Science.gov

Sample records for allan hills ice

  1. Uranium series dating of Allan Hills ice

    NASA Technical Reports Server (NTRS)

    Fireman, E. L.

    1986-01-01

    Uranium-238 decay series nuclides dissolved in Antarctic ice samples were measured in areas of both high and low concentrations of volcanic glass shards. Ice from the Allan Hills site (high shard content) had high Ra-226, Th-230 and U-234 activities but similarly low U-238 activities in comparison with Antarctic ice samples without shards. The Ra-226, Th-230 and U-234 excesses were found to be proportional to the shard content, while the U-238 decay series results were consistent with the assumption that alpha decay products recoiled into the ice from the shards. Through this method of uranium series dating, it was learned that the Allen Hills Cul de Sac ice is approximately 325,000 years old.

  2. Carbon-14 ages of Allan Hills meteorites and ice

    NASA Technical Reports Server (NTRS)

    Fireman, E. L.; Norris, T.

    1982-01-01

    Allan Hills is a blue ice region of approximately 100 sq km area in Antarctica where many meteorites have been found exposed on the ice. The terrestrial ages of the Allan Hills meteorites, which are obtained from their cosmogenic nuclide abundances are important time markers which can reflect the history of ice movement to the site. The principal purpose in studying the terrestrial ages of ALHA meteorites is to locate samples of ancient ice and analyze their trapped gas contents. Attention is given to the C-14 and Ar-39 terrestrial ages of ALHA meteorites, and C-14 ages and trapped gas compositions in ice samples. On the basis of the obtained C-14 terrestrial ages, and Cl-36 and Al-26 results reported by others, it is concluded that most ALHA meteorites fell between 20,000 and 200,000 years ago.

  3. The natural thermoluminescence of meteorites. V - Ordinary chondrites at the Allan Hills ice fields

    NASA Technical Reports Server (NTRS)

    Benoit, Paul H.; Sears, Hazel; Sears, Derek W. G.

    1993-01-01

    Natural thermoluminescence (TL) data have been obtained for 167 ordinary chondrites from the ice fields in the vicinity of the Allan Hills in Victoria Land, Antarctica, in order to investigate their thermal and radiation history, pairing, terrestrial age, and concentration mechanisms. Natural TL values for meteorites from the Main ice field are fairly low, while the Farwestern field shows a spread with many values 30-80 krad, suggestive of less than 150-ka terrestrial ages. There appear to be trends in TL levels within individual ice fields which are suggestive of directions of ice movement at these sites during the period of meteorite concentration. These directions seem to be confirmed by the orientations of elongation preserved in meteorite pairing groups. The proportion of meteorites with very low natural TL levels at each field is comparable to that observed at the Lewis Cliff site and for modern non-Antarctic falls and is also similar to the fraction of small perihelia orbits calculated from fireball and fall observations. Induced TL data for meteorites from the Allan Hills confirm trends which show that a select group of H chondrites from the Antarctic experienced a different extraterrestrial thermal history to that of non-Antarctic H chondrites.

  4. Atmospheric composition 1 million years ago from blue ice in the Allan Hills, Antarctica

    PubMed Central

    Higgins, John A.; Kurbatov, Andrei V.; Spaulding, Nicole E.; Brook, Ed; Introne, Douglas S.; Chimiak, Laura M.; Yan, Yuzhen; Mayewski, Paul A.; Bender, Michael L.

    2015-01-01

    Here, we present direct measurements of atmospheric composition and Antarctic climate from the mid-Pleistocene (∼1 Ma) from ice cores drilled in the Allan Hills blue ice area, Antarctica. The 1-Ma ice is dated from the deficit in 40Ar relative to the modern atmosphere and is present as a stratigraphically disturbed 12-m section at the base of a 126-m ice core. The 1-Ma ice appears to represent most of the amplitude of contemporaneous climate cycles and CO2 and CH4 concentrations in the ice range from 221 to 277 ppm and 411 to 569 parts per billion (ppb), respectively. These concentrations, together with measured δD of the ice, are at the warm end of the field for glacial–interglacial cycles of the last 800 ky and span only about one-half of the range. The highest CO2 values in the 1-Ma ice fall within the range of interglacial values of the last 400 ka but are up to 7 ppm higher than any interglacial values between 450 and 800 ka. The lowest CO2 values are 30 ppm higher than during any glacial period between 450 and 800 ka. This study shows that the coupling of Antarctic temperature and atmospheric CO2 extended into the mid-Pleistocene and demonstrates the feasibility of discontinuously extending the current ice core record beyond 800 ka by shallow coring in Antarctic blue ice areas. PMID:25964367

  5. The Natural Thermoluminescence of Meteorites. Part 5; Ordinary Chondrites at the Allan Hills Ice Fields

    NASA Technical Reports Server (NTRS)

    Benoit, Paul H.; Sears, Hazel; Sears, Derek W. G.

    1993-01-01

    Natural thermoluminescence (TL) data have been obtained for 167 ordinary chondrites from the ice fields in the vicinity of the Allan Hills in Victoria Land, Antarctica, in order to investigate their thermal and radiation history, pairing, terrestrial age, and concentration mechanisms. Using fairly conservative criteria (including natural and induced TL, find location, and petrographic data), the 167 meteorite fragments are thought to represent a maximum of 129 separate meteorites. Natural TL values for meteorites from the Main ice field are fairly low (typically 5-30 krad, indicative of terrestrial ages of approx. 400 ka), while the Far western field shows a spread with many values 30-80 krad, suggestive of less then 150-ka terrestrial ages. There appear to be trends in TL levels within individual ice fields which are suggestive of directions of ice movement at these sites during the period of meteorite concentration. These directions seem to be confirmed by the orientations of elongation preserved in meteorite pairing groups. The proportion of meteorites with very low natural TL levels (less then 5 krad) at each field is comparable to that observed at the Lewis Cliff site and for modern non-Antarctic falls and is also similar to the fraction of small perihelia (less then 0.85 AU) orbits calculated from fireball and fall observations. Induced TL data for meteorites from the Allan Hills confirm trends observed for meteorites collected during the 1977/1978 and 1978/1979 field seasons which show that a select group of H chondrites from the Antarctic experienced a different extraterrestrial thermal history to that of non-Antarctic H chondrites.

  6. Age of Allan Hills 82102, a meteorite found inside the ice

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Jull, A. J. T.; Bonani, G.; Suter, M.; Woelfli, W.

    1989-01-01

    The terrestrial age of a meteorite that was recovered from below the surface of Antarctic ice is reported, and it is argued that this represents a measurement of the age of the ice itself. The cosmogenic radionuclides Be-10, C-14, Al-26, Cl-36, and Mn-53 are measured in the meteorite and Be-10 and Cl-36 in the ice. A terrestrial age of 11,000 yr is obtained for the meteorite, which suggests that the snow accumulation area where it fell was only a few tens of km away.

  7. Exposure and terrestrial ages of four Allan Hills Antarctic meteorites

    NASA Technical Reports Server (NTRS)

    Kirsten, T.; Ries, D.; Fireman, E. L.

    1978-01-01

    Terrestrial ages of meteorites are based on the amount of cosmic-ray-produced radioactivity in the sample and the number of observed falls that have similar cosmic-ray exposure histories. The cosmic-ray exposures are obtained from the stable noble gas isotopes. Noble gas isotopes are measured by high-sensitivity mass spectrometry. In the present study, the noble gas contents were measured in four Allan Hill meteorites (No. 5, No. 6, No. 7, and No. 8), whose C-14, Al-26, and Mn-53 radioactivities are known. These meteorites are of particular interest because they belong to a large assemblage of distinct meteorites that lie exposed on a small (110 sq km) area of ice near the Allan Hills.

  8. Noble gases in twenty Yamato H-chondrites: Comparison with Allan Hills chondrites and modern falls

    NASA Technical Reports Server (NTRS)

    Loeken, TH.; Scherer, P.; Schultz, L.

    1993-01-01

    Concentration and isotopic composition of noble gases have been measured in 20 H-chrondrites found on the Yamato Mountains ice fields in Antarctica. The distribution of exposure ages as well as of radiogenic He-4 contents is similar to that of H-chrondrites collected at the Allan Hills site. Furthermore, a comparison of the noble gas record of Antarctic H-chrondrites and finds or falls from non-Antarctic areas gives no support to the suggestion that Antarctic H-chrondrites and modern falls derive from differing interplanetary meteorite populations.

  9. Nannobacterial alteration of pyroxenes in martian meteorite Allan Hills 84001

    NASA Astrophysics Data System (ADS)

    Folk, Robert L.; Taylor, Lawrence A.

    2002-08-01

    In martian meteorite Allan Hills (ALH) 84001, this scanning electron microscope study was focused on the ferromagnesian minerals, which are extensively covered with nanometer-size bodies mainly 30-100 nm in diameter. These bodies range from spheres to ovoids to caterpillar shapes and resemble, both in size and shape, nannobacteria that attack weathered rocks on Earth and that can be cultured. Dense colonies alternate with clean, smooth cleavage surfaces, possibly formed later. Statistical study shows that the distribution of presumed nannobacteria is very clustered. In addition to the small bodies, there are a few occurrences of ellipsoidal 200-400 nm objects, that are within the lower size range of "normal" earthly bacteria. We conclude that the nanobodies so abundant in ALH 84001 are indeed nannobacteria, confirming the initial assertion of McKay et al. (1996). However, whether these bodies originated on Mars or are Antarctic contamination remains a valid question.

  10. Petrogenetic relationship between Allan Hills 77005 and other achondrites

    NASA Technical Reports Server (NTRS)

    Mcsween, H. Y., Jr.; Taylor, L. A.; Stolper, E. M.; Muntean, R. A.; Okelley, G. D.; Eldridge, J. S.; Biswas, S.; Ngo, H. T.; Lipschutz, M. E.

    1979-01-01

    The paper presents chemical and petrologic data relating the Allan Hills (ALHA) 77005 achondrite from Antarctica and explores their petrogenetic relationship with the shergottites. Petrologic similarities with the latter in terms of mineralogy, oxidation state, inferred source region composition, and shock ages suggest a genetic relationship, also indicated by volatile to involatile element ratios and abundances of other trace elements. ALHA 77005 may be a cumulate crystallized from a liquid parental to materials from which the shergottites crystallized or a sample of peridotite from which shergottite parent liquids were derived. Chemical similarities with terrestrial ultramafic rocks suggest that it provides an additional sample of the only other solar system body with basalt source origins chemically similar to the upper earth mantle.

  11. The History of Allan Hills 84001 Revised: Multiple Shock Events

    NASA Technical Reports Server (NTRS)

    Treiman, Allan H.

    1998-01-01

    The geologic history of Martian meteorite Allan Hills (ALH) 84001 is more complex than previously recognized, with evidence for four or five crater-forming impacts onto Mars. This history of repeated deformation and shock metamorphism appears to weaken some arguments that have been offered for and against the hypothesis of ancient Martian life in ALH 84001. Allan Hills 84001 formed originally from basaltic magma. Its first impact event (I1) is inferred from the deformation (D1) that produced the granular-textured bands ("crush zones") that transect the original igneous fabric. Deformation D1 is characterized by intense shear and may represent excavation or rebound flow of rock beneath a large impact crater. An intense thermal metamorphism followed D1 and may be related to it. The next impact (I2) produced fractures, (Fr2) in which carbonate "pancakes" were deposited and produced feldspathic glass from some of the igneous feldspars and silica. After I2, carbonate pancakes and globules were deposited in Fr2 fractures and replaced feldspathic glass and possibly crystalline silicates. Next, feldspars, feldspathic glass, and possibly some carbonates were mobilized and melted in the third impact (I3). Microfaulting, intense fracturing, and shear are also associated with 13. In the fourth impact (I4), the rock was fractured and deformed without significant heating, which permitted remnant magnetization directions to vary across fracture surfaces. Finally, ALH 84001 was ejected from Mars in event I5, which could be identical to I4. This history of multiple impacts is consistent with the photogeology of the Martian highlands and may help resolve some apparent contradictions among recent results on ALH 84001. For example, the submicron rounded magnetite grains in the carbonate globules could be contemporaneous with carbonate deposition, whereas the elongate magnetite grains, epitaxial on carbonates, could be ascribed to vapor-phase deposition during I3.

  12. Investigations into an unknown organism on the martian meteorite Allan Hills 84001

    NASA Technical Reports Server (NTRS)

    Steele, A.; Goddard, D. T.; Stapleton, D.; Toporski, J. K.; Peters, V.; Bassinger, V.; Sharples, G.; Wynn-Williams, D. D.; McKay, D. S.

    2000-01-01

    Examination of fracture surfaces near the fusion crust of the martian meteorite Allan Hills (ALH) 84001 have been conducted using scanning electron microscopy (SEM) and atomic force microscopy (AFM) and has revealed structures strongly resembling mycelium. These structures were compared with similar structures found in Antarctic cryptoendolithic communities. On morphology alone, we conclude that these features are not only terrestrial in origin but probably belong to a member of the Actinomycetales, which we consider was introduced during the Antarctic residency of this meteorite. If true, this is the first documented account of terrestrial microbial activity within a meteorite from the Antarctic blue ice fields. These structures, however, do not bear any resemblance to those postulated to be martian biota, although they are a probable source of the organic contaminants previously reported in this meteorite.

  13. Cosmic-ray-produced Cl-36 and Mn-53 in Allan Hills-77 meteorites

    NASA Astrophysics Data System (ADS)

    Nishiizumi, K.; Murrell, M. T.; Arnold, J. R.; Elmore, D.; Ferraro, R. D.; Gove, H. E.; Finkel, R. C.

    1981-01-01

    Cosmic-ray-produced Mn-53 has been determined by neutron activation in nine Allan Hills-77 meteorites. Additionally, Cl-36 has been measured in seven of these objects using tandem accelerator mass spectrometry. These results, along with C-14 and Al-26 concentrations determined elsewhere, yield terrestrial ages ranging from 10,000 to 700,000 years. Weathering was not found to result in Mn-53 loss.

  14. The discovery and initial characterization of Allan Hills 81005 - The first lunar meteorite

    NASA Technical Reports Server (NTRS)

    Marvin, U. B.

    1983-01-01

    Antarctic meteorite ALHA81005, discovered in the Allan Hills region of Victoria Land, is a polymict anorthositic breccia which differs from other meteorites in mineralogical and chemical composition but is strikingly similar to lunar highlands soil breccias. The petrologic character and several independent lines of evidence identify ALHA81005 as a meteorite from the moon. Two small clasts of probable mare basalt occur among the highlands lithologies in Thin Section 81005,22. This lunar specimen, which shows relatively minor shock effects, has generated new ideas on the types of planetary samples found on the earth.

  15. A unique type 3 ordinary chondrite containing graphite-magnetite aggregates - Allan Hills A77011

    NASA Technical Reports Server (NTRS)

    Mckinley, S. G.; Scott, E. R. D.; Taylor, G. J.; Keil, K.

    1982-01-01

    ALHA 77011, which is the object of study in the present investigation, is a chondrite of the 1977 meteorite collection from Allan Hills, Antarctica. It contains an opaque and recrystallized silicate matrix (Huss matrix) and numerous aggregates consisting of micron- and submicron-sized graphite and magnetite. It is pointed out that no abundant graphite-magnetite aggregates could be observed in other type 3 ordinary chondrites, except for Sharps. Attention is given to the results of a modal analysis, relations between ALHA 77011 and other type 3 ordinary chondrites, and the association of graphite-magnetite and metallic Fe, Ni. The discovery of graphite-magnetite aggregates in type 3 ordinary chondrites is found to suggest that this material may have been an important component in the formation of ordinary chondrites.

  16. Allan Hills 76005 Polymict Eucrite Pairing Group: Curatorial and Scientific Update on a Jointly Curated Meteorite

    NASA Technical Reports Server (NTRS)

    Righter, K.

    2011-01-01

    Allan Hills 76005 (or 765) was collected by the joint US-Japan field search for meteorites in 1976-77. It was described in detail as "pale gray in color and consists of finely divided macrocrystalline pyroxene-rich matrix that contains abundant clastic fragments: (1) Clasts of white, plagioclase-rich rocks. (2) Medium-gray, partly devitrified, cryptocrystalline. (3) Monomineralic fragments and grains of pyroxene, plagioclases, oxide minerals, sulfides, and metal. In overall appearance it is very similar to some lunar breccias." Subsequent studies found a great diversity of basaltic clast textures and compositions, and therefore it is best classified as a polymict eucrite. Samples from the 1976-77, 77-78, and 78-79 field seasons (76, 77, and 78 prefixes) were split between US and Japan (NIPR). The US specimens are currently at NASA-JSC, Smithsonian Institution, or the Field Museum in Chicago. After this initial finding of ALH 76005, the next year s team recovered one additional mass ALH 77302, and then four additional masses were found during the third season ALH 78040 and ALH 78132, 78158 and 78165. The joint US-Japan collection effort ended after three years and the US began collecting in the Trans-Antarctic Mountains with the 1979-80 and subsequent field seasons. ALH 79017 and ALH 80102 were recovered in these first two years, and then in 1981-82 field season, 6 additional masses were recovered from the Allan Hills. Of course it took some time to establish pairing of all of these specimens, but altogether the samples comprise 4292.4 g of material. Here will be summarized the scientific findings as well as some curatorial details of how specimens have been subdivided and allocated for study. A detailed summary is also presented on the NASA-JSC curation webpage for the HED meteorite compendium.

  17. Mawson Formation at Allan Hills, Antarctica: Evidence for a Large-scale Phreatomagmatic Caldera

    NASA Astrophysics Data System (ADS)

    Elliot, D. H.; Fortner, E. H.; Elliot, R. J.

    2003-12-01

    At Allan Hills, Transantarctic Mountains, Jurassic Mawson Formation pyroclastic rocks are more than 300 m thick. Previously described as unconformable on older Permian and Triassic Beacon strata, the Mawson is now known to be, at least in part, intrusive. Triassic Feather Formation country rocks at the contact display a zone of in situ brecciation. This is followed inward by a zone of megaclasts (10s of m long) derived from younger Triassic Lashly Formation strata, and then by a structureless, grey, sand-rich breccia which has increasing proportions of pyroclasts laterally and vertically. The grey breccia is overlain by units, up to 10s of m thick, of stratified tuff breccia and lapilli tuff, both of which consist of high proportions of Beacon and dolerite clasts set in a matrix of pyroclasts and sand-sized debris also derived from Beacon rocks. All but the brecciated country rocks are cut by basaltic diatremes, and by tuff-breccia and lapilli-tuff intrusive bodies. Megaclasts are mainly Lashly C strata which were a minimum of 120 m stratigraphically and topographically above any extant country rock, and demonstrate that the Mawson rocks are filling a collapse structure. The sequence of events is interpreted to be: 1) initial phreatic activity, on emplacement of a Ferrar Dolerite sill at depth, causing in situ brecciation; 2) withdrawal of magma and collapse of overlying strata to form a caldera containing megaclasts of Lashly strata; 3) renewed magma emplacement which initially caused phreatic activity but increasingly became phreatomagmatic, and formed the grey breccia by disaggregation of the collapsed Beacon strata; 4) full scale phreatomagmatism that erupted the stratified tuff breccia and lapilli tuff; 5) intrusion of basalt diatremes, bodies of tuff breccia and lapilli tuff, and dolerite plugs and dikes. Away from the mapped area, on the southern arm of Allan Hills, tuff breccia and lapilli tuff are crudely stratified and could be either outflow facies or

  18. Extreme metamorphism in a firn core from the Allan Hills, Antarctica, as an analogue for glacial conditions

    NASA Astrophysics Data System (ADS)

    Dadic, Ruzica; Schneebeli, Martin; Bertler, Nancy; Schwikowski, Margit; Matzl, Margret

    2015-04-01

    Understanding processes in near-zero accumulation areas can help to better understand the ranges of isotopic composition in ice cores, particularly during ice ages, when accumulation rates were lower than today. Snow metamorphism is a primary driver of the transition from snow to ice and can be accompanied by altered isotopic compositions and chemical species concentration. High degree snow metamorphism, which results in major structural changes, is little-studied but has been identified in certain places in Antarctica. Here we report on a 5-m firn core collected adjacent to a blue-ice field in the Allan Hills, Antarctica. We determined the physical properties of the snow using computer tomography (microCT) and measured the isotopic composition of δD and δ18O, as well as 210Pb activity. The core shows a high degree of snow metamorphism and an exponential decrease in specific surface area (SSA), but no clear densification, with depth. The micro-CT measurements show a homogenous and stable structure throughout the entire core, with obvious erosion features in the near-surface, where high-resolution data is available. The observed firn structure is likely caused by a combination of unique depositional and post-depositional processes. The defining depositional process is the impact deposition under high winds and with a high initial density. The defining post-depositional processes are a) increased moisture transport due to forced ventilation and high winds and b) decades of temperature-gradient driven metamorphic growth in the near surface due to prolonged exposure to seasonal temperature cycling. Both post-processes are enhanced in low accumulation regions where snow stays close to surface for a long time. We observe an irregular signal in δD and δ18O that does not follow the stratigraphic sequence. The isotopic signal is likely caused by the same post-depositional processes that are responsible for the firn structure, and that are driven by local climate

  19. Carbonates in fractures of Martian meteorite Allan Hills 84001: petrologic evidence for impact origin

    NASA Technical Reports Server (NTRS)

    Scott, E. R.; Krot, A. N.; Yamaguchi, A.

    1998-01-01

    Carbonates in Martian meteorite Allan Hills 84001 occur as grains on pyroxene grain boundaries, in crushed zones, and as disks, veins, and irregularly shaped grains in healed pyroxene fractures. Some carbonate disks have tapered Mg-rich edges and are accompanied by smaller, thinner and relatively homogeneous, magnesite microdisks. Except for the microdisks, all types of carbonate grains show the same unique chemical zoning pattern on MgCO3-FeCO3-CaCO3 plots. This chemical characteristic and the close spatial association of diverse carbonate types show that all carbonates formed by a similar process. The heterogeneous distribution of carbonates in fractures, tapered shapes of some disks, and the localized occurrence of Mg-rich microdisks appear to be incompatible with growth from an externally derived CO2-rich fluid that changed in composition over time. These features suggest instead that the fractures were closed as carbonates grew from an internally derived fluid and that the microdisks formed from a residual Mg-rich fluid that was squeezed along fractures. Carbonate in pyroxene fractures is most abundant near grains of plagioclase glass that are located on pyroxene grain boundaries and commonly contain major or minor amounts of carbonate. We infer that carbonates in fractures formed from grain boundary carbonates associated with plagiociase that were melted by impact and dispersed into the surrounding fractured pyroxene. Carbonates in fractures, which include those studied by McKay et al. (1996), could not have formed at low temperatures and preserved mineralogical evidence for Martian organisms.

  20. Bulk and stable isotopic compositions of carbonate minerals in Martian meteorite Allan Hills 84001: no proof of high formation temperature.

    PubMed

    Treiman, A H; Romanek, C S

    1998-07-01

    Understanding the origin of carbonate minerals in the Martian meteorite Allan Hills (ALH) 84001 is crucial to evaluating the hypothesis that they contain traces of ancient Martian life. Using arguments based on chemical equilibria among carbonates and fluids, an origin at >650 degrees C (inimical to life) has been proposed. However, the bulk and stable isotopic compositions of the carbonate minerals are open to multiple interpretations and so lend no particular support to a high-temperature origin. Other methods (possibly less direct) will have to be used to determine the formation temperature of the carbonates in ALH84001. PMID:11543073

  1. Bulk and Stable Isotopic Compositions of Carbonate Minerals in Martian Meteorite Allan Hills 84001: No Proof of High Formation Temperature

    NASA Technical Reports Server (NTRS)

    Treiman, Allan H.; Romanek, Christopher S.

    1998-01-01

    Understanding the origin of carbonate minerals in the Martian meteorite Allan Hills (ALH) 84001 is crucial to evaluating the hypothesis that they contain traces of ancient Martian life. Using arguments based on chemical equilibria among carbonates and fluids, an origin at greater than 650 C (inimical to life) has been proposed. However, the bulk and stable isotopic compositions of the carbonate minerals are open to multiple interpretations and so lend no particular support to a high-temperature origin. Other methods (possibly less direct) will have to be used to determine the formation temperature of the carbonates in ALH 84001.

  2. Isotopic evidence for a terrestrial source of organic compounds found in martian meteorites Allan Hills 84001 and Elephant Moraine 79001.

    PubMed

    Jull, A J; Courtney, C; Jeffrey, D A; Beck, J W

    1998-01-16

    Stepped-heating experiments on martian meteorites Allan Hills 84001 (ALH84001) and Elephant Moraine 79001 (EETA79001) revealed low-temperature (200 to 430 degrees Celsius) fractions with a carbon isotopic composition delta13C between -22 and -33 per mil and a carbon-14 content that is 40 to 60 percent of that of modern terrestrial carbon, consistent with a terrestrial origin for most of the organic material. Intermediate-temperature (400 to 600 degrees Celsius) carbonate-rich fractions of ALH84001 have delta13C of +32 to +40 per mil with a low carbon-14 content, consistent with an extraterrestrial origin, whereas some of the carbonate fraction of EETA79001 is terrestrial. In addition, ALH84001 contains a small preterrestrial carbon component of unknown origin that combusts at intermediate temperatures. This component is likely a residual acid-insoluble carbonate or a more refractory organic phase. PMID:9430584

  3. Geological evolution of the Coombs Allan Hills area, Ferrar large igneous province, Antarctica: Debris avalanches, mafic pyroclastic density currents, phreatocauldrons

    NASA Astrophysics Data System (ADS)

    Ross, Pierre-Simon; White, James D. L.; McClintock, Murray

    2008-05-01

    The Jurassic Ferrar large igneous province of Antarctica comprises igneous intrusions, flood lavas, and mafic volcaniclastic deposits (now lithified). The latter rocks are particularly diverse and well-exposed in the Coombs-Allan Hills area of South Victoria Land, where they are assigned to the Mawson Formation. In this paper we use these rocks in conjunction with the pre-Ferrar sedimentary rocks (Beacon Supergroup) and the lavas themselves (Kirkpatrick Basalt) to reconstruct the geomorphological and geological evolution of the landscape. In the Early Jurassic, the surface of the region was an alluvial plain, with perhaps 1 km of mostly continental siliciclastic sediments underlying it. After the fall of silicic ash from an unknown but probably distal source, mafic magmatism of the Ferrar province began. The oldest record of this event at Allan Hills is a ≤ 180 m-thick debris-avalanche deposit (member m1 of the Mawson Formation) which contains globular domains of mafic igneous rock. These domains are inferred to represent dismembered Ferrar intrusions emplaced in the source area of the debris avalanche; shallow emplacement of Ferrar magmas caused a slope failure that mobilized the uppermost Beacon Supergroup, and the silicic ash deposits, into a pre-existing valley or basin. The period which followed ('Mawson time') was the main stage for explosive eruptions in the Ferrar province, and several cubic kilometres of both new magma and sedimentary rock were fragmented over many years. Phreatomagmatic explosions were the dominant fragmentation mechanism, with magma-water interaction taking place in both sedimentary aquifers and existing vents filled by volcaniclastic debris. At Coombs Hills, a vent complex or 'phreatocauldron' was formed by coalescence of diatreme-like structures; at Allan Hills, member m2 of the Mawson Formation consists mostly of thick, coarse-grained, poorly sorted layers inferred to represent the lithified deposits of pyroclastic density currents

  4. Fine-Grained Rims in the Allan Hills 81002 and Lewis Cliff 90500 CM2 Meteorites: Their Origin and Modification

    NASA Technical Reports Server (NTRS)

    Hua, X.; Wang, J.; Buseck, P. R.

    2002-01-01

    Antarctic CM meteorites Allan Hills (ALH) 8 1002 and Lewis Cliff (LEW) 90500 contain abundant fine-grained rims (FGRs) that surround a variety of coarse-grained objects. FGRs from both meteorites have similar compositions and petrographic features, independent of their enclosed objects. The FGRs are chemically homogeneous at the 10 m scale for major and minor elements and at the 25 m scale for trace elements. They display accretionary features and contain large amounts of volatiles, presumably water. They are depleted in Ca, Mn, and S but enriched in P. All FGRs show a slightly fractionated rare earth element (REE) pattern, with enrichments of Gd and Yb and depletion of Er. Gd is twice as abundant as Er. Our results indicate that those FGRs are not genetically related to their enclosed cores. They were sampled from a reservoir of homogeneously mixed dust, prior to accretion to their parent body. The rim materials subsequently experienced aqueous alteration under identical conditions. Based on their mineral, textural, and especially chemical similarities, we conclude that ALH 8 1002 and LEW 90500 likely have a similar or identical source.

  5. Olivine in Martian Meteorite Allan Hills 84001: Evidence for a High-Temperature Origin and Implications for Signs of Life

    NASA Technical Reports Server (NTRS)

    Shearer, C. K.; Leshin, L. A.; Adcock, C. T.

    1999-01-01

    Olivine from Martian meteorite Allan Hills (ALH) 84001 occurs as clusters within orthopyroxene adjacent to fractures containing disrupted carbonate globules and feldspathic shock glass. The inclusions are irregular in shape and range in size from approx. 40 microns to submicrometer. Some of the inclusions are elongate and boudinage-like. The olivine grains are in sharp contact with the enclosing orthopyroxene and often contain small inclusions of chromite The olivine exhibits a very limited range of composition from Fo(sub 65) to Fo(sub 66) (n = 25). The delta(sup 18)O values of the olivine and orthopyroxene analyzed by ion microprobe range from +4.3 to +5.3% and are indistinguishable from each other within analytical uncertainty. The mineral chemistries, O-isotopic data, and textural relationships indicate that the olivine inclusions were produced at a temperature greater than 800 C. It is unlikely that the olivines formed during the same event that gave rise to the carbonates in ALH 84001, which have more elevated and variable delta(sup 18)O values, and were probably formed from fluids that were not in isotopic equilibrium with the orthopyroxene or olivine The reactions most likely instrumental in the formation of olivine could be either the dehydration of hydrous silicates that formed during carbonate precipitation or the reduction of orthopyroxene and spinel If the olivine was formed by either reaction during a postcarbonate beating event, the implications are profound with regards to the interpretations of McKay et al. Due to the low diffusion rates in carbonates, this rapid, high-temperature event would have resulted in the preservation of the fine-scale carbonate zoning' while partially devolatilizing select carbonate compositions on a submicrometer scale. This may have resulted in the formation of the minute magnetite grains that McKay et al attributed to biogenic activity.

  6. A nitrogen and argon stable isotope study of Allan Hills 84001: implications for the evolution of the Martian atmosphere.

    PubMed

    Grady, M M; Wright, I P; Pillinger, C T

    1998-07-01

    The abundances and isotopic compositions of N and Ar have been measured by stepped combustion of the Allan Hills 84001 (ALH 84001) Martian orthopyroxenite. Material described as shocked is N-poor ([N] approximately 0.34 ppm; delta 15N approximately +23%); although during stepped combustion, 15N-enriched N (delta 15N approximately +143%) is released in a narrow temperature interval between 700 degrees C and 800 degrees C (along with 13C-enriched C (delta 13C approximately +19%) and 40Ar). Cosmogenic species are found to be negligible at this temperature; thus, the isotopically heavy component is identified, in part, as Martian atmospheric gas trapped relatively recently in the history of ALH84001. The N and Ar data show that ALH84001 contains species from the Martian lithosphere, a component interpreted as ancient trapped atmosphere (in addition to the modern atmospheric species), and excess 40Ar from K decay. Deconvolution of radiogenic 40Ar from other Ar components, on the basis of end-member 36Ar/14N and 40Ar/36Ar ratios, has enabled calculation of a K-Ar age for ALH 84001 as 3.5-4.6 Ga, depending on assumed K abundance. If the component believed to be Martian palaeoatmosphere was introduced to ALH 84001 at the time the K-Ar age was set, then the composition of the atmosphere at this time is constrained to: delta 15N > or = +200%, 40Ar/36Ar < or = 3000 and 36Ar/14N > or = 17 x 10(-5). In terms of the petrogenetic history of the meteorite, ALH 84001 crystallised soon after differentiation of the planet, may have been shocked and thermally metamorphosed in an early period of bombardment, and then subjected to a second event. This later process did not reset the K-Ar system but perhaps was responsible for introducing (recent) atmospheric gases into ALH 84001; and it might mark the time at which ALH 84001 suffered fluid alteration resulting in the formation of the plagioclase and carbonate mineral assemblages. PMID:11543078

  7. Thermoluminescence survey of 12 meteorites collected by the European 1988 Antarctic meteorite expedition to Allan Hills and the importance of acid washing for thermoluminescence sensitivity measurements

    SciTech Connect

    Benoit, P.H.; Sears, H.; Sears, D.W.G. )

    1991-06-01

    Natural and induced thermoluminescence (TL) data are reported for 12 meteorites recovered from the Allan Hills region of Antarctica by the European field party during the 1988/1989 field season. The samples include one with extremely high natural TL, ALH88035, suggestive of exposure to unusually high radiation doses (i.e., low degrees of shielding), and one, ALH88034, whose low natural TL suggests reheating within the last 100,000 years. The remainder have natural TL values suggestive of terrestrial ages similar to those of other meteorites from Allan Hills. ALH88015 (L6) has induced TL data suggestive of intense shock. TL sensitivities of these meteorites are generally lower than observed falls of their petrologic types, as is also observed for Antarctic meteorites in general. Acid-washing experiments indicate that this is solely the result of terrestrial weathering rather than a nonterrestrial Antarctic-non-Antarctic difference. However, other TL parameters, such as natural TL and induced peak temperature-width, are unchanged by acid washing and are sensitive indicators of a meteorite's metamorphic and recent radiation history. 16 refs.

  8. Thermoluminescence survey of 12 meteorites collected by the European 1988 Antarctic meteorite expedition to Allan Hills and the importance of acid washing for thermoluminescence sensitivity measurements

    NASA Technical Reports Server (NTRS)

    Benoit, P. H.; Sears, H.; Sears, D. W. G.

    1991-01-01

    Natural and induced thermoluminescence (TL) data are reported for 12 meteorites recovered from the Allan Hills region of Antarctica by the European field party during the 1988/1989 field season. The samples include one with extremely high natural TL, ALH88035, suggestive of exposure to unusually high radiation doses (i.e., low degrees of shielding), and one, ALH88034, whose low natural TL suggests reheating within the last 100,000 years. The remainder have natural TL values suggestive of terrestrial ages similar to those of other meteorites from Allan Hills. ALH88015 (L6) has induced TL data suggestive of intense shock. TL sensitivities of these meteorites are generally lower than observed falls of their petrologic types, as is also observed for Antarctic meteorites in general. Acid-washing experiments indicate that this is solely the result of terrestrial weathering rather than a nonterrestrial Antarctic-non-Antarctic difference. However, other TL parameters, such as natural TL and induced peak temperature-width, are unchanged by acid washing and are sensitive indicators of a meteorite's metamorphic and recent radiation history.

  9. Thermoluminescence survey of 12 meteorites collected by the European 1988 Antarctic meteorite expedition to Allan Hills and the importance of acid washing for thermoluminescence sensitivity measurements

    NASA Astrophysics Data System (ADS)

    Benoit, P. H.; Sears, H.; Sears, D. W. G.

    1991-06-01

    Natural and induced thermoluminescence (TL) data are reported for 12 meteorites recovered from the Allan Hills region of Antarctica by the European field party during the 1988/1989 field season. The samples include one with extremely high natural TL, ALH88035, suggestive of exposure to unusually high radiation doses (i.e., low degrees of shielding), and one, ALH88034, whose low natural TL suggests reheating within the last 100,000 years. The remainder have natural TL values suggestive of terrestrial ages similar to those of other meteorites from Allan Hills. ALH88015 (L6) has induced TL data suggestive of intense shock. TL sensitivities of these meteorites are generally lower than observed falls of their petrologic types, as is also observed for Antarctic meteorites in general. Acid-washing experiments indicate that this is solely the result of terrestrial weathering rather than a nonterrestrial Antarctic-non-Antarctic difference. However, other TL parameters, such as natural TL and induced peak temperature-width, are unchanged by acid washing and are sensitive indicators of a meteorite's metamorphic and recent radiation history.

  10. Carbonates in the Martian meteorite Allan Hills 84001 formed at 18 ± 4 °C in a near-surface aqueous environment

    PubMed Central

    Halevy, Itay; Fischer, Woodward W.; Eiler, John M.

    2011-01-01

    Despite evidence for liquid water at the surface of Mars during the Noachian epoch, the temperature of early aqueous environments has been impossible to establish, raising questions of whether the surface of Mars was ever warmer than today. We address this problem by determining the precipitation temperature of secondary carbonate minerals preserved in the oldest known sample of Mars’ crust—the approximately 4.1 billion-year-old meteorite Allan Hills 84001 (ALH84001). The formation environment of these carbonates, which are constrained to be slightly younger than the crystallization age of the rock (i.e., 3.9 to 4.0 billion years), has been poorly understood, hindering insight into the hydrologic and carbon cycles of earliest Mars. Using “clumped” isotope thermometry we find that the carbonates in ALH84001 precipitated at a temperature of approximately 18 °C, with water and carbon dioxide derived from the ancient Martian atmosphere. Furthermore, covarying carbonate carbon and oxygen isotope ratios are constrained to have formed at constant, low temperatures, pointing to deposition from a gradually evaporating, subsurface water body—likely a shallow aquifer (meters to tens of meters below the surface). Despite the mild temperatures, the apparently ephemeral nature of water in this environment leaves open the question of its habitability. PMID:21969543

  11. Carbonates in the Martian meteorite Allan Hills 84001 formed at 18 +/- 4 degrees C in a near-surface aqueous environment.

    PubMed

    Halevy, Itay; Fischer, Woodward W; Eiler, John M

    2011-10-11

    Despite evidence for liquid water at the surface of Mars during the Noachian epoch, the temperature of early aqueous environments has been impossible to establish, raising questions of whether the surface of Mars was ever warmer than today. We address this problem by determining the precipitation temperature of secondary carbonate minerals preserved in the oldest known sample of Mars' crust--the approximately 4.1 billion-year-old meteorite Allan Hills 84001 (ALH84001). The formation environment of these carbonates, which are constrained to be slightly younger than the crystallization age of the rock (i.e., 3.9 to 4.0 billion years), has been poorly understood, hindering insight into the hydrologic and carbon cycles of earliest Mars. Using "clumped" isotope thermometry we find that the carbonates in ALH84001 precipitated at a temperature of approximately 18 °C, with water and carbon dioxide derived from the ancient Martian atmosphere. Furthermore, covarying carbonate carbon and oxygen isotope ratios are constrained to have formed at constant, low temperatures, pointing to deposition from a gradually evaporating, subsurface water body--likely a shallow aquifer (meters to tens of meters below the surface). Despite the mild temperatures, the apparently ephemeral nature of water in this environment leaves open the question of its habitability. PMID:21969543

  12. An abiotic origin for hydrocarbons in the Allan Hills 84001 martian meteorite through cooling of magmatic and impact-generated gases

    NASA Technical Reports Server (NTRS)

    Shock, E. L.

    2000-01-01

    Thermodynamic calculations of metastable equilibria were used to evaluate the potential for abiotic synthesis of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in the martian meteorite Allan Hills (ALH) 84001. The calculations show that PAHs and normal alkanes could form metastably from CO, CO2, and H2 below approximately 250-300 degrees C during rapid cooling of trapped magmatic or impact-generated gases. Depending on temperature, bulk composition, and oxidation-reduction conditions, PAHs and normal alkanes can form simultaneously or separately. Moreover, PAHs can form at lower H/C ratios, higher CO/CO2 ratios, and higher temperatures than normal alkanes. Dry conditions with H/C ratios less than approximately 0.01-0.001 together with high CO/CO2 ratios also favor the formation of unalkylated PAHs. The observed abundance of PAHs, their low alkylation, and a variable but high aromatic to aliphatic ratio in ALH 84001 all correspond to low H/C and high CO/CO2 ratios in magmatic and impact gases and can be used to deduce spatial variations of these ratios. Some hydrocarbons could have been formed from trapped magmatic gases, especially if the cooling was fast enough to prevent reequilibration. We propose that subsequent impact heating(s) in ALH 84001 could have led to dissociation of ferrous carbonates to yield fine-grain magnetite, formation of a CO-rich local gas phase, reduction of water vapor to H2, reequilibration of the trapped magmatic gases, aromatization of hydrocarbons formed previously, and overprinting of the synthesis from magmatic gases, if any. Rapid cooling and high-temperature quenching of CO-, H2-rich impact gases could have led to magnetite-catalyzed hydrocarbon synthesis.

  13. A comparison of the iddingsite alteration products in two terrestrial basalts and the Allan Hills 77005 martian meteorite using Raman spectroscopy and electron microprobe analyses

    NASA Astrophysics Data System (ADS)

    Kuebler, Karla E.

    2013-04-01

    We document the secondary mineral assemblages in two occurrences of terrestrial iddingsite, Lunar Crater, Nevada (LC) and Mauna Kea, Hawaii (MK), and compare these with the iddingsite in Allan Hills (ALHA) 77005. Short Raman spectroscopic traverses across olivine alteration fronts provide information about changes in mineralogy with alteration. Data from the Raman traverses are combined with electron microprobe (EMP) traverses at the same locations which provide information regarding element mobility and confirm mineral identifications made by Raman spectroscopy. This information is used with petrographic observations to argue for the martian origin of the iddingsite and jarosite, infer the sequence of alteration, and deliberate on the conditions and settings of alteration. Raman spectra indicate the presence of different iron oxides/oxyhydroxides in each sample (goethite in LC, maghemite in MK, and akaganéite in ALHA), and the terrestrial samples show different element mobility trends (loss of MgO and SiO2, retention of FeO) than ALHA (loss of MgO and FeO, influx of SiO2), whose trends reflect the deposition of jarosite. Altered olivine occur throughout the LC samples but only in the exteriors of the MK samples. The LC and MK alteration products formed by surface alteration, but ALHA 77005 is a lherzolite, and the olivine hosting the iddingsite are enclosed by orthopyroxene (appear to be restricted to the light lithology), suggesting that it formed at depth during magma consolidation. The ALHA iddingsite is an example of "deuteric alteration" (reaction with fluids that separated from the magma as crystallization progressed towards completion).

  14. An abiotic origin for hydrocarbons in the Allan Hills 84001 martian meteorite through cooling of magmatic and impact-generated gases.

    PubMed

    Zolotov MYu; Shock, E L

    2000-05-01

    Thermodynamic calculations of metastable equilibria were used to evaluate the potential for abiotic synthesis of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in the martian meteorite Allan Hills (ALH) 84001. The calculations show that PAHs and normal alkanes could form metastably from CO, CO2, and H2 below approximately 250-300 degrees C during rapid cooling of trapped magmatic or impact-generated gases. Depending on temperature, bulk composition, and oxidation-reduction conditions, PAHs and normal alkanes can form simultaneously or separately. Moreover, PAHs can form at lower H/C ratios, higher CO/CO2 ratios, and higher temperatures than normal alkanes. Dry conditions with H/C ratios less than approximately 0.01-0.001 together with high CO/CO2 ratios also favor the formation of unalkylated PAHs. The observed abundance of PAHs, their low alkylation, and a variable but high aromatic to aliphatic ratio in ALH 84001 all correspond to low H/C and high CO/CO2 ratios in magmatic and impact gases and can be used to deduce spatial variations of these ratios. Some hydrocarbons could have been formed from trapped magmatic gases, especially if the cooling was fast enough to prevent reequilibration. We propose that subsequent impact heating(s) in ALH 84001 could have led to dissociation of ferrous carbonates to yield fine-grain magnetite, formation of a CO-rich local gas phase, reduction of water vapor to H2, reequilibration of the trapped magmatic gases, aromatization of hydrocarbons formed previously, and overprinting of the synthesis from magmatic gases, if any. Rapid cooling and high-temperature quenching of CO-, H2-rich impact gases could have led to magnetite-catalyzed hydrocarbon synthesis. PMID:11543519

  15. Negative δ 18O values in Allan Hills 84001 carbonate: Possible evidence for water precipitation on mars

    NASA Astrophysics Data System (ADS)

    Holland, G.; Saxton, J. M.; Lyon, I. C.; Turner, G.

    2005-03-01

    The Martian meteorite ALH84001 contains ˜1% by weight of carbonate formed by secondary processes on the Martian surface or in the shallow subsurface. The major form of this carbonate is chemically and isotopically zoned rosettes which have been well documented elsewhere. This study concentrates upon carbonate regions ˜200 μm across which possess previously unobserved magnesium rich inner cores, interpreted here as rosette fragments, surrounded by a later stage cement containing rare Ca-rich carbonates (up to Ca 81Mg 07Fe 04Mn 07) intimately associated with feldspar. High spatial resolution ion probe analyses of Ca-rich carbonate surrounding rosette fragments have δ 18O V-SMOW values as low as -10 ‰. These values are not compatible with deposition from a global Martian atmosphere invoked to explain ALH84001 rosettes. The range of δ 18O values are also incompatible with a fluid that has equilibrated with the Martian crust at high temperature or from remobilisation of carbonate of rosette isotopic composition. At Martian atmospheric temperatures, the small CO 2(gas)-CO 2(ice) fractionation makes meteoric CO 2 an unlikely source for -10 ‰ carbonates. In contrast, closed system Rayleigh fractionation of H 2O can generate δ 18O H2O -30 ‰, as observed at high latitudes on Earth. We suggest that atmospheric transport and precipitation of H 2O in a similar fashion to that on Earth provides a source of suitably 18O depleted water for generation of carbonate with δ 18O V-SMOW = -10 ‰.

  16. Hydrograph peaks caused by ice channel melt in Black Hills streams

    SciTech Connect

    Rahn, P.H. . Dept. of Geology and Geological Engineering)

    1992-01-01

    The Black Hills has an average annual precipitation of approximately 20 inches, most of which occurs in early summer. The winters are typically cold and fairly dry. Most streams within the Precambrian central Black Hills have perennial and ephemeral reaches which are related to the presence of surficial deposits. During the winter, ice accumulates in the channels of some stream reaches, completely filling the channels, particularly in shady locations below springs or seeps. High discharges occur during warm spells in late winter and early spring. These high discharges are not due to snow melt because many watersheds are often void of snow. Ice-channel surveys were conducted on Spring, Battle, French, Slate, and Grace Coolidge Creeks during 1988. High discharges occurred during the warm spells at the end of March. Since no precipitation occurred during this time, and the watersheds were barren of snow, the discharge peaks are believed due to melting of ice stored in the channels. This hypothesis is supported by the fact that the volume of the water stored as ice was approximately the same as the volume of water represented by the discharge anomaly. The ice stored in channels primarily results from ground water discharge over the winter. It is not due to melting snow or surface water runoff per se. Separation of the hydrograph into surface and ground water components should take into account this phenomena.

  17. Assessing the continuity of the blue ice climate record at Patriot Hills, Horseshoe Valley, West Antarctica

    NASA Astrophysics Data System (ADS)

    Winter, Kate; Woodward, John; Dunning, Stuart A.; Turney, Chris S. M.; Fogwill, Christopher J.; Hein, Andrew S.; Golledge, Nicholas R.; Bingham, Robert G.; Marrero, Shasta M.; Sugden, David E.; Ross, Neil

    2016-03-01

    We use high-resolution ground-penetrating radar (GPR) to assess the continuity of the Blue Ice Area (BIA) horizontal climate record at Patriot Hills, Horseshoe Valley, West Antarctica. The sequence contains three pronounced changes in deuterium isotopic values at ~18 cal ka, ~12 cal ka, and ~8 cal ka. GPR surveys along the climate sequence reveal continuous, conformable dipping isochrones, separated by two unconformities in the isochrone layers, which correlate with the two older deuterium shifts. We interpret these unconformities as discontinuities in the sequence, rather than direct measures of climate change. Ice sheet models and Internal Layer Continuity Index plots suggest that the unconformities represent periods of erosion occurring, as the former ice surface was scoured by katabatic winds in front of mountains at the head of Horseshoe Valley. This study demonstrates the importance of high-resolution GPR surveys for investigating both paleoflow dynamics and interpreting BIA climate records.

  18. The Natural Thermoluminescence Survey of Antarctic Meteorites: Ordinary Chondrites at the Grosvenor Mountains, MacAlpine Hills, Pecora Escarpment and Queen Alexandra Range, and New Data New Data for the Elephant Moraine, Ice Fields

    NASA Technical Reports Server (NTRS)

    Benoit, Paul H.; Sears, Derek W. G.

    2000-01-01

    The natural TL survey of Antarctic meteorites was started in 1987 at the request of the Antarctic Meteorite Working Group in order to provide an initial description of radiation and thermal histories. It was intended to be a complement to the mineralogical and petrographic surveys performed at the Johnson Space Center and the Smithsonian Institution. All ANSMET samples recovered since then, besides those that were heated throughout by atmospheric passage, have been measured. To date this amounts to about 1200 samples. As the data for each ice field reaches a significant level, we have been conducting a thorough examination of the data for that field with a view to (1) identifying pairing, (2) providing an estimate of terrestrial age and residence time on the ice surface, (3) looking for differences in natural TL between ice fields, (4) looking for variations in natural TL level with location on the ice, (5) looking for meteorites with natural TL levels outside the normal range. Pairing is a necessary first step in ensuring the @ost productive use of the collection, while geographical variations could perhaps provide clues to concentration mechanisms. Samples with natural TL values outside the normal range are usually inferred to have had either small perihelia or recent changes in orbital elements. In addition, induced TL data have enabled us to (5) look for evidence for secular variation in the nature of the flux of meteorites to Earth, and (6) look for petrologically unusual meteorites, such as particularly primitive ordinary chondrites, heavily shocked meteorites, or otherwise anomalous meteorites. To date we have published studies of the TL properties of 167 ordinary chondrites from Allan Hills, 107 from Elephant Moraine and 302 from Lewis Cliff and we have discussed the TL properties of fifteen H chondrites collected at the Allan Hills by Euromet after a storm during the 1988 season. We now have additional databases for a reasonable number of ordinary

  19. The Natural Thermoluminescence Survey of Antarctic Meteorites: Ordinary Chondrites at the Grosvenor Mountains, Macalpine Hills, Pecora Escarpment and Queen Alexandra Range, and New Data for the Elephant Moraine, Ice Fields

    NASA Technical Reports Server (NTRS)

    Benoit, Paul H.; Sears, Derek W. G.

    1999-01-01

    The natural TL (Thermoluminescence) survey of Antarctic meteorites was started in 1987 at the request of the Antarctic Meteorite Working Group in order to provide an initial description of radiation and thermal histories. It was intended to be a complement to the mineralogical and petrographic surveys performed at the Johnson Space Center and the Smithsonian Institution. All ANSMET (Antarctic Search for Meteorites) samples recovered since then, besides those that were heated throughout by atmospheric passage, have been measured. To date this amounts to about 1200 samples. As the data for each ice field reaches a significant level, we have been conducting a thorough examination of the data for that field with a view to identifying pairing, providing an estimate of terrestrial age and residence time on the ice surface, looking for differences in natural TL between ice fields, looking for variations in natural TL level with location on the ice, looking for meteorites with natural TL levels outside the normal range. Pairing is a necessary first step in ensuring the most productive use of the collection, while geographical variations could perhaps provide clues to concentration mechanisms. Samples with natural TL values outside the normal range are usually inferred to have had either small perihelia or recent changes in orbital elements. In addition, induced TL data have enabled us to look for evidence for secular variation in the nature of the flux of meteorites to Earth, and look for petrologically unusual meteorites, such as particularly primitive ordinary chondrites, heavily shocked meteorites, or otherwise anomalous meteorites. To date we have published studies of the TL properties of 167 ordinary chondrites from Allan Hills, 107 from Elephant Moraine and 302 from Lewis Cliff and we have discussed the TL properties of fifteen H chondrites collected at the Allan Hills by Euromet after a storm during the 1988 season. We now have additional databases for a reasonable

  20. Meteorites and Microbes: Meteorite Collection and Ice Sampling at Patriot Hills, Thiel Mountains, and South Pole, Antarctica

    NASA Technical Reports Server (NTRS)

    Sipiera, Paul P.; Hoover, Richard B.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    During the Antarctica 2000 Expedition, sponsored by the Planetary Studies Foundation, meteorites and ice microbiota were collected from the Patriot Hills, and Thiel Mountains of Antarctica and snow samples were at the South Pole. Psychrophilic and psychrotrophic microbiota were obtained from blue ice, cryoconite and ice-bubble systems. Twenty frozen meteorites were collected using aseptic techniques from the blue ice fields near the Moulton Escarpment of the Thiel Mountains (85 S, 94 W) and from the Morris Moraine of the Patriot Hills (80 S, 81 W) Ellsworth Mountains. These ice and meteorite samples are of potential significance to Astrobiology. They may help refine chemical and morphological biomarkers and refine characteristics of microbial life in one of the harshest environments on Earth. We discuss the Antarctica 2000 Expedition and provide preliminary results of the investigation of the meteorites and ice microbiota recovered.

  1. Measurements of Cl-36 in Antarctic meteorites and Antarctic ice using a Van de Graaff accelerator

    NASA Technical Reports Server (NTRS)

    Nishiizumi, K.; Arnold, J. R.; Finkel, R. C.; Elmore, D.; Ferraro, R. D.; Gove, H. E.; Beukens, R. P.; Chang, K. H.; Kilius, L. R.

    1979-01-01

    The paper presents measurements of cosmic-ray produced (Cl-36) in Antarctic meteorites and ice using a Van de Graaff accelerator as an ultrasensitive mass spectrometer. Results from this ion counting technique are used to support a two-stage irradiation model for the Yamato-7301 and Allan Hills-76008 meteorites and to show a long terrestrial age for Allan Hills-77002. Yamato-7304 has a terrestrial age of less than 0.1 m.y., and the (Cl-36) content of the Antarctic ice sample from the Yamato mountain is consistent with levels expected in currently depositing snow implying that the age of the ice cap at this site is less than on (Cl-36) half-life.

  2. Sedimentology and geochemistry of a perennially ice-covered epishelf lake in Bunger Hills Oasis, East Antarctica

    NASA Technical Reports Server (NTRS)

    Doran, P. T.; Wharton, R. A. Jr; Lyons, W. B.; Des Marais, D. J.; Andersen, D. T.; Wharton RA, J. r. (Principal Investigator)

    2000-01-01

    A process-oriented study was carried out in White Smoke lake, Bunger Hills, East Antarctica, a perennially ice-covered (1.8 to 2.8 m thick) epishelf (tidally-forced) lake. The lake water has a low conductivity and is relatively well mixed. Sediments are transferred from the adjacent glacier to the lake when glacier ice surrounding the sediment is sublimated at the surface and replaced by accumulating ice from below. The lake bottom at the west end of the lake is mostly rocky with a scant sediment cover. The east end contains a thick sediment profile. Grain size and delta 13C increase with sediment depth, indicating a more proximal glacier in the past. Sedimentary 210Pb and 137Cs signals are exceptionally strong, probably a result of the focusing effect of the large glacial catchment area. The post-bomb and pre-bomb radiocarbon reservoirs are c. 725 14C yr and c. 1950 14C yr, respectively. Radiocarbon dating indicates that the east end of the lake is >3 ka BP, while photographic evidence and the absence of sediment cover indicate that the west end has formed only over the last century. Our results indicate that the southern ice edge of Bunger Hills has been relatively stable with only minor fluctuations (on the scale of hundreds of metres) over the last 3000 years.

  3. Meteorites and the Antarctic ice sheet

    NASA Technical Reports Server (NTRS)

    Cassidy, W. A.

    1986-01-01

    The majority of the meteorite finds were located in the Allan Hills site. All the expected goals involving the recovery of rare or previously unknown types of meteorites, and even the recovery of lunar ejecta, were realized. The relationship between these remarkable concentrations of meteorites and the Antarctic ice sheet itself were less well documented. Ice flow vector studies were made and concentration models were proposed. Earlier estimates of the abundances of meteorite types were based on the number of falls in the world collections. The accumulated data and the future collected data will allow more reliable estimates of the source region of most meteorites.

  4. Meteorite infall as a function of mass - Implications for the accumulation of meteorites on Antarctic ice

    NASA Technical Reports Server (NTRS)

    Huss, Gary R.

    1990-01-01

    Antarctic meteorites are considerably smaller, on average, than those recovered elsewhere in the world, and seem to represent a different portion of the mass distribution of infalling meteorites. When an infall rate appropriate to the size of Antarctic meteorites is used (1000 meteorites 10 grams or larger/sq km/1 million years), it is found that direct infall can produce the meteorite accumulations found on eight ice fields in the Allan Hills region in times ranging from a few thousand to nearly 200,000 years, with all but the Allan Hills Main and Near Western ice fields requiring less than 30,000 years. Meteorites incorporated into the ice over time are concentrated on the surface when the ice flows into a local area of rapid ablation. The calculated accumulation times, which can be considered the average age of the exposed ice, agree well with terrestrial ages for the meteorites and measured ages of exposed ice. Since vertical concentration of meteorites through removal of ice by ablation is sufficient to explain the observed meteorite accumulations, there is no need to invoke mechanisms to bring meteorites from large areas to the relatively small blue-ice patches where they are found. Once a meteorite is on a bare ice surface, freeze-thaw cycling and wind break down the meteorite and remove it from the ice. The weathering lifetime of a 100-gram meteorite on Antarctic ice is on the order of 10,000 + or - 5,000 years.

  5. Spectral Ambiguity of Allan Variance

    NASA Technical Reports Server (NTRS)

    Greenhall, C. A.

    1996-01-01

    We study the extent to which knowledge of Allan variance and other finite-difference variances determines the spectrum of a random process. The variance of first differences is known to determine the spectrum. We show that, in general, the Allan variance does not. A complete description of the ambiguity is given.

  6. Autonomy Software Architecture for LORAX (Life On ice Robotic Antarctic eXplorer)

    NASA Technical Reports Server (NTRS)

    Jonsson, Ari; McGann, Conor; Pedersen, Liam; Iatauro, Michael; Rajagopalan, Srikanth

    2005-01-01

    LORAX is a robotic astrobiological study of the ice field surrounding the Carapace Nunatak near the Allan Hills in Antarctica. The study culminates in a l00km traverse, sampling the ice at various depths (from surface to 10cm) at over 100 sites to survey microbial ecology and to record environmental parameters. The autonomy requirements from LORAX are shared by many robotic exploration tasks. Consequently, the LORAX autonomy architecture is a general architecture for on-board planning and execution in environments where science return is to be maximized against resource limitations and other constraints.

  7. Allan Cox 1926”1987

    NASA Astrophysics Data System (ADS)

    Coe, Rob; Dalrymple, Brent

    More than 1000 friends, students, and colleagues from all over the country filled Stanford Memorial Chapel (Stanford, Calif.) on February 3, 1987, to join in “A Celebration of the Life of Allan Cox.” Allan died early on the morning of January 27 while bicycling, the sport he had come to love the most. Between pieces of his favorite music by Bach and Mozart, Stanford administrators and colleagues spoke in tribute of Allan's unique qualities as friend, scientist, teacher, and dean of the School of Earth Sciences. James Rosse, Vice President and Provost of Stanford University, struck a particularly resonant chord with his personal remarks: "Allan reached out to each person he knew with the warmth and attention that can only come from deep respect and affection for others. I never heard him speak ill of others, and I do not believe he was capable of doing anything that would harm another being. He cared too much to intrude where he was not wanted, but his curiosity about people and the loving care with which he approached them broke down reserve to create remarkable friendships. His enthusiasm and good humor made him a welcome guest in the hearts of the hundreds of students and colleagues who shared the opportunity of knowing Allan Cox as a person."

  8. Meteoritic event recorded in Antarctic ice

    SciTech Connect

    Harvey, R.P.; Dunbar, N.W.; McIntosh, W.C.; Esser, R.P.; Nishiizumi, Kuni; Taylor, S.; Caffee, M.W.

    1998-07-01

    During systematic sampling of volcanic ash (tephra) layers at a well-known Antarctic meteorite collection site (the Allan Hills main ice field), a band of unusually dark and rounded (many spheroidal) particles was discovered. This debris layer (BIT-58) extends parallel to the stratigraphy of the ice established from the tephra bands, apparently marking a single depositional event. The shapes, internal texture, major element composition, and levels of cosmogenic nuclides of particles from within BIT-58 all strongly suggest that this material represents ablation debris from the passage of a large H-group ordinary chondrite. Preliminary cosmogenic isotope dating suggests an age of 2.8 Ma, implying that the East Antarctic ice sheet has been stable since that time. The relationship of the Bit-58 layer to known impact events is not clear.

  9. Edgar Allan Poe and neurology.

    PubMed

    Teive, Hélio Afonso Ghizoni; Paola, Luciano de; Munhoz, Renato Puppi

    2014-06-01

    Edgar Allan Poe was one of the most celebrated writers of all time. He published several masterpieces, some of which include references to neurological diseases. Poe suffered from recurrent depression, suggesting a bipolar disorder, as well as alcohol and drug abuse, which in fact led to his death from complications related to alcoholism. Various hypotheses were put forward, including Wernicke's encephalopathy. PMID:24964115

  10. Allan Bloom's Quarrel with History.

    ERIC Educational Resources Information Center

    Thompson, James

    1988-01-01

    Responds to Allan Bloom's "The Closing of the American Mind." Concludes that despite cranky comments about bourgeois culture, the focus of Bloom's attack is on historicism, which undercuts his nostalgic vision of a prosperous and just America. Condemns Bloom's exclusion of Blacks, Hispanics, and women from America's cultural heritage. (DMM)

  11. Estimating the Modified Allan Variance

    NASA Technical Reports Server (NTRS)

    Greenhall, Charles

    1995-01-01

    The third-difference approach to modified Allan variance (MVAR) leads to a tractable formula for a measure of MVAR estimator confidence, the equivalent degrees of freedom (edf), in the presence of power-law phase noise. The effect of estimation stride on edf is tabulated. A simple approximation for edf is given, and its errors are tabulated. A theorem allowing conservative estimates of edf in the presence of compound noise processes is given.

  12. From IDs to Ice Cream to "I, Claudius": Security Is in the Cards at Cleveland Hill Union Free School District.

    ERIC Educational Resources Information Center

    Passmore, Cheryl

    2002-01-01

    Describes the use of plastic identity badges with photographs and barcodes issued to all administrators, teachers, staff members, and students in grades 6-12 at the Cleveland Hill Union Free School District in Cheektowaga, New York. (PKP)

  13. A Wavelet Perspective on the Allan Variance.

    PubMed

    Percival, Donald B

    2016-04-01

    The origins of the Allan variance trace back 50 years ago to two seminal papers, one by Allan (1966) and the other by Barnes (1966). Since then, the Allan variance has played a leading role in the characterization of high-performance time and frequency standards. Wavelets first arose in the early 1980s in the geophysical literature, and the discrete wavelet transform (DWT) became prominent in the late 1980s in the signal processing literature. Flandrin (1992) briefly documented a connection between the Allan variance and a wavelet transform based upon the Haar wavelet. Percival and Guttorp (1994) noted that one popular estimator of the Allan variance-the maximal overlap estimator-can be interpreted in terms of a version of the DWT now widely referred to as the maximal overlap DWT (MODWT). In particular, when the MODWT is based on the Haar wavelet, the variance of the resulting wavelet coefficients-the wavelet variance-is identical to the Allan variance when the latter is multiplied by one-half. The theory behind the wavelet variance can thus deepen our understanding of the Allan variance. In this paper, we review basic wavelet variance theory with an emphasis on the Haar-based wavelet variance and its connection to the Allan variance. We then note that estimation theory for the wavelet variance offers a means of constructing asymptotically correct confidence intervals (CIs) for the Allan variance without reverting to the common practice of specifying a power-law noise type a priori. We also review recent work on specialized estimators of the wavelet variance that are of interest when some observations are missing (gappy data) or in the presence of contamination (rogue observations or outliers). It is a simple matter to adapt these estimators to become estimators of the Allan variance. Finally we note that wavelet variances based upon wavelets other than the Haar offer interesting generalizations of the Allan variance. PMID:26529757

  14. Estimating the Modified Allan Variance

    NASA Technical Reports Server (NTRS)

    Greenhall, Charles

    1995-01-01

    A paper at the 1992 FCS showed how to express the modified Allan variance (mvar) in terms of the third difference of the cumulative sum of time residuals. Although this reformulated definition was presented merely as a computational trick for simplifying the calculation of mvar estimates, it has since turned out to be a powerful theoretical tool for deriving the statistical quality of those estimates in terms of their equivalent degrees of freedom (edf), defined for an estimator V by edf V = 2(EV)2/(var V). Confidence intervals for mvar can then be constructed from levels of the appropriate 2 distribution.

  15. Mineral Biomarkers in Martian Meteorite Allan Hills 84001?

    NASA Technical Reports Server (NTRS)

    Thomas-Keprta, K. L.; Bazylinski, D. A.; Wentworth, S. J.; McKay, D. S.; Golden, D. C.; Gibson, E. K., Jr.; Romanek, C. S.

    1998-01-01

    The occurrence of fine-grained magnetite in the Fe-rich rims surrounding carbonate globules in the martian meteorite ALH84001, originally described in , have been proposed as fossil remains of primitive martian organisms. Here we report observations on size and shape distributions of magnetites from ALH84001 and compare them to biogenic and inorganic magnetite crystals of terrestrial origin. While some magnetite morphology is not unequivocally diagnostic for its biogenicity, such as cubodial forms of magnetite, which are common in inorganically formed magnetites, other morphologies of magnetite (parallel-epiped or elongated prismatic and arrowhead forms) are more likely signatures of biogenic activity. Some ALH 84001 magnetite particles described below have unique morphology and length-to-width ratios that are indistinguishable from a variety of terrestrial biogenic magnetite and distinct from all known inorganic forms of magnetite.

  16. Origin of Carbonate in Martian Meteorite Allan Hills 84001

    NASA Astrophysics Data System (ADS)

    Scott, E. R. D.; Krot, A. N.

    1998-01-01

    A significant argument advanced by McKay et al., in favor of a biogenic origin of the carbonates in ALH 84001 was that abiogenic origins - both low and high temperature - appeared to be less plausible. However, subsequent shock studies have suggested that impact heating may have modified carbonates. We inferred that plagioclase glass and rare silica grains formed from impact melts, and Raman spectroscopy confirmed that plagiociase had been melted at greater than 1200C, suggesting shock pressures exceeded 35-45 GPa. Morphological similarities between grains of plagioclase glass and irregularly shaped carbonates in fractures and the occurrence of intermixed grains in fractures suggested that carbonates may also have been shock heated so that a CO2-rich fluid was injected into cooler-fractured pyroxene during shock decompression causing crystallization in seconds.

  17. Rubidium-Strontium Formation Age of Allan Hills 84001 Carbonates

    NASA Technical Reports Server (NTRS)

    Borg, L. E.; Nyquist, L. E.; Shih, C.-Y.; Weismann, H.; Reese, Y.; Connelly, J. N.

    1998-01-01

    Our preferred age for the formation of carbonates in the martian meteorite ALH 84001 is 3.90 plus or minus 0.04 Ga for Lambda (Rubidium 87) equals 0.01402 Ga (exp -1), or 3.85 plus or minus 0.04 Ga for Lambda (Rubidium 87) = 0.0142 Ga(exponent -1). This age is determined by a three-point Rb-Sr isochron defined by leachates of high-graded carbonate-rich material. Major cation and especially phosphorous analyses of the leachates permit contributions from igneous whitlockite to be recognized for low-acidity leachates, and the corresponding data are omitted from the isochron. Data for the two highest acidity leachates plot close to the preferred isochron, but are omitted because we believe they contain contributions leached from the pyroxene substrate on which most of the carbonates are found. Nevertheless, the isochron age for all five highest-acidity leachates is 3.94 plus or minus 0.04 Ga, and is within error of the age obtained for the more restricted data set. All leachates used to define the isochron have major cation compositions that are singular to those obtained by microprobe analyses of the carbonate rosettes and are consistent with progressive digestion of the carbonates according to their composition. The age thus obtained for the carbonates is about 600 m.y. younger than the crystalization age of ALH 84001 determined by Sm-Nd analyses but is within error limits of the age of impact metamorphism inferred from the Rb-Sr and Ar-Ar systematics of silicates. which yield ages of 3.85 plus or minus 0.05 Ga and 4.05- 3.80 Ga to 4.3-3.8 Ga, respectively. Similarities between the carbonate crystallization age and the age of impact metamorphism as determined by Ar-Ar and Rb-Sr suggest that the carbonate formation is impact-related. Nevertheless, both high and low- temperature scenarios for the origin of the carbonates are possible.

  18. Significant melting of ice-wedges and formation of thermocirques on hill-slopes of thermokarst lakes in Central Yakutia (Siberia)

    NASA Astrophysics Data System (ADS)

    Séjourné, Antoine; Costard, François; Gargani, Julien; Fedorov, Alexander; Skorve, Johnny

    2013-04-01

    On Earth, permafrost containing a high ice volume (referred as ice-rich) are sensible to climate change, they have been regionally degraded (thermokarst) during the early Holocene climatic optimum forming numerous thermokarst lakes in Central Yakutia (eastern Siberia). Recent temperature increases in the Arctic and Subarctic have been significantly greater than global averages. The frequency and magnitude of terrain disturbances associated with thawing permafrost are increasing in these regions and are thought to intensify in the future. Therefore, understand how is the current development of thermokarst is a critical question. Here, we describe the significant melting of ice-wedges on slopes of thermokarst lakes that leads to formation of amphitheatrical hollows referred as thermocirques. The evolution of thermocirques in Central Yakutia has been little studied and analyzing their formation could help to understand the recent thermokarst in relation to climate change in Central Yakutia. We studied the thermocirques at two scales: (i) field surveys of different thermocirques in July 2009-2010 and October 2012 to examine the processes and origin of melting of ice-wedges and; (ii) photo-interpretation of time series of satellite images (KH-9 Hexagon images of 6-9 m/pixel and GeoEye images of 50 cm/pixel) to study the temporal evolution of thermocirques. The melting of ground-ice on the scarp of thermocirque triggers falls and small mud-flows that induce the retreat of the scarp parallel to itself. Based on field studies and on GeoEye image comparison, we show that their rate of retrogressive growth is 1-2 m/year. On the hill-slopes of lakes, the thermokarst could be initiated by different processes that lead to the uncover and then melting of ice-wedges: thermal erosion by the waves of the ice-rich bluff; active-layer detachment (a form of slope failure linked to detachment of the seasonally thawed upper ground); flowing of water on the slope (precipitation) or

  19. Edgar Allan Poe's Physical Cosmology

    NASA Astrophysics Data System (ADS)

    Cappi, Alberto

    1994-06-01

    In this paper I describe the scientific content of Eureka, the prose poem written by Edgar Allan Poe in 1848. In that work, starting from metaphysical assumptions, Poe claims that the Universe is finite in an infinite Space, and that it was originated from a primordial Particle, whose fragmentation under the action of a repulsive force caused a diffusion of atoms in space. I will show that his subsequently collapsing universe represents a scientifically acceptable Newtonian model. In the framework of his evolving universe, Poe makes use of contemporary astronomical knowledge, deriving modern concepts such as a primordial atomic state of the universe and a common epoch of galaxy formation. Harrison found in Eureka the first, qualitative solution of the Olbers' paradox; I show that Poe also applies in a modern way the anthropic principle, trying to explain why the Universe is so large.

  20. John A. Scigliano Interviews Allan B. Ellis.

    ERIC Educational Resources Information Center

    Scigliano, John A.

    2000-01-01

    This interview with Allan Ellis focuses on a history of computer applications in education. Highlights include work at the Harvard Graduate School of Education; the New England Education Data System; and efforts to create a computer-based distance learning and development program called ISVD (Information System for Vocational Decisions). (LRW)

  1. The Curious Mind of Allan Bloom.

    ERIC Educational Resources Information Center

    Gardner, Martin

    1988-01-01

    This article reviews Allan Bloom's 1987 book, THE CLOSING OF THE AMERICAN MIND: HOW HIGHER EDUCATION HAS FAILED DEMOCRACY AND IMPOVERISHED THE SOULS OF TODAY'S CHILDREN. Compares Bloom's book with THE HIGHER LEARNING IN AMERICA, a 1930s book by Mortimer Adler and Robert Hutchins. (JDH)

  2. Possible Meteorites in the Martian Hills

    NASA Technical Reports Server (NTRS)

    2006-01-01

    From its winter outpost at 'Low Ridge' inside Gusev Crater, NASA's Mars Exploration Rover Spirit took this spectacular, color mosaic of hilly, sandy terrain and two potential iron meteorites. The two light-colored, smooth rocks about two-thirds of the way up from the bottom of the frame have been labeled 'Zhong Shan' and 'Allan Hills.'

    The two rocks' informal names are in keeping with the rover science team's campaign to nickname rocks and soils in the area after locations in Antarctica. Zhong Shang is an Antarctic base that the People's Republic of China opened on Feb. 26, 1989, at the Larsemann Hills in Prydz Bay in East Antarctica. Allan Hills is a location where researchers have found many Martian meteorites, including the controversial ALH84001, which achieved fame in 1996 when NASA scientists suggested that it might contain evidence for fossilized extraterrestrial life. Zhong Shan was the given name of Dr. Sun Yat-sen (1866-1925), known as the 'Father of Modern China.' Born to a peasant family in Guangdong, Sun moved to live with his brother in Honolulu at age 13 and later became a medical doctor. He led a series of uprisings against the Qing dynasty that began in 1894 and eventually succeeded in 1911. Sun served as the first provisional president when the Republic of China was founded in 1912.

    The Zhong Shan and Allan Hills rocks, at the left and right, respectively, have unusual morphologies and miniature thermal emission spectrometer signatures that resemble those of a rock known as 'Heat Shield' at the Meridiani site explored by Spirit's twin, Opportunity. Opportunity's analyses revealed Heat Shield to be an iron meteorite.

    Spirit acquired this approximately true-color image on the rover's 872nd Martian day, or sol (June 16, 2006), using exposures taken through three of the panoramic camera's filters, centered on wavelengths of 600 nanometers, 530 nanometers, and 480 nanometers.

  3. Allan-Herndon syndrome. I. Clinical studies.

    PubMed Central

    Stevenson, R E; Goodman, H O; Schwartz, C E; Simensen, R J; McLean, W T; Herndon, C N

    1990-01-01

    A large family with X-linked mental retardation, originally reported in 1944 by Allan, Herndon, and Dudley, has been reinvestigated. Twenty-nine males have been affected in seven generations. Clinical features include severe mental retardation, dysarthria, ataxia, athetoid movements, muscle hypoplasia, and spastic paraplegia with hyperreflexia, clonus, and Babinski reflexes. The facies appear elongated with normal head circumference, bitemporal narrowing, and large, simple ears. Contractures develop at both small and large joint. Statural growth is normal and macroorchidism does not occur. Longevity is not impaired. High-resolution chromosomes, serum creatine kinase, and amino acids are normal. This condition, termed the Allan-Herndon syndrome, appears distinct from other X-linked disorders having mental retardation, muscle hypoplasia, and spastic paraplegia. Images Figure 2 Figure 3 PMID:2393019

  4. The Cosmology of Edgar Allan Poe

    NASA Astrophysics Data System (ADS)

    Cappi, Alberto

    2011-06-01

    Eureka is a ``prose poem'' published in 1848, where Edgar Allan Poe presents his original cosmology. While starting from metaphysical assumptions, Poe develops an evolving Newtonian model of the Universe which has many and non casual analogies with modern cosmology. Poe was well informed about astronomical and physical discoveries, and he was influenced by both contemporary science and ancient ideas. For these reasons, Eureka is a unique synthesis of metaphysics, art and science.

  5. [The medical history of Edgar Allan Poe].

    PubMed

    Miranda C, Marcelo

    2007-09-01

    Edgar Allan Poe, one of the best American storytellers and poets, suffered an episodic behaviour disorder partially triggered by alcohol and opiate use. Much confusion still exists about the last days of his turbulent life and the cause of his death at an early age. Different etiologies have been proposed to explain his main medical problem, however, complex partial seizures triggered by alcohol, poorly recognized at the time when Poe lived, seems to be one of the most acceptable hypothesis, among others discussed. PMID:18064380

  6. Friis Hills Drilling Project - Coring an Early to mid-Miocene terrestrial sequence in the Transantarctic Mountains to examine climate gradients and ice sheet variability along an inland-to-offshore transect

    NASA Astrophysics Data System (ADS)

    Lewis, A. R.; Levy, R. H.; Naish, T.; Gorman, A. R.; Golledge, N.; Dickinson, W. W.; Kraus, C.; Florindo, F.; Ashworth, A. C.; Pyne, A.; Kingan, T.

    2015-12-01

    The Early to mid-Miocene is a compelling interval to study Antarctic ice sheet (AIS) sensitivity. Circulation patterns in the southern hemisphere were broadly similar to present and reconstructed atmospheric CO2 concentrations were analogous to those projected for the next several decades. Geologic records from locations proximal to the AIS are required to examine ice sheet response to climate variability during this time. Coastal and offshore drill core records recovered by ANDRILL and IODP provide information regarding ice sheet variability along and beyond the coastal margin but they cannot constrain the extent of inland retreat. Additional environmental data from the continental interior is required to constrain the magnitude of ice sheet variability and inform numerical ice sheet models. The only well-dated terrestrial deposits that register early to mid-Miocene interior ice extent and climate are in the Friis Hills, 80 km inland. The deposits record multiple glacial-interglacial cycles and fossiliferous non-glacial beds show that interglacial climate was warm enough for a diverse biota. Drifts are preserved in a shallow valley with the oldest beds exposed along the edges where they terminate at sharp erosional margins. These margins reveal drifts in short stratigraphic sections but none is more than 13 m thick. A 34 m-thick composite stratigraphic sequence has been produced from exposed drift sequences but correlating beds in scattered exposures is problematic. Moreover, much of the sequence is buried and inaccessible in the basin center. New seismic data collected during 2014 reveal a sequence of sediments at least 50 m thick. This stratigraphic package likely preserves a detailed and more complete sedimentary sequence for the Friis Hills that can be used to refine and augment the outcrop-based composite stratigraphy. We aim to drill through this sequence using a helicopter-transportable diamond coring system. These new cores will allow us to obtain

  7. Obituary: Allan R. Sandage (1926-2010)

    NASA Astrophysics Data System (ADS)

    Devorkin, David

    2011-12-01

    Allan Rex Sandage died of pancreatic cancer at his home in San Gabriel, California, in the shadow of Mount Wilson, on November 13, 2010. Born in Iowa City, Iowa, on June 18, 1926, he was 84 years old at his death, leaving his wife, former astronomer Mary Connelly Sandage, and two sons, David and John. He also left a legacy to the world of astronomical knowledge that has long been universally admired and appreciated, making his name synonymous with late 20th-Century observational cosmology. The only child of Charles Harold Sandage, a professor of advertising who helped establish that academic specialty after obtaining a PhD in business administration, and Dorothy Briggs Sandage, whose father was president of Graceland College in Iowa, Allan Sandage grew up in a thoroughly intellectual, university oriented atmosphere but also a peripatetic one taking him to Philadelphia and later to Illinois as his father rose in his career. During his 2 years in Philadelphia, at about age eleven, Allan developed a curiosity about astronomy stimulated by a friend's interest. His father bought him a telescope and he used it to systematically record sunspots, and later attempted to make a larger 6-inch reflector, a project left uncompleted. As a teenager Allan read widely, especially astronomy books of all kinds, recalling in particular The Glass Giant of Palomar as well as popular works by Eddington and Hubble (The Realm of the Nebulae) in the early 1940s. Although his family was Mormon, of the Reorganized Church, he was not practicing, though he later sporadically attended a Methodist church in Oxford, Iowa during his college years. Sandage knew by his high school years that he would engage in some form of intellectual life related to astronomy. He particularly recalls an influential science teacher at Miami University in Oxford, Ohio named Ray Edwards, who inspired him to think critically and "not settle for any hand-waving of any kind." [Interview of Allan Rex Sandage by Spencer

  8. 32. SCIENTISTS ALLAN COX (SEATED), RICHARD DOELL, AND BRENT DALRYMPLE ...

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

    32. SCIENTISTS ALLAN COX (SEATED), RICHARD DOELL, AND BRENT DALRYMPLE AT CONTROL PANEL, ABOUT 1965. - U.S. Geological Survey, Rock Magnetics Laboratory, 345 Middlefield Road, Menlo Park, San Mateo County, CA

  9. Allan Sandage and the distance scale

    NASA Astrophysics Data System (ADS)

    Tammann, G. A.; Reindl, B.

    2013-02-01

    Allan Sandage returned to the distance scale and the calibration of the Hubble constant again and again during his active life, experimenting with different distance indicators. In 1952 his proof of the high luminosity of Cepheids confirmed Baade's revision of the distance scale (H0 ~ 250 km s-1 Mpc-1). During the next 25 years, he lowered the value to 75 and 55. Upon the arrival of the Hubble Space Telescope, he observed Cepheids to calibrate the mean luminosity of nearby Type Ia supernovae (SNe Ia) which, used as standard candles, led to the cosmic value of H0 = 62.3 +/- 1.3 +/- 5.0 km s-1 Mpc-1. Eventually he turned to the tip of the red giant branch (TRGB) as a very powerful distance indicator. A compilation of 176 TRGB distances yielded a mean, very local value of H0 = 62.9 +/- 1.6 km s-1 Mpc-1 and shed light on the streaming velocities in the Local Supercluster. Moreover, TRGB distances are now available for six SNe Ia; if their mean luminosity is applied to distant SNe Ia, one obtains H0 = 64.6 +/- 1.6 +/- 2.0 km s-1 Mpc-1. The weighted mean of the two independent large-scale calibrations yields H0 = 64.1 km s-1 Mpc-1 within 3.6%.

  10. Allan deviation analysis of financial return series

    NASA Astrophysics Data System (ADS)

    Hernández-Pérez, R.

    2012-05-01

    We perform a scaling analysis for the return series of different financial assets applying the Allan deviation (ADEV), which is used in the time and frequency metrology to characterize quantitatively the stability of frequency standards since it has demonstrated to be a robust quantity to analyze fluctuations of non-stationary time series for different observation intervals. The data used are opening price daily series for assets from different markets during a time span of around ten years. We found that the ADEV results for the return series at short scales resemble those expected for an uncorrelated series, consistent with the efficient market hypothesis. On the other hand, the ADEV results for absolute return series for short scales (first one or two decades) decrease following approximately a scaling relation up to a point that is different for almost each asset, after which the ADEV deviates from scaling, which suggests that the presence of clustering, long-range dependence and non-stationarity signatures in the series drive the results for large observation intervals.

  11. The late Little Ice Age landslide calamity in North Bohemia: Triggers, impacts and post-landslide development reconstructed from documentary data (case study of the Kozí vrch Hill landslide)

    NASA Astrophysics Data System (ADS)

    Raška, Pavel; Zábranský, Vilém; Brázdil, Rudolf; Lamková, Jana

    2016-02-01

    The beginning of the 1770s in the Czech Lands is well documented for its meteorological extremes and their social impacts. However, the effects of these extremes on geomorphic systems and on landslide occurrence and activity in particular have been minimally studied. In this paper, we use a complex set of written and iconographic documentary data to reconstruct the landslide calamity in North Bohemia, with a detailed case study of the Kozí vrch Hill landslide. The landslide calamity of 1770 is the oldest known landslide calamity in this region, including 14 documented events; and its reconstruction may therefore provide important data on landslide frequency, triggers, and impacts during the adverse weather patterns in the last part of the Little Ice Age (LIA). We focus on a case study of the Kozí vrch Hill landslide, and we use the documentary evidence and field techniques to reconstruct its location, extent, topography, kinematics, and triggers. Based on precipitation indices and weather descriptions, the extremely wet and rainy preceding year and the 1769/1770 winter were the major triggering factors that resulted in water saturation of Neogene volcaniclastics underlying the basalt lava flows and their subsequent collapse. Furthermore, we analyse the post-landslide terrain transformation and land use patterns during the 240 years following the landslide to illustrate the persistence of particular landslide features. We conclude that the major transformations, which obscured most of the landslide features, occurred in only the last 50-60 years. Finally, we discuss the role of documentary data and the current methodological advances in their use for the reconstruction of landslide frequency and impacts during the LIA.

  12. Obituary: Allan R. Sandage (1926-2010)

    NASA Astrophysics Data System (ADS)

    Devorkin, David

    2011-12-01

    Allan Rex Sandage died of pancreatic cancer at his home in San Gabriel, California, in the shadow of Mount Wilson, on November 13, 2010. Born in Iowa City, Iowa, on June 18, 1926, he was 84 years old at his death, leaving his wife, former astronomer Mary Connelly Sandage, and two sons, David and John. He also left a legacy to the world of astronomical knowledge that has long been universally admired and appreciated, making his name synonymous with late 20th-Century observational cosmology. The only child of Charles Harold Sandage, a professor of advertising who helped establish that academic specialty after obtaining a PhD in business administration, and Dorothy Briggs Sandage, whose father was president of Graceland College in Iowa, Allan Sandage grew up in a thoroughly intellectual, university oriented atmosphere but also a peripatetic one taking him to Philadelphia and later to Illinois as his father rose in his career. During his 2 years in Philadelphia, at about age eleven, Allan developed a curiosity about astronomy stimulated by a friend's interest. His father bought him a telescope and he used it to systematically record sunspots, and later attempted to make a larger 6-inch reflector, a project left uncompleted. As a teenager Allan read widely, especially astronomy books of all kinds, recalling in particular The Glass Giant of Palomar as well as popular works by Eddington and Hubble (The Realm of the Nebulae) in the early 1940s. Although his family was Mormon, of the Reorganized Church, he was not practicing, though he later sporadically attended a Methodist church in Oxford, Iowa during his college years. Sandage knew by his high school years that he would engage in some form of intellectual life related to astronomy. He particularly recalls an influential science teacher at Miami University in Oxford, Ohio named Ray Edwards, who inspired him to think critically and "not settle for any hand-waving of any kind." [Interview of Allan Rex Sandage by Spencer

  13. Refining LA-ICP-MS techniques for the exploration of ultra-thin layers in Alpine and Polar ice

    NASA Astrophysics Data System (ADS)

    Spaulding, Nicole; Bohleber, Pascal; Mayewski, Paul; Wagenbach, Dietmar; Kurbatov, Andrei; Sneed, Sharon; Handley, Mike; Erhardt, Tobias

    2015-04-01

    origin, archived in the CG ice core. Considering more broadly our findings from the CG ice and the refined characterization of our LA system, this technique promises to be of great benefit to the analysis of ultra-thin ice core layers. This may be especially relevant for members of the ice core community pursuing million year old ice kilometers below the surface. As such we also provide examples of LA analysis of deep polar ice from Greenland (GISP2) and shallow, yet ancient (up to 1 Mya), ice from the Allan Hills Blue Ice Area, Antarctica, which demonstrate how the insight gained from our study could be applied by the polar ice coring community.

  14. Allan Houser (Haozous) Santa Fe Compound and Sculpture Garden.

    ERIC Educational Resources Information Center

    Herberholz, Barbara

    1999-01-01

    Summarizes the life of artist Allan Houser focusing on his childhood and his family life, the development of his artistic endeavors, and his career as an artist. Comments on the Alan Houser Compound that is a 104-acre compound and sculpture garden that houses over 30 of his sculptures. (CMK)

  15. Numbers Of Degrees Of Freedom Of Allan-Variance Estimators

    NASA Technical Reports Server (NTRS)

    Greenhall, Charles A.

    1992-01-01

    Report discusses formulas for estimation of Allan variances. Presents algorithms for closed-form approximations of numbers of degrees of freedom characterizing results obtained when various estimators applied to five power-law components of classical mathematical model of clock noise.

  16. The Queensland "New Basics": An Interview with Allan Luke.

    ERIC Educational Resources Information Center

    Hunter, Lisa

    2001-01-01

    Presents an interview with Allan Luke, current editor of "The Journal of Adolescent and Adult Literacy," and Deputy Director General of Education for Queensland. Discusses several reform projects--Education 2010 (a futures-oriented analysis and philosophy for Queensland Schools); The New Basics ( a new curriculum/pedagogy/assessment framework);…

  17. Biotechnology Symposium - In Memoriam, the Late Dr. Allan Zipf

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A one-day biotechnology symposium was held at Alabama A&M University (AAMU), Normal, AL on June 4, 2004 in memory of the late Dr. Allan Zipf (Sept 1953-Jan 2004). Dr. Zipf was a Research Associate Professor at the Department of Plant and Soil Sciences, AAMU, who collaborated extensively with ARS/MS...

  18. Sulfur isotopic systematics in alteration assemblages in martian meteorite Allan Hills 84001

    SciTech Connect

    Shearer, C.K.; Layne, G.D.; Papike, J.J.; Spilde, M.N.

    1996-08-01

    ALH84001 is a coarse-grained, clastic orthopyroxenite meteorite related to the SNC meteorite group (shergottites, nakhlites, Chassigny). Superimposed upon the orthopyroxene-dominant igneous mineral assemblage is a hydrothermal signature. This hydrothermal overprint consists of carbonate assemblages occurring in spheroidal aggregates and fine-grained carbonate-sulfide vug-filling. The sulfide in this assemblage has been identified as pyrite, an unusual sulfide in meteorites. Previously, Burgess et al. (1989) reported a bulk {delta} {sup 34}S for a SNC group meteorite (Shergotty) of -0.5 {+-} 1.5%. Here, we report the first martian {delta} {sup 34}S values from individual sulfide grains. Using newly developed ion microprobe techniques, we were able to determine {delta} {sup 34}S of the pyrite in ALH84001 with a 1 {alpha} precision of better than {+-}0.5%. The {delta} {sup 34}S values for the pyrite range from +4.8 to +7.8%. Within the stated uncertainties, the pyrite from ALH84001 exhibits a real variability in {delta} {sup 34}S in this alteration assemblage. In addition, these sulfides are demonstrably enriched in {sup 34}S relative to Canon Diablo troilite and sulfides from most other meteorites. This signature implies that the planetary body represented by ALH 84001 experienced processes capable of fractionating sulphur isotopes and that hydrothermal conditions changed during pyrite precipitation (T, pH, fluid composition, etc.). These new data are not consistent with the pyrite recording either biogenic activity or atmospheric fractionation of sulphur through nonthermal escape mechanisms or oxidation processes. This study also demonstrates the usefulness of ion microprobe measurements of sulphur isotopes in constraining conditions on other planetary bodies.

  19. Cumberland Falls chondritic inclusions. III - Consortium study of relationship to inclusions in Allan Hills 78113 aubrite

    NASA Technical Reports Server (NTRS)

    Lipschutz, Michael E.; Verkouteren, R. Michael; Sears, Derek W. G.; Hasan, Fouad A.; Prinz, Martin

    1988-01-01

    The contents of Ag, Au, Bi, Cd, Co, Cs, Ga, In, Rb, Sb, Se, Te, Tl, U, and Zn in large chondritic clasts from the Cumbersand Falls aubrite were determined by radiochemical neutron activation analysis, and the results, together with the results of a mineralogical investigation, were compared with respective data obtained for three primitive inclusions from the ALH A78113 aubrite. The results indicated that the clasts from both aubrite sources constitute a single chondritic suite. The analyses data, together with the results of thermoluminescence data for Cumberland Falls chondritic inclusions and achondritic host, indicate that inclusions in Cumberland Falls and in ALH A78113 aubrite represent a primitive chondrite sample suite whose properties were established during primary nebular accretion and condensation over a broad redox range.

  20. Biogenic or Abiogenic Origin of Carbonate-Magnetite-Sulfide Assemblages in Martian Meteorite Allan Hills 84001

    NASA Astrophysics Data System (ADS)

    Scott, E. R. D.

    1998-01-01

    It has been suggested that the carbonates and submicrometer grains of magnetite, pyrrhotite, and an Fe-S phase identified as "probably griegite" were all biogenic in origin. Their arguments were based on similarities in the compositions, structures, shapes, and sizes of these minerals with terrestrial bio-minerals and the apparent absence of plausible abiogenic origins. Here we compare the carbonate assemblages to possible martian, terrestrial, and meteoritic analogs and discuss new and published arguments for and against abiogenic and biogenic origins for these minerals.

  1. Cumberland Falls chondritic inclusions: III. Consortium study of relationship to inclusions in Allan Hills 78113 aubrite

    SciTech Connect

    Lipschutz, M.E.; Verkouteren, R.M. ); Sears, D.W.G.; Hasan, F.A. ); Prinz, M.; Weisberg, M.K.; Nehru, C.E.; Delaney, J.S. ); Grossman, L.; Boily, M. )

    1988-07-01

    The authors describe the mineralogy and report contents of Ag, Au, Bi, Cd, Co, Cs, Ga, In, Rb, Sb, Se, Te, Tl, U and Zn determined by RNAA in three primitive chondritic inclusions from the ALH A78113 aubrite. Comparison of these data with those for large, petrologic type 3 chondritic clasts from the Cumberland Falls aubrite and the discovery of small clasts in it like those in ALH A78113 indicate that all constitute a single chondritic suite. They report thermoluminescence data for Cumberland Falls chondritic inclusions and achondritic host. These results, together with mineralogic, major, minor and trace element information, demonstrate that aubrite inclusions represent a different sort of type 3 chondrite, not an LL3 chondrite altered during equilibration with aubrite host. Instead, the aubrite inclusions represent a distinct chondrite class. These inclusions reflect nebular condensation/accretion over a broad redox range and at temperatures relatively high compared with those at which other type 3 chondrites formed. Limited metamorphism and reduction occurred during condensation/accretion, prior to incorporation into aubrite host. During the impact of the chondritic parent body with the aubrite parent body, chondrite fragments were strongly shocked and cooled rapidly. They then mixed with aubrite host, possibly in a regolith, so that these aubrites now represent impact breccias.

  2. Rare Potassium-Bearing Mica in Allan Hills 84001: Additional Constraints on Carbonate Formation

    NASA Technical Reports Server (NTRS)

    Brearley, A. J.

    1998-01-01

    There have been presented several intriguing observations suggesting evidence of fossil life in martian orthopyroxenite ALH 84001. These exciting and controversial observations have stimulated extensive debate over the origin and history of ALH 84001, but many issues still remain unresolved. Among the most important is the question of the temperature at which the carbonates, which host the putative microfossils, formed. Oxygen- isotopic data, while showing that the carbonates are generally out of isotopic equilibria with the host rock, cannot constrain their temperature of formation. Both low- and high-temperature scenarios are plausible depending on whether carbonate growth occurred in an open or closed system. Petrographic arguments have generally been used to support a high-temperature origin but these appear to be suspect because they assume equilibrium between carbonate compositions that are not in contact. Some observations appear to be consistent with shock mobilization and growth from immiscible silicate-carbonate melts at high temperatures. Proponents of a low-temperature origin for the carbonates are hampered by the fact that there is currently no evidence of hydrous phases that would indicate low temperatures and the presence of a hydrous fluid during the formation of the carbonates. However, the absence of hydrous phases does not rule out carbonate formation at low temperatures, because the carbonate forming fluids may have been extremely CO2 rich, such that hydrous phases would not have been stabilized. In this study, I have carried out additional Transmission electron microscopy (TEM) studies of ALH-84001 and have found evidence of very rare phyllosilicates, which appear to be convincingly of pre-terrestrial origin. At present these observations are limited to one occurrence: further studies are in progress to determine if the phyllosilicates are more widespread.

  3. Polycyclic aromatic hydrocarbons (PAHs) in Antarctic Martian meteorites, carbonaceous chondrites, and polar ice.

    PubMed

    Becker, L; Glavin, D P; Bada, J L

    1997-01-01

    Recent analyses of the carbonate globules present in the Martian meteorite ALH84001 have detected polycyclic aromatic hydrocarbons (PAHs) at the ppm level (McKay et al., 1996). The distribution of PAHs observed in ALH84001 was interpreted as being inconsistent with a terrestrial origin and were claimed to be indigenous to the meteorite, perhaps derived from an ancient martian biota. We have examined PAHs in the Antarctic shergottite EETA79001, which is also considered to be from Mars, as well as several Antarctic carbonaceous chondrites. We have found that many of the same PAHs detected in the ALH84001 carbonate globules are present in Antarctic carbonaceous chondrites and in both the matrix and carbonate (druse) component of EETA79001. We also investigated PAHs in polar ice and found that carbonate is an effective scavenger of PAHs in ice meltwater. Moreover, the distribution of PAHs in the carbonate extract of Antarctic Allan Hills ice is remarkably similar to that found in both EETA79001 and ALH84001. The reported presence of L-amino acids of apparent terrestrial origin in the EETA79001 druse material (McDonald and Bada, 1995) suggests that this meteorite is contaminated with terrestrial organics probably derived from Antarctic ice meltwater that had percolated through the meteorite. Our data suggests that the PAHs observed in both ALH84001 and EETA79001 are derived from either the exogenous delivery of organics to Mars or extraterrestrial and terrestrial PAHs present in the ice meltwater or, more likely, from a mixture of these sources. It would appear that PAHs are not useful biomarkers in the search for extinct or extant life on Mars. PMID:11541466

  4. Polycyclic aromatic hydrocarbons (PAHs) in Antarctic Martian meteorites, carbonaceous chondrites, and polar ice

    SciTech Connect

    Becker, L. |; Glavin, D.P.; Bada, J.L.

    1997-01-01

    Recent analyses of the carbonate globules present in the Martian meteorite ALH84001 have detected polycyclic aromatic hydrocarbons (PAHs) at the ppm level. The distribution of PAHs observed in ALH84001 was interpreted as being inconsistent with a terrestrial origin and were claimed to be indigenous to the meteorite, perhaps derived from an ancient martian biota. We have examined PAHs in the Antarctic shergottite EETA79001, which is also considered to be from Mars, as well as several Antarctic carbonaceous chondrites. We have found that many of the same PAHs detected in the ALH84001 carbonate globules are present in Antarctic carbonaceous chondrites and in both the matrix and carbonate (druse) component of EETA79001. We also investigated PAHs in polar ice and found that carbonate is an effective scavenger of PAHs in ice meltwater. Moreover, the distribution of PAHs in the carbonate extract of Antarctic Allan Hills ice is remarkably similar to that found in both EETA79001 and ALH84001. The reported presence of L-amino acids of apparent terrestrial origin in the EETA79001 druse material suggests that this meteorite is contaminated with terrestrial organics probably derived from Antarctic ice meltwater that had percolated through the meteorite. Our data suggests that the PAHs observed in both ALH84001 and EETA79001 are derived from either the exogenous delivery of organics to Mars or extraterrestrial and terrestrial PAHs present in the ice meltwater or, more likely, from a mixture of these sources. It would appear that PAHs are not useful biomarkers in the search for extinct or extant life on Mars. 33 refs., 3 figs., 1 tab.

  5. Possible Meteorites in the Martian Hills (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    From its winter outpost at 'Low Ridge' inside Gusev Crater, NASA's Mars Exploration Rover Spirit took this spectacular, color mosaic of hilly, sandy terrain and two potential iron meteorites. The two light-colored, smooth rocks about two-thirds of the way up from the bottom of the frame have been labeled 'Zhong Shan' and 'Allan Hills.'

    The two rocks' informal names are in keeping with the rover science team's campaign to nickname rocks and soils in the area after locations in Antarctica. Zhong Shang is an Antarctic base that the People's Republic of China opened on Feb. 26, 1989, at the Larsemann Hills in Prydz Bay in East Antarctica. Allan Hills is a location where researchers have found many Martian meteorites, including the controversial ALH84001, which achieved fame in 1996 when NASA scientists suggested that it might contain evidence for fossilized extraterrestrial life. Zhong Shan was the given name of Dr. Sun Yat-sen (1866-1925), known as the 'Father of Modern China.' Born to a peasant family in Guangdong, Sun moved to live with his brother in Honolulu at age 13 and later became a medical doctor. He led a series of uprisings against the Qing dynasty that began in 1894 and eventually succeeded in 1911. Sun served as the first provisional president when the Republic of China was founded in 1912.

    The Zhong Shan and Allan Hills rocks, at the left and right, respectively, have unusual morphologies and miniature thermal emission spectrometer signatures that resemble those of a rock known as 'Heat Shield' at the Meridiani site explored by Spirit's twin, Opportunity. Opportunity's analyses revealed Heat Shield to be an iron meteorite.

    Spirit acquired this false-color image on the rover's 872nd Martian day, or sol (June 16, 2006), using exposures taken through three of the panoramic camera's filters, centered on wavelengths of 750 nanometers, 530 nanometers, and 430 nanometers. The image is presented in false color to emphasize differences among

  6. The Third-Difference Approach to Modified Allan Variance

    NASA Technical Reports Server (NTRS)

    Greenhall, C. A.

    1995-01-01

    This study gives strategies for estimating the modified Allan variance (mvar) and formulas for computing the equivalent degrees of freedom (edf) of the estimators. A third-difference formulation of mvar leads to a tractable formula for edf in the presence of power-law phase noise. The effect of estimation stride on edf is tabulated. First-degree rational-function approximations for edf are derived.

  7. Relationship between Allan variances and Kalman Filter parameters

    NASA Technical Reports Server (NTRS)

    Vandierendonck, A. J.; Mcgraw, J. B.; Brown, R. G.

    1984-01-01

    A relationship was constructed between the Allan variance parameters (H sub z, H sub 1, H sub 0, H sub -1 and H sub -2) and a Kalman Filter model that would be used to estimate and predict clock phase, frequency and frequency drift. To start with the meaning of those Allan Variance parameters and how they are arrived at for a given frequency source is reviewed. Although a subset of these parameters is arrived at by measuring phase as a function of time rather than as a spectral density, they all represent phase noise spectral density coefficients, though not necessarily that of a rational spectral density. The phase noise spectral density is then transformed into a time domain covariance model which can then be used to derive the Kalman Filter model parameters. Simulation results of that covariance model are presented and compared to clock uncertainties predicted by Allan variance parameters. A two state Kalman Filter model is then derived and the significance of each state is explained.

  8. Measurement of Allan variance and phase noise at fractions of a millihertz

    NASA Technical Reports Server (NTRS)

    Conroy, Bruce L.; Le, Duc

    1990-01-01

    Although the measurement of Allan variance of oscillators is well documented, there is a need for a simplified system for finding the degradation of phase noise and Allan variance step-by-step through a system. This article describes an instrumentation system for simultaneous measurement of additive phase noise and degradation in Allan variance through a transmitter system. Also included are measurements of a 20-kW X-band transmitter showing the effect of adding a pass tube regulator.

  9. The dynamic Allan Variance IV: characterization of atomic clock anomalies.

    PubMed

    Galleani, Lorenzo; Tavella, Patrizia

    2015-05-01

    The number of applications where precise clocks play a key role is steadily increasing, satellite navigation being the main example. Precise clock anomalies are hence critical events, and their characterization is a fundamental problem. When an anomaly occurs, the clock stability changes with time, and this variation can be characterized with the dynamic Allan variance (DAVAR). We obtain the DAVAR for a series of common clock anomalies, namely, a sinusoidal term, a phase jump, a frequency jump, and a sudden change in the clock noise variance. These anomalies are particularly common in space clocks. Our analytic results clarify how the clock stability changes during these anomalies. PMID:25965674

  10. A Simple Algorithm for Approximating Confidence on the Modified Allan Variance and the Time Variance

    NASA Technical Reports Server (NTRS)

    Weiss, Marc A.; Greenhall, Charles A.

    1996-01-01

    An approximating algorithm for computing equvalent degrees of freedom of the Modified Allan Variance and its square root, the Modified Allan Deviation (MVAR and MDEV), and the Time Variance and Time Deviation (TVAR and TDEV) is presented, along with an algorithm for approximating the inverse chi-square distribution.

  11. Pragmatics: The State of the Art: An Online Interview with Keith Allan

    ERIC Educational Resources Information Center

    Allan, Keith; Salmani Nodoushan, Mohammad Ali

    2015-01-01

    This interview was conducted with Professor Keith Allan with the aim of providing a brief but informative summary of the state of the art of pragmatics. In providing answers to the interview questions, Professor Allan begins with a definition of pragmatics as it is practiced today, i.e., the study of the meanings of utterances with attention to…

  12. Glacial History of the Pirrit Hills, West Antarctica

    NASA Astrophysics Data System (ADS)

    Spector, P. E.; Stone, J. O.

    2014-12-01

    We present new ice-thickness constraints from the Pirrit Hills, a small, far-flung group of nunataks located in the Weddell Sector. At the Pirrit Hills, fresh glacial erratics indicate ice levels ~350-450 m above present during the last ice age. The highest erratics have preliminary 10Be exposure ages of ~16 ka, and the ages generally decrease with decreasing elevation, recording the thinning of the ice in the region. Despite the evidence of thicker ice, weathered bedrock extends down to the present ice level, implying prolonged subaerial weathering prior to the last ice age. These features, and the lack of evidence for wet-based glacial erosion, indicate cold-based and non-erosive ice cover. Over the elevation range in which we found glacial erratics, bedrock 10Be, 26Al, and 21Ne concentrations are consistent with modest ice cover, and have exposure ages ranging from ~0.3-1.5 Myr. Around 450 m above the present ice level, bedrock 10Be, 26Al, and 21Ne concentrations increase by a factor of ~4-5 and do not indicate past ice cover. This height coincides with a break in the otherwise steep slopes of the Pirrit Hills, and the bedrock above is more weathered than the bedrock below. This transition marks the height above which ice cover, if it has occurred in the past few million years, has been very rare, brief, and cold-based. This feature may relate to the trimline imprinted on ridges in the Ellsworth Mountains. In both cases, alpine landscapes have been preserved by a polar climate and glacial highstands rising only partway up the mountain flanks.

  13. Princess Marie Bonaparte, Edgar Allan Poe, and psychobiography.

    PubMed

    Warner, S L

    1991-01-01

    Princess Marie Bonaparte was a colorful yet mysterious member of Freud's inner circle of psychoanalysis. In analysis with Freud beginning in 1925 (she was then 45 years old), she became a lay analyst and writer of many papers and books. Her most ambitious task was a 700-page psychobiography of Edgar Allan Poe that was first published in French in 1933. She was fascinated by Poe's gothic stories--with the return to life of dead persons and the eerie, unexpected turns of events. Her fascination with Poe can be traced to the similarity of their early traumatic life experiences. Bonaparte had lost her mother a month after her birth. Poe's father deserted the family when Edgar was two years old, and his mother died of tuberculosis when he was three. Poe's stories helped him to accommodate to these early traumatic losses. Bonaparte vicariously shared in Poe's loss and the fantasies of the return of the deceased parent in his stories. She was sensitive and empathetic to Poe's inner world because her inner world was similar. The result of this psychological fit between Poe and Bonaparte was her psychobiography, The Life and Works of Edgar Allan Poe. It was a milestone in psychobiography but limited in its psychological scope by its strong emphasis on early childhood trauma. Nevertheless it proved Bonaparte a bona fide creative psychoanalyst and not a dilettante propped up by her friendship with Freud. PMID:1744021

  14. Allan Deviation Plot as a Tool for Quartz-Enhanced Photoacoustic Sensors Noise Analysis.

    PubMed

    Giglio, Marilena; Patimisco, Pietro; Sampaolo, Angelo; Scamarcio, Gaetano; Tittel, Frank K; Spagnolo, Vincenzo

    2016-04-01

    We report here on the use of the Allan deviation plot to analyze the long-term stability of a quartz-enhanced photoacoustic (QEPAS) gas sensor. The Allan plot provides information about the optimum averaging time for the QEPAS signal and allows the prediction of its ultimate detection limit. The Allan deviation can also be used to determine the main sources of noise coming from the individual components of the sensor. Quartz tuning fork thermal noise dominates for integration times up to 275 s, whereas at longer averaging times, the main contribution to the sensor noise originates from laser power instabilities. PMID:26529758

  15. Seizures in the life and works of Edgar Allan Poe.

    PubMed

    Bazil, C W

    1999-06-01

    Edgar Allan Poe, one of the most celebrated of American storytellers, lived through and wrote descriptions of episodic unconsciousness, confusion, and paranoia. These symptoms have been attributed to alcohol or drug abuse but also could represent complex partial seizures, prolonged postictal states, or postictal psychosis. Complex partial seizures were not well described in Poe's time, which could explain a misdiagnosis. Alternatively, he may have suffered from complex partial epilepsy that was complicated or caused by substance abuse. Even today, persons who have epilepsy are mistaken for substance abusers and occasionally are arrested during postictal confusional states. Poe was able to use creative genius and experiences from illness to create memorable tales and poignant poems. PMID:10369317

  16. Europa Ridges, Hills and Domes

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This moderate-resolution view of the surface of one of Jupiter's moons, Europa, shows the complex icy crust that has been extensively modified by fracturing and the formation of ridges. The ridge systems superficially resemble highway networks with overpasses, interchanges and junctions. From the relative position of the overlaps, it is possible to determine the age sequence for the ridge sets. For example, while the 8-kilometer-wide (5-mile) ridge set in the lower left corner is younger than most of the terrain seen in this picture, a narrow band cuts across the set toward the bottom of the picture, indicating that the band formed later. In turn, this band is cut by the narrow 2- kilometer-wide (1.2-mile) double ridge running from the lower right to upper left corner of the picture. Also visible are numerous clusters of hills and low domes as large as 9 kilometers (5.5 miles) across, many with associated dark patches of non-ice material. The ridges, hills and domes are considered to be ice-rich material derived from the subsurface. These are some of the youngest features seen on the surface of Europa and could represent geologically young eruptions.

    This area covers about 140 kilometers by 130 kilometers (87 miles by 81 miles) and is centered at 12.3 degrees north latitude, 268 degrees west longitude. Illumination is from the east (right side of picture). The resolution is about 180 meters (200 yards) per pixel, meaning that the smallest feature visible is about a city block in size. The picture was taken by the Solid State Imaging system on board the Galileo spacecraft on February 20, 1997, from a distance of 17,700 kilometers (11,000 miles) during its sixth orbit around Jupiter.

    The Jet Propulsion Laboratory, Pasadena, CA, manages the mission for NASA's Office of Space Science, Washington D.C. This image and other images and data received from Galileo are posted on the World Wide Web Galileo mission home page at http://galileo.jpl.nasa.gov.

  17. On the application of Allan variance method for Ring Laser Gyro performance characterization

    SciTech Connect

    Ng, L.C.

    1993-10-15

    This report describes the method of Allan variance and its application to the characterization of a Ring Laser Gyro`s (RLG) performance. Allan variance, a time domain analysis technique, is an accepted IEEE standard for gyro specifications. The method was initially developed by David Allan of the National Bureau of Standards to quantify the error statistics of a Cesium beam frequency standard employed as the US Frequency Standards in 1960`s. The method can, in general, be applied to analyze the error characteristics of any precision measurement instrument. The key attribute of the method is that it allows for a finer, easier characterization and identification of error sources and their contribution to the overall noise statistics. This report presents an overview of the method, explains the relationship between Allan variance and power spectral density distribution of underlying noise sources, describes the batch and recursive implementation approaches, validates the Allan variance computation with a simulation model, and illustrates the Allan variance method using data collected from several Honeywell LIMU units.

  18. Radioactivities in returned lunar materials and in meteorites

    NASA Technical Reports Server (NTRS)

    Fireman, E. L.

    1984-01-01

    Carbon 14 terrestial ages were determined with low level minicomputers and accelerator mass spectrometry on 1 Yamato and 18 Allan Hills and nearby sited meteorites. Techniques for an accelerator mass spectrometer which make C(14) measurements on small samples were developed. Also Be(10) concentrations were measured in Byrd core and Allan Hills ice samples.

  19. Radial forcing and Edgar Allan Poe's lengthening pendulum

    NASA Astrophysics Data System (ADS)

    McMillan, Matthew; Blasing, David; Whitney, Heather M.

    2013-09-01

    Inspired by Edgar Allan Poe's The Pit and the Pendulum, we investigate a radially driven, lengthening pendulum. We first show that increasing the length of an undriven pendulum at a uniform rate does not amplify the oscillations in a manner consistent with the behavior of the scythe in Poe's story. We discuss parametric amplification and the transfer of energy (through the parameter of the pendulum's length) to the oscillating part of the system. In this manner, radial driving can easily and intuitively be understood, and the fundamental concept applied in many other areas. We propose and show by a numerical model that appropriately timed radial forcing can increase the oscillation amplitude in a manner consistent with Poe's story. Our analysis contributes a computational exploration of the complex harmonic motion that can result from radially driving a pendulum and sheds light on a mechanism by which oscillations can be amplified parametrically. These insights should prove especially valuable in the undergraduate physics classroom, where investigations into pendulums and oscillations are commonplace.

  20. Top of the hill.

    PubMed

    Lubell, Jennifer

    2009-08-24

    With healthcare reform the hottest topic in Washington (and at congressional town halls) this summer, it's no surprise President Barack Obama tops our 100 Most Powerful People in Healthcare ranking, joined by plenty of other power players on the Hill. "Clearly, the president is pushing hard on his goals to expand access to care, to reform health insurance and to control costs," says LifePoint's Bill Carpenter. PMID:19731430

  1. Nose Hill Artifacts

    ERIC Educational Resources Information Center

    Hansen, Vivian

    2008-01-01

    A Blackfoot woman, caught in the act of adultery, was condemned at this site to have her nose cut off as a penalty for her actions. People do not know her story. The tribe cast it on the ground. And so She, Nose Hill, was named. John Laurie Boulevard holds her mound in a circlet of asphalt, defining the map of her "terra incognita." She is a park…

  2. 'Columbia Hills' Oblique View

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Figure 1: Spirit's Long Journey, Sol 450

    This perspective view of a three-dimensional terrain model shows the shape of the 'Columbia Hills' landscape where NASA's Mars Exploration Rover Spirit has been working since mid-2004. North is toward the lower left. 'Husband Hill' is at the center, with the 'Inner Basin' behind it. This view is from images taken by the Mars Orbiter Camera on NASA's Mars Global Surveyor and processed into a three-dimensional terrain model by the U.S. Geological Survey.

    Spirit's Long Journey, Sol 450 More than 15 months after landing on Mars, NASA's Spirit rover is still going strong, having traveled a total of 4,276 meters (2.66 miles) as of martian day, or sol, 450 (April 8, 2005). This is a perspective view of the steepness of the 'Columbia Hills,' showing sites nicknamed 'Tennessee Valley,' 'Larry's Lookout,' 'Inner Basin,' 'Home Plate,' and the basin and summit beyond. This orbital view comprises images taken by the Mars Orbiter Camera on NASA's Mars Global Surveyor and processed by the U.S. Geological Survey as a three-dimensional terrain model.

  3. Online Estimation of Allan Variance Coefficients Based on a Neural-Extended Kalman Filter

    PubMed Central

    Miao, Zhiyong; Shen, Feng; Xu, Dingjie; He, Kunpeng; Tian, Chunmiao

    2015-01-01

    As a noise analysis method for inertial sensors, the traditional Allan variance method requires the storage of a large amount of data and manual analysis for an Allan variance graph. Although the existing online estimation methods avoid the storage of data and the painful procedure of drawing slope lines for estimation, they require complex transformations and even cause errors during the modeling of dynamic Allan variance. To solve these problems, first, a new state-space model that directly models the stochastic errors to obtain a nonlinear state-space model was established for inertial sensors. Then, a neural-extended Kalman filter algorithm was used to estimate the Allan variance coefficients. The real noises of an ADIS16405 IMU and fiber optic gyro-sensors were analyzed by the proposed method and traditional methods. The experimental results show that the proposed method is more suitable to estimate the Allan variance coefficients than the traditional methods. Moreover, the proposed method effectively avoids the storage of data and can be easily implemented using an online processor. PMID:25625903

  4. Online estimation of Allan variance coefficients based on a neural-extended Kalman filter.

    PubMed

    Miao, Zhiyong; Shen, Feng; Xu, Dingjie; He, Kunpeng; Tian, Chunmiao

    2015-01-01

    As a noise analysis method for inertial sensors, the traditional Allan variance method requires the storage of a large amount of data and manual analysis for an Allan variance graph. Although the existing online estimation methods avoid the storage of data and the painful procedure of drawing slope lines for estimation, they require complex transformations and even cause errors during the modeling of dynamic Allan variance. To solve these problems, first, a new state-space model that directly models the stochastic errors to obtain a nonlinear state-space model was established for inertial sensors. Then, a neural-extended Kalman filter algorithm was used to estimate the Allan variance coefficients. The real noises of an ADIS16405 IMU and fiber optic gyro-sensors were analyzed by the proposed method and traditional methods. The experimental results show that the proposed method is more suitable to estimate the Allan variance coefficients than the traditional methods. Moreover, the proposed method effectively avoids the storage of data and can be easily implemented using an online processor. PMID:25625903

  5. 'Columbia Hills' from Orbit

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This view of the 'Columbia Hills' in Gusev Crater was made by draping an image from the Mars Orbiter Camera on NASA's Mars Global Surveyor orbiter (image E0300012 from that camera) over a digital elevation model that was derived from two Mars Orbiter Camera images (E0300012 and R0200357).

    This unique view is helpful to the rover team members as they plan the journey of NASA's Mars Exploration Rover Spirit to the base of the Columbia Hills and beyond. Spirit successfully completed a three-month primary mission, and so far remains healthy in an extended mission of bonus exploration. As of sol 135 (on May 21, 2004), Spirit sits approximately 680 meters (0.4 miles) away from its first target at the western base of the hills, a spot informally called 'West Spur.' The team estimates that Spirit will reach West Spur by sol 146 (June 1, 2004). Spirit will most likely remain there for about a week to study the outcrops and rocks associated with this location.

    When done there, Spirit will head approximately 620 meters (0.38 miles) to a higher-elevation location informally called 'Lookout Point.' Spirit might reach Lookout Point by around sol 165 (June 20, 2004). On the way, the rover will pass by and study ripple-shaped wind deposits that may reveal more information about wind processes on Mars.

    Lookout Point will provide a great vantage point for scientists to remotely study the inner basin area of the Columbia Hills. This basin contains a broad range of interesting geological targets including the informally named 'Home Plate' and other possible layered outcrops. These features suggest that the hills contain rock layers. Spirit might investigate the layers to determine whether they are water-deposited sedimentary rock.

    Once at Lookout Point, Spirit will acquire 360-degree panoramic images of the entire area to help define the rover's next steps. Assuming the rover stays healthy, Spirit will eventually drive down into the basin to get an up

  6. Mineralization of Bacteria in Terrestrial Basaltic Rocks: Comparison With Possible Biogenic Features in Martian Meteorite Allan Hills 84001

    NASA Technical Reports Server (NTRS)

    Thomas-Keprta, K. L.; McKay, D. S.; Wentworth, S. J.; Stevens, T. O.; Taunton, A. E.; Allen, C. C.; Gibson, E. K., Jr.; Romanek, C. S.

    1998-01-01

    The identification of biogenic features altered by diagenesis or mineralization is important in determining whether specific features in terrestrial rocks and in meteorites may have a biogenic origin. Unfortunately, few studies have addressed the formation of biogenic features in igneous rocks, which may be important to these phenomena, including the controversy over possible biogenic features in basaltic martian meteorite ALH84001. To explore the presence of biogenic features in igneous rocks, we examined microcosms growing in basaltic small-scale experimental growth chambers or microcosms. Microbial communities were harvested from aquifers of the Columbia River Basalt (CRB) group and grown in a microcosm containing unweathered basalt chips and groundwater (technique described in. These microcosms simulated natural growth conditions in the deep subsurface of the CRB, which should be a good terrestrial analog for any putative martian subsurface ecosystem that may have once included ALH84001. Here we present new size measurements and photomicrographs comparing the putative martian fossils to biogenic material in the CRB microcosms. The range of size and shapes of the biogenic features on the CRB microcosm chips overlaps with and is similar to those on ALH84001 chips. Although this present work does not provide evidence for the biogenicity of ALH84001 features, we believe that, based on criteria of size, shape, and general morphology, a biogenic interpretation for the ALH84001 features remains plausible.

  7. How do the Properties of Allan Hills 84001 Compare With Accepted Criteria for Evidence of Ancient Life?

    NASA Technical Reports Server (NTRS)

    Gibson, E. K., Jr.; McKay, D. S.; Thomas-Keprta, K.; Westall, F.; Romanek, C. A.

    1998-01-01

    Criteria for Past Life: To be confident that any sample contains evidence of past life or biogenic activity, one must determine beyond a shadow of a doubt that certain well-established features or biomarker signatures are present in the sample. In the case of martian samples, the criteria for past life have not been established because if life existed on the planet, we have no way of knowing its detailed characteristics. Lacking independent evidence about the nature of possible past life on Mars, the scientific community must use, for the time being, the criteria established for ancient samples from the Earth: (1) Do we know the geologic context of the sample? Is it compatible with past life? (2) Do we know the age of the sample and its stratigraphic location? Are they understood enough to relate possible life to geologic history? (3) Does the sample contain evidence of cellular morphology? (4) What structural remains of colonies or communities exist within the samples? (5) Is there any evidence of biominerals showing chemical or mineral disequilibria? (6) Is there any evidence of stable isotope patterns unique to biology? (7) Are there any organic biomarkers present? (8) Are the features indigenous to the sample? For acceptance of past life in a geologic sample, essentially all of these criteria must he met.

  8. Application of Allan Deviation to Assessing Uncertainties of Continuous-measurement Instruments, and Optimizing Calibration Schemes

    NASA Astrophysics Data System (ADS)

    Jacobson, Gloria; Rella, Chris; Farinas, Alejandro

    2014-05-01

    Technological advancement of instrumentation in atmospheric and other geoscience disciplines over the past decade has lead to a shift from discrete sample analysis to continuous, in-situ monitoring. Standard error analysis used for discrete measurements is not sufficient to assess and compare the error contribution of noise and drift from continuous-measurement instruments, and a different statistical analysis approach should be applied. The Allan standard deviation analysis technique developed for atomic clock stability assessment by David W. Allan [1] can be effectively and gainfully applied to continuous measurement instruments. As an example, P. Werle et al has applied these techniques to look at signal averaging for atmospheric monitoring by Tunable Diode-Laser Absorption Spectroscopy (TDLAS) [2]. This presentation will build on, and translate prior foundational publications to provide contextual definitions and guidelines for the practical application of this analysis technique to continuous scientific measurements. The specific example of a Picarro G2401 Cavity Ringdown Spectroscopy (CRDS) analyzer used for continuous, atmospheric monitoring of CO2, CH4 and CO will be used to define the basics features the Allan deviation, assess factors affecting the analysis, and explore the time-series to Allan deviation plot translation for different types of instrument noise (white noise, linear drift, and interpolated data). In addition, the useful application of using an Allan deviation to optimize and predict the performance of different calibration schemes will be presented. Even though this presentation will use the specific example of the Picarro G2401 CRDS Analyzer for atmospheric monitoring, the objective is to present the information such that it can be successfully applied to other instrument sets and disciplines. [1] D.W. Allan, "Statistics of Atomic Frequency Standards," Proc, IEEE, vol. 54, pp 221-230, Feb 1966 [2] P. Werle, R. Miicke, F. Slemr, "The Limits

  9. KISATCHIE HILLS WILDERNESS, LOUISIANA.

    USGS Publications Warehouse

    Haley, Boyd R.; Ryan, George S.

    1984-01-01

    A mineral-resource survey of the Kisatchie Hills Wilderness, Louisiana indicated little promise for the occurrence of mineral resources. There is insufficient data on oil and gas producing formations that underlie the area to evaluate the oil and gas resource potential. All the oil fields of Wilcox age are less than 40 acres in extent; therefore, closer spaced deeper wells might find additional fields in sediments of Wilcox age. Oil and natural gas have been produced from older reservoirs (Cretaceous age) to the northwest of the wilderness, and deeper wells might find oil and natural gas in sediments of Cretaceous and older age in the vicinity of the wilderness.

  10. Cooperativity: over the Hill.

    PubMed

    Forsén, S; Linse, S

    1995-12-01

    Cooperativity, the ability of ligand binding at one site on a macromolecule to influence ligand binding at a different site on the same macromolecule, is a fascinating biological property that is often poorly explained in textbooks. The Hill coefficient is commonly used in biophysical studies of cooperative systems although it is not a quantitative measure of cooperativity. The free energy of interaction between binding sites (delta delta G) is a more stringent definition of cooperativity and provides a direct quantitative measure of how the binding of ligand at one site affects the ligand affinity of another site. PMID:8571449

  11. The Art of George Morrison and Allan Houser: The Development and Impact of Native Modernism

    ERIC Educational Resources Information Center

    Montiel, Anya

    2005-01-01

    The idea for a retrospective on George Morrison and Allan Houser as one of the inaugural exhibitions at the National Museum of the American Indian (NMAI) came from the NMAI curator of contemporary art, Truman Lowe. An artist and sculptor himself, Lowe knew both artists personally and saw them as mentors and visionaries. Lowe advised an exhibition…

  12. Where Were the Whistleblowers? The Case of Allan McDonald and Roger Boisjoly.

    ERIC Educational Resources Information Center

    Stewart, Lea P.

    Employees who "blow the whistle" on their company because they believe it is engaged in practices that are illegal, immoral, or harmful to the public, often face grave consequences for their actions, including demotion, harassment, forced resignation, or termination. The case of Allan McDonald and Roger Boisjoly, engineers who blew the whistle on…

  13. Horror from the Soul--Gothic Style in Allan Poe's Horror Fictions

    ERIC Educational Resources Information Center

    Sun, Chunyan

    2015-01-01

    Edgar Allan Poe made tremendous contribution to horror fiction. Poe's inheritance of gothic fiction and American literature tradition combined with his living experience forms the background of his horror fictions. He inherited the tradition of the gothic fictions and made innovations on it, so as to penetrate to subconsciousness. Poe's horror…

  14. European Studies as Answer to Allan Bloom's "The Closing of the American Mind."

    ERIC Educational Resources Information Center

    Macdonald, Michael H.

    European studies can provide a solution to several of the issues raised in Allan Bloom's "The Closing of the American Mind." European studies pursue the academic quest for what is truth, what is goodness, and what is beauty. In seeking to answer these questions, the Greeks were among the first to explore many of humanity's problems and their…

  15. Allan M. Freedman, LLB: a lawyer’s gift to Canadian chiropractors

    PubMed Central

    Brown, Douglas M.

    2007-01-01

    This paper reviews the leadership role, contributions, accolades, and impact of Professor Allan Freedman through a 30 year history of service to CMCC and the chiropractic profession in Canada. Professor Freedman has served as an educator, philanthropist and also as legal counsel. His influence on chiropractic organizations and chiropractors during this significant period in the profession is discussed. PMID:18060008

  16. Observation, Inference, and Imagination: Elements of Edgar Allan Poe's Philosophy of Science

    ERIC Educational Resources Information Center

    Gelfert, Axel

    2014-01-01

    Edgar Allan Poe's standing as a literary figure, who drew on (and sometimes dabbled in) the scientific debates of his time, makes him an intriguing character for any exploration of the historical interrelationship between science, literature and philosophy. His sprawling "prose-poem" "Eureka" (1848), in particular, has…

  17. Allan deviation computations of a linear frequency synthesizer system using frequency domain techniques

    NASA Technical Reports Server (NTRS)

    Wu, Andy

    1995-01-01

    Allan Deviation computations of linear frequency synthesizer systems have been reported previously using real-time simulations. Even though it takes less time compared with the actual measurement, it is still very time consuming to compute the Allan Deviation for long sample times with the desired confidence level. Also noises, such as flicker phase noise and flicker frequency noise, can not be simulated precisely. The use of frequency domain techniques can overcome these drawbacks. In this paper the system error model of a fictitious linear frequency synthesizer is developed and its performance using a Cesium (Cs) atomic frequency standard (AFS) as a reference is evaluated using frequency domain techniques. For a linear timing system, the power spectral density at the system output can be computed with known system transfer functions and known power spectral densities from the input noise sources. The resulting power spectral density can then be used to compute the Allan Variance at the system output. Sensitivities of the Allan Variance at the system output to each of its independent input noises are obtained, and they are valuable for design trade-off and trouble-shooting.

  18. An Interview with Allan Wigfield: A Giant on Research on Expectancy Value, Motivation, and Reading Achievement

    ERIC Educational Resources Information Center

    Bembenutty, Hefer

    2012-01-01

    This article presents an interview with Allan Wigfield, professor and chair of the Department of Human Development and distinguished scholar-teacher at the University of Maryland. He has authored more than 100 peer-reviewed journal articles and book chapters on children's motivation and other topics. He is a fellow of Division 15 (Educational…

  19. Lost Hills, California Interferogram

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This figure shows a comparison of interferograms from four different years mapping the rapid ground subsidence over the Lost Hills oil field in California. Lost Hills is located about 60 km (40 miles) northwest of Bakersfield in the San Joaquin Valley. The oilfield is about 1.5 km (1 mile) wide and 6 km (3.5 miles) long. Each interferogram was created using pairs of images taken by synthetic aperture radar that have been combined to measure surface deformation or changes that may have occurred in the time between when data for the two images were taken. The images were collected by the European Space Agency's Remote Sensing satellites (ERS-1 and ERS-2) in two months of each year shown (1995, 1996, 1998 and 1999) and were combined to produce these image maps of the apparent surface deformation, or changes. The interferometric measurements that show the changes, primarily vertical subsidence of the surface, are rendered in color with purple indicating no motion and the brightest red showing rapid subsidence. The white areas are where the radar measurements could not be obtained, mostly in the agricultural fields around the oilfields where plant growth or plowing altered the radar properties of the surface. These radar data show that parts of the oilfield were subsiding unusually rapidly, more than 3 centimenters (1.2 inches) a month, in 1995 and 1996. They also reveal that while the ground subsidence rate decreased in the center part of the oilfield, it increased in the northern part between 1995 and 1996 and 1998 and 1999. Subsidence maps like these combined with records of oil and water extraction and injection will help scientist understand how the rocks within an oilfield are behaving, leading to improvements in oilfield operations. For more information, read Radar Helps Monitor Oil Fields. Images courtesy Eric Fielding, NASA Jet Propulsion Laboratory

  20. Lost Hills, California Interferogram

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This figure shows a comparison of interferograms from four different years mapping the rapid ground subsidence over the Lost Hills oil field in California. Lost Hills is located about 60 km (40 miles) northwest of Bakersfield in the San Joaquin Valley. The oil field is about 1.5 km (1mile) wide and 6 km (3.5 miles) long.

    Each interferogram was created using pairs of images taken by synthetic aperture radar that have been combined to measure surface deformation or changes that may have occurred in the time between when data for the two images were taken. The images were collected by the European Space Agency's Remote Sensing satellites (ERS-1 and ERS-2) in two months of each year shown (1995, 1996, 1998 and 1999) and were combined to produce these image maps of the apparent surface deformation, or changes.

    The interferometric measurements that show the changes, primarily vertical subsidence of the surface, are rendered in color with purple indicating no motion and the brightest red showing rapid subsidence. The white areas are where the radar measurements could not be obtained, mostly in the agricultural fields around the oil fields where plant growth or plowing altered the radar properties of the surface.

    These radar data show that parts of the oil field were subsiding unusually rapidly, more than 3 centimeters (1.2 inches) a month, in 1995 and 1996. They also reveal that while the ground subsidence rate decreased in the center part of the oil field, it increased in the northern part between 1995 and 1996 and 1998 and 1999.

    Subsidence maps like these combined with records of oil and water extraction and injection will help scientist understand how the rocks within an oil field are behaving, leading to improvements in oil field operations.

  1. 19. View of second floor of the Cherry Hill lettuce ...

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

    19. View of second floor of the Cherry Hill lettuce shed looking at door to stairwell - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  2. 18. View of the second floor of the Cherry Hill ...

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

    18. View of the second floor of the Cherry Hill lettuce shed looking at door - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  3. 15. Interior view of Cherry Hill lettuce shed showing posts ...

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

    15. Interior view of Cherry Hill lettuce shed showing posts looking towards the chute building - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  4. 20. View of second floor to the Cherry Hill lettuce ...

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

    20. View of second floor to the Cherry Hill lettuce shed looking at floor area - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  5. 14. Interior view of Cherry Hill lettuce shed looking towards ...

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

    14. Interior view of Cherry Hill lettuce shed looking towards chute building - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  6. 9. View of Cherry Hill lettuce shed looking north, with ...

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

    9. View of Cherry Hill lettuce shed looking north, with chute building on the left - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  7. 3. View of Cherry Hill lettuce shed looking southeast; parking ...

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

    3. View of Cherry Hill lettuce shed looking southeast; parking lot in foreground - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  8. 12. Partial view of Cherry Hill lettuce shed looking northwest ...

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

    12. Partial view of Cherry Hill lettuce shed looking northwest showing office - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  9. 2. Oblique view of Cherry Hill lettuce shed looking south; ...

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

    2. Oblique view of Cherry Hill lettuce shed looking south; chute building is in background - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  10. 6. Oblique view of Cherry Hill lettuce shed looking northeast, ...

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

    6. Oblique view of Cherry Hill lettuce shed looking northeast, with chute building to the right - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  11. 16. Interior view of Cherry Hill lettuce shed looking up ...

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

    16. Interior view of Cherry Hill lettuce shed looking up at the trusses of the second floor - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  12. 21. View of second floor of the Cherry Hill lettuce ...

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

    21. View of second floor of the Cherry Hill lettuce shed looking towards window - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  13. 22. View of second floor of the Cherry Hill lettuce ...

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

    22. View of second floor of the Cherry Hill lettuce shed looking at double doors - Richmond Hill Plantation, Cherry Hill Lettuce Shed, East of Richmond Hill on Ford Neck Road, Richmond Hill, Bryan County, GA

  14. On the Design of Attitude-Heading Reference Systems Using the Allan Variance.

    PubMed

    Hidalgo-Carrió, Javier; Arnold, Sascha; Poulakis, Pantelis

    2016-04-01

    The Allan variance is a method to characterize stochastic random processes. The technique was originally developed to characterize the stability of atomic clocks and has also been successfully applied to the characterization of inertial sensors. Inertial navigation systems (INS) can provide accurate results in a short time, which tend to rapidly degrade in longer time intervals. During the last decade, the performance of inertial sensors has significantly improved, particularly in terms of signal stability, mechanical robustness, and power consumption. The mass and volume of inertial sensors have also been significantly reduced, offering system-level design and accommodation advantages. This paper presents a complete methodology for the characterization and modeling of inertial sensors using the Allan variance, with direct application to navigation systems. Although the concept of sensor fusion is relatively straightforward, accurate characterization and sensor-information filtering is not a trivial task, yet they are essential for good performance. A complete and reproducible methodology utilizing the Allan variance, including all the intermediate steps, is described. An end-to-end (E2E) process for sensor-error characterization and modeling up to the final integration in the sensor-fusion scheme is explained in detail. The strength of this approach is demonstrated with representative tests on novel, high-grade inertial sensors. Experimental navigation results are presented from two distinct robotic applications: a planetary exploration rover prototype and an autonomous underwater vehicle (AUV). PMID:26800535

  15. Measurements of Ultra-Stable Oscillator (USO) Allan Deviations in Space

    NASA Technical Reports Server (NTRS)

    Enzer, Daphna G.; Klipstein, William M.; Wang, Rabi T.; Dunn, Charles E.

    2013-01-01

    Researchers have used data from the GRAIL mission to the Moon to make the first in-flight verification of ultra-stable oscillators (USOs) with Allan deviation below 10 13 for 1-to-100-second averaging times. USOs are flown in space to provide stable timing and/or navigation signals for a variety of different science and programmatic missions. The Gravity Recovery and Interior Laboratory (GRAIL) mission is flying twin spacecraft, each with its own USO and with a Ka-band crosslink used to measure range fluctuations. Data from this crosslink can be combined in such a way as to give the relative time offsets of the two spacecrafts USOs and to calculate the Allan deviation to describe the USOs combined performance while orbiting the Moon. Researchers find the first direct in-space Allan deviations below 10(exp -13) for 1-to-100-second averaging times comparable to pre-launch data, and better than measurements from ground tracking of an X-band carrier coherent with the USO. Fluctuations in Earth s atmosphere limit measurement performance in direct-to-Earth links. Inflight USO performance verification was also performed for GRAIL s parent mission, the Gravity Recovery and Climate Experiment (GRACE), using both Kband and Ka-band crosslinks.

  16. Soufriere Hills Volcano

    NASA Technical Reports Server (NTRS)

    2002-01-01

    In this ASTER image of Soufriere Hills Volcano on Montserrat in the Caribbean, continued eruptive activity is evident by the extensive smoke and ash plume streaming towards the west-southwest. Significant eruptive activity began in 1995, forcing the authorities to evacuate more than 7,000 of the island's original population of 11,000. The primary risk now is to the northern part of the island and to the airport. Small rockfalls and pyroclastic flows (ash, rock and hot gases) are common at this time due to continued growth of the dome at the volcano's summit.

    This image was acquired on October 29, 2002 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is

  17. Stratigraphic Relationships on Husband Hill, Mars

    NASA Astrophysics Data System (ADS)

    Cole, S. B.; Watters, W. A.; Squyres, S. W.

    2011-03-01

    We measure bedding plane orientations of outcrops on Cumberland Ridge in the Columbia Hills. Our measurements are consistent with the hypotheses that the outcrops (1) form a stratigraphic section, and (2) drape the Husband Hill edifice.

  18. Allan Variance Computed in Space Domain: Definition and Application to InSAR Data to Characterize Noise and Geophysical Signal.

    PubMed

    Cavalié, Olivier; Vernotte, François

    2016-04-01

    The Allan variance was introduced 50 years ago for analyzing the stability of frequency standards. In addition to its metrological interest, it may be also considered as an estimator of the large trends of the power spectral density (PSD) of frequency deviation. For instance, the Allan variance is able to discriminate different types of noise characterized by different power laws in the PSD. The Allan variance was also used in other fields than time and frequency metrology: for more than 20 years, it has been used in accelerometry, geophysics, geodesy, astrophysics, and even finances. However, it seems that up to now, it has been exclusively applied for time series analysis. We propose here to use the Allan variance on spatial data. Interferometric synthetic aperture radar (InSAR) is used in geophysics to image ground displacements in space [over the synthetic aperture radar (SAR) image spatial coverage] and in time thanks to the regular SAR image acquisitions by dedicated satellites. The main limitation of the technique is the atmospheric disturbances that affect the radar signal while traveling from the sensor to the ground and back. In this paper, we propose to use the Allan variance for analyzing spatial data from InSAR measurements. The Allan variance was computed in XY mode as well as in radial mode for detecting different types of behavior for different space-scales, in the same way as the different types of noise versus the integration time in the classical time and frequency application. We found that radial Allan variance is the more appropriate way to have an estimator insensitive to the spatial axis and we applied it on SAR data acquired over eastern Turkey for the period 2003-2011. Spatial Allan variance allowed us to well characterize noise features, classically found in InSAR such as phase decorrelation producing white noise or atmospheric delays, behaving like a random walk signal. We finally applied the spatial Allan variance to an InSAR time

  19. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Valley viticultural area (27 CFR 9.69). From the beginning point, the Rattlesnake Hills viticultural area... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Rattlesnake Hills. 9.193... Rattlesnake Hills. (a) Name. The name of the viticultural area described in this section is “Rattlesnake...

  20. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Valley viticultural area (27 CFR 9.69). From the beginning point, the Rattlesnake Hills viticultural area... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Rattlesnake Hills. 9.193... Rattlesnake Hills. (a) Name. The name of the viticultural area described in this section is “Rattlesnake...

  1. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Valley viticultural area (27 CFR 9.69). From the beginning point, the Rattlesnake Hills viticultural area... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Rattlesnake Hills. 9.193... Rattlesnake Hills. (a) Name. The name of the viticultural area described in this section is “Rattlesnake...

  2. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Chalk Hill. 9.52 Section 9... TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  3. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Chalk Hill. 9.52 Section 9... TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  4. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Chalk Hill. 9.52 Section 9... TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  5. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Chalk Hill. 9.52 Section 9... TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  6. 27 CFR 9.52 - Chalk Hill.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Chalk Hill. 9.52 Section 9... TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.52 Chalk Hill. (a) Name. The name of the viticultural area described in this section is “Chalk Hill.” (b) Approved...

  7. Investigation of Allan variance for determining noise spectral forms with application to microwave radiometry

    NASA Technical Reports Server (NTRS)

    Stanley, William D.

    1994-01-01

    An investigation of the Allan variance method as a possible means for characterizing fluctuations in radiometric noise diodes has been performed. The goal is to separate fluctuation components into white noise, flicker noise, and random-walk noise. The primary means is by discrete-time processing, and the study focused primarily on the digital processes involved. Noise satisfying the requirements was generated by direct convolution, fast Fourier transformation (FFT) processing in the time domain, and FFT processing in the frequency domain. Some of the numerous results obtained are presented along with the programs used in the study.

  8. Allan C. Gotlib, DC, CM: A worthy Member of the Order of Canada

    PubMed Central

    Brown, Douglas M.

    2016-01-01

    On June 29, 2012, His Excellency the Right Honourable David Johnston, Governor General of Canada, announced 70 new appointments to the Order of Canada. Among them was Dr. Allan Gotlib, who was subsequently installed as a Member of the Order of Canada, in recognition of his contributions to advancing research in the chiropractic profession and its inter-professional integration. This paper attempts an objective view of his career, to substantiate the accomplishments that led to Dr. Gotlib receiving Canada’s highest civilian honour. PMID:27069273

  9. Allan C. Gotlib, DC, CM: A worthy Member of the Order of Canada.

    PubMed

    Brown, Douglas M

    2016-03-01

    On June 29, 2012, His Excellency the Right Honourable David Johnston, Governor General of Canada, announced 70 new appointments to the Order of Canada. Among them was Dr. Allan Gotlib, who was subsequently installed as a Member of the Order of Canada, in recognition of his contributions to advancing research in the chiropractic profession and its inter-professional integration. This paper attempts an objective view of his career, to substantiate the accomplishments that led to Dr. Gotlib receiving Canada's highest civilian honour. PMID:27069273

  10. Sea Ice

    NASA Technical Reports Server (NTRS)

    Parkinson, Claire L.; Cavalieri, Donald J.

    2005-01-01

    Sea ice covers vast areas of the polar oceans, with ice extent in the Northern Hemisphere ranging from approximately 7 x 10(exp 6) sq km in September to approximately 15 x 10(exp 6) sq km in March and ice extent in the Southern Hemisphere ranging from approximately 3 x 10(exp 6) sq km in February to approximately 18 x 10(exp 6) sq km in September. These ice covers have major impacts on the atmosphere, oceans, and ecosystems of the polar regions, and so as changes occur in them there are potential widespread consequences. Satellite data reveal considerable interannual variability in both polar sea ice covers, and many studies suggest possible connections between the ice and various oscillations within the climate system, such as the Arctic Oscillation, North Atlantic Oscillation, and Antarctic Oscillation, or Southern Annular Mode. Nonetheless, statistically significant long-term trends are also apparent, including overall trends of decreased ice coverage in the Arctic and increased ice coverage in the Antarctic from late 1978 through the end of 2003, with the Antarctic ice increases following marked decreases in the Antarctic ice during the 1970s. For a detailed picture of the seasonally varying ice cover at the start of the 21st century, this chapter includes ice concentration maps for each month of 2001 for both the Arctic and the Antarctic, as well as an overview of what the satellite record has revealed about the two polar ice covers from the 1970s through 2003.

  11. Rocks of the Columbia Hills

    USGS Publications Warehouse

    Squyres, S. W.; Arvidson, R. E.; Blaney, D.L.; Clark, B. C.; Crumpler, L.; Farrand, W. H.; Gorevan, S.; Herkenhoff, K. E.; Hurowitz, J.; Kusack, A.; McSween, H.Y.; Ming, D. W.; Morris, R.V.; Ruff, S.W.; Wang, A.; Yen, A.

    2006-01-01

    The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic or impact in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in Martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present. Copyright 2006 by the American Geophysical Union.

  12. Cryogenic powderization of Triassic dolostones in the Buda Hills, Hungary

    NASA Astrophysics Data System (ADS)

    Poros, Zsófia; Machel, Hans G.; Mindszenty, Andrea; Molnár, Ferenc

    2013-07-01

    Disintegration of dolostones to dolomite powder (powderization) was a widespread phenomenon in Triassic dolostones of the Buda Hills, where the areal extent of powdered dolostones is large compared to similar occurrences elsewhere in the world. In the Buda Hills, dolostone disintegration proceeded in four stages that correspond to a gradual decrease in particle size, that is, from the parent dolostone to (1) crackle breccia; via (2) mosaic breccia (diameter <2 cm); via (3) mosaic breccia blocks `floating' in dolomite powder; to (4) dolomite powder (diameter 100-300 μm). Stable isotope ratios and trace element compositions of dolomite remained constant throughout these stages, and there are no indications of dissolution in most locations, suggesting that disintegration was predominantly a mechanical process. Combining these findings with the geological history of the region, and supported by a simple freezing/thawing experiment and pertinent experimental studies on weathering of building stones, it appears that powderization in the Buda Hills was caused by repeated freeze-thaw cycles during and/or after the Pleistocene glaciations. Subaerial exposure under cold climate conditions involves multiple freeze-thaw cycles that create mechanical stresses in the rock framework related to the opposing thermal expansion of rock and water that freezes and of ice that liquefies. This process is herewith called `cryogenic powderization'. Our data further suggest that the synergy of four factors promoted dolostone powderization in the Buda Hills: (1) tectonics, which created a pervasive fracture network; (2) intercrystalline porosity of the dolostone; (3) relatively high water saturation; and (4) subaerial exposure under cold climate conditions.

  13. Ancient ice

    NASA Astrophysics Data System (ADS)

    2009-11-01

    Simon Belt, Guillaume Massé and colleagues rammed their way through sheets of ice, spotting some polar bears on the way, in their attempt to reconstruct Arctic sea-ice records covering thousands of years.

  14. Over Ice

    NASA Video Gallery

    All about NASA's IceBridge P-3B plane and its IceBridge retrofit. Upgraded with 21st century "special modifications", the aircraft is less a cold war relic and more like the Space Agency's Millenni...

  15. Onomastic Mirroring: "The Closing of the American Mind" by Allan Bloom and "Lives on the Boundary" by Mike Rose.

    ERIC Educational Resources Information Center

    Heit, Karl

    Although Allan Bloom in "The Closing of the American Mind" and Mike Rose in "Lives on the Boundary" reveal an almost endless list of obvious differences of perspective on literacy and higher education in America, both take divergent yet similar routes to create a permanent place for liberal education. Both Bloom and Rose use the "Gothic Cathedral"…

  16. William Bennett, Allan Bloom, E. D. Hirsch, Jr.: "Great Nature Has Another Thing to Do to You and Me...."

    ERIC Educational Resources Information Center

    Standley, Fred

    1988-01-01

    Examines the views of William Bennett, Allan Bloom, and E. D. Hirsch, Jr. Challenges the relevance of these views in the current milieu, and suggests three more relevant considerations: (1) the myth of the canon; (2) the effects of literary theory; and (3) the effects of the newfound emphasis on rhetoric and composition. (MS)

  17. Avoiding Aliasing in Allan Variance: An Application to Fiber Link Data Analysis.

    PubMed

    Calosso, Claudio E; Clivati, Cecilia; Micalizio, Salvatore

    2016-04-01

    Optical fiber links are known as the most performing tools to transfer ultrastable frequency reference signals. However, these signals are affected by phase noise up to bandwidths of several kilohertz and a careful data processing strategy is required to properly estimate the uncertainty. This aspect is often overlooked and a number of approaches have been proposed to implicitly deal with it. Here, we face this issue in terms of aliasing and show how typical tools of signal analysis can be adapted to the evaluation of optical fiber links performance. In this way, it is possible to use the Allan variance (AVAR) as estimator of stability and there is no need to introduce other estimators. The general rules we derive can be extended to all optical links. As an example, we apply this method to the experimental data we obtained on a 1284-km coherent optical link for frequency dissemination, which we realized in Italy. PMID:26800534

  18. Allan-Herndon-Dudley syndrome and the monocarboxylate transporter 8 (MCT8) gene.

    PubMed

    Schwartz, Charles E; May, Melanie M; Carpenter, Nancy J; Rogers, R Curtis; Martin, Judith; Bialer, Martin G; Ward, Jewell; Sanabria, Javier; Marsa, Silvana; Lewis, James A; Echeverri, Roberto; Lubs, Herbert A; Voeller, Kytja; Simensen, Richard J; Stevenson, Roger E

    2005-07-01

    Allan-Herndon-Dudley syndrome was among the first of the X-linked mental retardation syndromes to be described (in 1944) and among the first to be regionally mapped on the X chromosome (in 1990). Six large families with the syndrome have been identified, and linkage studies have placed the gene locus in Xq13.2. Mutations in the monocarboxylate transporter 8 gene (MCT8) have been found in each of the six families. One essential function of the protein encoded by this gene appears to be the transport of triiodothyronine into neurons. Abnormal transporter function is reflected in elevated free triiodothyronine and lowered free thyroxine levels in the blood. Infancy and childhood in the Allan-Herndon-Dudley syndrome are marked by hypotonia, weakness, reduced muscle mass, and delay of developmental milestones. Facial manifestations are not distinctive, but the face tends to be elongated with bifrontal narrowing, and the ears are often simply formed or cupped. Some patients have myopathic facies. Generalized weakness is manifested by excessive drooling, forward positioning of the head and neck, failure to ambulate independently, or ataxia in those who do ambulate. Speech is dysarthric or absent altogether. Hypotonia gives way in adult life to spasticity. The hands exhibit dystonic and athetoid posturing and fisting. Cognitive development is severely impaired. No major malformations occur, intrauterine growth is not impaired, and head circumference and genital development are usually normal. Behavior tends to be passive, with little evidence of aggressive or disruptive behavior. Although clinical signs of thyroid dysfunction are usually absent in affected males, the disturbances in blood levels of thyroid hormones suggest the possibility of systematic detection through screening of high-risk populations. PMID:15889350

  19. 6. Detail of pilaster cap. Aug. 10, 1936. Joseph Hill, ...

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

    6. Detail of pilaster cap. Aug. 10, 1936. Joseph Hill, photographer, copied from small photo taken by survey member. - Jansonist Colony, Steeple Building, Main & Bishop Hill Streets, Bishop Hill, Henry County, IL

  20. 3. West and south elevations. Joseph Hill, photographer, copied from ...

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

    3. West and south elevations. Joseph Hill, photographer, copied from photo lent by Evelyn S. Craig. August 1936. - Jansonist Colony, Steeple Building, Main & Bishop Hill Streets, Bishop Hill, Henry County, IL

  1. 1. Historic American Buildings Survey Joseph Hill, Photographer August 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer August 1936 FIRST ORIGINAL STORE AND POSTOFFICE, COPY OF AN EARLY PHOTOGRAPH. LENT BY EVELYN S. CRAIG - Jansonist Colony, Colony Store & Post Office, Main & Bishop Hill Streets, Bishop Hill, Henry County, IL

  2. 7. Detail of balcony rail. August 1936. Joseph Hill, photographer, ...

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

    7. Detail of balcony rail. August 1936. Joseph Hill, photographer, copied from small photo taken by survey member. - Jansonist Colony, Steeple Building, Main & Bishop Hill Streets, Bishop Hill, Henry County, IL

  3. Report on the Black Hills Alliance.

    ERIC Educational Resources Information Center

    Ryan, Joe

    1979-01-01

    A rally to save the Black Hills from coal- and uranium-greedy energy companies was held on July 6 and over 2,000 joined in a 15-mile walk on July 7 in Rapid City, South Dakota. The Black Hills Alliance, an Indian coalition concerned about energy development proposals in the Great Plains, sponsored the gathering. (NQ)

  4. Colleges as Shining Cities on a Hill

    ERIC Educational Resources Information Center

    Townsend, Kathleen Kennedy

    2012-01-01

    In this article, the author proposes that the notion of America be reintroduced as the "shining city on a hill," that abiding image from American history. The image of the shining city on a hill captures the imagination because it reflects the abiding truth that people become fully human in society, not outside of it. People need one another to…

  5. Glaciated appalachian plateau: till shadows on hills.

    PubMed

    Coates, D R

    1966-06-17

    North slopes are twice as steep as south slopes on the hills of central New York. This asymmetry is caused by unequal till thickness-3.6 meters on north slopes and 27.6 meters on south slopes. Previous workers interpreted the hills as being of bedrock sculptured by glacial erosion, with till 0.9 to 3 meters thick. PMID:17755398

  6. Counseling Uses of the Hill Interaction Matrix.

    ERIC Educational Resources Information Center

    Boyd, Robert E.

    While the Hill Interaction Matrix was developed as a research instrument to assess interview process, it is also generally useful in any undertaking requiring the evaluation of verbal interaction and, hence, can be used as an aid in modifying communication in order to increase its therapeutic effect. The Hill Interaction Matrix with accompanying…

  7. Sea Ice

    NASA Technical Reports Server (NTRS)

    Perovich, D.; Gerland, S.; Hendricks, S.; Meier, Walter N.; Nicolaus, M.; Richter-Menge, J.; Tschudi, M.

    2013-01-01

    During 2013, Arctic sea ice extent remained well below normal, but the September 2013 minimum extent was substantially higher than the record-breaking minimum in 2012. Nonetheless, the minimum was still much lower than normal and the long-term trend Arctic September extent is -13.7 per decade relative to the 1981-2010 average. The less extreme conditions this year compared to 2012 were due to cooler temperatures and wind patterns that favored retention of ice through the summer. Sea ice thickness and volume remained near record-low levels, though indications are of slightly thicker ice compared to the record low of 2012.

  8. Sea ice terminology

    SciTech Connect

    Not Available

    1980-09-01

    A group of definitions of terms related to sea ice is presented, as well as a graphic representation of late winter ice zonation of the Beaufort Sea Coast. Terms included in the definition list are belt, bergy bit, bight, brash ice, calving, close pack ice, compacting, compact pack ice, concentration, consolidated pack ice, crack, diffuse ice edge, fast ice, fast-ice boundary, fast-ice edge, first-year ice, flaw, flaw lead, floe, flooded ice, fractured, fractured zone, fracturing, glacier, grey ice, grey-white ice, growler, hummock, iceberg, iceberg tongue, ice blink, ice boundary, ice cake, ice edge, ice foot, ice free, ice island, ice shelf, large fracture, lead, medium fracture, multiyear ice, nilas, old ice, open pack ice, open water, pack ice, polar ice, polynya, puddle, rafted ice, rafting, ram, ridge, rotten ice, second-year ice, shearing, shore lead, shore polynya, small fracture, strip, tabular berg, thaw holes, very close pack ice, very open pack ice, water sky, young coastal ice, and young ice.

  9. Solar Rossby Wave 'Hills' Identified As Supergranules

    NASA Technical Reports Server (NTRS)

    Williams, P. E.; Hathaway, David H.; Cuntz, M.

    2007-01-01

    We explore the nature of 'hills' observed on the solar surface which had previously been attributed to Rossby waves. We investigate the sol ar hills phenomenon by analyzing the output from a synthetic model ba sed solely on the observed solar photospheric convection spectrum. We show that the characteristics of these hills can be explained by the corrugation of the surface produced by the radial flows of the conve ction. The hills in our simulations are dominated by supergranules, a well-known component of solar convection. Rossby waves have been predicted to exist within the Sun and may play an important role in the d ynamics of the solar interior, including the Sun's differential rotat ion and magnetic dynamo. Our study suggests, however, that the hills observed at the solar limb do not confirm the existence of solar Ross by waves.

  10. Layered Rocks in 'Columbia Hills'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This black-and-white image shows the first layered rocks scientists have seen close up in Gusev Crater, where NASA's Mars Exploration Rover Spirit landed Jan. 4, 2004. While Spirit's twin rover, Opportunity, reached the stadium-size Endurance Crater on the other side of Mars and began exploring its many layered outcrops in early May, Spirit traveled more than 3.5 kilometers (2.2 miles) to get to this layered bedrock in the 'Columbia Hills.' Scientists are planning to conduct a study of these rocks to determine if they are volcanic or sedimentary in origin, and if they have been chemically altered. Spirit's panoramic camera took this image on sol 217 (Aug. 13, 2004).

  11. Psychrophilic pseudomonas in antarctic freshwater lake at stornes peninsula, larsemann hills over east Antarctica.

    PubMed

    Chauhan, Abhishek; Bharti, Pawan K; Goyal, Pankaj; Varma, Ajit; Jindal, Tanu

    2015-01-01

    The Larsemann Hills is an ice-free area of approximately 50 km(2), located halfway between the Vestfold Hills and the Amery Ice Shelf on the south-eastern coast of Prydz Bay, Princess Elizabeth Land, East Antarctica (69º30'S, 76º19'58″E). The ice-free area consists of two major peninsulas (Stornes and Broknes), four minor peninsulas, and approximately 130 islands. The Larsemann Hills area contains more than 150 lakes at different Islands and Peninsulas. Nine lake water samples were collected in a gamma sterilized bottles and were kept in an ice pack to prevent any changes in the microbial flora of the samples during the transportation. The water samples were transported to the lab in vertical position maintaining the temperature 1-4 °C with ice pack enveloped conditions. Samples were studied for Psychrophilic bacterial count, Pseudomonas spp., Staphylococcus aureus, Salmonella and Total MPN Coliform per 100 ml. Psychrophillic counts were found in the range of 12 cfu to 1.6 × 10(2) cfu in all the samples. MPN Coliform per 100 ml was found to be absent in all the samples. No growth and characteristics colonies observed when tested for Salmonella and S.aureus. Pseudomonas sp. was found in ST-2 lake water sample as characteristics colonies (Optimum Growth) were observed on selective media at 22 and 25 °C. Further several biochemical tests were also performed to confirm the presence of this Potential Psychrophilic Pseudomonas sp. for its further application in Science and Technology. PMID:26543717

  12. Late-glacial and postglacial history of the hill'', Norwich University campus, Northfield, Vermont

    SciTech Connect

    Larsen, F.D. . Dept. of Geology)

    1993-03-01

    The central part of the Norwich University campus at Northfield is built on a kame about 60 ft high on the side of the Dog River valley. Significant excavations made between 1979 and 1991 in the flank of the hill provide details about its glacial origin. Collapsed ice-contact lake deposits on the northwestern flank of the kame are overlain by undisturbed lake sediments formed by turbidity currents that moved southward in glacial Lake Roxbury. Lake Roxbury formed when the retreating ice margin blocked the north-draining Dog River valley and caused melt water to drain south over a 1,010-foot threshold at Roxbury. The lowest deposits exposed on the southeast flank of the kame are highly deformed and include a chaotic slide breccia overlain by progressively less deformed lake-bottom sediments. Northward retreat of the ice margin permitted Lake Roxbury to drop 80 ft to the level of glacial Lake Winooski, which still left 80 ft of lake water over the top of the hill''. Following the lowering of Lake Winooski, stream terraces were cut on the west flank of the hill''. The terraces are underlain by imbricated pebble gravel deposited by the north-flowing Dog River that probably was graded to a lower glacial lake in the Winooski River valley to the north. Downcutting by the Dog River and subsequent lateral migration of its meanders produced the topography the authors see today. The late-glacial and postglacial history can be summarized as follows: (1) deposition of lake sediments in contact with buried ice, (2) collapse and continued deposition of lake sediments during melting of buried ice, (3) deposition of undeformed lake sediments, (4) drainage of glacial lakes, and (5) development of stream terraces and the modern flood plain.

  13. Allan Hills 84025 - The second brachinite, far more differentiated than brachina, and an ultramafic achondritic clast from L chondrite Yamato 75097

    NASA Technical Reports Server (NTRS)

    Warren, P. H.; Kallemeyn, G. W.

    1989-01-01

    New bulk-compositional and petrographic data tend to confirm that dunitic-wehrlitic meteorite ALH84025 is a second brachinite. It is suggested here that ALH84025 originated as an olivine heteradcumulate, whereas Brachina, or ALH84025, originated as an olivine orthocumulate. The tendency for pyroxenes among brachinites to be high-Ca may be a consequence of a relatively low MgO/FeO ratio, and/or high Na/Ca and K/Ca ratios in the bulk parent body. New data for a 2.5-cm dunite-melatroctolite clast from L6 chondrite Y75097 are reported. This clast has experience depletion of middle REE, except for a large (+) Eu anomaly. The clast as a whole is enriched in phosphates, but almost exclusively in its least-metamorphosed 'core' portion, whereas the analyzed samples represent phosphate-poor portions. It is suggested that this bizarre assemblage probably originated as an achondrite containing cumulus olivine, plagioclase, and phosphate, not necessarily all from a single igneous source rock.

  14. Ice detector

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M. (Inventor)

    1988-01-01

    An ice detector is provided for the determination of the thickness of ice on the outer surface on an object (e.g., aircraft) independently of temperature or the composition of the ice. First capacitive gauge, second capacitive gauge, and temperature gauge are embedded in embedding material located within a hollowed out portion of the outer surface. This embedding material is flush with the outer surface to prevent undesirable drag. The first capacitive gauge, second capacitive gauge, and the temperature gauge are respectively connected to first capacitive measuring circuit, second capacitive measuring circuit, and temperature measuring circuit. The geometry of the first and second capacitive gauges is such that the ratio of the voltage outputs of the first and second capacitance measuring circuits is proportional to the thickness of ice, regardless of ice temperature or composition. This ratio is determined by offset and dividing circuit.

  15. Descent from the Summit of 'Husband Hill'

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for Descent from the Summit of 'Husband Hill' (QTVR)

    In late November 2005 while descending 'Husband Hill,' NASA's Mars Exploration Rover Spirit took the most detailed panorama so far of the 'Inner Basin,' the rover's next target destination. Spirit acquired the 405 individual images that make up this 360-degree view of the surrounding terrain using five different filters on the panoramic camera. The rover took the images on Martian days, or sols, 672 to 677 (Nov. 23 to 28, 2005 -- the Thanksgiving holiday weekend).

    This image is an approximately true-color rendering using camera's 750-, 530-, and 430-nanometer filters. Seams between individual frames have been eliminated from the sky portion of the mosaic to better simulate the vista a person standing on Mars would see.

    'Home Plate,' a bright, semi-circular feature scientists hope to investigate, is harder to discern in this image than in earlier views taken from higher up the hill. Spirit acquired this more oblique view, known as the 'Seminole panorama,' from about halfway down the south flank of Husband Hill, 50 meters (164 feet) or so below the summit. Near the center of the panorama, on the horizon, are 'McCool Hill' and 'Ramon Hill,' named, like Husband Hill, in honor of the fallen astronauts of the space shuttle Columbia. Husband Hill is visible behind the rover, on the right and left sides of the panorama. An arc of rover tracks made while avoiding obstacles and getting into position to examine rock outcrops can be traced over a long distance by zooming in to explore the panorama in greater detail.

    Spirit is now significantly farther downhill toward the center of this panorama, en route to Home Plate and other enigmatic soils and outcrop rocks in the quest to uncover the history of Gusev Crater and the 'Columbia Hills.'

  16. Cryoconite and Ice-bubble Microbial Ecosystems in Antarctica

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    During the Antarctica 2000 Expedition samples of rocks and ice bubbles entrained in ice were collected from the blue ice fields near the Moulton Escarpment of the Thiel Mountains (85S, 94W) and the Morris Moraine of the Patriot Hills (80S, 8 1 W) Ellsworth Mountains of Antarctica. Investigation of the microbiota of these cryoconite and ice bubble ecosystems are now being conducted to help refine chemical and morphological biomarkers of potential significance to Astrobiology. The Antarctica 2000 Expedition will be discussed and the preliminary results of the studies of the ice bubble and cryoconite microbial ecosystems discussed. Recent ESEM images of the Antarctic microbiota will be presented a the relevance of ice ecosystems to Astrobiology will be discussed.

  17. A SYMPLECTIC INTEGRATOR FOR HILL'S EQUATIONS

    SciTech Connect

    Quinn, Thomas; Barnes, Rory; Perrine, Randall P.; Richardson, Derek C.

    2010-02-15

    Hill's equations are an approximation that is useful in a number of areas of astrophysics including planetary rings and planetesimal disks. We derive a symplectic method for integrating Hill's equations based on a generalized leapfrog. This method is implemented in the parallel N-body code, PKDGRAV, and tested on some simple orbits. The method demonstrates a lack of secular changes in orbital elements, making it a very useful technique for integrating Hill's equations over many dynamical times. Furthermore, the method allows for efficient collision searching using linear extrapolation of particle positions.

  18. Hill-Climbing Attacks and Robust Online Signature Verification Algorithm against Hill-Climbing Attacks

    NASA Astrophysics Data System (ADS)

    Muramatsu, Daigo

    Attacks using hill-climbing methods have been reported as a vulnerability of biometric authentication systems. In this paper, we propose a robust online signature verification algorithm against such attacks. Specifically, the attack considered in this paper is a hill-climbing forged data attack. Artificial forgeries are generated offline by using the hill-climbing method, and the forgeries are input to a target system to be attacked. In this paper, we analyze the menace of hill-climbing forged data attacks using six types of hill-climbing forged data and propose a robust algorithm by incorporating the hill-climbing method into an online signature verification algorithm. Experiments to evaluate the proposed system were performed using a public online signature database. The proposed algorithm showed improved performance against this kind of attack.

  19. Inside Beacon Hill: Bertrand Russell as Schoolmaster.

    ERIC Educational Resources Information Center

    Jespersen, Shirley

    1987-01-01

    The author describes the life and theories of Bertrand Russell, founder of Beacon Hill School. Russell's educational theories centered on the personal autonomy of the student and democratization of the learning process. (CH)

  20. Exploring Hill Ciphers with Graphing Calculators.

    ERIC Educational Resources Information Center

    St. John, Dennis

    1998-01-01

    Explains how to code and decode messages using Hill ciphers which combine matrix multiplication and modular arithmetic. Discusses how a graphing calculator can facilitate the matrix and modular arithmetic used in the coding and decoding procedures. (ASK)

  1. The Igwisi Hills extrusive 'kimberlites'

    NASA Technical Reports Server (NTRS)

    Reid, A. M.; Donaldson, C. H.; Dawson, J. B.; Brown, R. W.; Ridley, W. I.

    1975-01-01

    The petrography and mineral chemistry of volcanic rocks from the Igwisi Hills in Tanzania are discussed. There is considerable evidence to suggest that the Igwisi rocks are extrusive kimberlites: a two-component nature with high P-T minerals in a low P-T matrix; the presence of chrome pyrope, Al enstatite, chrome diopside, chromite and olivine; a highly oxidized, volatile-rich matrix with serpentine, calcite, magnetite, perovskite; high Sr, Zr, and Nb contents; occurrence in a narrow isolated vent within a stable shield area. The Igwisi rocks differ from kimberlite in the lack of magnesian ilmenite, the scarcity of matrix phlogopite, and the overall low alkali content. They apparently contain material from phlogopite-bearing garnet peridotites with a primary mineral assemblage indicative of equilibrium at upper mantle temperatures and pressures. This primary assemblage was brought rapidly to the surface in a gas-charged, carbonate-rich fluid. Rapid upward transport, extrusion, and rapid cooling have tended to prevent reaction between inclusions and the carbonate-rich matrix that might otherwise have yielded a more typical kimberlite.

  2. Oblique View of Columbia Hills

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Annotated Version

    This perspective view looking toward the northeast shows part of the Columbia Hills range inside Gusev Crater. At the center is the winter campaign site of NASA's Mars Exploration Rover Spirit.

    On its 805th Martian day, or sol, (April 8, 2006), Spirit was parked on a slope tilting 11 degrees to the north to maximize sunlight on the solar panels during the southern winter season. Science observations were formulated to take advantage of the long time during which the rover was parked. The plan focused on two tasks: tracking atmospheric and surface dynamics by periodically surveying the surface and atmosphere; and extensively examining surrounding terrains, rocks and soils using the panoramic camera and the miniature thermal emission spectrometer, coupled with long duration measurements using the alpha particle X-ray and Moessbauer spectrometers of rock and soil targets. For reference, the feature known as 'Home Plate' is approximately 90 meters (295 feet) wide.

    An image from Mars Global Surveyor's Mars Orbital Camera, catalogued as E03_00012 and courtesy Malin Space Science Systems, was used as the base image for this figure. The perspective was generated using elevation data generated from analyses of the camera's stereo images by the U.S. Geological Survey, Flagstaff, Ariz.

  3. Soufriere Hills, Montserrat, West Indies

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Volcanic activity on the West Indian island of Montserrat has remained high for several years-the current activity started in 1995. However, remote sensing of the island has been difficult because of frequent cloud cover. The International Space Station crew flew north of the island on a clear day in early July (July 9, 2001) and recorded a vigorous steam plume emanating from the summit of Soufriere Hills. The image also reveals the extensive volcanic mud flows (lahars) and new deltas built out from the coast from the large amounts of volcanic debris delivered downstream by the rivers draining the mountain. As a small island (only 13 x 8 km), all of Montserrat has been impacted by the eruptions. Sources of Information: Smithsonian Global Volcanism Program Italy's Volcanoes Montserrat Volcano Observatory Digital photograph number ISS002-E-9309 was taken on 9 July 2001 from Space Station Alpha and was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

  4. Application of the Allan Variance to Time Series Analysis in Astrometry and Geodesy: A Review.

    PubMed

    Malkin, Zinovy

    2016-04-01

    The Allan variance (AVAR) was introduced 50 years ago as a statistical tool for assessing the frequency standards deviations. For the past decades, AVAR has increasingly been used in geodesy and astrometry to assess the noise characteristics in geodetic and astrometric time series. A specific feature of astrometric and geodetic measurements, as compared with clock measurements, is that they are generally associated with uncertainties; thus, an appropriate weighting should be applied during data analysis. In addition, some physically connected scalar time series naturally form series of multidimensional vectors. For example, three station coordinates time series X, Y, and Z can be combined to analyze 3-D station position variations. The classical AVAR is not intended for processing unevenly weighted and/or multidimensional data. Therefore, AVAR modifications, namely weighted AVAR (WAVAR), multidimensional AVAR (MAVAR), and weighted multidimensional AVAR (WMAVAR), were introduced to overcome these deficiencies. In this paper, a brief review is given of the experience of using AVAR and its modifications in processing astrogeodetic time series. PMID:26540681

  5. Twenty-Five Years of Applications of the Modified Allan Variance in Telecommunications.

    PubMed

    Bregni, Stefano

    2016-04-01

    The Modified Allan Variance (MAVAR) was originally defined in 1981 for measuring frequency stability in precision oscillators. Due to its outstanding accuracy in discriminating power-law noise, it attracted significant interest among telecommunications engineers since the early 1990s, when it was approved as a standard measure in international standards, redressed as Time Variance (TVAR), for specifying the time stability of network synchronization signals and of equipment clocks. A dozen years later, the usage of MAVAR was also introduced for Internet traffic analysis to estimate self-similarity and long-range dependence. Further, in this field, it demonstrated superior accuracy and sensitivity, better than most popular tools already in use. This paper surveys the last 25 years of progress in extending the field of application of the MAVAR in telecommunications. First, the rationale and principles of the MAVAR are briefly summarized. Its adaptation as TVAR for specification of timing stability is presented. The usage of MAVAR/TVAR in telecommunications standards is reviewed. Examples of measurements on real telecommunications equipment clocks are presented, providing an overview on their actual performance in terms of MAVAR. Moreover, applications of MAVAR to network traffic analysis are surveyed. The superior accuracy of MAVAR in estimating long-range dependence is emphasized by highlighting some remarkable practical examples of real network traffic analysis. PMID:26529754

  6. Observation, Inference, and Imagination: Elements of Edgar Allan Poe's Philosophy of Science

    NASA Astrophysics Data System (ADS)

    Gelfert, Axel

    2014-03-01

    Edgar Allan Poe's standing as a literary figure, who drew on (and sometimes dabbled in) the scientific debates of his time, makes him an intriguing character for any exploration of the historical interrelationship between science, literature and philosophy. His sprawling `prose-poem' Eureka (1848), in particular, has sometimes been scrutinized for anticipations of later scientific developments. By contrast, the present paper argues that it should be understood as a contribution to the raging debates about scientific methodology at the time. This methodological interest, which is echoed in Poe's `tales of ratiocination', gives rise to a proposed new mode of—broadly abductive—inference, which Poe attributes to the hybrid figure of the `poet-mathematician'. Without creative imagination and intuition, Science would necessarily remain incomplete, even by its own standards. This concern with imaginative (abductive) inference ties in nicely with his coherentism, which grants pride of place to the twin virtues of Simplicity and Consistency, which must constrain imagination lest it degenerate into mere fancy.

  7. THE DEAD-LIVING-MOTHER: MARIE BONAPARTE'S INTERPRETATION OF EDGAR ALLAN POE'S SHORT STORIES.

    PubMed

    Obaid, Francisco Pizarro

    2016-06-01

    Princess Marie Bonaparte is an important figure in the history of psychoanalysis, remembered for her crucial role in arranging Freud's escape to safety in London from Nazi Vienna, in 1938. This paper connects us to Bonaparte's work on Poe's short stories. Founded on concepts of Freudian theory and an exhaustive review of the biographical facts, Marie Bonaparte concluded that the works of Edgar Allan Poe drew their most powerful inspirational force from the psychological consequences of the early death of the poet's mother. In Bonaparte's approach, which was powerfully influenced by her recognition of the impact of the death of her own mother when she was born-an understanding she gained in her analysis with Freud-the thesis of the dead-living-mother achieved the status of a paradigmatic key to analyze and understand Poe's literary legacy. This paper explores the background and support of this hypothesis and reviews Bonaparte's interpretation of Poe's most notable short stories, in which extraordinary female figures feature in the narrative. PMID:27194275

  8. Drought in the Black Hills

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Annotated Color-Coded Map

    Despite good rainfall and record-setting snowstorms in the spring of 2005, most of northeastern Wyoming, the Black Hills, and western South Dakota remain in the midst of a severe drought. This set of images and maps from NASA's Multi-angle Imaging SpectroRadiometer (MISR) contrast the appearance of the Black Hills region of northwestern South Dakota on July 12, 2000 (left column), with views acquired four years later, on July 14, 2004 (right column). The natural-color images along the top are from MISR's nadir (downward-looking) camera. The browning that appears in 2004 compared with 2000 indicates that the vigor of green vegetation was significantly diminished in 2004.

    The color-coded maps (along the bottom) provide a quantitative measurement of the sunlight reflected from these surfaces, and the loss of sunlight-absorbing vegetation between the 2000 and 2004 dates. As the vegetation faded with the drought, the albedo at the surface increased. Albedo measures the fraction of incident sunlight that is reflected by a surface, and can vary between zero (if all the incident sunlight is absorbed and none is reflected) and one (if all sunlight is reflected and none is absorbed). Dense forest has a low albedo; bright desert, snow and clouds, have a high albedo. Here, albedo is provided for the wavelengths of sunlight that plants use for photosynthesis (400 - 700 nanometers). This measurement is known as the albedo for Photosynthetically Active Radiation (PAR). Surfaces with greater absorption of PAR appear here in blue hues, whereas surfaces with lower absorption appear as green, yellow, orange or red. Black pixels indicate areas where albedo could not be derived, usually due to the presence of clouds. In July 2004, low albedo areas (blue pixels) are notably reduced in extent, and higher albedo areas (yellow, orange and red pixels) have increased.

    Because incoming sunlight is

  9. Bunker Hill Sediment Characterization Study

    SciTech Connect

    Neal A. Yancey; Debby F. Bruhn

    2009-12-01

    The long history of mineral extraction in the Coeur d’Alene Basin has left a legacy of heavy metal laden mine tailings that have accumulated along the Coeur d’Alene River and its tributaries (U.S. Environmental Protection Agency, 2001; Barton, 2002). Silver, lead and zinc were the primary metals of economic interest in the area, but the ores contained other elements that have become environmental hazards including zinc, cadmium, lead, arsenic, nickel, and copper. The metals have contaminated the water and sediments of Lake Coeur d’Alene, and continue to be transported downstream to Spokane Washington via the Spokane River. In 1983, the EPA listed the Bunker Hill Mining and Metallurgical Complex on the National Priorities List. Since that time, many of the most contaminated areas have been stabilized or isolated, however metal contaminants continue to migrate through the basin. Designation as a Superfund site causes significant problems for the economically depressed communities in the area. Identification of primary sources of contamination can help set priorities for cleanup and cleanup options, which can include source removal, water treatment or no action depending on knowledge about the mobility of contaminants relative to water flow. The mobility of contaminant mobility under natural or engineered conditions depends on multiple factors including the physical and chemical state (or speciation) of metals and the range of processes, some of which can be seasonal, that cause mobilization of metals. As a result, it is particularly important to understand metal speciation (National Research Council, 2005) and the link between speciation and the rates of metal migration and the impact of natural or engineered variations in flow, biological activity or water chemistry.

  10. Operation IceBridge: Sea Ice Interlude

    NASA Video Gallery

    Sea ice comes in an array of shapes and sizes and has its own ephemeral beauty. Operation IceBridge studies sea ice at both poles, and also runs across interesting formations en route to other targ...

  11. Breakup of Pack Ice, Antarctic Ice Shelf

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Breakup of Pack Ice along the periphery of the Antarctic Ice Shelf (53.5S, 3.0E) produced this mosaic of ice floes off the Antarctic Ice Shelf. Strong offshore winds, probably associated with strong katabatic downdrafts from the interior of the continent, are seen peeling off the edges of the ice shelf into long filamets of sea ice, icebergs, bergy bits and growlers to flow northward into the South Atlantic Ocean. 53.5S, 3.0E

  12. Bursting money bins, the ice and water structure

    NASA Astrophysics Data System (ADS)

    Bagnoli, Franco

    2015-05-01

    In the classic comics by Carl Barks, "The Big Bin on Killmotor Hill" [1], Uncle Scrooge, trying to defend his money bin from the Beagle Boys, follows a suggestion by Donald Duck, and fills the bin with water. Unfortunately, that night is going be the coldest one in the history of Ducksburg. The water freezes, bursting the "ten-foot walls'' of the money bin, and finally the gigantic cube of ice and dollars slips down the hill up to the Beagle Boys lot.

  13. Mutations in MCT8 in patients with Allan-Herndon-Dudley-syndrome affecting its cellular distribution.

    PubMed

    Kersseboom, Simone; Kremers, Gert-Jan; Friesema, Edith C H; Visser, W Edward; Klootwijk, Wim; Peeters, Robin P; Visser, Theo J

    2013-05-01

    Monocarboxylate transporter 8 (MCT8) is a thyroid hormone (TH)-specific transporter. Mutations in the MCT8 gene are associated with Allan-Herndon-Dudley Syndrome (AHDS), consisting of severe psychomotor retardation and disturbed TH parameters. To study the functional consequences of different MCT8 mutations in detail, we combined functional analysis in different cell types with live-cell imaging of the cellular distribution of seven mutations that we identified in patients with AHDS. We used two cell models to study the mutations in vitro: 1) transiently transfected COS1 and JEG3 cells, and 2) stably transfected Flp-in 293 cells expressing a MCT8-cyan fluorescent protein construct. All seven mutants were expressed at the protein level and showed a defect in T3 and T4 transport in uptake and metabolism studies. Three mutants (G282C, P537L, and G558D) had residual uptake activity in Flp-in 293 and COS1 cells, but not in JEG3 cells. Four mutants (G221R, P321L, D453V, P537L) were expressed at the plasma membrane. The mobility in the plasma membrane of P537L was similar to WT, but the mobility of P321L was altered. The other mutants studied (insV236, G282C, G558D) were predominantly localized in the endoplasmic reticulum. In essence, loss of function by MCT8 mutations can be divided in two groups: mutations that result in partial or complete loss of transport activity (G221R, P321L, D453V, P537L) and mutations that mainly disturb protein expression and trafficking (insV236, G282C, G558D). The cell type-dependent results suggest that MCT8 mutations in AHDS patients may have tissue-specific effects on TH transport probably caused by tissue-specific expression of yet unknown MCT8-interacting proteins. PMID:23550058

  14. The Geomorphic Footprint of Ice Streaming in the Newfoundland Ice Cap Mapped from Remotely Sensed Data

    NASA Astrophysics Data System (ADS)

    Blundon, Phillip

    Although ice streams have long been proposed within the Newfoundland Ice Cap, this work confirms, for the first time, ice stream operation within terrestrial areas. Through the application of a multi-scale mapping approach several ice stream footprints were identified and characterized. These footprints are characterized by convergence of elongated flow-parallel landforms including drumlins, mega flutes, and crag-and-tail hills. Detailed investigation of the Exploits Ice Stream showed that variations in landform morphology mimic predicted velocity fields within ice steams. All flow sets are characterized by generally thin sediment cover and typically display some form of topographic control, suggesting that topography was more important in controlling ice stream location than the presence of a soft deformable bed. Investigation of landform mapping procedures using Shuttle Radar Topography Mission (SRTM) digital elevation models and aerial photographs, shows that while not as detailed, mapping from SRTM DEMs was able to produce landform maps showing trends similar to those identified on aerial photographs, highlighting their use in reconnaissance level landform mapping.

  15. Matching, maximizing, and hill-climbing

    PubMed Central

    Hinson, John M.; Staddon, J. E. R.

    1983-01-01

    In simple situations, animals consistently choose the better of two alternatives. On concurrent variable-interval variable-interval and variable-interval variable-ratio schedules, they approximately match aggregate choice and reinforcement ratios. The matching law attempts to explain the latter result but does not address the former. Hill-climbing rules such as momentary maximizing can account for both. We show that momentary maximizing constrains molar choice to approximate matching; that molar choice covaries with pigeons' momentary-maximizing estimate; and that the “generalized matching law” follows from almost any hill-climbing rule. PMID:16812350

  16. Ruemker Hills - A lunar volcanic dome complex

    NASA Technical Reports Server (NTRS)

    Smith, E. I.

    1974-01-01

    The Ruemker Hills, a volcanic dome-flow complex in the northern Oceanus Procellarum, is characterized by overlapping plains-forming units with lobate scarps, volcanic domes, a 60-km ring, and a scarp which separates the plateau from surrounding mare materials. Plains-forming units are interpreted as fluid volcanic flows, and domes as viscous extrusions. One dome may be a stratovolcano. The ring system is discordant with regional structural trends and probably has a local origin. The Ruemker Hills is the closest lunar analog to the large Martian shield structures revealed on the Mariner 9 photographs of Mars.

  17. OVERVIEW OF GOLD HILL MILL, ROAD, AND WARM SPRINGS CAMP ...

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

    OVERVIEW OF GOLD HILL MILL, ROAD, AND WARM SPRINGS CAMP BUILDINGS, LOOKING SOUTH SOUTHEAST. THE FUNCTION OF THE FLAT AREA AT CENTER RIGHT IS UNKNOWN. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  18. Hill-Burton Free and Reduced Cost Health Care

    MedlinePlus

    ... Hill-Burton Spanish Brochure (PDF - 83 KB) HHS Poverty Guidelines HHS Spanish Poverty Guidelines (PDF - 32 KB) Spanish Inquiry Letter (PDF - ... income is at or below the current HHS Poverty Guidelines . You may be eligible for Hill-Burton ...

  19. 3. GENERAL VIEW DOWN EAST HILLS DRIVE, BUILDING 20 (ONE ...

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

    3. GENERAL VIEW DOWN EAST HILLS DRIVE, BUILDING 20 (ONE BEDROOM) AND BUILDING 21 (TWO/THREE BEDROOM); ACTIVITY CENTER IN REAR, FACING NORTHEAST. - Aluminum City Terrace, East Hill Drive, New Kensington, Westmoreland County, PA

  20. 1. HISTORIC PHOTOGRAPH, VIEW OF ROUND HILL ROAD BRIDGE, LOOKING ...

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

    1. HISTORIC PHOTOGRAPH, VIEW OF ROUND HILL ROAD BRIDGE, LOOKING WEST, CA. 1940. CONNECTICUT DEPARTMENT OF TRANSPORTATION. - Merritt Parkway, Round Hill Road Bridge, Spanning Merritt Parkway at 3.5 mile mark, Greenwich, Fairfield County, CT

  1. The hill forts and castle mounds in Lithuania: interaction between geodiversity and human-shaped landscape

    NASA Astrophysics Data System (ADS)

    Skridlaite, Grazina; Guobyte, Rimante; Satkunas, Jonas

    2015-04-01

    Lithuania is famous for its abundant, picturesque hill forts and castle mounds of natural origin. In Lithuania as well as in whole Europe the fortified hills were used as the society dwelling place since the beginning of the Late Bronze Age. Their importance increased when Livonian and Teutonic Orders directed a series of military campaigns against Lithuania with the aim of expansion of Christianity in the region at the end of 1st millennium AD, and they were intensively used till the beginning of the 15th c. when most of them were burned down during fights with the Orders or just abandoned due to the changing political and economical situation. What types of the geodiversity were used for fortified dwellings? The choice in a particular area depended on a variety of geomorphology left behind the retreating ice sheets. High spots dominating their surroundings were of prime interest. In E and SE Lithuania, the Baltic Upland hills marking the eastern margin of the last Weichselian glacier hosted numerous fortified settlements from the end of 2nd millennium BC to the Medieval Ages (Narkunai, Velikuskes etc). In W Lithuania, plateau-like hills of the insular Samogitian Upland had been repeatedly fortified from the beginning of 1st millennium AD to the 14th century (Satrija, Medvegalis etc). Chains of hill forts and castle mounds feature the slopes of glaciofluvial valleys of Nemunas, Neris and other rivers where the slopes were dissected by affluent rivulets and ravines and transformed into isolated, well protected hills (Kernave, Punia, Veliuona etc). Peninsulas and headlands formed by the erosion of fluvial and lacustrine deposits were used in the lowlands, e.g. in central and N Lithuania (Paberze, Mezotne etc). How much the landscape was modified for defense purposes? Long-term erosion and overgrowing vegetation damaged the former fortified sites, however some remains and the archeological excavations allowed their reconstruction. The fortified Bronze Age settlements

  2. Reading Probe Will Continue on Capitol Hill

    ERIC Educational Resources Information Center

    Manzo, Kathleen Kennedy

    2007-01-01

    The recent wrap-up of an intensive, two-year examination of the federal Reading First initiative is not expected to halt debate over the program. Given the broad agreement in seven federal reports that serious problems occurred in the oversight of the program's implementation, the findings have sparked interest on Capitol Hill, as lawmakers…

  3. McGraw-Hill Authoring System.

    ERIC Educational Resources Information Center

    Bruce, A. Wayne

    1984-01-01

    Reviews the McGraw-Hill Interactive Authoring System which allows authors to create computer-based courses with or without interactive video. Use of the program requires no programming skills and authors do not need to learn a special language. The system's operation, performance, ease of use, documentation, and management are considered. (JN)

  4. ENHANCED REMEDIATION DEMONSTRATIONS AT HILL AFB: INTRODUCTION

    EPA Science Inventory

    Nine enhanced aquifer remediation technologies were demonstrated side-by-side at a Hill Air Force Base Chemical Disposal Pit/Fire Training Area site. The demonstrations were performed inside 3 x 5 m cells isolated from the surrounding shallow aquifer by steel piling. The site w...

  5. General Education at UNC-Chapel Hill

    ERIC Educational Resources Information Center

    Schalin, Jay; Robinson, Jenna Ashley

    2013-01-01

    The general education program at UNC-Chapel Hill has abandoned the concept of a core curriculum. Instead, students choose their "required" classes from lists of thousands of courses that may be as narrow and idiosyncratic as Love, Sex and Marriage in Soviet Culture (RUSS 277) or The Gardens, Shrines and Temples of Japan (ASIA 586).…

  6. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Valley viticultural area (27 CFR 9.69). From the beginning point, the Rattlesnake Hills viticultural area boundary line— (2) Proceeds straight eastward, crossing onto the Elephant Mountain map, to the 2,192-foot...) Yakima East Quadrangle, Washington—Yakima Co., 1953, photorevised 1985; (2) Elephant Mountain...

  7. 27 CFR 9.193 - Rattlesnake Hills.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Valley viticultural area (27 CFR 9.69). From the beginning point, the Rattlesnake Hills viticultural area boundary line— (2) Proceeds straight eastward, crossing onto the Elephant Mountain map, to the 2,192-foot...) Yakima East Quadrangle, Washington—Yakima Co., 1953, photorevised 1985; (2) Elephant Mountain...

  8. The House on the Hill Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2011-01-01

    In this article, the author suggests a classroom challenge that will engage students in designing a house on the hill. He suggests teachers ask a local builder to come to the school to discuss the kinds of concerns that must be dealt with when building homes in cold environments. The use of dioramas and cardboard scale models would be very useful…

  9. Ocean Hill-Brownsville, 40 Years Later

    ERIC Educational Resources Information Center

    Kahlenberg, Richard D.

    2008-01-01

    Forty years ago--on May 9, 1968--the local school board in Brooklyn's black ghetto of Ocean Hill-Brownsville sent telegrams to 19 unionized educators, informing them that their employment in the district was terminated. Eighteen were white. One black teacher was mistakenly included on the list, but reinstated almost immediately after the error was…

  10. Tail prepivoting for the Hill estimator

    NASA Astrophysics Data System (ADS)

    Brito, Margarida; Moreira Freitas, Ana Cristina; Milhazes Freitas, Jorge

    2016-05-01

    It is well known that prepivoting reduces level error of confidence sets. We adapt this method to the context of the tail index estimation, introducing a procedure that we call tail prepivoting. We apply this procedure to the Hill estimator and establish its consistency.

  11. Jesse Stuart: Lessons from the Kentucky Hills.

    ERIC Educational Resources Information Center

    Sands, Lu

    1986-01-01

    Highlights events in the life of Jesse Stuart, who began his teaching career at the age of 17 in a remote one-room school in the Kentucky hills and went on to become widely recognized as teacher, lecturer, and significant regional writer. Emphasizes Stuart's love of teaching and his personal values. (JHZ)

  12. 27 CFR 9.121 - Warren Hills.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 1968 and 1973). (c) Boundary—(1) General. The Warren Hills viticultural area is located in Warren County, New Jersey. The beginning point of the following boundary description is the junction of the...). (2) Boundary Description. (i) From the beginning point, the boundary goes northeastward along...

  13. Chapel Hill, Berkeley Head Graduate Rankings.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1983

    1983-01-01

    Provides lists ranking the 25 largest producers of bachelor's, certified bachelor's, master's, and doctoral graduates in chemistry. University of North Carolina (Chapel Hill) is the nation's largest producer of bachelor's degree chemistry graduates while the University of California (Berkeley) is the largest producer of Ph.D. chemistry graduates.…

  14. 27 CFR 9.197 - Clements Hills.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... viticultural area is located in San Joaquin County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Clements Hills viticultural areas boundary is as follows— (1) The beginning... 9.3 miles on Liberty Road to its junction with the San Joaquin-Amador County line, north of...

  15. 27 CFR 9.197 - Clements Hills.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... viticultural area is located in San Joaquin County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Clements Hills viticultural areas boundary is as follows— (1) The beginning... 9.3 miles on Liberty Road to its junction with the San Joaquin-Amador County line, north of...

  16. 27 CFR 9.197 - Clements Hills.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... viticultural area is located in San Joaquin County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Clements Hills viticultural areas boundary is as follows— (1) The beginning... 9.3 miles on Liberty Road to its junction with the San Joaquin-Amador County line, north of...

  17. 27 CFR 9.197 - Clements Hills.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... viticultural area is located in San Joaquin County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Clements Hills viticultural areas boundary is as follows— (1) The beginning... 9.3 miles on Liberty Road to its junction with the San Joaquin-Amador County line, north of...

  18. 27 CFR 9.197 - Clements Hills.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... viticultural area is located in San Joaquin County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Clements Hills viticultural areas boundary is as follows— (1) The beginning... 9.3 miles on Liberty Road to its junction with the San Joaquin-Amador County line, north of...

  19. An Unlikely Student Hits Capitol Hill

    ERIC Educational Resources Information Center

    Hoover, Eric

    2009-01-01

    Todd Sollar, a laid-off autoworker from Ohio who is studying for an associate degree in engineering at Sinclair Community College, in Dayton, OH, went to Capitol Hill to help educate lawmakers about the importance of including support for community colleges in the economic-stimulus bill. Mr. Sollar came to Washington with Sinclair's president, and…

  20. 78 FR 65962 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... Forest Service Black Hills National Forest Advisory Board AGENCY: Forest Service, USDA. ACTION: Notice of cancellation of meeting of the Black Hills National Forest Advisory Board. SUMMARY: The U. S. Department of Agriculture, Forest Service, Black Hills National Forest cancelled the October 16, 2013 meeting of the...

  1. 77 FR 22755 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Black Hills National Forest Advisory Board AGENCY: USDA Forest Service. ACTION: Notice of cancellation of meetings of the Black Hills National Forest Advisory Board. SUMMARY: The U. S. Department of Agriculture, Forest Service, Black Hills National Forest was required...

  2. View of south boundary of Easter Hill project site, former ...

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

    View of south boundary of Easter Hill project site, former right of way for Hoffman Boulevard. Note reconstructed Easter Hill Building No. 6 at rear. Looking east - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  3. 27 CFR 9.169 - Red Hills Lake County.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Red Hills Lake County. 9... Red Hills Lake County. (a) Name. The name of the viticultural area described in this section is “Red Hills Lake County”. (b) Approved Map. The appropriate maps for determining the boundary of the Red...

  4. 27 CFR 9.169 - Red Hills Lake County.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Red Hills Lake County. 9... Red Hills Lake County. (a) Name. The name of the viticultural area described in this section is “Red Hills Lake County”. (b) Approved Map. The appropriate maps for determining the boundary of the Red...

  5. 27 CFR 9.169 - Red Hills Lake County.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Red Hills Lake County. 9... Red Hills Lake County. (a) Name. The name of the viticultural area described in this section is “Red Hills Lake County”. (b) Approved Map. The appropriate maps for determining the boundary of the Red...

  6. 27 CFR 9.169 - Red Hills Lake County.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Red Hills Lake County. 9... Red Hills Lake County. (a) Name. The name of the viticultural area described in this section is “Red Hills Lake County”. (b) Approved Map. The appropriate maps for determining the boundary of the Red...

  7. 27 CFR 9.169 - Red Hills Lake County.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Red Hills Lake County. 9... Red Hills Lake County. (a) Name. The name of the viticultural area described in this section is “Red Hills Lake County”. (b) Approved Map. The appropriate maps for determining the boundary of the Red...

  8. 3. HYDE STREET HILL: View to north looking down the ...

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

    3. HYDE STREET HILL: View to north looking down the Hyde Street hill from Lombard Street. The steepest hill on the present cable railway system, this grade exceeds 20%. - San Francisco Cable Railway, Washington & Mason Streets, San Francisco, San Francisco County, CA

  9. 27 CFR 9.136 - Texas Hill Country.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Texas Hill Country. 9.136... Texas Hill Country. (a) Name. The name of the viticultural area described in this section is “Texas Hill Country.” (b) Approved maps. The appropriate maps for determining the boundaries of the “Texas...

  10. 27 CFR 9.136 - Texas Hill Country.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Texas Hill Country. 9.136... Texas Hill Country. (a) Name. The name of the viticultural area described in this section is “Texas Hill Country.” (b) Approved maps. The appropriate maps for determining the boundaries of the “Texas...

  11. 27 CFR 9.136 - Texas Hill Country.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Texas Hill Country. 9.136... Texas Hill Country. (a) Name. The name of the viticultural area described in this section is “Texas Hill Country.” (b) Approved maps. The appropriate maps for determining the boundaries of the “Texas...

  12. 27 CFR 9.136 - Texas Hill Country.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Texas Hill Country. 9.136... Texas Hill Country. (a) Name. The name of the viticultural area described in this section is “Texas Hill Country.” (b) Approved maps. The appropriate maps for determining the boundaries of the “Texas...

  13. 27 CFR 9.136 - Texas Hill Country.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Texas Hill Country. 9.136... Texas Hill Country. (a) Name. The name of the viticultural area described in this section is “Texas Hill Country.” (b) Approved maps. The appropriate maps for determining the boundaries of the “Texas...

  14. Structure, stratigraphy, and origin of Husband Hill, Columbia Hills, Gusev Crater, Mars

    USGS Publications Warehouse

    McCoy, T.J.; Sims, M.; Schmidt, M.E.; Edwards, L.; Tornabene, L.L.; Crumpler, L.S.; Cohen, B. A.; Soderblom, L.A.; Blaney, D.L.; Squyres, S. W.; Arvidson, R. E.; Rica, J.W.; Treguier, E.; d'Uston, C.; Grant, J. A.; McSween, H.Y.; Golombek, M.P.; Haldemann, A.F.C.; de Souza, P.A.

    2008-01-01

    The strike and dip of lithologic units imaged in stereo by the Spirit rover in the Columbia Hills using three-dimensional imaging software shows that measured dips (15-32??) for bedding on the main edifice of the Columbia Hill are steeper than local topography (???8-10??). Outcrops measured on West Spur are conformable in strike with shallower dips (7-15??) than observed on Husband Hill. Dips are consistent with observed strata draping the Columbia Hills. Initial uplift was likely related either to the formation of the Gusev Crater central peak or ring or through mutual interference of overlapping crater rims. Uplift was followed by subsequent draping by a series of impact and volcaniclastic materials that experienced temporally and spatially variable aqueous infiltration, cementation, and alteration episodically during or after deposition. West Spur likely represents a spatially isolated depositional event. Erosion by a variety of processes, including mass wasting, removed tens of meters of materials and formed the Tennessee Valley primarily after deposition. This was followed by eruption of the Adirondack-class plains basalt lava flows which embayed the Columbia Hills. Minor erosion, impact, and aeolian processes have subsequently modified the Columbia Hills. Copyright 2008 by the American Geophysical Union.

  15. Lateglacial geomorphology in the Tweedsmuir Hills, Scotland - Implications for retreat patterns, glacier reconstruction and chronology.

    NASA Astrophysics Data System (ADS)

    Pearce, D.; Rea, B.; McDougall, D.

    2012-04-01

    The Tweedsmuir Hills, Southern Uplands, Scotland, contain excellent assemblages of glacial landforms, including hummocky moraine, classically associated with a Lateglacial deglaciation (c. 14.7 - 11.7 cal. ka BP) in the UK. Although initially documented in 1855, a detailed systematic geomorphological investigation has never been undertaken in the region, meaning reconstructions are patchy, outdated and lacking chronological control. This has resulted in conflicting styles of glaciation being inferred, with both plateau icefield and valley glaciers reconstructed in the Tweedsmuir Hills. Importantly, comprehensive numerical modelling experiments for the period, c. 38 -10.4 ka BP, predict a significant body of ice for the Tweedsmuir Hills at the onset and throughout the Younger Dryas (c. 12.9 - 11.7 cal. ka. BP). Field data, which at present, are missing means that the numerical modelling remains untested. Given the emerging evidence that ice-masses survived, during or throughout the Lateglacial in a number of regions in Scotland, the glacial geomorphology and reconstructions for this area will provide a key input of palaeo-glacier data for subsequent investigation of wider patterns of Lateglacial ice-mass distribution and climate gradients across the UK and NW Europe. Geomorphological mapping followed a morphostratigraphic approach using a combination of aerial photos, NEXTMapTM and mapping in the field using a ruggedized tablet PC, with built in GPS and ArcGIS 9.3. The glacial landforms indicate two separate landsystems. The first is characterised by elongate subglacial bedforms overriding the topography, trending SW to NE, suggested to be attributable to the Devensian glaciation. The second landsystem is characterised by closely spaced sharp crested moraines, oblique to the valley axis and confined by the topography, meltwater channels and single terrace systems, which are likely to have formed in a subsequent period of renewed glaciation i.e. Lateglacial. The

  16. Evidence in Support of Sulfide Partial Melting at Broken Hill Australia and Broken Hill, South Africa

    NASA Astrophysics Data System (ADS)

    Sparks, H. A.; Mavrogenes, J. A.

    2004-05-01

    In the past there has been much debate over the genesis of Broken Hill, Australia and Broken Hill, South Africa since many of the original characteristics have been obscured by high-grade metamorphism and intense deformation. The idea that a sulfide melt can form from partial melting of pre-existing ore during metamorphism was first proposed by Brett and Kullerud (1967 Economic Geology) and Lawrence (1967 Mineral Deposita), but was largely ignored due to a lack of direct field and experimental evidence. However, recent experimental support in the system PbS-Fe0.96S-ZnS-(1% Ag2S) determined a quaternary eutectic melt at 795 700° C at 5 kbar (Mavrogenes et al., 2001 Economic Geology), clear indirect evidence that at least some of the Broken Hill lodes partially melted during metamorphism. Features at both Broken Hill, Australia and Broken Hill, South Africa are consistent with the formation of a sulfide partial melt. At Broken Hill, Australia, abundant polyphase sulfide melt inclusions (SMINCs) have been identified within garnetite and quartz surrounding remobilised ore. Preliminary examination of garnetites associated with remobilised ore from Broken Hill, South Africa also reveals SMINCs similar to those documented at Broken Hill, Australia. This establishes that sulfide partial melting occurred, at least in the higher metamorphic grade portion of Broken Hill, South Africa. Development of a high temperature heating stage allows reflected light monitoring of submerged SMINCs during heating. The results indicate that quartz-hosted SMINCs from Broken Hill, Australia partially melt at temperatures as low as 420 700° C with total homogenisation occurring at temperatures well below peak metamorphic temperatures (810 700° C). Low melting point chalcophile elements (LMCE) increase in abundance as homogenisation temperatures decrease. This observation along with analysed bulk sulfide melt composition fractionation trends of Pb, Cu, Sb, Ag and Au similar to those observed

  17. The Regents of the University of California, Petitioner, vs. Allan Bakke, Respondent. On Writ of Certiorari to the Supreme Court of California.

    ERIC Educational Resources Information Center

    Supreme Court of the U. S., Washington, DC.

    The main question of this case is whether Allan Bakke was denied the equal protection of the laws in contravention of the 14th Amendment, solely because of his race, as the result of a racial quota admission policy. A statement of the case which reviews pertinent data such as the admission procedure of the medical school, Bakke's interview and…

  18. Cl-36 in polar ice, rainwater and seawater

    NASA Technical Reports Server (NTRS)

    Finkel, R. C.; Nishiizumi, K.; Elmore, D.; Ferraro, R. D.; Gove, H. E.

    1980-01-01

    Concentrations of the cosmogenic radioisotope Cl-36 in Antarctic ice, rain, and an upper limit of the seawater value are determined using van de Graaff accelerator high energy mass spectrometry. Cl-36 concentrations in Antarctic ice range between 2.5 to 8.7 x 10 to the 6th atoms Cl-36/kg, while those concentrations in samples collected at the Alan Hills ice field locations where meteorites have been brought to the surface by glacial flow and ablation are found to vary by more than a factor of three. This variation is attributed either to the effects of atmospheric mixing and scavenging or to radioactive decay in old ice. The Cl-36 concentration found in a present sample of rainwater is much lower than that reported in samples collected in the early 1960's, suggesting the occurrence of a decrease in the concentration of atmospheric Cl-36 derived from nuclear weapons tests over this time period.

  19. Gossan Hill, Victoria Island, Northwest Territories: An analogue for mine waste reactions within permafrost and implication for the subsurface mineralogy of Mars

    NASA Astrophysics Data System (ADS)

    Peterson, Ronald C.; Williamson, Marie-Claude; Rainbird, Robert H.

    2014-08-01

    Gossan Hill is located within the Minto Inlier in central Victoria Island, Northwest Territories (N 71.36697°, W 114.95155°). A study of the mineralogical associations and geological setting of this deposit indicates that it is an arrested hydrothermal system frozen in permafrost. From above, the hill stands out because of the topographic relief of 75 m and the orange-brown color of the surficial material. The surface of the hill is marked by areas of concentric color zonation up to 3 m across, with light gray centers surrounded by a yellow-orange ring that is surrounded by an orange-brown color that covers the rest of the surface of the hill. Trenches dug into these areas reveal that the central zone contains quartz and pyrite +/- native sulfur in a loose aggregate of sand-sized grains. This central area is surrounded by a zone dominated by gypsum and quartz with some jarosite. Beyond this, the surrounding surface consists of quartz, hematite, and amorphous iron oxides. The radial arrangement of the mineral assemblage indicates an increase in oxidation of sulfur from the center outward. Analysis of isotopic composition of the sulfur indicates the source of sulfur could be the underlying strata. The hill is underlain by inter-bedded carbonate and sulfate-evaporite sedimentary rocks of the Kilian formation in the upper part of the Neoproterozoic Shaler Super group. The sedimentary rocks were intruded by diabase sills of the 720 Ma Franklin igneous event, which crop out 2 km to the south of Gossan Hill. The soft friable nature of the deposit and the topographic relief of the hill indicate a post-glacial (Pleistocene) age of formation. Permafrost has maintained the disequilibrium mineral assemblage since the cessation of fluid flow. Extraction of the permafrost ice from the central zone yields a liquid with a pH of 2.3. The observed long-term persistence of pyrite encased within the acidic permafrost indicates that oxidation and dissolution reactions common in mine

  20. Ice Observatory

    NASA Astrophysics Data System (ADS)

    blugerman, n.

    2015-10-01

    My project is to make ice observatories to perceive astral movements as well as light phenomena in the shape of cosmic rays and heat, for example.I find the idea of creating an observation point in space, that in time will change shape and eventually disappear, in consonance with the way we humans have been approaching the exploration of the universe since we started doing it. The transformation in the elements we use to understand big and small transformations, within the universe elements.

  1. A generalized Hill-Wheeler ansatz

    NASA Astrophysics Data System (ADS)

    Nuñez, J.; Esebbag, C.; Martin, M. T.; Rebollo, L.; Plastino, A.

    1984-06-01

    The Hill-Wheeler ansatz for the total wave function, within the Generator Coordinate Method framework, is generalized by recourse to the theory of distributions. The ensuing approach allows one to obtain a basis that spans the collective subspace, without having to deal explicitly with the eigenvectors and eigenvalues of the overlap kernel. Applications to an exactly soluble model and anharmonic vibrations illustrate the present treatment.

  2. Hill Ciphers over Near-Fields

    ERIC Educational Resources Information Center

    Farag, Mark

    2007-01-01

    Hill ciphers are linear codes that use as input a "plaintext" vector [p-right arrow above] of size n, which is encrypted with an invertible n x n matrix E to produce a "ciphertext" vector [c-right arrow above] = E [middle dot] [p-right arrow above]. Informally, a near-field is a triple [left angle bracket]N; +, *[right angle bracket] that…

  3. Airborne laser swath mapping of the Denton Hills, Transantarctic Mountains, Antarctica: Applications for structural and glacial geomorphic mapping

    USGS Publications Warehouse

    Wilson, Terry; Csathó, Beata

    2007-01-01

    High-resolution digital elevation data acquired by airborne laser scanning (ALS) for the Denton Hills, along the coastal foothills of the Royal Society Range, Transantarctic Mountains, are examined for applications to bedrock and glacial geomorphic mapping. Digital elevation models (DEMs), displayed as shaded-relief images and slope maps, portray geomorphic landscape features in unprecedented detail across the region. Structures of both ductile and brittle origin, ranging in age from the Paleozoic to the Quaternary, can be mapped from the DEMs. Glacial features, providing a record of the limits of grounded ice, of lake paleoshorelines, and of proglacial lake-ice conveyor deposits, are also prominent on the DEMs. The ALS-derived topographic data have great potential for a range of mapping applications in regions of ice-free terrain in Antarctica

  4. The Rocks of the Columbia Hills

    NASA Technical Reports Server (NTRS)

    Squyres, Steven W.; Arvidson, Raymond E.; Blaney, Diana L.; Clark, Benton C.; Crumpler, Larry; Farrand, William H.; Gorevan, Stephen; Herkenhoff, Kenneth; Hurowitz, Joel; Kusack, Alastair; McSween, Harry Y.; Ming, Douglas W.; Morris, Richard V.; Ruff, Steven W.; Wang, Alian; Yen, Albert

    2006-01-01

    The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly-sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously-altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly-sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands, and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks, and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present.

  5. Late Pleistocene and early Holocene change in the Weddell Sea: a new climate record from the Patriot Hills, Ellsworth Mountains, West Antarctica

    NASA Astrophysics Data System (ADS)

    Turney, C. S.; Fogwill, C. J.; Rubino, M.; Etheridge, D. M.; van Ommen, T. D.; Moy, A. D.; Curran, M. A.

    2014-12-01

    The transition from the late Pleistocene to the Holocene (30 000-5000 years ago) was a period of considerable climate variability, which has been associated with changes in deep water formation and the intensity of the Meridional Overturning Circulation. Although numerous records exist across the North Atlantic region, few Antarctic ice core records have been obtained from the south. Here we exploit the potential of upwelling ancient ice - so-called blue ice areas (BIAs) - from the Patriot Hills in the Ellsworth Mountains to derive the first deuterium isotope record (dD) from continental Antarctica south of the Weddell Sea. Gas analysis and glaciological considerations provide a first relative chronology and provide new constraints on ice sheet dynamics in the region. Inferred temperature trends from the Patriot Hills BIA and snow pit suggest changing climate influences during the transition between the last glacial period and Holocene. Our results demonstrate the considerable potential of the Patriot Hills site for reconstructing past climate change in the south Atlantic region.

  6. The final days of Edgar Allan Poe: clues to an old mystery using 21st century medical science.

    PubMed

    Francis, Roger A

    This study examines all documented information regarding the final days and death of Edgar Allan Poe (1809-1849), in an attempt to determine the most likely cause of death of the American poet, short story writer, and literary critic. Information was gathered from letters, newspaper accounts, and magazine articles written during the period after Poe's death, and also from biographies and medical journal articles written up until the present. A chronology of Poe's final days was constructed, and this was used to form a differential diagnosis of possible causes of death. Death theories over the last 160 years were analyzed using this information. This analysis, along with a review of Poe's past medical history, would seem to support an alcohol-related cause of death. PMID:20222235

  7. Oxygen, carbon and U-series isotopes of aragonites from Vestfold Hills, Antarctica: Clues to geochemical processes in subglacial environments

    SciTech Connect

    Aharon, P. )

    1988-09-01

    Aragonites occurring in situ on the gneissic bedrock at Vestfold Hills, an ice-free coastal Antarctic oasis possess morphologic and petrographic characteristics typical of subglacial carbonate precipitates. The {sup 14}C chronology of the samples is invalidated by modern carbon contamination and a {sup 14}C/{sup 12}C reservoir correction of unknown magnitude. In contrast, U and Th isotope analyses suggest that the subglacial deposits can be treated as closed, datable, systems, if allowance is made for the excess {sup 230}Th derived from the small and variable detrital silicate fraction coexisting with the aragonites. The mean {sup 230}Th depositional age of 35,000 {plus minus} 2,000 yrs correlates with late isotope stage 3 of deep sea glacial chronology and represents the time when the Vestfold Hills were partially or completely buried under the advancing East Antarctic ice sheet. The survival of the aragonites following the ice sheet retreat during the Holocene is attributed to the extreme arid climate of the area. The aragonites are anomalously depleted in {sup 18}O and slightly depleted in {sup 13}C relative to SMOW and PDB standards, respectively ({delta}{sup 18}O = 15.7 {plus minus} 0.9{per thousand}; {delta}{sup 13}C = {minus}3.6 {plus minus} 0.4{per thousand}). The melt water with which the aragonites would have equilibrated at 0{degree}C is about 7 to 9{per thousand} more depleted in {sup 18}O relative to the extant basal ice source ({delta}{sup 18}O = {minus}41{per thousand}). Part of this enhanced {sup 18}O deficiency (i.e. 4 to 6{per thousand}) is ascribed to temporal shifts in {delta}{sup 18}O of the Antarctic ice, the rest to isotope effects of the subglacial hydrology. A model of subglacial aragonite precipitation is proposed on the basis of water flow between warm melting zones and cold freezing zones at the ice sheet sole.

  8. Scrambled Ice

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This complex area on the side of Europa which faces away from Jupiter shows several types of features which are formed by disruptions of Europa's icy crust. North is to the top of the image, taken by NASA's Galileo spacecraft, and the Sun illuminates the surface from the left. The prominent wide, dark bands are up to 20 kilometers (12 miles) wide and over 50 kilometers (30 miles) long. They are believed to have formed when Europa's icy crust fractured, separated and filled in with darker, 'dirtier' ice or slush from below. A relatively rare type of feature on Europa is the 15-kilometer-diameter (9.3-mile) impact crater in the lower left corner. The small number of impact craters on Europa's surface is an indication of its relatively young age. A region of chaotic terrain south of this impact crater contains crustal plates which have broken apart and rafted into new positions. Some of these 'ice rafts' are nearly 1 kilometer (about half a mile) across. Other regions of chaotic terrain are visible and indicate heating and disruption of Europa's icy crust from below. The youngest features in this scene are the long, narrow cracks in the ice which cut across all other features. One of these cracks is about 30 kilometers (18 miles) to the right of the impact crater and extends for hundreds of miles from the top to the bottom of the image.

    The image, centered near 23 degrees south latitude and 179 degrees longitude, covers an area about 240 by 215 kilometers (150 by 130 miles) across. The finest details that can be discerned in this picture are about 460 meters (500 yards) across. The image was taken as Galileo flew by Europa on March 29, 1998. The image was taken by the onboard solid state imaging system camera from an altitude of 23,000 kilometers (14,000 miles).

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech

  9. Confidence Hills Mineralogy and Chemin Results from Base of Mt. Sharp, Pahrump Hills, Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    Cavanagh, P. D.; Bish, D. L.; Blake, D. F.; Vaniman, D. T.; Morris, R. V.; Ming, D. W.; Rampe, E. B.; Achilles, C. N.; Chipera, S. J.; Treiman, A. H.; Downs, R. T.; Morrison, S. M.; Fendrich, K. V.; Yen, A. S.; Grotzinger, J.; Crisp, J. A.; Bristow, T. F.; Sarrazin, P. C.; Farmer, J. D.; Des Marais, D. J.; Stolper, E. M.; Morookian, J. M.; Wilson, M. A.; Spanovich, N.; Anderson, R. C.

    2015-01-01

    The Mars Science Laboratory (MSL) rover Curiosity recently completed its fourth drill sampling of sediments on Mars. The Confidence Hills (CH) sample was drilled from a rock located in the Pahrump Hills region at the base of Mt. Sharp in Gale Crater. The CheMin X-ray diffractometer completed five nights of analysis on the sample, more than previously executed for a drill sample, and the data have been analyzed using Rietveld refinement and full-pattern fitting to determine quantitative mineralogy. Confidence Hills mineralogy has several important characteristics: 1) abundant hematite and lesser magnetite; 2) a 10 angstrom phyllosilicate; 3) multiple feldspars including plagioclase and alkali feldspar; 4) mafic silicates including forsterite, orthopyroxene, and two types of clinopyroxene (Ca-rich and Ca-poor), consistent with a basaltic source; and 5) minor contributions from sulfur-bearing species including jarosite.

  10. High-resolution continuous-flow analysis setup for water isotopic measurement from ice cores using laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Emanuelsson, B. D.; Baisden, W. T.; Bertler, N. A. N.; Keller, E. D.; Gkinis, V.

    2015-07-01

    Here we present an experimental setup for water stable isotope (δ18O and δD) continuous-flow measurements and provide metrics defining the performance of the setup during a major ice core measurement campaign (Roosevelt Island Climate Evolution; RICE). We also use the metrics to compare alternate systems. Our setup is the first continuous-flow laser spectroscopy system that is using off-axis integrated cavity output spectroscopy (OA-ICOS; analyzer manufactured by Los Gatos Research, LGR) in combination with an evaporation unit to continuously analyze water samples from an ice core. A Water Vapor Isotope Standard Source (WVISS) calibration unit, manufactured by LGR, was modified to (1) enable measurements on several water standards, (2) increase the temporal resolution by reducing the response time and (3) reduce the influence from memory effects. While this setup was designed for the continuous-flow analysis (CFA) of ice cores, it can also continuously analyze other liquid or vapor sources. The custom setups provide a shorter response time (~ 54 and 18 s for 2013 and 2014 setup, respectively) compared to the original WVISS unit (~ 62 s), which is an improvement in measurement resolution. Another improvement compared to the original WVISS is that the custom setups have a reduced memory effect. Stability tests comparing the custom and WVISS setups were performed and Allan deviations (σAllan) were calculated to determine precision at different averaging times. For the custom 2013 setup the precision after integration times of 103 s is 0.060 and 0.070 ‰ for δ18O and δD, respectively. The corresponding σAllan values for the custom 2014 setup are 0.030, 0.060 and 0.043 ‰ for δ18O, δD and δ17O, respectively. For the WVISS setup the precision is 0.035, 0.070 and 0.042 ‰ after 103 s for δ18O, δD and δ17O, respectively. Both the custom setups and WVISS setup are influenced by instrumental drift with δ18O being more drift sensitive than δD. The σAllan

  11. High-resolution continuous flow analysis setup for water isotopic measurement from ice cores using laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Emanuelsson, B. D.; Baisden, W. T.; Bertler, N. A. N.; Keller, E. D.; Gkinis, V.

    2014-12-01

    Here we present an experimental setup for water stable isotopes (δ18O and δD) continuous flow measurements. It is the first continuous flow laser spectroscopy system that is using Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS; analyzer manufactured by Los Gatos Research - LGR) in combination with an evaporation unit to continuously analyze sample from an ice core. A Water Vapor Isotopic Standard Source (WVISS) calibration unit, manufactured by LGR, was modified to: (1) increase the temporal resolution by reducing the response time (2) enable measurements on several water standards, and (3) to reduce the influence from memory effects. While this setup was designed for the Continuous Flow Analysis (CFA) of ice cores, it can also continuously analyze other liquid or vapor sources. The modified setup provides a shorter response time (~54 and 18 s for 2013 and 2014 setup, respectively) compared to the original WVISS unit (~62 s), which is an improvement in measurement resolution. Another improvement compared to the original WVISS is that the modified setup has a reduced memory effect. Stability tests comparing the modified WVISS and WVISS setups were performed and Allan deviations (σAllan) were calculated to determine precision at different averaging times. For the 2013 modified setup the precision after integration times of 103 s are 0.060 and 0.070‰ for δ18O and δD, respectively. For the WVISS setup the corresponding σAllan values are 0.030, 0.060 and 0.043‰ for δ18O, δD and δ17O, respectively. For the WVISS setup the precision is 0.035, 0.070 and 0.042‰ after 103 s for δ18O, δD and δ17O, respectively. Both the modified setups and WVISS setup are influenced by instrumental drift with δ18O being more drift sensitive than δD. The σAllan values for δ18O of 0.30 and 0.18‰ for the modified (2013) and WVISS setup, respectively after averaging times of 104 s (2.78 h). The Isotopic Water Analyzer (IWA)-modified WVISS setup used during the

  12. Three-dimensional potential flow over hills and oval mounds

    NASA Technical Reports Server (NTRS)

    Siegel, R.

    1976-01-01

    An analysis was made of the potential flow behavior for an initially uniform flow passing over a single axisymmetric hill, an oval mound, and a combination of two hills. Small perturbation theory was used, and the resulting Laplace equation for the perturbation velocity potential was solved by using either a product solution or a Green's function. The three dimensional solution is of interest in calculating the pressure distribution around obstacles, the flow of pollutants carried by the wind, and the augmentation of wind velocity for windmill siting. The augmentation in velocity at the top of a hill was found to be proportional to the hill height relative to a characteristic width dimension of the hill. An axisymmetric hill produced about 20 percent less velocity increase than a two dimensional ridge having the same cross-sectional profile.

  13. Ice sheet margins and ice shelves

    NASA Technical Reports Server (NTRS)

    Thomas, R. H.

    1984-01-01

    The effect of climate warming on the size of ice sheet margins in polar regions is considered. Particular attention is given to the possibility of a rapid response to warming on the order of tens to hundreds of years. It is found that the early response of the polar regions to climate warming would be an increase in the area of summer melt on the ice sheets and ice shelves. For sufficiently large warming (5-10C) the delayed effects would include the breakup of the ice shelves by an increase in ice drainage rates, particularly from the ice sheets. On the basis of published data for periodic changes in the thickness and melting rates of the marine ice sheets and fjord glaciers in Greenland and Antarctica, it is shown that the rate of retreat (or advance) of an ice sheet is primarily determined by: bedrock topography; the basal conditions of the grounded ice sheet; and the ice shelf condition downstream of the grounding line. A program of satellite and ground measurements to monitor the state of ice sheet equilibrium is recommended.

  14. PLANS AND SECTIONS. WEIR SPILLWAY. TEXAS HILL CANAL STA. ...

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

    PLANS AND SECTIONS. WEIR SPILLWAY. TEXAS HILL CANAL - STA. 132+82.15. TEXAS HILL CANAL AND DISTRIBUTION SYSTEM. United States Department of Interior, Bureau of Reclamation; Gila Project, Arizona, Wellton-Mohawk Division. Drawing No. 50-D-3200, dated February 7, 1955, Denver, Colorado - Wellton-Mohawk Irrigation System, Relift Station, Texas Hill Canal 2.5, Northern Terminus of Avenue 51 East, approximately .5 mile south of Union Pacific Railroad, Wellton, Yuma County, AZ

  15. Icing: Accretion, Detection, Protection

    NASA Technical Reports Server (NTRS)

    Reinmann, John J.

    1994-01-01

    The global aircraft industry and its regulatory agencies are currently involved in three major icing efforts: ground icing; advanced technologies for in-flight icing; and tailplane icing. These three major icing topics correspondingly support the three major segments of any aircraft flight profile: takeoff; cruise and hold; and approach and land. This lecture addressess these three topics in the same sequence as they appear in flight, starting with ground deicing, followed by advanced technologies for in-flight ice protection, and ending with tailplane icing.

  16. Evaluation of Meterorite Amono Acid Analysis Data Using Multivariate Techniques

    NASA Technical Reports Server (NTRS)

    McDonald, G.; Storrie-Lombardi, M.; Nealson, K.

    1999-01-01

    The amino acid distributions in the Murchison carbonaceous chondrite, Mars meteorite ALH84001, and ice from the Allan Hills region of Antarctica are shown, using a multivariate technique known as Principal Component Analysis (PCA), to be statistically distinct from the average amino acid compostion of 101 terrestrial protein superfamilies.

  17. Dynamics of binary asteroids. I - Hill's case

    NASA Astrophysics Data System (ADS)

    Chauvineau, B.; Mignard, F.

    1990-02-01

    The present investigation of the dynamics of hypothesized binary (or multiple) asteroids attempts to evaluate the likelihood of their dynamic stability, giving attention to the trajectories of Hill's (1977) problem (including only the gravitational perturbation of the sun) to define the effects of solar perturbations on the relative motion of a binary asteroid. Only for the cases of close binary asteroids, can the Jacobian constant be unambiguously related to the semimajor axis of a weakly disturbed Keplerian ellipse. A greater likelihood is found for a stable asteroid with retrograde orbit, in both the synodic and the inertial frames, that with direct orbit.

  18. Earth and space scientists Visit Capitol Hill

    NASA Astrophysics Data System (ADS)

    O'Riordan, Catherine

    AGU's Office of Public Affairs organizes frequent opportunities for members to meet with Congress. Recently AGU members participated in two events: an annual Congressional Visits Day and the Coalition for National Science Funding congressional reception.Over 200 scientists and engineers met with key legislators and their staffs on Capitol Hill in Washington, D.C. as part of the 10th annual Science, Engineering, and Technology Congressional Visits Day (CVD) held on 10-11 May. In their meetings, participants advocated this year's CVD theme: Federally funded research secures our nation's future.

  19. Antarctic lakes (above and beneath the ice sheet): Analogues for Mars

    NASA Technical Reports Server (NTRS)

    Rice, J. W., Jr.

    1992-01-01

    The perennial ice covered lakes of the Antarctic are considered to be excellent analogues to lakes that once existed on Mars. Field studies of ice covered lakes, paleolakes, and polar beaches were conducted in the Bunger Hills Oasis, Eastern Antarctica. These studies are extended to the Dry Valleys, Western Antarctica, and the Arctic. Important distinctions were made between ice covered and non-ice covered bodies of water in terms of the geomorphic signatures produced. The most notable landforms produced by ice covered lakes are ice shoved ridges. These features form discrete segmented ramparts of boulders and sediments pushed up along the shores of lakes and/or seas. Sub-ice lakes have been discovered under the Antarctic ice sheet using radio echo sounding. These lakes occur in regions of low surface slope, low surface accumulations, and low ice velocity, and occupy bedrock hollows. The presence of sub-ice lakes below the Martian polar caps is possible. The discovery of the Antarctic sub-ice lakes raises possibilities concerning Martian lakes and exobiology.

  20. Arctic ice islands

    SciTech Connect

    Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.; Li, F.C.

    1988-01-01

    The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1) calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.

  1. Structure and Origin of the Columbia Hills, Gusev Crater, Mars

    NASA Astrophysics Data System (ADS)

    McCoy, Timothy; Sims, M.; Crumpler, L. S.; Cohen, B. A.; Blaney, D. L.; Schmidt, M. E.; Treguier, E.; d'Uston, C.; Rice, J. W.; Tornabene, L. L.; Squyres, S. W.; Arvidson, R. E.; Haldemann, A.

    2007-10-01

    The Mars Exploration Rover Spirit has yielded profound insights into features at millimeter to decimeter scales. However, the origin of the Columbia Hills has remained enigmatic given the traverse across one peak [1]. We present a geologic history of the Hills consistent with their morphology, bedding attitudes, and stratigraphy. The Columbia Hills form a triangle 4.2 by 2.3 km, are bounded by linear to slightly concave margins, lie near the center of Gusev Crater, and have peaks rising to 90 m. Bedding dips away from a NNE-SSW axis cutting the Tennessee Valley. Husband Hill dips (15-32°) are steeper than local topography ( 8-10°) and those on West Spur are conformable with greater scatter in strike and shallower dips (7-15°). Husband Hill is cored by volcaniclastic rocks and impact breccias altered to various extents (Wishstone, Watchtower and Descartes classes), ringed by ultramafic volcaniclastic rocks and sulfate-cemented sands (Algonquin and Peace classes), ringed by localized impact breccias and volcaniclastic deposits (West Spur and Home Plate) [2]. The Columbia Hills likely formed by (1) Uplift of the Gusev Crater central peak, raising the Hills to 3 km above the crater floor, assuming the Hills are deeply-rooted and subsequently buried. Uplift by overlapping crater rims is inconsistent with bedding attitudes, but may have modified the margins of the Hills. (2) Draping by impact and volcaniclastic rocks and sands with localized alteration and cementation. Fragile rocks (Peace) and in situ soils (Paso Robles) would not have survived Gusev Crater formation. (3) Mass wasting of the Tennessee Valley removed tens of meters from the peak of the Hills, exposing older units in the core, (4) Plains (Adirondack) basalts surrounded and embayed the Hills, and (5) Small impacts redistributed rocks. [1] Rice J.W. (2004) Fall AGU, #P23B-03. [2] Squyres S.W. et al. (2006) JGR 111, E02S11.

  2. Hill crossing during preheating after hilltop inflation

    NASA Astrophysics Data System (ADS)

    Antusch, Stefan; Nolde, David; Orani, Stefano

    2015-06-01

    In ``hilltop inflation'', inflation takes place when the inflaton field slowly rolls from close to a maximum of its potential (i.e. the ``hilltop'') towards its minimum. When the inflaton potential is associated with a phase transition, possible topological defects produced during this phase transition, such as domain walls, are efficiently diluted during inflation. It is typically assumed that they also do not reform after inflation, i.e. that the inflaton field stays on its side of the ``hill'', finally performing damped oscillations around the minimum of the potential. In this paper we study the linear and the non-linear phases of preheating after hilltop inflation. We find that the fluctuations of the inflaton field during the tachyonic oscillation phase grow strong enough to allow the inflaton field to form regions in position space where it crosses ``over the top of the hill'' towards the ``wrong vacuum''. We investigate the formation and behaviour of these overshooting regions using lattice simulations: rather than durable domain walls, these regions form oscillon-like structures (i.e. localized bubbles that oscillate between the two vacua) which should be included in a careful study of preheating in hilltop inflation.

  3. New type of hill-top inflation

    NASA Astrophysics Data System (ADS)

    Barvinsky, A. O.; Kamenshchik, A. Yu.; Nesterov, D. V.

    2016-01-01

    We suggest a new type of hill-top inflation originating from the initial conditions in the form of the microcanonical density matrix for the cosmological model with a large number of quantum fields conformally coupled to gravity. Initial conditions for inflation are set up by cosmological instantons describing underbarrier oscillations in the vicinity of the inflaton potential maximum. These periodic oscillations of the inflaton field and cosmological scale factor are obtained within the approximation of two coupled oscillators subject to the slow roll regime in the Euclidean time. This regime is characterized by rapid oscillations of the scale factor on the background of a slowly varying inflaton, which guarantees smallness of slow roll parameters epsilon and η of the following inflation stage. A hill-like shape of the inflaton potential is shown to be generated by logarithmic loop corrections to the tree-level asymptotically shift-invariant potential in the non-minimal Higgs inflation model and R2-gravity. The solution to the problem of hierarchy between the Planckian scale and the inflation scale is discussed within the concept of conformal higher spin fields, which also suggests the mechanism bringing the model below the gravitational cutoff and, thus, protecting it from large graviton loop corrections.

  4. Spirit's Express Route to 'Columbia Hills'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This map illustrates the Mars Exploration Rover Spirit's position as of sol 112 (April 26, 2004), near the crater called 'Missoula.' Like a train on a tight schedule, Spirit will make regular stops along the way to its ultimate destination, the 'Columbia Hills.' At each stop, or 'station,' the rover will briefly analyze the area's rocks and soils. Each tick mark on the rover's route represents one sol's worth of travel, or about 60 to 70 meters (200 to 230 feet). Rover planners estimate that Spirit will reach the hills around mid-June. Presently, the rover is stopped at a site called 'Plains Station.'

    The color thermal data show how well different surface features hold onto heat. Red indicates a higher thermal inertia associated with rocky terrain (cooler in the day, warmer at night); blue indicates a lower thermal inertia associated with smaller particles and fewer rocks (warmer at night, cooler in the day). During its traverse, Spirit will document the causes of these thermal variations.

    The map comprises data from the camera on NASA's Mars Global Surveyor orbiter and the thermal emission imaging system on NASA's Mars Odyssey orbiter.

  5. Spirit's Express Route to 'Columbia Hills'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This map illustrates the Mars Exploration Rover Spirit's position as of sol 112 (April 26, 2004), near the crater called 'Missoula.' Like a train on a tight schedule, Spirit will make regular stops along the way to its ultimate destination, the 'Columbia Hills.' At each stop, or 'station,' the rover will briefly analyze the area's rocks and soils. Each tick mark on the rover's route represents one sol's worth of travel, or about 60 to 70 meters (200 to 230 feet). Rover planners estimate that Spirit will reach the hills around mid-June. Presently, the rover is stopped at a site called 'Plains Station.'

    The color thermal data show how well different surface features hold onto heat. Red indicates warmth; blue indicates coolness. Areas with higher temperatures are more likely to be rocky, as rocks absorb heat. Lower temperatures denote small particles and fewer rocks. During its traverse, Spirit will document the causes of these temperature variations.

    The map comprises data from the camera on NASA's Mars Global Surveyor orbiter and the thermal emission imaging system on NASA's Mars Odyssey orbiter.

  6. Stochastic ice stream dynamics

    NASA Astrophysics Data System (ADS)

    Mantelli, Elisa; Bertagni, Matteo Bernard; Ridolfi, Luca

    2016-08-01

    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution.

  7. Sea ice ecosystems.

    PubMed

    Arrigo, Kevin R

    2014-01-01

    Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters. PMID:24015900

  8. Stochastic ice stream dynamics.

    PubMed

    Mantelli, Elisa; Bertagni, Matteo Bernard; Ridolfi, Luca

    2016-08-01

    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution. PMID:27457960

  9. Top Sounder Ice Penetration

    NASA Astrophysics Data System (ADS)

    Porter, D. L.; Goemmer, S. A.; Sweeney, J. H.

    2014-12-01

    Ice draft measurements are made as part of normal operations for all US Navy submarines operating in the Arctic Ocean. The submarine ice draft data are unique in providing high resolution measurements over long transects of the ice covered ocean. The data has been used to document a multidecadal drop in ice thickness, and for validating and improving numerical sea-ice models. A submarine upward-looking sonar draft measurement is made by a sonar transducer mounted in the sail or deck of the submarine. An acoustic beam is transmitted upward through the water column, reflecting off the bottom of the sea ice and returning to the transducer. Ice thickness is estimated as the difference between the ship's depth (measured by pressure) and the acoustic range to the bottom of the ice estimated from the travel time of the sonar pulse. Digital recording systems can provide the return off the water-ice interface as well as returns that have penetrated the ice. Typically, only the first return from the ice hull is analyzed. Information regarding ice flow interstitial layers provides ice age information and may possibly be derived with the entire return signal. The approach being investigated is similar to that used in measuring bottom sediment layers and will involve measuring the echo level from the first interface, solving the reflection loss from that transmission, and employing reflection loss versus impedance mismatch to ascertain ice structure information.

  10. Measurement of ice thickness (icing) in aeronautics

    NASA Technical Reports Server (NTRS)

    Hansman, R. John; Kirby, Mark S. JR.

    1988-01-01

    Pulsed ultrasonic techniques have been used to measure the formation of ice in flight in an icing wind tunnel with a precision of + or - 0.5 mm. Two icing regimes, humid and dry, are identified. Both natural and artificial conditions are considered. On the basis of ice formation rates obtained by the ultrasound technique and the observed surface conditions, it is found that the heat transfer coefficients are larger in the wind tunnel tests than in actual flight, presumably due to the higher level of turbulence in the wind tunnel tests. Profiles obtained during flight under natural conditions are compared with mechanical-type measurements and with the results of stereographic analysis.

  11. Further Insights into the Allan-Herndon-Dudley Syndrome: Clinical and Functional Characterization of a Novel MCT8 Mutation

    PubMed Central

    Yoon, Grace; Visser, Theo J.

    2015-01-01

    Background Mutations in the thyroid hormone (TH) transporter MCT8 have been identified as the cause for Allan-Herndon-Dudley Syndrome (AHDS), characterized by severe psychomotor retardation and altered TH serum levels. Here we report a novel MCT8 mutation identified in 4 generations of one family, and its functional characterization. Methods Proband and family members were screened for 60 genes involved in X-linked cognitive impairment and the MCT8 mutation was confirmed. Functional consequences of MCT8 mutations were studied by analysis of [125I]TH transport in fibroblasts and transiently transfected JEG3 and COS1 cells, and by subcellular localization of the transporter. Results The proband and a male cousin demonstrated clinical findings characteristic of AHDS. Serum analysis showed high T3, low rT3, and normal T4 and TSH levels in the proband. A MCT8 mutation (c.869C>T; p.S290F) was identified in the proband, his cousin, and several female carriers. Functional analysis of the S290F mutant showed decreased TH transport, metabolism and protein expression in the three cell types, whereas the S290A mutation had no effect. Interestingly, both uptake and efflux of T3 and T4 was impaired in fibroblasts of the proband, compared to his healthy brother. However, no effect of the S290F mutation was observed on TH efflux from COS1 and JEG3 cells. Immunocytochemistry showed plasma membrane localization of wild-type MCT8 and the S290A and S290F mutants in JEG3 cells. Conclusions We describe a novel MCT8 mutation (S290F) in 4 generations of a family with Allan-Herndon-Dudley Syndrome. Functional analysis demonstrates loss-of-function of the MCT8 transporter. Furthermore, our results indicate that the function of the S290F mutant is dependent on cell context. Comparison of the S290F and S290A mutants indicates that it is not the loss of Ser but its substitution with Phe, which leads to S290F dysfunction. PMID:26426690

  12. OVERVIEW OF GOLD HILL MILL, ROAD, AND WHITE PINE TALC ...

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

    OVERVIEW OF GOLD HILL MILL, ROAD, AND WHITE PINE TALC MINE LOOKING EAST. THE OPENING TO THE TALC MINE IS IN THE DARK AREA AT CENTER LEFT EDGE. WARM SPRINGS CAMP IS OUT OF FRAME TO THE RIGHT. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  13. STREAMLINES IN STRATIFIED FLOW OVER A THREE-DIMENSIONAL HILL

    EPA Science Inventory

    A fluid modeling study was performed in the EPA Fluid Modeling Facility's stratified towing tank to determine the effects of stratification on the flow field over a three-dimensional hill. Streamlines in the stratified flow over an axisymmetric hill were marked with a dye tracer ...

  14. VIEW LOOKING WEST TOWARD RESERVOIR HILL. THE SPRR HOTEL WAS ...

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

    VIEW LOOKING WEST TOWARD RESERVOIR HILL. THE SPRR HOTEL WAS LOCATED IN THE STRIPED AREA AT THE BOTTOM OF THE IMAGE, AND THE TRACK RAN BETWEEN THE HILL AND THE HOTEL. - Southern Pacific Railroad Water Settling Reservoir, Yuma Crossing, south bank of Colorado River at foot of Madison Avenue, Yuma, Yuma County, AZ

  15. 78 FR 76100 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-16

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Black Hills National Forest Advisory Board AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Black Hills National Forest Advisory Board (Board) will... Committee Act of 1972 (5 U.S.C. App. II), the Forest and Rangeland Renewable Resources Planning Act of...

  16. 78 FR 73187 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-05

    ... Forest Service Black Hills National Forest Advisory Board AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Black Hills National Forest Advisory Board (Board) will meet in Rapid City, South.... II), the Forest and Rangeland Renewable Resources Planning Act of 1974 (16 U.S.C. 1600 et.seq.),...

  17. 77 FR 75120 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-19

    ... Forest Service Black Hills National Forest Advisory Board AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Black Hills National Forest Advisory Board will meet in Rapid City, South Dakota...) (FACA); and the Forest and Rangeland Renewable Resources Planning Act of 1974 (16 U.S.C. 1600...

  18. View of south boundary of Easter Hill project site for ...

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

    View of south boundary of Easter Hill project site for right of way for Hoffman Boulevard. Buildings No. 11 and 14 at right in trees. Looking west - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  19. VIEW TO SOUTHEAST TOWARD QUARTERMASTER BUILDINGS GROUP AND RESERVOIR HILL, ...

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

    VIEW TO SOUTHEAST TOWARD QUARTERMASTER BUILDINGS GROUP AND RESERVOIR HILL, FROM AMMUNITION (IGLOO) HILL. (Part 2 of a 3 view panorama; see also CA-2398-J-1 and CA-2398-16.) - Hamilton Field, East of Nave Drive, Novato, Marin County, CA

  20. AmeriFlux US-Blk Black Hills

    SciTech Connect

    Meyers, Tilden

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Blk Black Hills. Site Description - The Black Hills tower was established by the Institute for Atmospheric Studies of the South Dakota School of Mines and Technology.

  1. View of sports field and Easter Hill at west side ...

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

    View of sports field and Easter Hill at west side of project site. Looking southwest - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  2. View of sports field and Easter Hill at west side ...

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

    View of sports field and Easter Hill at west side of project site. Looking west - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  3. View of sports field from Easter Hill looking at intersection ...

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

    View of sports field from Easter Hill looking at intersection of South Twenty-Sixth Street and Foothill Avenue at left center rear. Buildings No. 36, 35, 25, 27, and 29, from left to right. Looking northeast - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  4. Spectral parameter power series representation for Hill's discriminant

    SciTech Connect

    Khmelnytskaya, K.V.; Rosu, H.C.

    2010-11-15

    We establish a series representation of the Hill discriminant based on the spectral parameter power series (SPPS) recently introduced by Kravchenko. We also show the invariance of the Hill discriminant under a Darboux transformation and employing the Mathieu case the feasibility of this type of series for numerical calculations of the eigenspectrum.

  5. 27 CFR 9.162 - Sta. Rita Hills.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Sta. Rita Hills. 9.162.... Rita Hills. (a) Name. The name of the viticultural area described in this section is “Sta. Rita Hills”. For purposes of part 4 of this chapter, “Sta. Rita Hills” is a term of viticultural significance....

  6. 27 CFR 9.162 - Sta. Rita Hills.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Sta. Rita Hills. 9.162.... Rita Hills. (a) Name. The name of the viticultural area described in this section is “Sta. Rita Hills”. For purposes of part 4 of this chapter, “Sta. Rita Hills” is a term of viticultural significance....

  7. 27 CFR 9.162 - Sta. Rita Hills.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Sta. Rita Hills. 9.162.... Rita Hills. (a) Name. The name of the viticultural area described in this section is “Sta. Rita Hills”. For purposes of part 4 of this chapter, “Sta. Rita Hills” is a term of viticultural significance....

  8. 27 CFR 9.162 - Sta. Rita Hills.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Sta. Rita Hills. 9.162.... Rita Hills. (a) Name. The name of the viticultural area described in this section is “Sta. Rita Hills”. For purposes of part 4 of this chapter, “Sta. Rita Hills” is a term of viticultural significance....

  9. 27 CFR 9.162 - Sta. Rita Hills.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Sta. Rita Hills. 9.162.... Rita Hills. (a) Name. The name of the viticultural area described in this section is “Sta. Rita Hills”. For purposes of part 4 of this chapter, “Sta. Rita Hills” is a term of viticultural significance....

  10. 83. GENERAL VIEW FROM NORTH END OF GUN HILL PLATFORM ...

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

    83. GENERAL VIEW FROM NORTH END OF GUN HILL PLATFORM OF 3RD AVENUE EL SHOWING THE SOUTHBOUND TRACK APPROACH INTO GUN HILL STATION. 7TH AVENUE EXPRESS EL ABOVE. - Interborough Rapid Transit Company, Third Avenue Elevated Line, Borough of the Bronx, New York County, NY

  11. Accounting for imperfect detection in Hill numbers for biodiversity studies

    USGS Publications Warehouse

    Broms, Kristin M.; Hooten, Mevin B.; Fitzpatrick, Ryan M.

    2015-01-01

    The occupancy-based Hill number estimators are always at their asymptotic values (i.e. as if an infinite number of samples have been taken for the study region), therefore making it easy to compare biodiversity between different assemblages. In addition, the Hill numbers are computed as derived quantities within a Bayesian hierarchical model, allowing for straightforward inference.

  12. 27 CFR 9.188 - Horse Heaven Hills.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Horse Heaven Hills. 9.188... Horse Heaven Hills. (a) Name. The name of the viticultural area described in this section is “Horse Heaven Hills”. For purposes of part 4 of this chapter, “Horse Heaven Hills” and “Horse Heaven” are...

  13. 27 CFR 9.188 - Horse Heaven Hills.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Horse Heaven Hills. 9.188... Horse Heaven Hills. (a) Name. The name of the viticultural area described in this section is “Horse Heaven Hills”. For purposes of part 4 of this chapter, “Horse Heaven Hills” and “Horse Heaven” are...

  14. 27 CFR 9.188 - Horse Heaven Hills.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Horse Heaven Hills. 9.188... Horse Heaven Hills. (a) Name. The name of the viticultural area described in this section is “Horse Heaven Hills”. For purposes of part 4 of this chapter, “Horse Heaven Hills” and “Horse Heaven” are...

  15. 27 CFR 9.188 - Horse Heaven Hills.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Horse Heaven Hills. 9.188... Horse Heaven Hills. (a) Name. The name of the viticultural area described in this section is “Horse Heaven Hills”. For purposes of part 4 of this chapter, “Horse Heaven Hills” and “Horse Heaven” are...

  16. "This Delightfull Garden": "Rabbit Hill" and the Pastoral Tradition.

    ERIC Educational Resources Information Center

    Jordan, Anne Devereaux

    1997-01-01

    Contends that Robert Lawson's children's book "Rabbit Hill" (1944) falls within the genre of pastoral literature, in the tradition of Edmund Spenser's "Faerie Queen." Examines the history of the genre and finds reasons for classifying Lawson's book as pastoral. Cites classic elements in "Rabbit Hill." Gives five questions for stimulating student…

  17. 3. BUNKER HILL LEAD SMELTER. VIEW IS FROM CIA TO ...

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

    3. BUNKER HILL LEAD SMELTER. VIEW IS FROM CIA TO THE SOUTHWEST. BUILDINGS NOTED IN ID-29-2 APPEAR, IN ADDITION TO DRY ORE PLANT AND BONNOT COAL PULVERIZING EQUIPMENT BUILDING ON THE RIGHT. - Bunker Hill Lead Smelter, Bradley Rail Siding, Kellogg, Shoshone County, ID

  18. 1. BUNKER HILL LEAD SMELTER. VIEW IS FROM CENTRAL IMPOUNDMENT ...

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

    1. BUNKER HILL LEAD SMELTER. VIEW IS FROM CENTRAL IMPOUNDMENT AREA LOOKING SOUTH. PLANT DRY IS IN CENTER FOREGROUND, SLAG FUMING PLANT IS IN RIGHT FOREGROUND, AND BAG HOUSE IS IN RIGHT BACKGROUND. VARIOUS PLANT STACKS ARE ALSO VISIBLE. - Bunker Hill Lead Smelter, Bradley Rail Siding, Kellogg, Shoshone County, ID

  19. 2. BUNKER HILL LEAD SMELTER. VIEW IS FROM CIA TO ...

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

    2. BUNKER HILL LEAD SMELTER. VIEW IS FROM CIA TO THE SOUTH. IN FOREGROUND, PLANT DRY, SLAG FUMING PLANT, BLAST FURNACE, SMELTER OFFICE, LEAD AND SILVER REFINERIES ARE VISIBLE, L. TO R. HIGH VELOCITY FLUE LEADS FROM LOWER PLANT TO BAG HOUSE AND STACKS AT TOP OF SMELTING FACILITY. - Bunker Hill Lead Smelter, Bradley Rail Siding, Kellogg, Shoshone County, ID

  20. Seeing mountains in mole hills: geographical-slant perception

    NASA Technical Reports Server (NTRS)

    Proffitt, D. R.; Creem, S. H.; Zosh, W. D.; Kaiser, M. K. (Principal Investigator)

    2001-01-01

    When observers face directly toward the incline of a hill, their awareness of the slant of the hill is greatly overestimated, but motoric estimates are much more accurate. The present study examined whether similar results would be found when observers were allowed to view the side of a hill. Observers viewed the cross-sections of hills in real (Experiment 1) and virtual (Experiment 2) environments and estimated the inclines with verbal estimates, by adjusting the cross-section of a disk, and by adjusting a board with their unseen hand to match the inclines. We found that the results for cross-section viewing replicated those found when observers directly face the incline. Even though the angles of hills are directly evident when viewed from the side, slant perceptions are still grossly overestimated.

  1. Decay of isolated hills and saddles on Si(001)

    NASA Astrophysics Data System (ADS)

    Kirschbaum, Pierre; Brendel, Lothar; Roos, Kelly R.; Horn-von Hoegen, Michael; Heringdorf, Frank-J. Meyer zu

    2016-08-01

    We discuss the high temperature decay of isolated hills and saddle points on Si(001). Using in situ dark-field imaging in low energy electron microscopy, we track the movement of individual steps during high temperature annealing. We find different temperature dependent decay rates for the top of the hill compared to a saddle point with low step density that is present in the vicinity of the hill. The decay rate of the hill is always higher than the decay rate at the saddle. The two rates converge with increasing temperature and become equal at temperatures above 1060 °C. We also report an alternating fast and low decay rate for the layer-by-layer decay of the hills. This surprising finding is independent of temperature and is explained by macroscopic strain in the sample.

  2. Seeing mountains in mole hills: geographical-slant perception.

    PubMed

    Proffitt, D R; Creem, S H; Zosh, W D

    2001-09-01

    When observers face directly toward the incline of a hill, their awareness of the slant of the hill is greatly overestimated, but motoric estimates are much more accurate. The present study examined whether similar results would be found when observers were allowed to view the side of a hill. Observers viewed the cross-sections of hills in real (Experiment 1) and virtual (Experiment 2) environments and estimated the inclines with verbal estimates, by adjusting the cross-section of a disk, and by adjusting a board with their unseen hand to match the inclines. We found that the results for cross-section viewing replicated those found when observers directly face the incline. Even though the angles of hills are directly evident when viewed from the side, slant perceptions are still grossly overestimated. PMID:11554677

  3. Comparisons of calculated and measured helicopter noise near instrument hill

    NASA Technical Reports Server (NTRS)

    Bass, Henry E.; You, Chulsoo

    1993-01-01

    The polar parabolic equation (POPE) method solves for the diffraction of sound by a curved surface including a realistic sound speed profile. POPE is outlined briefly to describe diffraction which propagates the field over a hill. Experimental data are compared with POPE predictions using the measured sound speed profile and ground impedance. Two trial cases are considered for the comparisons: the helicopter located at the base of the hill and far away from the base of the hill, respectively. The physical mechanisms for sound propagation over a hill are examined with and of POPE calculations and experimental data. The shedding of rays from the hillside gives an interference effect with a wave along the flat surface beyond the base of a hill.

  4. Magnetotelluric investigation of the Vestfold Hills and Rauer Group, East Antarctica

    NASA Astrophysics Data System (ADS)

    Peacock, J. R.; Selway, K.

    2016-04-01

    The Vestfold Hills and Rauer Group in East Antarctica have contrasting Archean to Neoproterozoic geological histories and are believed to be juxtaposed along a suture zone that now lies beneath the Sørsdal Glacier. Exact location and age of this suture zone are unknown, as is its relationship to regional deformation associated with the amalgamation of East Gondwana. To image the suture zone, magnetotelluric (MT) data were collected in Prydz Bay, East Antarctica, mainly along a profile crossing the Sørsdal Glacier and regions inland of the Vestfold Hills and Rauer Group islands. Time-frequency analysis of the MT time series yielded three important observations: (1) Wind speeds in excess of ˜8 m/s reduce coherence between electric and magnetic fields due to charged wind-blown particles of ice and snow. (2) Estimation of the MT transfer function is best between 1000 and 1400 UT when ionospheric Hall currents enhance the magnetic source field. (3) Nonplanar source field effects were minimal but detectable and removed from estimation of the MT transfer function. Inversions of MT data in 2-D and 3-D produce similar resistivity models, where structures in the preferred 3-D resistivity model correlate strongly with regional magnetic data. The electrically conductive Rauer Group is separated from the less conductive Vestfold Hills by a resistive zone under the Sørsdal Glacier, which is interpreted to be caused by oxidation during suturing. Though a suture zone has been imaged, no time constrains on suturing can be made from the MT data.

  5. Magnetotelluric investigation of the Vestfold Hills and Rauer Group, East Antarctica

    USGS Publications Warehouse

    Peacock, Jared R.; Selway, Katherine

    2016-01-01

    The Vestfold Hills and Rauer Group in East Antarctica have contrasting Archean to Neoproterozoic geological histories and are believed to be juxtaposed along a suture zone that now lies beneath the Sørsdal Glacier. Exact location and age of this suture zone are unknown, as is its relationship to regional deformation associated with the amalgamation of East Gondwana. To image the suture zone, magnetotelluric (MT) data were collected in Prydz Bay, East Antarctica, mainly along a profile crossing the Sørsdal Glacier and regions inland of the Vestfold Hills and Rauer Group islands. Time-frequency analysis of the MT time series yielded three important observations: (1) Wind speeds in excess of ∼8 m/s reduce coherence between electric and magnetic fields due to charged wind-blown particles of ice and snow. (2) Estimation of the MT transfer function is best between 1000 and 1400 UT when ionospheric Hall currents enhance the magnetic source field. (3) Nonplanar source field effects were minimal but detectable and removed from estimation of the MT transfer function. Inversions of MT data in 2-D and 3-D produce similar resistivity models, where structures in the preferred 3-D resistivity model correlate strongly with regional magnetic data. The electrically conductive Rauer Group is separated from the less conductive Vestfold Hills by a resistive zone under the Sørsdal Glacier, which is interpreted to be caused by oxidation during suturing. Though a suture zone has been imaged, no time constrains on suturing can be made from the MT data.

  6. Motivations of female Black Hills deer hunters

    USGS Publications Warehouse

    Gigliotti, Larry M.; Covelli Metcalf, Elizabeth

    2016-01-01

    State fish and wildlife agencies are particularly interested in attracting female participation because of the potential to offset declining participation in hunting. Understanding female hunters’ motivations will be critical for designing effective recruitment and retention programs for women hunters. Although female participation in hunting is increasing, males still outnumber females by about tenfold. Gender differences in deer hunters were explored by comparing ratings of eight motivations (social, nature, excitement, meat, challenge, trophy, extra hunting opportunity, and solitude). Hunter types were defined by hunters’ selection of the most important motivation for why they like Black Hills deer hunting. Overall, females and males were relatively similar in their ratings of the eight motivations, and we found 85% gender similarity in the selection of the most important motivation. Women were slightly more motivated by the food aspect of the hunt while men placed slightly more value on the hunt as a sporting activity.

  7. After Conquering 'Husband Hill,' Spirit Moves On

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The first explorer ever to scale a summit on another planet, NASA's Mars Exploration Rover Spirit has begun a long trek downward from the top of 'Husband Hill' to new destinations. As shown in this 180-degree panorama from east of the summit, Spirit's earlier tracks are no longer visible. They are off to the west (to the left in this view). Spirit's next destination is 'Haskin Ridge,' straight ahead along the edge of the steep cliff on the right side of this panorama.

    The scene is a mosaic of images that Spirit took with the navigation camera on the rover's 635th Martian day, or sol, (Oct. 16, 2005) of exploration of Gusev Crater on Mars. This view is presented in a cylindrical projection with geometric seam correction.

  8. Meteorological analysis for Fenton Hill, 1979

    SciTech Connect

    Barr, S.; Wilson, S.K.

    1981-01-01

    Three years of meteorological data have been collected at the Fenton Hill site to establish a local climatic baseline, transport and diffusion climatology, and an initial site for an eventual Valles Caldera meteorological network. Tower-based wind and temperature data at 15 m above ground were supplemented during 1979 with precipitation, humidity and pressure measurements, and a limited program of upper winds. Preliminary analysis of the data has been made to identify major topographic and meteorological driving forces affecting the local climatic variations on diurnal and seasonal time scales. The site is quite high and exposed enough tht external influences such as gradient wind flow and thunderstorms tend to dominate over purely local driving forces in determining climate. Locally generated wind circulations are identifiable at night but tend to be weak and sporadic. The presence of topographic obstacles on the 10- to 100-km scale is observed in the winds.

  9. Seeing sodomy: Fanny Hill's blinding vision.

    PubMed

    Kopelson, K

    1992-01-01

    One of the oddest and most erotic moments in Cleland's Fanny Hill occurs when Fanny is knocked "senseless" by a voyeuristic vision of two young men having anal intercourse. This sodomitical passage demonstrates a dominant culture's strong phobic attraction to a socially peripheral Other against which it defines itself. The passage also represents two types of transgression. On one level, it records an inversion of sex, gender, and class paradigms that structure bourgeois subjectivity. On another level, the passage also transgresses signification itself, exploding as well as inverting those paradigms, in a movement that recalls Barthes's distinction between the coded "studium" of the pornographic and the uncoded "punctum" of the erotic. This transgressive exemption from meaning might well be read, in a Barthesian sense, as true sexual enfranchisement in that, for Barthes, the liberation of sexuality requires the release of sexuality from meaning, and from transgression as meaning. PMID:1431071

  10. AGU climate scientists visit Capitol Hill

    NASA Astrophysics Data System (ADS)

    Hankin, Erik

    2012-02-01

    On 1 February 2012, AGU teamed with 11 other scientific societies to bring 29 scientists researching various aspects of climate change to Washington, D. C., for the second annual Climate Science Day on Capitol Hill. The participants represented a wide range of expertise, from meteorology to agriculture, paleoclimatology to statistics, but all spoke to the reality of climate change as demonstrated in their scientific research. With Congress debating environmental regulations and energy policy amid tight fiscal pressures, it is critical that lawmakers have access to the best climate science to help guide policy decisions. The scientists met with legislators and their staff to discuss the importance of climate science for their districts and the nation and offered their expertise as an ongoing resource to the legislators.

  11. Who's Afraid of the Hill Boundary?

    NASA Astrophysics Data System (ADS)

    Montgomery, Richard

    2014-11-01

    The Jacobi-Maupertuis metric allows one to reformulate Newton's equations as geodesic equations for a Riemannian metric which degenerates at the Hill boundary. We prove that a JM geodesic which comes sufficiently close to a regular point of the boundary contains pairs of conjugate points close to the boundary. We prove the conjugate locus of any point near enough to the boundary is a hypersurface tangent to the boundary. Our method of proof is to reduce analysis of geodesics near the boundary to that of solutions to Newton's equations in the simplest model case: a constant force. This model case is equivalent to the beginning physics problem of throwing balls upward from a fixed point at fixed speeds and describing the resulting arcs, see Fig. 2.

  12. Doped Artificial Spin Ice

    NASA Astrophysics Data System (ADS)

    Olson Reichhardt, Cynthia; Libal, Andras; Reichhardt, Charles

    We examine square and kagome artificial spin ice for colloids confined in arrays of double-well traps. Unlike magnetic artificial spin ices, colloidal and vortex artificial spin ice realizations allow creation of doping sites through double occupation of individual traps. We find that doping square and kagome ice geometries produces opposite effects. For square ice, doping creates local excitations in the ground state configuration that produce a local melting effect as the temperature is raised. In contrast, the kagome ice ground state can absorb the doping charge without generating non-ground-state excitations, while at elevated temperatures the hopping of individual colloids is suppressed near the doping sites. These results indicate that in the square ice, doping adds degeneracy to the ordered ground state and creates local weak spots, while in the kagome ice, which has a highly degenerate ground state, doping locally decreases the degeneracy and creates local hard regions.

  13. Greenland Ice Flow

    NASA Video Gallery

    Greenland looks like a big pile of snow seen from space using a regular camera. But satellite radar interferometry helps us detect the motion of ice beneath the snow. Ice starts flowing from the fl...

  14. Allan Brooks, naturalist and artist (1869-1946): the travails of an early twentieth century wildlife illustrator in North America.

    PubMed

    Winearls, Joan

    2008-01-01

    British by birth Allan Cyril Brooks (1869-1946) emigrated to Canada in the 1880s, and became one of the most important North American bird illustrators during the first half of the twentieth century. Brooks was one of the leading ornithologists and wildlife collectors of the time; he corresponded extensively with other ornithologists and supplied specimens to many major North American museums. From the 1890s on he hoped to support himself by painting birds and mammals, but this was not possible in Canada at that time and he was forced to turn to American sources for illustration commissions. His work can be compared with that of his contemporary, the leading American bird painter Louis Agassiz Fuertes (1874-1927), and there are striking similarities and differences in their careers. This paper discusses the work of a talented, self-taught wildlife artist working in a North American milieu, his difficulties and successes in a newly developing field, and his quest for Canadian recognition. PMID:19569391

  15. Ash and Steam, Soufriere Hills Volcano, Monserrat

    NASA Technical Reports Server (NTRS)

    2002-01-01

    International Space Station crew members are regularly alerted to dynamic events on the Earth's surface. On request from scientists on the ground, the ISS crew observed and recorded activity from the summit of Soufriere Hills on March 20, 2002. These two images provide a context view of the island (bottom) and a detailed view of the summit plume (top). When the images were taken, the eastern side of the summit region experienced continued lava growth, and reports posted on the Smithsonian Institution's Weekly Volcanic Activity Report indicate that 'large (50-70 m high), fast-growing, spines developed on the dome's summit. These spines periodically collapsed, producing pyroclastic flows down the volcano's east flank that sometimes reached the Tar River fan. Small ash clouds produced from these events reached roughly 1 km above the volcano and drifted westward over Plymouth and Richmond Hill. Ash predominately fell into the sea. Sulfur dioxide emission rates remained high. Theodolite measurements of the dome taken on March 20 yielded a dome height of 1,039 m.' Other photographs by astronauts of Montserrat have been posted on the Earth Observatory: digital photograph number ISS002-E-9309, taken on July 9, 2001; and a recolored and reprojected version of the same image. Digital photograph numbers ISS004-E-8972 and 8973 were taken 20 March, 2002 from Space Station Alpha and were provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

  16. Ice rule correlations in stuffed spin ice

    NASA Astrophysics Data System (ADS)

    Aldus, R. J.; Fennell, T.; Deen, P. P.; Ressouche, E.; Lau, G. C.; Cava, R. J.; Bramwell, S. T.

    2013-01-01

    Stuffed spin ice is a chemical variation of a spin ice material like Ho2Ti2O7 in which extra magnetic ions are inserted into the crystal structure. Previous studies have shown that the degree of stuffing has very little effect on the residual entropy in the system, which takes a value very close to the spin ice entropy. We argue, however, that the observation of this entropy does not imply long range coherence of the ice rules, that determine the local spin configurations. We have characterized deviations from the ice rules by means of a polarized neutron diffraction study of a single crystal of Ho2+δTi2-δO7-δ/2 with δ = 0.3. Our results demonstrate that the ice rules in stuffed spin ice are strictly valid only over a relatively short range, and that at longer range stuffed spin ice exhibits some characteristics of a ‘cluster glass’, with a tendency to more conventional ferromagnetic correlations.

  17. Wheel Tracks from Landing Site to Hills

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2

    Wheel tracks left by the NASA rover Spirit's 3-kilometer (2-mile) trek from its landing site to the 'Columbia Hills' are visible in this orbital view from the Mars Orbiter Camera on NASA's Mars Global Surveyor. Spirit's rover track shows up nicely from orbit because the surfaces disrupted and churned by the wheels are darker than the surrounding, dust-coated plain. North is up.

    The largest crater in the view, dubbed 'Bonneville Crater,' is about 210 meters (230 yards) in diameter. The picture is a composite of Mars Orbiter Camera image R15-02643, taken on March 30, 2004, when Spirit was near the south rim of Bonneville Crater, and image R20-01024, taken Aug. 18, 2004, when Spirit was climbing the hills' western spur, seen in the picture's bottom right corner.

    New Dark Streak Near Spirit In figure 1, frames taken from orbit 20 weeks apart (top pair) and by the NASA rover Spirit at ground level (bottom) show the formation of a new dark streak on the ground in the area where Spirit was driving inside Mars' Gusev Crater in April 2004. The new dark streak and other dark streaks in the area are believed to result from dust devils removing brighter dust from the surface.

    The upper frames were taken by the Mars Orbiter Camera aboard NASA's Mars Global Surveyor. They are from the same pair of images combined to create the orbital view of the NASA rover Spirit's trail from the rover's landing site to the 'Columbia Hills.' The orbiter took the upper-left picture on March 30, 2004 (Spirit's 85th martian day, or sol). It took the upper-right picture on Aug. 18, 2004 (Spirit's sol 223). A dark streak occurs in the larger crater in the lower right quarter of the August image. This streak was not present when the March image was obtained. Inspection of the lower image, which was taken by Spirit's navigation camera when the rover was at

  18. Ice electrode electrolytic cell

    DOEpatents

    Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

    1993-04-06

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  19. Ice electrode electrolytic cell

    DOEpatents

    Glenn, David F.; Suciu, Dan F.; Harris, Taryl L.; Ingram, Jani C.

    1993-01-01

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  20. Ice electrode electrolytic cell

    SciTech Connect

    Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

    1992-12-31

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  1. Beacon Hill end moraine, Boston: new explanation of an important urban feature

    USGS Publications Warehouse

    Kaye, Clifford A.

    1976-01-01

    The usefulness of geology to engineers is in direct proportion to how well it helps us predict the subsurface; these predictions, in turn, depend on our knowledge of the geomorphic processes that molded the terrain. The uncertainties of interpretation are particularly great in glaciated terrain because our understanding of both glacial processes and history is so incomplete, a fact well illustrated in Beacon Hill. Recent construction activities in the eastern part of the hill, until now classified as a drumlin, have shown that it is better interpreted as an end moraine formed by a Wisconsonian glacial readvance. Instead of the firm till that was anticipated as foundation material, excavations exposed a complex of sand, gravel, and clay, with only minor zones of till. The structure of these deposits strongly suggests that originally they were plates of the glacial bed that froze to the glacier and were transported englacially. Thrust faulting and other deformations are glacial structures formed within the ice in the glacier's terminal zone. In spite of the complex englacial history, these deposits lost little of their original appearance and intergranular relationships. Upon deglaciation, the frozen moraine thawed, and slumping formed complex secondary structures on the ridge's lower flanks.

  2. Quantifying the role of mitigation hills in reducing tsunami runup

    NASA Astrophysics Data System (ADS)

    Marras, S.; Suckale, J.; Lunghino, B.; Giraldo, F.; Hood, K. M.

    2015-12-01

    Coastal communities around the world are being encouraged to plant or restore vegetation along their shores for the purpose of mitigating tsunami damage. A common setup for these projects is to develop 'mitigation hills' - an ensemble of vegetated hills along the coast - instead of one continuous stretch of vegetation. The rationale behind a staggered-hill setup is to give tree roots more space to grow and deepen. From a fluid-dynamical point of view, however, staggered mitigation hills may have significant drawbacks such as diverting the flow into the low-lying areas of the park, which could entail strong currents in the narrow channels between the hills and lead to erosion of the hills from the sides. The goal of this study is to quantify how mitigation hills affect tsunami runup and to provide constraints on the design of mitigation hills that mitigate tsunami damage using numerical simulations. Our computations of tsunami runup are based on the non-linear shallow water equation solved through a fully implicit, high-order, discontinuous Galerkin method. The adaptive computational grid is fitted to the hill topography to capture geometric effects accurately. A new dynamic subgrid-scale eddy viscosity originally designed for large eddy simulation of compressible flows is used for stabilization and to capture the obstacle-generated turbulence. We have carefully benchmarked our model in 1D and 2D against classical test cases. The included figure shows an example run of tsunami runup through coastal mitigation hills. In the interest of providing generalizable results, we perform a detailed scaling analysis of our model runs. We find that the protective value of mitigation hills depends sensitively on the non-linearity of the incoming wave and the relative height of the wave to the hills. Our simulations also suggest that the assumed initial condition is consequential and we hence consider a range of incoming waves ranging from a simple soliton to a more realistic N

  3. Ice Formation on Wings

    NASA Technical Reports Server (NTRS)

    Ritz, L

    1939-01-01

    This report makes use of the results obtained in the Gottingen ice tunnel in which the atmospheric conditions are simulated and the process of ice formation photographed. The effect of ice formation is threefold: 1) added weight to the airplane; 2) a change in the lift and drag forces; 3) a change in the stability characteristics.

  4. The Antarctic Ice.

    ERIC Educational Resources Information Center

    Radok, Uwe

    1985-01-01

    The International Antarctic Glaciological Project has collected information on the East Antarctic ice sheet since 1969. Analysis of ice cores revealed climatic history, and radar soundings helped map bedrock of the continent. Computer models of the ice sheet and its changes over time will aid in predicting the future. (DH)

  5. Experiments in Ice Physics.

    ERIC Educational Resources Information Center

    Martin, P. F.; And Others

    1978-01-01

    Describes experiments in ice physics that demonstrate the behavior and properties of ice. Show that ice behaves as an ionic conductor in which charge is transferred by the movement of protons, its electrical conductivity is highly temperature-dependent, and its dielectric properties show dramatic variation in the kilohertz range. (Author/GA)

  6. Technology for Ice Rinks

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Ron Urban's International Ice Shows set up portable ice rinks for touring troupes performing on temporary rinks at amusement parks, sports arenas, dinner theaters, shopping malls and civic centers. Key to enhanced rink portability, fast freezing and maintaining ice consistency is a mat of flexible tubing called ICEMAT, an offshoot of a solar heating system developed by Calmac, Mfg. under contract with Marshall.

  7. Ice Versus Rock

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Olson, Eric A.; Dehm, Janet

    2005-01-01

    During a snow bank exploration, students noticed "ice caves," or pockets, in some of the larger snow banks, usually below darker layers. Most of these caves had many icicles hanging inside. Students offered reasonable explanations of ice cave formation--squirrels, kids, snow blowers--and a few students came close to the true ice cave-formation…

  8. Scientific contributions of A. V. Hill: exercise physiology pioneer.

    PubMed

    Bassett, David R

    2002-11-01

    Beginning in 1910, A. V. Hill performed careful experiments on the time course of heat production in isolated frog muscle. His research paralleled that of the German biochemist Otto Meyerhof, who measured the changes in muscle glycogen and lactate during contractions and recovery. For their work in discovering the distinction between aerobic and anaerobic metabolism, Hill and Meyerhof were jointly awarded the 1922 Nobel Prize for Physiology or Medicine. Because of Hill's interest in athletics, he sought to apply the concepts discovered in isolated frog muscle to the exercising human. Hill and his colleagues made measurements of O(2) consumption on themselves and other subjects running around an 85-m grass track. In the process of this work, they defined the terms "maximum O(2) intake," "O(2) requirement," and "steady state of exercise." Other contributions of Hill include his discoveries of heat production in nerve, the series elastic component, and the force-velocity equation in muscle. Around the time of World War II, Hill was a leading figure in the Academic Assistance Council, which helped Jewish scientists fleeing Nazi Germany to relocate in the West. He served as a member of the British Parliament from 1940 to 1945 and as a scientific advisor to India. Hill's vision and enthusiasm attracted many scientists to the field of exercise physiology, and he pointed the way toward many of the physiological adaptations that occur with physical training. PMID:12381740

  9. Descent from the Summit of 'Husband Hill' (False Color)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    In late November 2005 while descending 'Husband Hill,' NASA's Mars Exploration Rover Spirit took the most detailed panorama so far of the 'Inner Basin,' the rover's next target destination. Spirit acquired the 405 individual images that make up this 360-degree view of the surrounding terrain using five different filters on the panoramic camera. The rover took the images on Martian days, or sols, 672 to 677 (Nov. 23 to 28, 2005 -- the Thanksgiving holiday weekend).

    This image is a false-color rendering using camera's 750-, 530-, and 430-nanometer filters, emphasizing some colors more than others to enhance striking but subtle color differences among rocks, soils, hills, and plains.

    'Home Plate,' a bright, semi-circular feature scientists hope to investigate, is harder to discern in this image than in earlier views taken from higher up the hill. Spirit acquired this more oblique view, known as the 'Seminole panorama,' from about halfway down the south flank of Husband Hill, 50 meters (164 feet) or so below the summit. Near the center of the panorama, on the horizon, are 'McCool Hill' and 'Ramon Hill,' named, like Husband Hill, in honor of the fallen astronauts of the space shuttle Columbia. Husband Hill is visible behind the rover, on the right and left sides of the panorama. An arc of rover tracks made while avoiding obstacles and getting into position to examine rock outcrops can be traced over a long distance by zooming in to explore the panorama in greater detail.

    Spirit is now significantly farther downhill toward the center of this panorama, en route to Home Plate and other enigmatic soils and outcrop rocks in the quest to uncover the history of Gusev Crater and the 'Columbia Hills.'

  10. Seasat and floating ice

    NASA Technical Reports Server (NTRS)

    Weeks, W. F.

    1974-01-01

    Data collected by SEASAT would be useful in developing predictive physical models for the drift and deformation of sea ice, for estimating the heat budget of the polar seas, for the optimum routing of shipping through pack ice areas, for the design of both offshore structures and shipping capable of surviving in heavy pack ice, and for the tracking of large icebergs and ice islands. The instrument package for SEASAT-A is particularly useful for studying sea ice in that the Coherent Imaging Radar (CIR), the Scanning Multifrequency Microwave Radiometer (SMMR) and the Compressed Pulse Radar Altimeter (CPRA) are not limited by the presence of clouds.

  11. Alaska marine ice atlas

    SciTech Connect

    LaBelle, J.C.; Wise, J.L.; Voelker, R.P.; Schulze, R.H.; Wohl, G.M.

    1982-01-01

    A comprehensive Atlas of Alaska marine ice is presented. It includes information on pack and landfast sea ice and calving tidewater glacier ice. It also gives information on ice and related environmental conditions collected over several years time and indicates the normal and extreme conditions that might be expected in Alaska coastal waters. Much of the information on ice conditions in Alaska coastal waters has emanated from research activities in outer continental shelf regions under assessment for oil and gas exploration and development potential. (DMC)

  12. Summer Sea ice in the Pacific Arctic sector from the CHINARE-2010 cruise

    NASA Astrophysics Data System (ADS)

    Ackley, S. F.; Xie, H.; Lei, R.; Huang, W.; Chinare 2010 Arctic Sea Ice Group

    2010-12-01

    N (from August 21 to August 24). In this area, the ice concentration varied from 70-100%, melt pond varied from 20-50% of ice, ridged ice varied from 10-30% of ice, and floe size was dominated by 10’s km to several km’s in one or two dimensions. The overall ice thickness decreased southward from 1.8-2m to 0.6-1m. The ice type of the area is multiyear ice dominated, with small portion of first year ice. In the area from ~85°N to 83.5°N, we see dirty ice (brownish, rich hills and valleys, mostly multiyear ice), varying from 10-20% of ice. Similar dirty ice was only seen from 72°N-75°N in the northward leg (July 24-29), then not seen until the northern region. The ice situation in this cruise will be compared with that from the CHINARE-2008 cruise, in a similar area and season, so change of the two years for this sector of Arctic Ocean during the middle-later summer can be deduced.

  13. GIA Ice Models

    NASA Astrophysics Data System (ADS)

    Kachuck, Samuel; Cathles, Larry; Amantov, Aleksey

    2013-04-01

    Defining the ice load in a way that avoids circularity is perhaps the most difficult aspect of GIA modeling. At any instant of past time the global land-supported ice load must honor the meltwater curve and the known edges of the ice, but within these constraints the ice mass can be swapped to a considerable extent between the various glacial systems and parts of those systems. In our models, ice thickness is controlled by the effective basal shear stress (EBSS). This parameter incorporates the sub-ice lithology (e.g., whether the ice rests on sediment of crystalline rock), the relative local snow accumulation rate, and the local basal shear strength (which presumably depends most strongly on sub-ice temperature). The effective basal shear stress can be fairly easily modified to construct an ice model. The ice model is evaluated by the geological reasonability of its changes in EBSS in space and time, and by how well it matches measured GIA data. The risk that an incorrect earth model can be forced to fit the GIA data by manipulating the ice model (the circularity mentioned above) can be minimized by evaluating the longest wavelength deformations (peripheral bulge behavior) before proceeding to the shorter wavelength deformations (local emergence variations). The poster will describe how we have proceeded in this fashion to develop a framework for interpreting GIA data in Norway. The poster will be augmented by computer software that compares emergence data to models at specific sites in Norway.

  14. ICE SLURRY APPLICATIONS

    PubMed Central

    Kauffeld, M.; WANG, M. J.; Goldstein, V.; Kasza, K. E.

    2011-01-01

    The role of secondary refrigerants is expected to grow as the focus on the reduction of greenhouse gas emissions increases. The effectiveness of secondary refrigerants can be improved when phase changing media are introduced in place of single phase media. Operating at temperatures below the freezing point of water, ice slurry facilitates several efficiency improvements such as reductions in pumping energy consumption as well as lowering the required temperature difference in heat exchangers due to the beneficial thermo-physical properties of ice slurry. Research has shown that ice slurry can be engineered to have ideal ice particle characteristics so that it can be easily stored in tanks without agglomeration and then be extractable for pumping at very high ice fraction without plugging. In addition ice slurry can be used in many direct contact food and medical protective cooling applications. This paper provides an overview of the latest developments in ice slurry technology. PMID:21528014

  15. ICE SLURRY APPLICATIONS.

    PubMed

    Kauffeld, M; Wang, M J; Goldstein, V; Kasza, K E

    2010-12-01

    The role of secondary refrigerants is expected to grow as the focus on the reduction of greenhouse gas emissions increases. The effectiveness of secondary refrigerants can be improved when phase changing media are introduced in place of single phase media. Operating at temperatures below the freezing point of water, ice slurry facilitates several efficiency improvements such as reductions in pumping energy consumption as well as lowering the required temperature difference in heat exchangers due to the beneficial thermo-physical properties of ice slurry. Research has shown that ice slurry can be engineered to have ideal ice particle characteristics so that it can be easily stored in tanks without agglomeration and then be extractable for pumping at very high ice fraction without plugging. In addition ice slurry can be used in many direct contact food and medical protective cooling applications. This paper provides an overview of the latest developments in ice slurry technology. PMID:21528014

  16. Of Ice and Microbes

    NASA Astrophysics Data System (ADS)

    Deming, Jody

    2006-12-01

    Inuit hunters of the North have long recognized ice as the natural state of water from which life flows on Earth. Although unaware of the microscopic world, they chart changes in properties of ice and water that derive from a succession of microbial inhabitants. Scientific hunters of the West have largely overlooked all but the warmest of ices as dynamic scenes of microbial life, considering the frozen realm to archive life forms instead. Deeply frozen glacial ice on Earth does appear to preserve microbes effectively, but isn't the ocean beneath the geologically dynamic ice of Europa believed too salty? Aren't the subsurface ices of Mars expected to be rich in all manner of mineralogical impurities? Wherever salt and other mineral impurities are sufficiently abundant in Earth ice, the ice contains interior liquid water that can range from nano-layer films on grain surfaces (glacial ice) to a porous network of brine (Arctic winter sea ice down to 20°C). Other recent studies of saline ices have indicated a world of interacting life forms, with viruses infecting bacteria in brines at -12°C (the lowest temperature tested), the domains of Bacteria and Archaea undergoing succession in winter ices (down to -28°C), and evidence that cellular maintenance may go forward incrementally even below the eutectic of seawater (-55°C). Microbes are also known to alter the physical properties of their icy homes by producing exopolymers that further depress the freezing point, either directly or by entraining more salt into the ice. Even the most inhospitable of ices to human hunters may contain interior oases for microbes, in control to some degree of their own space. In considering the habitability of icy worlds beyond Earth, we'd do well to learn more about the evolutionary prowess of microbes in adapting to conditions beyond our warm-blooded imaginations.

  17. Evolution of the Puente Hills Thrust Fault

    NASA Astrophysics Data System (ADS)

    Bergen, K. J.; Shaw, J. H.; Dolan, J. F.

    2013-12-01

    This study aims to assess the evolution of the blind Puente Hills thrust fault system (PHT) by determining its age of initiation, lateral propagation history, and changes in slip rate over time. The PHT presents one of the largest seismic hazards in the United States, given its location beneath downtown Los Angeles. The PHT is comprised of three fault segments: the Los Angeles (LA), Santa Fe Springs (SFS), and Coyote Hills (CH). The LA and SFS segments are characterized by growth stratigraphy where folds formed by uplift on the fault segments have been continually buried by sediment from the Los Angeles and San Gabriel rivers. The CH segment has developed topography and is characterized by onlapping growth stratigraphy. This depositional setting gives us the unique opportunity to measure uplift on the LA and SFS fault segments, and minimum uplift on the CH fault segment, as the difference in sediment thicknesses across the buried folds. We utilize depth converted oil industry seismic reflection data to image the fold geometries. Identifying time-correlative stratigraphic markers for slip rate determination in the basin has been a problem for researchers in the past, however, as the faunal assemblages observed in wells are time-transgressive by nature. To overcome this, we utilize the sequence stratigraphic model and well picks of Ponti et al. (2007) as a basis for mapping time-correlative sequence boundaries throughout our industry seismic reflection data from the present to the Pleistocene. From the Pleistocene to Miocene we identify additional sequence boundaries in our seismic reflection data from imaged sequence geometries and by correlating industry well formation tops. The sequence and formation top picks are then used to build 3-dimensional surfaces in the modeling program Gocad. From these surfaces we measure the change in thicknesses across the folds to obtain uplift rates between each sequence boundary. Our results show three distinct phases of

  18. How does the Porosity of Interstellar Ice Affect Chemical Complexity and Deuteration Exchange?

    NASA Astrophysics Data System (ADS)

    Fraser, Helen Jane; Noble, Jennifer; Hill, Catherine Rachel; Bowron, Daniel; Youngs, Tristan; Loerting, Thomas; Mitteldorfer, Christian; Millar, James; Elkind, Pavel; Cousan, Stephane; Lui, Yuan; Ojamae, Lars

    2015-08-01

    The porosity of interstellar water ice, Amorphous Solid Water (ASW), greatly enhances the ability of ice to uptake, then release small gas adsorbates. This provides the strongest evidence that interstellar ices must be porous, accounting for the differences between predicted and observed gas-phase abundances, and provides a mechanism to enhance reagent diversity for complex chemistry in the ice. However, no dangling OH (d-OH) bond features, to-date associated with ice porosity, have been reported in interstellar ice spectra, so some conclude that interstellar ices must be non-porous, given that the d-OH spectra disappear in laboratory studies when ASW is energetically processed. But are d-OH features and gas-uptake reliable experimental measures of ice porosity? Here we combine fundamental studies of ASW with observational data to determine ASW porosity and understand its role in the chemical evolution of interstellar ices.We show upper-limit detections of d-OH in observational spectra towards a handful of sources (Fraser et al (2015)). Laboratory experiments on selective irradiation of d-OH features (Noble et al (2013), (2014)), combined with quantum chemical calculations (Lui et al (2015)), show that the d-OH bonds probe the density of defect sites in the surface and sub-surface structure. Consequently surfaces with d-OH bonds are significantly more reactive and therefore promote chemical complexity across extra-terrestrial regions where they are found, but do not reflect ice porosity.Our neutron scattering data show that ASW ices actually contain cylindrical pores of around 10 Å diameter (Mitteldorfer et al (2014)). The pore collapse process can only be initiated by long range molecular diffusion at T > 121 K, and follows complex kinetics (Hill et al (2015a); such effects can be reproduced by molecular dynamics simulations of ASW ice-heating (Elkind et al (2015): Miller et al (2015)), and are directly linked to deuteration exchange. We explain the implications

  19. 265. Dennis Hill, Photographer April 1998 DETAIL VIEW OF TENSION ...

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

    265. Dennis Hill, Photographer April 1998 DETAIL VIEW OF TENSION EYE BARS AT CANTILEVER TRUSS, FACING SOUTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  20. 266. Dennis Hill, Photographer June 1998 DETAIL VIEW OF TENSION ...

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

    266. Dennis Hill, Photographer June 1998 DETAIL VIEW OF TENSION EYE BARS AND COMPRESSION MEMBERS ABOVE UPPER DECK, FACING SOUTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  1. 35. VIEW OF HOWLAND HILL ROAD, JEDEDIAH SMITH STATE PARK. ...

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

    35. VIEW OF HOWLAND HILL ROAD, JEDEDIAH SMITH STATE PARK. CRESCENT CITY, DEL NORTE COUNTY, CALIFORNIA. LOOKING E. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

  2. VIEW OF HOWLAND HILL ROAD, JEDEDIAH SMITH STATE PARK. CRESCENT ...

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

    VIEW OF HOWLAND HILL ROAD, JEDEDIAH SMITH STATE PARK. CRESCENT CITY, DEL NORTH COUNTY, CALIFORNIA. LOOKING ESE. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

  3. VIEW OF HOWLAND HILL ROAD, JEDEDIAH SMITH STATE PARK. CRESCENT ...

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

    VIEW OF HOWLAND HILL ROAD, JEDEDIAH SMITH STATE PARK. CRESCENT CITY, DEL NORTE COUNTY, CALIFORNIA. LOOKING E. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

  4. VIEW OF HOWLAND HILL ROAD, JEDEDIAH SMITH STATE PARK. CRESCENT ...

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

    VIEW OF HOWLAND HILL ROAD, JEDEDIAH SMITH STATE PARK. CRESCENT CITY, DEL NORTE COUNTY, CALIFORNIA. LOOKING W. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

  5. Hill Stability in the Finite Density N-Body Problem

    NASA Astrophysics Data System (ADS)

    Scheeres, Daniel J.

    2016-05-01

    A Celestial Mechanics system is Hill Stable if its components cannot escape from each other. Such stability is difficult to prove for general Celestial Mechanics problems with N ≥ 3 bodies interacting with each other. This is in part due to the ability of two bodies to come arbitrarily close to each other, freeing kinetic energy that can be used for an additional body to escape. When considering bodies with finite density, meaning that they have finite sizes and their mass centers cannot come arbitrarily close to each other, this pathway to escape has specific limits that make the determination of Hill Stability feasible. This opens up new definitions of Hill Stability that can be used to determine energetic thresholds at which a rubble pile body with sufficient angular momentum can shed mass components of various sizes. This talk will review recent advances in Hill Stability with direct application to the interaction of self-gravitating rubble pile bodies.

  6. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #12 EARLY RED BRICK HOUSE, Elk and Prospect Sts., Galena, Illinois - Galena Doorways, Red Brick House, Elk & Prospect Streets, Galena, Jo Daviess County, IL

  7. Dennis Hill, Photographer May 1998 DETAIL VIEW OF WINDOW AT ...

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

    Dennis Hill, Photographer May 1998 DETAIL VIEW OF WINDOW AT TORPEDO ASSEMBLY BUILDING, FACING SOUTHEAST - Torpedo Assembly Building, Eastern end of Yerba Buena Island, San Francisco, San Francisco County, CA

  8. EXTERIOR, A view looking northwest from far hill toward the ...

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

    EXTERIOR, A view looking northwest from far hill toward the Mounds complex and the HH Building - Department of Energy, Mound Facility, Hydrolysis House Building (HH Building), One Mound Road, Miamisburg, Montgomery County, OH

  9. 6. Historic American Buildings Survey Joseph Hill, Photographer April 1, ...

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

    6. Historic American Buildings Survey Joseph Hill, Photographer April 1, 1936 MANTEL 1352 W. Washington Blvd., Chicago - Chicago Ironwork, William M. Strong Estate (Cast Iron House & Gate), 1352 West Washington Boulevard, Chicago, Cook County, IL

  10. 4. Historic American Buildings Survey Joseph Hill, Photographer April 5, ...

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

    4. Historic American Buildings Survey Joseph Hill, Photographer April 5, 1936 INRON WINDOW GRILL, 1352 W. WASHINGTON ST. CHICAGO - Chicago Ironwork, William M. Strong Estate (Cast Iron House & Gate), 1352 West Washington Boulevard, Chicago, Cook County, IL

  11. 2. Historic American Buildings Survey Joseph Hill, Photographer May 10, ...

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

    2. Historic American Buildings Survey Joseph Hill, Photographer May 10, 1936 CAST IRON GATE AT 1352 W. Washington Blvd., Chicago - Chicago Ironwork, William M. Strong Estate (Cast Iron House & Gate), 1352 West Washington Boulevard, Chicago, Cook County, IL

  12. Context view looking west from hill with tree in foreground. ...

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

    Context view looking west from hill with tree in foreground. Entist Mountains are in distance. - Badger Mountain Lookout, .125 mile northwest of Badger Mountain summit, East Wenatchee, Douglas County, WA

  13. 215. Dennis Hill, Photographer May 1998 DETAIL VIEW OF STRAND ...

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

    215. Dennis Hill, Photographer May 1998 DETAIL VIEW OF STRAND SHOES AND STORM CABLE EYE BARS IN YERBA BUENA ANCHORAGE, FACING EAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  14. 81. VIEW NORTH ON WEST SIDE OF GUN HILL PLATFORM ...

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

    81. VIEW NORTH ON WEST SIDE OF GUN HILL PLATFORM SHOWING LAMP STANDARDS FOR NIGHT LIGHTNING. - Interborough Rapid Transit Company, Third Avenue Elevated Line, Borough of the Bronx, New York County, NY

  15. View looking east over coal tipple toward Friendship Hill, home ...

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

    View looking east over coal tipple toward Friendship Hill, home of Albert Gallatin, in right background behine bridge. - Monongahela Railroad, New Geneva Bridge, Spanning Monongahela River, South of Lock & Dam No. 7, New Geneva, Fayette County, PA

  16. Symmetric periodic solutions of the Hill's problem. I

    NASA Astrophysics Data System (ADS)

    Batkhin, A. B.

    2013-07-01

    The planar circular Hill's problem is considered, as well as its limiting integrable variant called the Hénon problem, for which the original Hill's problem is a singular perturbation. Among solutions to the Hénon problem there are a countable number of generating solutions-arcs that are uniquely determined by the condition of successive passage through the origin of coordinates—singular point of equations of motion of the Hill's problem. Using the generating solutions-arcs as "letters" of a certain "alphabet", one can compose, according to some rules, the "words": generating solutions of families of periodic orbits of the Hill's problem. The sequence of letters in a word determines the order of orbit transfer from one invariant manifold to another, while the set of all properly specified words determine the system's symbolic dynamics.

  17. VIEW OF SURGE TANK AND TRANSFORMER YARD FROM HILL ABOVE ...

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

    VIEW OF SURGE TANK AND TRANSFORMER YARD FROM HILL ABOVE POWERHOUSE. PHOTO BY JET LOWE, HAER, 1995. - Elwha River Hydroelectric System, Glines Hydroelectric Dam & Plant, Port Angeles, Clallam County, WA

  18. TRANSMISSION TOWERS WITH LIGHTENING ARRESTORS ON HILL NORTH OF ELWHA ...

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

    TRANSMISSION TOWERS WITH LIGHTENING ARRESTORS ON HILL NORTH OF ELWHA POWERHOUSE. PHOTO BY JET LOWE, HAER, 1995. - Elwha River Hydroelectric System, Elwha Hydroelectric Dam & Plant, Port Angeles, Clallam County, WA

  19. 28. VIEW OF BRIDGE, LOOKING WEST FROM CREST OF HILL ...

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

    28. VIEW OF BRIDGE, LOOKING WEST FROM CREST OF HILL ABOVE EAST TOWER. NOTE SWAY CABLES ON EACH SIDE OF THE WALKWAY. March 1987 - Verde River Sheep Bridge, Spanning Verde River (Tonto National Forest), Cave Creek, Maricopa County, AZ

  20. 24. VIEW FORM NORTHWEST, WHERE HOUSE RECEDES INTO HILL, SHOWING ...

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

    24. VIEW FORM NORTHWEST, WHERE HOUSE RECEDES INTO HILL, SHOWING ROOF, CHIMNEY AND OCTAGONAL SKYLIGHT TO KITCHEN IN CENTER - Isaac N. Hagan House, Kentuck Knob, U.S. Route 40 vicinity (Stewart Township), Chalkhill, Fayette County, PA

  1. 3. Historic American Buildings Survey Joseph Hill, Photographer August 1936 ...

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

    3. Historic American Buildings Survey Joseph Hill, Photographer August 1936 BRONZE TABLET HISTORICAL MARKER - Hobson Grist Mill (Monument & Millstones), DuPage County Pioneer Park, Naperville, Du Page County, IL

  2. Directional Site Amplification Effect on Tarzana Hill, California

    NASA Astrophysics Data System (ADS)

    Graizer, V.; Shakal, A.

    2003-12-01

    Significantly amplified ground accelerations at the Tarzana Hill station were recorded during the 1987 Mw 5.9 Whittier Narrows and the 1994 Mw 6.7 Northridge earthquakes. Peak horizontal ground acceleration at the Tarzana station during the 1999 Mw 7.1 Hector Mine earthquake was almost twice as large as the accelerations recorded at nearby stations. The Tarzana site was drilled to a depth of 100 m. A low shear-wave velocity near the surface of 100 m/sec increasing to near 750 m/sec at 100 m depth was measured. The 20 m high hill was found to be well drained with a water table near 17 m. Modelo formation (extremely weathered at the surface to fresh at depth) underlies the hill. The subsurface geology and velocities obtained allow classification of this location as a soft-rock site. After the Northridge earthquake the California Strong Motion Instrumentation Program significantly increased instrumentation at Tarzana to study the unusual site amplification effect. Current instrumentation at Tarzana consists of an accelerograph at the top of Tarzana hill (Tarzana - Cedar Hill B), a downhole instrument at 60 m depth, and an accelerograph at the foot of the hill (Tarzana - Clubhouse), 180 m from the Cedar Hill B station. The original station, Tarzana - Cedar Hill Nursery A, was lost in 1999 due to construction. More than twenty events, including the Hector Mine earthquake, were recorded by all these instruments at Tarzana. Comparison of recordings and response spectra demonstrates strong directional resonance on the top of the hill in a direction perpendicular to the strike of the hill in the period range from 0.04 to 0.8 sec (1.2 to 25 Hz). There is practically no amplification from the bottom to the top of the hill for the component parallel to the strike of the hill. In contrast to accelerations recorded during the Hector Mine earthquake (high frequency part of seismic signal), displacements (relatively low frequency part of seismic signal) demonstrate almost no site

  3. 220. Dennis Hill, Photographer July 1998 ELEVATION VIEW OF WEST ...

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

    220. Dennis Hill, Photographer July 1998 ELEVATION VIEW OF WEST TUNNEL PORTAL, FACING NORTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  4. 139. Dennis Hill, Photographer January 1998 ELEVATION VIEW OF TRANSBAY ...

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

    139. Dennis Hill, Photographer January 1998 ELEVATION VIEW OF TRANSBAY TERMINAL BUS LOOP CROSSING OVER HARRISON STREET, FACING NORTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  5. 97. Dennis Hill, Photographer December 1997 VIEW OF ELEVATION AND ...

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

    97. Dennis Hill, Photographer December 1997 VIEW OF ELEVATION AND UNDERSIDE OF SAN FRANCISCO VIADUCT BETWEEN FIFTH AND FOURTH STREETS, FACING SOUTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  6. 179. Dennis Hill, Photographer June 1998 AERIAL ELEVATION VIEW OF ...

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

    179. Dennis Hill, Photographer June 1998 AERIAL ELEVATION VIEW OF SUSPENSION BRIDGE STIFFENING TRUSS AND TOWER W-2, FACING NORTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  7. 322. Dennis Hill, Photographer May 1998 VIEW OF GIRDER SPANS, ...

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

    322. Dennis Hill, Photographer May 1998 VIEW OF GIRDER SPANS, OAKLAND APPROACH AT TRANSITION TO DOUBLE-DECK ROADWAY, FACING WEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  8. 12. Historic American Buildings Survey Joseph Hill, Photographer July 10, ...

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

    12. Historic American Buildings Survey Joseph Hill, Photographer July 10, 1936 SOUTH ELEVATION (Copied from student's drawing, Dept. of Architecture, Armour Institute of Technology. Chicago) - Keating House, U.S. Highway 430, Fayville, Alexander County, IL

  9. 1. Historic American Buildings Survey Joseph Hill, Photographer Oct. 25, ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer Oct. 25, 1936 #1 MAXIENER HOUSE 104 South Bench Street Galena, Illinois - Galena Doorways, Elizabeth Maxiener Cottage, 104 South Bench Street, Galena, Jo Daviess County, IL

  10. 1. Historic American Buildings Survey Joseph Hill, Photographer 1936 #4 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer 1936 #4 FORMERLY SISTERS OF MERCY CONVENT 226 North Bench Street, Galena, Illinois. - Galena Doorways, Sisters of Mercy Convent, 226 North Bench Street, Galena, Jo Daviess County, IL

  11. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #2 PORTER HOUSE, 110 Bench St. Galena, Illinois - Galena Doorways, Porter House, 110 North Bench Street, Galena, Jo Daviess County, IL

  12. 1. Historic American Buildings Survey Copied by Joseph Hill from ...

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

    1. Historic American Buildings Survey Copied by Joseph Hill from an old photograph loaned by Alice Snyder, Galena, Illinois. SOUTH EAST ELEVATION - Grace Episcopal Church, South Prospect Street, Galena, Jo Daviess County, IL

  13. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #5 GRIMM HOUSE 608 South Bench Street, Galena. - Galena Doorways, Heike Grimm House, 608 South Bench Street, Galena, Jo Daviess County, IL

  14. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #7 KLINGEL HOUSE ON BENCH STREET Galena, Illinois - Galena Doorways, Peter Klingel House, Bench Street, Galena, Jo Daviess County, IL

  15. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #3 HEMPSTEAD HOUSE (about 1846) 611 South Bench Street, Galena, Ill. - Galena Doorways, Charles Hempstead House, 611 South Bench Street, Galena, Jo Daviess County, IL

  16. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #13 EARLY WAREHOUSE South Main Street, South of Booth, Galena, Illinois - Galena Doorways, Warehouse, South Main Street, Galena, Jo Daviess County, IL

  17. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #6 CALDERWOOD HOUSE (1839) North Bench Street, Galena, Ill. - Celia Calderwood House, North Bench Street, Galena, Jo Daviess County, IL

  18. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #8 STAIR RAILING TELFORD SHOP Bench Street, Galena, Ill. - Galena Doorways, Telford Shop, Bench Street, Galena, Jo Daviess County, IL

  19. 1. Historic American Buildings Survey Joseph Hill, Photographer October 25, ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 25, 1936 #9 HARMONY LODGE ON BENCH STREET (1858) - Galena Doorways, Harmony Lodge of Odd Fellows, Bench Street, Galena, Jo Daviess County, IL

  20. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #10 Early Methodist Church, Later Odd Fellows Lodge on Bench Street. - Galena Doorways, First Methodist Church, Bench Street, Galena, Jo Daviess County, IL

  1. 1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer October 1936 #16 OLD DOWLING HOUSE (Broadway), Galena - Galena Doorways, John Dowling House, Main & Diagonal Streets, Galena, Jo Daviess County, IL

  2. 18. Historic American Buildings Survey Joseph Hill, Photographer May 26, ...

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

    18. Historic American Buildings Survey Joseph Hill, Photographer May 26, 1936 FIREPLACE IN DINING ROOM, The Davenport House, Rock Island Arsenal - Rock Island Arsenal, Building No. 346, Davenport Drive, Arsenal Grounds, Rock Island, Rock Island County, IL

  3. 1. Historic American Buildings Survey Joseph Hill, Photographer July 1936 ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer July 1936 STAIR RAILING, 66 WEST OAK STREET - Chicago Ironwork, 66 West Oak Street (Cast Iron Stair Railing), 66 West Oak Street, Chicago, Cook County, IL

  4. 2. Historic American Buildings Survey Joseph Hill, Photographer July 1936 ...

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

    2. Historic American Buildings Survey Joseph Hill, Photographer July 1936 BALCONY RAILING, 945 NO. DEARBORN ST. JUDGE CARPENTER'S HOME - Chicago Ironwork, Judge Carpenter House (Cast Iron Balcony Railing), 945 North Dearborn Street, Chicago, Cook County, IL

  5. 3. Historic American Buildings Survey Joseph Hill, Photographer June, 1936 ...

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

    3. Historic American Buildings Survey Joseph Hill, Photographer June, 1936 DETAIL OF BALCONY RAILING, 945 NO. DEARBORN ST. JUDGE CARPENTER'S HOME - Chicago Ironwork, Judge Carpenter House (Cast Iron Balcony Railing), 945 North Dearborn Street, Chicago, Cook County, IL

  6. 170. Credit SHS. Northern California Power Company substation, Bully Hill ...

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

    170. Credit SHS. Northern California Power Company substation, Bully Hill Mine area. Note lack of vegetation, caused by nearby copper smelting works. - Battle Creek Hydroelectric System, Battle Creek & Tributaries, Red Bluff, Tehama County, CA

  7. 184. Dennis Hill, Photographer June 1998 DETAIL VIEW OF UPPER ...

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

    184. Dennis Hill, Photographer June 1998 DETAIL VIEW OF UPPER DECK EXPANSION JOINT AT PIER W-2, FACING WEST-SOUTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  8. 258. Dennis Hill, Photographer April 1998 VIEW OF CANTILEVER TRUSS ...

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

    258. Dennis Hill, Photographer April 1998 VIEW OF CANTILEVER TRUSS ANCHOR ARM AT PIERS E- AND E-2, SOUTH SIDE, FACING NORTH. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  9. 12. VIEW FROM PARKWAY MEDIAN TO SPORT HILL ROAD BRIDGE, ...

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

    12. VIEW FROM PARKWAY MEDIAN TO SPORT HILL ROAD BRIDGE, Copy of photograph ca. 1940. Collection Connecticut Department of Transportation. - Merritt Parkway, Bridge No. 744, Spanning Merritt Parkway at Route 59, Fairfield, Fairfield County, CT

  10. 9. Landscape overview east to El Dorado Hills; ditch follows ...

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

    9. Landscape overview east to El Dorado Hills; ditch follows fence line in middle distance - Natomas Ditch System, Blue Ravine Segment, Juncture of Blue Ravine & Green Valley Roads, Folsom, Sacramento County, CA

  11. 308. Dennis Hill, Photographer April 1998 VIEW OF DECK TRUSS ...

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

    308. Dennis Hill, Photographer April 1998 VIEW OF DECK TRUSS SPANS WITH THROUGH TRUSS SPANS AND CANTILEVER TRUSS IN BACKGROUND, SOUTH SIDE, FACING WEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  12. 22. TRANSMISSION MAIN, PLAN AND PROFILE, INDEX SHEET. Leeds, Hill, ...

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

    22. TRANSMISSION MAIN, PLAN AND PROFILE, INDEX SHEET. Leeds, Hill, Barnard & Jewett drawing, no date, no number. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA

  13. 123. Dennis Hill, Photographer January 1998 VIEW OF UPPER DECK ...

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

    123. Dennis Hill, Photographer January 1998 VIEW OF UPPER DECK OFF-RAMP DESCENDING TO FREMONT STREET, WITH TRANSBAY TERMINAL BUS LOOP BEHIND, FACING NORTH. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  14. 5. View to the north from hill, just after Minnesota ...

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

    5. View to the north from hill, just after Minnesota Monument; Bust of general Issac F. Quinby on Union Avenue, 3-inch ordnance rifle on left. - Vicksburg National Military Park Roads & Bridges, Vicksburg, Warren County, MS

  15. Multiwalled ice helixes and ice nanotubes

    PubMed Central

    Bai, Jaeil; Wang, Jun; Zeng, X. C.

    2006-01-01

    We report six phases of high-density nano-ice predicted to form within carbon nanotubes (CNTs) at high pressure. High-density nano-ice self-assembled within smaller-diameter CNT (17,0) exhibits a double-walled helical structure where the outer wall consists of four double-stranded helixes, which resemble a DNA double helix, and the inner wall is a quadruple-stranded helix. Four other double-walled nano-ices, self-assembled respectively in two larger-diameter CNTs (20,0 and 22,0), display tubular structure. Within CNT (24,0), the confined water can freeze spontaneously into a triple-walled helical nano-ice where the outer wall is an 18-stranded helix and the middle and inner walls are hextuple-stranded helixes. PMID:17170136

  16. Blue-ice moraines in Antarctica: long-term formation and short-term change

    NASA Astrophysics Data System (ADS)

    Woodward, J.; Dunning, S.; Sugden, D.; Hein, A.; Marrero, S.

    2013-12-01

    The Heritage Range at the southern end of the Ellsworth Mountains lies across the main flow of the West Antarctic Ice Sheet (WAIS) just 50 km from the grounding line of the Filchner-Ronne Ice Shelf. If the long-term record of ice sheet change can be understood from the Blue Ice Moraines (BIM) found along the hills it becomes a critical location to understand the past behaviour of the ice sheet, and therefore, to better understand the future behaviour of WAIS in a warming climate. We present integrated geophysical data from Unmanned Aerial Vehicles (UAV), Terrestrial Laser Scanning (TLS) and ground penetrating radar (GPR) that helps us understand the long-term formation, and short-term mophological changes of BIMs. BIMs along the front of Patriot Hills (part of the Heritage Range) are associated with katabatic winds enhancing ablation and sublimation to create depressions that are then compensated for by ice-flow from the main trunk glacier at right angles to the main flow direction. This ice flow brings basal debris from the trunk glacier that can reside for long-periods of time rather than being removed by the dominant mountain parallel ice-flow. Using GPR we have imaged debris bands from the trunk glacier arriving directly into the lowest BIMs, and also emerging at the ice surface as folded debris bands in the moraine-marginal depressions that do not have a dense enough debris cover to prevent ablation. High resolution elevation models derived from TLS, and a UAV quantify the changing topography associated with this debris arriving into the BIM, and the surface change over a summer melt season. This work was funded by NERC Standard Grant NE/I025840/1

  17. Landscape formation by past continental ice sheets: insights into the subglacial environment

    NASA Astrophysics Data System (ADS)

    Piotrowski, Jan A.

    2014-05-01

    Glaciers and ice sheets are known as most powerful, climatically driven agents of large-scale sediment redistribution and landscape formation in the Earth system. During the Quaternary, repeated waxing and waning of continental ice sheets contributed to profound reshaping of the Earth surface and set the scene for the development of ecosystems in the post-glacial time. Despite the well-established impact of glaciers on the upper lithosphere the specific processes of glacial erosion, transport and deposition and the formation landforms at the ice-bed interface are contentious. In particular, the relative importance of direct ice impact versus the impact of glacial meltwater is highly controversial. Here, we focus on the southern peripheral area of the Scandinavian Ice Sheet hosting thick successions of soft, deformable sediments and examine some spectacular sediment/landform assemblages found nowadays in both terrestrial and marine settings to illustrate the nature of the subglacial processes. In order to decipher the past ice sheet behavior field, experimental and numerical approaches are combined. It is shown that the strength of the coupling between the ice and the bed that controls the response of the substratum to ice overriding and stress propagation depends primarily on the ability of the glacial system to evacuate meltwater from ice-bed interface. Strong coupling, locally enhanced by subglacial permafrost resulted in deeply rooted (100's of meters) glaciotectonic deformation reflected on the surface as ice-shoved hills whereas weak coupling promoted by water accumulating under the ice triggered the formation of deep (100's of meters) tunnel valley networks. Under the arteries of fast-flowing ice known as palaeo-ice streams, remoulding of soft sediments generated mega-scale glacial lineations and drumlins that hold the key to understanding glacier dynamics. The subglacial environment is envisaged as a four-dimensional mosaic of stable and deforming spots

  18. After runaway: The trans-Hill stage of planetesimal growth

    SciTech Connect

    Lithwick, Yoram

    2014-01-01

    When planetesimals begin to grow by coagulation, they first enter an epoch of runaway, during which the biggest bodies grow faster than all the others. The questions of how runaway ends and what comes next have not been answered satisfactorily. We show that runaway is followed by a new stage—the 'trans-Hill stage'—that commences when the bodies that dominate viscous stirring ('big bodies') become trans-Hill, i.e., when their Hill velocity matches the random speed of the small bodies they accrete. Subsequently, the small bodies' random speed grows in lockstep with the big bodies' sizes, such that the system remains in the trans-Hill state. Trans-Hill growth is crucial for determining the efficiency of growing big bodies, as well as their growth timescale and size spectrum. Trans-Hill growth has two sub-stages. In the earlier one, which occurs while the stirring bodies remain sufficiently small, the evolution is collisionless, i.e., collisional cooling among all bodies is irrelevant. The efficiency of forming big bodies in this collisionless sub-stage is very low, ∼10α << 1, where α ∼ 0.005(a/AU){sup –1} is the ratio between the physical size of a body and its Hill radius. Furthermore, the size spectrum is flat (equal mass per size decade, i.e., q = 4). This collisionless trans-Hill solution explains results from previous coagulation simulations for both the Kuiper Belt and the asteroid belt. The second trans-Hill sub-stage commences once the stirring bodies grow big enough (>α{sup –1} × the size of the accreted small bodies). After that time, collisional cooling among small bodies controls the evolution. The efficiency of forming big bodies rises and the size spectrum becomes more top heavy. Trans-Hill growth can terminate in one of two ways, depending on the sizes of the small bodies. First, mutual accretion of big bodies can become significant and conglomeration proceeds until half of the total mass is converted into big bodies. This mode of growth

  19. Ethnobiology of the Nilgiri hills, India.

    PubMed

    Rajan, S; Sethuraman, M; Mukherjee, Pulok K

    2002-03-01

    The Nilgiri is a popular massif towering high in the Western Ghats in South India with an altitude of 2623 m. Nature has been magnanimous in bestowing Nilgiri district with rich evergreen temperate to tropical forests. A high degree of biodiversity, marked by varied flora and fauna of good therapeutic potential as well as the varied number of indigenous groups of people in this area, makes it very popular among herbalists. The district has six anthropologically well defined ethnic groups namely Todas, Kotas, Kurumbas, Irulas, Paniyas and Kattunayakas living here possibly since 1200 B.C. The present review highlights the ethnobiological profile of six indigenous populations and their dependence on ambient flora and fauna for traditional health care needs. It has been observed that about 2700 therapeutically potent plant species are available in this hill station of which almost all have come from local medicine. Some have been explored scientifically. However, about 150 plant species are still to be explored for their therapeutic potential. The ethnography, phytochemical and therapeutic uses as well as the anthropological perspectives of the local medicines have been discussed in this review. PMID:11933110

  20. SRTM Anaglyph: Haro and Kas Hills

    NASA Technical Reports Server (NTRS)

    2001-01-01

    On January 26, 2001 the Kachchh region in western India suffered the most deadly earthquake in India's history. This three-dimensional view of landforms northeast of the city of Bhuj depicts geologic structures that are of interest in the study the tectonic processes that may have led to that earthquake. However, preliminary field studies indicate that these structures are composed of Mesozoic rocks that are overlain by younger rocks showing little deformation. Thus these structures may be old, not actively growing, and not directly related to the recent earthquake.

    The Haro Hills are on the left and the Kas Hills are on the right. The Haro Hills are an 'anticline,' which is an upwardly convex elongated fold of layered rocks. The anticline is distinctly ringed by an erosion resistant layer of sandstone. The east-west orientation of the anticline may relate to the crustal compression that has occurred during India's northward movement toward, and collision with, Asia. In contrast, the largest of the Kas Hills appears to be a tilted (to the south) and faulted (on the north) block of layered rocks. Also seen here, the curvilinear ridge trending toward the southwest from the image center is an erosion resistant 'dike,' which is an igneous intrusion into older 'host' rocks along a fault plane or other crack. The dike also appears to extend northeast from the image center as a dark line having very little topography. Its location between the tilted block and a smaller anticline to the north (directly east of the larger anticline) probably indicates that the dike fills the fault that separates these contrasting geologic structures. These features are simple examples of how digital elevation data can stereoscopically enhance satellite imagery to provide a direct input to geologic studies.

    The stereoscopic effect of this anaglyph was created by first draping a Landsat satellite image (taken just two weeks after the earthquake) over preliminary digital elevation

  1. Bunker Hill Superfund site: Ecological restoration program

    SciTech Connect

    Brown, S.; Chaney, R.; Henry, C.L.; Compton, H.

    1998-12-31

    Bunker Hill ID was the site of mining and smelting activities for many decades. As a result of these activities, soils on the hillsides adjacent to the site became contaminated with Pb, Zn, and Cd. In addition to metal contamination, pH of the soils became highly acidic. Native vegetation has died off and the soils have become highly erosive. An application of municipal biosolids in combination with wood ash and log yard wood waste was made to test the potential of this remediation mixture to reduce erosion, correct soil pH, and support a self sustaining vegetative cover. Biosolids improve soil physical properties and provide macro and micro nutrients. Wood ash serves as a lime substitute and a source of nutrients. Log yard waste improves physical properties and has a high C:N ratio that reduces the potential for N leaching. Initial results are promising. A healthy stand of grasses and legumes has been established. In addition, the application mixture has proven itself to be highly resistant to erosion.

  2. Robert I. Hill (1953-1992)

    NASA Astrophysics Data System (ADS)

    Davies, Geoff

    Robert I. Hill of the Research School of Earth Sciences, Australian National University, died suddenly on July 25 at age 38. Robert was a warm and generous person, a scientist with substantial accomplishments already to his credit, and a skilled lobbyist for and communicator of science. He had great potential as a scientist and as a leader of science.Robert obtained a first-class honors degree from the ANU Geology Department in 1976 and a Ph.D. from Caltech in 1984. He went on to become a research associate at Cambridge, a research fellow at RSES, and finally, a Queen Elizabeth II Fellow there. His Ph.D. research was a field-based study of the dynamic processes involved in the intrusion of magma into the crust. Later, he studied the sources of deep crustal fluids using helium isotopes, the geological setting of ore bodies with a variety of geochemical and geochronological methods, the occurrence of oil and gas deposits, and the processes that formed and modified the continental crust.

  3. Steamboat Hills exploratory slimhole: Drilling and testing

    SciTech Connect

    Finger, J.T.; Jacobson, F.D.; Hickox, C.E.; Eaton, R.R.

    1994-10-01

    During July-September, 1993, Sandia National Laboratories, in cooperation with Far West Capital, drilled a 4000 feet exploratory slimhole (3.9 inch diameter) in the Steamboat Hills geothermal field near Reno, Nevada. This well was part of Sandia`s program to evaluate slimholes as a geothermal exploration tool. During and after drilling the authors performed four series of production and injection tests while taking downhole (pressure-temperature-spinner) and surface (wellhead pressure and temperature, flow rate) data. In addition to these measurements, the well`s data set includes: continuous core (with detailed log); borehole televiewer images of the wellbore`s upper 500 feet; daily drilling reports from Sandia and from drilling contractor personnel; daily drilling fluid record; numerous temperature logs; and comparative data from production and injection wells in the same field. This report contains: (1) a narrative account of the drilling and testing, (2) a description of equipment used, (3) a brief geologic description of the formation drilled, (4) a summary and preliminary interpretation of the data, and (5) recommendations for future work.

  4. Preparing and Analyzing Iced Airfoils

    NASA Technical Reports Server (NTRS)

    Vickerman, Mary B.; Baez, Marivell; Braun, Donald C.; Cotton, Barbara J.; Choo, Yung K.; Coroneos, Rula M.; Pennline, James A.; Hackenberg, Anthony W.; Schilling, Herbert W.; Slater, John W.; Burke, Kevin M.; Nolan, Gerald J.; Brown, Dennis

    2004-01-01

    SmaggIce version 1.2 is a computer program for preparing and analyzing iced airfoils. It includes interactive tools for (1) measuring ice-shape characteristics, (2) controlled smoothing of ice shapes, (3) curve discretization, (4) generation of artificial ice shapes, and (5) detection and correction of input errors. Measurements of ice shapes are essential for establishing relationships between characteristics of ice and effects of ice on airfoil performance. The shape-smoothing tool helps prepare ice shapes for use with already available grid-generation and computational-fluid-dynamics software for studying the aerodynamic effects of smoothed ice on airfoils. The artificial ice-shape generation tool supports parametric studies since ice-shape parameters can easily be controlled with the artificial ice. In such studies, artificial shapes generated by this program can supplement simulated ice obtained from icing research tunnels and real ice obtained from flight test under icing weather condition. SmaggIce also automatically detects geometry errors such as tangles or duplicate points in the boundary which may be introduced by digitization and provides tools to correct these. By use of interactive tools included in SmaggIce version 1.2, one can easily characterize ice shapes and prepare iced airfoils for grid generation and flow simulations.

  5. SOUTH ELEVATION OF GOLD HILL MILL, LOOKING NORTH. THE PRIMARY ...

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

    SOUTH ELEVATION OF GOLD HILL MILL, LOOKING NORTH. THE PRIMARY ORE BIN IS A CENTER, WITH A JAW CRUSHER JUST TO THE RIGHT. A CONVEYOR (MISSING) WAS USED TO CARRY CRUSHED ORE UP AND INTO THE SECONDARY ORE BIN. THE STONE RAMP TO THE LEFT OF THE ORE BIN WAS USED TO DRIVE TRUCKS UP TO DUMPING LEVEL. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  6. 2. General view of Fort Hill Farm, view looking north ...

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

    2. General view of Fort Hill Farm, view looking north from (F) two-room cabin. From left to right, buildings visible are (I) log tobacco barn; (H and D) shed and center chimney four-room cabin; (E and (A) one-room cabin in front of mansion; (J) hay barn. - Fort Hill Farm, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  7. 1. General view of Fort Hill Farm, view looking southsoutheast. ...

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

    1. General view of Fort Hill Farm, view looking south-southeast. From left to right, buildings visible are (B) two-story hall-and-parlor house; (k) small barn; (A) mansion' (G( shed; (H) shed; (I) log tobacco barn; (H and D) shed and center chimney four-room cabin; (E and (A) one-room cabin in front of mansion; (J) hay barn. - Fort Hill Farm, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  8. 3. General view of Fort Hill Farm, view looking west ...

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

    3. General view of Fort Hill Farm, view looking west from (B) two-story hall-and-parlor house. Buildings visible, from left to right, are (B) parlor house porch; (E) one-room cabin; (D) center chimney four-room cabin; (J) hay barn; (I) log tobacco barn; (A) mansion, obscured by trees; (M) stable; (K) small barn. - Fort Hill Farm, West of Staunton (Roanoke) River between Turkey & Caesar's Runs, Clover, Halifax County, VA

  9. 4. BUNKER HILL LEAD SMELTER. VIEW IS FROM RIDGE ABOVE ...

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

    4. BUNKER HILL LEAD SMELTER. VIEW IS FROM RIDGE ABOVE GOVERNMENT GULCH LOOKING TO THE EAST. IN THE RIGHT MID GROUND, CARPENTER SHOP BUILDINGS AND FRAMING SHEDS ARE VISIBLE. THE BACKGROUND FACILITIES VISIBLE FROM L. TO R. ARE: SMELTER OFFICE, REFINERIES, SLAG FUMING STACKS, HIGH VELOCITY FLUE, BAG HOUSE, 200-FOOT STACK, AND 715-FOOT STACK. - Bunker Hill Lead Smelter, Bradley Rail Siding, Kellogg, Shoshone County, ID

  10. Prospecting for Martian Ice

    NASA Technical Reports Server (NTRS)

    McBride, S. A.; Allen, C. C.; Bell, M. S.

    2005-01-01

    During high Martian obliquity, ice is stable to lower latitudes than predicted by models of present conditions and observed by the Gamma Ray Spectrometer (approx. 60 deg N). An ice-rich layer deposited at mid-latitudes could persist to the present day; ablation of the top 1 m of ice leaving a thin insulating cover could account for lack of its detection by GRS. The presence of an ice-layer in the mid-latitudes is suggested by a network of polygons, interpreted as ice-wedge cracks. This study focuses on an exceptional concentration of polygons in Western Utopia (section of Casius quadrangle, roughly 40 deg - 50 deg N, 255 deg - 300 deg W). We attempt to determine the thickness and age of this ice layer through crater-polygons relations.

  11. Ice-Nucleating Bacteria

    NASA Astrophysics Data System (ADS)

    Obata, Hitoshi

    Since the discovery of ice-nucleating bacteria in 1974 by Maki et al., a large number of studies on the biological characteristics, ice-nucleating substance, ice nucleation gene and frost damage etc. of the bacteria have been carried out. Ice-nucleating bacteria can cause the freezing of water at relatively warm temperature (-2.3°C). Tween 20 was good substrates for ice-nucleating activity of Pseudomonas fluorescens KUIN-1. Major fatty acids of Isolate (Pseudomonas fluorescens) W-11 grown at 30°C were palmitic, cis-9-hexadecenoic and cis-11-octadecenoic which amounted to 90% of the total fatty acids. Sequence analysis shows that an ice nucleation gene from Pseudomonas fluorescens is related to the gene of Pseudomonas syringae.

  12. Naled ice growth

    NASA Astrophysics Data System (ADS)

    Schohl, G. A.; Ettema, R.

    1986-02-01

    Based on theoretical formulation and dimensional analysis, supported by the results of laboratory experiments, a theory and a detailed description of naled ice growth are presented. The theory, concepts, and data should be of interest to engineers concerned with the effects of naleds (also referred to as aufeis or icings) on engineering works. The growth of a two dimensional, or laterally confined (flume), naled is shown to depend primarily on seven, independent, dimensionless parameters. The early, two dimensional, phase of growth, a naled consists of a mixture of ice and water, or ice-water slush, forming on a frigid base. The influence of two of the three remaining parameters is not felt until after a transition time has passed. The continuing, cyclic process by which slush layers form and eventually freeze results in the ice laminations that are a feature of naled ice.

  13. Producing desired ice faces

    PubMed Central

    Shultz, Mary Jane; Brumberg, Alexandra; Bisson, Patrick J.; Shultz, Ryan

    2015-01-01

    The ability to prepare single-crystal faces has become central to developing and testing models for chemistry at interfaces, spectacularly demonstrated by heterogeneous catalysis and nanoscience. This ability has been hampered for hexagonal ice, Ih––a fundamental hydrogen-bonded surface––due to two characteristics of ice: ice does not readily cleave along a crystal lattice plane and properties of ice grown on a substrate can differ significantly from those of neat ice. This work describes laboratory-based methods both to determine the Ih crystal lattice orientation relative to a surface and to use that orientation to prepare any desired face. The work builds on previous results attaining nearly 100% yield of high-quality, single-crystal boules. With these methods, researchers can prepare authentic, single-crystal ice surfaces for numerous studies including uptake measurements, surface reactivity, and catalytic activity of this ubiquitous, fundamental solid. PMID:26512102

  14. An ice lithography instrument

    NASA Astrophysics Data System (ADS)

    Han, Anpan; Chervinsky, John; Branton, Daniel; Golovchenko, J. A.

    2011-06-01

    We describe the design of an instrument that can fully implement a new nanopatterning method called ice lithography, where ice is used as the resist. Water vapor is introduced into a scanning electron microscope (SEM) vacuum chamber above a sample cooled down to 110 K. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice is removed by the SEM electron beam (e-beam) guided by an e-beam lithography system. Without breaking vacuum, the sample with the ice mask is then transferred into a metal deposition chamber where metals are deposited by sputtering. The cold sample is then unloaded from the vacuum system and immersed in isopropanol at room temperature. As the ice melts, metal deposited on the ice disperses while the metals deposited on the sample where the ice had been removed by the e-beam remains. The instrument combines a high beam-current thermal field emission SEM fitted with an e-beam lithography system, cryogenic systems, and a high vacuum metal deposition system in a design that optimizes ice lithography for high throughput nanodevice fabrication. The nanoscale capability of the instrument is demonstrated with the fabrication of nanoscale metal lines.

  15. Ice age paleotopography

    SciTech Connect

    Peltier, W.R. )

    1994-07-08

    A gravitationally self-consistent theory of postglacial relative sea level change is used to infer the variation of surface ice and water cover since the Last Glacial Maximum (LGM). The results show that LGM ice volume was approximately 35 percent lower than suggested by the CLIMAP reconstruction and the maximum heights of the main Laurentian and Fennoscandian ice complexes are inferred to have been commensurately lower with respect to sea level. Use of these Ice Age boundary conditions in atmospheric general circulation models will yield climates that differ significantly from those previously inferred on the basis of the CLIMAP data set.

  16. An ice lithography instrument

    SciTech Connect

    Han, Anpan; Chervinsky, John; Branton, Daniel; Golovchenko, J. A.

    2011-06-15

    We describe the design of an instrument that can fully implement a new nanopatterning method called ice lithography, where ice is used as the resist. Water vapor is introduced into a scanning electron microscope (SEM) vacuum chamber above a sample cooled down to 110 K. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice is removed by the SEM electron beam (e-beam) guided by an e-beam lithography system. Without breaking vacuum, the sample with the ice mask is then transferred into a metal deposition chamber where metals are deposited by sputtering. The cold sample is then unloaded from the vacuum system and immersed in isopropanol at room temperature. As the ice melts, metal deposited on the ice disperses while the metals deposited on the sample where the ice had been removed by the e-beam remains. The instrument combines a high beam-current thermal field emission SEM fitted with an e-beam lithography system, cryogenic systems, and a high vacuum metal deposition system in a design that optimizes ice lithography for high throughput nanodevice fabrication. The nanoscale capability of the instrument is demonstrated with the fabrication of nanoscale metal lines.

  17. An ice lithography instrument.

    PubMed

    Han, Anpan; Chervinsky, John; Branton, Daniel; Golovchenko, J A

    2011-06-01

    We describe the design of an instrument that can fully implement a new nanopatterning method called ice lithography, where ice is used as the resist. Water vapor is introduced into a scanning electron microscope (SEM) vacuum chamber above a sample cooled down to 110 K. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice is removed by the SEM electron beam (e-beam) guided by an e-beam lithography system. Without breaking vacuum, the sample with the ice mask is then transferred into a metal deposition chamber where metals are deposited by sputtering. The cold sample is then unloaded from the vacuum system and immersed in isopropanol at room temperature. As the ice melts, metal deposited on the ice disperses while the metals deposited on the sample where the ice had been removed by the e-beam remains. The instrument combines a high beam-current thermal field emission SEM fitted with an e-beam lithography system, cryogenic systems, and a high vacuum metal deposition system in a design that optimizes ice lithography for high throughput nanodevice fabrication. The nanoscale capability of the instrument is demonstrated with the fabrication of nanoscale metal lines. PMID:21721733

  18. Ice barrier construction

    SciTech Connect

    Finucane, R. G.; Jahns, H. O.

    1985-06-18

    A method is provided for constructing spray ice barriers to protect offshore structures in a frigid body of water from mobile ice, waves and currents. Water is withdrawn from the body of water and is sprayed through ambient air which is below the freezing temperature of the water so that a substantial amount of the water freezes as it passes through the air. The sprayed water is directed to build up a mass of ice having a size and shape adapted to protect the offshore structure. Spray ice barriers can also be constructed for the containment of pollutant spills.

  19. An ice lithography instrument

    PubMed Central

    Han, Anpan; Chervinsky, John; Branton, Daniel; Golovchenko, J. A.

    2011-01-01

    We describe the design of an instrument that can fully implement a new nanopatterning method called ice lithography, where ice is used as the resist. Water vapor is introduced into a scanning electron microscope (SEM) vacuum chamber above a sample cooled down to 110 K. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice is removed by the SEM electron beam (e-beam) guided by an e-beam lithography system. Without breaking vacuum, the sample with the ice mask is then transferred into a metal deposition chamber where metals are deposited by sputtering. The cold sample is then unloaded from the vacuum system and immersed in isopropanol at room temperature. As the ice melts, metal deposited on the ice disperses while the metals deposited on the sample where the ice had been removed by the e-beam remains. The instrument combines a high beam-current thermal field emission SEM fitted with an e-beam lithography system, cryogenic systems, and a high vacuum metal deposition system in a design that optimizes ice lithography for high throughput nanodevice fabrication. The nanoscale capability of the instrument is demonstrated with the fabrication of nanoscale metal lines. PMID:21721733

  20. Stargazing at 'Husband Hill Observatory' on Mars

    NASA Technical Reports Server (NTRS)

    2005-01-01

    NASA's Mars Exploration Rover Spirit continues to take advantage of extra solar energy by occasionally turning its cameras upward for night sky observations. Most recently, Spirit made a series of observations of bright star fields from the summit of 'Husband Hill' in Gusev Crater on Mars. Scientists use the images to assess the cameras' sensitivity and to search for evidence of nighttime clouds or haze. The image on the left is a computer simulation of the stars in the constellation Orion. The next three images are actual views of Orion captured with Spirit's panoramic camera during exposures of 10, 30, and 60 seconds.

    Because Spirit is in the southern hemisphere of Mars, Orion appears upside down compared to how it would appear to viewers in the Northern Hemisphere of Earth. 'Star trails' in the longer exposures are a result of the planet's rotation. The faintest stars visible in the 60-second exposure are about as bright as the faintest stars visible with the naked eye from Earth (about magnitude 6 in astronomical terms). The Orion Nebula, famous as a nursery of newly forming stars, is also visible in these images. Bright streaks in some parts of the images aren't stars or meteors or unidentified flying objects, but are caused by solar and galactic cosmic rays striking the camera's detector. Spirit acquired these images with the panoramic camera on Martian day, or sol, 632 (Oct. 13, 2005) at around 45 minutes past midnight local time, using the camera's broadband filter (wavelengths of 739 nanometers plus or minus 338 nanometers).

  1. Arctic Sea Ice Maximum 2011

    NASA Video Gallery

    AMSR-E Arctic Sea Ice: September 2010 to March 2011: Scientists tracking the annual maximum extent of Arctic sea ice said that 2011 was among the lowest ice extents measured since satellites began ...

  2. Bacterial Ice Crystal Controlling Proteins

    PubMed Central

    Lorv, Janet S. H.; Rose, David R.; Glick, Bernard R.

    2014-01-01

    Across the world, many ice active bacteria utilize ice crystal controlling proteins for aid in freezing tolerance at subzero temperatures. Ice crystal controlling proteins include both antifreeze and ice nucleation proteins. Antifreeze proteins minimize freezing damage by inhibiting growth of large ice crystals, while ice nucleation proteins induce formation of embryonic ice crystals. Although both protein classes have differing functions, these proteins use the same ice binding mechanisms. Rather than direct binding, it is probable that these protein classes create an ice surface prior to ice crystal surface adsorption. Function is differentiated by molecular size of the protein. This paper reviews the similar and different aspects of bacterial antifreeze and ice nucleation proteins, the role of these proteins in freezing tolerance, prevalence of these proteins in psychrophiles, and current mechanisms of protein-ice interactions. PMID:24579057

  3. [Tail Plane Icing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Aviation Safety Program initiated by NASA in 1997 has put greater emphasis in safety related research activities. Ice-contaminated-tailplane stall (ICTS) has been identified by the NASA Lewis Icing Technology Branch as an important activity for aircraft safety related research. The ICTS phenomenon is characterized as a sudden, often uncontrollable aircraft nose- down pitching moment, which occurs due to increased angle-of-attack of the horizontal tailplane resulting in tailplane stall. Typically, this phenomenon occurs when lowering the flaps during final approach while operating in or recently departing from icing conditions. Ice formation on the tailplane leading edge can reduce tailplane angle-of-attack range and cause flow separation resulting in a significant reduction or complete loss of aircraft pitch control. In 1993, the Federal Aviation Authority (FAA) and NASA embarked upon a four-year research program to address the problem of tailplane stall and to quantify the effect of tailplane ice accretion on aircraft performance and handling characteristics. The goals of this program, which was completed in March 1998, were to collect aerodynamic data for an aircraft tail with and without ice contamination and to develop analytical methods for predicting the effects of tailplane ice contamination. Extensive dry air and icing tunnel tests which resulted in a database of the aerodynamic effects associated with tailplane ice contamination. Although the FAA/NASA tailplane icing program generated some answers regarding ice-contaminated-tailplane stall (ICTS) phenomena, NASA researchers have found many open questions that warrant further investigation into ICTS. In addition, several aircraft manufacturers have expressed interest in a second research program to expand the database to other tail configurations and to develop experimental and computational methodologies for evaluating the ICTS phenomenon. In 1998, the icing branch at NASA Lewis initiated a second

  4. Commercial aviation icing research requirements

    NASA Technical Reports Server (NTRS)

    Koegeboehn, L. P.

    1981-01-01

    A short range and long range icing research program was proposed. A survey was made to various industry and goverment agencies to obtain their views of needs for commercial aviation ice protection. Through these responsed, other additional data, and Douglas Aircraft icing expertise; an assessment of the state-of-the-art of aircraft icing data and ice protection systems was made. The information was then used to formulate the icing research programs.

  5. Academic Airframe Icing Perspective

    NASA Technical Reports Server (NTRS)

    Bragg, Mike; Rothmayer, Alric; Thompson, David

    2009-01-01

    2-D ice accretion and aerodynamics reasonably well understood for engineering applications To significantly improve our current capabilities we need to understand 3-D: a) Important ice accretion physics and modeling not well understood in 3-D; and b) Aerodynamics unsteady and 3-D especially near stall. Larger systems issues important and require multidisciplinary team approach

  6. Making an Ice Core.

    ERIC Educational Resources Information Center

    Kopaska-Merkel, David C.

    1995-01-01

    Explains an activity in which students construct a simulated ice core. Materials required include only a freezer, food coloring, a bottle, and water. This hands-on exercise demonstrates how a glacier is formed, how ice cores are studied, and the nature of precision and accuracy in measurement. Suitable for grades three through eight. (Author/PVD)

  7. Fire beneath the ice

    SciTech Connect

    Monastersky, R.

    1993-02-13

    A volcano discovered six years ago by researchers Blankenship and Bell under Antarctica poses questions about a potential climatic catastrophe. The researchers claim that the volcano is still active, erupting occasionally and growing. A circular depression on the surface of the ice sheet has ice flowing into it and is used to provide a portrait of the heat source. The volcano is on a critical transition zone within West Antarctica with fast flowing ice streams directly downhill. Work by Blankenship shows that a soft layer of water-logged sediments called till provide the lubricating layer on the underside of the ice streams. Volcanos may provide the source of this till. The ice streams buffer the thick interior ice from the ocean and no one know what will happen if the ice streams continue to shorten. These researchers believe their results indicate that the stability of West Antarctica ultimately depends less on the current climate than on the location of heat and sediments under the ice and the legacy of past climatic changes.

  8. Larsen B Ice Shelf

    Atmospheric Science Data Center

    2013-04-16

    ... ice shelf and the rough crevasses of glaciers appear orange. In contrast to the spectral composite, which provides information on ... surfaces appear brighter on their illuminated faces, the orange color in the multi-angle composite suggests a macroscopically rough ice ...

  9. Ice forming experiment

    NASA Technical Reports Server (NTRS)

    Vali, G.

    1982-01-01

    A low gravity experiment to assess the effect of the presence of supercooled cloud droplets on the diffusional growth rate of ice crystals is described. The theoretical work and the feasibility studies are summarized. The nucleation of ice crystals in supercooled clouds is also discussed.

  10. Ice Core Investigations

    ERIC Educational Resources Information Center

    Krim, Jessica; Brody, Michael

    2008-01-01

    What can glaciers tell us about volcanoes and atmospheric conditions? How does this information relate to our understanding of climate change? Ice Core Investigations is an original and innovative activity that explores these types of questions. It brings together popular science issues such as research, climate change, ice core drilling, and air…

  11. Amery Ice Shelf

    Atmospheric Science Data Center

    2013-04-16

    article title:  Amery Ice Shelf's "Loose Tooth" Gets Looser     View Larger Image The Amery Ice Shelf is an important dynamic system responsible for draining about 16% of ... glaciers. Mass loss from the system occurs through basal melting and iceberg calving. These images from the Multi-angle Imaging ...

  12. Rheology of glacier ice.

    PubMed

    Jezek, K C; Alley, R B; Thomas, R H

    1985-03-15

    A new method for calculating the stress field in bounded ice shelves is used to compare strain rate and deviatoric stress on the Ross Ice Shelf, Antarctica. The analysis shows that strain rate (per second) increases as the third power of deviatoric stress (in newtons per square meter), with a constant of proportionality equal to 2.3 x 10(-25). PMID:17793768

  13. Spectroscopic signature for ferroelectric ice

    NASA Astrophysics Data System (ADS)

    Wójcik, Marek J.; Gług, Maciej; Boczar, Marek; Boda, Łukasz

    2014-09-01

    Various forms of ice exist within our galaxy. Particularly intriguing type of ice - ‘ferroelectric ice' was discovered experimentally and is stable in temperatures below 72 K. This form of ice can generate enormous electric fields and can play an important role in planetary formation. In this letter we present Car-Parrinello simulation of infrared spectra of ferroelectric ice and compare them with spectra of hexagonal ice. Librational region of the spectra can be treated as spectroscopic signature of ice XI and can be of help to identify ferroelectric ice in the Universe.

  14. Overview of LIMEX'87 ice observations

    NASA Technical Reports Server (NTRS)

    Carsey, Frank D.; Holt, Benjamin; Argus, Susan A. Digby; Collins, Michael J.; Livingstone, Charles E.

    1989-01-01

    Ice observations, results, and conclusions are summarized for the March 1987 Labrador Ice Margin Experiment (LIMEX'87), an international oceanographic study conducted in the pack ice of the Grand Banks area off the coast of Newfoundland. Included are the ice extent, floe size and thickness, ice kinematics and rheology, ice microwave properties, oceanic properties under the ice, and penetration of swell into the ice.

  15. Quantum theory of rotational isomerism and Hill equation

    SciTech Connect

    Ugulava, A.; Toklikishvili, Z.; Chkhaidze, S.; Abramishvili, R.; Chotorlishvili, L.

    2012-06-15

    The process of rotational isomerism of linear triatomic molecules is described by the potential with two different-depth minima and one barrier between them. The corresponding quantum-mechanical equation is represented in the form that is a special case of the Hill equation. It is shown that the Hill-Schroedinger equation has a Klein's quadratic group symmetry which, in its turn, contains three invariant subgroups. The presence of these subgroups makes it possible to create a picture of energy spectrum which depends on a parameter and has many merging and branch points. The parameter-dependent energy spectrum of the Hill-Schroedinger equation, like Mathieu-characteristics, contains branch points from the left and from the right of the demarcation line. However, compared to the Mathieu-characteristics, in the Hill-Schroedinger equation spectrum the 'right' points are moved away even further for some distance that is the bigger, the bigger is the less deep well. The asymptotic wave functions of the Hill-Schroedinger equation for the energy values near the potential minimum contain two isolated sharp peaks indicating a possibility of the presence of two stable isomers. At high energy values near the potential maximum, the height of two peaks decreases, and between them there appear chaotic oscillations. This form of the wave functions corresponds to the process of isomerization.

  16. Magma hybridisation at Soufriere Hills Volcano, Montserrat

    NASA Astrophysics Data System (ADS)

    Humphreys, Madeleine; Edmonds, Marie; Christopher, Thomas; Hards, Vicky

    2010-05-01

    Arc volcanoes commonly show evidence of mingling between mafic and silicic magma. For example, the Soufrière Hills Volcano, Montserrat typically erupts andesitic magma containing basaltic to basaltic-andesite inclusions. However, the andesite also contains a wide variety of phenocryst textures as well as strongly zoned microlites, suggesting that more intimate physical mixing also occurs. Analysis of minor elements in both phenocrysts and microlites allows the discrimination of different crystal populations, and provides insight into their origins. Microlites of plagioclase and orthopyroxene are chemically distinct from the phenocrysts, being enriched in Fe and Mg, and Al and Ca respectively. However, they are indistinguishable from the compositions of these phases in the mafic inclusions. Microlite compositions also give anomalously high temperatures using standard geothermometry techniques, similar to those of the mafic inclusions. Compositions of clinopyroxene from overgrowth rims on quartz and orthopyroxene and coarse-grained breakdown rims on hornblende, are identical to those from the mafic inclusions, indicating that these rims form during interaction with mafic magma. We infer that the inclusions disaggregated under conditions of high shear stress during ascent in the conduit, transferring mafic material into the andesite groundmass. This implies that the mafic component of the system is greater than previously determined from the volume proportion of mafic enclaves. The presence of mafic-derived microlites in the andesite groundmass also means that care must be taken when using this as a starting material for phase equilibrium experiments. Melt inclusions and matrix glasses in the erupted include an anomalously K2O-rich population which overlaps with residual (high-K2O, high-TiO2) mafic inclusion glass. These glasses represent the effects of physical mixing with mafic magma, both during ascent and by diffusive exchange during the formation of mafic

  17. SMILES ice cloud products

    NASA Astrophysics Data System (ADS)

    MilláN, L.; Read, W.; Kasai, Y.; Lambert, A.; Livesey, N.; Mendrok, J.; Sagawa, H.; Sano, T.; Shiotani, M.; Wu, D. L.

    2013-06-01

    Upper tropospheric water vapor and clouds play an important role in Earth's climate, but knowledge of them, in particular diurnal variation in deep convective clouds, is limited. An essential variable to understand them is cloud ice water content. The Japanese Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) on board the International Space Station (ISS) samples the atmosphere at different local times allowing the study of diurnal variability of atmospheric parameters. We describe a new ice cloud data set consisting of partial Ice Water Path and Ice Water Content. Preliminary comparisons with EOS-MLS, CloudSat-CPR and CALIOP-CALIPSO are presented. Then, the diurnal variation over land and over open ocean for partial ice water path is reported. Over land, a pronounced diurnal variation peaking strongly in the afternoon/early evening was found. Over the open ocean, little temporal dependence was encountered. This data set is publicly available for download in HDF5 format.

  18. Rotating ice blocks

    NASA Astrophysics Data System (ADS)

    Dorbolo, Stephane; Adami, Nicolas; Grasp Team

    2014-11-01

    The motion of ice discs released at the surface of a thermalized bath was investigated. As observed in some rare events in the Nature, the discs start spinning spontaneously. The motor of this motion is the cooling of the water close to the ice disc. As the density of water is maximum at 4°C, a downwards flow is generated from the surface of the ice block to the bottom. This flow generates the rotation of the disc. The speed of rotation depends on the mass of the ice disc and on the temperature of the bath. A model has been constructed to study the influence of the temperature of the bath. Finally, ice discs were put on a metallic plate. Again, a spontaneous rotation was observed. FNRS is thanked for financial support.

  19. Polarimetric road ice detection

    NASA Astrophysics Data System (ADS)

    Drummond, Krista

    This thesis investigated the science behind polarimetric road ice detection systems. Laboratory Mueller matrix measurements of a simulated road under differing surface conditions were collected searching for a discriminatory polarization property. These Mueller matrices were decomposed into depolarization, diattenuation, and retardance. Individual sample surface polarization properties were then calculated from these three unique matrices and compared. Specular and off-specular reflection responses of each sample were collected. Four polarization properties stood out for having high separation between dry and iced measurements: Depolarization Index, Linear Diattenuation, Linear Polarizance, and Linear Retardance. Through our investigation polarimetric ice detection is possible. Continued research of the polarization properties of road ice can result in the development of a road ice detection system. Proposed deployment methods of such a system have been outlined following the analysis of the data collected in this experiment.

  20. Coating Reduces Ice Adhesion

    NASA Technical Reports Server (NTRS)

    Smith, Trent; Prince, Michael; DwWeese, Charles; Curtis, Leslie

    2008-01-01

    The Shuttle Ice Liberation Coating (SILC) has been developed to reduce the adhesion of ice to surfaces on the space shuttle. SILC, when coated on a surface (foam, metal, epoxy primer, polymer surfaces), will reduce the adhesion of ice by as much as 90 percent as compared to the corresponding uncoated surface. This innovation is a durable coating that can withstand several cycles of ice growth and removal without loss of anti-adhesion properties. SILC is made of a binder composed of varying weight percents of siloxane(s), ethyl alcohol, ethyl sulfate, isopropyl alcohol, and of fine-particle polytetrafluoroethylene (PTFE). The combination of these components produces a coating with significantly improved weathering characteristics over the siloxane system alone. In some cases, the coating will delay ice formation and can reduce the amount of ice formed. SILC is not an ice prevention coating, but the very high water contact angle (greater than 140 ) causes water to readily run off the surface. This coating was designed for use at temperatures near -170 F (-112 C). Ice adhesion tests performed at temperatures from -170 to 20 F (-112 to -7 C) show that SILC is a very effective ice release coating. SILC can be left as applied (opaque) or buffed off until the surface appears clear. Energy dispersive spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS) data show that the coating is still present after buffing to transparency. This means SILC can be used to prevent ice adhesion even when coating windows or other objects, or items that require transmission of optical light. Car windshields are kept cleaner and SILC effectively mitigates rain and snow under driving conditions.

  1. Tensile properties of impact ices

    NASA Technical Reports Server (NTRS)

    Chu, M. L.; Scavuzzo, R. J.; Kellackey, C. J.

    1992-01-01

    A special test apparatus was developed to measure the tensile strength of impact ices perpendicular to the direction of growth. The apparatus consists of a split tube carefully machined to minimize the effect of the joint on impact ice strength. The tube is supported in the wind tunnel by two carefully aligned bearings. During accretion the tube is turned slowly in the icing cloud to form a uniform coating of ice on the split tube specimen. The two halves of the split tube are secured firmly by a longitudinal bolt to prevent relative motion between the two halves during ice accretion and handling. Tensile test strength results for a variety of icing conditions were obtained. Both glaze and rime ice conditions were investigated. In general, the tensile strength of impact ice was significantly less than refrigerator ice. Based on the limited data taken, the median strength of rime ice was less than glaze ice. However, the mean values were similar.

  2. Getting closer to Congress: A scientist's arrival on Capitol Hill

    NASA Astrophysics Data System (ADS)

    Davis, Jana L. D.

    Where is this “hill,” and how do I get there? During my first month here in Washington, D.C., as I was rushing down First Street on my way from the House of Representatives to the Senate (I wasn't really in a hurry but I was practicing for what others promised lies ahead), someone stopped me to ask for directions to “the Hill.” Just two weeks prior, I had been in the same boat, having never worked in the policy world and having spent many years in California where topography is defined a little differently. By this time, however, I knew the answer. To the woman seeking topography I proudly glanced down at my one-day-old Senate staff badge and said, “You're here, ma'am. You're on the Hill.”

  3. Ionospheric plasma temperatures during 1976-2001 over Millstone Hill

    NASA Astrophysics Data System (ADS)

    Zhang, Shun-Rong; Holt, John M.

    Incoherent scatter measurements have been made since the 1960s over Millstone Hill. Zenith antenna data since 1976 and steerable antenna data since 1980 are now available through the WWW-based Madrigal database system. By analyzing this large volume of data in a systematic way, this paper provides an updated climatology of the ionospheric temperature over Millstone Hill, including diurnal variations, solar activity dependences, and the electron density Ne and electron temperature Te relationship. The daytime Te in the F2-layer is found to increase with the increasing solar activity in summer, and to decrease in winter. The inverse correlation between Ne and Te prevails in winter and equinox but is much less pronounced or even disappears in summer. Based on the database, Millstone Hill incoherent scatter radar models are established, and compared with the latest International Reference Model.

  4. The relation between Hill's equation and individual muscle properties.

    PubMed

    Thaller, S; Wagner, H

    2004-12-01

    In this paper we deal with movement-independent individual muscle properties derived from Hill's equation. Relations between these properties are found by theoretical considerations. We define a dimensionless quantity that turns out to play a major role in characterizing individual muscle properties, and we analyse normalization and symmetry behaviour of the parameters in Hill's equation. This leads to a systematic, transparent, and useful overview of mathematical relations involving muscle parameters. We examine the experimentally determined parameters of 62 subjects to find additional empirical relations between the muscle properties described by the parameters of Hill's equation. In the light of the theoretical end empirical results we investigate the connections between maximum efficiency, endurance, and fibre composition. PMID:15501465

  5. The relationship between ice velocity and bed topography on Byrd Glacier, Antarctica

    NASA Astrophysics Data System (ADS)

    Child, S.; Stearns, L. A.; Purdon, K.; Li, J.; Rodriguez-Morales, F.; Crowe, R.; Gomez-Garcia, D.

    2012-12-01

    Bed topography controls the pattern and magnitude of ice velocity, far into the catchment basin of many Antarctic outlet glaciers. Predictive models of glacier dynamics and ice sheet mass balance rely on well-prescribed bed topography, but in many regions bed topography is largely unknown. This particular study investigates the relationship between bed and surface topography and ice velocity in the catchment basin and trunk of Byrd Glacier. Byrd Glacier drains ~19 % of the area of the East Antarctic Ice Sheet (1,070,400 km2), and has the potential to play a significant role in the ice sheet's total mass balance. In 2011/2012, the Center for Remote Sensing of Ice Sheets (CReSIS) collected airborne radar data over Byrd Glacier. These new measurements of bed topography, along with updated surface digital elevation models (DEMs) and basin-wide ice velocity maps, are used to investigate the flow dynamics of Byrd Glacier with improved accuracy. Surface DEMs are derived from new high-resolution WorldView imagery; ice velocity is derived from repeat visible imagery, coupled with InSAR results (Rignot et al., 2011). Results exhibit relatively smooth depressions surrounding the inferred subglacial lakes, ~200 km upflow of the grounding line on Byrd Glacier (Stearns et al., 2008). Downflow of the subglacial lakes is a complex pattern of hills and valleys as ice enters the glacier trunk. At the mouth of the trunk is a large overdeepening (~2500 m) that coincides with faster ice flow. We use along- and across-flow radar profiles to perform detailed comparisons of ice velocity, bed topography and surface topography throughout the Byrd Glacier region. Gridded products are used to complete an updated force balance assessment. These results provide us with a better understanding of Byrd Glacier's flow dynamics and sensitivity to external perturbations.

  6. Climate science: Ice streams waned as ice sheets shrank

    NASA Astrophysics Data System (ADS)

    Briner, Jason P.

    2016-02-01

    It emerges that ice discharge from a major ice sheet did not increase rapidly at the end of the most recent ice age. The finding points to steady, not catastrophic, ice-sheet loss and sea-level rise on millennial timescales. See Letter p.322

  7. Mars Exploration Rover APXS Results from Matijevic Hill

    NASA Technical Reports Server (NTRS)

    Cohen, B. A.; Clark, B. C.; Gellert, R.; Klingelhoefer, G.; Ming, D. W.; Mittlefehldt, D. W.; Morris, R. V.; Schrader, C. M.; Schroeder, C.; Yen, A. S.; Economou, T.; deSouza, P.; Jolliff, B. L.; Arvidson, R. A.; Squyres, S. W.

    2013-01-01

    Correlation analysis of APXS results on the eastern slope rocks indicate that the Matijevic Hill rocks are overall compositionally distinct from the Shoemaker Formation rocks [6]. Compared to the Shoemaker impactites, Matijevic Hill rocks are higher in Al, Si, and Ni, and lower in Ti, Fe, and Zn. No significant variation is evident in the APXS analyses that indicate the presence of a smectite or other phyllosilicate, as opposed to basaltic rocks. However, APXS data cannot in themselves rule out phyllosilicates. If indeed this material contains smectite, as seen from orbit, it implies that the rock has been isochemically altered to create the phyllosilicate content. The Cl content of the Cape York rocks is relatively high, and whereas the S/Cl ratio in the Burns Formation is 4x higher than in soil, in the Cape York rocks it is lower than in soil. These trends indicate that the alteration processes and types of aqueous salt loads were different between Cape York and Meridiani. In addition, significant deviations from the Martian Mn/Fe ratio are observed in Whitewater Lake coatings and the altered Grasford/Deadwood rocks (Fig. 3). These variations indicate that the redox/pH conditions during alteration of the Shoemaker Formation rocks and the Matijevic Hill rocks were similar, but that the Deadwood/Grasberg unit may have undergone alteration under different conditions, possibly at a later time. The Matijevic Hill outcrops appear to share a common genetic origin. It is not yet clear whether both the Shoemaker impactites and Matijevic Hill rocks are related to the formation of Endeavour Crater, or whether the Matijevic Hill suite represents a prior episode of Martian impact or volcanism. Opportunity continues to investigate both hypotheses.

  8. Icing Cloud Calibration of the NASA Glenn Icing Research Tunnel

    NASA Technical Reports Server (NTRS)

    Ide, Robert F.; Oldenburg, John R.

    2001-01-01

    The icing research tunnel at the NASA Glenn Research Center underwent a major rehabilitation in 1999, necessitating recalibration of the icing clouds. This report describes the methods used in the recalibration, including the procedure used to establish a uniform icing cloud and the use of a standard icing blade technique for measurement of liquid water content. The instruments and methods used to perform the droplet size calibration are also described. The liquid water content/droplet size operating envelopes of the icing tunnel are shown for a range of airspeeds and compared to the FAA icing certification criteria. The capabilities of the IRT to produce large droplet icing clouds is also detailed.

  9. Analysis of iced wings

    NASA Technical Reports Server (NTRS)

    Cebeci, T.; Chen, H. H.; Kaups, K.; Schimke, S.; Shin, J.

    1992-01-01

    A method for computing ice shapes along the leading edge of a wing and a method for predicting its aerodynamic performance degradation due to icing is described. Ice shapes are computed using an extension of the LEWICE code which was developed for airfoils. The aerodynamic properties of the iced wing are determined with an interactive scheme in which the solutions of the inviscid flow equations are obtained from a panel method and the solutions of the viscous flow equations are obtained from an inverse three-dimensional finite-difference boundary-layer method. A new interaction law is used to couple the inviscid and viscous flow solutions. The application of the LEWICE wing code to the calculation of ice shapes on a MS-317 swept wing shows good agreement with measurements. The interactive boundary-layer method is applied to a tapered ice wing in order to study the effect of icing on the aerodynamic properties of the wing at several angles of attack.

  10. Skylab floating ice experiment

    NASA Technical Reports Server (NTRS)

    Campbell, W. J. (Principal Investigator); Ramseier, R. O.; Weaver, R. J.; Weeks, W. F.

    1975-01-01

    The author has identified the following significant results. Coupling of the aircraft data with the ground truth observations proved to be highly successful with interesting results being obtained with IR and SLAR passive microwave techniques, and standard photography. Of particular interest were the results of the PMIS system which operated at 10.69 GHz with both vertical and horizontal polarizations. This was the first time that dual polarized images were obtained from floating ice. In both sea and lake ice, it was possible to distinguish a wide variety of thin ice types because of their large differences in brightness temperatures. It was found that the higher brightness temperature was invariably obtained in the vertically polarized mode, and as the age of the ice increases the brightness temperature increases in both polarizations. Associated with this change in age, the difference in temperature was observed as the different polarizations decreased. It appears that the horizontally polarized data is the most sensitive to variations in ice type for both fresh water and sea ice. The study also showed the great amount of information on ice surface roughness and deformation patterns that can be obtained from X-band SLAR observations.

  11. Ice sheets and nitrogen

    PubMed Central

    Wolff, Eric W.

    2013-01-01

    Snow and ice play their most important role in the nitrogen cycle as a barrier to land–atmosphere and ocean–atmosphere exchanges that would otherwise occur. The inventory of nitrogen compounds in the polar ice sheets is approximately 260 Tg N, dominated by nitrate in the much larger Antarctic ice sheet. Ice cores help to inform us about the natural variability of the nitrogen cycle at global and regional scale, and about the extent of disturbance in recent decades. Nitrous oxide concentrations have risen about 20 per cent in the last 200 years and are now almost certainly higher than at any time in the last 800 000 years. Nitrate concentrations recorded in Greenland ice rose by a factor of 2–3, particularly between the 1950s and 1980s, reflecting a major change in NOx emissions reaching the background atmosphere. Increases in ice cores drilled at lower latitudes can be used to validate or constrain regional emission inventories. Background ammonium concentrations in Greenland ice show no significant recent trend, although the record is very noisy, being dominated by spikes of input from biomass burning events. Neither nitrate nor ammonium shows significant recent trends in Antarctica, although their natural variations are of biogeochemical and atmospheric chemical interest. Finally, it has been found that photolysis of nitrate in the snowpack leads to significant re-emissions of NOx that can strongly impact the regional atmosphere in snow-covered areas. PMID:23713125

  12. NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT ...

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

    NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT EDGE IS THE SINGLE CYLINDER “HOT SHOT” ENGINE THAT PROVIDED POWER FOR THE MILL. JUST IN FRONT OF IT IS AN ARRASTRA. AT CENTER IS THE BALL MILL AND SECONDARY ORE BIN. JUST TO THE RIGHT OF THE BALL MILL IS A RAKE CLASSIFIER, AND TO THE RIGHT ARE THE CONCENTRATION TABLES. WARM SPRINGS CAMP IS IN THE DISTANCE. SEE CA-292-4 FOR IDENTICAL B&W NEGATIVE. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  13. NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT ...

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

    NORTH ELEVATION OF GOLD HILL MILL, LOOKING SOUTH. AT LEFT EDGE IS THE SINGLE CYLINDER “HOT SHOT” ENGINE THAT PROVIDED POWER FOR THE MILL. JUST IN FRONT OF IT IS AN ARRASTRA. AT CENTER IS THE BALL MILL AND SECONDARY ORE BIN. JUST TO THE RIGHT OF THE BALL MILL IS A RAKE CLASSIFIER, AND TO THE RIGHT ARE THE CONCENTRATION TABLES. WARM SPRINGS CAMP IS IN THE DISTANCE. SEE CA-292-17 (CT) FOR IDENTICAL COLOR TRANSPARENCY. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

  14. 2013 strategic petroleum reserve big hill well integrity grading report.

    SciTech Connect

    Lord, David L.; Roberts, Barry L.; Lord, Anna C. Snider; Bettin, Giorgia; Sobolik, Steven Ronald; Park, Byoung Yoon; Rudeen, David Keith; Eldredge, Lisa; Wynn, Karen; Checkai, Dean; Perry, James Thomas

    2014-02-01

    This report summarizes the work performed in developing a framework for the prioritization of cavern access wells for remediation and monitoring at the Big Hill Strategic Petroleum Reserve site. This framework was then applied to all 28 wells at the Big Hill site with each well receiving a grade for remediation and monitoring. Numerous factors affecting well integrity were incorporated into the grading framework including casing survey results, cavern pressure history, results from geomechanical simulations, and site geologic factors. The framework was developed in a way as to be applicable to all four of the Strategic Petroleum Reserve sites.

  15. A priori estimates for the Hill and Dirac operators

    NASA Astrophysics Data System (ADS)

    Korotyaev, E.

    2008-09-01

    The Hill operator Ty = -y″ + q'( t) y is considered in L 2(ℝ), where q ∈ L 2(0, 1) is a periodic real potential. The spectrum of T is absolutely continuous and consists of bands separated by gaps. We obtain a priori estimates of gap lengths, effective masses, and action variables for the KDV equation. In the proof of these results, the analysis of a conformal mapping corresponding to quasimomentum of the Hill operator is used. Similar estimates for the Dirac operator are obtained.

  16. Analysis of Subsidence Data for the Big Hill Site, Texas

    SciTech Connect

    Bauer, Stephen J.

    1999-06-01

    The elevation change data measured at the Big Hill SPR site over the last 10 years has been studied and a model utilized to project elevation changes into the future. The subsidence rate at Big Hill is low in comparison with other Strategic Petroleum Reserve sites and has decreased with time due to the maintenance of higher operating pressures and the normal decrease in creep closure rate of caverns with time. However, the subsidence at the site is projected to continue. A model was developed to project subsidence values 20 years into the future; no subsidence related issues are apparent from these projections.

  17. Scientific progress on the Fenton Hill HDR project since 1983

    SciTech Connect

    Brown, D.W.; Duchane, D.V.

    1998-02-01

    The modern HDR concept originated at the Los Alamos National Laboratory and was first demonstrated at Fenton Hill, NM. Experience gained during the development of the deeper HDR reservoir at Fenton Hill clearly showed that HDR reservoirs are formed by opening pre-existing, but sealed, multiply connected joint sets. Subsequent flow testing indicated that sustained operation of HDR systems under steady state conditions is feasible. The most significant remaining HDR issues are related to economics and locational flexibility. Additional field test sites are needed to advance the understanding of HDR technology so that the vast potential of this resource can be economically realized around the world.

  18. Penzias, Arno Allan (1933-)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Radioscientist, born in Munich in Germany, Nobel prizewinner (1978) `for the discovery of cosmic microwave background radiation', a refugee from Germany at the age of 6, found his way to America and experience in microwave physics. Joined Bell Laboratories, Holmdel, New Jersey, searched for and investigated line emission from the interstellar OH molecule. Was able to gain the use of a large radio...

  19. Cyclic steps on ice

    NASA Astrophysics Data System (ADS)

    Yokokawa, M.; Izumi, N.; Naito, K.; Parker, G.; Yamada, T.; Greve, R.

    2016-05-01

    Boundary waves often form at the interface between ice and fluid flowing adjacent to it, such as ripples under river ice covers, and steps on the bed of supraglacial meltwater channels. They may also be formed by wind, such as the megadunes on the Antarctic ice sheet. Spiral troughs on the polar ice caps of Mars have been interpreted to be cyclic steps formed by katabatic wind blowing over ice. Cyclic steps are relatives of upstream-migrating antidunes. Cyclic step formation on ice is not only a mechanical but also a thermodynamic process. There have been very few studies on the formation of either cyclic steps or upstream-migrating antidunes on ice. In this study, we performed flume experiments to reproduce cyclic steps on ice by flowing water, and found that trains of steps form when the Froude number is larger than unity. The features of those steps allow them to be identified as ice-bed analogs of cyclic steps in alluvial and bedrock rivers. We performed a linear stability analysis and obtained a physical explanation of the formation of upstream-migrating antidunes, i.e., precursors of cyclic steps. We compared the results of experiments with the predictions of the analysis and found the observed steps fall in the range where the analysis predicts interfacial instability. We also found that short antidune-like undulations formed as a precursor to the appearance of well-defined steps. This fact suggests that such antidune-like undulations correspond to the instability predicted by the analysis and are precursors of cyclic steps.

  20. Strength of ice

    SciTech Connect

    Not Available

    1984-04-01

    In order to model the evolution and current state of Callisto and Ganymede (Jupiter's two largest moons), which are similar in mass, density, temperature, and apparent composition (about 75% ice by volume) but different in appearance, we are studying the flow properties of ice under extreme conditions. With our new testing apparatus, we have determined that ice is very much weaker at low temperatures (below 160 K) than had been believed. This finding partially explains some of the unusual features found on these Jovian moons, although many questions are still being investigated.

  1. An ice shelf breakup

    SciTech Connect

    Fahnestock, M.

    1996-02-09

    Glaciers and ice sheets are controlled by the climate and must change if the conditions that led to their current configurations are changing. These ice masses exist at the interface between the atmosphere, which provides sustaining snowfall and thermal regulation, and the land, which provides a stable base and in many cases the elevation required to reach suitably cold conditions. Ice sheets and glaciers are distributed around the globe and can serve as potential indicators of past climate variability and current climatic trends. 9 refs.

  2. Ice nucleation terminology

    NASA Astrophysics Data System (ADS)

    Vali, G.; DeMott, P.; Möhler, O.; Whale, T. F.

    2014-08-01

    Progress in the understanding of ice nucleation is being hampered by the lack of uniformity in how some terms are used in the literature. This even extends to some ambiguity of meanings attached to some terms. Suggestions are put forward here for common use of terms. Some are already well established and clear of ambiguities. Others are less engrained and will need a conscious effort in adoption. Evolution in the range of systems where ice nucleation is being studied enhances the need for a clear nomenclature. The ultimate limit in the clarity of definitions is, of course, the limited degree to which ice nucleation processes are understood.

  3. Ice Stream Dynamics during Deglaciation of the Laurentide Ice Sheet

    NASA Astrophysics Data System (ADS)

    Stokes, C.; Margold, M.; Clark, C.

    2014-12-01

    Ice streams can rapidly drain large sectors of ice sheet interiors. At present, they account for approximately 50% and 90% of the mass loss from Greenland and Antarctica, respectively, but there are concerns over recent increases in ice discharge. This has been linked to atmospheric and oceanic warming, but the longer-term implications for ice sheet deglaciation are less clear. A key question is whether the activity of ice streams is predictably linked to climate-driven ice sheet mass balance, or whether their activity might accelerate deglaciation. To explore this, we analyse ice streaming during deglaciation of the Laurentide Ice Sheet (LIS) from ~18 to ~7 ka. Following a recent mapping inventory, we bracket the timing of >100 ice streams using published ice margin chronologies. At the Last Glacial Maximum (LGM), ice streams formed a drainage network similar to modern ice sheets. Numerous ice streams were located in topographic troughs and likely operated for thousands of years from the LGM. These drained the marine-based sectors of the northern and eastern margins of the ice sheet until ~11 ka and show a degree of spatial self-organisation. Other ice streams operated on much shorter time-scales and turned on and off, perhaps in as little as a few hundred years. These include large ice streams that switched positions over sedimentary bedrock at the western and southern terrestrial margins until ~13 ka. As the LIS retreated onto its low-relief and predominantly crystalline bedrock interior (after ~11 ka), a smaller number of large ice streams operated that were very wide (50-100 km), and have no modern analogue. Overall, the number of ice streams decreased during deglaciation and they drained a smaller proportion of the ice sheet margin: 30% at the LGM (similar to present-day Antarctica), 15% at 12 ka, and 12% at 10 ka. We use simple scaling relationships to estimate the mass loss delivered by ice streams and examine their role during deglaciation.

  4. Climate Data Records (CDRs) for Ice Motion and Ice Age

    NASA Astrophysics Data System (ADS)

    Tschudi, M. A.; Fowler, C.; Maslanik, J. A.; Stroeve, J. C.

    2011-12-01

    Climate Data Records (CDRs) for remotely-sensed Arctic sea ice motion and sea ice age are under development by our group at the University of Colorado, Boulder. The ice motion product, archived at NSIDC, has a considerable history of use, while sea ice age is a relatively new product. Our technique to estimate sea ice motion utilizes images from SSM/I, as well as SMMR and the series of AVHRR sensors to estimate the daily motion of ice parcels. This method is augmented by incorporating ice motion observations from the network of drifting buoys deployed as part of the International Arctic Buoy Program. Our technique to calculate ice age relies on following the actual age of the ice for each ice parcel, categorizing the parcel as first-year ice, second-year, ice, etc. based on how many summer melt seasons the ice parcel survives. Both of these research-grade products have been interpolated onto 25x25 km grid points spanning the entire Arctic Ocean using the Equal-Area Scalable Earth (EASE) grid. Datasets generated from this program have shown that the Arctic ice cover has experienced a significant (> 70%) decline in multiyear ice over the last 20 years, leaving a younger ice cover in 2011. By comparing ice age derived by the Lagrangian tracking method to ice thickness estimated by Ice, Cloud and land Elevation Satellite (ICESat) Geoscience Laser Altimeter System (GLAS) data, it is observed that ice age is linearly related to ice thickness, up to an age of 10 years. Therefore, the shift in dominance of multiyear ice to first-year ice relates to a significant thinning of the ice. This thinning is estimated to correspond to a 40% reduction in ice volume in the last 20 years. An ancillary dataset (APP-X) produced by the University of Wisconsin, Madison has been combined with the ice motion product to monitor the properties of the sea ice parcels tracked by the ice motion product. This dataset includes ice surface and 2-meter air temperature, albedo, downwelling shortwave

  5. Arctic Sea ice model sensitivities.

    SciTech Connect

    Peterson, Kara J.; Bochev, Pavel Blagoveston; Paskaleva, Biliana Stefanova

    2010-12-01

    Arctic sea ice is an important component of the global climate system and, due to feedback effects, the Arctic ice cover is changing rapidly. Predictive mathematical models are of paramount importance for accurate estimates of the future ice trajectory. However, the sea ice components of Global Climate Models (GCMs) vary significantly in their prediction of the future state of Arctic sea ice and have generally underestimated the rate of decline in minimum sea ice extent seen over the past thirty years. One of the contributing factors to this variability is the sensitivity of the sea ice state to internal model parameters. A new sea ice model that holds some promise for improving sea ice predictions incorporates an anisotropic elastic-decohesive rheology and dynamics solved using the material-point method (MPM), which combines Lagrangian particles for advection with a background grid for gradient computations. We evaluate the variability of this MPM sea ice code and compare it with the Los Alamos National Laboratory CICE code for a single year simulation of the Arctic basin using consistent ocean and atmospheric forcing. Sensitivities of ice volume, ice area, ice extent, root mean square (RMS) ice speed, central Arctic ice thickness,and central Arctic ice speed with respect to ten different dynamic and thermodynamic parameters are evaluated both individually and in combination using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA). We find similar responses for the two codes and some interesting seasonal variability in the strength of the parameters on the solution.

  6. Advances in ice mechanics - 1987

    SciTech Connect

    Chung, J.S.; Hallam, S.D.; Maatanen, M.; Sinha, N.K.; Sodhi, D.S.

    1987-01-01

    This book presents the papers given at a symposium on the interaction of icebergs with offshore platforms. Topics considered at the symposium included advances in ice mechanics in the United Kingdom, ice mechanics in Finland, recent advances in ice mechanics in Canada, advances in sea ice mechanics in the USA, foundations, monitoring, hazards, risk assessment, and deformation.

  7. Vortex ice in nanostructured superconductors

    SciTech Connect

    Reichhardt, Charles; Reichhardt, Cynthia J; Libal, Andras J

    2008-01-01

    We demonstrate using numerical simulations of nanostructured superconductors that it is possible to realize vortex ice states that are analogous to square and kagome ice. The system can be brought into a state that obeys either global or local ice rules by applying an external current according to an annealing protocol. We explore the breakdown of the ice rules due to disorder in the nanostructure array and show that in square ice, topological defects appear along grain boundaries, while in kagome ice, individual defects appear. We argue that the vortex system offers significant advantages over other artificial ice systems.

  8. Ice interaction with offshore structures

    SciTech Connect

    Cammaert, A.B.; Muggeridge, D.B.

    1988-01-01

    Oil platforms and other offshore structures being built in the arctic regions must be able to withstand icebergs, ice islands, and pack ice. This reference explain the effect ice has on offshore structures and demonstrates design and construction methods that allow such structures to survive in harsh, ice-ridden environments. It analyzes the characteristics of sea ice as well as dynamic ice forces on structures. Techniques for ice modeling and field testing facilitate the design and construction of sturdy, offshore constructions. Computer programs included.

  9. 1. Historic American Buildings Survey Joseph Hill, Photographer August 10th, ...

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

    1. Historic American Buildings Survey Joseph Hill, Photographer August 10th, 1936 (Copied from small photo taken by survey members) OLD APARTMENT HOUSE - Jansonist Colony, Old Apartment House, Main Street, Bishop Hill, Henry County, IL

  10. Evidence for a substantial West Antarctic ice sheet contribution to meltwater pulses and abrupt global sea level rise

    NASA Astrophysics Data System (ADS)

    Fogwill, C. J.; Turney, C. S.; Golledge, N. R.; Etheridge, D. M.; Rubino, M.; Thornton, D.; Woodward, J.; Winter, K.; van Ommen, T. D.; Moy, A. D.; Curran, M. A.; Rootes, C.; Rivera, A.; Millman, H.

    2015-12-01

    During the last deglaciation (21,000 to 7,000years ago) global sea level rise was punctuated by several abrupt meltwater spikes triggered by the retreat of ice sheets and glaciers world-wide. However, the debate regarding the relative timing, geographical source and the physical mechanisms driving these rapid increases in sea level has catalyzed debate critical to predicting future sea level rise and climate. Here we present a unique record of West Antarctic Ice Sheet elevation change derived from the Patriot Hills blue ice area, located close to the modern day grounding line of the Institute Ice Stream in the Weddell Sea Embayment. Combined isotopic signatures and gas volume analysis from the ice allows us to develop a record of local ice sheet palaeo-altitude that is assessed against independent regional high-resolution ice sheet modeling studies, allowing us to demonstrate that past ice sheet elevations across this sector of the WSE were considerably higher than those suggested by current terrestrial reconstructions. We argue that ice in the WSE had a significant influence on both pre and post LGM sea level rise including MWP-1A (~14.6 ka) and during MWP-1B (11.7-11.6 ka), reconciling past sea level rise and demonstrating for the first time that this sector of the WAIS made a significant and direct contribution to post LGM sea level rise.

  11. Palaeo-ice stream pathways in the easternmost Amundsen Sea Embayment, West Antarctica

    NASA Astrophysics Data System (ADS)

    Klages, Johann P.; Kuhn, Gerhard; Graham, Alastair G. C.; Smith, James A.; Hillenbrand, Claus-Dieter; Nitsche, Frank O.; Larter, Rob D.; Gohl, Karsten

    2015-04-01

    Multibeam swath bathymetry datasets collected over the past two decades have been compiled to identify palaeo-ice stream pathways in the easternmost Amundsen Sea Embayment. We mapped 3010 glacial landforms to reconstruct palaeo-ice flow in the ~250 km-long Abbot Glacial Trough that was occupied by a large palaeo-ice stream, fed by two tributaries (Cosgrove and Abbot) that reached the continental shelf edge during the last maximum ice-sheet advance. The mapping has enabled a clear differentiation between glacial landforms interpreted as indicative of wet- (e.g. mega-scale glacial lineations) and cold-based ice (e.g. hill-hole pairs) during the last glaciation of the continental shelf. Both the regions of fast palaeo-ice flow within the palaeo-ice stream troughs, and the regions of slow palaeo-ice flow on adjacent seafloor highs (referred to as inter-ice stream ridges) additionally record glacial landforms such as grounding-zone wedges and recessional moraines that indicate grounding line stillstands of the ice sheet during the last deglaciation from the shelf. As the palaeo-ice stream flowed along a trough with variable geometry and variable subglacial substrate, it appears that trough sections characterized by constrictions and outcropping hard substrate that changes the bed gradient, led the pace of grounding-line retreat to slow and subsequently pause, resulting in the deposition of grounding-zone wedges. The stepped retreat recorded within the Abbot Glacial Trough corresponds well to post-glacial stepped retreat interpreted for the neighbouring Pine Island-Thwaites Palaeo-Ice Stream trough, thus suggesting a uniform pattern of episodic retreat across the eastern Amundsen Sea Embayment. The correlation of episodic retreat features with geological boundaries further emphasises the significance of subglacial geology in steering ice stream flow. Our new geomorphological map of the easternmost Amundsen Sea Embayment resolves the pathways of palaeo-ice streams that

  12. 2011 Sea Ice Minimum

    NASA Video Gallery

    This video shows Arctic sea ice from March 7, 2011, to Sept. 9, 2011, ending with a comparison of the 30-year average minimum extent, shown in yellow, and the Northwest Passage, in red. (no audio) ...

  13. Ross Ice Shelf

    Atmospheric Science Data Center

    2013-04-16

    ... funded by the National Science Foundation, several penguin colonies near the Ross Ice Shelf, Antarctica have not been able to ... affected include one of Antarctica's most populous Adelie penguin colonies, as well as a small colony of Emperor penguins. These ...

  14. Ice age terminations.

    PubMed

    Cheng, Hai; Edwards, R Lawrence; Broecker, Wallace S; Denton, George H; Kong, Xinggong; Wang, Yongjin; Zhang, Rong; Wang, Xianfeng

    2009-10-01

    230Th-dated oxygen isotope records of stalagmites from Sanbao Cave, China, characterize Asian Monsoon (AM) precipitation through the ends of the third- and fourthmost recent ice ages. As a result, AM records for the past four glacial terminations can now be precisely correlated with those from ice cores and marine sediments, establishing the timing and sequence of major events. In all four cases, observations are consistent with a classic Northern Hemisphere summer insolation intensity trigger for an initial retreat of northern ice sheets. Meltwater and icebergs entering the North Atlantic alter oceanic and atmospheric circulation and associated fluxes of heat and carbon, causing increases in atmospheric CO2 and Antarctic temperatures that drive the termination in the Southern Hemisphere. Increasing CO2 and summer insolation drive recession of northern ice sheets, with probable positive feedbacks between sea level and CO2. PMID:19815769

  15. Ice Age Terminations

    NASA Astrophysics Data System (ADS)

    Cheng, Hai; Edwards, R. Lawrence; Broecker, Wallace S.; Denton, George H.; Kong, Xinggong; Wang, Yongjin; Zhang, Rong; Wang, Xianfeng

    2009-10-01

    230Th-dated oxygen isotope records of stalagmites from Sanbao Cave, China, characterize Asian Monsoon (AM) precipitation through the ends of the third- and fourthmost recent ice ages. As a result, AM records for the past four glacial terminations can now be precisely correlated with those from ice cores and marine sediments, establishing the timing and sequence of major events. In all four cases, observations are consistent with a classic Northern Hemisphere summer insolation intensity trigger for an initial retreat of northern ice sheets. Meltwater and icebergs entering the North Atlantic alter oceanic and atmospheric circulation and associated fluxes of heat and carbon, causing increases in atmospheric CO2 and Antarctic temperatures that drive the termination in the Southern Hemisphere. Increasing CO2 and summer insolation drive recession of northern ice sheets, with probable positive feedbacks between sea level and CO2.

  16. Molecules on ice

    SciTech Connect

    Clary, D.C.

    1996-03-15

    The ozone hole that forms in the spring months over the Antarctic is thought to be produced through a network of chemical reactions catalyzed by the surfaces of ice crystals in polar stratospheric clouds (PSCs). A reaction between chlorine reservoir molecules, such as HCl + ClONO{sub 2} > HNO{sub 3} + Cl{sub 2}, is kinetically forbidden in the gas phase but proceeds quickly on the surface of ice and produces Cl{sub 2} molecules that are photodissociated by sunlight to yield the Cl atoms that destroy ozone. This destructive chain of events begins when HCl molecules stick to the ice crystals, and the mechanism for this crucial sticking process has been the subject of much debate. Recent work describes a mechanism that explains how HCl sticks to ice. This article goes on to detail research focusing surface reactions in stratospheric chemistry. 9 refs., 1 fig.

  17. Ice Cream Stick Math.

    ERIC Educational Resources Information Center

    Paddock, Cynthia

    1992-01-01

    Described is a teaching technique which uses the collection of ice cream sticks as a means of increasing awareness of quantity in a self-contained elementary special class for students with learning disabilities and mild mental retardation. (DB)

  18. Ice reconnaissance by satellite

    NASA Technical Reports Server (NTRS)

    Gloersen, P.; Strome, W. M.

    1976-01-01

    The paper describes the significant milestones in the use of satellites for snow and ice monitoring. The feasibility of such monitoring was demonstrated by the Tiros 2 satellite in 1961. Nimbus 1 showed that breaks in the sea ice can be easily monitored during continuous nighttime conditions; Nimbus 3 showed the practicality of delineating regions of active melting of ice and snow in temperate areas. Landsat data have been found to be particularly useful for monitoring and studying glaciers and their attendant surface features. Ice concentration can be determined with reasonable accuracy from a sequence of electronically scanned microwave radiomenter images made aboard Nimbus 5. In the future we can expect improved sensors and spacecraft systems with longer operating lives.

  19. Record Sea Ice Minimum

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Arctic sea ice reached a record low in September 2007, below the previous record set in 2005 and substantially below the long-term average. This image shows the Arctic as observed by the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) aboard NASA's Aqua satellite on September 16, 2007. In this image, blue indicates open water, white indicates high sea ice concentration, and turquoise indicates loosely packed sea ice. The black circle at the North Pole results from an absence of data as the satellite does not make observations that far north. Three contour lines appear on this image. The red line is the 2007 minimum, as of September 15, about the same time the record low was reached, and it almost exactly fits the sea ice observed by AMSR-E. The green line indicates the 2005 minimum, the previous record low. The yellow line indicates the median minimum from 1979 to 2000.

  20. Global ice sheet modeling

    SciTech Connect

    Hughes, T.J.; Fastook, J.L.

    1994-05-01

    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed.

  1. Antarctic stratospheric ice crystals

    SciTech Connect

    Goodman, J. ); Toon, O.B.; Pueschel, R.F.; Snetsinger, K.G. ) Verma, S. )

    1989-11-30

    Ice crystals were replicated over the Palmer Peninsula at approximately 72{degree}S on six occasions during the 1987 Airborne Antarctic Ozone Experiment. The sampling altitude was between 12.5 and 18.5 km (45-65 thousand ft pressure altitude) with the temperature between 190 and 201 K. The atmosphere was subsaturated with respect to ice in all cases. The collected crystals were predominantly solid and hollow columns. The largest crystals were sampled at lower altitudes where the potential temperature was below 400 K. While the crystals were larger than anticipated, their low concentration results in a total surface area that is less than one tenth of the total aerosol surface area. The large ice crystals may play an important role in the observed stratospheric dehydration processes through sedimentation. Evidence of scavenging of submicron particles further suggests that the ice crystals may be effective in the removal of stratospheric chemicals.

  2. 2. POWERHOUSE FOREMAN'S BUNGALOW. CONTEXT VIEW FROM HILL ABOVE GARAGE ...

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

    2. POWERHOUSE FOREMAN'S BUNGALOW. CONTEXT VIEW FROM HILL ABOVE GARAGE SHOWING NORTHEAST AND NORTHWEST FACADES. VIEW TO SOUTH-SOUTHEAST. - Thompson Falls Hydroelectric Project, Power Foreman's Bungalow, On island between Forebay Channel & ClarkFord River, Thompson Falls, Sanders County, MT

  3. Blue Hills Regional Grad Fulfills Dream, Becomes Astronaut

    ERIC Educational Resources Information Center

    Bass, Judy

    2012-01-01

    This article features Scott D. Tingle, a former career and technical education (CTE) student who always aimed high. November 4, 2011 marked the official culmination of a cherished, virtually lifelong dream of his--becoming an astronaut. It was a goal he had in mind even when he was a high school student in the 1980s at Blue Hills Regional…

  4. 1. Historic American Buildings Survey Joseph Hill's Photograph Copy of ...

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

    1. Historic American Buildings Survey Joseph Hill's Photograph Copy of Original Photograph May5, 1936 SOUTH ELEVATION 1352 W.WASHINGTON BLVD. -1362 CHICAGO, ILLINOIS. - Chicago Ironwork, William M. Strong Estate (Cast Iron House & Gate), 1352 West Washington Boulevard, Chicago, Cook County, IL

  5. SummerHill Homes, San Francisco Bay Area, Fremont, California

    SciTech Connect

    2006-10-01

    Building America fact sheet on SummerHill Homes of Northern California. The Villa Savona Homes in Fremont, California were built using 15% fly ash in concrete, engineered lumber for floors, high efficiency windows with Low-emissivity (Low-E) glass, and fi

  6. Lost Hills Field Trial - incorporating new technology for resevoir management

    NASA Technical Reports Server (NTRS)

    Fielding, E. J.; Brink, J. L.; Patzek, T. W.; Silin, D. B.

    2002-01-01

    This paper will discuss how Chevron U.S.A. Production Company is implementing a field trial that will use Supervisory Control and Data Acquisition (SCADA)on injection wells, in conjunction with satellite images to measure ground elevation changes, to perform real-time resevoir management in the Lost Hills Field.

  7. Mineralogy of the Pahrump Hills Region, Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    Rampe, E. B.; Ming, D. W.; Vaniman, D. T.; Blake, D. F.; Chipera, S. J.; Morris, R. V.; Bish, D. L.; Cavanagh, P. D.; Achilles, C. N.; Bristow, T. F.; Morrison, S. M.; Treiman, A. H.; Downs, R. T.; Farmer, J. D.; Crisp, J. A.; Fendrich, K.; Morookian, J. M.

    2015-01-01

    The Pahrump Hills region of Gale crater is a approximately 12 millimeter thick section of sedimentary rocks in the Murray formation, interpreted as the basal geological unit of Mount Sharp. The Mars Science Laboratory, Curiosity, arrived at the Pahrump Hills in September, 2014, and performed a detailed six-month investigation of the sedimentary structures, geochemistry, and mineralogy of the area. During the campaign, Curiosity drilled and delivered three rock samples to its internal instruments, including the CheMin XRD/XRF. The three targets, Confidence Hills, Mojave 2, and Telegraph Peak, contain variable amounts of plagioclase, pyroxene, iron oxides, jarosite, phyllosilicates, and X-ray amorphous material. Hematite was predicted at the base of Mount Sharp from orbital visible/near-IR spectroscopy, and CheMin confirmed this detection. The presence of jarosite throughout Pahrump Hills suggests the sediments experienced acid-sulfate alteration, either in-situ or within the source region of the sediments. This acidic leaching environment is in stark contrast to the environment preserved within the Sheepbed mudstone on the plains of Gale crater. The minerals within Sheepbed, including Fe-saponite, indicate these sediments were deposited in a shallow lake with circumneutral pH that may have been habitable.

  8. Project Hill-Climb: Drafting and Design in Motion

    ERIC Educational Resources Information Center

    Crowl, William F.

    2008-01-01

    This article describes the Hill-Climb project of a second level Computer-Aided Drafting and Design (CADD) class. The author primarily designed the activity to increase student understanding of the assembly drawing process and its components. The emphasis on problem solving adds a dimension that can aid students in their other classes as well. By…

  9. Dynamics of Liquefaction during the 1987 Superstition Hills, California, Earthquake

    NASA Astrophysics Data System (ADS)

    Holzer, T. L.; Youd, T. L.; Hanks, T. C.

    1989-04-01

    Simultaneous measurements of seismically induced pore-water pressure changes and surface and subsurface accelerations at a site undergoing liquefaction caused by the Superstition Hills, California, earthquake (24 November 1987; M = 6.6) reveal that total pore pressures approached lithostatic conditions, but, unexpectedly, after most of the strong motion ceased. Excess pore pressures were generated once horizontal acceleration exceeded a threshold value.

  10. Managing the Theatre Facility at Smoky Hill High School.

    ERIC Educational Resources Information Center

    Pearl, Michael

    1989-01-01

    Discusses the management of a school theater facility. Discusses the role of the theater manager at Smoky Hill High School. Discusses the creation of the plan to oversee the operation and scheduling of the theater facility. Includes a copy of the contract form for using the theater. (SR)

  11. 268. Dennis Hill, Photographer April 1998 DETAIL VIEW FROM LOWER ...

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

    268. Dennis Hill, Photographer April 1998 DETAIL VIEW FROM LOWER DECK OF TRUSS VERTICAL AND UPPER DECK FLOOR BEAM CONNECTION AT PIER E-3, FACING NORTH. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  12. Evaluation of a Variable Rate Irrigating Hill-Seeder

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variable rate irrigating hill-seeder is a drought-alleviating and water-saving agricultural machine that can adjust water application automatically according to the soil moisture content and realize the synchronization between water and seeds through photoelectric-detecting technology. The objecti...

  13. The Ocean Hill-Brownsville School Project: A Profile.

    ERIC Educational Resources Information Center

    Wielk, Carol A.

    Ocean Hill-Brownsville was one of the three projects established by the New York City Board of Education to experiment with the reality of community participation. In time, much of the early optimism of community planners was dampened. The Board of Education's procrastination and its unwillingness to develop guidelines prior to the initiation of…

  14. 1. Overall view of the cloverleaf from a hill near ...

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

    1. Overall view of the cloverleaf from a hill near the southwest quadrant looking toward the northeast over the southwest leaf and southwest ramp. Bridge no. 5820 in near the center of the photograph. - Cloverleaf Interchange, Junction of Trunk Highways 52, 3, & 55, Inver Grove Heights, Dakota County, MN

  15. 64. VIEW OF EAST LORING LAKE LOOKING WEST FROM HILL ...

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

    64. VIEW OF EAST LORING LAKE LOOKING WEST FROM HILL BEHIND BUILDING 345 (ENTRY CONTROL BUILDING) IN STORAGE AREA, WITH BUILDING 1026 (BASE SPARES AREA WATER TOWER) IN DISTANCE. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

  16. Ten Tips for Higher Education Leaders: The Capitol Hill Perspective.

    ERIC Educational Resources Information Center

    Ford, William D.

    1990-01-01

    Suggestions to college administrators include realize that the essential lubricant of politics on Capitol Hill is relations of trust, confidence, and familiarity; bring solutions as well as problems to legislators; talk to members on the committee handling the issue of concern; help friends get reelected. (MLW)

  17. 77 FR 17402 - Black Hills National Forest Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-26

    ... forest issues such as forest plan revisions or amendments, forest health including fire management and..., Black Hills National Forest, in the wake of increasingly severe and intense wild fires and mountain pine... Plan, a priority following the major fires including the 86,000 acre Jasper Fire in 2000; 2. A...

  18. Possible Late Quaternary faulting in the Benton Hills, southeastern Missouri

    SciTech Connect

    Palmer, J.R.; Hoffman, D. . Dept. of Natural Resources)

    1993-03-01

    Geologic mapping in the 1930's by Dan Stewart and Lyle McManamy identified numerous faults in the Thebes Gap area of the Benton Hills, including two post-late Quaternary faults (max. of 10 m displacement) along the southeastern escarpment. Recent geologic mapping (Richard Harrison, pers. comm.) suggests dextral strike-slip displacement on most of these faults; some deformation post-dates the Pliocene-Pleistocene Mounds gravel. Small historical earthquake epicenters have been recorded in the Benton Hills area. Review of these data and analysis of the geologic and structural relationships to small- and large-scale drainage and alluvial features suggest tectonic control of the southeastern escarpment of the Benton Hills. The authors propose the coincidence of geologic structures and landforms resembles tectonically active alluvial basin margins, with the Benton Hills southeastern margin representing a fault block uplift escarpment. Future seismic reflection, drilling and trenching studies are planned to determine if the escarpment is fault controlled and of recent origin.

  19. 304. Dennis Hill, Photographer May 1998 VIEW ALONG UPPER DECK ...

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

    304. Dennis Hill, Photographer May 1998 VIEW ALONG UPPER DECK AT AT DECK TRUSS SPANS, WITH THROUGH TRUSS SPANS AND YERBA BUENA ISLAND IN BACKGROUND, FACING WEST-SOUTHWEST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  20. Ancient granite gneiss in the Black Hills, South Dakota

    USGS Publications Warehouse

    Zartman, R.E.; Norton, J.J.; Stern, T.W.

    1964-01-01

    Granite gneiss, with an age of approximately 2.5 billion years, in the Black Hills, South Dakota , provides a link betweeen ancient rocks in western Wyoming and Montana and in eastern North and South Dakota and Minnesota. The discovery suggests that early Precambrian rocks covered an extensive area in northcentral United States and were not restricted to several small nuclei.