor release elements upstand from the bed in some laterally spaced array. Thus should the high heat flux of the debris interior vaporize the coolant at that location, the vaporized coolant can be vented downwardly to and laterally through the bed to the vapor release elements and in turn via the release elements upwardly through the debris. This minimizes the pressure buildup in the debris and allows for continuing infiltration of the liquid coolant into the debris interior.

  7. Evaluation of Iron Loss in Interior Permanent Magnet Synchronous Motor with Consideration of Rotational Field

    NASA Astrophysics Data System (ADS)

    Ma, Lei; Sanada, Masayuki; Morimoto, Shigeo; Takeda, Yoji; Kaido, Chikara; Wakisaka, Takeaki

    Loss evaluation is an important issue in the design of electrical machines. Due to the complicate structure and flux distribution, it is difficult to predict the iron loss in the machines exactly. This paper studies the iron loss in interior permanent magnet synchronous motors based on the finite element method. The iron loss test data of core material are used in the fitting of the hysteresis and eddy current loss constants. For motors in practical operation, additional iron losses due to the appearance of rotation of flux density vector and harmonic flux density distribution makes the calculation data deviates from the measured ones. Revision is made to account for these excess iron losses which exist in the practical operating condition. Calculation results show good consistence with the experimental ones. The proposed method provides a possible way to predict the iron loss of the electrical machine with good precision, and may be helpful in the selection of the core material which is best suitable for a certain machine.

  8. Safety apparatus for nuclear reactor to prevent structural damage from overheating by core debris

    DOEpatents

    Gabor, J.D.; Cassulo, J.C.; Pedersen, D.R.; Baker, L. Jr.

    The invention teaches safety apparatus that can be included in a nuclear reactor, either when newly fabricated or as a retrofit add-on, that will minimize proliferation of structural damage to the reactor in the event the reactor is experiencing an overheating malfunction whereby radioactive nuclear debris might break away from and can be discharged from the reactor core. The invention provides a porous bed of sublayer on the lower surface of the reactor containment vessel so that the debris falls on and piles up on the bed. Vapor release elements upstand from the bed in some laterally spaced array. Thus should the high heat flux of the debris interior vaporize the coolant at that location, the vaporized coolant can be vented downwardly to and laterally through the bed to the vapor release elements and in turn via the release elements upwardly through the debris. This minimizes the pressure buildup in the debris and allows for continuing infiltration of the liquid coolant into the debris interior.

  9. Core formation, wet early mantle, and H2O degassing on early Mars

    NASA Technical Reports Server (NTRS)

    Kuramoto, K.; Matsui, T.

    1993-01-01

    Geophysical and geochemical observations strongly suggest a 'hot origin of Mars,' i.e., the early formation of both the core and the crust-mantle system either during or just after planetary accretion. To consider the behavior of H2O in the planetary interior it is specifically important to determine by what mechanism the planet is heated enough to cause melting. For Mars, the main heat source is probably accretional heating. Because Mars is small, the accretion energy needs to be effectively retained in its interior. Therefore, the three candidates of heat retention mechanism are discussed first: (1) the blanketing effect of the primordial H2-He atmosphere; (2) the blanketing effect of the impact-induced H2O-CO2 atmosphere; and (3) the higher deposition efficiency of impact energy due to larger impacts. It was concluded that (3) the is the most plausible mechanism for Mars. Then, its possible consequence on how wet the early martian mantle was is discussed.

  10. Atmosphere aerosol/dust composition over central Asia and western Siberia derived from snow/ice core records and calibrated with NASA remote sensing data

    NASA Astrophysics Data System (ADS)

    Aizen, V. B.; Aizen, E. M.; Joswiak, D. R.; Surazakov, A. B.; Takeuchi, N.

    2007-12-01

    The vast arid and semi-arid regions of central Asia, Mongolia, and Northern China are the world's second largest source of atmospheric mineral dust. In recent years, severe dust storms in Asia have intensified in frequency, duration, and areal coverage. However, limited spatial and temporal extent of aerosol measurements precludes definitive statements to be made regarding relationship between the Asian aerosol generation and climate. It has been well known that glaciers are the natural archives of environmental records related to past climate and aerosol generation. In our research, we utilized central Asian and western Siberia shallow ice-core records recovered from Altai, Tien Shan and Pamir mountain glaciers. Despite the fact that ice-core data may extend climate/aerosol records back in time, their sparse coverage is inadequate to document aerosol spatial distribution. The NASA products from Aura, Terra and Aqua satellite missions address this gap identifying aerosol sources, transport pathways, and area of deposition. The main objective of our research is to evaluate an affect of climate variability on dynamics of Asian aerosol loading to atmosphere and changes in aerosol transport pathways. Dust particle, major and rare earth element analysis from dust aerosols deposited and accumulated in Altai, Tien Shan and Pamir glaciers suggests that loess from Tajikistan, Afghanistan and north-western China are main sources of aerosol loading into the upper troposphere over the central Asia and western Siberia. At the same time, the soluble ionic component of the ice-cores, related to aerosol generated from evaporate deposits, demonstrated both anthropogenic and natural impacts on atmospheric chemistry over these regions. Large perturbations of Ca2+ derived from CaCO3- rich dust transported from Goby Desert to Altai and Tien Shan. Origin and pathway of the ice-core aerosol depositions for the last 10-years were identified through calibrating ice-core records with dust storm land surface records and remote sensing aerosol data at the monthly/seasonal/annual to event/daily scale. For instance, in southwestern Asia, severe drought developed from 1998 to 2002 has intensified the frequency, duration, and spatial coverage of large dust storms originated in Iran, Afghanistan, Tajikistan, Taklimakan and Goby Deserts. The Pamir and Tien Shan ice-core records revealed, that concentration of major and REE elements during summer is about two times greater in period of 1998-2002 than at the following years. Our qualitative analysis based on ice-core records, the MODIS and SeaWiFS images and determined the origin of dust, transport pathways and aerosol spatial distribution over central Asia and western Siberia in summer 2000, 2001 and 2002. The transport pathways were reconstructed on the basis of visibility observations and NCAR MM5-predicted winds with further validation against of satellite data and isotope- geochemical ice-core data analysis.

  11. Hot-start Giant Planets Form with Radiative Interiors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berardo, David; Cumming, Andrew, E-mail: david.berardo@mcgill.ca, E-mail: andrew.cumming@mcgill.ca

    In the hot-start core accretion formation model for gas giants, the interior of a planet is usually assumed to be fully convective. By calculating the detailed internal evolution of a planet assuming hot-start outer boundary conditions, we show that such a planet will in fact form with a radially increasing internal entropy profile, so that its interior will be radiative instead of convective. For a hot outer boundary, there is a minimum value for the entropy of the internal adiabat S {sub min} below which the accreting envelope does not match smoothly onto the interior, but instead deposits high entropymore » material onto the growing interior. One implication of this would be to at least temporarily halt the mixing of heavy elements within the planet, which are deposited by planetesimals accreted during formation. The compositional gradient this would impose could subsequently disrupt convection during post-accretion cooling, which would alter the observed cooling curve of the planet. However, even with a homogeneous composition, for which convection develops as the planet cools, the difference in cooling timescale will change the inferred mass of directly imaged gas giants.« less

  12. Ice core records of climate variability on the Third Pole with emphasis on the Guliya ice cap, western Kunlun Mountains

    NASA Astrophysics Data System (ADS)

    Thompson, Lonnie G.; Yao, Tandong; Davis, Mary E.; Mosley-Thompson, Ellen; Wu, Guangjian; Porter, Stacy E.; Xu, Baiqing; Lin, Ping-Nan; Wang, Ninglian; Beaudon, Emilie; Duan, Keqin; Sierra-Hernández, M. Roxana; Kenny, Donald V.

    2018-05-01

    Records of recent climate from ice cores drilled in 2015 on the Guliya ice cap in the western Kunlun Mountains of the Tibetan Plateau, which with the Himalaya comprises the Third Pole (TP), demonstrate that this region has become warmer and moister since at least the middle of the 19th century. Decadal-scale linkages are suggested between ice core temperature and snowfall proxies, North Atlantic oceanic and atmospheric processes, Arctic temperatures, and Indian summer monsoon intensity. Correlations between annual-scale oxygen isotopic ratios (δ18O) and tropical western Pacific and Indian Ocean sea surface temperatures are also demonstrated. Comparisons of climate records during the last millennium from ice cores acquired throughout the TP illustrate centennial-scale differences between monsoon and westerlies dominated regions. Among these records, Guliya shows the highest rate of warming since the end of the Little Ice Age, but δ18O data over the last millennium from TP ice cores support findings that elevation-dependent warming is most pronounced in the Himalaya. This, along with the decreasing precipitation rates in the Himalaya region, is having detrimental effects on the cryosphere. Although satellite monitoring of glaciers on the TP indicates changes in surface area, only a few have been directly monitored for mass balance and ablation from the surface. This type of ground-based study is essential to obtain a better understanding of the rate of ice shrinkage on the TP.

  13. Lake deposits record evidence of large post-1505 AD earthquakes in western Nepal

    NASA Astrophysics Data System (ADS)

    Ghazoui, Z.; Bertrand, S.; Vanneste, K.; Yokoyama, Y.; Van Der Beek, P.; Nomade, J.; Gajurel, A.

    2016-12-01

    According to historical records, the last large earthquake that ruptured the Main Frontal Thrust (MFT) in western Nepal occurred in 1505 AD. Since then, no evidence of other large earthquakes has been found in historical records or geological archives. In view of the catastrophic consequences to millions of inhabitants of Nepal and northern India, intense efforts currently focus on improving our understanding of past earthquake activity and complement the historical data on Himalayan earthquakes. Here we report a new record, based on earthquake-triggered turbidites in lakes. We use lake sediment records from Lake Rara, western Nepal, to reconstruct the occurrence of seismic events. The sediment cores were studied using a multi-proxy approach combining radiocarbon and 210Pb chronologies, physical properties (X-ray computerized axial tomography scan, Geotek multi-sensor core logger), high-resolution grain size, inorganic geochemistry (major elements by ITRAX XRF core scanning) and bulk organic geochemistry (C, N concentrations and stable isotopes). We identified several sequences of dense and layered fine sand mainly composed of mica, which we interpret as earthquake-triggered turbidites. Our results suggest the presence of a synchronous event between the two lake sites correlated with the well-known 1505 AD earthquake. In addition, our sediment records reveal five earthquake-triggered turbidites younger than the 1505 AD event. By comparison with historical archives, we relate one of those to the 1833 AD MFT rupture. The others may reflect successive ruptures of the Western Nepal Fault System. Our study sheds light on events that have not been recorded in historical chronicles. Those five MMI>7 earthquakes permit addressing the problem of missing slip on the MFT in western Nepal and reevaluating the risk of a large earthquake affecting western Nepal and North India.

  14. 3D-Printed Detector Band for Magnetic Off-Plane Flux Measurements in Laminated Machine Cores

    PubMed Central

    Pfützner, Helmut; Palkovits, Martin; Windischhofer, Andreas; Giefing, Markus

    2017-01-01

    Laminated soft magnetic cores of transformers, rotating machines etc. may exhibit complex 3D flux distributions with pronounced normal fluxes (off-plane fluxes), perpendicular to the plane of magnetization. As recent research activities have shown, detections of off-plane fluxes tend to be essential for the optimization of core performances aiming at a reduction of core losses and of audible noise. Conventional sensors for off-plane flux measurements tend to be either of high thickness, influencing the measured fluxes significantly, or require laborious preparations. In the current work, thin novel detector bands for effective and simple off-plane flux detections in laminated machine cores were manufactured. They are printed in an automatic way by an in-house developed 3D/2D assembler. The latter enables a unique combination of conductive and non-conductive materials. The detector bands were effectively tested in the interior of a two-package, three-phase model transformer core. They proved to be mechanically resilient, even for strong clamping of the core. PMID:29257063

  15. 3D-Printed Detector Band for Magnetic Off-Plane Flux Measurements in Laminated Machine Cores.

    PubMed

    Shilyashki, Georgi; Pfützner, Helmut; Palkovits, Martin; Windischhofer, Andreas; Giefing, Markus

    2017-12-19

    Laminated soft magnetic cores of transformers, rotating machines etc. may exhibit complex 3D flux distributions with pronounced normal fluxes (off-plane fluxes), perpendicular to the plane of magnetization. As recent research activities have shown, detections of off-plane fluxes tend to be essential for the optimization of core performances aiming at a reduction of core losses and of audible noise. Conventional sensors for off-plane flux measurements tend to be either of high thickness, influencing the measured fluxes significantly, or require laborious preparations. In the current work, thin novel detector bands for effective and simple off-plane flux detections in laminated machine cores were manufactured. They are printed in an automatic way by an in-house developed 3D/2D assembler. The latter enables a unique combination of conductive and non-conductive materials. The detector bands were effectively tested in the interior of a two-package, three-phase model transformer core. They proved to be mechanically resilient, even for strong clamping of the core.

  16. Regional paleohydrologic and paleoclimatic settings of wetland/lacustrine depositional systems in the Morrison Formation (Upper Jurassic), Western Interior, USA

    USGS Publications Warehouse

    Dunagan, S.P.; Turner, C.E.

    2004-01-01

    During deposition of the Upper Jurassic Morrison Formation, water that originated as precipitation in uplands to the west of the Western Interior depositional basin infiltrated regional aquifers that underlay the basin. This regional groundwater system delivered water into the otherwise dry continental interior basin where it discharged to form two major wetland/lacustrine successions. A freshwater carbonate wetland/lacustrine succession formed in the distal reaches of the basin, where regional groundwater discharged into the Denver-Julesburg Basin, which was a smaller structural basin within the more extensive Western Interior depositional basin. An alkaline-saline wetland/lacustrine complex (Lake T'oo'dichi') formed farther upstream, where shallower aquifers discharged into the San Juan/Paradox Basin, which was another small structural basin in the Western Interior depositional basin. These were both wetlands in the sense that groundwater was the major source of water. Input from surface and meteoric water was limited. In both basins, lacustrine conditions developed during episodes of increased input of surface water. Inclusion of wetlands in our interpretation of what had previously been considered largely lacustrine systems has important implications for paleohydrology and paleoclimatology. The distal carbonate wetland/lacustrine deposits are well developed in the Morrison Formation of east-central Colorado, occupying a stratigraphic interval that is equivalent to the "lower" Morrison but extends into the "upper" Morrison Formation. Sedimentologic, paleontologic, and isotopic evidence indicate that regional groundwater discharge maintained shallow, hydrologically open, well oxygenated, perennial carbonate wetlands and lakes despite the semi-arid climate. Wetland deposits include charophyte-rich wackestone and green mudstone. Lacustrine episodes, in which surface water input was significant, were times of carbonate and siliciclastic deposition in scarce deltaic and shoreline deposits. Marginal lacustrine deposits include ooid and skeletal packstone-grainstone, siltstone, and sandstone. Distal lacustrine units are skeletal mudstone-wackestone, microbialites, and laminated (siliciclastic) mudstone. Differentiation between wetlands and distal lacustrine units is not always possible. Palustrine features, Magadi-type chert (MTC), and evaporites record episodes of increased aridity and exposure. Farther upstream, during deposition of the upper part of the Brushy Basin Member, the ancestral Uncompahgre Uplift imposed a barrier to shallow, eastward-flowing groundwater that discharged into the San Juan/Paradox Basin on the upstream side of the uplift. This created the closed hydrologic setting necessary for development of an alkaline-saline wetland/lacustrine complex ("Lake" T'oo'dichi'). Silicic volcanic ash, delivered by prevailing winds from calderas west and southwest of the basin, contributed to the pore-water evolution in the sediments. A distinctive lateral hydrogeochemical gradient, reflecting increasing salinity and alkalinity in the pore waters, altered the ash to a variety of authigenic minerals that define concentric zones within the basin. The basinward progression of diagenetic mineral zones is smectite???clinoptilolite???analcime ??potassium feldspar???albite. The groundwater-fed wetlands were shallow and frequently evaporated to dryness. Scarce laminated gray mudstone beds record distinct episodes of freshwater lacustrine deposition that resulted from intermittent streams that carried detritus well out into the basin. ?? 2004 Elsevier B.V. All rights reserved.

  17. The Transculturing Self: A Philosophical Approach

    ERIC Educational Resources Information Center

    Monceri, Flavia

    2003-01-01

    The "Self" is a core notion in Western philosophy, which mainly defined it as an "autarchic individual", dependent on no "Other" whatsoever. Such a prevailing definition fails to recognise that just the "Other" is needed to properly define the "Self". As a result, Western mainstream philosophy…

  18. Sources and deposition of polycyclic aromatic hydrocarbons to western US national parks

    EPA Science Inventory

    Seasonal snowpack, lichens, and lake sediment cores were collected from fourteen lake catchments in eight western U.S. National Parks and analyzed for sixteen polycyclic aromatic hydrocarbons (PAHs) to determine their current and historical deposition, as well as to identify thei...

  19. Speciation in Western Scrub-Jays, Haldane’s rule, and genetic clines in secondary contact

    PubMed Central

    2014-01-01

    Background Haldane’s Rule, the tendency for the heterogametic sex to show reduced fertility in hybrid crosses, can obscure the signal of gene flow in mtDNA between species where females are heterogametic. Therefore, it is important when studying speciation and species limits in female-heterogametic species like birds to assess the signature of gene flow in the nuclear genome as well. We studied introgression of microsatellites and mtDNA across a secondary contact zone between coastal and interior lineages of Western Scrub-Jays (Aphelocoma californica) to test for a signature of Haldane’s Rule: a narrower cline of introgression in mtDNA compared to nuclear markers. Results Our initial phylogeographic analysis revealed that there is only one major area of contact between coastal and interior lineages and identified five genetic clusters with strong spatial structuring: Pacific Slope, Interior US, Edwards Plateau (Texas), Northern Mexico, and Southern Mexico. Consistent with predictions from Haldane’s Rule, mtDNA showed a narrower cline than nuclear markers across a transect through the hybrid zone. This result is not being driven by female-biased dispersal because neutral diffusion analysis, which included estimates of sex-specific dispersal rates, also showed less diffusion of mtDNA. Lineage-specific plumage traits were associated with nuclear genetic profiles for individuals in the hybrid zone, indicating that these differences are under genetic control. Conclusions This study adds to a growing list of studies that support predictions of Haldane’s Rule using cline analysis of multiple loci of differing inheritance modes, although alternate hypotheses like selection on different mtDNA types cannot be ruled out. That Haldane’s Rule appears to be operating in this system suggests a measure of reproductive isolation between the Pacific Slope and interior lineages. Based on a variety of evidence from the phenotype, ecology, and genetics, we recommend elevating three lineages to species level: A. californica (Pacific Slope); A. woodhouseii (Interior US plus Edwards Plateau plus Northern Mexico); A. sumichrasti (Southern Mexico). The distinctive Edwards Plateau population in Texas, which was monophyletic in mtDNA except for one individual, should be studied in greater detail given habitat threat. PMID:24938753

  20. Libration-driven flows in ellipsoidal shells

    NASA Astrophysics Data System (ADS)

    Lemasquerier, D.; Grannan, A. M.; Vidal, J.; Cébron, D.; Favier, B.; Le Bars, M.; Aurnou, J. M.

    2017-09-01

    Planets and satellites can undergo physical librations, which consist of forced periodic variations in their rotation rate induced by gravitational interactions with nearby bodies. This mechanical forcing may drive turbulence in interior fluid layers such as subsurface oceans and metallic liquid cores through a libration-driven elliptical instability (LDEI) that refers to the resonance of two inertial modes with the libration-induced base flow. LDEI has been studied in the case of a full ellipsoid. Here we address for the first time the question of the persistence of LDEI in the more geophysically relevant ellipsoidal shell geometries. In the experimental setup, an ellipsoidal container with spherical inner cores of different sizes is filled with water. Direct side view flow visualizations are made in the librating frame using Kalliroscope particles. A Fourier analysis of the light intensity fluctuations extracted from recorded movies shows that the presence of an inner core leads to spatial heterogeneities but does not prevent LDEI. Particle image velocimetry and direct numerical simulations are performed on selected cases to confirm our results. Additionally, our survey at a fixed forcing frequency and variable rotation period (i.e., variable Ekman number, E) shows that the libration amplitude at the instability threshold varies as ˜E0.65. This scaling is explained by a competition between surface and bulk dissipation. When extrapolating to planetary interior conditions, this leads to the E1/2 scaling commonly considered. We argue that Enceladus' subsurface ocean and the core of the exoplanet 55 CnC e should both be unstable to LDEI.

  1. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA.

    PubMed

    Stewart, Joseph A E; Wright, David H; Heckman, Katherine A

    2017-01-01

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species' core habitat has been lacking. Here, we report the extirpation of the American pika (Ochotona princeps), a temperature-sensitive small mammal, from a 165-km2 area located within its core habitat in California's Sierra Nevada mountains. While sites surrounding the area still maintain pikas, radiocarbon analyses of pika fecal pellets recovered within this area indicate that former patch occupancy ranges from before 1955, the beginning of the atmospheric spike in radiocarbon associated with above ground atomic bomb testing, to c. 1991. Despite an abundance of suitable rocky habitat climate warming appears to have precipitated their demise. Weather station data reveal a 1.9°C rise in local temperature and a significant decline in snowpack over the period of record, 1910-2015, pushing pika habitat into increasingly tenuous climate conditions during the period of extirpation. This is among the first accounts of an apparently climate-mediated, modern extirpation of a species from an interior portion of its geographic distribution, resulting in habitat fragmentation, and is the largest area yet reported for a modern-era pika extirpation. Our finding provides empirical support to model projections, indicating that even core areas of species habitat are vulnerable to climate change within a timeframe of decades.

  2. Condensed matter physics of planets - Puzzles, progress and predictions

    NASA Technical Reports Server (NTRS)

    Stevenson, D. J.

    1984-01-01

    Attention is given to some of the major unresolved issues concerned with the physics of planetary interiors. The important advances in observations, and experimental and theoretical investigations are briefly reviewed, and some areas for further study are identified, including: the characteristics of atomic and electronic degrees of freedom at the high pressures and temperatures typical of a condensed planetary core; the behavior of water at megabar pressures; and the nature of the core-alloy in the earth and in the core mantle phase boundary. Consideration is also given to the behavior of carbon at high pressures and temperatures in the presence of oxygen and hydrogen; the behavior of the volatile ice assemblage in Titan at pressures of 2-40 kbar; and the electrical conductivities of matter under planetary core conditions.

  3. Those Elusive Gravitational Waves

    ERIC Educational Resources Information Center

    MOSAIC, 1976

    1976-01-01

    The presence of gravitational waves was predicted by Einstein in his theory of General Relativity. Since then, scientists have been attempting to develop a detector sensitive enough to measure these cosmic signals. Once the presence of gravitational waves is confirmed, scientists can directly study star interiors, galaxy cores, or quasars. (MA)

  4. DETERMINATION OF THE INTERIOR STRUCTURE OF TRANSITING PLANETS IN MULTIPLE-PLANET SYSTEMS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Batygin, Konstantin; Bodenheimer, Peter; Laughlin, Gregory, E-mail: kbatygin@gps.caltech.ed

    Tidal dissipation within a short-period transiting extrasolar planet perturbed by a companion object can drive orbital evolution of the system to a so-called tidal fixed point, in which the apses of the transiting planet and its perturber are aligned, and variations in orbital eccentricities vanish. Significant contribution to the apsidal precession rate is made by gravitational quadrupole fields, created by the transiting planets tidal and rotational distortions. The fixed-point orbital eccentricity of the inner planet is therefore a strong function of its interior structure. We illustrate these ideas in the specific context of the recently discovered HAT-P-13 exoplanetary system, andmore » show that one can already glean important insights into the physical properties of the inner transiting planet. We present structural models of the planet, which indicate that its observed radius can be maintained for a one-parameter sequence of models that properly vary core mass and tidal energy dissipation in the interior. We use an octupole-order secular theory of the orbital dynamics to derive the dependence of the inner planet's eccentricity, e{sub b} , on its tidal Love number, k {sub 2b}. We find that the currently measured eccentricity, e{sub b} = 0.021 +- 0.009, implies 0.116 < k {sub 2b} < 0.425, 0 M {sub +} < M {sub core} < 120 M {sub +}, and 10, 000 < Q{sub b} < 300, 000. Improved measurement of the eccentricity will soon allow for far tighter limits to be placed on all of these quantities, and will provide an unprecedented probe into the interior structure of an extrasolar planet.« less

  5. Energy Transport Effects in Flaring Atmospheres Heated by Mixed Particle Beams

    NASA Astrophysics Data System (ADS)

    Zharkova, Valentina; Zharkov, Sergei; Macrae, Connor; Druett, Malcolm; Scullion, Eamon

    2016-07-01

    We investigate energy and particle transport in the whole flaring atmosphere from the corona to the photosphere and interior for the flaring events on the 1st July 2012, 6 and 7 September 2011 by using the RHESSI and SDO instruments as well as high-resolution observations from the Swedish 1-metre Solar Telescope (SST3) CRISP4 (CRisp Imaging Spectro-polarimeter). The observations include hard and soft X-ray emission, chromospheric emission in both H-alpha 656.3 nm core and continuum, as well as, in the near infra-red triplet Ca II 854.2 nm core and continuum channels and local helioseismic responses (sunquakes). The observations are compared with the simulations of hard X-ray emission and tested by hydrodynamic simulations of flaring atmospheres of the Sun heated by mixed particle beams. The temperature, density and macro-velocity variations of the ambient atmospheres are calculated for heating by mixed beams and the seismic response of the solar interior to generation of supersonic shocks moving into the solar interior. We investigate the termination depths of these shocks beneath the quiet photosphere levels and compare them with the parameters of seismic responses in the interior, or sunquakes (Zharkova and Zharkov, 2015). We also present an investigation of radiative conditions modelled in a full non-LTE approach for hydrogen during flare onsets with particular focus on Balmer and Paschen emission in the visible, near UV and near IR ranges and compare them with observations. The links between different observational features derived from HXR, optical and seismic emission are interpreted by different particle transport models that will allow independent evaluation of the particle transport scenarios.

  6. Preparation of magnetic core mesoporous shell microspheres with C18-modified interior pore-walls for fast extraction and analysis of phthalates in water samples.

    PubMed

    Li, Zhongbo; Huang, Danni; Fu, Chinfai; Wei, Biwen; Yu, Wenjia; Deng, Chunhui; Zhang, Xiangmin

    2011-09-16

    In this study, core-shell magnetic mesoporous microspheres with C18-functionalized interior pore-walls were synthesized through coating Fe(3)O(4) microspheres with a mesoporous inorganic-organic hybrid layer with a n-octadecyltriethoxysilane (C18TES) and tetraethyl orthosilicate (TEOS) as the silica source and cetyltrimethylammonia bromide (CTAB) as a template. The obtained C18-functionalized Fe(3)O(4)@mSiO(2) microspheres possess numerous C18 groups anchored in the interior pore-walls, large surface area (274.7 m(2)/g, high magnetization (40.8 emu/g) and superparamagnetism, uniform mesopores (4.1 nm), which makes them ideal absorbents for simple, fast, and efficient extraction and enrichment of hydrophobic organic compounds in water samples. Several kinds of phthalates were used as the model hydrophobic organic compounds to systematically evaluate the performance of the C18-functionalized Fe(3)O(4)@mSiO(2) microspheres in extracting hydrophobic molecules by using a gas chromatography-mass spectrometry. Various parameters, including eluting solvent, the amounts of absorbents, extraction time and elution time were optimized. Hydrophobic extraction was performed in the interior pore of magnetic mesoporous microspheres, and the materials had the anti-interference ability to macromolecular proteins, which was also investigated in the work. Under the optimized conditions, C18-functionalized Fe(3)O(4)@mSiO(2) microspheres were successfully used to analyze the real water samples. The results indicated that this novel method was fast, convenient and efficient for the target compounds and could avoid being interfered by macromolecules. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Preparing for InSight - using the continuous seismic data flow to investigate the deep interior of Mars

    NASA Astrophysics Data System (ADS)

    Hempel, S.; Garcia, R.; Weber, R. C.; Schmerr, N. C.; Panning, M. P.; Lognonne, P. H.; Banerdt, W. B.

    2016-12-01

    Complementary to investigating ray theoretically predictable parameters to explore the deep interior of Mars (see AGU contribution by R. Weber et al.), this paper presents the waveform approach to illuminate the lowermost mantle and core-mantle boundary of Mars. In preparation to the NASA discovery mission InSight, scheduled for launch in May, 2018, we produce synthetic waveforms considering realistic combinations of sources and a single receiver, as well as noise models. Due to a lack of constraints on the scattering properties of the Martian crust and mantle, we assume Earth-like scattering as a minimum and Moon-like scattering as a maximum possibility. Various seismic attenuation models are also investigated. InSight is set up to deliver event data as well as a continuous data flow. Where ray theoretical approaches will investigate the event data, the continuous data flow may contain signals reflected multiple times off the same reflector, e.g. the underside of the lithosphere, or the core-mantle boundary. It may also contain signals of individual events not detected or interfering wavefields radiated off multiple undetected events creating 'seismic noise'. We will use AxiSEM to simulate a continuous data flow for these cases for various 1D and 2D Mars models, and explore the possibilities of seismic interferometry to use seismic information hidden in the coda to investigate the deep interior of Mars.

  8. Gravastars in f (R ,T ) gravity

    NASA Astrophysics Data System (ADS)

    Das, Amit; Ghosh, Shounak; Guha, B. K.; Das, Swapan; Rahaman, Farook; Ray, Saibal

    2017-06-01

    We propose a unique stellar model under the f (R ,T ) gravity by using the conjecture of Mazur-Mottola [P. Mazur and E. Mottola, Report No. LA-UR-01-5067, P. Mazur and E. Mottola, Proc. Natl. Acad. Sci. USA 101, 9545 (2004), 10.1073/pnas.0402717101] which is known as gravastar and a viable alternative to the black hole as available in literature. This gravastar is described by the three different regions, viz., (I) Interior core region, (II) Intermediate thin shell, and (III) Exterior spherical region. The pressure within the interior region is equal to the constant negative matter density which provides a repulsive force over the thin spherical shell. This thin shell is assumed to be formed by a fluid of ultrarelativistic plasma and the pressure, which is directly proportional to the matter-energy density according to Zel'dovich's conjecture of stiff fluid [Y. B. Zel'dovich, Mon. Not. R. Astron. Soc. 160, 1 (1972), 10.1093/mnras/160.1.1P], does counterbalance the repulsive force exerted by the interior core region. The exterior spherical region is completely vacuum and assumed to be de Sitter spacetime which can be described by the Schwarzschild solution. Under this specification we find out a set of exact and singularity-free solution of the gravastar which presents several other physically valid features within the framework of alternative gravity.

  9. Spatial Variability of accumulation across the Western Greenland Ice Sheet Percolation Zone from ground-penetrating-radar and shallow firn cores

    NASA Astrophysics Data System (ADS)

    Lewis, G.; Osterberg, E. C.; Hawley, R. L.; Marshall, H. P.; Birkel, S. D.; Meehan, T. G.; Graeter, K.; Overly, T. B.; McCarthy, F.

    2017-12-01

    The mass balance of the Greenland Ice Sheet (GrIS) in a warming climate is of critical interest to scientists and the general public in the context of future sea-level rise. Increased melting in the GrIS percolation zone over the past several decades has led to increased mass loss at lower elevations due to recent warming. Uncertainties in mass balance are especially large in regions with sparse and/or outdated in situ measurements. This study is the first to calculate in situ accumulation over a large region of western Greenland since the Program for Arctic Regional Climate Assessment campaign during the 1990s. Here we analyze 5000 km of 400 MHz ground penetrating radar data and sixteen 25-33 m-long firn cores in the western GrIS percolation zone to determine snow accumulation over the past 50 years. The cores and radar data were collected as part of the 2016-2017 Greenland Traverse for Accumulation and Climate Studies (GreenTrACS). With the cores and radar profiles we capture spatial accumulation gradients between 1850-2500 m a.s.l and up to Summit Station. We calculate accumulation rates and use them to validate five widely used regional climate models and to compare with IceBridge snow and accumulation radars. Our results indicate that while the models capture most regional spatial climate patterns, they lack the small-scale spatial variability captured by in situ measurements. Additionally, we evaluate temporal trends in accumulation at ice core locations and throughout the traverse. Finally, we use empirical orthogonal function and correlation analyses to investigate the principal drivers of radar-derived accumulation rates across the western GrIS percolation zone, including major North Atlantic climate modes such as the North Atlantic Oscillation, Atlantic Multidecadal Oscillation, and Greenland Blocking Index.

  10. Past and future hydro-climatic change and the 2015 drought in the interior of western Canada

    NASA Astrophysics Data System (ADS)

    DeBeer, C. M.; Wheater, H. S.; Pomeroy, J. W.; Stewart, R. E.; Szeto, K.; Brimelow, J.; Chun, K. P.; Masud, M. B.; Bonsal, B. R.

    2015-12-01

    The interior of western Canada has experienced rapid and severe hydro-climatic change in recent decades. This is projected to continue in future. Since 1950, mean annual air temperature has increased by 2 °C (4 °C increase in winter daily means) with associated changes in cryospheric regime. Changes in precipitation have varied regionally; in the Prairies there has been a decrease in winter precipitation, shift from snowfall to rainfall, and increased clustering of summer rainfall events into multiple day storms. Regionally, river discharge indicates an earlier spring freshet and increased incidence of rain-on-snow peak flow events, but otherwise mixed responses due to multiple process interactions. In winter/spring 2015, persistent anomalous ridging conditions developed over western North America causing widespread drought. This produced abnormally warm and dry conditions over the Rocky Mountain headwaters of the Mackenzie and Saskatchewan Rivers, resulting in low spring snowpacks that melted earlier than normal and were followed by an atypical lack of spring rainfall. By summer 2015, most of western Canada was subject to extreme drought conditions leading to record dry soil moisture conditions in parts of the Prairies during a key crop growth time, streamflows that were greatly diminished, and extensive wildfires across the Boreal Forest. The importance of the warmer winter to this drought and the contextual trend for increasing winter warmth provide new insight into the impact of climate warming on droughts in cold regions. This talk will discuss efforts by the Changing Cold Regions Network (CCRN; www.ccrnetwork.ca) to understand and diagnose the 2015 drought, its potential linkages with the concurrent California drought and other continental events, and its relevance in the context of historical and predicted future climate change.

  11. Nanoparticle functionalised small-core suspended-core fibre - a novel platform for efficient sensing.

    PubMed

    Doherty, Brenda; Csáki, Andrea; Thiele, Matthias; Zeisberger, Matthias; Schwuchow, Anka; Kobelke, Jens; Fritzsche, Wolfgang; Schmidt, Markus A

    2017-02-01

    Detecting small quantities of specific target molecules is of major importance within bioanalytics for efficient disease diagnostics. One promising sensing approach relies on combining plasmonically-active waveguides with microfluidics yielding an easy-to-use sensing platform. Here we introduce suspended-core fibres containing immobilised plasmonic nanoparticles surrounding the guiding core as a concept for an entirely integrated optofluidic platform for efficient refractive index sensing. Due to the extremely small optical core and the large adjacent microfluidic channels, over two orders of magnitude of nanoparticle coverage densities have been accessed with millimetre-long sample lengths showing refractive index sensitivities of 170 nm/RIU for aqueous analytes where the fibre interior is functionalised by gold nanospheres. Our concept represents a fully integrated optofluidic sensing system demanding small sample volumes and allowing for real-time analyte monitoring, both of which are highly relevant within invasive bioanalytics, particularly within molecular disease diagnostics and environmental science.

  12. Paleoclimate effects and geographic barriers shape regional population genetic structure of blackbrush (Coleogyne ramosissima: Rosaceae)

    Treesearch

    Bryce A. Richardson; Susan E. Meyer

    2012-01-01

    Coleogyne ramosissima Torr. (blackbrush) is a dominant xerophytic shrub species in the ecotone between the warm and cold deserts of interior western North America. Amplified fragment length polymorphisms (AFLPs) were used to survey genetic diversity and population genetic structure at 14 collection sites across the species range. Analysis revealed significant...

  13. Small-diameter trees used for chemithermomechanical pulps.

    Treesearch

    Gary C. Myers; R. James Barbour; Said M. AbuBakr

    2003-01-01

    To restore and maintain forest ecosystem health and function in the western interior of the United States, many small-diameter stems need to be removed from densely stocked stands. In general, these materials are underutilized. Information on the properties of these resources is needed to help forest managers understand when timber sales are a viable option to...

  14. Estimating canopy bulk density and canopy base height for interior western US conifer stands

    Treesearch

    Seth A. Ex; Frederick W. Smith; Tara L. Keyser; Stephanie A. Rebain

    2016-01-01

    Crown fire hazard is often quantified using effective canopy bulk density (CBD) and canopy base height (CBH). When CBD and CBH are estimated using nonlocal crown fuel biomass allometries and uniform crown fuel distribution assumptions, as is common practice, values may differ from estimates made using local allometries and nonuniform...

  15. Optimizing lodgepole pine submerchantable log thermomechanical pulp

    Treesearch

    Gary C. Myers

    2004-01-01

    To restore and maintain ecosystem health and function in the western interior of the United States, many small-diameter stems need to be removed from densely stocked stands. These stems are considered nonusable or underutilized (good, economical uses need to be developed). As of now, the most logical use for the small-diameter resource is pulp. In this study,...

  16. 76 FR 379 - Notice of Intent To Prepare an Environmental Impact Statement for the TransWest Express 600 kV...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-04

    ... Management, Wyoming State Office, TransWest Express Transmission Project, P.O. Box 20678, 5353 Yellowstone... DEPARTMENT OF THE INTERIOR Bureau of Land Management DEPARTMENT OF ENERGY Western Area Power... Intent To Prepare an Environmental Impact Statement for the TransWest Express 600 kV Direct Current...

  17. Survey for Armillaria by plant associations in northern Arizona

    Treesearch

    Christ W. Hoffman; Robert L. Mathiasen; Richard W. Hofstetter; Mary Lou Fairweather; John D. Shaw; John W. Hanna; Ned B. Klopfenstein

    2014-01-01

    Fungi in the genus Armillaria are associated with an important disease of deciduous and coniferous trees and shrubs in western North America. This study examined the distribution of Armillaria by forest habitat types on the Kaibab National Forest and northern Coconino National Forest, Arizona. Over 400 trees were examined for Armillaria in 76 Interior West Forest...

  18. Cold hardiness in Wyoming big sagebrush seedlings: implications for nursery production and outplanting

    Treesearch

    Kayla R. Herriman; Anthony S. Davis

    2012-01-01

    Throughout much of the interior western United States, Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) is a keystone species, serving an important ecological role in sagebrush steppe and Great Basin sagebrush vegetation types (Lysne 2005, Lambrecht et al. 2007). Over the past century, these ecosystems have been degraded by fire, invasive species, and...

  19. Stability of the large tree component in treated and untreated late-seral interior ponderosa pine stands

    Treesearch

    Martin W. Ritchie; Brian M. Wing; Todd A. Hamilton

    2008-01-01

    Ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) stands with late-seral features are found infrequently, owing to past management activities throughout western North America. Thus, management objectives often focus on maintaining existing late-seral stands. Observations over a 65 year period, of stands with not past history of harvest,...

  20. 76 FR 77008 - Notice of Administrative Boundary Change for Bureau of Land Management Offices in Montana To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-09

    ... Lewis and Clark County AGENCY: Bureau of Land Management, Interior. ACTION: Notice. SUMMARY: The... realign Lewis and Clark County, currently a split county between the two offices, to the Western Montana... Broadwater, Deer Lodge, Gallatin, Jefferson, Lewis and Clark, Park, Silver Bow and the northern portion of...

  1. 75 FR 6380 - Provo River Project Rate Order No. WAPA-149

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-09

    ... kilowatts. The PRP power is marketed according to a marketing plan that was approved and published in the Federal Register on November 21, 1994. This marketing plan allows Western to market the output of the PRP... Secretary of Energy the power marketing functions of the Secretary of the Department of the Interior and the...

  2. Effects of fire on intangible cultural resources: Moving toward a landscape approach [Chapter 8

    Treesearch

    John R. Welch

    2012-01-01

    Long before the Secretaries of the Departments of Agriculture and Interior signed the Federal Wildland Fire Management Policy in 1995, most land and resource professionals in the United States had recognized unprecedented fuel accumulations in western forests as management priorities. The Policy, its 2001 revision, the 2003 Healthy Forests Restoration Act, and the...

  3. Objectives and considerations for wildland fuel treatment in forested ecosystems of the interior western United States

    Treesearch

    Elizabeth D. Reinhardt; Robert E. Keane; David E. Calkin; Jack D. Cohen

    2008-01-01

    Many natural resource agencies and organizations recognize the importance of fuel treatments as tools for reducing fire hazards and restoring ecosystems. However, there continues to be confusion and misconception about fuel treatments and their implementation and effects in fire-prone landscapes across the United States. This paper (1) summarizes objectives, methods,...

  4. Final Report: Synthesis of aquatic climate change vulnerability assessments for the Interior West

    Treesearch

    Megan M. Friggens; Carly K. Woodlief

    2015-01-01

    Water is a critical resource for humans and ecological systems in the western United States. Aquatic ecosystems including lakes, rivers, riparian areas and wetlands, are at high risk of climate impacts because they experience relatively high exposure to climate fluctuations and extremes. In turn, impacts arising from climate change are far reaching because these...

  5. 77 FR 20411 - Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Southline...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-04

    ... DEPARTMENT OF THE INTERIOR Bureau of Land Management DEPARTMENT OF ENERGY Western Area Power...-0474) and Possible Land Use Plan Amendments AGENCY: Bureau of Land Management, U.S. Department of the... Land Policy and Management Act of 1976 (FLPMA), as amended, the Bureau of Land Management (BLM) Las...

  6. Fire on the early western landscape: An annotated record of wildland fires 1776-1900

    Treesearch

    George E. Gruell

    1985-01-01

    Scientific and historical literature was searched for documented accounts of early fires in the '"interior West" - Montana, Wyoming, Idaho, Utah, Nevada, and eastern Oregon. One hundred and forty-five accounts of fires by 44 observers were found. The majority of accounts described fires in progress. A smaller proportion referred to burned areas...

  7. Disturbance and Climate Change in the Interior West (Chapter 6)

    Treesearch

    Paulette L. Ford; Jeanne K. Chambers; Sharon J. Coe; Burton C. Pendleton

    2012-01-01

    Within the continental United States, average annual temperature increased during the Twentieth Century by approximately 0.65 ºC. The most extreme warming occurred throughout the northern and western United States (IPCC 2007a; Williams and others 2010). Disturbances such as fire, drought, grazing, urbanization, and energy development are predicted to have a heightened...

  8. Broadscale assessment of aquatic species and habitats [Chapter 4

    Treesearch

    Danny C. Lee; James R. Sedell; Bruce F. Rieman; Russell F. Thurow; Jack E. Williams

    1997-01-01

    In this chapter, we report on a broad-scale scientific assessment of aquatic resources conducted as part of the Interior Columbia Basin Ecosystem Management Project. Our assessment area, collectively referred to as the Basin, includes the Columbia River Basin east of the crest of the Cascade Mountains (Washington, Oregon, Idaho, western Montana, and small portions of...

  9. Subsurface Agricultural Irrigation Drainage: The Need for Regulation

    Treesearch

    A. Dennis Lemly

    1993-01-01

    Subsurface drainage resulting from irrigated agriculture is a toxic threat to fish and wildlife resources throughout the western United States. Studies by the U.S. Department of the Interior show that migratory waterfowl have been poisoned by drainwater contaminants on at least six national wildlife refuges. Allowing this poisoning to continue is a violation of the...

  10. Glacigenic landforms and sediments of the Western Irish Shelf

    NASA Astrophysics Data System (ADS)

    McCarron, Stephen; Monteys, Xavier; Toms, Lee

    2013-04-01

    Vibrocoring of possible glacigenic landforms identified from high resolution bathymetric coverage of the Irish Shelf by the Irish National Seabed Survey (INSS) has provided several clusters of short (<3m) cores that, due to a regional post-glacial erosional event, comprise last glacial age stratigraphies. In addition, new shallow seismic data and sedimentological information from across the Western Irish Shelf provide new insights into aspects of the nature, timing and pattern of shelf occupation by grounded lobate extensions of the last Irish Ice Sheet. Restricted chronological control of deglacial sequences in several cores indicates that northern parts of the western mid-shelf (south of a prominent outer Donegal Bay ridge) were ice free by ~24 ka B.P., and that ice had also probably retreated from outer shelf positions (as far west as the Porcupine Bank) at or before this time.

  11. A long-lived lunar core dynamo.

    PubMed

    Shea, Erin K; Weiss, Benjamin P; Cassata, William S; Shuster, David L; Tikoo, Sonia M; Gattacceca, Jérôme; Grove, Timothy L; Fuller, Michael D

    2012-01-27

    Paleomagnetic measurements indicate that a core dynamo probably existed on the Moon 4.2 billion years ago. However, the subsequent history of the lunar core dynamo is unknown. Here we report paleomagnetic, petrologic, and (40)Ar/(39)Ar thermochronometry measurements on the 3.7-billion-year-old mare basalt sample 10020. This sample contains a high-coercivity magnetization acquired in a stable field of at least ~12 microteslas. These data extend the known lifetime of the lunar dynamo by 500 million years. Such a long-lived lunar dynamo probably required a power source other than thermochemical convection from secular cooling of the lunar interior. The inferred strong intensity of the lunar paleofield presents a challenge to current dynamo theory.

  12. A simple 3-D numerical model of thermal convection in Earth's growing inner core: on the possibility of the formation of the degree-one structure with lateral viscosity variations

    NASA Astrophysics Data System (ADS)

    Yoshida, M.

    2015-12-01

    An east-west hemispherically asymmetric structure for Earth's inner core has been suggested by various seismological evidence, but its origin is not clearly understood. Here, to investigate the possibility of an "endogenic origin" for the degree-one thermal/mechanical structure of the inner core, I performed new numerical simulations of thermal convection in the growing inner core. A setup value that controls the viscosity contrast between the inner core boundary and the interior of the inner core, ΔηT, was taken as a free parameter. Results show that the degree-one structure only appeared for a limited range of ΔηT; such a scenario may be possible but is not considered probable for the real Earth. The degree-one structure may have been realized by an "exogenous factor" due to the planetary-scale thermal coupling among the lower mantle, the outer core, and the inner core, not by an endogenic factor due to the internal rheological heterogeneity.

  13. Fossil Cores In The Kepler Data

    NASA Astrophysics Data System (ADS)

    Jackson, Brian

    Most gas giant exoplanets with orbital periods < few days are unstable against tidal decay and may be tidally disrupted before their host stars leave the main sequence. These gas giants probably contain rocky/icy cores, and so their cores will be stranded near their progenitor's Roche limit (few hours orbital period). These fossil cores will evade the Kepler mission's transit search because it is focused on periods > 0.5 days, but finding these fossil cores would provide unprecedented insights into planetary interiors and formation ? e.g., they would be a smoking gun favoring formation of gas giants via core accretion. We propose to search for and characterize fossil cores in the Kepler dataset. We will vet candidates using the Kepler photometry and auxiliary data, collect ground-based spectra of the host stars and radial-velocity (RV) and adaptive optics (AO) data to corroborate candidates. We will also constrain stellar tidal dissipation efficiencies (parameterized by Q) by determining our survey's completeness, elucidating dynamical origins and evolution of exoplanets even if we find no fossil cores. Our preliminary search has already found several dozen candidates, so the proposed survey has a high likelihood of success.

  14. 43 CFR 3931.80 - Core or test hole samples and cuttings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) MANAGEMENT OF OIL SHALE.... The records must include a log of all strata penetrated and conditions encountered, such as water, gas... operation or any deposit of oil, gas, other mineral substances, or ground water. (c) Operators may convert...

  15. 43 CFR 3931.80 - Core or test hole samples and cuttings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MANAGEMENT OF OIL SHALE.... The records must include a log of all strata penetrated and conditions encountered, such as water, gas... operation or any deposit of oil, gas, other mineral substances, or ground water. (c) Operators may convert...

  16. 43 CFR 3931.80 - Core or test hole samples and cuttings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MANAGEMENT OF OIL SHALE.... The records must include a log of all strata penetrated and conditions encountered, such as water, gas... operation or any deposit of oil, gas, other mineral substances, or ground water. (c) Operators may convert...

  17. 43 CFR 3931.80 - Core or test hole samples and cuttings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MANAGEMENT OF OIL SHALE.... The records must include a log of all strata penetrated and conditions encountered, such as water, gas... operation or any deposit of oil, gas, other mineral substances, or ground water. (c) Operators may convert...

  18. Are diamond-bearing Cretaceous kimberlites related to shallow-angle subduction beneath western North America?

    NASA Astrophysics Data System (ADS)

    Currie, C. A.; Beaumont, C.

    2009-05-01

    The origin of deep-seated magmatism (in particular, kimberlites and lamproites) within continental plate interiors remains enigmatic in the context of plate tectonic theory. One hypothesis proposes a relationship between kimberlite occurrence and lithospheric subduction, such that a subducting plate releases fluids below a continental craton, triggering melting of the deep lithosphere and magmatism (Sharp, 1974; McCandless, 1999). This study provides a quantitative evaluation of this hypothesis, focusing on the Late Cretaceous- Eocene (105-50 Ma) kimberlites and lamproites of western North America. These magmas were emplaced along a corridor of Archean and Proterozoic lithosphere, 1000-1500 km inboard of the plate margin separating the subducting Farallon Plate and continental North America Plate. Kimberlite-lamproite magmatism coincides with tectonic events, including the Laramide orogeny, shut-down of the Sierra Nevada arc, and eastward migration of volcanism, that are commonly attributed to a change in Farallon Plate geometry to a shallow-angle trajectory (<25° dip). Thermal-mechanical numerical models demonstrate that rapid Cretaceous plate convergence rates and enhanced westward velocity of North America result in shallow-angle subduction that places the Farallon Plate beneath the western edge of the cratonic interior of North America. This geometry is consistent with the observed continental dynamic subsidence that lead to the development of the Western Interior Seaway. The models also show that the subducting plate has a cool thermal structure, and subducted hydrous minerals (serpentine, phengite and phlogopite) remain stable to more than 1200 km from the trench, where they may break down and release fluids that infiltrate the overlying craton lithosphere. This is supported by geochemical studies that indicate metasomatism of the Colorado Plateau and Wyoming craton mantle lithosphere by an aqueous fluid and/or silicate melt with a subduction signature. Through Cretaceous shallow-angle subduction, the Farallon Plate was in a position to mechanically and chemically interact with North American craton lithosphere at the time of kimberlite-lamproite magmatism, making the subduction hypothesis a viable mechanism for the genesis of these magmas. REFERENCES: McCandless, T.E., Proceedings of the 7th International Kimberlite Conference, v.2, pp.545-549, 1999; Sharp, W.E., Earth Planet. Sci. Lett., v.21, pp.351-354, 1974.

  19. A study of the required Rayleigh number to sustain dynamo with various inner core radius

    NASA Astrophysics Data System (ADS)

    Nishida, Y.; Katoh, Y.; Matsui, H.; Kumamoto, A.

    2017-12-01

    It is widely accepted that the geomagnetic field is sustained by thermal and compositional driven convections of a liquid iron alloy in the outer core. The generation process of the geomagnetic field has been studied by a number of MHD dynamo simulations. Recent studies of the ratio of the Earth's core evolution suggest that the inner solid core radius ri to the outer liquid core radius ro changed from ri/ro = 0 to 0.35 during the last one billion years. There are some studies of dynamo in the early Earth with smaller inner core than the present. Heimpel et al. (2005) revealed the Rayleigh number Ra of the onset of dynamo process as a function of ri/ro from simulation, while paleomagnetic observation shows that the geomagnetic field has been sustained for 3.5 billion years. While Heimpel and Evans (2013) studied dynamo processes taking into account the thermal history of the Earth's interior, there were few cases corresponding to the early Earth. Driscoll (2016) performed a series of dynamo based on a thermal evolution model. Despite a number of dynamo simulations, dynamo process occurring in the interior of the early Earth has not been fully understood because the magnetic Prandtl numbers in these simulations are much larger than that for the actual outer core.In the present study, we performed thermally driven dynamo simulations with different aspect ratio ri/ro = 0.15, 0.25 and 0.35 to evaluate the critical Ra for the thermal convection and required Ra to maintain the dynamo. For this purpose, we performed simulations with various Ra and fixed the other control parameters such as the Ekman, Prandtl, and magnetic Prandtl numbers. For the initial condition and boundary conditions, we followed the dynamo benchmark case 1 by Christensen et al. (2001). The results show that the critical Ra increases with the smaller aspect ratio ri/ro. It is confirmed that larger amplitude of buoyancy is required in the smaller inner core to maintain dynamo.

  20. Biomes of western North America at 18,000, 6000 and 0 14C yr BP reconstructed from pollen and packrat midden data

    USGS Publications Warehouse

    Thompson, R.S.; Anderson, K.H.

    2000-01-01

    A new compilation of pollen and packrat midden data from western North America provides a refined reconstruction of the composition and distribution of biomes in western North America for today and for 6000 and 18,000 radiocarbon years before present (14C yr BP). Modern biomes in western North America are adequately portrayed by pollen assemblages from lakes and bogs. Forest biomes in western North America share many taxa in their pollen spectra and it can be difficult to discriminate among these biomes. Plant macrofossils from packrat middens provide reliable identification of modern biomes from arid and semiarid regions, and this may also be true in similar environments in other parts of the world. However, a weighting factor for trees and shrubs must be used to reliably reconstruct modern biomes from plant macrofossils. A new biome, open conifer woodland, which includes eurythermic conifers and steppe plants, was defined to categorize much of the current and past vegetation of the semiarid interior of western North America. At 6000 14C yr BP, the forest biomes of the coastal Pacific North-west and the desert biomes of the South-west were in near-modern positions. Biomes in the interior Pacific North-west differed from those of today in that taiga prevailed in modern cool/cold mixed forests. Steppe was present in areas occupied today by open conifer woodland in the northern Great Basin, while in the central and southern Rocky Mountains forests grew where steppe grows today. During the mid-Holocene, cool conifer forests were expanded in the Rocky Mountains (relative to today) but contracted in the Sierra Nevada. These differences from the forests of today imply different climatic histories in these two regions between 6000 14C yr BP and today. At 18,000 14C yr BP, deserts were absent from the South-west and the coverage of open conifer woodland was greatly expanded relative to today. Steppe and tundra were present in much of the region now covered by forests in the Pacific North-west.

  1. Mitochondrial filaments and clusters as intracellular power-transmitting cables.

    PubMed

    Skulachev, V P

    2001-01-01

    Mitochondria exist in two interconverting forms; as small isolated particles, and as extended filaments, networks or clusters connected with intermitochondrial junctions. Extended mitochondria can represent electrically united systems, which can facilitate energy delivery from the cell periphery to the cell core and organize antioxidant defence of the cell interior when O2 is consumed by mitochondrial clusters near the the outer cell membrane, and protonic potential is transmitted to the cell core mitochondria to form ATP. As to small mitochondria, they might represent a transportable form of these organelles.

  2. Evidence for a Second Martian Dynamo from Electron Reflection Magnetometry

    NASA Technical Reports Server (NTRS)

    Lillis, R. J.; Manga, M.; Mitchell, D. L.; Lin, R. P.; Acuna, M. H.

    2005-01-01

    Present-day Mars does not possess an active core dynamo and associated global magnetic field. However, the discovery of intensely magnetized crust in Mars Southern hemisphere implies that a Martian dynamo has existed in the past. Resolving the history of the Martian core dynamo is important for understanding the evolution of the planet's interior. Moreover, because the global magnetic field provided by an active dynamo can shield the atmosphere from erosion by the solar wind, it may have influenced past Martian climate. Additional information is included in the original extended abstract.

  3. Estimation of the interior parameters from Mars nutations and from Doppler measurements

    NASA Astrophysics Data System (ADS)

    Yseboodt, M.; Rivoldini, A.; Le Maistre, S.; Dehant, V. M. A.

    2017-12-01

    The presence of a liquid core inside Mars changes the nutations: the nutation amplitudes can be resonantly amplified because of a free mode, called the free core nutation (FCN).We quantify how the internal structure, in particular the size of the core, affects the nutation amplifications and the Doppler observable between a Martian lander and the Earth.Present day core size estimates suggest that the effect is the largest on the prograde semi-annual and retrograde ter-annual nutation.We solve the inverse problem assuming a given precision on the nutation amplifications provided by an extensive set of geodesy measurements and we estimate the precision on the core properties. Such measurements will be available in the near future thanks to the geodesy experiments RISE (InSight mission) and LaRa (ExoMars mission).We find that the precision on the core properties is very dependent on the proximity of the FCN period to the ter-annual forcing (-229 days) and the assumed a priori precision on the nutations.

  4. Identifying a New Mechanism of HIV Core Formation | Center for Cancer Research

    Cancer.gov

    During the maturation of human immunodeficiency virus 1 (HIV-1), viral particles transition from a noninfectious form to an infectious one, and this conversion requires the cleavage of the HIV-1 Gag polyprotein. Gag is made up of three structural proteins—matrix (MA), capsid (CA), and nucleocapsid (NC)—connected by linkers. MA anchors Gag in the membrane, CA surrounds the HIV-1 core, and NC packages the viral RNA within the core. Current models of the development of HIV-1 suggest that when CA is cleaved from Gag it dissociates from the membrane and moves into the virus interior before nucleating, in a concentration-dependent manner, into the core, which is the last step in virus maturation. The core is thought to grow from its narrow end stopping only when it reaches the opposite side of the virus membrane. Since blocking the formation of infectious viral particles is an important therapeutic strategy, it is critical to understand the detailed mechanism of core maturation.

  5. Time-dependent heat transfer in the spherical Earth: Implications on the power and thermal evolution of the core

    NASA Astrophysics Data System (ADS)

    Hofmeister, A. M.; Criss, R. E.

    2015-12-01

    We quantitatively investigate the time-dependence of heat conduction for a post-core, spherical Earth that is not convecting, due to compositional layering, based on hundreds of measurements of thermal diffusivity (D) for insulators and metals. Consistency of our solutions for widely ranging input parameters indicates how additional heat transfer mechanisms (mantle magmatism and convection) affect thermal evolution of the core. We consider 1) interior starting temperatures (T) of 273-5000 K, which represent variations in primordial heat, 2) different distributions and decay of long-lived radioactive isotopes, 3) additional heat sources in the core (primordial or latent heat), and 4) variable depth-T dependence of D. Our new analytical solution for cooling of a constant D sphere validates our numerical results. The bottom line is that the thermally insulating nature of minerals, combined with constraints of spherical geometry, limits steep thermal gradients to the upper mantle, consistent with the short length scale (x ~700 km) of cooling over t = 4.5 Ga indicated by dimensional analysis [x2 ~ 4Dt], and with plate tectonics. Consequently, interior temperatures vary little so the core has remained hot and is possibly warming. Findings include: 1) Constant vs. variable D affects thermal profiles only in detail, with D for the metallic core being inconsequential. 2) The hottest zone in Earth may lie in the uppermost lower mantle; 3) Most radiogenic heat is released in Earth's outermost 1000 km thereby driving an active outer shell; 4) Earth's core is essentially isothermal and is thus best described by the liquid-solid phase boundary; 5) Deeply sequestered radioactivity or other heat will melt the core rather than by run the dynamo (note that the heat needed to have melted the outer core is 10% of radiogenic heat generated over Earth's history); 6) Inefficient cooling of an Earth-sized mass means that heat essentially remains where it is generated, until it is removed by magmatism; 7) Importantly, the observed plate velocities are consistent with a Nusselt number of 1, i.e. the present day cooling is essentially conductive. Conductive cooling plus magmatism largely governs Earth's thermal structure and dynamics, below a unicellular upper mantle. Core dynamics and magnetism are likely driven by rotational effects.

  6. Mechanical Properties of Degraded PMR-15 Resin

    NASA Technical Reports Server (NTRS)

    Tsuji, Luis C.; McManus, Hugh L.; Bowles, Kenneth J.

    1998-01-01

    Thermo-oxidative aging produces a non-uniform degradation state in PMR-15 resin. A surface layer, usually attributed to oxidative degradation, forms. This surface layer has different properties from the inner material. A set of material tests was designed to separate the properties of the oxidized surface layer from the properties of interior material. Test specimens were aged at 316 C in either air or nitrogen, for durations of up to 800 hours. The thickness of the oxidized surface layer in air aged specimens, and the shrinkage and Coefficient of Thermal Expansion (CTE) of nitrogen aged specimens were measured directly. Four-point-bend tests were performed to determine modulus of both the oxidized surface layer and the interior material. Bimaterial strip specimens consisting of oxidized surface material and unoxidized interior material were constructed and used to determine surface layer shrinkage and CTE. Results confirm that the surface layer and core materials have substantially different properties.

  7. Late Quaternary vegetation and climate history of the central Bering land bridge from St. Michael Island, western Alaska

    USGS Publications Warehouse

    Ager, T.A.

    2003-01-01

    Pollen analysis of a sediment core from Zagoskin Lake on St. Michael Island, northeast Bering Sea, provides a history of vegetation and climate for the central Bering land bridge and adjacent western Alaska for the past ???30,000 14C yr B.P. During the late middle Wisconsin interstadial (???30,000-26,000 14C yr B.P.) vegetation was dominated by graminoid-herb tundra with willows (Salix) and minor dwarf birch (Betula nana) and Ericales. During the late Wisconsin glacial interval (26,000-15,000 14C yr B.P.) vegetation was graminoid-herb tundra with willows, but with fewer dwarf birch and Ericales, and more herb types associated with dry habitats and disturbed soils. Grasses (Poaceae) dominated during the peak of this glacial interval. Graminoid-herb tundra suggests that central Beringia had a cold, arid climate from ???30,000 to 15,000 14C yr B.P. Between 15,000 and 13,000 14C yr B.P., birch shrub-Ericales-sedge-moss tundra began to spread rapidly across the land bridge and Alaska. This major vegetation change suggests moister, warmer summer climates and deeper winter snows. A brief invasion of Populus (poplar, aspen) occurred ca. 11,000-9500 14C yr B.P., overlapping with the Younger Dryas interval of dry, cooler(?) climate. During the latest Wisconsin to middle Holocene the Bering land bridge was flooded by rising seas. Alder shrubs (Alnus crispa) colonized the St. Michael Island area ca. 8000 14C yr B.P. Boreal forests dominated by spruce (Picea) spread from interior Alaska into the eastern Norton Sound area in middle Holocene time, but have not spread as far west as St. Michael Island. ?? 2003 University of Washington. Published by Elsevier Inc. All rights reserved.

  8. Optimization of Magnet Arrangement in Double-Layer Interior Permanent-Magnet Motors

    NASA Astrophysics Data System (ADS)

    Yamazaki, Katsumi; Kitayuguchi, Kazuya

    The arrangement of permanent magnets in double-layer interior permanent-magnet motors is optimized for variable-speed applications. First, the arrangement of magnets is decided by automatic optimization. Next, the superiority of the optimized motor is discussed by the d- and q-axis equivalent circuits that consider the magnetic saturation of the rotor core. Finally, experimental verification is carried out by using a prototype motor. It is confirmed that the maximum torque of the optimized motor under both low speed and high speed conditions are higher than those of conventional motors because of relatively large q-axis inductance and small d-axis inductance.

  9. Origin and thermal evolution of Mars

    NASA Technical Reports Server (NTRS)

    Schubert, G.; Solomon, Sean C.; Turcotte, D. L.; Drake, M. J.; Sleep, N. H.

    1993-01-01

    The thermal evolution of Mars is governed by subsolidus mantle convection beneath a thick lithosphere. Models of the interior evolution are developed by parameterizing mantle convective heat transport in terms of mantle viscosity, the superadiabatic temperature rise across the mantle and mantle heat production. Geological, geophysical, and geochemical observations of the composition and structure of the interior and of the timing of major events in Martian evolution, such as global differentiation, atmospheric outgassing and the formation of the hemispherical dichotomy and Tharsis, are used to constrain the model computations. Isotope systematics of SNC meteorites suggest core formation essentially contemporaneously with the completion of accretion. Other aspects of this investigation are discussed.

  10. Potential MER Landing Site in Melas Chasma

    NASA Technical Reports Server (NTRS)

    Weitz, C. M.; Parker, Timothy J.; Anderson, F. Scott

    2001-01-01

    We have selected one area in Valles Marineris as a potential landing site for the Mars Exploration Rover (MER) mission. After 30 years of analyses, the formation of the Valles Marineris system of troughs and its associated deposits still remains an enigma. Understanding all aspects of the Valles Marineris would significantly contribute to deciphering the internal and external history of Mars. A landing site within Melas Chasma could provide insight into both the formation of Valles Marineris and the composition and origin of the interior layered deposits (ILDs). The ILDs have been proposed as: (1) sedimentary deposits formed in lakes mass wasted material from the walls; (3) remnants of the wall rock; (4) carbonate deposits; (5) aeolian deposits; and (6) volcanic. More recently, Malin and Edgett suggest that the fine-scale, rhythmic layering seen in the interior deposits, as well as other layered deposits in craters, supports a sedimentary origin. Because an understanding of the formation of Valles Marineris and its interior deposits is so important to deciphering the history of Mars, we have proposed a landing site for the MER mission on an exposure of interior deposits in western Melas Chasma. Either MER-A and MER-B could land at this same location.

  11. The sedimentology and dynamics of crater-affiliated wind streaks in western Arabia Terra, Mars and Patagonia, Argentina

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Tanaka, K.L.; Yamamoto, A.; Berman, D.C.; Zimbelman, J.R.; Kargel, J.S.; Sasaki, S.; Jinguo, Y.; Miyamoto, H.

    2010-01-01

    Wind streaks comprise recent aeolian deposits that have been extensively documented on Venus, Earth and Mars. Martian wind streaks are among the most abundant surface features on the planet and commonly extend from the downwind margins of impact craters. Previous studies of wind streaks emerging from crater interior deposits suggested that the mode of emplacement was primarily related to the deposition of silt-sized particles as these settled from plumes. We have performed geologic investigations of two wind streaks clusters; one situated in western Arabia Terra, a region in the northern hemisphere of Mars, and another in an analogous terrestrial site located in southern Patagonia, Argentina, where occurrences of wind streaks emanate from playas within maar craters. In both these regions we have identified bedforms in sedimentary deposits on crater floors, along wind-facing interior crater margins, and along wind streaks. These observations indicate that these deposits contain sand-sized particles and that sediment migration has occurred via saltation from crater interior deposits to wind streaks. In Arabia Terra and in Patagonia wind streaks initiate from crater floors that contain lithic and evaporitic sedimentary deposits, suggesting that the composition of wind streak source materials has played an important role in development. Spatial and topographic analyses suggest that regional clustering of wind streaks in the studied regions directly correlates to the areal density of craters with interior deposits, the degree of proximity of these deposits, and the craters' rim-to-floor depths. In addition, some (but not all) wind streaks within the studied clusters have propagated at comparable yearly (Earth years) rates. Extensive saltation is inferred to have been involved in its propagation based on the studied terrestrial wind streak that shows ripples and dunes on its surface and the Martian counterpart changes orientation toward the downslope direction where it extends into an impact crater. ?? 2009 Elsevier B.V.

  12. Structural and facies characterization of the Niobrara Formation in Goshen and Laramie counties, Wyoming

    NASA Astrophysics Data System (ADS)

    Kernan, Nicholas Devereux

    The Niobrara Formation is a fine-grained marine rock deposited in the Western Interior Seaway during the Late Cretaceous. It is composed of fossil-rich interlayered shale, marls, and chalks. Recent interest in the Niobrara has grown due to the advent of lateral drilling and multi-stage hydraulic fracturing. This technology allows operators to economically extract hydrocarbons from chalkier Niobrara facies. Yet two aspects of the Niobrara Formation have remained enigmatic. The first is the occurrence of abundant, randomly oriented, layer-bound, normal faults. The second is the large degree of vertical heterogeneity. This research aimed to increase understanding in both these aspects of the Niobrara Formation. Randomly oriented normal faults have been observed in Niobrara outcrops for nearly a hundred years. Recent high resolution 3D seismic in the Denver Basin has allowed investigators to interpret these faults as part of a polygonal fault system (PFS). PFS are layer bound extensional structures that typically occur in fine-grained marine sediments. Though their genesis and development is still poorly understood, their almost exclusive occurrence in fine-grained rocks indicates their origin is linked to lithology. Interpretation of a 3D seismic cube in Southeast Wyoming found a tier of polygonal faulting within the Greenhorn-Carlile formations and another tier of polygonal faulting within the Niobrara and Pierre formations. This research also found that underlying structural highs influence fault growth and geometries within both these tiers. Core data and thin sections best describe vertical heterogeneity in fine-grained rocks. This investigation interpreted core data and thin sections in a well in Southeast Wyoming and identified 10 different facies. Most of these facies fall within a carbonate/clay spectrum with clay-rich facies deposited during periods of lower sea level and carbonate-rich facies deposited during periods of higher sea level. Because the average operator will typically have little core but abundant well logs, this investigation used three different methods of describing facies variability with logs. Facies interpreted with these methods are referred to as electrofacies. First, a conventional interpretation of Niobrara sub-units was done using gamma ray and resistivity logs. Then a cluster analysis was conducted on an extensive petrophysical log suite. Finally, a neural network was trained with the previous core interpretation so that it learned to identify facies from logs. The research found that when little core is available a cluster analysis method can capture significant amounts of vertical heterogeneity within the Niobrara Formation. But if core is available then a neural network method provides more meaningful and higher resolution interpretations.

  13. Late Wisconsinan glaciation and postglacial relative sea-level change on western Banks Island, Canadian Arctic Archipelago

    NASA Astrophysics Data System (ADS)

    Lakeman, Thomas R.; England, John H.

    2013-07-01

    The study revises the maximum extent of the northwest Laurentide Ice Sheet (LIS) in the western Canadian Arctic Archipelago (CAA) during the last glaciation and documents subsequent ice sheet retreat and glacioisostatic adjustments across western Banks Island. New geomorphological mapping and maximum-limiting radiocarbon ages indicate that the northwest LIS inundated western Banks Island after ~ 31 14C ka BP and reached a terminal ice margin west of the present coastline. The onset of deglaciation and the age of the marine limit (22-40 m asl) are unresolved. Ice sheet retreat across western Banks Island was characterized by the withdrawal of a thin, cold-based ice margin that reached the central interior of the island by ~ 14 cal ka BP. The elevation of the marine limit is greater than previously recognized and consistent with greater glacioisostatic crustal unloading by a more expansive LIS. These results complement emerging bathymetric observations from the Arctic Ocean, which indicate glacial erosion during the Last Glacial Maximum (LGM) to depths of up to 450 m.

  14. View of southeastern New York State

    NASA Image and Video Library

    1973-08-15

    SL3-87-299 (July-September 1973) --- A vertical view of southeastern New York State is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch Earth terrain camera) infrared photograph taken from the Skylab space station in Earth orbit. An 18-inch, 450mm lens and type 2443 infrared Ektachrome film was used. This picture covers the northern part of New Jersey, a part of northwestern Pennsylvania, and the western tip of Connecticut. The body of water is Long Island Sound. The wide Hudson River flows southward across a corner of the photograph. The New York City metropolitan area occupies part of the picture. Federal agencies participating with NASA on the EREP project are the Departments of Agriculture, Commerce, Interior, the Environmental Protection Agency and the Corps of Engineers. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

  15. Late Quaternary lake-level changes constrained by radiocarbon and stable isotope studies on sediment cores from Lake Titicaca, South America

    NASA Astrophysics Data System (ADS)

    Rowe, Harold D.; Guilderson, Thomas P.; Dunbar, Robert B.; Southon, John R.; Seltzer, Geoffrey O.; Mucciarone, David A.; Fritz, Sherilyn C.; Baker, Paul A.

    2003-09-01

    We present and compare AMS- 14C geochronologies for sediment cores recovered from Lake Titicaca, South America. Radiocarbon dates from three core sites constrain the timing of late Quaternary paleoenvironmental changes in the Central Andes and highlight the site-specific factors that limit the radiocarbon geochronometer. With the exception of mid-Holocene sediments, all cores are generally devoid of macrophyte fragments, thus bulk organic fractions are used to build core chronologies. Comparisons of radiocarbon results for chemically defined fractions (bulk decalcified, humate, humin) suggest that ages derived from all fractions are generally coherent in the post-13,500 yr BP time interval. In the pre-13,500 yr BP time interval, ages derived from humate extracts are significantly younger (300-7000 years) than ages from paired humin residues. Gross age incoherencies between paired humate and humin sub-fractions in pre-13,500 yr BP sediments from all core sites probably reflect the net downward migration of humates. Ages derived from bulk decalcified fractions at our shallow water (90 m) and deep water (230 m) core sites consistently fall between ages derived from humate and humin sub-fractions in the pre-13,500 yr BP interval, reflecting that the bulk decalcified fraction is predominantly a mixture of humate and humin sub-fractions. Bulk decalcified ages from the pre-13,500 yr BP interval at our intermediate depth core site (150 m) are consistently older than humate (youngest) and humin sub-fractions. This uniform, reproducible pattern can be explained by the mobilization of a relatively older organic sub-fraction during and after the re-acidification step following the alkaline treatment of the bulk sediment. The inferred existence of this 'alkali-mobile, acid-soluble' sub-fraction implies a different depositional/post-depositional history that is potentially associated with a difference in source material. While internally consistent geochronologies can be developed for the Lake Titicaca sequence using different organic fractions, mobile organic sub-fractions and fractions containing mobile sub-fractions should generally be avoided in geochronology studies. Consequently, we believe humin and/or bulk decalcified ages provide the most consistent chronologies for the post-13,500 yr BP interval, and humin ages provide the most representative ages for sedimentation prior to 13,500 yr BP interval. Using the age model derived from the deep water core site and a previously published isotope-based lake-level reconstruction, we present a qualitative record of lake level in the context of several ice-core records from the western hemisphere. We find the latest Pleistocene lake-level response to changing insolation began during or just prior to the Bølling/Allerød period. Using the isotope-based lake-level reconstruction, we also find the 85-m drop in lake level that occurred during the mid-Holocene was synchronous with an increase in the variability of ice-core δ18O from a nearby icecap, but was not reflected in any of the polar ice-core records recovered from the interior of Antarctica and Greenland.

  16. Value Focused Thinking for Nation Building in Afghanistan: A Regional Perspective

    DTIC Science & Technology

    2012-03-01

    Force Instructions/ Orders). Using existing policy documents is known as the “gold standard” and yields the most defendable final decisions. They are...Integrated Gap , characterized by unstable leadership and absence from international trade. The Core can be sub-divided into Old Core (North America...Western Europe, Japan, and Australia) and New Core (China, India, South Africa, Brazil, Argentina, Chile and Russia). The Disconnected Gap includes the

  17. Studies of pre-Selma Cretaceous core samples from the outcrop area in western Alabama

    USGS Publications Warehouse

    Monroe, Watson Hiner; Bergenback, Richard E.; Sohl, Norman F.; Applin, Esther R.; Leopold, Estella B.; Pakiser, Helen M.; Conant, Louis C.

    1964-01-01

    Quarter-cuts of the cores belonging to the U.S. National Museum have been deposited on indefinite loan with the Alabama Geological Survey at University, Ala., and with the Shell Oil Co. at Jackson, Miss. They are available there for inspection and study.

  18. Source identification of western Oregon Douglas-fir wood cores using mass spectrometry and random forest classification.

    PubMed

    Finch, Kristen; Espinoza, Edgard; Jones, F Andrew; Cronn, Richard

    2017-05-01

    We investigated whether wood metabolite profiles from direct analysis in real time (time-of-flight) mass spectrometry (DART-TOFMS) could be used to determine the geographic origin of Douglas-fir wood cores originating from two regions in western Oregon, USA. Three annual ring mass spectra were obtained from 188 adult Douglas-fir trees, and these were analyzed using random forest models to determine whether samples could be classified to geographic origin, growth year, or growth year and geographic origin. Specific wood molecules that contributed to geographic discrimination were identified. Douglas-fir mass spectra could be differentiated into two geographic classes with an accuracy between 70% and 76%. Classification models could not accurately classify sample mass spectra based on growth year. Thirty-two molecules were identified as key for classifying western Oregon Douglas-fir wood cores to geographic origin. DART-TOFMS is capable of detecting minute but regionally informative differences in wood molecules over a small geographic scale, and these differences made it possible to predict the geographic origin of Douglas-fir wood with moderate accuracy. Studies involving DART-TOFMS, alone and in combination with other technologies, will be relevant for identifying the geographic origin of illegally harvested wood.

  19. Geophysical Monitoring Station (GEMS)

    NASA Astrophysics Data System (ADS)

    Banerdt, B.; Dehant, V. M.; Lognonne, P.; Smrekar, S. E.; Spohn, T.; GEMS Mission Team

    2011-12-01

    GEMS (GEophysical Monitoring Station) is one of three missions undergoing Phase A development for possible selection by NASA's Discovery Program. If selected, GEMS will perform the first comprehensive surface-based geophysical investigation of Mars, filling a longstanding gap in the scientific exploration of the solar system. It will illuminate the fundamental processes of terrestrial planet formation and evolution, providing unique and critical information about the initial accretion of the planet, the formation and differentiation of the core and crust, and the subsequent evolution of the interior. The scientific goals of GEMS are to understand the formation and evolution of terrestrial planets through investigation of the interior structure and processes of Mars and to determine its present level of tectonic activity and impact flux. A straightforward set of scientific objectives address these goals: 1) Determine the size, composition and physical state of the core; 2) Determine the thickness and structure of the crust; 3) Determine the composition and structure of the mantle; 4) Determine the thermal state of the interior; 5) Measure the rate and distribution of internal seismic activity; and 6) Measure the rate of impacts on the surface. To accomplish these objectives, GEMS carries a tightly-focused payload consisting of 3 investigations: 1) SEIS, a 6-component, very-broad-band seismometer, with careful thermal compensation/control and a sensitivity comparable to the best terrestrial instruments across a frequency range of 1 mHz to 50 Hz; 2) HP3 (Heat Flow and Physical Properties Package), an instrumented self-penetrating mole system that trails a string of temperature sensors to measure the thermal gradient and conductivity of the upper several meters, and thus the planetary heat flux; and 3) RISE (Rotation and Interior Structure Experiment), which would use the spacecraft X-band communication system to provide precision tracking for planetary dynamical studies. The two instruments are moved from the lander deck to the martian surface by an Instrument Deployment Arm, with an appropriate location identified using an Instrument Deployment Camera. In order to ensure low risk within the tight Discovery cost limits, GEMS reuses the successful Lockheed Martin Phoenix spacecraft design, with a cruise and EDL system that has demonstrated capability for safe landing on Mars with well-understood costs. To take full advantage of this approach, all science requirements (such as instrument mass and power, landing site, and downlinked data volume) strictly conform to existing, demonstrated capabilities of the spacecraft and mission system. It is widely believed that multiple landers making simultaneous measurements (a network) are required to address the objectives for understanding terrestrial planet interiors. Nonetheless, comprehensive measurements from a single geophysical station are extremely valuable, because observations constraining the structure and processes of the deep interior of Mars are virtually nonexistent. GEMS would utilize sophisticated analysis techniques specific to single-station measurements to determine crustal thickness, mantle structure, core state and size, and heat flow, providing our first real look deep beneath the surface of Mars.

  20. Vulnerability of riparian obligate species to the interactive effect of fire, climate and hydrological change

    Treesearch

    Megan M. Friggens; Rachel Loehman; Lisa Holsinger; Deborah Finch

    2014-01-01

    Climate change is expected to have multiple direct and indirect impacts on ecosystems in the interior western U.S. (Christensen et al., 2007; IPCC 2013). Global climate predictions for the Southwest include higher temperatures, more variable rainfall, and more drought periods, which will likely exacerbate the ongoing issues relating to wildfire and water allocation in...

  1. Log export restrictions of the Western states and British Columbia.

    Treesearch

    J.A. Hines

    1987-01-01

    The export of unprocessed timber is restricted from lands managed by the Forest Service, U.S. Department of Agriculture, and the Bureau of Land Management, U.S. Department of the Interior, in the West. In addition, the Forest Service and the Bureau of Land Management have implemented regulations to ensure that Federal timber is not substituted for private timber. The...

  2. Assessment and response to bark beetle outbreaks in the Rocky Mountain area

    Treesearch

    Safiya Samman; Jesse Logan

    2000-01-01

    Bark beetles act as "agents of change" within the conifer forests of the Rocky Mountain area. They play a critical role in the development, senescence, and rebirth of Western forests. Bark beetle-caused tree mortality can be extensive, covering thousands of acres. This report is the Forest Service response to a Congressional direction in the FY2000 Interior...

  3. Modeling potential outcomes of fire and fuel management scenarios on the structure of forested habitats in northeast Oregon, USA.

    Treesearch

    B.C. Wales; L.H. Suring; M.A. Hemstrom

    2007-01-01

    Thinning and prescribed fire are being used extensively across the interior Western United States to reduce the risk of large, severe wildfires. However, the full ecological consequences of implementing these management practices on the landscape have not been completely evaluated. We projected future vegetation trends resulting from four management scenarios and...

  4. Creating a Strong, Healthy Community: Ella B. Vernetti School, Koyukuk. Case Study.

    ERIC Educational Resources Information Center

    Leonard, Beth

    As part of a larger study of systemic educational reform in rural Alaska, this case study examines implementation of the Alaska Onward to Excellence (AOTE) process in Koyukuk, a small Athabascan village on the Yukon River in western interior Alaska. The village has a K-10 school with an enrollment of 19-41 students during the study period. A…

  5. Modeling and predicting vegetation response of western USA grasslands, shrublands, and deserts to climate change (Chapter 1)

    Treesearch

    Megan M. Friggens; Marcus V. Warwell; Jeanne C. Chambers; Stanley G. Kitchen

    2012-01-01

    Experimental research and species distribution modeling predict large changes in the distributions of species and vegetation types in the Interior West due to climate change. Species’ responses will depend not only on their physiological tolerances but also on their phenology, establishment properties, biotic interactions, and capacity to evolve and migrate. Because...

  6. Soil carbon in arid and semiarid forest ecosystems [Chapter 18

    Treesearch

    Daniel G. Neary; Steven T. Overby; Stephen C. Hart

    2002-01-01

    Forests of the semiarid and arid zones of the interior western United States (US) are some of the most unique in North America. They occupy 11 to 34% of the landscape at mostly higher elevations (USDA Forest Service, 1981). These forests are characterized by a high diversity of flora, fauna, climates, elevations, soils, geology, hydrology, and productivity. Within the...

  7. Decline of aspen (Populus tremuloides) in the Interior West [Abstract 1

    Treesearch

    Dale L. Bartos; Robert B Campbell

    1997-01-01

    Western aspen forests are unique because they reproduce primarily by suckering from the parent root system. Generally a disturbance or die back is necessary to stimulate regeneration of the stands. Unlike other tree species, if aspen stands are lost from the landscape, generally they will not return through natural processes. If current conditions continue (e.g., lack...

  8. An economic assessment of mountain pine beetle timber salvage in the west

    Treesearch

    Jeffrey P. Prestemon; Karen L. Abt; Kevin M. Potter; Frank H. Koch

    2013-01-01

    The mountain pine beetle has killed lodgepole pine and other species of pines in the western United States in an ongoing epidemic. The most heavily affected states are in the interior West: Colorado, Idaho, Montana, and Wyoming, with smaller losses elsewhere. Timber salvage is one response to the epidemic, which could generate revenues for affected landowners and...

  9. Detail of wharf A timber framing, showing piers and pier ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of wharf A timber framing, showing piers and pier caps or plates stepping down for a sloped launching deck, now built-up for a flat deck, interior of sheet steel bulkhead is visible at wharf edge - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

  10. 76 FR 75539 - Intent To Prepare an Environmental Impact Statement for the Central Everglades Planning Project...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ... the Federal government, in partnership with the State of Florida, to embark upon a multi-decade, multi... Spreader Canal Western Project. All of these CERP projects utilize lands that were acquired by the State... flows to the interior of the system will not cause adverse effects. The next step for implementation of...

  11. Is the western United States running out of trees?

    Treesearch

    J. Shaw; J. Long

    2014-01-01

    During the past 2 decades, the forests of the Interior West of the United States have been impacted by drought, insects, disease, and fire. When considered over periods of 5-10 years, many forest types have experienced periods of negative net growth, meaning that mortality exceeded gross growth at the population scale. While many of these changes have been attributed...

  12. Flexural subsidence and basement tectonics of the Cretaceous Western Interior basin, United States

    NASA Astrophysics Data System (ADS)

    Pang, Ming; Nummedal, Dag

    1995-02-01

    The flexural subsidence history recorded in Cenomanian to early Campanian (97 to 80 Ma) strata in the Cretaceous U.S. Western Interior basin was studied with two-dimensional flexural backstripping techniques. Results indicate that the flexural subsidence resulting from thrust loading was superimposed on epeirogenic subsidence in the foreland basin. The flexural component exhibits significant spatial and temporal variations along both the strike and dip relative to the Sevier thrust belt. The greatest cumulative subsidence occurred in southwestern Wyoming and northern Utah. Concurrent subsidence in northwestern Montana and southern Utah was insignificant. Temporal trends in subsidence also show a distinct regional pattern. From the Cenomanian to late Turonian (97 to 90 Ma), subsidence rates were high in Utah and much lower in Wyoming and Montana. In contrast, during the Coniacian and Santonian (90 to 85 Ma) subsidence accelerated rapidly in Wyoming, increased slightly in Montana, and decreased in Utah. We suggest that these spatially and temporally varying subsidence patterns reflect the interplay of several geodynamic factors, including: (1) temporal and spatial variation in emplacement of the thrust loads, (2) segmentation of the basement into adjacent blocks with different rheological properties, (3) reactivation of basement fault trends, and (4) regional dynamic topographic effects.

  13. Further Constraints and Uncertainties on the Deep Seismic Structure of the Moon

    NASA Technical Reports Server (NTRS)

    Lin, Pei-Ying Patty; Weber, Renee C.; Garnero, Ed J.; Schmerr, Nicholas C.

    2011-01-01

    The Apollo Passive Seismic Experiment (APSE) consisted of four 3-component seismometers deployed between 1969 and 1972, that continuously recorded lunar ground motion until late 1977. The APSE data provide a unique opportunity for investigating the interior of a planet other than Earth, generating the most direct constraints on the elastic structure, and hence the thermal and compositional evolution of the Moon. Owing to the lack of far side moonquakes, past seismic models of the lunar interior were unable to constrain the lowermost 500 km of the interior. Recently, array methodologies aimed at detecting deep lunar seismic reflections found evidence for a lunar core, providing an elastic model of the deepest lunar interior consistent with geodetic parameters. Here we study the uncertainties in these models associated with the double array stacking of deep moonquakes for imaging deep reflectors in the Moon. We investigate the dependency of the array stacking results on a suite of parameters, including amplitude normalization assumptions, polarization filters, assumed velocity structure, and seismic phases that interfere with our desired target phases. These efforts are facilitated by the generation of synthetic seismograms at high frequencies (approx. 1Hz), allowing us to directly study the trade-offs between different parameters. We also investigate expected amplitudes of deep reflections relative to direct P and S arrivals, including predictions from arbitrarily oriented focal mechanisms in our synthetics. Results from separate versus combined station stacking help to establish the robustness of stacks. Synthetics for every path geometry of data were processed identically to that done with data. Different experiments were aimed at examining various processing assumptions, such as adding random noise to synthetics and mixing 3 components to some degree. The principal stacked energy peaks put forth in recent work persist, but their amplitude (which maps into reflector impedance contrast) and timing (which maps into reflector depth) depend on factors that are not well constrained -- most notably, the velocity structure of the overlying lunar interior. Thus, while evidence for the lunar core remains strong, the depths of imaged reflectors have associated uncertainties that will require new seismic data and observations to constrain. These results strongly advocate further investigations on the Moon to better resolve the interior (e.g., Selene missions), for the Moon apparently has a rich history of construction and evolution that is inextricably tied to that of Earth.

  14. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA

    DOE PAGES

    Stewart, Joseph A. E.; Wright, David H.; Heckman, Katherine A.

    2017-08-30

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species’ core habitat has been lacking. Here in this paper, we report the extirpation of the American pika (Ochotona princeps), a temperature-sensitive small mammal, from a 165-km 2 area located within its core habitat in California’s Sierra Nevada mountains. While sites surrounding the area still maintain pikas, radiocarbon analyses of pika fecal pellets recovered within this area indicate that former patch occupancymore » ranges from before 1955, the beginning of the atmospheric spike in radiocarbon associated with above ground atomic bomb testing, to c. 1991. Despite an abundance of suitable rocky habitat climate warming appears to have precipitated their demise. Weather station data reveal a 1.9°C rise in local temperature and a significant decline in snowpack over the period of record, 1910–2015, pushing pika habitat into increasingly tenuous climate conditions during the period of extirpation. This is among the first accounts of an apparently climate-mediated, modern extirpation of a species from an interior portion of its geographic distribution, resulting in habitat fragmentation, and is the largest area yet reported for a modern-era pika extirpation. Our finding provides empirical support to model projections, indicating that even core areas of species habitat are vulnerable to climate change within a timeframe of decades.« less

  15. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA

    PubMed Central

    Wright, David H.; Heckman, Katherine A.

    2017-01-01

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species’ core habitat has been lacking. Here, we report the extirpation of the American pika (Ochotona princeps), a temperature-sensitive small mammal, from a 165-km2 area located within its core habitat in California’s Sierra Nevada mountains. While sites surrounding the area still maintain pikas, radiocarbon analyses of pika fecal pellets recovered within this area indicate that former patch occupancy ranges from before 1955, the beginning of the atmospheric spike in radiocarbon associated with above ground atomic bomb testing, to c. 1991. Despite an abundance of suitable rocky habitat climate warming appears to have precipitated their demise. Weather station data reveal a 1.9°C rise in local temperature and a significant decline in snowpack over the period of record, 1910–2015, pushing pika habitat into increasingly tenuous climate conditions during the period of extirpation. This is among the first accounts of an apparently climate-mediated, modern extirpation of a species from an interior portion of its geographic distribution, resulting in habitat fragmentation, and is the largest area yet reported for a modern-era pika extirpation. Our finding provides empirical support to model projections, indicating that even core areas of species habitat are vulnerable to climate change within a timeframe of decades. PMID:28854268

  16. Reduced gas accretion on super-Earths and ice giants

    NASA Astrophysics Data System (ADS)

    Lambrechts, M.; Lega, E.

    2017-10-01

    A large fraction of giant planets have gaseous envelopes that are limited to about 10% of their total mass budget. Such planets are present in the solar system (Uranus, Neptune) and are frequently observed in short periods around other stars (the so-called super-Earths). In contrast to these observations, theoretical calculations based on the evolution of hydrostatic envelopes argue that such low-mass envelopes cannot be maintained around cores exceeding five Earth masses. Instead, under nominal disk conditions, these planets would acquire massive envelopes through runaway gas accretion within the lifetime of the protoplanetary disk. In this work we show that planetary envelopes are not in hydrostatic balance, which slows down envelope growth. A series of 3D global, radiative hydrodynamical simulations reveal a steady-state gas flow, which enters through the poles and exits in the disk midplane. Gas is pushed through the outer envelope in about ten orbital timescales. In regions of the disk that are not significantly dust-depleted, envelope accretion onto cores of about five Earth masses can get stalled as the gas flow enters the deep interior. Accreted solids sublimate deep in the convective interior, but small opacity-providing grains are trapped in the flow and do not settle, which further prevents rapid envelope accretion. The transition to runaway gas accretion can however be reached when cores grow larger than typical super-Earths, beyond 15 Earth masses, and preferably when disk opacities are below κ = 1 cm2/g. These findings offer an explanation for the typical low-mass envelopes around the cores of super-Earths.

  17. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stewart, Joseph A. E.; Wright, David H.; Heckman, Katherine A.

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species’ core habitat has been lacking. Here in this paper, we report the extirpation of the American pika (Ochotona princeps), a temperature-sensitive small mammal, from a 165-km 2 area located within its core habitat in California’s Sierra Nevada mountains. While sites surrounding the area still maintain pikas, radiocarbon analyses of pika fecal pellets recovered within this area indicate that former patch occupancymore » ranges from before 1955, the beginning of the atmospheric spike in radiocarbon associated with above ground atomic bomb testing, to c. 1991. Despite an abundance of suitable rocky habitat climate warming appears to have precipitated their demise. Weather station data reveal a 1.9°C rise in local temperature and a significant decline in snowpack over the period of record, 1910–2015, pushing pika habitat into increasingly tenuous climate conditions during the period of extirpation. This is among the first accounts of an apparently climate-mediated, modern extirpation of a species from an interior portion of its geographic distribution, resulting in habitat fragmentation, and is the largest area yet reported for a modern-era pika extirpation. Our finding provides empirical support to model projections, indicating that even core areas of species habitat are vulnerable to climate change within a timeframe of decades.« less

  18. Aggradation of gravels in tidally influenced fluvial systems: Upper Albian (Lower Cretaceous) on the cratonic margin of the North American Western Interior foreland basin

    USGS Publications Warehouse

    Brenner, Richard L.; Ludvigson, Greg A.; Witzke, B.L.; Phillips, P.L.; White, T.S.; Ufnar, David F.; Gonzalez, Luis A.; Joeckel, R.M.; Goettemoeller, A.; Shirk, B.R.

    2003-01-01

    Alluvial conglomerates were widely distributed around the margin of the Early Cretaceous North American Cretaceous Western Interior Seaway (KWIS). Conglomerates, sandstones, and lesser amounts of mudstones of the upper Albian Nishnabotna Member of the Dakota Formation were deposited as fill-in valleys that were incised up to 80 m into upper Paleozoic strata. These paleovalleys extended southwestward across present-day northwestern Iowa into eastern Nebraska. Conglomerate samples from four localities in western Iowa and eastern Nebraska consist mostly of polycrystalline quartz with lesser amounts of microcrystalline (mostly chert), and monocrystalline quartz. Previous studies discovered that some chert pebbles contain Ordovician-Pennsylvanian invertebrate fossils. The chert clasts analyzed in this study were consistent with these findings. In addition, we found that non-chert clasts consist of metaquartzite, strained monocrystalline quartz and 'vein' quartz from probable Proterozic sources, indicating that parts of the fluvial system's sediment load must have travelled distances of 400-1200 km. The relative tectonic stability of this subcontinent dictated that stream gradients were relatively low with estimates ranging from 0.3 to 0.6 m/km. Considering the complex sedimentologic relationships that must have been involved, the ability of low-gradient easterly-sourced rivers to entrain gravel clasts was primarily a function of paleodischarge rather than a function of steep gradients. Oxygen isotopic evidence from Albian sphaerosiderite-bearing paleosols in the Dakota Formation and correlative units from Kansas to Alaska suggest that mid-latitude continental rainfall in the Albian was perhaps twice that of the modern climate system. Hydrologic fluxes may have been related to wet-dry climatic cycles on decade or longer scales that could account for the required water supply flux. Regardless of temporal scale, gravels were transported during 'high-energy' pulses, under humid climatic conditions in large catchment areas. An overall rising sea level during the late Albian created accommodation space for the gravelly lithofacies equivalent to the Kiowa-Skull Creek rocks. As Western Interior sea level rose, regional stream gradients were reduced, resulting in regional fluvial aggradation. The conglomeratic lower parts of the Nishnabotna Member of the Dakota Formation formed the transgressive systems tract within an upper Albian sequence that is defined by two unconformities that can be traced from marine Kiowa strata in western Kansas northeastward into western Iowa (Brenner et al., 2000). Mud-draped cross-bedded sandstone bodies, laminated mudstone intervals, and vertical burrows in the lower strata of the Nishnabotna Member indicate that estuarine conditions existed at the mouths of the river system, and tidal effects were transmitted at least 200 km inland from the interpreted late Albian coast. These observations suggest that estuarine conditions stepped up the incised valleys as fluvial sediments aggraded in response to regional transgression that continued through the Late Albian. ?? 2003 Elsevier Ltd. All rights reserved.

  19. A core set of microsatellite markers for Western Corn Rootworm (Coleoptera: Chrysomelidae) population genetics studies

    EPA Science Inventory

    Interest in the ecological and population genetics of the western corn rootworm, Diabrotica virgifera virgifera LeConte, has grown rapidly in the last few years in North America and Europe. This interest is a result of a number of converging issues related to increasing difficult...

  20. The Offerings of Fringe Figures and Migrants

    ERIC Educational Resources Information Center

    Engels-Schwarzpaul, A.-Chr.

    2015-01-01

    "The Western tradition", as passe-partout, includes fringe figures, émigrés and migrants. Rather than looking to resources at the core of the Western tradition to overcome its own blindnesses, I am more interested in its gaps and peripheries, where other thoughts and renegade knowledges take hold. It is in the contact zones with…

  1. P- T- t constraints on the development of the Doi Inthanon metamorphic core complex domain and implications for the evolution of the western gneiss belt, northern Thailand

    NASA Astrophysics Data System (ADS)

    Macdonald, A. S.; Barr, S. M.; Miller, B. V.; Reynolds, P. H.; Rhodes, B. P.; Yokart, B.

    2010-01-01

    The western gneiss belt in northern Thailand is exposed within two overlapping Cenozoic structural domains: the extensional Doi Inthanon metamorphic core complex domain located west of the Chiang Mai basin, and the Mae Ping strike-slip fault domain located west of the Tak batholith. New P- T estimates and U-Pb and 40Ar/ 39Ar age determinations from the Doi Inthanon domain show that the gneiss there records a complex multi-stage history that can be represented by a clockwise P- T- t path. U-Pb zircon and titanite dating of mylonitic calc-silicate gneiss from the Mae Wang area of the complex indicates that the paragneissic sequence experienced high-grade, medium-pressure metamorphism (M1) in the Late Triassic - Early Jurassic (ca. 210 Ma), in good agreement with previously determined zircon ages from the underlying core orthogneiss exposed on Doi Inthanon. Late Cretaceous monazite ages of 84 and 72 Ma reported previously from the core orthogneiss are attributed to a thermal overprint (M2) to upper-amphibolite facies in the sillimanite field. U-Pb zircon and monazite dating of granitic mylonite from the Doi Suthep area of the complex provides an upper age limit of 40 Ma (Late Eocene) for the early stage(s) of development of the actual core complex, by initially ductile, low-angle extensional shearing under lower amphibolite-facies conditions (M3), accompanied by near-isothermal diapiric rise and decompression melting. 40Ar/ 39Ar laserprobe dating of muscovite from both Doi Suthep and Doi Inthanon provided Miocene ages of ca. 26-15 Ma, representing cooling through the ca. 350 °C isotherm and marking late-stage development of the core complex by detachment faulting of the cover rocks and isostatic uplift of the sheared core zone and mantling gneisses in the footwall. Similarities in the thermochronology of high-grade gneisses exposed in the core complex and shear zone domains in the western gneiss belt of northern Thailand (and also in northern Vietnam, Laos, Yunnan, and central Myanmar) suggest a complex regional response to indentation of Southeast Asia by India.

  2. Seismic imaging of extended crust with emphasis on the western United States

    USGS Publications Warehouse

    McCarthy, J.; Thompson, G.A.

    1988-01-01

    Understanding of the crust has improved dramatically following the application of seismic reflection and refraction techniques to studies of the deep crust. This is particularly true in areas where the last tectonic event was extensional, such as the Basin and Range province of the western United States and much of western Europe. In these regions, a characteristic reflective pattern has emerged, whereby the lower crust is highly reflective and the upper crust and upper mantle are either poorly reflective or strikingly nonreflective. In the metamorphic-core-complex belt in the western United States, where extension can be as much as an order of magnitude greater than in the more classic continental rift zones, the lower crustal reflectivity thickens and rises, yielding a picture of a crust that is reflective throughout. If metamorphic core complexes are representative of extended continental crust world-wide, then these results suggest that magmatism and ductile flow have also contributed to the evolution of the middle and lower crust in many other areas around the world. -from Authors

  3. [Factional disputes on the retention or abolition of traditional Chinese medicine within the National Government].

    PubMed

    Hao, Xian-zhong; Zhu, De-pei

    2008-07-01

    The disputes between Western and traditional Chinese medicine (TCM) started at the turn of late Qing Dynasty to early Republican China, intensified in the period of construction of National Government at Nanking, lasting for several years. The scope of dispute also extended from the initial medical area to the mass media, and even to the government interior factions. The form of the combat also changed from the debates of original scientific theory to the confrontation of political ideology. It was the government interior factional disputes which caused "the case of abolition of the traditional Chinese medicine" to abort objectively, with the difficult advent of the regulations which saved TCM, to certain degree, from vanishing.

  4. InSight Launch

    NASA Image and Video Library

    2018-05-05

    The NASA InSight spacecraft launches onboard a United Launch Alliance Atlas-V rocket, Saturday, May 5, 2018, from Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  5. Ingestible Thermometer Pill Aids Athletes in Beating the Heat

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Developed by Goddard Space Flight Center and the Johns Hopkins University Applied Physics Laboratory to monitor the core body temperature of astronauts during space flight, the ingestible "thermometer pill" has a silicone-coated exterior, with a microbattery, a quartz crystal temperature sensor, a space-aged telemetry system, and microminiaturized circuitry on the interior.

  6. Hydro-ball in-core instrumentation system and method of operation

    DOEpatents

    Tower, Stephen N.; Veronesi, Luciano; Braun, Howard E.

    1990-01-01

    A hydro-ball in-core instrumentation system employs detector strings each comprising a wire having radiation sensitive balls affixed diametrically at spaced positions therealong and opposite tip ends of which are transportable by fluid drag through interior passageways. In the passageways primary coolant is caused to flow selectively in first and second opposite directions for transporting the detector strings from stored positions in an exterior chamber to inserted positions within the instrumentation thimbles of the fuel rod assemblies of a pressure vessel, and for return. The coolant pressure within the detector passageways is the same as that within the vessel; face contact, disconnectable joints between sections of the interior passageways within the vessel facilitate assembly and disassembly of the vessel for refueling and routine maintenance operations. The detector strings may pass through a very short bend radius thereby minimizing space requirements for the connections of the instrumentation system to the vessel and concomitantly the vessel containment structure. Improved radiation mapping and a significant reduction in potential exposure of personnel to radiation are provided. Both top head and bottom head penetration embodiments are disclosed.

  7. Structure and evolution of Uranus and Neptune

    NASA Technical Reports Server (NTRS)

    Hubbard, W. B.; Macfarlane, J. J.

    1980-01-01

    Three-layer interior models of Uranus and Neptune with central rocky cores, mantles of water, methane, and ammonia (the 'ices'), and outer envelopes primarily composed of hydrogen and helium are presented. The models incorporate a new H2O equation of state based on experimental data which is considerably 'softer' than previous H2O equations of state. Corrections for interior temperatures approximately 5000 K are included in the models, and the thermal evolution of both planets is investigated using recent heat flow measurements. It is found that the evolutionary considerations are consistent with gravitational field data in supporting models with approximately solar abundances of 'ice' and 'rock'. Evolutionary considerations indicate that initial temperatures and luminosities for Uranus and Neptune were not substantially higher than the present value. Both planets apparently have relatively small approximately 1-2 earth masses) hydrogen-helium envelopes, with Neptune's envelope smaller than Uranus'. A monotonic trend is evident among the Jovian planets: all have central rock-ice cores of approximately 15 earth masses, but with hydrogen-helium envelopes which decrease in mass from Jupiter to Saturn to Uranus to Neptune.

  8. Comparison of the performance of concrete-filled steel tubular and hollow steel diagrid buildings

    NASA Astrophysics Data System (ADS)

    Peter, Minu Ann; S, Sajith A.; Nagarajan, Praveen

    2018-03-01

    In the recent construction scenario, diagrid structures are becoming a popular high-rise building structural system. Diagrid structures consist of diagonals in the perimeter and an interior core. The corner and interior vertical columns are not required due to the structural efficiency of diagrid structural systems. Steel and concrete are commonly used material for diagrid. An alternate material for diagrid is concrete-filled steel tube (CFST). CFST incorporates the advantages of both steel and concrete. In CFST, the inward buckling of the steel tube is effectively prevented by the filled concrete. The compressive strength of concrete increases due to the tri-axial state of stress in concrete induced by the steel tube. The longitudinal as well as lateral reinforcement to the concrete core is also provided by the steel tube. This paper compares the performance of CFST and steel diagrid buildings using linear static analysis. For this purpose, a 12 storey and 36 storey building are analysed using finite element method and CFST diagrid building is found to perform better.

  9. Feast to famine: Sediment supply control on Laramide basin fill

    NASA Astrophysics Data System (ADS)

    Carroll, Alan R.; Chetel, Lauren M.; Elliot Smith, M.

    2006-03-01

    Erosion of Laramide-style uplifts in the western United States exerted an important first-order influence on Paleogene sedimentation by controlling sediment supply rates to adjacent closed basins. During the latest Cretaceous through Paleocene, these uplifts exposed thick intervals of mud-rich Upper Cretaceous foreland basin fill, which was quickly eroded and redeposited. Cretaceous sedimentary lithologies dominate Paleocene conglomerate clast compositions, and the volume of eroded foreland basin strata is approximately twice the volume of preserved Paleocene basin fill. As a result of this sediment oversupply, clastic alluvial and paludal facies dominate Paleocene strata, and are associated with relatively shallow and ephemeral freshwater lake facies. In contrast, large, long-lived, carbonate-producing lakes occupied several of the basins during the Eocene. Basement-derived clasts (granite, quartzite, and other metamorphic rocks) simultaneously became abundant in lower Eocene conglomerate. We propose that Eocene lakes developed primarily due to exposure of erosion-resistant lithologies within cores of Laramide uplifts. The resultant decrease in erosion rate starved adjacent basins of sediment, allowing the widespread and prolonged deposition of organic-rich lacustrine mudstone. These observations suggest that geomorphic evolution of the surrounding landscape should be considered as a potentially important influence on sedimentation in many other interior basins, in addition to more conventionally interpreted tectonic and climatic controls.

  10. Ground-truth collections at the MTI core sites

    NASA Astrophysics Data System (ADS)

    Garrett, Alfred J.; Kurzeja, Robert J.; Parker, Matthew J.; O'Steen, Byron L.; Pendergast, Malcolm M.; Villa-Aleman, Eliel

    2001-08-01

    The Savannah River Technology Center (SRTC) selected 13 sites across the continental US and one site in the western Pacific to serve as the primary or core site for collection of ground truth data for validation of MTI science algorithms. Imagery and ground truth data from several of these sites are presented in this paper. These sites are the Comanche Peak, Pilgrim and Turkey Point power plants, Ivanpah playas, Crater Lake, Stennis Space Center and the Tropical Western Pacific ARM site on the island of Nauru. Ground truth data includes water temperatures (bulk and skin), radiometric data, meteorological data and plant operating data. The organizations that manage these sites assist SRTC with its ground truth data collections and also give the MTI project a variety of ground truth measurements that they make for their own purposes. Collectively, the ground truth data from the 14 core sites constitute a comprehensive database for science algorithm validation.

  11. Preparation of ZnS@In2S3 Core@shell Composite for Enhanced Photocatalytic Degradation of Gaseous o-Dichlorobenzene under Visible Light.

    PubMed

    Liu, Baojun; Hu, Xia; Li, Xinyong; Li, Ying; Chen, Chang; Lam, Kwok-Ho

    2017-11-27

    In this study, novel ZnS@In 2 S 3 core@shell hollow nanospheres were fabricated by a facile refluxing method for the first time, and the formation mechanism of hollow structure with interior architecture was discussed based on ion-exchange Ostwald ripening. As the photocatalytic material for degradation of gaseous o-Dichlorobenzene (o-DCB), the as-synthesized core@shell hollow nanospheres were found to show significantly enhanced catalytic performance for effective separation of photo-generated charges. Moreover, the mechanisms of enhanced activity were elucidated by band alignment and unique configuration. Such photocatalyst would meet the demands for the control of persistent organic pollutant (POPs) in the atmospheric environment.

  12. Carbon from Crust to Core: A history of deep carbon science

    NASA Astrophysics Data System (ADS)

    Mitton, Simon

    2017-04-01

    As an academic historian of science, I am writing a history of the discovery of the interior workings of our dynamic planet. I am preparing a book, titled Carbon from Crust to Core: A Chronicle of Deep Carbon Science, in which I will present the first history of deep carbon science. I will identify and document key discoveries, the impact of new knowledge, and the roles of deep carbon scientists and their institutions from the 1400s to the present. This innovative book will set down the engaging human story of many remarkable scientists from whom we have learned about Earth's interior, and particularly the fascinating story of carbon in Earth. I will describe a great journey of discovery that has led to a better understanding of the physical, chemical, and biological behaviour of carbon in the vast majority of Earth's interior. My poster has a list of remarkable Deep Carbon Explorers, from Georgius Agricola (1494-1555) to Claude ZoBell (1904-1989). Come along to my poster and add to my compilation: choose pioneers from history, or nominate your colleagues, or even add a selfie! As a biographer, I am keen to add researchers who may have been overlooked in the standard histories of geology and geophysics. And I am always on the lookout for standout stories and personal recollections. I am equipped to do oral history interviews. What's your story? Cambridge University Press will publish the book in 2019.

  13. Drilling into the deep interior of the Nankai accretionary prism: Preliminary results of IODP NanTroSEIZE Expedition 348

    NASA Astrophysics Data System (ADS)

    Tobin, H. J.; Hirose, T.; Saffer, D. M.; Toczko, S.; Maeda, L.

    2014-12-01

    International Ocean Discovery Program (IODP) Expedition 348, the latest advance of the NanTroSEIZE project, started on 13 September 2013 and was completed on 29 January 2014. During Expedition 348, the drilling vessel Chikyu advanced the ultra-deep riser hole at Site C0002, located 80 km offshore of the Kii Peninsula, from a depth of 860 meters below sea floor (mbsf) to 3058.5 mbsf, the world record for the deepest scientific ocean drilling, and cased it for future deepening. The drilling operation successfully obtained data on formation physical properties from logging while drilling (LWD) tools, as well as from lithological analyses of cuttings and core from the interior of the active accretionary prism at the Nankai Trough. IODP Site C0002 is the currently only borehole to access the deep interior of an active convergent margin. Preliminary scientific results of Expedition 348 are as follows: (1) Fine-grained turbiditic mudstones with coarser silty and sandy interbeds, exhibiting steep dips (between ~60 and 90 degrees) are predominant in the prism down to ~3000 mbsf. The biostratigraphic age of the sediments in the lowermost part of the hole is thought to be 9-11 Ma, with an assumed age of accretion of 3-5 Ma. (2) Slickenlined surfaces, deformation bands and mineral veins are present throughout the drilled interval, while well-developed scaly clay fabrics are increasingly observed below ~2200 mbsf. A substantial fault zone with well-developed foliation was successfully cored from the deep interior of the prism at ~2205 mbsf. (3) Porosity generally decreases from ~60% to ~20% from the seafloor to 3000 mbsf. However, physical properties including grain density, electrical conductivity and P-wave velocity suggest fairly homogeneous properties in the interior of the prism between ~2000 and 3000 mbsf. (4) Mud gas analysis during the riser drilling indicates that a source of methane gas shifts from microbial origin to thermogenic at around 2325 mbsf. (5) The maximum horizontal principal stress at ~2200 mbsf is in the NE-SW direction. The inner wedge at ~ 2000 mbsf is currently in a strike-slip stress regime.

  14. Thermal response to firefighting activities in residential structure fires: impact of job assignment and suppression tactic.

    PubMed

    Horn, Gavin P; Kesler, Richard M; Kerber, Steve; Fent, Kenneth W; Schroeder, Tad J; Scott, William S; Fehling, Patricia C; Fernhall, Bo; Smith, Denise L

    2018-03-01

    Firefighters' thermal burden is generally attributed to high heat loads from the fire and metabolic heat generation, which may vary between job assignments and suppression tactic employed. Utilising a full-sized residential structure, firefighters were deployed in six job assignments utilising two attack tactics (1. Water applied from the interior, or 2. Exterior water application before transitioning to the interior). Environmental temperatures decreased after water application, but more rapidly with transitional attack. Local ambient temperatures for inside operation firefighters were higher than other positions (average ~10-30 °C). Rapid elevations in skin temperature were found for all job assignments other than outside command. Neck skin temperatures for inside attack firefighters were ~0.5 °C lower when the transitional tactic was employed. Significantly higher core temperatures were measured for the outside ventilation and overhaul positions than the inside positions (~0.6-0.9 °C). Firefighters working at all fireground positions must be monitored and relieved based on intensity and duration. Practitioner Summary: Testing was done to characterise the thermal burden experienced by firefighters in different job assignments who responded to controlled residential fires (with typical furnishings) using two tactics. Ambient, skin and core temperatures varied based on job assignment and tactic employed, with rapid elevations in core temperature in many roles.

  15. The Damping Rates of Embedded Oscillating Starless Cores

    NASA Astrophysics Data System (ADS)

    Broderick, Avery E.; Narayan, Ramesh; Keto, Eric; Lada, Charles J.

    2008-08-01

    In a previous paper we demonstrated that nonradial hydrodynamic oscillations of a thermally supported (Bonnor-Ebert) sphere embedded in a low-density, high-temperature medium persist for many periods. The predicted column density variations and molecular spectral line profiles are similar to those observed in the Bok globule B68, suggesting that the motions in some starless cores may be oscillating perturbations on a thermally supported equilibrium structure. Such oscillations can produce molecular line maps which mimic rotation, collapse, or expansion and, thus, could make determining the dynamical state from such observations alone difficult. However, while B68 is embedded in a very hot, low-density medium, many starless cores are not, having interior/exterior density contrasts closer to unity. In this paper we investigate the oscillation damping rate as a function of the exterior density. For concreteness we use the same interior model employed by Broderick et al., with varying models for the exterior gas. We also develop a simple analytical formalism, based on the linear perturbation analysis of the oscillations, which predicts the contribution to the damping rates due to the excitation of sound waves in the external medium. We find that the damping rate of oscillations on globules in dense molecular environments is always many periods, corresponding to hundreds of thousands of years and persisting over the inferred lifetimes of the globules.

  16. First-Principles Computer Simulations of Dense Plasmas and Application to the Interiors of Giant Planets

    NASA Astrophysics Data System (ADS)

    Militzer, Burkhard

    2013-06-01

    This presentation will review three recent applications of first-principles computer simulation techniques to study matter at extreme temperature-pressure conditions that are of relevance to astrophysics. First we report a recent methodological advance in all-electron path integral Monte Carlo (PIMC) that allowed us to extend this method beyond hydrogen and helium to elements with core electrons [1]. We combine results from PIMC and with density functional molecular dynamics (DFT-MD) simulations and derive a coherent equation of state (EOS) for water and carbon plasmas in the regime from 1-50 Mbar and 104-109 K that can be compared to laboratory shock wave experiments. Second we apply DFT-MD simulations to characterize superionic water in the interiors of Uranus and Neptune. By adopting a thermodynamic integration technique, we derive the Gibbs free energy in order to demonstrate the existence of a phase transformation from body-centered cubic to face-centered cubic superionic water [2]. Finally we again use DFT-MD to study the interiors of gas giant planets. We determine the EOS for hydrogen-helium mixtures spanning density-temperature conditions in the deep interiors of giant planets, 0.2-9.0 g/cc and 1000-80000 K [3]. We compare the simulation results with the semi-analytical EOS model by Saumon and Chabrier. We present a revision to the mass-radius relationship which makes the hottest exoplanets increase in radius by ~0.2 Jupiter radii at fixed entropy and for masses greater than 0.5 Jupiter masses. This change is large enough to have possible implications for some discrepant inflated giant exoplanets. We conclude by demonstrating that all materials in the cores of giant planets, ices, MgO, SiO2, and iron, will all dissolve into metallic hydrogen. This implies the cores of Jupiter and Saturn have been at least partially eroded. [1] K. P. Driver, B. Militzer, Phys. Rev. Lett. 108 (2012) 115502. [2] H. F. Wilson, M. L. Wong, B. Militzer, http://arxiv.org/abs/1211.6482. [3] B. Militzer, Phys. Rev. B 87 (2013) 014202; http://arxiv.org/abs/1302.4691. [4] H. F. Wilson, B. Militzer, Astrophys. J. Lett. 745 (2011) 54; Phys. Rev. Lett. 108 (2012) 111101.

  17. Climate Changes Documented in Ice Core Records from Third Pole Glaciers, with Emphasis on the Guliya Ice Cap in the Western Kunlun Mountains over the Last 100 Years

    NASA Astrophysics Data System (ADS)

    Thompson, L. G.; Yao, T.; Beaudon, E.; Mosley-Thompson, E.; Davis, M. E.; Kenny, D. V.; Lin, P. N.

    2016-12-01

    The Third Pole (TP) is a rapidly warming region containing 100,000 km2 of ice cover that collectively holds one of Earth's largest stores of freshwater that feeds Asia's largest rivers and helps sustain 1.5 billion people. Information on the accelerating warming in the region, its impact on the glaciers and subsequently on future water resources is urgently needed to guide mitigation and adaptation policies. Ice core histories collected over the last three decades across the TP demonstrate its climatic complexity and diversity. Here we present preliminary results from the flagship project of the Third Pole Environment Program, the 2015 Sino-American cooperative ice core drilling of the Guliya ice cap in the Kunlun Mountains in the western TP near the northern limit of the region influenced by the southwest monsoon. Three ice cores, each 51 meters in length, were recovered from the summit ( 6700 masl) while two deeper cores, one to bedrock ( 310 meters), were recovered from the plateau ( 6200 masl). Across the ice cap the net balance (accumulation) has increased annually by 2.3 cm of water equivalent from 1963-1992 to 1992-2015, and average oxygen isotopic ratios (δ18O) have enriched by 2‰. This contrasts with the recent ablation on the Naimona'nyi glacier located 540 km south of Guliya in the western Himalaya. Borehole temperatures in 2015 on the Guliya plateau have warmed substantially in the upper 30 meters of the ice compared to temperatures in 1992, when the first deep-drilling of the Guliya plateau was conducted. Compared with glaciers in the northern and western TP, the Himalayan ice fields are more sensitive to both fluctuations in the South Asian Monsoon and rising temperatures in the region. We examine the climatic changes of the last century preserved in ice core records from sites throughout the TP and compare them with those reconstructed for earlier warm epochs, such as the Medieval Climate Anomaly ( 950-1250 AD), the early Holocene "Hypsithermal" ( 5 to 9 kyr BP) and the Eemian (present only in Guliya). The latter epoch is the latest period when Earth may have been as warm as today and thus serves as an analog for the developing greenhouse world.

  18. Lunar Laser Ranging Science: Gravitational Physics and Lunar Interior and Geodesy

    NASA Technical Reports Server (NTRS)

    Williams, James G.; Turyshev, Slava G.; Boggs, Dale H.; Ratcliff, J. Todd

    2004-01-01

    Laser pulses fired at retroreflectors on the Moon provide very accurate ranges. Analysis yields information on Earth, Moon, and orbit. The highly accurate retroreflector positions have uncertainties less than a meter. Tides on the Moon show strong dissipation, with Q=33+/-4 at a month and a weak dependence on period. Lunar rotation depends on interior properties; a fluid core is indicated with radius approx.20% that of the Moon. Tests of relativistic gravity verify the equivalence principle to +/-1.4x10(exp -13), limit deviations from Einstein's general relativity, and show no rate for the gravitational constant G/G with uncertainty 9x10(exp -13)/yr.

  19. Structure of the lunar interior from magnetic field measurements

    NASA Technical Reports Server (NTRS)

    Dyal, P.; Parkin, C. W.; Daily, W. D.

    1976-01-01

    A network of lunar surface and orbiting magnetometers was used to obtain measurements of electrical conductivity and magnetic permeability of the lunar interior. An exceptionally large solar transient event, when the moon was in a geomagnetic tail lobe, enabled the most accurate lunar electromagnetic sounding information to date to be obtained. A new analytical technique using a network of two surface magnetometers and a satellite magnetometer superimposes many time series measurements to improve the signal-to-noise ratio and uses both the amplitude and phase information of all three vector components of the magnetic field data. Size constraints on a hypothetical highly conducting lunar core are investigated with the aid of the permeability results.

  20. The synthesis of four-layer gold-silver-polymer-silver core-shell nanomushroom with inbuilt Raman molecule for surface-enhanced Raman scattering

    NASA Astrophysics Data System (ADS)

    Jiang, Tao; Wang, Xiaolong; Zhou, Jun

    2017-12-01

    A facial two-step reduction method was proposed to synthesize four-layer gold-silver-polymer-silver (Au@Ag@PSPAA@Ag) core-shell nanomushrooms (NMs) with inbuilt Raman molecule. The surface-enhanced Raman scattering (SERS) intensity of 4MBA adhered on the surface of Au core gradually increased with the modification of middle Ag shell and then Ag mushroom cap due to the formation of two kinds of ultra-small interior nanogap. Compared with the initial Au nanoparticles, the SERS enhancement ratio of the Au@Ag@PSPAA@Ag NMs approached to nearly 40. The novel core-shell NMs also exhibited homogeneous SERS signals for only one sample and reproducible signals for 10 different samples, certified by the low relative standard deviation values of less than 10% and 15% for the character peaks of 4-mercaptobenzoic acid, respectively. Such a novel four-layer core-shell nanostructure with reliable SERS performance has great potential application in quantitative SERS-based immunoassay.

  1. A PIV Study of Slotted Air Injection for Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Henderson, Brenda S.; Wernet, Mark P.

    2012-01-01

    Results from acoustic and Particle Image Velocimetry (PIV) measurements are presented for single and dual-stream jets with fluidic injection on the core stream. The fluidic injection nozzles delivered air to the jet through slots on the interior of the nozzle at the nozzle trailing edge. The investigations include subsonic and supersonic jet conditions. Reductions in broadband shock noise and low frequency mixing noise were obtained with the introduction of fluidic injection on single stream jets. Fluidic injection was found to eliminate shock cells, increase jet mixing, and reduce turbulent kinetic energy levels near the end of the potential core. For dual-stream subsonic jets, the introduction of fluidic injection reduced low frequency noise in the peak jet noise direction and enhanced jet mixing. For dual-stream jets with supersonic fan streams and subsonic core streams, the introduction of fluidic injection in the core stream impacted the jet shock cell structure but had little effect on mixing between the core and fan streams.

  2. Post-fire burn severity and vegetation response following eight large wildfires across the Western United States

    Treesearch

    Leigh B. Lentile; Penelope Morgan; Andrew T. Hudak; Michael J. Bobbitt; Sarah A. Lewis; Alistair M. S. Smith; Peter R. Robichaud

    2007-01-01

    Vegetation response and burn severity were examined following eight large wildfires that burned in 2003 and 2004: two wildfires in California chaparral, two each in dry and moist mixed-conifer forests in Montana, and two in boreal forests in interior Alaska. Our research objectives were: 1) to characterize one year post-fire vegetation recovery relative to initial fire...

  3. Local-scale controls of a low-severity fire regime (1750-1950), southern British Columbia, Canada

    Treesearch

    Emily K. Heyerdahl; Ken Lertzman; Stephen Karpuk

    2007-01-01

    Historical low-severity fire regimes are well characterized in ponderosa pine and mixed-conifer forests at many sites in the western United States, but not in the southern interior of British Columbia, Canada. We reconstructed a history of low-severity fires (1750-1950) near the northern limit of ponderosa pine and demonstrated that local-scale spatial variation in...

  4. Validating the Malheur model for predicting ponderosa pine post-fire mortality using 24 fires in the Pacific Northwest, USA

    Treesearch

    Walter G. Thies; Douglas J. Westlind

    2012-01-01

    Fires, whether intentionally or accidentally set, commonly occur in western interior forests of the US. Following fire, managers need the ability to predict mortality of individual trees based on easily observed characteristics. Previously, a two-factor model using crown scorch and bole scorch proportions was developed with data from 3415 trees for predicting the...

  5. Assessing mechanical mastication and thinning-piling-burning treatments on the pinyon-juniper woodlands of southwestern Colorado

    Treesearch

    Gerald Gottfried; Steve Overby

    2011-01-01

    New knowledge of fire regimes in the pinyon-juniper woodlands of the interior western United States has altered management views. Once known as being at low wildfire risk, these woodlands are now at a higher risk for severe wildfires because of high tree densities exacerbated by ongoing drought and region-wide bark beetle (Ips confusus) infestation. To help reduce...

  6. Geohydrologic systems in Kansas physical framework of the upper aquifer unit in the western interior plains aquifer system

    USGS Publications Warehouse

    Hansen, Cristi V.; Spinazola, Joseph M.; Underwood, E.J.; Wolf, R.J.

    1992-01-01

    The purpose of this Hydrologic Investigations Atlas is to provide a description of the principal geohydrologic systems in Upper Cambrian through Lower Cretaceous rocks in Kansas. This investigation was made as part of the Central Midwest Regional Aquifer-System Analysis (CMRASA). The CMRASA is one of several major investigations by the U.S. Geological Survey of regional aquifer systems in the United States. These regional investigations are designed to increase knowledge of the flow regime and hydrologic properties of major aquifer systems and to provide quantitative information for the assessment, development, and management water supplies. The CMRASA study area includes all or parts of 10 Central Midwestern States (Jorgensen and Signor, 1981), as shown on the envelope cover.This Hydrologic Investigations Atlas, which consists of a series of nine chapters, presents a description of the physical framework and the geohydrology of principal aquifers and confining systems in Kansas. Chapter D presents maps that show the areal extent, altitude and configuration of the top, and thickness of Mississippian rocks that compose the upper aquifer unit of the Western Interior Plains aquifer system in Kansas, The chapter is limited to the presentation of the physical framework of the upper aquifer unit. The interpretation of the physical framework of the upper aquifer unit is based on selected geophysical and lithologic logs and published maps of stratigraphically equivalent units. Maps indicating the thickness and the altitude and configuration of the top of the upper aquifer unit in the Western Interior Plains aquifer system have been prepared as part of a series of interrelated maps that describe the stratigraphic interval from the Precambrian basement through Lower Cretaceous rocks. A concerted effort was made to ensure that maps of each geohydrologic unit are consistent with the maps of underlying and overlying units. Chapter A of this atlas series (Wolf and others, 1990) describes the relation of principal geohydrologic systems in Kansas and presents a more detailed discussion of the methods and data used to prepare and ensure consistency among the sets of maps.

  7. Chronostratigraphy and paleoenvironmental change in the Makarov Basin of the western Arctic Ocean during the last 1 Ma

    NASA Astrophysics Data System (ADS)

    Park, K.; Nam, S. I.; Khim, B. K.; Kong, G. S.; Schreck, M.; Mackensen, A.; Niessen, F.

    2017-12-01

    Establishing an accurate chronostratigraphy is essential in reconstructing paleoenvironmental changes in the Arctic Ocean. This requisition, however, has been impeded by the lack of biogenic remnants such as calcareous and siliceous microfossils, as well as alteration of paleomagnetic properties by post-depositional processes. Consequently, foundation of chronostratigraphy in the Arctic Ocean has been mostly relying on stratigraphic correlations. This study examines lithological features and physical properties of sediments of gravity core ARA03B-41GC02 collected in the Makarov Basin and correlates with previously studied cores from the western Arctic Ocean, in order to establish an age model that could eventually facilitate a precise reconstruction of paleoenvironmental changes in the western Arctic Ocean. Age control in the uppermost part was determined by AMS 14C dating of planktonic foraminifera and inter-core correlation was conducted in the upper ca. 3.8 m of the core which corresponded to MIS 15. Age constraints older than MIS 15 were treated using cyclostratigraphic model based on Mn-δ18O stack comparison, assuming that brown and high Mn concentration layers represent generally interglacial or interstadial periods. Based on our result, the core bottom corresponds to MIS 28 with an average sedimentation rate of ca. 0.5 cm/ky. The first appearance of detrital carbonate, planktonic foraminifera, and benthic foraminifera occurred during MIS 16, 11, and 7, respectively. MIS 16 is known as the coldest glacial period when δ18O of the LR04 stack first becomes heavier than 5‰; the occurrence of detrital carbonate likely transported from the Canadian Arctic indicates the initial buildup of the large ice sheets in the North America during this time. Since MIS 11 which is known as the warmest interglacial period during the late Pleistocene in the Northern Hemisphere, the appearance of planktonic foraminifera represents the warmer condition during interglacial periods in the western central Arctic Ocean. Additional geochemical and mineralogical proxies need to be conducted for better understanding of depositional environments and sediment provenance as well as transport pathways.

  8. Sedimentary record of environmental pollution in the Western Baltic Sea

    NASA Astrophysics Data System (ADS)

    Müller, German; Dominik, J.; Reuther, R.; Malisch, R.; Schulte, E.; Acker, L.; Irion, G.

    1980-12-01

    The chronological development of environmental pollution in the Western Baltic Sea for the past hundred years was investigated in dated sediment cores. An artificial radionuclide (137Cs), nutrients, heavy metals, chlorinated hydrocarbons (PCB, DDT, Lindane) and plasticizers (phthalate esters) show characteristic distribution patterns within the various cores. They can be related to the production and use of specific chemicals and goods, to emissions associated with the increased combustion of coal parallel to industrialization and —in the case of 137Cs — to emissions associated with atomic weapons tests in the high atmosphere. Characteristic trends in the general development of pollution may be superimposed by specific emissions from local sources.

  9. Abrupt climate shift in the Western Mediterranean Sea.

    PubMed

    Schroeder, K; Chiggiato, J; Bryden, H L; Borghini, M; Ben Ismail, S

    2016-03-11

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected.

  10. Abrupt climate shift in the Western Mediterranean Sea

    PubMed Central

    Schroeder, K.; Chiggiato, J.; Bryden, H. L.; Borghini, M.; Ben Ismail, S.

    2016-01-01

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected. PMID:26965790

  11. Phase equilibria of a low S and C lunar core: Implications for an early lunar dynamo and physical state of the current core

    NASA Astrophysics Data System (ADS)

    Righter, K.; Go, B. M.; Pando, K. A.; Danielson, L.; Ross, D. K.; Rahman, Z.; Keller, L. P.

    2017-04-01

    Multiple lines of geochemical and geophysical evidence suggest the Moon has a small metallic core, yet the composition of the core is poorly constrained. The physical state of the core (now or in the past) depends on detailed knowledge of its composition, and unfortunately, there is little available data on relevant multicomponent systems (i.e., Fe-Ni-S-C) at lunar interior conditions. In particular, there is a dearth of phase equilibrium data to elucidate whether a specific core composition could help to explain an early lunar geodynamo and magnetic field intensities, or current solid inner core/liquid outer core states. We utilize geochemical information to estimate the Ni, S and C contents of the lunar core, and then carry out phase equilibria experiments on several possible core compositions at the pressure and temperature conditions relevant to the lunar interior. The first composition is 0.5 wt% S and 0.375 wt% C, based on S and C contents of Apollo glasses. A second composition contains 1 wt% each of S and C, and assumes that the lunar mantle experienced degassing of up to 50% of its S and C. Finally a third composition contains C as the dominant light element. Phase equilibrium experiments were completed at 1, 3 and 5 GPa, using piston cylinder and multi-anvil techniques. The first composition has a liquidus near 1550 °C and solidus near 1250 °C. The second composition has a narrower liquidus and solidus temperatures of 1400 and 1270 °C, respectively, while the third composition is molten down to 1150 °C. As the composition crystallizes, the residual liquid becomes enriched in S and C, but S enrichment is greater due to the incorporation of C (but not S) into solid metallic FeNi. Comparison of these results to thermal models for the Moon allow an evaluation of which composition is consistent with the geophysical data of an early dynamo and a currently solid inner and liquid outer core. Composition 1 has a high enough liquidus to start crystallizing early in lunar history (4.3 Ga), consistent with the possible core dynamo initiated by crystallization of a solid inner core. Composition 1 also stays partially molten throughout lunar history, and could easily explain the seismic data. Composition 2, on the other hand, can satisfy one or the other set of geophysical data, but not both and thus seems like a poor candidate for a lunar core composition. Composition 3 remains molten to temperatures that are lower than current estimates for the lunar core, thus ruling out the possibility of a C-rich (and S-poor) lunar core. The S- and C-poor core composition studied here (composition 1) is consistent with all available geochemical and geophysical data and provides a simple heat source and mechanism for a lunar core dynamo (core crystallization) that would obviate the need for other primary mechanisms such as impacts, core-mantle coupling, or unusual thermal histories.

  12. InSight Prelaunch Briefing

    NASA Image and Video Library

    2018-05-03

    The United Launch Alliance (ULA) Atlas-V rocket is seen with NASA's InSight spacecraft onboard, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  13. InSight Prelaunch

    NASA Image and Video Library

    2018-05-03

    The United Launch Alliance (ULA) Atlas-V rocket is seen with NASA's InSight spacecraft onboard, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  14. InSight Prelaunch Briefing

    NASA Image and Video Library

    2018-05-03

    NASA Chief Scientist Jim Green discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  15. Properties of the moon and its environment from lunar magnetometer measurements

    NASA Technical Reports Server (NTRS)

    Parkin, C. W.

    1976-01-01

    Lunar analysis of data from a total of nine lunar magnetometers is described. Results obtained concerning electromagnetic, compositional, and structural properties of the lunar interior are discussed. Specific topics covered include: lunar magnetic permeability and iron abundance; limits on a highly conducting lunar core; lunar electrical conductivity; and internal structure inferred from conductivity and permeability results.

  16. Wetland succession in a permafrost collapse: interations between fire and thermokarst

    Treesearch

    I.H. Myers-Smith; J.W. Harden; M. Wilmking; C.C. Fuller; A.D. McGuire; F.S. III Chapin

    2008-01-01

    To determine the influence of fire and thermokarst in a boreal landscape, we investigated peat cores within and adjacent to a permafrost collapse feature on the Tanana River Floodplain of Interior Alaska. Radioisotope dating, diatom assemblages, plant macrofossils, charcoal fragments, and carbon and nitrogen content of the peat profile indicate ~600 years of vegetation...

  17. Both core and F proteins of hepatitis C virus could enhance cell proliferation in transgenic mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, Wen-Ta; Li, Hui-Chun; Lee, Shen-Kao

    Highlights: •HCV core and F proteins could induce hepatocyte proliferation in the transgenic mice. •β-Catenin signaling pathway was activated by core protein in the transgenic mice. •β-Catenin signaling pathway was activated by myc-F protein in the transgenic mice. •Expression of SMA protein was enhanced by core but not myc-F protein. -- Abstract: The role of the protein encoded by the alternative open reading frame (ARF/F/core+1) of the Hepatitis C virus (HCV) genome in viral pathogenesis remains unknown. The different forms of ARF/F/core+1 protein were labile in cultured cells, a myc-tag fused at the N-terminus of the F protein made itmore » more stable. To determine the role of core and F proteins in HCV pathogenesis, transgenic mice with either protein expression under the control of Albumin promoter were generated. Expression of core protein and F protein with myc tag (myc-F) could be detected by Western blotting analysis in the livers of these mice. The ratio of liver to body weight is increased for both core and myc-F transgenic mice compared to that of wild type mice. Indeed, the proliferating cell nuclear antigen protein, a proliferation marker, was up-regulated in the transgenic mice with core or myc-F protein. Further analyses by microarray and Western blotting suggested that β-catenin signaling pathway was activated by either core or myc-F protein in the transgenic mice. These transgenic mice were further treated with either Diethynitrosamine (a tumor initiator) or Phenobarbital (a tumor promoter). Phenobarbital but not Diethynitrosamine treatment could increase the liver/body weight ratio of these mice. However, no tumor formation was observed in these mice. In conclusion, HCV core and myc-F proteins could induce hepatocyte proliferation in the transgenic mice possibly through β-catenin signaling pathway.« less

  18. Source identification of western Oregon Douglas-fir wood cores using mass spectrometry and random forest classification1

    PubMed Central

    Finch, Kristen; Espinoza, Edgard; Jones, F. Andrew; Cronn, Richard

    2017-01-01

    Premise of the study: We investigated whether wood metabolite profiles from direct analysis in real time (time-of-flight) mass spectrometry (DART-TOFMS) could be used to determine the geographic origin of Douglas-fir wood cores originating from two regions in western Oregon, USA. Methods: Three annual ring mass spectra were obtained from 188 adult Douglas-fir trees, and these were analyzed using random forest models to determine whether samples could be classified to geographic origin, growth year, or growth year and geographic origin. Specific wood molecules that contributed to geographic discrimination were identified. Results: Douglas-fir mass spectra could be differentiated into two geographic classes with an accuracy between 70% and 76%. Classification models could not accurately classify sample mass spectra based on growth year. Thirty-two molecules were identified as key for classifying western Oregon Douglas-fir wood cores to geographic origin. Discussion: DART-TOFMS is capable of detecting minute but regionally informative differences in wood molecules over a small geographic scale, and these differences made it possible to predict the geographic origin of Douglas-fir wood with moderate accuracy. Studies involving DART-TOFMS, alone and in combination with other technologies, will be relevant for identifying the geographic origin of illegally harvested wood. PMID:28529831

  19. Frozen Nature - A high-alpine ice core record reveals fire and vegetation dynamics in Western Europe over the past millennium

    NASA Astrophysics Data System (ADS)

    Brügger, S.; Gobet, E.; Sigl, M.; Osmont, D.; Schwikowski, M.; Tinner, W.

    2017-12-01

    Wild fires are an ecological disturbance agent across ecosystems, driving vegetation dynamics and resulting in disruption of habitats (Moritz et al. 2014).We analyze pollen and spores as proxies for vegetation composition, structure and agricultural activity, microscopic charcoal as a proxy for fire activity, and spheroidal carbonaceous particles (SCPs or soots) as a proxy for fossil fuel combustion which preserve in ice cores over millennia (Eichler et al. 2011).Our high-alpine ice core (4452 m a.s.l.) from Colle Gnifetti, Swiss Alps is located in the center of Western Europe, thus allowing to assess vegetation and societal responses to climatic change and wildfire disturbance on a subcontinental scale. The record covers the last millennium with an excellent chronological control (Jenk et al. 2009, Sigl et al. 2009), particularly over the most recent 200 years - the period that experienced important climatic changes and an increasing globalization of economy.The Colle Gnifetti record reflects large scale impacts such as extreme weather, societal innovations, agricultural crises and pollution of the industrial period in Western Europe. Pollution tracers occur in the record as early as 1750 AD and coincide with the shift to large-scale maize production in Northern Italy and with increased fire activity. Our multiproxy record may allow desentagling the role of climate and humans for vegetation composition and biomass burning. The attribution of causes may significantly advance our understanding of future vegetation and fire dynamics under global change conditions. To our knowledge we present the first long-term high-resolution palynological record of a high elevation ice core in Europe.REFERENCESEichler et al. (2011): An ice-core based history of Siberian forest fires since AD 1250. Quaternary Science Reviews, 30(9), 1027-1034.Jenk et al. (2009): A novel radiocarbon dating technique applied to an ice core from the Alps indicating late Pleistocene ages. Journal of Geophysical Research: Atmospheres, 114(D14).Moritz et al. (2014): Learning to coexist with wildfire. Nature, 515(7525), 58-66.Sigl et al. (2009): Towards radiocarbon dating of ice cores. Journal of Glaciology, 55(194), 985-996.

  20. Forward and inverse modeling for jovian seismology

    NASA Astrophysics Data System (ADS)

    Jackiewicz, Jason; Nettelmann, Nadine; Marley, Mark; Fortney, Jonathan

    2012-08-01

    Jupiter is expected to pulsate in a spectrum of acoustic modes and recent re-analysis of a spectroscopic time series has identified a regular pattern in the spacing of the frequencies (Gaulme, P., Schmider, F.-X., Gay, J., Guillot, T., Jacob, C. [2011]. Astron. Astrophys. 531, A104). This exciting result can provide constraints on gross jovian properties and warrants a more in-depth theoretical study of the seismic structure of Jupiter. With current instrumentation, such as the SYMPA instrument (Schmider, F.X. [2007]. Astron. Astrophys. 474, 1073-1080) used for the Gaulme et al. (Gaulme, P., Schmider, F.-X., Gay, J., Guillot, T., Jacob, C. [2011]. Astron. Astrophys. 531, A104) analysis, we assume that, at minimum, a set of global frequencies extending up to angular degree ℓ=25 could be observed. In order to identify which modes would best constraining models of Jupiter's interior and thus help motivate the next generation of observations, we explore the sensitivity of derived parameters to this mode set. Three different models of the jovian interior are computed and the theoretical pulsation spectrum from these models for ℓ⩽25 is obtained. We compute sensitivity kernels and perform linear inversions to infer details of the expected discontinuities in the profiles in the jovian interior. We find that the amplitude of the sound-speed jump of a few percent in the inner/outer envelope boundary seen in two of the applied models should be reasonably inferred with these particular modes. Near the core boundary where models predict large density discontinuities, the location of such features can be accurately measured, while their amplitudes have more uncertainty. These results suggest that this mode set would be sufficient to infer the radial location and strength of expected discontinuities in Jupiter's interior, and place strong constraints on the core size and mass. We encourage new observations to detect these jovian oscillations.

  1. Fueling plankton production by a meandering frontal jet: a case study for the Alboran Sea (Western Mediterranean).

    PubMed

    Oguz, Temel; Macias, Diego; Garcia-Lafuente, Jesus; Pascual, Ananda; Tintore, Joaquin

    2014-01-01

    A three dimensional biophysical model was employed to illustrate the biological impacts of a meandering frontal jet, in terms of efficiency and persistency of the autotrophic frontal production, in marginal and semi-enclosed seas. We used the Alboran Sea of the Western Mediterranean as a case study. Here, a frontal jet with a width of 15-20 km, characterized by the relatively low density Atlantic water mass, flows eastward within the upper 100 m as a marked meandering current around the western and the eastern anticyclonic gyres prior to its attachment to the North African shelf/slope topography of the Algerian basin. Its inherent nonlinearity leads to the development of a strong ageostrophic cross-frontal circulation that supplies nutrients into the nutrient-starved euphotic layer and stimulates phytoplankton growth along the jet. Biological production is larger in the western part of the basin and decreases eastwards with the gradual weakening of the jet. The higher production at the subsurface levels suggests that the Alboran Sea is likely more productive than predicted by the satellite chlorophyll data. The Mediterranean water mass away from the jet and the interiors of the western and eastern anticyclonic gyres remain unproductive.

  2. Modeling Approaches in Planetary Seismology

    NASA Technical Reports Server (NTRS)

    Weber, Renee; Knapmeyer, Martin; Panning, Mark; Schmerr, Nick

    2014-01-01

    Of the many geophysical means that can be used to probe a planet's interior, seismology remains the most direct. Given that the seismic data gathered on the Moon over 40 years ago revolutionized our understanding of the Moon and are still being used today to produce new insight into the state of the lunar interior, it is no wonder that many future missions, both real and conceptual, plan to take seismometers to other planets. To best facilitate the return of high-quality data from these instruments, as well as to further our understanding of the dynamic processes that modify a planet's interior, various modeling approaches are used to quantify parameters such as the amount and distribution of seismicity, tidal deformation, and seismic structure on and of the terrestrial planets. In addition, recent advances in wavefield modeling have permitted a renewed look at seismic energy transmission and the effects of attenuation and scattering, as well as the presence and effect of a core, on recorded seismograms. In this chapter, we will review these approaches.

  3. Magnetism and the interior of the moon. [measured at Apollo landing sites

    NASA Technical Reports Server (NTRS)

    Dyal, P.; Parkin, C. W.; Daily, W. D.

    1974-01-01

    During the time period 1961-1972 eleven magnetometers were sent to the moon. The results of lunar magnetometer data analysis are reviewed, with emphasis on the lunar interior. Magnetic fields have been measured on the lunar surface at the Apollo 12, 14, 15, and 16 landing sites. The remanent field values at these sites are given. Satellite and surface measurements show strong evidence that the lunar crust is magnetized over much of the lunar globe. The origin of the lunar remanent field is not yet satisfactorily understood; several source models are presented. Simultaneous data from the Apollo 12 lunar surface magnetometer and the Explorer 35 Ames magnetometer are used to construct a wholemoon hysteresis curve, from which the global lunar permeability is determined. Total iron abundance is calculated for two assumed compositional models of the lunar interior. Other lunar models with a small iron core and with a shallow iron-rich layer are also discussed in light of the measured global permeability.

  4. New initiative in studies of Earth's deep interior

    NASA Astrophysics Data System (ADS)

    Lay, Thorne

    A multidisciplinary U.S. research community is undertaking a new coordinated effort to study the state and dynamics of the Earth's deep mantle and core. At an open meeting held at the Massachusetts Institute of Technology, Cambridge, from September 11 to 12, 1992, over 120 Earth scientists gathered to discuss this new program, which is an outgrowth of activity during the previous year by an ad hoc steering committee. The research program will be coordinated by a community-based scientific organization and supported through competitive research proposals submitted to the National Science Foundation with the aim of facilitating cooperative research projects cutting across traditional disciplinary and institutional boundaries.The new organization is the U.S. Studies of the Earth's Deep Interior (SEDI) Coordinating Committee. This committee will facilitate communication among the U.S. SEDI research community, federal funding agencies, the AGU Committee for Studies of the Earth's Interior (SEI), the Union SEDI Committee of the International Union of Geodesy and Geophysics, and the general public (Figure 1).

  5. Seismic structures in the inner and outer core constrained by the PKP observations near the caustic distance range

    NASA Astrophysics Data System (ADS)

    Yu, W.; Wen, L.; Niu, F.

    2002-05-01

    We have extensively collected PKP waveforms around the PKP caustic distance range (141o - 147o) recorded in several dense regional arrays and the Global Seismic Network covering from 1990 to 2000. PKP observations at this distance range (141o - 147o) are usually purposely avoided in travel time analyses, because of the interference of various PKP branches. The observations there, however, will be extremely useful for constraining the seismic structures at both the top of the inner core and the bottom of the outer core. Moreover, because PKIKP phases sample a depth range of 100 km - 170 km below the inner-core boundary at this distant range, their observations fill the sampling depth gap between the PKiKP-PKIKP observations at the smaller distances and the PKPbc-PKIKP phases at the larger distances. Before the PKP caustics (141o - 145o), the diffracted PKP phases near the B caustics (PKPBdiff) and PKiKP phases are discernible in the long-period seismograms, and their differential travel times and waveforms could be used to constrain seismic structures at the bottom of the outer core and/or at the base of the mantle. The observed long-period PKiKP-PKPBdiff waveforms exhibit a hemispheric difference between those sampling the "eastern" and "western" hemispheres, with those sampling the "western" hemisphere showing larger time separations between the two phases. These observations can be explained by models with P velocity gradients of 0.0806 (km/s)/ 200 km for the "western" hemisphere and 0.114 (km/s)/200 km for the "eastern" hemisphere at the bottom of the outer core. Alternatively, these observations can also be explained by models with different velocity structures at the bottom 200 km of the mantle with P velocity variations in an order of 3 percent with respect to PREM. Broadband PKP observations after the PKP caustics (145o - 147o), on the other hand, provide high-quality constraints on the seismic structures at both the top of the inner core and the bottom of the outer core, as PKPbc phases can be used as excellent reference phases. We explore seismic models in both the bottom of the outer core and the top of the inner core, which can consistently explain the seismic observations at the caustic distance range (141o - 147o) and the PKiKP-PKIKP observations at the closer distances (Niu and Wen, Nature, 410, 1081-1084, 2001, Wen and Niu, JGR, submitted).

  6. A Model for the Thermal and Chemical Evolution of the Moon's Interior: Implications for the Onset of Mare Volcanism

    NASA Technical Reports Server (NTRS)

    Hess, Paul C.; Parmentier, E. M.

    1995-01-01

    Crystallization of the lunar magma ocean creates a chemically stratified Moon consisting of an anorthositic crust and magma ocean cumulates overlying the primitive lunar interior. Within the magma ocean cumulates the last liquids to crystallize form dense, ilmenite-rich cumulates that contain high concentrations of incompatible radioactive elements. The underlying olivine-orthopyroxene cumulates are also stratified with later crystallized, denser, more Fe-rich compositions at the top. This paper explores the chemical and thermal consequences of an internal evolution model accounting for the possible role of these sources of chemical buoyancy. Rayleigh-Taylor instability causes the dense ilmenite-rich cumulate layer and underlying Fe-rich cumulates to sink toward the center of the Moon, forming a dense lunar core. After this overturn, radioactive heating within the ilmenite-rich cumulate core heats the overlying mantle, causing it to melt. In this model, the source region for high-TiO2 mare basalts is a convectively mixed layer above the core-mantle boundary which would contain small and variable amounts of admixed ilmenite and KREEP. This deep high-pressure melting, as required for mare basalts, occurs after a reasonable time interval to explain the onset of mare basalt volcanism if the content of radioactive elements in the core and the chemical density gradients above the core are sufficiently high but within a range of values that might have been present in the Moon. Regardless of details implied by particular model parameters, gravitational overturn driven by the high density of magma ocean Fe-rich cumulates should concentrate high-TiO2 mare basalt sources, and probably a significant fraction of radioactive heating, toward the center of the Moon. This will have important implications for both the thermal evolution of the Moon and for mare basalt genesis.

  7. Equation of state of pyrite to 80 GPa and 2400 K

    DOE PAGES

    Thompson, Elizabeth C.; Chidester, Bethany A.; Fischer, Rebecca A.; ...

    2016-05-02

    The high-cosmic abundance of sulfur is not reflected in the terrestrial crust, implying it is either sequestered in the Earth’s interior or was volatilized during accretion. As it has widely been suggested that sulfur could be one of the contributing light elements leading to the density deficit of Earth’s core, a robust thermal equation of state of iron sulfide is useful for understanding the evolution and properties of Earth’s interior. We performed X-ray diffraction measurements on FeS 2 achieving pressures from 15 to 80 GPa and temperatures up to 2400 K using laser-heated diamond-anvil cells. No phase transitions were observedmore » in the pyrite structure over the pressure and temperature ranges investigated. Combining our new P-V-T data with previously published room-temperature compression and thermochemical data, we fit a Debye temperature of 624(14) K and determined a Mie-Grüneisen equation of state for pyrite having bulk modulus K T = 141.2(18) GPa, pressure derivative K' T = 5.56(24), Grüneisen parameter γ 0 = 1.41, anharmonic coefficient A 2 = 2.53(27) × 10 –3 J/(K 2·mol), and q = 2.06(27). These findings are compared to previously published equation of state parameters for pyrite from static compression, shock compression, and ab initio studies. This revised equation of state for pyrite is consistent with an outer core density deficit satisfied by 11.4(10) wt% sulfur, yet matching the bulk sound speed of PREM requires an outer core composition of 4.8(19) wt% S. Here, this discrepancy suggests that sulfur alone cannot satisfy both seismological constraints simultaneously and cannot be the only light element within Earth’s core, and so the sulfur content needed to satisfy density constraints using our FeS 2 equation of state should be considered an upper bound for sulfur in the Earth’s core.« less

  8. The Ross Sea Dipole - temperature, snow accumulation and sea ice variability in the Ross Sea region, Antarctica, over the past 2700 years

    NASA Astrophysics Data System (ADS)

    Bertler, Nancy A. N.; Conway, Howard; Dahl-Jensen, Dorthe; Emanuelsson, Daniel B.; Winstrup, Mai; Vallelonga, Paul T.; Lee, James E.; Brook, Ed J.; Severinghaus, Jeffrey P.; Fudge, Taylor J.; Keller, Elizabeth D.; Baisden, W. Troy; Hindmarsh, Richard C. A.; Neff, Peter D.; Blunier, Thomas; Edwards, Ross; Mayewski, Paul A.; Kipfstuhl, Sepp; Buizert, Christo; Canessa, Silvia; Dadic, Ruzica; Kjær, Helle A.; Kurbatov, Andrei; Zhang, Dongqi; Waddington, Edwin D.; Baccolo, Giovanni; Beers, Thomas; Brightley, Hannah J.; Carter, Lionel; Clemens-Sewall, David; Ciobanu, Viorela G.; Delmonte, Barbara; Eling, Lukas; Ellis, Aja; Ganesh, Shruthi; Golledge, Nicholas R.; Haines, Skylar; Handley, Michael; Hawley, Robert L.; Hogan, Chad M.; Johnson, Katelyn M.; Korotkikh, Elena; Lowry, Daniel P.; Mandeno, Darcy; McKay, Robert M.; Menking, James A.; Naish, Timothy R.; Noerling, Caroline; Ollive, Agathe; Orsi, Anaïs; Proemse, Bernadette C.; Pyne, Alexander R.; Pyne, Rebecca L.; Renwick, James; Scherer, Reed P.; Semper, Stefanie; Simonsen, Marius; Sneed, Sharon B.; Steig, Eric J.; Tuohy, Andrea; Ulayottil Venugopal, Abhijith; Valero-Delgado, Fernando; Venkatesh, Janani; Wang, Feitang; Wang, Shimeng; Winski, Dominic A.; Winton, V. Holly L.; Whiteford, Arran; Xiao, Cunde; Yang, Jiao; Zhang, Xin

    2018-02-01

    High-resolution, well-dated climate archives provide an opportunity to investigate the dynamic interactions of climate patterns relevant for future projections. Here, we present data from a new, annually dated ice core record from the eastern Ross Sea, named the Roosevelt Island Climate Evolution (RICE) ice core. Comparison of this record with climate reanalysis data for the 1979-2012 interval shows that RICE reliably captures temperature and snow precipitation variability in the region. Trends over the past 2700 years in RICE are shown to be distinct from those in West Antarctica and the western Ross Sea captured by other ice cores. For most of this interval, the eastern Ross Sea was warming (or showing isotopic enrichment for other reasons), with increased snow accumulation and perhaps decreased sea ice concentration. However, West Antarctica cooled and the western Ross Sea showed no significant isotope temperature trend. This pattern here is referred to as the Ross Sea Dipole. Notably, during the Little Ice Age, West Antarctica and the western Ross Sea experienced colder than average temperatures, while the eastern Ross Sea underwent a period of warming or increased isotopic enrichment. From the 17th century onwards, this dipole relationship changed. All three regions show current warming, with snow accumulation declining in West Antarctica and the eastern Ross Sea but increasing in the western Ross Sea. We interpret this pattern as reflecting an increase in sea ice in the eastern Ross Sea with perhaps the establishment of a modern Roosevelt Island polynya as a local moisture source for RICE.

  9. Osprey distribution, abundance, and status in western North America: I. The northern California population

    USGS Publications Warehouse

    Henny, Charles J.; Dunaway, David J.; Mallette, Robert D.; Koplin, James R.

    1978-01-01

    An estimated 355± 40 pairs (95 percent C.I.) of Ospreys (Pandion haliaetus carolinensis) nested in the northern California survey area in 1975. Eighty-one pairs were estimated along the extreme northern coast in Del Norte and Humboldt Counties. One hundred and forty-four pairs were estimated along California's northern coast in Mendociuo, Sonoma, and Marin Counties. The northern interior region, primarily in Siskiyou, Trinity, Shasta, Lassen, and Plumas Counties, contained an estimated 130 pairs. Forty-nine percent of the interior Osprey population is associated with reservoirs that were not present in 1900. We believe more Ospreys are present in the interior now than 75 years ago because of the increase in suitable habitat; nevertheless, populations at Shasta Lake and Clair Engle Lake are now exhibiting below-normal production rates and local declines. The long-term status of the coastal population, nesting along rivers, streams, and bays, is not clear. Recent production rates from two segments of the coastal population appear to be normal, but production at Usal Creek is below normal.

  10. Rock Magnetic Properties, Paleosecular Variation Record and Relative Paleointensity Stack between 11 and 21 14C kyr B.P. From Sediment Cores, Lake Moreno (Argentina)

    NASA Astrophysics Data System (ADS)

    Gogorza, C. S.; Irurzun, M. A.; Lirio, J. M.; Nunez, H.; Chaparro, M. A.; Sinito, A. M.

    2008-05-01

    We conducted a detailed study of natural remanence and rock magnetic properties on sediments cores from lake Moreno (South-Western Argentina). Based on these measurements, we constructed a paleosecular variation (PSV) record (Irurzun et al., 2008) and a relative paleointensity stack for the period 11-21 14C. The Declination and Inclination logs of the characteristic remanent magnetization for the cores as function of shortened depth are obtained. The data from all cores were combined to obtain a composite record using the Fisher method. Comparison between stacked inclination and declination records of lake Moreno and results obtained in previous works, lake Escondido (Gogorza et al., 1999; Gogorza et al., 2002) and lake El Trébol (Irurzun et al., 2008), shows good agreement. This agreement made possible to transform the stacked curves into time series that spans the interval 11 and 21 14C kyr B.P. Rock magnetic properties of the sediments cores showed uniform magnetic mineralogy and grain size, suggesting that they were suitable for relative paleointensity studies. The remanent magnetization at 20mT (NRM20mT) was normalized using the anhysteric remanent magnetization at 20mT (ARM20mT), the saturation of the isothermal remanent magnetization at 20mT (SIRM20mT) and the low field magnetic susceptibility {k}. Coherence analysis showed that the normalized records were not affected by local environmental conditions. The recorded pseudo-Thellier paleointensity was compared with records obtained from conventional normalizing methods. Comparing the paleointensity curves with others obtained previously in other lakes in the area has allowed us to reach reliable conclusions about centennial-scale features. References: Gogorza, C.S.G., Sinito, A.M., Di Tommaso, I., Vilas, J.F., Creer, K., Núnez, H. Holocene Geomagnetic Secular Variations Recorded by Sediments from Escondido lake (South Argentina). Earth, Planets and Space, V51(2), 93- 106. 1999. Gogorza, C.S.G., Sinito, A.M., Lirio, J.M., Núnez, H., Chaparro, M.A.E., Vilas, J.F. Paleosecular Variations 0- 19,000 Years Recorded by Sediments from Escondido lake (Argentina). Physical of the Earth and Planetary Interiors, Elsevier, V133(1-4), 35-55. 2002. Irurzun, M.A., Gogorza, C.S.G., Sinito, A.M., Chaparro, M.A.E., Nuñez, H., Lirio, J.M. Paleosecular Variations 12-20 kyr. as Recorded by Sediments From lake Moreno (Southern Argentina). Studia Geophysica et Geodaetica. In Press. 2008.

  11. Sacra Fossae

    NASA Image and Video Library

    2018-04-19

    Located on the western margin of Lunae Planum, Sacra Fossae is a group of linear depressions. The right angle turns and uniform width seen in this VIS image indicate that these channels were formed by faulting rather than liquid flow. Two bounding faults with a down-dropped interior are called graben. Orbit Number: 71244 Latitude: 17.7623 Longitude: 288.309 Instrument: VIS Captured: 2018-01-05 09:06 https://photojournal.jpl.nasa.gov/catalog/PIA22373

  12. Post-fire bedload sediment delivery across spatial scales in the interior western United States

    Treesearch

    Joseph W. Wagenbrenner; Peter R. Robichaud

    2014-01-01

    Post-fire sediment yields can be up to three orders of magnitude greater than sediment yields in unburned forests. Much of the research on post-fire erosion rates has been at small scales (100m2 or less), and post-fire sediment delivery rates across spatial scales have not been quantified in detail. We developed relationships for post-fire bedload sediment delivery...

  13. Habitat Suitability Index Models: Slough darter

    USGS Publications Warehouse

    Edwards, Elizabeth A.; Bacteller, Mary; Maughan, O. Eugene

    1982-01-01

    The native range of the slough darter (Etheostoma gracile) extends from western Alabama (Smith-Vaniz 1968) to central Texas and northward in the lowland areas of the former Mississippi Embayment and the Interior Low Plateau to central Illinois (Collette 1962) and southwestern Indiana (Gerking 1945). Its distribution also includes southeast Kansas (Metcalf 1959; Cross 1967) and northeast Oklahoma (Blair 1959). Natural hybridization with the blackside darter (Percina maculata) has been recorded (Page 1976).

  14. Effects of post-fire salvage logging and a skid trail treatment on ground cover, soils, and sediment production in the interior western United States

    Treesearch

    Joseph W. Wagenbrenner; Lee H. MacDonald; Robert N. Coats; Peter R. Robichaud; Robert E. Brown

    2015-01-01

    Post-fire salvage logging adds another set of environmental effects to recently burned areas, and previous studies have reported varying impacts on vegetation, soil disturbance, and sediment production with limited data on the underlying processes. Our objectives were to determine how: (1) ground-based post-fire logging affects surface cover, soil water repellency,...

  15. Earliest Pottery on New Guinea Mainland Reveals Austronesian Influences in Highland Environments 3000 Years Ago

    PubMed Central

    Gaffney, Dylan; Summerhayes, Glenn R.; Ford, Anne; Scott, James M.; Denham, Tim; Field, Judith; Dickinson, William R.

    2015-01-01

    Austronesian speaking peoples left Southeast Asia and entered the Western Pacific c.4000-3000 years ago, continuing on to colonise Remote Oceania for the first time, where they became the ancestral populations of Polynesians. Understanding the impact of these peoples on the mainland of New Guinea before they entered Remote Oceania has eluded archaeologists. New research from the archaeological site of Wañelek in the New Guinea Highlands has broken this silence. Petrographic and geochemical data from pottery and new radiocarbon dating demonstrates that Austronesian influences penetrated into the highland interior by 3000 years ago. One potsherd was manufactured along the northeast coast of New Guinea, whereas others were manufactured from inland materials. These findings represent the oldest securely dated pottery from an archaeological context on the island of New Guinea. Additionally, the pottery comes from the interior, suggesting the movements of people and technological practices, as well as objects at this time. The antiquity of the Wañelek pottery is coincident with the expansion of Lapita pottery in the Western Pacific. Such occupation also occurs at the same time that changes have been identified in subsistence strategies in the archaeological record at Kuk Swamp suggesting a possible link between the two. PMID:26331310

  16. Earliest Pottery on New Guinea Mainland Reveals Austronesian Influences in Highland Environments 3000 Years Ago.

    PubMed

    Gaffney, Dylan; Summerhayes, Glenn R; Ford, Anne; Scott, James M; Denham, Tim; Field, Judith; Dickinson, William R

    2015-01-01

    Austronesian speaking peoples left Southeast Asia and entered the Western Pacific c.4000-3000 years ago, continuing on to colonise Remote Oceania for the first time, where they became the ancestral populations of Polynesians. Understanding the impact of these peoples on the mainland of New Guinea before they entered Remote Oceania has eluded archaeologists. New research from the archaeological site of Wañelek in the New Guinea Highlands has broken this silence. Petrographic and geochemical data from pottery and new radiocarbon dating demonstrates that Austronesian influences penetrated into the highland interior by 3000 years ago. One potsherd was manufactured along the northeast coast of New Guinea, whereas others were manufactured from inland materials. These findings represent the oldest securely dated pottery from an archaeological context on the island of New Guinea. Additionally, the pottery comes from the interior, suggesting the movements of people and technological practices, as well as objects at this time. The antiquity of the Wañelek pottery is coincident with the expansion of Lapita pottery in the Western Pacific. Such occupation also occurs at the same time that changes have been identified in subsistence strategies in the archaeological record at Kuk Swamp suggesting a possible link between the two.

  17. Pliocene environments and climates in the western United States

    USGS Publications Warehouse

    Thompson, R.S.

    1991-01-01

    The available evidence from the western United States suggests that the climate of the Early and Middle Pliocene (prior to ???2.4 Ma) was less seasonal (more equable) and generally more humid than now. Along the Pacific coast, summer drought was less pronounced than today. In the interior of the Pacific Northwest rainfall was more abundant and mild winter temperatures prevailed across much of the High Plains. In the Northwestern interior, a trend toward drier conditions began after ???4 Ma, although there may have been short periods of relatively humid conditions after this time. The period between 2.5 or 2.4-2.0 Ma was drier than earlier in the Pliocene throughout the American West, and apparently colder in many regions, although the occurrence of land tortoises as far north as Kansas may indicate intermittent frost-free conditions during this interval. After ???2.0 Ma conditions became warmer and more humid. The general climatic trends in the terrestrial data parallel fluctuations seen in North Pacific and in Oxygen Isotopic records of global glacial fluctuations. Global Climate Model (GCM) simulations of the regional effects of Late Cenozoic uplift and mountain-building are generally in accord with the nature, direction, and amplitude of differences between Pliocene and modern climates. ?? 1991.

  18. Geochemistry and magnetic sediment distribution at the western boundary upwelling system of southwest Atlantic

    NASA Astrophysics Data System (ADS)

    Cruz, Anna P. S.; Barbosa, Catia F.; Ayres-Neto, Arthur; Munayco, Pablo; Scorzelli, Rosa B.; Amorim, Nívea Santos; Albuquerque, Ana L. S.; Seoane, José C. S.

    2018-02-01

    In order to investigate the chemical and magnetic characteristics of sediments of the western boundary upwelling system of Southwest Atlantic we analyzed magnetic susceptibility, grain size distribution, total organic carbon, heavy mineral abundance, Fe associated with Mössbauer spectra, and Fe and Mn of pore water to evaluate the deposition patterns of sediments. Four box-cores were collected along a cross-shelf transect. Brazil Current and coastal plume exert a primary control at the inner and outer shelf cores, which exhibited similar depositional patterns characterized by a high abundance of heavy minerals (mean 0.21% and 0.08%, respectively) and very fine sand, whereas middle shelf cores presented low abundances of heavy minerals (mean 0.03%) and medium silt. The inner shelf was dominated by sub-angular grains, while in middle and outer shelf cores well-rounded grains were found. The increasing Fe3+:Fe2+ ratio from the inner to the outer shelf reflects farther distance to the sediment source. The outer shelf presented well-rounded minerals, indicating abrasive processes as a result of transport by the Brazil Current from the source areas. In the middle shelf, cold-water intrusion of the South Atlantic Central Water contributes to the primary productivity, resulting in higher deposition of fine sediment and organic carbon accumulation. The high input of organic carbon and the decreased grain size are indicative of changes in the hydrodynamics and primary productivity fueled by the western boundary upwelling system, which promotes loss of magnetization due to the induction of diagenesis of iron oxide minerals.

  19. Two-stage Uplift of Granite-Gneiss-Migmatite Complex (GGMC) of Çataldaǧ Core Complex (Western Anatolia, Turkey): the role of detachment faults on uplift processes

    NASA Astrophysics Data System (ADS)

    Kamaci, Omer; Altunkaynak, Safak

    2016-04-01

    The most recently identified core complex of western Anatolia (Turkey), the Çataldaǧ Core Complex (ÇCC) consists of a granite-gneiss-migmatite complex (GGMC) representing deep crustal rocks of NW Turkey and a shallow level granodioritic body (ÇG: Çataldaǧ granodiorite). The GGMC is Latest Eocene-Early Oligocene and ÇG is Early Miocene in age, and both were exhumed in the footwall of the Çataldaǧ Detachment Fault Zone (ÇDFZ) in the Early Miocene. On the basis of correlation of age data and the closure temperatures of zircon, monazite, muscovite, biotite and K-feldspar, the T-time history of GGMC reveals that GGMC has experienced at least two stages of cooling and uplift, from 33.8 to 30.1 Ma and 21.3 to 20.7 Ma. In stage I, from 33.8 to 30.1 Ma, the cooling rate of GGMC was relatively slow (35°C/my) however cooling rate increase dramatically to ≥500°C/my in stage II between 21.3 and 20.7 Ma. T-time history also indicate that GGMC was elevated to the final location in at least 8-13 My according to the monazite and zircon and mica ages obtained from the same rock. Rapid slab rollback at the Hellenic trench at ca. 23 Ma may have increased extension rates leading to the development of detachment faults (i.e. ÇDFZ), core complexes and associated syn-extensional granitoids in Western Anatolia and the Aegean extensional province.

  20. Global Warming Implications of the Use of By-Products and Recycled Materials in Western Australia’s Housing Sector

    PubMed Central

    Lawania, Krishna; Sarker, Prabir; Biswas, Wahidul

    2015-01-01

    Western Australia’s housing sector is growing rapidly and around half a million houses are expected to be built by 2030, which not only will result in increased energy and resources demand but will have socio-economic impacts. Majority of Western Australians live in detached houses made of energy intensive clay bricks, which have a high potential to generate construction and demolition (C&D) waste. Therefore, there is a need to look into the use of alternative materials and construction methods. Due to Western Australia’s temperate climate, concrete could not only offer a comfortable living space but an operational energy saving also can be achieved. This paper has assessed the global warming implications of cast in-situ concrete sandwich wall system as an alternative to clay brick walls (CBW) with partial replacement of cement in concrete with by-products such as fly ash (FA) and ground granulated blast furnace slag (GGBFS), natural aggregate (NA) with recycled crushed aggregate (RCA), natural sand (NS) with manufactured sand (MS) and, polyethylene terephthalate (PET) foam core as a replacement to polystyrene core for construction of a typical 4 × 2 × 2 detached house in Perth. Life cycle management (LCM) approach has been used to determine global warming reduction benefits due to the use of available by-products and recycled materials in Western Australian houses.

  1. Mantle updrafts and mechanisms of oceanic volcanism.

    PubMed

    Anderson, Don L; Natland, James H

    2014-10-14

    Convection in an isolated planet is characterized by narrow downwellings and broad updrafts--consequences of Archimedes' principle, the cooling required by the second law of thermodynamics, and the effect of compression on material properties. A mature cooling planet with a conductive low-viscosity core develops a thick insulating surface boundary layer with a thermal maximum, a subadiabatic interior, and a cooling highly conductive but thin boundary layer above the core. Parts of the surface layer sink into the interior, displacing older, colder material, which is entrained by spreading ridges. Magma characteristics of intraplate volcanoes are derived from within the upper boundary layer. Upper mantle features revealed by seismic tomography and that are apparently related to surface volcanoes are intrinsically broad and are not due to unresolved narrow jets. Their morphology, aspect ratio, inferred ascent rate, and temperature show that they are passively responding to downward fluxes, as appropriate for a cooling planet that is losing more heat through its surface than is being provided from its core or from radioactive heating. Response to doward flux is the inverse of the heat-pipe/mantle-plume mode of planetary cooling. Shear-driven melt extraction from the surface boundary layer explains volcanic provinces such as Yellowstone, Hawaii, and Samoa. Passive upwellings from deeper in the upper mantle feed ridges and near-ridge hotspots, and others interact with the sheared and metasomatized surface layer. Normal plate tectonic processes are responsible both for plate boundary and intraplate swells and volcanism.

  2. Mantle updrafts and mechanisms of oceanic volcanism

    NASA Astrophysics Data System (ADS)

    Anderson, Don L.; Natland, James H.

    2014-10-01

    Convection in an isolated planet is characterized by narrow downwellings and broad updrafts-consequences of Archimedes' principle, the cooling required by the second law of thermodynamics, and the effect of compression on material properties. A mature cooling planet with a conductive low-viscosity core develops a thick insulating surface boundary layer with a thermal maximum, a subadiabatic interior, and a cooling highly conductive but thin boundary layer above the core. Parts of the surface layer sink into the interior, displacing older, colder material, which is entrained by spreading ridges. Magma characteristics of intraplate volcanoes are derived from within the upper boundary layer. Upper mantle features revealed by seismic tomography and that are apparently related to surface volcanoes are intrinsically broad and are not due to unresolved narrow jets. Their morphology, aspect ratio, inferred ascent rate, and temperature show that they are passively responding to downward fluxes, as appropriate for a cooling planet that is losing more heat through its surface than is being provided from its core or from radioactive heating. Response to doward flux is the inverse of the heat-pipe/mantle-plume mode of planetary cooling. Shear-driven melt extraction from the surface boundary layer explains volcanic provinces such as Yellowstone, Hawaii, and Samoa. Passive upwellings from deeper in the upper mantle feed ridges and near-ridge hotspots, and others interact with the sheared and metasomatized surface layer. Normal plate tectonic processes are responsible both for plate boundary and intraplate swells and volcanism.

  3. Mantle updrafts and mechanisms of oceanic volcanism

    PubMed Central

    Anderson, Don L.; Natland, James H.

    2014-01-01

    Convection in an isolated planet is characterized by narrow downwellings and broad updrafts—consequences of Archimedes’ principle, the cooling required by the second law of thermodynamics, and the effect of compression on material properties. A mature cooling planet with a conductive low-viscosity core develops a thick insulating surface boundary layer with a thermal maximum, a subadiabatic interior, and a cooling highly conductive but thin boundary layer above the core. Parts of the surface layer sink into the interior, displacing older, colder material, which is entrained by spreading ridges. Magma characteristics of intraplate volcanoes are derived from within the upper boundary layer. Upper mantle features revealed by seismic tomography and that are apparently related to surface volcanoes are intrinsically broad and are not due to unresolved narrow jets. Their morphology, aspect ratio, inferred ascent rate, and temperature show that they are passively responding to downward fluxes, as appropriate for a cooling planet that is losing more heat through its surface than is being provided from its core or from radioactive heating. Response to doward flux is the inverse of the heat-pipe/mantle-plume mode of planetary cooling. Shear-driven melt extraction from the surface boundary layer explains volcanic provinces such as Yellowstone, Hawaii, and Samoa. Passive upwellings from deeper in the upper mantle feed ridges and near-ridge hotspots, and others interact with the sheared and metasomatized surface layer. Normal plate tectonic processes are responsible both for plate boundary and intraplate swells and volcanism. PMID:25201992

  4. Soil data for a thermokarst bog and the surrounding permafrost plateau forest, located at Bonanza Creek Long Term Ecological Research Site, Interior Alaska

    USGS Publications Warehouse

    Manies, Kristen L.; Fuller, Christopher C.; Jones, Miriam C.; Waldrop, Mark P.; McGeehin, John P.

    2017-01-19

    Peatlands play an important role in boreal ecosystems, storing a large amount of soil organic carbon. In northern ecosystems, collapse-scar bogs (also known as thermokarst bogs) often form as the result of ground subsidence following permafrost thaw. To examine how ecosystem carbon balance changes with the loss of permafrost, we measured carbon and nitrogen storage within a thermokarst bog and the surrounding forest, which continues to have permafrost. These sites are a part of the Bonanza Creek Long Term Ecological Research (LTER) site and are located within Interior Alaska. Here, we report on methods used for core collection analysis as well as the cores’ physical, chemical, and descriptive properties.

  5. KSC-2011-6513

    NASA Image and Video Library

    2011-08-18

    CAPE CANAVERAL, Fla. -- Technicians lower NASA's twin Gravity Recovery and Interior Laboratory (GRAIL) spacecraft into place atop a United Launch Alliance Delta II rocket on Space Launch Complex 17B at Cape Canaveral Air Force Station in Florida. The lunar probes are attached to a spacecraft adapter ring in their side-by-side launch configuration and wrapped in plastic to prevent contamination outside the clean room. The spacecraft will fly in tandem orbits around the moon for several months to measure its gravity field. GRAIL's primary science objectives are to determine the structure of the lunar interior, from crust to core, and to advance understanding of the thermal evolution of the moon. Launch is scheduled for Sept. 8. For more information, visit www.nasa.gov/grail. Photo credit: NASA/Kim Shiflett

  6. KSC-2011-6103

    NASA Image and Video Library

    2011-07-30

    CAPE CANAVERAL, Fla. -- Preparations are under way to begin two days of fueling activities on NASA's twin Gravity Recovery and Interior Laboratory lunar spacecraft in the Hazardous Processing Facility (HPF) at Astrotech Space Operation's payload processing facility in Titusville, Fla. GRAIL will fly in tandem orbits around the moon for several months to measure its gravity field. GRAIL's primary science objectives are to determine the structure of the lunar interior, from crust to core, and to advance understanding of the thermal evolution of the moon. Launch aboard a United Launch Alliance Delta II rocket from Space Launch Complex 17B on Cape Canaveral Air Force Station is scheduled for Sept. 8. For more information, visit http://www.nasa.gov/grail. Photo credit: NASA/Charisse Nahser

  7. Cooling of neutron stars

    NASA Technical Reports Server (NTRS)

    Pethick, C. J.

    1992-01-01

    It is at present impossible to predict the interior constitution of neutron stars based on theory and results from laboratory studies. It has been proposed that it is possible to obtain information on neutron star interiors by studying thermal radiation from their surfaces, because neutrino emission rates, and hence the temperature of the central part of a neutron star, depend on the properties of dense matter. The theory predicts that neutron stars cool relatively slowly if their cores are made up of nucleons, and cool faster if the matter is in an exotic state, such as a pion condensate, a kaon condensate, or quark matter. This view has recently been questioned by the discovery of a number of other processes that could lead to copious neutrino emission and rapid cooling.

  8. Core dynamics and the nutations of the Earth.

    NASA Astrophysics Data System (ADS)

    Dehant, V. M. A.; Laguerre, R.; Rekier, J.; Rivoldini, A.; Trinh, A.; Triana, A. S.; Van Hoolst, T.; Zhu, P.

    2016-12-01

    We here present an overview of the recent activities within the project RotaNut - Rotation and Nutation of a Wobbly Earth, an ERC Advanced Grant funding from the European Research Council. We have recomputed the Basic Earth Parameters from recent VLBI series and we interpret them in terms of physics of the Earth's deep interior. This includes updates of the nutational constraints on Earth's internal magnetic field and inner core viscosity, as well as of the coupling constants at the core-mantle boundary (CMB) and inner core boundary ICB. We have explored on simplified Earth models the interactions between rotational and gravito-inertial modes. With the help of numerical simulations, we have also addressed the coupling between the global rotation and the inertial waves in the fluid core through parametric instabilities. Special interests have been given to the influence of the inner core onto the stability properties of the liquid core and the large scale formation in the turbulent flow through inverse cascade of energy. The role of precession and nutation forcing for the liquid core is characterized as well as the interaction between the Free Core Nutation (in the fluid core community called the tilt-over mode) and the inertial waves. This research represents the first steps in the project RotaNut financed by the European Research Council under ERC Advanced Grant 670874 for 2015-2020.

  9. Kinetic and Thermodynamic Characterization of the Cobalt and Manganese Oxyhydroxide Cores Formed in Horse Spleen Ferritin

    NASA Technical Reports Server (NTRS)

    Zhang, Bo; Harb, John N.; Davis, Robert C.; Kim, Jae-Woo; Chu, Sang-Hyon; Choi, Sang; Miller, Tim; Watt, Gerald D.

    2004-01-01

    Horse spleen ferritin (HoSF) containing 800-1500 cobalt or 250-1200 manganese atoms as Co(O)OH and Mn(O)OH mineral cores within the HoSF interior (Co-HoSF and Mn-HoSF) was synthesized, and the chemical reactivity, kinetics of reduction, and the reduction potentials were measured. Microcoulometric and chemical reduction of HoSF containing the M(O)OH mineral core (M = Co or Mn) was rapid and quantitative with a reduction stoichiometry of 1.05+/-0.10 e/M forming a stable M(OH)2 mineral core. At pH 9.0, ascorbic acid (AH2), a two-electron reductant, effectively reduced the mineral cores; however, the reaction was incomplete and rapidly reached equilibrium. The addition of excess AH2 shifted the reaction to completion with a M(3+)/AH2 stoichiometry of 1.9-2.1, consistent with a single electron per metal atom reduction. The rate of reaction between M(0)OH and excess AH2 was measured by monitoring the decrease in mineral core absorbance with time. The reaction was first order in each reactant with second-order rate constants of 0.53 and 4.74/M/min, respectively, for Co- and Mn-HoSF at pH 9.0. From the variation of absorbance with increasing AH2 concentration, equilibrium constants at pH 9.0 of 5.0+/-1.9 for Co-HoSF and 2.9+/-0.9 for Mn-HoSF were calculated for 2M(O)OH + AH2 = 2M(OH)2 f D, where AH2 and D are ascorbic acid and dehydroascorbic acid, respectively. Consistent with these equilibrium constants, the standard potential for the reduction of Co(III)-HoSF is 42 mV more positive than that of the ascorbic acid reaction, while the standard potential of Mn(III)-HoSF is 27 mV positive relative to AH2. Fe(2+) in solution with Co- and Mn-HoSF under anaerobic conditions was oxidized to form Fe(O)OH within the HoSF interior, resulting in partial displacement of the Co or Mn by iron.

  10. Mercury's Interior from MESSENGER Radio Science Data

    NASA Astrophysics Data System (ADS)

    Genova, A.; Mazarico, E.; Goossens, S. J.; Lemoine, F. G.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2017-12-01

    The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft provided precise radio tracking data in orbit about Mercury for more than 4 years, from March 2011 to April 2015. These geodetic measurements enable us to investigate the interior structure of the planet from the inner core to the crust. The first three years of radio data allowed us to determine the gravity field of Mercury with a resolution of 150 km in the northern hemisphere (degree and order 50 in spherical harmonics) since the periapsis was located at higher latitudes (>65˚N) and 200-500 km altitudes. The comparison of this gravity solution with Mercury's topography, which was retrieved by using over 25 million individual measurements of the Mercury Laser Altimeter (MLA), resulted in a preliminary map of the crustal thickness of the planet. However, those results were limited by the resolution of the gravity field since the topography was defined in spherical harmonics up to degree and order 125. The last year of the MESSENGER extended mission was dedicated to a low-altitude campaign, where the spacecraft periapsis was maintained at altitudes between 25 and 100 km. The radio data collected during this mission phase allowed us to significantly improve the resolution of the gravity field locally in the northern hemisphere up to degree and order 100 in spherical harmonics. We present the gravity anomalies and crustal thickness maps that lead to a better understanding on the formation and evolution of specific regions. We present our estimated orientation model, which slightly differs from the solutions that were obtained by using Earth-based radar measurements and the co-registration of MESSENGER imaging and altimetry data. These previous estimates provide a direct measurement of the surface response, whereas the orientation model from gravity is more sensitive to the inner and outer core. A discrepancy between core and surface obliquities may provide fundamental information on the status of the outer core and the presence of a solid inner core. We also present the latest solution of the tidal Love number k2 that enables us to constrain the basal temperature and rigidity of the outer molten core.

  11. Ductile and Brittle Neogene Deformation of Late Permian Orthogneiss in the Northern Ailao Shan-Red River Shear Zone: View from the Xuelong Shan Block

    NASA Astrophysics Data System (ADS)

    Wintsch, R. P.; Yi, D.; Yi, K.; Wang, Q. F.; Wang, G. H.

    2014-12-01

    The orthogneisses in the core of the Xuelong Shan block are surrounded by ductile and then brittle fault rocks. This lens-shape block is in fault contact with Triassic marbles on the eastern margin and Jurassic-Cretaceous mudstones on the western margin. The rocks in the core of the Xuelong Shan block contain multiply foliated feldspathic orthogneisses with local amphibolites, largely overprinted by protomylonitic deformation. Foliation strengthens to the east to become mylonites and ultramylonites, with a 30 m wide zone of loosely cemented fault breccia adjacent to brittlely faulted Triassic marbles. In contrast, the rocks to the west are dominated by brittle deformation, with mylonites becoming cataclasites and then breccias facing the mudstones to the east. Well-foliated phyllonites are locally present within the cataclasites. Early S1 gneissosity striking ENE are recognized only in the interior protomylonite. In the east, the dominate mylonitic S2 foliation strikes 340° with a moderate dip to the east, and an L2 mineral stretching lineation plunges gently north. However, in the west S2 cleavage is transposed into a NNW trending schistosity that dips steeply to the ENE, with down-dip mineral stretching lineations. Whole rock chemistry indicates a granitic to granodioritic protolith for all the rocks including the ultramylonites, but also suggests the progressive loss of alkalis with increasing deformation. Trace element compositions show these rocks lie in the volcanic arc/syn-collisional granite field. U-Pb SHRIMP ages show an Early Triassic age for these granite, with possible Middle Permian inheritance in some cores. These ages are consistent with the period of the closure of the northern Paleo-Tethys ocean. Metamorphic rim ages of ~ 30 Ma record a small amount of zircon dissolution/precipitation probably associated with the Oligocene ductile deformation that produced the upper greenschist facies mylonites. These results support the geologic history of the ASRRSZ based on data obtained in the southern Diancang Shan block. Permian granitoids were intruded and ductily deformed in the Early Triassic. The left lateral shearing that brought these blocks to the surface was delayed until the Neogene extrusion of the Indochina block.

  12. Old stories and lost pieces of the Eastern Mediterranean puzzle: a new approach to the tectonic evolution of the Western Anatolia and the Aegean Sea

    NASA Astrophysics Data System (ADS)

    Yaltırak, Cenk; Engin Aksu, Ali; Hall, Jeremy; Elitez, İrem

    2015-04-01

    During the last 20 or so years, the tectonic evolution of Aegean Sea and Western Anatolia has been dominantly explained by back-arc extension and escape tectonics along the North Anatolian Fault. Various datasets have been considered in the construction of general tectonic models, including the geometry of fault patterns, paleomagnetic data, extensional directions of the core complexes, characteristic changes in magmatism and volcanism, the different sense of Miocene rotation between the opposite sides of the Aegean Sea, and the stratigraphy and position of the Miocene and Pliocene-Quaternary basins. In these models, the roles of the Burdur-Fethiye Shear Zone, the Trakya-Eskişehir Fault Zone, the Anaximander Mountains and Isparta Angle have almost never been taken into consideration. The holistic evaluation of numerous land and marine researches in the Aegean Sea and western Anatolia suggest the following evolutionary stages: 1. during the early Miocene, Greece and western Anatolia were deformed under the NE-SW extensional tectonics associated with the back-arc extension, when core complexes and supra-detachment basins developed, 2. following the collision of the Anaximander Mountains and western Anatolia in early Miocene , the Isparta Angle locked this side of the western arc by generating a triangle-shaped compressional structure, 3. while the Isparta Angle penetrated into the Anatolia, the NE-striking Burdur-Fethiye Shear Zone in the west and NW-striking Trakya-Eskişehir Fault Zone in the north developed along the paleo-tectonic zones , 4. the formation of these two tectonic structures allowed the counterclockwise rotation of the western Anatolia in the middle Miocene and this rotation removed the effect of the back-arc extension on the western Anatolian Block, 5. the counterclockwise rotation developed with the early westward escape of the Western Anatolian reached up to 35-40o and Trakya-Eskişehir Fault Zone created a total dextral displacement of about 200 km. Therefore the original NE-SW extension records on the core complexes rotated to the N-S orientation and replace 45o in reference to the core complexes in Greece, 6. During this stage, the left-lateral shear along the Burdur-Fethiye Shear Zone indicates the southern part of the counterclockwise rotation. 7. The North Anatolian Fault started to form as the result of the collision of the Arabian Microplate and the Eurasian Plate in the late Miocene. This continental transform fault propagated into the Marmara Region in the late Pliocene. Its late westward escape by cutting the Trakya-Eskişehir Fault Zone on three points generates its transportation through Trakya-Eskişehir Fault Zone splays. 8. During the Miocene, while Greece was rotating 20o clockwise and continuing to be shaped by the NW-SE normal faults, which were formed as a result of back-arc tectonic, the late westward escape of the Anatolia changed the orientation of the NEE-SWW striking oblique-extensional fault-controlled Miocene basins to NE-SW direction. The rotational E-W basins, which had developed by the North Anatolian Fault tectonics, superimposed with these Miocene basins .

  13. Microcapsules with three orthogonal reactive sites

    PubMed Central

    Mason, Brian P.; Hira, Steven M.; Strouse, Geoffrey F.; McQuade, D. Tyler

    2009-01-01

    Polymeric microcapsules containing reactive sites on the shell surface and two orthogonally reactive polymers encapsulated within the interior are selectively labeled. The capsules provide three spatially separate and differentially reactive sites. Confocal fluorescence microscopy is used to characterize the distribution of labels. Polymers encapsulated are distributed homogeneously within the core and do not interact with the shell even when oppositely charged. PMID:19254010

  14. Spatiotemporal patterns of ring-width variability in the northern interior west

    Treesearch

    R. Justin DeRose; John D. Shaw; James N. Long

    2015-01-01

    A fundamental goal of forest biogeography is to understand the factors that drive spatiotemporal variability in forest growth across large areas (e.g., states or regions). The ancillary collection of increment cores as part of the IW FIA Program represents an important non-traditional role for the development of unprecedented data sets. Individual-tree growth data from...

  15. InSight Prelaunch Briefing

    NASA Image and Video Library

    2018-05-03

    Tim Dunn, launch director, NASA’s Launch Services Program, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  16. InSight Prelaunch Briefing

    NASA Image and Video Library

    2018-05-03

    A video showing NASA's InSight spacecraft separating from the Atlas V rocket is seen during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  17. InSight Prelaunch Briefing

    NASA Image and Video Library

    2018-05-03

    Stu Spath, InSight program manager, Lockheed Martin Space, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  18. InSight Prelaunch Briefing

    NASA Image and Video Library

    2018-05-03

    Andy Klesh, MarCO chief engineer, NASA JPL, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  19. InSight Prelaunch Briefing

    NASA Image and Video Library

    2018-05-03

    Tom Hoffman, InSight project manager, NASA JPL, right, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

  20. InSight Prelaunch

    NASA Image and Video Library

    2018-05-04

    A heavy fog rolls in as the United Launch Alliance (ULA) Atlas-V rocket with NASA's InSight spacecraft onboard awaits launch, Friday, May 4, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

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