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Sample records for northern anthracite field

  1. Water-quality trends for a stream draining the Southern Anthracite Field, Pennsylvania

    USGS Publications Warehouse

    Cravotta, C.A.; Bilger, M.D.

    2001-01-01

    Stream flow, chemical and biological data for the northern part of Swatara Creek, which drains a 112 km2 area in the Southern Anthracite Field of eastern Pennsylvania, indicate progressive improvement in water quality since 1959, after which most mines in the watershed had been flooded. Drainage from the flooded mines contributes substantially to base flow in Swatara Creek. Beginning in 1995, a variety of treatment systems and surface reclamation were implemented at some of the abandoned mines. At Ravine, Pa., immediately downstream of the mined area, median SO4 concentration declined from about 150 mg l-1 in 1959 to 75 mg l-1 in 1999 while pH increased from acidic to near-neutral values (medians: c. pH 4 before 1975; c. pH 6 after 1975). Fish populations rebounded from non-existent during 1959-1990 to 21 species identified in 1999. Nevertheless, recent monitoring indicates (1) episodic acidification and elevated concentrations and transport of Fe, Al, Mn, and trace metals during storm flow; (2) elevated concentrations of Fe, Mn, Co, Cu, Pb, Ni, and Zn in streambed sediments relative to unmined areas and to toxicity guidelines for aquatic invertebrates and fish; and (3) elevated concentrations of metals in fish tissue, notably Zn. The metals are ubiquitous in the fine fraction (<0.063 mm) of bed sediment in mining-affected tributaries and the main stem of Swatara Creek. As a result of scour and transport of streambed deposits, concentrations of suspended solids and total metals in the water column are correlated, and those for storm flow typically exceed base flow. Nevertheless, the metals concentrations are poorly correlated with stream flow because concentrations of suspended solids and total metals typically peak prior to peak stream stage. In contrast, SO4, specific conductance and pH are inversely correlated with stream flow as a result of dilution of poorly buffered stream water with weakly acidic storm runoff derived mainly from low-pH rainfall. Declines in

  2. Process for separating anthracite coal from impurities

    SciTech Connect

    Stiller, D.W.; Stiller, A.H.

    1985-05-06

    A process is described for separating a first mixture including previously mined anthracite coal, klinker-type cinder ash and other refuse consisting of: a. separating the first mixture to produce a refuse portion and a second mixture consisting of anthracite and klinker-type cinder ash, b. reducing the average particle size in the second mixture to a uniform size, c. subjecting the second mixture to a separating magnetic field to produce a klinker-type cinder ash portion and an anthracite coal portion.

  3. Quality of water in mines in the Western Middle Coal Field, Anthracite Region, east-central Pennsylvania

    USGS Publications Warehouse

    Reed, L.A.; Beard, M.M.; Growitz, D.J.

    1987-01-01

    The quality of mine water in the 75 sq-mi Western Middle anthracite field, Pennsylvania was determined by sampling discharges and boreholes at 60 abandoned and flooded mines during 1975-78. The Vulcan-Buck Mountain mine, east-northeast of Mahanoy City, contains an estimated 6,100 acre-ft of water with a specific conductance of 380 to 460 micromhos and a pH of 4.4 to 4.6 units. Twenty-two mines are in a 15-sq mi area between Mahanoy City and Girardville, all of which closed prior to 1958. Seven of these mines in the Mahanoy Basin may contain 30,000 acre-ft of water. Specific conductance ranges from 630 micromhos in the Tunnel mine to 1,800 micromhos in the Gilberton mine. Fifteen of these mines are in the Shenandoah complex; specific conductance ranges from 240 to 310 micromhos in mines in the eastern end of the complex to 2,400 micromhos in the western end. The specific conductance of water in 25 mines in the Mount Carmel-Shamokin area ranges from 460 to 980 micromhos. The North Franklin mine near Trevorton contains about 4,900 acre-ft of water with a specific conductance of about 1,100 micromhos. (USGS)

  4. Electrolytic oxidation of anthracite

    USGS Publications Warehouse

    Senftle, F.E.; Patton, K.M.; Heard, I.

    1981-01-01

    An anthracite slurry can be oxidized only with difficulty by electrolytic methods in which aqueous electrolytes are used if the slurry is confined to the region of the anode by a porous pot or diaphragm. However, it can be easily oxidized if the anthracite itself is used as the anode. No porous pot or diaphragm is needed. Oxidative consumption of the coal to alkali-soluble compounds is found to proceed preferentially at the edges of the aromatic planes. An oxidation model is proposed in which the chief oxidants are molecular and radical species formed by the electrolytic decomposition of water at the coal surface-electrolyte interface. The oxidation reactions proposed account for the opening of the aromatic rings and the subsequent formation of carboxylic acids. The model also explains the observed anisotropic oxidation and the need for the porous pot or diaphragm used in previous studies of the oxidation of coal slurries. ?? 1981.

  5. Integrated processing of anthracite into sorption materials

    SciTech Connect

    Sych, N.V.; Kartel, N.T.; Nikolaichuk, A.D.; Strelko, V.V.; Tsyba, N.N.; Denisovich, V.A.

    2006-05-15

    The possibility of using anthracite to produce activated carbon in the form of microporous and mesoporous anthracite, a cation exchanger, and composite sorption materials was analyzed and the porometric properties of a variety of sorption materials based on anthracite from the Donets coal basin were studied. A flowsheet for integrated processing of anthracite to give a set of four products was composed.

  6. Anthracite: A promising new target for coalbed methane exploration

    SciTech Connect

    Murray, D.K.

    1996-06-01

    Until recently, anthracite was not considered to constitute a viable reservoir for coalbed methane production. However, in 1994 commercial rates of methane were recovered from Permo-Carboniferous anthracites in the southern part of the North China Basin complex, in Henan and Shanxi Provinces, People`s Republic of China. During production tests of limited duration, shallow (approximately 1,200 to 1,600 ft) vertical wells flowed at rates exceeding 250 Mcf plus 200 bbls water per day. The coal in these two areas ranges from semi-anthracite to meta-anthracite, with vitrinite reflectances (R{sub o}) varying from 2.4 to 6.6 percent. In-situ gas contents of cored coals are as high as 1,000 s.c.f./short ton. The produced gas consists of approximately 95 percent methane, with traces of CO{sub 2} and other gases. Aggregate coal thickness in both areas is from 35 to 60 ft; some individual beds range from 10 to 20 ft in thickness. Cores of these anthracites are described as fractured and friable, exhibiting fair to good cleat development. These deposits occur in geologically complex areas within a zone of intersecting major tectonic elements that is characterized by high geothermal gradients. An untested but highly prospective anthracite deposit occurs in the South Wales Coal Basin, United Kingdom. Detailed, innovative research underway at the University of Wales, Cardiff, in this deformed Variscan foreland basin is focused on such topics as thrust-related permeability of anthracite and its potential control over coalbed methane production. The highest rank coal and the highest measured gas contents of cores (more than 850 s.c.f./short ton) in the U.K. are found in the northwestern part of the South Wales coal field.

  7. Reactivities of heat-treated anthracites

    SciTech Connect

    Ulanovskii, M.L.; Men'shikova, S.D.; Zingerman, Yu.V.

    1984-01-01

    Anthracites were selected and grouped from various Donbass mines in order to evaluate the effects of rank, ash and sulphur on reactivity. It was found that the rank of low-ash and low- sulphur anthracite has little effect on reactivity in the normal range of 1200-1600 C. Increased sulphur appreciably increases the chemical activity of heat-treated anthracite. From the point of view of carbon electrode manufacture it is important to find the optimum high-sulphur anthracite.

  8. Use of anthracite in the foundry industry

    SciTech Connect

    Bethray, A.

    1994-12-31

    Anthracite has been used for smelting iron in North America for nearly 200 years and is still used today in cupolas. Environmental and market factors contribute to continued cost increases in foundry coke that will continue in the future. This paper reviews the availability, quality and properties of anthracite and considers some of the differences in operation when using anthracite in place of coke.

  9. Anthracite firing -- Largest steam generators

    SciTech Connect

    Brower, P.; Winkin, J.; Changqin, G.

    1998-07-01

    The size and scope of the Hanfeng Power Plant is a large undertaking by any definition. It is progressing very well with good coordination and cooperation of all those involved. Start-up is scheduled for the first unit in the year 2000 with the second unit following by eight months. The boiler island scope covers all equipment and structural steel from the bunkers to the stack. This includes the world's two largest anthracite fired boilers burning a blend of very low volatile Chinese anthracite and lean coal (bituminous). The coal blending is designed to maximize the use of the local anthracite coal. This is done by controlled blending at the entrance to the large FW D12D ball mills. Scaling up from earlier extensive experience with arch fired boilers is reviewed as well as key features of the Hanfeng boilers each of which are capable of generating 563 kg/s of steam at 540.8 C and 175 bar (equivalent to 717 MW of turbine/generator output). The design of the boiler and related equipment for the Hanfeng project has been the subject of in-depth reviews by independent engineers representing the banks to assure reliability of the boiler to support the economic model. It has been shown that FW's extensive experience burning anthracite coals has justified the scaling up of the various components to meet the requirements of the specification. This experience is based on operating similar type anthracite arch fired boilers with fuel blends that are comparable to the coals to be supplied for the Hanfeng project. The materials and equipment for the Hanfeng boiler island are being supplied on a multi-national basis in support of the various requirements of the financing institutions involved. The overall design has been finalized and the detail design is well underway. Most of the large critical components are already in manufacturing.

  10. Laboratory and field evaluation of a flushable oxic limestone drain for treatment of net-acidic drainage from a flooded anthracite mine, Pennsylvania, USA

    USGS Publications Warehouse

    Cravotta, C.A.

    2008-01-01

    This paper demonstrates the use of dissolution-rate data obtained in the laboratory to indicate the potential quality of effluent from a field-scale oxic limestone drain (OLD) treatment system for neutralization of dilute acidic mine drainage (AMD). Effluent from the Reevesdale Mine South Dip Tunnel, a large source of AMD and base flow to the Wabash Creek and Little Schuylkill River in the Southern Anthracite Coalfield of east-central Pennsylvania, is representative of AMD with low concentrations but high loadings of dissolved Fe, Al and other metals because of a high flow rate. In January 2003, rapid neutralization of the AMD from the Reevesdale Mine was achieved in laboratory tests of its reaction rate with crushed limestone in closed, collapsible containers (Cubitainers). The tests showed that net-alkaline effluent could be achieved with retention times greater than 3 h and that effluent alkalinities and associated dissolution rates were equivalent for Fe(OH)3-coated and uncoated limestone. On the basis of the laboratory results, a flushable OLD containing 1450 metric tons of high-purity calcitic limestone followed by two 0.7-m deep wetlands were constructed at the Reevesdale Mine. During the first year of operation, monthly data at the inflow, outflow and intermediate points within the treatment system were collected (April 2006-2007). The inflow to the treatment system ranged from 6.8 to 27.4 L/s, with median pH of 4.7, net acidity of 9.1 mg/L CaCO3, and concentrations of dissolved Al, Fe and Mn of 1.0, 1.9 and 0.89 mg/L, respectively. The corresponding effluent from the OLD had computed void-volume retention times of 4.5-18 h, with median pH of 6.6, net acidity of -93.2 mg/L CaCO3, and concentrations of dissolved Al, Fe and Mn of <0.1, 0.08 and 0.52 mg/L, respectively. The wetlands below the OLD were effective for retaining metal-rich solids flushed at monthly or more frequent intervals from the OLD, but otherwise had little effect on the effluent quality

  11. Anthracite culm fired fluidized-bed boiler

    SciTech Connect

    Lentz, E.C.

    1984-01-01

    The author describes a fluidised-bed boiler that has been designed by FluiDyne Engineering Corp. for the combustion of anthracite culm, a material containing about 40% ash and consisting of coal particles embedded in mineral matter. There are some 900 million tons of anthracite culm in northeast Pennsylvania within easy reach of many large metropolitan areas. It is estimated that the material can be used economically within a distance of 200 miles.

  12. Downflow limestone beds for treatment of net-acidic, oxic, iron-laden drainage from a flooded Anthracite Mine, Pennsylvania, USA: 1. Field evaluation

    USGS Publications Warehouse

    Cravotta, C.A.; Ward, S.J.

    2008-01-01

    Passive-treatment systems that route acidic mine drainage (AMD) through crushed limestone and/or organic-rich substrates have been used to remove the acidity and metals from various AMD sources, with a wide range of effects. This study evaluates treatment of net-acidic, oxic, iron-laden AMD with limestone alone, and with organic-rich compost layered with the limestone. In the fall of 2003, a treatment system consisting of two parallel, 500-m2 downflow cells followed by a 400-m2 aerobic settling pond and wetland was installed to neutralize the AMD from the Bell Mine, a large source of AMD and baseflow to the Schuylkill River in the Southern Anthracite Coalfield, in east-central Pennsylvania. Each downflow cell consisted of a lower substrate layer of 1,090 metric tons (t) of dolomitic limestone (60 wt% CaCO3) and an upper layer of 300 t of calcitic limestone (95 wt% CaCO3); one of the downflow cells also included a 0.3 m thick layer of mushroom compost over the limestone. AMD with pH of 3.5-4.3, dissolved oxygen of 6.6-9.9 mg/L, iron of 1.9-5.4 mg/L, and aluminum of 0.8-1.9 mg/L flooded each cell to a depth 0.65 m above the treatment substrates, percolated through the substrates to underlying, perforated outflow pipes, and then flowed through the aerobic pond and wetland before discharging to the Schuylkill River. Data on the flow rates and chemistry of the effluent for the treatment system indicated substantial neutralization by the calcitic limestone but only marginal effects from the dolomitic limestone or compost. Because of its higher transmissivity, the treatment cell containing only limestone neutralized greater quantities of acidity than the cell containing compost and limestone. On average, the treatment system removed 62% of the influent acidity, 47% of the dissolved iron, 34% of the dissolved aluminum, and 8% of the dissolved manganese. Prior to treatment of the Bell Discharge, the Schuylkill River immediately below its confluence with the discharge had p

  13. 30 CFR 716.5 - Anthracite coal mines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Anthracite coal mines. 716.5 Section 716.5... PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.5 Anthracite coal mines. (a) Permittees of anthracite surface coal mining and reclamation operations in those States where the mines are regulated by...

  14. 30 CFR 716.5 - Anthracite coal mines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Anthracite coal mines. 716.5 Section 716.5... PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.5 Anthracite coal mines. (a) Permittees of anthracite surface coal mining and reclamation operations in those States where the mines are regulated...

  15. 30 CFR 716.5 - Anthracite coal mines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Anthracite coal mines. 716.5 Section 716.5... PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.5 Anthracite coal mines. (a) Permittees of anthracite surface coal mining and reclamation operations in those States where the mines are regulated...

  16. 30 CFR 716.5 - Anthracite coal mines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Anthracite coal mines. 716.5 Section 716.5... PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.5 Anthracite coal mines. (a) Permittees of anthracite surface coal mining and reclamation operations in those States where the mines are regulated...

  17. 30 CFR 716.5 - Anthracite coal mines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Anthracite coal mines. 716.5 Section 716.5... PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.5 Anthracite coal mines. (a) Permittees of anthracite surface coal mining and reclamation operations in those States where the mines are regulated...

  18. Giant gas field of northern West Siberia

    SciTech Connect

    Grace, J.D.; Hart, G.F.

    1986-06-01

    The 66 fields discovered since the 1960s in the northern West Siberian basin contain at least 22 trillion m/sup 3/ (777 tcf) of proved gas, almost one-third of the world's reserves. Half of these fields are giants (> 85 billion m/sup 3/ or 3000 bcf of reserves). These include the largest and second-largest gas fields in the world-Urengoy (8.099 trillion m/sup 3/ or 286 tcf of gas) and Yamburg (4.81 trillion m/sup 3/ or 170 tcf of gas)-as well as most of the other ten largest gas fields in the world. The West Siberian basin occupies a 3.4-million km/sup 2/ (1.31-million mi/sup 2/) arctic lowland immediately east of the Ural Mountains, extending north under the Kara Sea. It is a composite basin, with Mesozoic-Cenozoic basin fill on top of a Paleozoic basin that overlies a crystalline Archean-Proterozoic framework. The productive zones in the northern basin are principally in the Neocomian section (at an average depth of 2800m or 9200 ft) and the Cenomanian section (at an average depth of 2800 m or 9200 ft) and the Cenomanian section (at an average depth of 1100 m or 3600 ft). The former contains reservoirs with gas, condensate, and oil; the latter contains two-thirds of the region's gas. Gas in Cenomanian reservoirs is almost pure methane. Hydrocarbons in Neocomian reservoirs were generated by thermal maturation of sapropelic organic matter contained principally in the Tithonian Bazhenov shale. Methane in the Cenomanian section appears to be a combination of thermogenic gas from the Bazhenov Suite (or deeper) and biogenic gas generated in the Cenomanian section itself, although workers disagree over how much gas came from each source. Continental glaciation during the Pleistocene may have been important in concentrating the methane in Cenomanian reservoirs.

  19. Hydroseeding on anthracite coal-mine spoils

    Treesearch

    Miroslaw M. Czapowskyj; Ross Writer

    1970-01-01

    A study was made of the performance of selected species of legumes, grasses, and trees hydroseeded on anthracite coal-mine spoils in a slurry of lime, fertilizer, and mulch. Hydroseeding failed on coal-breaker refuse, but was partially successful on strip-mine spoils.

  20. Porosity and sorption properties of activated carbons prepared from anthracite by steam-air activation

    SciTech Connect

    Sych, N.V.; Kartel, N.T.; Tsyba, N.N.; Strelko, V.V.; Nikolaichuk, A.D.; Mironyuk, T.I.

    2006-04-15

    Fundamental aspects of the steam-air activation of anthracite from Donets coal fields were studied. The effect of the flow rate of moistened air on the development of a porous structure and the sorption properties of the adsorbents obtained were examined.

  1. Maximizing the existing potential of new foreign markets for anthracite

    SciTech Connect

    Ziolkowski, L.W.; Ahn, Y.K.; Hong, S.P.

    1988-09-01

    The major purposes of this report were to: (1) conduct an in-depth survey of both the technical and marketing problems in the United States Anthracite Industry (predominately in Northeastern Pennsylvania); and (2) make recommendations in areas of technical R and D needs that will enhance the United States export of anthracite to foreign markets (especially Korea). The report identifies various anthracite culm drying and other coal utilization concepts; recommends several anthracite utilization configurations which appear to be the most suitable to the Korean market and a sensitivity analysis on these configurations; and identifies several solutions to resolve some of the problems which were identified relative to: (a) reducing the price of exporting anthracite; (b) the producers quality control activities which relate to meeting the Korean specifications and generally improving the understanding on the contract terms that relate to the encouragement of long term commitments of anthracite by Korea. 33 refs., 23 figs., 33 tabs.

  2. Developing anthracite coal water slurry fuel. Final report

    SciTech Connect

    Simmon, F.J.; Keller, D.V.; Marino, J.; Keller, D.S.; Ask, T.E.

    1993-09-01

    Public law has directed the Department of Defense (DOD) to increase the use of coal, particularly anthracite, at steam generating facilities. This study evaluates the feasibility of producing slurry fuel from anthracite coal and examines the combustion characteristics of the anthracite/water fuel slurry. The T-Process, a proprietary process developed by Otisca Industries, Ltd., Syracuse, NY, was used to produce anthracite-based coal water slurries for testing and combustion. Although it is feasible to manufacture anthracite water fuel, the slurries used in this research would not burn well without substantial amounts of natural gas cofiring. Stable combustion with reduced support fuel can probably be achieved by chemically or physically modifying the factors that affect combustion. Additional research to determine the differences between anthracite and bituminous slurries, to increase the residence time for anthracite slurries, and to manufacture slurries with oil rather than water needs to be conducted to help the DOD meet anthracite purchase/consumption targets. Coal, Combustion, Coal water fuel, Anthracite coal.

  3. Anthracite coal supply for the 1981-1982 winter. [USA

    SciTech Connect

    Not Available

    1981-09-18

    This report focuses on some of the problems affecting the anthracite industry and consumers in the northeastern States, State and industry actions since the 1980-81 shortage, and the outlook for the winter of 1981-82. It also includes information on anthracite exports to foreign countries and the Department of Defense (DOD) facilities in the Federal Republic of Germany, Federal research and development efforts to use anthracite in industrial boilers, and the actions the State of Pennsylvania has taken to encourage the use of anthracite in municipal buildings.

  4. The aspen-gray birch forests of the Anthracite Region

    Treesearch

    C. F. Burnham; M. J. Ferree; F. E. Cunningham

    1947-01-01

    This paper is a progress report of forest research in the Anthracite Region by personnel of the Station's branch at Kingston, Pa. It is the fourth in a series of seven reports dealing with the principal forest types in the Anthracite Region.

  5. Properties of metal-anthracite contacts at high flow densities

    SciTech Connect

    Okorochkov, A.I.; Pavlinov, A.B.; Polyl'nyi, V.Ya.

    1983-01-01

    Measurement of the volt-ampere characteristics of metal-anthracite contacts in the pulsating mode and under isothermal conditions showed a loss of linearity of potential distribution in the contact regions in the anthracite, possibly due to the injection of free charge carriers from these contacts.

  6. Properties of metal-anthracite contacts at high flow densities

    SciTech Connect

    Okorochkov, A.I.; Pavlinov, A.B.; Posyl'nyi, V.Ya.

    1983-01-01

    The volt-ampere characteristics (VAC) of metal-anthracite contacts have been measured under isothermal conditions in the pulsed regime. A deviation from linearity of the distribution of potential in the regions of anthracite adjacent to the contacts has been detected which can be explained by the injection of free charge carriers from the contacts.

  7. Coal: Pennsylvania anthracite 1978. Energy data report

    SciTech Connect

    Watson, W.

    1980-10-01

    Production of Pennsylvania Anthracite in 1978 decreased 14.1 percent or 824 thousand short tons from the 1977 figure of 5861 thousand short tons to 5037 thousand short tons. Buckwheat No. 1 and smaller sizes accounted for 3768 thousand short tons or 75 percent of production. Pea and larger sizes accounted for 1259 thousand short tons or 25 percent of production. Average price per ton (f.o.b. preparation plant) increased 1.1 percent from the 1977 figure of $34.86 to $35.25. Productivity declined 6.6 percent from 6.97 to 6.51 short tons per miner per day. Domestic distribution of anthracite in 1978 totaled 3895 thousand short tons or 77.3 percent of production. Of this amount, 1597 thousand short tons or 41 percent went to residential and commercial consumers, 1064 thousand short tons or 27.3 percent went to electric utilities, 748 thousand short tons or 19.2 percent went to other industrial users, 476 thousand short tons or 12.2 percent went to the iron and steel industry, and 10 thousand short tons or 0.3 percent was consumed at mining operations. US exports of anthracite in 1978 totaled 1142 thousand short tons or 22.7 percent of production. Exports to Canada were 405 thousand short tons, to South Korea - 331 thousand short tons, and to US military forces in West Germany - 276 thousand short tons. The Canadian, Korean, and German exports accounted for 1012 thousand short tons or 88.6 percent of all exports in 1978.

  8. Polarization of anthracite electrodes in electrolyte solutions

    SciTech Connect

    A.N. Lopanov; E.V. Blaido; O.V. Smirnova

    2007-10-15

    The regularities of the polarization of anthractie electrodes for the liberation of hydrogen from electrolyte (potassium chloride and hydrogen chloride) solutions were found, and electrode processes occurring at the surface of coals in the Fe{sup 2+}/Fe{sup 3+} redox system were studied. It was found that the deviations of standard electrode potentials from the equilibrium values of redox systems depend on the exchange current densities of electrochemical processes occurring at the surface of coal matter. Low transfer coefficients (0.04-0.051) for the discharge reaction of hydrogen ions on anthracites indicate that the reaction occurs under conditions close to those of an activationless process.

  9. Anthracite coal supply for the 1981-1982 winter

    SciTech Connect

    Peach, J.D.

    1981-09-18

    This report contains a letter addressed to the Chairman of the Subcommittee on Energy and Mineral Resources in which findings on the potential for anthracite to become an effective component in meeting US energy needs are presented. Some of the problems facing the anthracite industry and consumers in the northeastern states, state and industry actions since the 1980 shortage, and the outlook for the winter of 1982 are addressed. Information was obtained on anthracite exports to foreign countries and to the DOD facilities in the Federal Republic of Germany. Development efforts to use anthracite in industrial boilers and the actions that the state of Pennsylvania has taken to encourage the use of anthracite in municipal buildings are also discussed. (DMC)

  10. Novel approach to the production of graphite from anthracite

    SciTech Connect

    Atria, J.V.; Zeng, S.; Rusinko, F. Jr.

    1994-12-31

    Currently the carbon/graphite industry uses petroleum coke as the main filler constituent in the manufacture of graphite. Anthracite has been successfully used as fillers for amorphous carbon electrodes, but has not been used in the production of graphite electrodes because of its non-graphitizable structure. In the present project, a unique approach to make graphite from anthracite, focused on modifying anthracite`s precursor structure by adding a hydrogen-donating substance, has been conducted. This approach is based on two major hypotheses. First, a supply of donatable or transferable hydrogen is needed for the hydrogen-deficient anthracite structure to disrupt crosslink formation between aromatic structures within the coal. Secondly, an aromatic liquid medium is needed to help prevent electronic interactions between aromatic structures and provide the fluidity necessary for aromatic realignment into the graphite structure. Several hydrogen donors were investigated. 9,10-Dihydroanthracene showed the best ability to donate hydrogen to anthracite and also formed a highly anisotropic anthracene coke in the process. Phenanthrene was selected as the aromatic liquid medium. Both anthracene and phenanthrene have been found to he highly graphitizable. Although hydrogen was successfully donated to the anthracite, the hydrogen donation is believed to have only occurred at the surface and did not affect the internal structure of the coal. Because of the dependence of graphitizability on pore structure and the resistance of the internal coal structure to hydrogen donation, six anthracites were studied to determine their pore characteristics. Three of the anthracites, representing a variety of pore characteristics, were then selected to investigate the hydrogenation and subsequent graphitization of the anthracites treated with dihydroanthracene.

  11. Fine Anthracite Coal Washing Using Spirals

    SciTech Connect

    R.P. Killmeyer; P.H. Zandhuis; M.V. Ciocco; W. Weldon; T. West; D. Petrunak

    2001-05-31

    The spiral performed well in cleaning the coarse 8 x 16 mesh size fraction, as demonstrated by the Ep ranging from 0.091 to 0.177. This is in line with typical spiral performance. In addition, the presence of the coarser size fraction did not significantly affect spiral performance on the typical 16 x 100 mesh fraction, in which the Ep ranged from 0.144 to 0.250. Changes in solids concentration and flow rate did not show a clear correlation with spiral performance. However, for difficult-to-clean coals with high near-gravity material, such as this anthracite, a single-stage spiral cleaning such a wide size fraction may not be able to achieve the clean coal ash and yield specifications required. In the first place, while the performance of the spiral on the coarse 8 x 16 mesh fraction is good with regard to Ep, the cutpoints (SG50s) are high (1.87 to 1.92), which may result in a clean coal with a higher-than-desired ash content. And second, the combination of the spiral's higher overall cutpoint (1.80) with the high near-gravity anthracite results in significant misplaced material that increases the clean coal ash error. In a case such as this, one solution may be to reclean the clean coal and middlings from the first-stage spiral in a second stage spiral.

  12. 30 CFR 820.11 - Performance standards: Anthracite mines in Pennsylvania.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Performance standards: Anthracite mines in... STANDARDS-ANTHRACITE MINES IN PENNSYLVANIA § 820.11 Performance standards: Anthracite mines in Pennsylvania. Anthracite mines in Pennsylvania, as specified in section 529 of the Act, shall comply with its...

  13. 30 CFR 820.11 - Performance standards: Anthracite mines in Pennsylvania.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Performance standards: Anthracite mines in... STANDARDS-ANTHRACITE MINES IN PENNSYLVANIA § 820.11 Performance standards: Anthracite mines in Pennsylvania. Anthracite mines in Pennsylvania, as specified in section 529 of the Act, shall comply with its...

  14. 30 CFR 820.11 - Performance standards: Anthracite mines in Pennsylvania.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Performance standards: Anthracite mines in... STANDARDS-ANTHRACITE MINES IN PENNSYLVANIA § 820.11 Performance standards: Anthracite mines in Pennsylvania. Anthracite mines in Pennsylvania, as specified in section 529 of the Act, shall comply with its...

  15. 30 CFR 820.11 - Performance standards: Anthracite mines in Pennsylvania.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Performance standards: Anthracite mines in... STANDARDS-ANTHRACITE MINES IN PENNSYLVANIA § 820.11 Performance standards: Anthracite mines in Pennsylvania. Anthracite mines in Pennsylvania, as specified in section 529 of the Act, shall comply with its...

  16. 30 CFR 820.11 - Performance standards: Anthracite mines in Pennsylvania.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Performance standards: Anthracite mines in... STANDARDS-ANTHRACITE MINES IN PENNSYLVANIA § 820.11 Performance standards: Anthracite mines in Pennsylvania. Anthracite mines in Pennsylvania, as specified in section 529 of the Act, shall comply with its...

  17. Field guide to forest plants of northern Idaho

    Treesearch

    Patricia A. Patterson; Kenneth E. Neiman; Jonalea K. Tonn

    1985-01-01

    This field guide -- designed for use by people with minimal botanical training -- is an identification aid for nearly 200 plant species having ecological indicator value in northern Idaho forest habitat types. It contains line drawings, simplified taxonomic descriptions , characteristics tables, conspectuses, and keys. It emphasizes characteristics useful for field...

  18. Objective styles in northern field science.

    PubMed

    Kochan, Jeff

    2015-08-01

    Social studies of science have often treated natural field sites as extensions of the laboratory. But this overlooks the unique specificities of field sites. While lab sites are usually private spaces with carefully controlled borders, field sites are more typically public spaces with fluid boundaries and diverse inhabitants. Field scientists must therefore often adapt their work to the demands and interests of local agents. I propose to address the difference between lab and field in sociological terms, as a difference in style. A field style treats epistemic alterity as a resource rather than an obstacle for objective knowledge production. A sociological stylistics of the field should thus explain how objective science can co-exist with radical conceptual difference. I discuss examples from the Canadian North, focussing on collaborations between state wildlife biologists and managers, on the one hand, and local Aboriginal Elders and hunters, on the other. I argue that a sociological stylistics of the field can help us to better understand how radically diverse agents may collaborate across cultures in the successful production of reliable natural knowledge. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Physical property data on coarse anthracite waste. Report of investigations

    SciTech Connect

    Stewart, B.M.; Atkins, L.A.

    1983-07-01

    Since 1974, a large amount of data has been developed concerning the physical properties and stability characteristics of waste generated by the mining and preparation of bituminous coal. However, very little information has been developed on the properties and characteristics of anthracite waste. During this Bureau of Mines research project, coarse anthracite breaker refuse from five sites in eastern Pennsylvania was sampled and the physical properties, which indicate stability characteristics, were determined in the laboratory. Stability analyses were conducted on six theoretical anthracite waste embankments. These analyses show the effects on minimum safety factors of geometry, phreatic surface level, and physical properties.

  20. Standard test method for size of anthracite

    SciTech Connect

    Not Available

    1980-01-01

    This method covering screen analysis of anthracite is used to determine the percentage of undersize or oversize in ny given commercial size. The values stated in inch-pound units are to be regarded as the standard. Procedure, in case th coal is wet, air-dryit before screening. Determine the undersize first. For broken, egg, and stove sizes, up-end each piece by hand on the screen, to determine whether in any position it passes through the screen. For nut, pea, buckwheat, and rice sizes, shake the screens gently with a reciprocating horizontal motion, so as to avoid breakage ofthe coal, until practically no more coal will pass through the openings. Screen the coal in such increments as will allow the pieces to be in direct contact with the screen openings after the completion of the shaking of each increment.

  1. Graphene-like structure of activated anthracites

    NASA Astrophysics Data System (ADS)

    Hawelek, L.; Woznica, N.; Brodka, A.; Fierro, V.; Celzard, A.; Bulou, A.; Burian, A.

    2012-12-01

    The structure of a series of activated carbons prepared from anthracite by chemical activation has been studied using wide-angle x-ray scattering, molecular dynamics and Raman spectroscopy. The BET surface areas of the investigated samples are in the range 1500-3430 m2 g-1 and the average pore sizes vary from 0.75 to 1.35 nm. The diffraction measurements were carried out to a maximum value of the scattering vector Kmax = 22 Å-1. The obtained diffraction data have been converted to a real space representation in the form of the pair correlation function. The structure of the studied samples consists of one or two graphite-like layers, stacked without spatial correlations. The size of the ordered layer region is approximately 24 Å. The atomic arrangement within an individual layer has been described in terms of paracrystalline ordering, in which lattice distortions are propagated proportionally to the square root of inter-atomic distances. The paracrystalline structure has been simulated by introducing the Stone-Thrower-Wales, mono-vacancy and di-vacancy defects, randomly distributed in the network. These defects lead to the formation of a defected network with the presence of non-hexagonal rings in which distortion of the structure extends outside of a defect region. Computer generated structural models have been relaxed at room temperature using the reactive empirical bond order potential for intra-layer interactions and the Lennard-Jones potential for inter-layer interactions. For such generated models the structure factors and the pair correlation functions were computed. A good agreement between the simulation results and the experimental data in both reciprocal and real space provides evidence for the correctness of the proposed models. The Raman data support the validity of these models. Porosity of the activated anthracites is discussed in relation to their defective structure.

  2. Response of crownvetch planted on anthracite breaker refuse

    Treesearch

    Miroslaw M. Czapowskyj; John P. Mikulecky; Edward A. Sowa

    1968-01-01

    Lime applications were essential to establishment of crownvetch (Coronilla vuria L.) on coal breaker refuse in the Pennsylvania Anthracite Region, and mulch treatments were highly beneficial. Fertilizer applications had only slight effect on either establishment or growth.

  3. Three-Dimensional X-ray Reflections from Anthracite and Meta-Anthracite.

    PubMed

    Ergun, S; Mentser, M; O'donnell, H J

    1960-11-04

    Careful analysis of x-ray scattering intensities of demineralized metaanthracites and high-rank anthracites formed during the Pennsylvanian geological period has revealed the presence of three-dimensional (hkl) reflections of graphite, demonstrating unequivocally that coals graphitize with metamorphism. Graphitization has been observed also with a coal formed before the Cambrian period, much earlier than most coals. A significant degree of graphitization occurs by coalification when the graphite-like layers attain a size of 25 to 30 angstroms as compared to 100 A or more by the heat treatment of amorphous carbons.

  4. Coalcracker culture. Work and values in Pennsylvania anthracite, 1835-1935

    SciTech Connect

    Aurand, H.W.

    2003-07-01

    This book traces the evolution of a distinct regional culture in the anthracite coalfields of Pennsylvania. It begins by establishing the region's industrial and social context, before tracing the development of anthracite deep mining. Finally, the values fostered by the work of deep mining anthracite are examined.

  5. Advanced burner technology for low volatile coal and anthracite

    SciTech Connect

    Tigges, K.D.; Streffing, M.; Lisauskas, R.; Ake, T.

    1997-12-31

    Today China is one of the countries with the highest coal production. Approximately three quarters of the produced coal is high-volatile and medium-volatile hard coal and only about 20% is anthracite. However the actual portion of the anthracite used in power plants is even lower. The reason for this is not due to the low amount available, but to the difficulty of ensuring stable and reliable ignition and combustion of anthracite. Up to now, the so-called Downshot firing system has been used to fire difficult anthracite coals. The experience gained with this type of firing system is, however, far from satisfactory. The numerous difficulties in the plants of all manufactures have shown that attempts should be made to develop efficient burners to be able to use the simple, service-proved and reliable opposed-burner system. Deutsche Babcock started this work in the early 1980`s and developed a second generation low-NOx burner -- the DS burner -- which is also well suited for the combustion of anthracite. The development is based on state-of-the-art advanced computer simulation and full-scale combustion tests on a wide range of coals. Performance has been evaluated on coals with volatile matter content ranging from 50% down to as low as 5%. DS burners are characterized by extremely reliable and stable ignition which allows operation at low part loads even when firing difficult coal. The excellent flame stability of this burner is the reason why the complex Downshot firing system with its numerous disadvantages is no longer necessary and opposed burner system may be applied even for firing anthracite. The paper describes the development of the burner for difficult coals and explains the full scale combustion tests, the laboratory tests of the ignitability and compares these results with the computer simulation of the DS burner flame.

  6. The dissolution of an anthracite coal with perchloric acid

    SciTech Connect

    Hood, G.E.; Hyatt, A.G.; McGowan, C.W.

    1996-10-01

    Lignite coal, bituminous coal and several oil shales have previously been dissolved using perchloric acid of varying boiling point and subsequent oxidizing ability. These organic deposits generally dissolved between 150 and 160{degrees}C. This indicated that the aliphatic ether oxygen bond was being broken during the dissolution process. This dissolution process was performed on an anthracite coal because of the coal`s low oxygen content. The anthracite coal dissolved between 180 and 190{degrees}C making it similar to high-vol bituminous coal from New Zealand. Earlier work has indicated that carbon-carbon double bonds are being attacked during the dissolution process at the higher temperatures.

  7. 100 MW anthracite culm CFB small power producer

    SciTech Connect

    McKenzie, R. ); Wilhelm, B. . Power Systems Group)

    1988-01-01

    This paper discusses the development and design aspects of the St. Nicholas Cogeneration Project. The project is an anthracite culm-fired 80 MWe qualifying cogeneration facility. The project is privately financed, owned, and to be operated to produce process steam for commercial use along with cogenerating electricity for sale to the local utility. This paper highlights the details of the power sales agreement with Pennsylvania Power and Light Company, the development of the project for third-party financing, and the design considerations for fueling the facility with anthracite culm.

  8. Identification and mapping of coal refuse banks and other targets in the anthracite region

    NASA Technical Reports Server (NTRS)

    Borden, F. Y.; Thompson, D. N.; Lachowski, H. M.

    1973-01-01

    ERTS-1 MSS data covering parts of Pennsylvania's southern and eastern middle anthracite coal fields were studied to determine how well accumulations of coal refuse could be identified and mapped by computer analysis and processing. Spectral signatures of coal refuse targets were similar to water, but had higher reflectances in all channels. Relative reflectances were in the order 4 5 or = 6 7. Although no underflight photography was at hand to judge mapping success, correlation was made, with 1:24,000 scale U.S.G.S. maps dated 1947 and 1948. Coal refuse targets correlated well with existing maps.

  9. Cumulative impacts of oil fields on northern Alaskan landscapes

    USGS Publications Warehouse

    Walker, D.A.; Webber, P.J.; Binnian, Emily F.; Everett, K.R.; Lederer, N.D.; Nordstrand, E.A.; Walker, M.D.

    1987-01-01

    Proposed further developments on Alaska's Arctic Coastal Plain raise questions about cumulative effects on arctic tundra ecosystems of development of multiple large oil fields. Maps of historical changes to the Prudhoe Bay Oil Field show indirect impacts can lag behind planned developments by many years and the total area eventually disturbed can greatly exceed the planned area of construction. For example, in the wettest parts of the oil field (flat thaw-lake plains), flooding and thermokarst covered more than twice the area directly affected by roads and other construction activities. Protecting critical wildlife habitat is the central issue for cumulative impact analysis in northern Alaska. Comprehensive landscape planning with the use of geographic information system technology and detailed geobotanical maps can help identify and protect areas of high wildlife use.

  10. Inventory of federally-funded projects and programs related to anthracite

    SciTech Connect

    1980-06-01

    This report is a compilation of descriptions of federal projects and programs that are concerned in some way with anthracite. It is the first inventory of its type to be prepared. Among the projects and programs described are those completed in the latter half of 1979, those that are currently active, and others that will start soon. Of the 43 projects described, 8 involve research, development, and demonstration (RD and D) of technologies aimed at enhancing the use of anthracite or anthracite mining waste; 6 address environmental problems associated with anthracite mining or use; 9 provide information on the anthracite industry; 16 involve studies related to anthracite; and 4 are miscellaneous projects and programs. These projects and programs represent federal government expenditures of $27.1 million, excluding current military purchases of anthracite for use in European bases of $33.6 million, and US Bureau of Mines mined land demonstration and reclamation projects of $38.3 million.

  11. The white pine - oak forests of the anthracite region

    Treesearch

    C. F. Burnham; M. J. Ferree; F. E. Cunningham

    1947-01-01

    The white pine - oak forests in the Anthracite Region occupy approximately one-fifth of the forested area. They occur chiefly in the central and southern counties of the region and are characteristic of the fairly fertile agricultural sections in the rolling foothills. Sixty-nine percent are located in these farming areas, another 23 percent are in less accessible...

  12. Anthracite firing design for central stations: Ignition and emissions aspects

    SciTech Connect

    Garcia-Mallol, J.A.; Kukoski, A.E.; Winkin, J.P.

    1997-12-31

    The most successful technology for firing pulverized anthracite coals in central station steam generators has accumulated more than 12,000 MWe of ordered capacity worldwide, over half of which is already operational. These units burn coals with less than 14% volatile matter. A recent contract is the 2,100 MWe Yangcheng Power Plant, which will fire a southeast Shanxi anthracite having only 5% volatile matter. Foster Wheeler`s technology ensures self-ignition by integrating, in a double-arch fired, water-wall furnace: (1) partial refractory coverage of the walls, (2) venting of cold primary (coal transport) air, (3) hot gas entrainment at the beginning of the jet-flame. Fuel systems applied to anthracite coals will be reviewed, including the one for the ongoing Hanfeng project in Hebei, which consists of two 660 MWe arch-fired units. Alternative means to improve ignition will also be presented. In addition, emissions from anthracites are characterized, including the effect of an over-fire air design suitable for arch-fired furnaces.

  13. 30 CFR 75.404 - Exemption of anthracite mines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Exemption of anthracite mines. 75.404 Section 75.404 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting...

  14. 30 CFR 75.404 - Exemption of anthracite mines.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Exemption of anthracite mines. 75.404 Section 75.404 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting...

  15. 30 CFR 75.404 - Exemption of anthracite mines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Exemption of anthracite mines. 75.404 Section 75.404 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting...

  16. 30 CFR 75.404 - Exemption of anthracite mines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Exemption of anthracite mines. 75.404 Section 75.404 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting...

  17. 30 CFR 75.404 - Exemption of anthracite mines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Exemption of anthracite mines. 75.404 Section 75.404 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting...

  18. Assessment of new sources performance standards (NSPS) for anthracite-fired industrial boilers

    SciTech Connect

    Not Available

    1982-06-01

    Environmental Research and Technology, Inc. and Berger Associates, under separate contracts with the US Department of Energy, were requested to estimate the impact of various levels of industrial boiler new sources performance standards (NSPS) on potential future markets for anthracite use in industrial boilers and to analyze the impact of changes in anthracite use on the air quality, environment, and economics of the NE Pennsylvania anthracite region. The combined contractors' analyses presented here review the properties of anthracite as a fuel, primarily in industrial markets, as well as present use and trends for future use. This report focuses on the anticipated effect of an exemption for anthracite from the industrial boiler sulfur dioxide NSPS, currently under development by the Environmental Protection Agency. At present, on a national basis industrial bolers are not a major market for anthracite. In 1973, only 1.26 percent of the coal burned in major industrial boilers was anthracite. However, the market for anthracite is a highly regional one; more than half of the anthracite consumed in industrial boilers between 1973 and 1978 was in Pennsylvania. The major constraints to future use of anthracite are its cost relative to substitute fuels and feedstocks and its technical limitations which can be overcome in part by purchasing larger, more expensive, boilers. An exemption for anthracite from sulfur removal requirements in the upcoming NSPS for industrial boilers would make the more expensive but cleaner anthracite competitive with bituminous coal. This analysis estimates the 1995 annual anthracite consumption by industrial boilers. The best case estimate is 2.7 million tons; the worst case is 11,000 tons. Socio-economic factors related to the use of anthracite in Northeastern Pennsylvania are considered.

  19. Neogene rhyolites of the northern Jemez volcanic field, New Mexico

    SciTech Connect

    Loeffler, B.M.; Vaniman, D.T.; Baldridge, W.S.; Shafiqullah, M.

    1988-06-10

    Volcanic centers previously mapped as the 20 Ma El Rechuelos Rhyolite in the northern Jemez volcanic field, New Mexico, include three distinct episodes of rhyolitic volcanism. An early (7.5 Ma) extrusive dome of flow-banded biotite rhyolite and an intermediate (5.8 Ma) rhyolite, possibly a volcanic neck, correspond in age to rhyolites of the Keres Group in the southern Jemez volcanic field. Three other extrusive domes of aphyric, pumiceous rhyolite and obsidian comprise a late volcanic episode, dated at 2.0 Ma. We retain the name El Rechuelos Rhyolite only for these late centers. Another center, farther north than the others but previously mapped with the El Rechuelos Rhyolite, is a dacite pumice ring whose age (5.2 Ma), petrography, major- and trace-element chemistry, and Sr initial ratio all suggest it should be included with rocks of the Tschicoma Formation. Nd and Sr isotopic ratios of the Neogene rhyolites of the northern Jemez volcanic field suggest that these rhyolites were not produced by partial melting of either upper or lower crust. Rather, they may have been generated from a mantle-derived mafic magma, such as the nearby Lobato Basalt, by fractional crystallization with concomitant assimilation of small amounts (<6%) of lower crust. If the El Rechuelos is derived from a lower crust magma chamber, as seems likely, then it is not related to the bandelier magma system, even though it is part of a continuum of rhyolite volcanism ranging from 3.6 Ma to 130,000 years ago that includes the Bandelier and precursor rhyolitic units. copyright American Geophysical Union 1988

  20. New interpretation of Clarks Fork field, northern Bighorn basin, Montana

    SciTech Connect

    Johnson, J.S.; Lindsley-Griffin, N.

    1986-08-01

    Clarks Fork field is located at the northern edge of the Bighorn basin (T9S, R22E) in Carbon County, Montana. Production was first established in 1944 by General Petroleum Corporation in the Cretaceous Peay Sandstone (basal Frontier) and was later extended to the Cretaceous Greybull (1949) and Lakota (1956) sandstones by British American. Total cumulative hydrocarbons from this field are 1,1789,193 bbl of oil and 3,061,522 mcf of gas, with Lakota sandstones being most productive. Lakota production occurs from a structural-stratigraphic trap in an east-west-trending channel on the axis of Clarks Fork anticline, geographically near the center of the township. Our structural reinterpretation of Clarks Fork field suggests that Elk Basin anticline is a northwest extension of the Elk Basin field anticline. The Elk Basin thrust truncates the north limb of the fold and does not strike to the northwest, as shown by earlier interpretations. They interpret a northwest-striking thrust in the center of the township as a splay off the Elk Basin thrust, and have named it the Clarks Fork thrust. The Clarks Fork anticline is located on the hanging wall of Clarks Fork thrust. Subsurface maps indicate the Clarks Fork area has not been fully developed. Stratigraphic traps in the Lakota and Greybull sandstones are present in several areas of the township. Structural traps in the center and northwest portions of the township may also exist.

  1. Maximizing the existing potential of new foreign markets for anthracite: Executive summary

    SciTech Connect

    Ziolkowski, L.W.; Ahn, Y.K.; Hong, S.P.

    1988-09-01

    The major purposes of this report were to: (1) conduct an in-depth survey of both the technical and marketing problems in the United States Anthracite Industry (predominately in Northeastern Pennsylvania); and (2) make recommendations in areas of technical R and D needs that will enhance the United States export of anthracite to foreign markets (especially Korea). Furthermore, the report identifies various anthracite culm drying and other coal utilization concepts; recommends several anthracite utilization configurations which appear to be the most suitable to the Korean market and a sensitivity analysis on these configurations; and identifies several solutions to resolve some of the problems which were identified relative to: (a) reducing the price of exporting anthracite; (b) the producers quality control activities which relate to meeting the Korean specifications and generally improving the understanding on the contract terms that relate to the encouragement of long term commitments of anthracite by Korea. 5 figs., 11 tabs.

  2. Influence of gas composition of the modulus of elasticity of gas-impregnated anthracites

    SciTech Connect

    Vinokurova, E.B.; Ketslakh, A.I.

    1986-07-01

    A study of the elastic properties of anthracites under strain and high gas pressure is described. The tests were made on Class I and II anthracites after exposure to helium, nitrogen, methane, carbon dioxide, and a mixture of these gases similar in composition to that of natural gas in worked anthracite strata. Each test sample was loaded in air at atmospheric pressure, and then subjected to vacuum treatment and impregnated with gas. Tables show strain on samples in air at atmospheric pressure in helium, nitrogen, methane and gas mixtures, and values of modulus of elasticity for anthracite in various gases. It was shown that impregnation with carbon dioxide under pressure has a destructive influence on the anthracite. The presence of 1.5% of carbon dioxide in a gas is sufficient to cause a reduction in the modulus of elasticity. During the working of a stratum, the consequential change in the gas content also alters the mechanical properties of the anthracite.

  3. Modified anthracites as selective sorbents for platinum metals

    SciTech Connect

    Tikhonova, L.P.; Lyubchik, S.B.; Tarasenko, Y.A.; Goncharik, V.P.; Galushko, O.L.; Fonseca, I.

    2006-05-15

    Methods of preliminary modification were used to obtain activated carbons with low ash content (0.2%), developed pi-conjugated electronic system, large surface area, and wide pore size distribution, from exclusively microporous carbons to those of mesoporous type. The adsorption of compounds of platinum-group metals on activated anthracite from single-component (as regards the platinum metal: Pd, Pt, or Rh) and multicomponent (Pd, Pt) solutions containing compounds of concomitant metals was studied.

  4. The red oak - white oak forests of the Anthracite Region

    Treesearch

    C. F. Burnham; M. J. Ferree; F. E. Cunningham

    1947-01-01

    The red oak - white oak forests of the Anthracite Region occupy as substantial portion - 28.6 percent or 915,200 acres - of the region's 3,198,400 acres of forest land. These forests have been so heavily cut for lumber and mine timbers during the past 100 years and have been so badly ravaged by fire following these heavy cuttings that in their present condition...

  5. Lime retention in anthracite coal-breaker refuse

    Treesearch

    Miroslaw M. Czapowskyj; Edward A. Sowa

    1973-01-01

    Hydrated lime was applied to extremely acid anthracite coal-breaker refuse at rates of 2.5 and 5.0 tons per acre. The lime raised the pH to neutral range, and this range was still in evidence 7 years after treatment. The pH readings decreased with the depth of the refuse profile, and below 9 inches they approximated those of the control plots. The 2.5-tons-of-lime-per-...

  6. Stress field evolution in the northwest Himalayan syntaxis, northern Pakistan

    NASA Astrophysics Data System (ADS)

    Pêcher, A.; Seeber, L.; Guillot, S.; Jouanne, F.; Kausar, A.; Latif, M.; Majid, A.; MahéO, G.; Mugnier, J. L.; Rolland, Y.; van der Beek, P.; van Melle, J.

    2008-12-01

    We have conducted a systematic inversion of striated fault planes throughout northern Pakistan in order to better depict the temporal and spatial variations in stress patterns. Two domains are evidenced at a regional scale, separated by the active Raikhot fault, the western boundary of the Nanga Parbat spur. West of this fault, a wrench-type stress field with σ1 axis oriented around N-S predominates in the Karakorum and in Kohistan. It predates Pliocene-Quaternary exhumation of Nanga Parbat and corresponds to the Miocene or earlier regional stress field related to Indian-Asian convergence. East of the Raikhot fault, compression parallel to the belt accounts for initiation of the Nanga Parbat anticlinorium after 5 Ma. It is followed by predominant post-2 Ma extension, both parallel to the belt and NNE-SSW oriented. Thus, in the N-W Himalayan syntaxis, multidirectional extension is juxtaposed on short timescales to shortening either parallel or perpendicular to the belt. Such juxtaposition could be characteristic of strain and stress partitioning during oblique convergence.

  7. Ignition temperatures of a high-ash Portuguese anthracite: Comparison with a low-ash Pennsylvania anthracite

    SciTech Connect

    Seixas, J.P.S.; Essenhigh, R.H.

    1986-11-01

    In this note the authors report values of ignition temperatures of a high-ash Portuguese anthracite. In this method, small samples of sieve-sized particles are floated into heated air at a very dilute concentration, and the lowest air temperature (T/sub i,g/) at which the particles will just ignite is determined. The characteristic of the coal used in these experiments that is of particular significance, in this extension of the still-sparse data-base of ignition temperatures, is the very high ash. The proximate and ultimate analyses are given in Table 1. At nearly 50% ash, this far exceeds anything previously reported. However, as they show below, the values obtained for the ignition temperatures are reasonably comparable to those reported elsewhere for a Pennsylvania anthracite.

  8. Effect of Natural Mineral Inclusions on the Graphitizability of a Pennsylavania Anthracite

    SciTech Connect

    Pappano, Peter J

    2009-01-01

    Four Pennsylvania anthracites of varied carbon content and mineral matter levels were selected from active mines and heat-treated to increasing temperatures. Carbides formed at ~2200 C and then decomposed at ~2500 C. This carbide formation and decomposition process aided in the global graphitization mechanism of the anthracites, and was the sole graphitization mechanism for at least one of the anthracite samples. The most highly graphitizing anthracite was demineralized and then heat treated to typical graphitization temperatures. X-ray diffraction (XRD) of the heat treated de-mineralized sample showed that the (112) peak, which is indicate of three dimensional ordering, previously observed in the native heat-treated anthracite were no longer present. The demineralized anthracite was re-mineralized by adding four types of minerals back to the demineralized sample. The re-mineralized sample was then heat treated and was then found to exhibit the (112) in XRD. The absence of the (112) XRD peak after removal of minerals and heat- treatment, followed by re-appearance of the peaks after re-mineralization and heat treatment strongly suggests that the anthracite was only graphitizable if mineral matter was present. Mineral matter associated with anthracite must have some beneficiary role in the global graphitization mechanism, and may explain why some anthracites are more graphitizable than others.

  9. Cooperation and conflict: field experiments in Northern Ireland.

    PubMed

    Silva, Antonio S; Mace, Ruth

    2014-10-07

    The idea that cohesive groups, in which individuals help each other, have a competitive advantage over groups composed of selfish individuals has been widely suggested as an explanation for the evolution of cooperation in humans. Recent theoretical models propose the coevolution of parochial altruism and intergroup conflict, when in-group altruism and out-group hostility contribute to the group's success in these conflicts. However, the few empirical attempts to test this hypothesis do not use natural groups and conflate measures of in-group and unbiased cooperative behaviour. We conducted field experiments based on naturalistic measures of cooperation (school/charity donations and lost letters' returns) with two religious groups with an on-going history of conflict-Catholics and Protestants in Northern Ireland. Conflict was associated with reduced donations to out-group schools and the return of out-group letters, but we found no evidence that it influences in-group cooperation. Rather, socio-economic status was the major determinant of cooperative behaviour. Our study presents a challenge to dominant perspectives on the origins of human cooperation, and has implications for initiatives aiming to promote conflict resolution and social cohesion.

  10. Cooperation and conflict: field experiments in Northern Ireland

    PubMed Central

    Silva, Antonio S.; Mace, Ruth

    2014-01-01

    The idea that cohesive groups, in which individuals help each other, have a competitive advantage over groups composed of selfish individuals has been widely suggested as an explanation for the evolution of cooperation in humans. Recent theoretical models propose the coevolution of parochial altruism and intergroup conflict, when in-group altruism and out-group hostility contribute to the group's success in these conflicts. However, the few empirical attempts to test this hypothesis do not use natural groups and conflate measures of in-group and unbiased cooperative behaviour. We conducted field experiments based on naturalistic measures of cooperation (school/charity donations and lost letters' returns) with two religious groups with an on-going history of conflict—Catholics and Protestants in Northern Ireland. Conflict was associated with reduced donations to out-group schools and the return of out-group letters, but we found no evidence that it influences in-group cooperation. Rather, socio-economic status was the major determinant of cooperative behaviour. Our study presents a challenge to dominant perspectives on the origins of human cooperation, and has implications for initiatives aiming to promote conflict resolution and social cohesion. PMID:25143042

  11. Applicability of the mixture of bituminous coal and anthracite to conventional pulverized coal firing boiler

    SciTech Connect

    Takano, Shin-Ichi; Kiga, Takashi; Miyamae, Shigehiro

    1994-12-31

    In some future, it is expected for Japanese power stations to be hard to get a high-grade coal like a bituminous coal. We conducted therefore pilot scale tests of pulverized blends of bituminous coal and anthracite using a 1.2MWt tunnel furnace in order to evaluate the applicability of the blends of bituminous coal and anthracite to conventional pulverized coal firing boilers. One kind of bituminous coal and two kinds of anthracite, one was of low ash content and another was of high ash content, were prepared for the test. Previously to pilot scale tests, coal properties and ash properties of the blends of bituminous coal and anthracite were analyzed to estimate the characteristics of combustion, ash deposition, and so on. In the test, we investigated the combustion efficiency, NOx emission, characteristics of ignition stability and grindability changing the blend rate of anthracite. Results of our study indicated that the critical restrictions on the blending rate of anthracite were unburnt carbon in fly ash and NOx emission as for coals tested. The acceptable limitation on blending rate of anthracite was 10 and 20%, respectively for two kinds of conventional pulverized coal fired boiler. Concerning to the grindability, it became worse with increasing the blending rate of anthracite from grindability test using a roller mill, while it became better estimating from HGI.

  12. The thermal transformations of pitch and its compositions with thermo-anthracite

    SciTech Connect

    Belkina, T.V.; Ulanovskii, M.L.; Krysin, V.P.

    1983-01-01

    The derivatographic method was used to examine the nature of thermal treatment of pitch in a mixture with heat-treated anthracite. The basic effect of anthracite on the thermal conversion of pitch was established, as well as the stages of mass loss and the processes that limit such losses. (9 refs.)

  13. Influence of the dispersity of anthracite on the rearrangement of its structure during heat treatment

    SciTech Connect

    Fialkov, A.S.; Chuparova, L.D.; Abramov, A.V.; Kirilin, N.S.; Yurkovskii, I.M.; Suslina, V.I.; Semenov, M.V.

    1983-01-01

    An investigation has been carried out on the effect of the degree of dispersion of anthracite on its structural transformation and its adsorption properties with respect to a binder. It was shown that a composition based on highly ordered anthracite can be obtained from a powder having a specific surface area in the range 14-20 m/sup 2//g. (9 refs.)

  14. 30 CFR 785.11 - Anthracite surface coal mining and reclamation operations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Anthracite surface coal mining and reclamation..., DEPARTMENT OF THE INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL EXPLORATION... Anthracite surface coal mining and reclamation operations. (a) This section applies to any person...

  15. 30 CFR 785.11 - Anthracite surface coal mining and reclamation operations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Anthracite surface coal mining and reclamation..., DEPARTMENT OF THE INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL EXPLORATION... Anthracite surface coal mining and reclamation operations. (a) This section applies to any person...

  16. 30 CFR 785.11 - Anthracite surface coal mining and reclamation operations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Anthracite surface coal mining and reclamation..., DEPARTMENT OF THE INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL EXPLORATION... Anthracite surface coal mining and reclamation operations. (a) This section applies to any person...

  17. Computer simulation of nonstationary thermal fields in design and operation of northern oil and gas fields

    SciTech Connect

    Vaganova, N. A.; Filimonov, M. Yu.

    2015-11-30

    A mathematical model, numerical algorithm and program code for simulation and long-term forecasting of changes in permafrost as a result of operation of a multiple well pad of northern oil and gas field are presented. In the model the most significant climatic and physical factors are taken into account such as solar radiation, determined by specific geographical location, heterogeneous structure of frozen soil, thermal stabilization of soil, possible insulation of the objects, seasonal fluctuations in air temperature, and freezing and thawing of the upper soil layer. Results of computing are presented.

  18. Change in the composition of anthracite on storage and in the tissues of the organism

    SciTech Connect

    Kukharenko, T.A.; Lutsenko, L.A.; Mel'nikova, S.A.

    1982-01-01

    Prolonged storage in the open air oxidizes anthracite and appreciably reduces its carbon content. Peaks appear in the infra-red spectrum typical of oxygen-containing groups. A slight reduction in the H/C ratio, despite a high-level general background being maintained, suggests that there are no changes in the basic molecular structure. In contact with the human organism, on the other hand, anthracite dust undergoes marked changes in its organic substance and a reduction in the ash yield. There is reason to suppose that, in contrast to bituminous coal, the oxidative hydrolytic decomposition of anthracite in the organism is accompanied by reaction or sorption of tissue protein. The spectrogram of an anthracite sample shows absorption peaks in the infra-red region which are typical of aromatic, aliphatic and alicyclic structures and indicate that this anthracite falls in the 'higher reduced' category. (8 refs.)

  19. Evaluation of anthracite as a coal-water slurry fuel. Final report

    SciTech Connect

    Not Available

    1985-02-01

    This study evaluated the use of anthracite as a coal-water slurry fuel. The study consisted of two major activities: (1) fundamental slurry formulation experiments leading to the production and combustion characteristics investigation of suitable, anthracite slurries, and (2) analytical evaluations of the potential of anthracite slurry as a boiler fuel for new industrial and utility boiler application and for retrofit application of an industrial oil-fired boiler. The study results have shown that anthracite can be readily processed into a coal-water slurry with coal loading 70 wt % coal and 30% water plus chemical additives. Slurry viscosity, handling, and storage characteristics are similar to the bituminous coal-water slurries that are under active commercial development. Commercial anthracite-water slurry processing cost is projected to be only slightly higher than for bituminous coal-water slurry. Combustion testing in a small, industrial, water-tube boiler has shown that stable combustion of anthracite-water slurry can be achieved with high carbon conversion. The results also indicate that oxygen enrichment and secondary fuel firing can compensate for the low volatile content of the anthracite to achieve good combustion. Under the conditions assumed, anthracite-water slurry was not an economical fuel retrofit option for an existing oil-fired, industrial boiler. Contributing significantly to the economic results were the requirement for secondary fuel and oxygen to achieve good anthracite slurry combustion in the oil-designed boiler. Minimizing or eliminating the secondary fuel and oxygen requirements through a continued burner/boiler development program or more radical boiler modification to fire low-volatile fuel would greatly improve conversion economics and likely make anthracite-water slurry a candidate for industrial boiler fuel retrofit. 10 refs., 22 figs., 38 tabs.

  20. Experimental Study of High-Temperature Fracture Propagation in Anthracite and Destruction of Mudstone from Coalfield Using High-Resolution Microfocus X-ray Computed Tomography

    NASA Astrophysics Data System (ADS)

    Xiao, Yang; Lu, Jun-Hui; Wang, Cai-Ping; Deng, Jun

    2016-09-01

    The coalfield fire is determined by fractures of coal and rock that provide tunnel for gases and heat exchange. To study fracture propagation at high temperatures, high-resolution X-ray computed tomography (CT) was used to scan anthracite and mudstone samples collected from the Qinshui coalfield, Shanxi Province, northern China. The samples were scanned at 100 °C intervals as they were subjected to temperatures of up to 500 °C. Three-dimensional images were reconstructed by the CT software to analyze changes in the fractures and pores in the samples. The experimental results show that fracturing of anthracite began at 200 °C. The generation rate of fractures in the coal samples increases slowly below 300 °C, but above 300 °C there is a sharp increase in fracture development. This indicates that the thermal fracturing temperature threshold for anthracite is 300 °C. During the experiment, it was found that preexisting fractures, voids, and regenerative fractures formed around the hard portions of anthracite particles or along the weak boundaries between particles. Some regenerative fractures developed along the fabric of the relatively crystalline particles within the particle and terminate at the edge of the particle or where the fracture encounters a harder portion of coal. Some fractures even expanded enough to be transformed into voids as temperatures rose. In the mudstone, the porosity changed suddenly at 300 °C. This indicated that there was a void generated at 200 °C, but the void expanded when the temperature was increased. However, changes in the void were not obvious from 200 to 300 °C.

  1. Co-Combustion of Refuse Derived Fuel with Anthracites in a CFB Boiler

    NASA Astrophysics Data System (ADS)

    Kim, Dong-Won; Lee, Jong-Min; Kim, Jae-Sung

    Combustion of Refuse derived fuel (RDF) is considered as a priority solution to energy recovery from municipal solid waste (MSW). The co-combustion characteristics of anthracite coals with RDF were determined in the commercial scale Tonghae CFB Power Plant. As the feeding ratio of the RDF to the anthracites increased to 5%, temperature and pressure were not changed in comparison with firing only anthracites. The amount of the required air was reduced due to high O2 content in RDF relative to the anthracites. The emissions of NOx, SOx, HCl and Dioxin were also measured. According to higher mixing ratio of the RDF to the anthracites, SOx, NOx emissions slightly decreased and HCl emissions increased, because RDF has relatively smaller S, N and higher CI than the anthracites. Heavy metals of the fly ash and bottom ash and the dioxin emissions were far below Korean maximum permissible concentration level at incinerator. The results showed that it is of great use and technically possible to co-combustion of RDF with the anthracites by 5% in the form of fuel recovery and energy production in commercial scale CFB boiler.

  2. Combustion characteristics of blended coal of bituminous and anthracite

    SciTech Connect

    Shon, E.K.; Choi, S.I.; Lee, S.H.; Hyun, J.S.; Park, C.S.

    1997-12-31

    Blending coals as a means of meeting air emission standards and controlling coal quality is receiving increased attention as both the demand for and the cost of suitable fuels increases. In some countries, the objectives of blending coals are to reduce SO{sub 2} emission, to decrease slagging and fouling problems, to control coal quality, and to reduce the cost of fuels. Comprehensive research on ignition, burnout and slagging characteristics of 2 kinds of Korean anthracite coal (Dongwon, Jangsung) and 1 imported bituminous coal (Ulan) and their blended coals with different blended ratios have been performed with thermogravimetry analysis technique, a drop-tube furnace and a P/C test furnace. The optimum blended ratios have been determined by means of a case by case experiment of 10%, 20% and 30% blending ratio, which provides an engineering basis for the design and operation of power station using the blended coal.

  3. 30 CFR 800.70 - Bonding for anthracite operations in Pennsylvania.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., DEPARTMENT OF THE INTERIOR BONDING AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER... this subchapter shall apply to bonding and insuring anthracite surface coal mining and...

  4. 30 CFR 800.70 - Bonding for anthracite operations in Pennsylvania.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., DEPARTMENT OF THE INTERIOR BONDING AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER... this subchapter shall apply to bonding and insuring anthracite surface coal mining and...

  5. 30 CFR 800.70 - Bonding for anthracite operations in Pennsylvania.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., DEPARTMENT OF THE INTERIOR BONDING AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER... this subchapter shall apply to bonding and insuring anthracite surface coal mining and...

  6. Growth, cull, and, mortality as factors in managing timber in the Anthracite Region

    Treesearch

    Miles J. Ferree

    1948-01-01

    Timberland owners in the Anthracite Region of Pennsylvania frequently ask: What tree species grow best in the region? How large should they be grown? How should we treat them to get the most out of them?

  7. Influence of the dispersity of anthracite on the rearrangement of its structure during heat treatment

    SciTech Connect

    Fialkov, A.S.; Abramov, A.V.; Chuparova, L.D.; Kirilin, N.S.; Semenov, M.V.; Suslina, V.I.; Yurkovskii, I.M.

    1983-01-01

    The influence of the dispersity of anthracite on the rearrangement of its structure and its absorption capacity with respect to a binder has been investigated. It has been shown that a composition based on anthracite with a high degree of ordering of the structure can be obtained if the specific surface of the powder is not less than 14 m/sup 2//g but not more than 20 m/sup 2//g.

  8. Burning anthracite at B and W downshot unit and burner upgrading

    SciTech Connect

    Zhou, J.

    1998-12-31

    Low volatile matter (VM) coals have difficulty on ignition, flame stability and burnout. A conventional utility boiler can`t successfully utilize such coals. The applications of enhancing ignition steps, proper burner type and its arrangement plus staging combustion as well as a suitable furnace configuration, along or in combination, may burn such low VM coals with high efficiency. B&W downshot units in Shang An Power Plant (S-Plant) in China applies a downshot firing with a W-shape flame plus primary air exchange burner (PAX) and staging combustion in a combination which achieved a great success in burning the design coal. The design coal is a blended coal (25% Yangquan (YQ) anthracite and 75% Shuyang lean) resulting a 13.95% VMdmf ranking as a semi-anthracite per ASTM-D338. In 1995, all 20 burner registers of Unit 1 had been upgraded. S-Plant and B and W decided to conduct a high anthracite blending coal (75% anthracite) combustion tests. The unit had demonstrated a great fuel flexibility. Based on the achievements, the all burner and staging ports of Unit 2 has been upgraded in 1997. In order to further demonstrate the great enhancing ignition feature, B and W had entrusted Chinese TPRI to conduct 100% YQ anthracite burn tests in May 1998. These tests reveal that with 100% anthracite firing, the ignition was fast and on time; the flame and combustion were very stable. Three days (58 continuous hours) 100% anthracite firing was carried out with the load range from the full (350 MW) to half (170--175 MW). The minimum load of 170--175 MW (48--50% MCR) without oil support was easy to maintain. Due to the plant policy, they don`t allow further reduction of the minimum load lower than 50% MCR. These tests have greatly demonstrated the capability of these units burning 100% anthracite.

  9. Gasification reactivity and kinetics of typical Chinese anthracite chars with steam and CO{sub 2}

    SciTech Connect

    Linxian Zhang; Jiejie Huang; Yitian Fang; Yang Wang

    2006-05-15

    The gasification reactivities of six typical Chinese anthracite chars with steam and CO{sub 2} at 0.02-0.1 MPa and 920-1050{sup o}C were investigated by using thermogravimetric analysis (TGA). The reactivities of anthracite chars during steam gasification were found to have a good correlation to the coal volatile matter contents. The higher the coal volatile matter content, the higher the reactivity. The difference in reactivities of anthracite chars during CO{sub 2} gasification seems to be more dependent on the catalytic effect of inherent minerals in anthracite. The results show that the greater the alkali index, the higher the reactivity. The reactivities of demineralized anthracite chars vary very little compared with those the undemineralized chars at higher temperatures, whereas the reactivities of demineralized chars from Jincheng and Rujigou are lower than those of undemineralized ones and the reactivities of demineralized chars from Yangquan, Hunan, Guangdong, and Longyan are higher than those of undemineralized chars at lower temperatures. The homogeneous model and shrinking core model were examined as ways to interpret the experimental data. The experimental results could be well-described by the shrinking core model for anthracite chars during steam and CO{sub 2} gasification. Comparison of the reactivities for anthracite chars during steam and CO{sub 2} gasification shows that the reactivities of anthracite chars during steam gasification are far higher than those during CO{sub 2} gasification. The reactivities of the former are about 10 times higher than those of the latter, and this ratio is far greater than that of the lignite and bituminous coal. The mechanism leading to this difference is discussed. 33 refs., 15 figs., 8 tabs.

  10. Effect of natural mineral inclusions on the graphitizability of a Pennsylvania anthracite

    SciTech Connect

    Peter J. Pappano; Harold H. Schobert

    2009-01-15

    A Pennsylvania anthracite was heat-treated to temperatures in excess of 2000{sup o}C. Carbides formed at 2200{sup o}C and then decomposed at 2500{sup o}C. This process aided in the graphitization of the anthracite. The carbide formation-decomposition reactions were the sole graphitization mechanism for this anthracite. This was shown by demineralizing (to remove the natural mineral inclusions) and then heat-treating the sample to 2600{sup o}C. X-ray diffraction (XRD) of the heat-treated demineralized sample showed that the (112) peak, which is indicative of three-dimensional ordering and was previously observed in the native heat-treated anthracite, was no longer present. The demineralized anthracite was remineralized by individually adding four types of minerals (rutile, quartz, calcite, and hematite) to demineralized samples. Each of the remineralized samples was heat-treated and found to exhibit the (112) peak again. The absence of the (112) XRD peak after removal of minerals and heat treatment followed by its reappearance after remineralization and heat treatment strongly suggests that the anthracite was only graphitizable if mineral matter was present. 37 refs., 10 figs., 2 tabs.

  11. Manifestation of Strong Coupling Between Microwave Photons and Spins in the epr Spectrum of Anthracite

    NASA Astrophysics Data System (ADS)

    Fedaruk, R.; Adashkevich, S. V.

    2014-07-01

    The change of the anthracite EPR signal shape that was caused by increasing the sample size was observed by continuous-wave EPR with automatic frequency control locked to the measuring cavity. For large samples (>10 mm3), hysteresis (a difference in the resonant magnetic flux densities when the magnetic field was scanned upwards or downwards) and a bistability (a sharp amplitude change) were observed. A two-peak spectrum for a strongly coupled system formed by an electron-spin ensemble and the cavity microwave field was found by changing the frequency of the microwave oscillator during recording of the EPR signals. The difference in the frequencies of these peaks (Rabi splitting) was a measure of the coupling strength between the spins and the microwave field and increased with increasing sample size. The simultaneous increase of the hysteresis and bistability of the EPR signals provided evidence that these peculiarities were caused by the Rabi splitting. Use of the Rabi splitting to determine the number of electron spins in a sample was proposed.

  12. Combustion characteristics and kinetics of anthracite with added chlorine

    NASA Astrophysics Data System (ADS)

    Wang, Cui; Zhang, Jian-liang; Wang, Guang-wei; Jiao, Ke-xin; Liu, Zheng-jian; Chou, Kuo-chih

    2017-07-01

    The combustion process of Yangquan anthracite (YQ) with the addition of 0.045wt%, 0.211wt%, 1.026wt%, and 2.982wt% chlorine was investigated using a thermogravimetric method from an ambient temperature to 1173 K in an air atmosphere. Results show that the YQ combustion characteristics are not significantly affected by an increase in chlorine content. Data acquired for combustion conversion are then further processed for kinetic analysis. Average apparent activation energies determined using the model-free method (specifically the KAS method) are 103.025, 110.250, 99.906, and 110.641 kJ/mol, respectively, and the optimal kinetic model for describing the combustion process of chlorine-containing YQ is the nucleation kinetic model, as determined by the z( α) master plot method. The mechanism function of the nucleation kinetic model is then employed to estimate the pre-exponential factor, by making use of the compensation effect. The kinetic models to describe chlorine-containing YQ combustion are thus obtained through advanced determination of the optimal mechanism function, average apparent activation energy, and the pre-exponential factor.

  13. Water quality of large discharges from mines in the anthracite region of eastern Pennsylvania

    USGS Publications Warehouse

    Wood, C.R.

    1996-01-01

    In 1991, 99 of the 102 coal mines in the anthracite coal fields of Pennsylvania that discharged 1.0 cubic foot per second or more when water-quality samples were collected in 1975 were revisited. Water was not discharging from 15 of these 99 mines in 1991. Discharge, water temperature, specific conductance, pH, dissolved oxygen, sulfate, iron, manganese, alkalinity, and acidity were measured in water samples collected at 84 mines to assess changes in water quality from 1975 to 1991. The pH increased in water samples of 64 of the 81 mines. However, acidity was essentially unchanged. Concentrations of iron decreased in water discharge samples from 57 of 82 mines, manganese concentrations decreased in samples from 23 of 26 mines, and sulfate concentrations decreased in samples from 62 of 77 mines. The median change in sulfate was a decrease of 139 milligrams per liter. Alkalinity increased in water discharge samples from 43 mines, remained the same at 22 mines, and decreased at 14 mines. In 1975, the samples were collected during high base flow in the spring; in 1991, samples were collected during lower-than-normal base flow in the fall. This may have affected the comparison. Many mine discharges have elevated concentrations of aluminum, calcium, cobalt, iron, lithium, magnesium, manganese, nickel, strontium, zinc, and sulfate.

  14. A review of the use of anthracite in electric arc furnace steelmaking

    SciTech Connect

    Rozelle, P.L.

    1994-12-31

    The applications of anthracite in Electric Arc Furnace (EAF) steelmaking, include the adjustment of hot metal carbon content, the generation of foamy slags, and its use as a support fuel in the EAF to reduce power consumption per tonne of product. Incentives to use support fuel in EAF steelmaking include the reduction of electric power consumption without reducing plant output. As such, the concept can reduce steelmaking costs and can serve as a basis for maximizing an EAF operation`s demand side management program. The use of carbon and oxygen additions to the EAF can cause significant release of energy within the furnace. This energy can offset a portion of the electrical energy required by the system for production of steel. Reduced consumption of electricity per tonne of hot metal is the result Electrode consumption and tap to tap times can also be reduced. significant interest in the use of anthracite as EAF support fuel, as well as the other applications of anthracite in EAF steelmaking, have combined to establish the EAF steelmaking trade as a significant market sector for anthracite. This discussion is a review of key anthracite properties and production considerations, and their interplay with the requirements of the EAF process.

  15. GPS constraints on velocity field and uplift of the Northern Caucasus

    NASA Astrophysics Data System (ADS)

    Milyukov, V.; Kopaev, A.; Zharov, V.; Kaufman, M.; Mironov, A.; Myasnikov, A.; Chen, T.

    2009-04-01

    The northern part of the Greater Caucasus is one of the most geodynamically active regions of Russia. From the standpoint of modern geodynamics, the features of this region are a typical example of collision tectonics resulting from interaction between Scythian plate and Alpine-Himalaya tectonic belt. The GPS observations in the Northern Caucasus area began in 1993 as a part of the WEGENER project. One of the points of the GPS measurements was transformed in the stationary station, side code ZECK in EUREF. Within the last few years we have established three new stationary GPS/GLONASS stations in the Northern Caucasus (site codes TRSK, KISL and VLAD). Currently, four stationary GPS/ GLONASS stations located in this area form the base of the regional Northern Caucasus Deformation Array (NCDA). Based on the results of first observations we find constraints on the velocity field and uplift of the Northern Caucasus. The striking aspect of the velocity field of the Northern Caucasus is the rapid motion in the north-east direction with almost equal velocities of about 28 mm/yr. The motion of the feducial site MDVJ (Moscow region) is characterized by a similar velocity value (~25 mm/yr) in the same direction. This means that the motion of the Northern Caucasus region is mainly defined by the general tectonic movement of the Eurasian plate with respect to ITRF. With respect to the uplift of the Northern Caucasus region, the situation is ambiguous. The uplift of the ZECK site derived from the GPS data coincides with an estimation obtained on the basis of absolute gravity measurements over a thirteen-years period (2 mm/yr). Apparently this is a real uplift value. The greatest uplift (8.8 mm/yr) is observed for station TRSK. This station is situated near to the volcano Elbrus (3 km from the top). The local effect connected with inflation of magmatic chambers of the Elbrus volcano may be one of the possible explanations of the uplift value of the TRSK site. A similar uplift (8

  16. Effects of Varying Particle Sizes and Different Types of LDH-Modified Anthracite in Simulated Test Columns for Phosphorous Removal.

    PubMed

    Zhang, Xiangling; Chen, Qiaozhen; Guo, Lu; Huang, Hualing; Ruan, Chongying

    2015-06-16

    A comparative study was carried out for the removal of phosphorus in simulated unplanted vertical-flow constructed wetlands with different layered double hydroxide (LDHs) coated anthracite substrates. Three particle sizes of anthracites were selected and modified separately with nine kinds of LDH coating. The simulated substrates test columns loaded with the original and modified anthracites were constructed to treat the contaminated water. For the medium and large particle size modified anthracite substrates, the purification effects of total phosphorus, total dissolved phosphorus and phosphate were improved by various degrees, and the purification effect of the medium particle size anthracite is better than that of the large size one. The medium size anthracite modified by ZnCo-LDHs had optimal performance with average removal efficiencies of total phosphorus, total dissolved phosphorus and phosphate reaching 95%, 95% and 98%, respectively. The maximum adsorption capacity on ZnCo-LDHs and ZnAl-LDHs modified medium sizes anthracites were 65.79 (mg/kg) and 48.78 (mg/kg), respectively. In comparison, the small size anthracite is not suitable for LDHs modification.

  17. Effects of Varying Particle Sizes and Different Types of LDH-Modified Anthracite in Simulated Test Columns for Phosphorous Removal

    PubMed Central

    Zhang, Xiangling; Chen, Qiaozhen; Guo, Lu; Huang, Hualing; Ruan, Chongying

    2015-01-01

    A comparative study was carried out for the removal of phosphorus in simulated unplanted vertical-flow constructed wetlands with different layered double hydroxide (LDHs) coated anthracite substrates. Three particle sizes of anthracites were selected and modified separately with nine kinds of LDH coating. The simulated substrates test columns loaded with the original and modified anthracites were constructed to treat the contaminated water. For the medium and large particle size modified anthracite substrates, the purification effects of total phosphorus, total dissolved phosphorus and phosphate were improved by various degrees, and the purification effect of the medium particle size anthracite is better than that of the large size one. The medium size anthracite modified by ZnCo-LDHs had optimal performance with average removal efficiencies of total phosphorus, total dissolved phosphorus and phosphate reaching 95%, 95% and 98%, respectively. The maximum adsorption capacity on ZnCo-LDHs and ZnAl-LDHs modified medium sizes anthracites were 65.79 (mg/kg) and 48.78 (mg/kg), respectively. In comparison, the small size anthracite is not suitable for LDHs modification. PMID:26086702

  18. CFB evaluation of high-ash Ukrainian anthracite coal

    SciTech Connect

    Perna, M.A.; Fuller, T.A.; Reuther, J.; Belin, F.; Maryamchik, M.; Maystrenko, A.

    1996-12-31

    High-ash Ukrainian anthracite coal (called schtib) was evaluated to determine its impact on design for commercial-scale circulating fluidized bed (CFB) boilers. The project was performed to support the US/Ukraine Clean Coal Task Force efforts to upgrade Ukraine`s coal-fired power plants. The project was sponsored by the US Agency for International Development (USAID) through the US Department of Energy, Pittsburgh Energy Technology Center (DOE-PETC). The test work was performed at the Institute of Energy Savings Problems (IESP) in Kiev, Ukraine and at the Babcock and Wilcox (B and W) Research Center in Alliance, Ohio. Parametric tests were performed on small-scale and pilot-scale CFB facilities to examine the effects of operating parameters and fuel particle size distribution on combustion and emissions performance. Test results indicate that with fuel crushed to minus 1/8 inches and an average operating temperature of 1,650 F, stable combustion without support fuel and low unburned carbon loss (<3%) can be achieved within a 50--100% load range. Gaseous emissions of sulfur dioxide were successfully controlled to about 90% sulfur removal by adding sorbent at a Ca/S ratio of about 1.9. Nitrogen oxide and carbon monoxide emissions were maintained below 0.24 lbs/MBtu and 0.18 lbs/MBtu, respectively during the tests. The test results indicated that B and W`s CFB boilers can be used to fire schtib in an efficient and environmentally acceptable manner and provided input for the refinement of the CFB design for this fuel CFB boilers of 60 Mwe and 200 Mwe capacity for repowering of Ukrainian power plants are being jointly developed by B and W and Ukrainian organizations.

  19. Thermogravimetric investigation on co-combustion characteristics of tobacco residue and high-ash anthracite coal.

    PubMed

    Li, X G; Lv, Y; Ma, B G; Jian, S W; Tan, H B

    2011-10-01

    The thermal behavior of high-ash anthracite coal, tobacco residue and their blends during combustion processes was investigated by means of thermogravimetric analysis (20 K min(-1), ranging from ambient temperature to 1273 K). Effects of the mixed proportion between coal and tobacco residue on the combustion process, ignition and burnout characteristics were also studied. The results indicated that the combustion of tobacco residue was controlled by the emission of volatile matter; the regions were more complex for tobacco residue (four peaks) than for coal (two peaks). Also, the blends had integrative thermal profiles that reflected both tobacco residue and coal. The incorporation of tobacco residue could improve the combustion characteristics of high-ash anthracite coal, especially the ignition and burnout characteristics comparing with the separate burning of tobacco residue and coal. It was feasible to use the co-combustion of tobacco residue and high-ash anthracite coal as fuel. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Optimization of anthracite calcination process in a vertical electric arc furnace

    SciTech Connect

    Perron, J.; Bouvette, J.F.; Dupuis, M.

    1996-10-01

    Anthracite is used for cathode block manufacturing must be calcined prior to its use to eliminate volatile matter and reduce its electrical resistivity. Anthracite calcination in vertical electric arc furnaces is widely used in the industry. It is well known that this technology leads to a radial temperature gradient in the furnace which results in non-homogeneous calcined anthracite properties. Also, operation experience has shown that production of calcination furnaces can be difficult to stabilize if process changes occur, which may lead to variable quality of the calcined material. To optimize the calcination process, an improved control strategy and a mathematical model of Elkem-type electric arc furnace were developed. Using these, it was successfully demonstrated that temperature gradient in the furnace can be reduced and that furnace productivity can be substantially increased.

  1. Combustion-Supporting Effect of Common Carbonous Solid Waste on Anthracites

    NASA Astrophysics Data System (ADS)

    Zhang, Jianliang; Ren, Shan; Liu, Zhengjian; Zhou, Yun; Meng, Fanyi; Su, Buxin

    2012-08-01

    In order to study the combustion characteristics of anthracite with additives, the influence of common carbonous solid waste (CSW) on anthracite is studied by thermogravimetry. The results show that appropriate CSW additives mixed with pulverized coal (PC) at PZH Steel can promote the combustion of PC and increase the burning ratio of anthracite greatly. The greater the additive content, the higher the burning ratio at the same conditions. The dynamics models show that the particle size of CSW additives, oxygen concentration, and the diffusion coefficient of oxygen are all very influential for their combustion characteristics. The heat of CSW combustion is absorbed by coal powder, and it consists of part of the coal powder accumulated heat. Then, accumulated heat is higher than dissipation heat ahead of time, so CSW can support combustion of coal powder effectively.

  2. High Yield Synthesis of Aspect Ratio Controlled Graphenic Materials from Anthracite Coal in Supercritical Fluids.

    PubMed

    Sasikala, Suchithra Padmajan; Henry, Lucile; Yesilbag Tonga, Gulen; Huang, Kai; Das, Riddha; Giroire, Baptiste; Marre, Samuel; Rotello, Vincent M; Penicaud, Alain; Poulin, Philippe; Aymonier, Cyril

    2016-05-24

    This paper rationalizes the green and scalable synthesis of graphenic materials of different aspect ratios using anthracite coal as a single source material under different supercritical environments. Single layer, monodisperse graphene oxide quantum dots (GQDs) are obtained at high yield (55 wt %) from anthracite coal in supercritical water. The obtained GQDs are ∼3 nm in lateral size and display a high fluorescence quantum yield of 28%. They show high cell viability and are readily used for imaging cancer cells. In an analogous experiment, high aspect ratio graphenic materials with ribbon-like morphology (GRs) are synthesized from the same source material in supercritical ethanol at a yield of 6.4 wt %. A thin film of GRs with 68% transparency shows a surface resistance of 9.3 kΩ/sq. This is apparently the demonstration of anthracite coal as a source for electrically conductive graphenic materials.

  3. Combustion of anthracite-bituminous coal blends in a spreader stoker boiler at Holston Army Ammunition Plant. Final report

    SciTech Connect

    Harmon, J.A.; Davidson, J.E.; Hartsock, D.K.

    1988-11-01

    A test program was conducted at the Holston Army Ammunition Plant near Kingsport, TN to evaluate the combustion of an anthracite-bituminous coal blend in a spreader stoker boiler designed for bituminous coal only. The test program was structured to evaluate different percentages of anthracite and bituminous in the blend at different operating loads on the boiler. Blends of 15, 22, 30, and 42% anthracite were combusted at loads of 62.5, 50, and 37.5% of the maximum continuous rating (MCR) boiler capacity. Stack testing and ash sampling were performed to monitor combustion performance, in addition to visually inspecting the ash bed. The testing disclosed no technical reasons why anthracite-bituminous blending could not be performed on a long-term basis to meet targeted Army anthracite consumption tonnages.

  4. Reconnaissance of mine drainage in the coal fields of eastern Pennsylvania

    USGS Publications Warehouse

    Growitz, D.J.; Reed, L.A.; Beard, M.M.

    1985-01-01

    Anthracite has been extensively mined in four areas of eastern Pennsylvania. Almost all underground mining in the four areas, the Northern, Eastern Middle, Western Middle, and Southern Fields, has been discontinued and many mines are abandoned and flooded. Precipitation on much of the 408 square miles of coal fields infiltrates to the underground mine complexes, and is discharged as mine drainage from tunnels, mine entrances, and boreholes. Mine drainage was measured and sampled at 251 sites that had a total discharge of 918 cubic feet per second, a total sulfate load of 1,470 tons per day, and a total iron discharge of 79 tons per day. The largest sulfate yield was 5.4 tons per day per square mile from the Western Middle Field. The yields from the Northern, Eastern Middle, and Southern Fields were 4.6, 3.6, and 1.4 tons per day per square mile, respectively.

  5. Field examination of shale and argillite in northern Nye County, Nevada

    SciTech Connect

    Connolly, J. R.; Woodward, L. A.; Emanuel, K. M.; Keil, K.

    1981-12-01

    Thirty-two locales underlain by clay-rich strata ranging from Cambrian Pioche Shale to Mississippian Chainman Shale and equivalents were examined in northern Nye County, Nevada. The text of the report summarizes data for each stratigraphic unit examined. Checklists for tabulating field data at each locale are included in an appendix. Working guidelines used to evaluate the locales include a minimum thickness of 150 m (500 ft) of relatively pure clay-rich bedrock, subsurface depth between 150 m (500 ft) and 900 m (3000 ft), low topographic relief, low seismic and tectonic activity, and avoidance of areas with mineral resource production or potential. Field studies indicate that only the Chainman Shale, specifically in the central and northern parts of the Pancake Range, appears to contain sites that meet these guidelines.

  6. Near-field radioactive particle dynamics and empirical fallout patterns in Chernobyl's Western and Northern Plumes

    NASA Astrophysics Data System (ADS)

    Chesser, Ronald K.; Rodgers, Brenda E.

    We compared geographically referenced ground-based measurements of gamma and beta radiation to model predictions of particle dispersion and estimate the influences of particle sizes, wind speeds, and vertical and lateral turbulence on the near-field (<12 km) fallout patterns resulting from Chernobyl's first two releases of radioactive materials. Excellent conformity between empirical measures and model predictions was found when reasonable atmospheric parameters were assigned. Whereas particle size contributions to the two plumes were similar, atmospheric influences on particle flow differed markedly, resulting in rapid widening, meander, and diminished radiation doses in the Northern Plume relative to that for the narrower and intensely radioactive Western Plume. The Northern Plume is probably the result of multiple particle characteristics released simultaneously. Near-field depositions were due to particulate nuclear fuel probably ejected during helicopter drops of sand onto the burning reactor. Depositions much farther north of the reactor complex were likely due to smaller (1-3 μm) aerosols of volatile radionuclides. Predominant particle sizes in the near-field traces of both plumes were >40 μm in diameter. These large particulates eliminate passive dispersion of oxidized nuclear fuel and aerosol releases of volatile elements as the primary sources of contamination in the Northern Plume at distances <12 km from the Chernobyl reactor.

  7. Chemical oxidation of anthracite with hydrogen peroxide via the Fenton reaction

    USGS Publications Warehouse

    Heard, I.; Senftle, F.E.

    1984-01-01

    Solutions of 30% H2O2 ranging from pH = 0 to pH = 11.5 have been used to oxidize anthracite at room temperature. The inorganic impurities, primarily pyrite, catalysed the oxidation and reduction of H2O2 (the Fenton reaction) to form the hydroxyl radical; the oxidation of the organic matter was minimal and was observed only in strong acidic solutions (pH < 1.5). After acid demineralization, samples of the same anthracite underwent a significant enhancement of oxidation in both acid and alkaline solutions (pH = 0.4-11.5). As all the iron had been removed from the surface and the reactions were completed in a much shorter time, the oxidation mechanism must have been of a different nature than that for the untreated anthracite. A qualitative model based on the catalytic decomposition of H2O2 by activated carbon sites in the coal surface is used to explain the oxidation of the demineralized anthracite. ?? 1984.

  8. 30 CFR 785.11 - Anthracite surface coal mining and reclamation operations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Anthracite surface coal mining and reclamation operations. 785.11 Section 785.11 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL...

  9. 30 CFR 785.11 - Anthracite surface coal mining and reclamation operations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Anthracite surface coal mining and reclamation operations. 785.11 Section 785.11 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL...

  10. Hybrid poplar on two anthracite coal-mine spoils: 10-year results

    Treesearch

    Miroslaw M. Czapowskyj

    1978-01-01

    Unrooted dormant cuttings of 28 hybrid poplar clones were planted on two graded anthracite coal-mine spoils derived from sandstone or from glacial till. Ten-year results show that the plantation survived very well (82 percent), but that growth was extremely varied. Spoil Characteristics and performance of individual clones are presented.

  11. Co-carbonization of two anthracites with a fat coal or two pitches

    SciTech Connect

    Shen, J.; Wang, Z.Z.

    2006-04-15

    The blends of two anthracite powders (YQ and JC) with a fat coal (C4) or a petroleum pitch (PP) or a coal tar pitch (CTP) in different proportions were co-carbonized at 3{sup o}C/min up to 1000{sup o}C in an experimental 1 kg coke oven. Coke yield, coke particulate size, coke micro-strength and coke cracking strength were measured respectively. Coke optical textures were watched under a microscope. The results show that as anthracite proportion increases, coke yields of all blends improve; > 0.8 mm lump coke yields of blends with CTP or PP decline slightly, blends with C4 drop heavily; coke microstrengths do not change sharply, and coke cracking strength of blends with C4 or PP decrease more than blends with CTP. C4 produces fine-grained mosaics, and two anthracites are mainly fusinite and fragments, PP is coarse-grained mosaics, and CTP is chiefly flow or domain textures. Independent optical textures were observed in cokes. There exist evident borders between the two contact optical textures which were produced by different components, and a few phenomena that domain or flow textures penetrating into fusinite appeared in the blends. It seems that CTP is the best adhesives for blending with anthracites for producing high quality cokes.

  12. Binding waste anthracite fines with Si-containing materials as an alternative fuel for foundry cupola furnaces.

    PubMed

    Huang, He; Fox, John T; Cannon, Fred S; Komarneni, Sridhar; Kulik, Joseph; Furness, Jim

    2011-04-01

    An alternative fuel to replace foundry coke in cupolas was developed from waste anthracite fines. Waste anthracite fines were briquetted with Si-containing materials and treated in carbothermal (combination of heat and carbon) conditions that simulated the cupola preheat zone to form silicon carbide nanowires (SCNWs). SCNWs can provide hot crushing strengths, which are important in cupola operations. Lab-scale experiments confirmed that the redox level of the Si-source significantly affected the formation of SiC. With zerovalent silicon, SCNWs were formed within the anthracite pellets. Although amorphous Si (+4) plus anthracite formed SiC, these conditions did not transform the SiC into nanowires. Moreover, under the test conditions, SiC was not formed between crystallized Si (+4) and anthracite. In a full-scale demonstration, bricks made from anthracite fines and zerovalent silicon successfully replaced a part of the foundry coke in a full-scale cupola. In addition to saving in fuel cost, replacing coke by waste anthracite fines can reduce energy consumption and CO2 and other pollution associated with conventional coking.

  13. [Book review] Lichens of the north woods: a field guide to 111 northern species, by Joe Walewski

    USGS Publications Warehouse

    Bennett, J.

    2007-01-01

    Review of: LICHENS OF THE NORTH WOODS, A FIELD GUIDE TO 111 NORTHERN SPECIES. Joe Walewski. 2007. North Woods Naturalist Series, Kollath & Stensaas Publishing, Duluth, Minnesota. 152 pp, softcover. ISBN: 0-9673793-50. $18.95.

  14. Magnetic and gravity anomaly patterns related to hydrocarbon fields in northern West Siberia

    SciTech Connect

    Piskarev, A.L.; Tchernyshev, M.Yu.

    1997-05-01

    A study of the features of gravity and magnetic fields in the vicinity of oil and gas reservoirs in West Siberia demonstrated a spatial relationship with the hydrocarbon deposits. The relevant magnetic and gravity anomalies cover approximately 900,000 km{sup 2} in northern West Siberia. Amplitude and frequency were investigated initially using double Fourier spectrum (DFS) analysis. This was followed by (1) application of transformations, filtering, and moving windows analysis; (2) compilation of maps of regional and local anomalies, and potential field derivatives; and (3) investigation of the distribution of parameters in areas of known deposits. Hydrocarbon deposits are located mostly at the slopes of positive regional gravity and magnetic anomalies which are interpreted as relating to deep riftogenic structures. At the same time, it is established that the location of hydrocarbon depositions coincides commonly with local gravity and magnetic minima generated by lows in basement density and magnetization. All known hydrocarbon deposits in northern West Siberia are in areas characterized by comparatively high gradients of constituent of gravity anomalies with a wavelength of about 90--100 km. These newly revealed links between reservoirs and potential field parameters may be a means to predict new discoveries in poorly explored territories and seas, primarily in Russia`s Arctic shelf.

  15. Reservoir development in Brahaney northwest and Patricia fields, northern Midland basin, Texas

    SciTech Connect

    Mazzullo, L.J.

    1990-02-01

    Porous pay zones in the Silurian-Devonian section of the northern Midland basin, Texas, vary stratigraphically, as well as structurally, with their locations beneath the pre-Woodford unconformity. These variations are related to at least two major periods of widespread pre-Woodford tectonism and erosion. A major unconformable surface, present at the top of the Lower Silurian Fusselman formation, was later modified by tectonism and erosion immediately preceding deposition of the Woodford Shale. In places where the Fusselman subcrops beneath the Woodford, its capacity for reservoir development is dependent upon the severity of geologic events that affected the formation during the two major tectonic/erosional events. Where the Wristen and Thirtyone formations subcrop, their reservoir capacity depends upon the extent of structuring and subsequent erosion immediately prior to Woodford deposition. Two pre-Woodford oil fields in the northern Midland basin illustrate geologic complexity that bears on the successful application of subsurface mapping in defining potential pay zones. Brahaney Northwest field in Yoakum County is productive from fractured, coarse crystalline Silurian-Devonian dolomites on subtle, fault-bounded structures. These structures, defined seismically on the base of the Woodford, do not reveal the more complex structural and stratigraphic variations within the reservoir itself. Patricia field in Dawson County is productive from Fusselman carbonates where upper Fusselman structural and topographic relief coincides with post-Woodford faulting and low-relief anticlinal closure as defined at the base of the Woodford.

  16. Improved Constraints on the Eruptive History of Northern Harrat Rahat Volcanic Field, Kingdom of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Stelten, M. E.; Downs, D. T.; Calvert, A. T.; Sherrod, D. R.; Hassan, K. H.; Muquyyim, F. A.; Ashur, M. S.

    2015-12-01

    Harrat Rahat is a large (~20,000 km2) alkalic volcanic field located in central western Saudi Arabia. A variety of eruptive products ranging from alkali basalt to trachyte have erupted at Harrat Rahat over the past ~10 m.y., with the most recent eruptions occurring at 641 CE (uncertain) and 1256 CE in the northern part of the volcanic field. Despite the field's young age and its close proximity to two major city centers, the eruptive history of Harrat Rahat remains poorly constrained. Previous researchers grouped the volcanic strata of northern Harrat Rahat into seven subunits based on limited K-Ar and 40Ar/39Ar dating, and on the degree of erosion displayed by the eruptive products. The youngest eruptive products (subunits Qm7 - Qm4) are thought to be ≤600 ka, whereas the older lavas (Qm3 - Qm1) are thought to be >600 ka. However, due to the sparse geochronologic control on the ages of the eruptive units, it remains unclear if the currently defined subunits accurately reflect the age distribution of lavas in northern Harrat Rahat. Additionally, the temporal relation between basaltic magmatism and the more evolved eruptive products has yet to be examined. To better constrain the eruptive history of Harrat Rahat we measured >50 new 40Ar/39Ar eruption ages for Qm1 through Qm5 lavas in northern Harrat Rahat. These new 40Ar/39Ar ages suggest that the majority of volcanism in the region occurred ≤400 ka and is significantly younger than previously thought, indicating that the magmatic system at Harrat Rahat has been more active over the past 400 kyr then previously recognized. Additionally, these new age data suggest that nearly all trachytic magmatism occurred <125 ka and was preceded by a pulse of more mafic magmatism. It is likely the magmatic system at Harrat Rahat reached an evolved state late in the history of the volcanic field due to increased and/or prolonged input of basaltic magmas into the crust.

  17. Potential field analysis images Paleoproterozoic terrane boundaries in the unexposed Northern Gawler Craton, Australia

    NASA Astrophysics Data System (ADS)

    Baines, G.; Giles, D.; Betts, P.; Backé, G.

    2008-12-01

    In areas of limited or zero basement exposure, potential field analysis provides an invaluable tool for determining the architecture continental cratons. We present an example from the Northern Gawler Craton, Australia. Here, the basement rocks are almost completely covered by Neoproterozoic and younger sedimentary rocks (with <<1% basement outcrop), so are amongst the least studied on the Australian continent. However, these rocks should preserve the best record of the Gawler Craton's interactions with neighbouring cratons during the amalgamation of Proterozoic Australia. We focus on the basement architecture in the Marla region of the northernmost Gawler Craton. We use geophysical techniques and apply a top-down approach to penetrate the significant thickness of cover and determine the structure of the unexposed northern Gawler Craton. The architecture, density and magnetic susceptibility of the overlying cover sequences are constrained from the surficial geology, borehole data and seismic reflection profiles. The effect of these cover sequences is then removed from gravity and magnetic data highlighting the basement structure. We then determine the architecture of the basement with depth from the potential field data by combining depth-to-source analyses, with forward and inverse modelling techniques constrained by petrophysical data from drill-holes. Results of this analysis include the observation of a major crustal boundary at the NE-SW trending Middle Bore Fault. To the NW of this boundary, crustal scale sources produce large gravity and magnetic anomalies. Whereas to the SE anomalies are sourced in the upper crust and overlie uniform middle to lower crust. We suggest that the Middle Bore Fault represents a boundary between allochthonous terranes that may have accreted to the Gawler craton during the Kimban Orogeny (~1.7 Ga) and the Archaean Gawler Craton that is overlain by Paleoproterozoic metasediments. The basement structure revealed by this approach

  18. Technological improvements in the field-based monitoring of glaciers in the Huasco basin, Northern Chile

    NASA Astrophysics Data System (ADS)

    Cisternas, Sebastián; Uribe, José; Carrión, Daniela; Rivera, Andrés; Corripio, Javier

    2014-05-01

    Difficulties with the terrain, weather conditions and accessibility makes high altitude field-based glacier monitoring (>4000 m.a.s.l) particularly challenging. Due to this field measurements are often incomplete and temporally limited when available. Given the importance of temporal analyses when monitoring glacierised environments (especially those that are directly influenced by human activities such as mining) the development and improvement of field-based monitoring techniques is thus essential. Here a series of field technologies are presented that are intended to improve the monitoring of glaciers in the Pascua Lama mining project, Northern Chile (29º18'S , 70º03'W). Efforts focus on monitoring changes in the energy balance and the spatial distribution of albedo variation over glacier surfaces. Technological innovations are described in the use of: (1) meteorological networks (automatic weather stations) - improved for better transmission in unfavourable weather conditions through the use of high frequency portions of the electromagnetic spectrum; (2) Non-metric fixed camera systems - improved to allow continuous monitoring of glacier albedo variations by using high frequency transmission over the Industrial, Scientific and Medical (ISM) band and low power servers based on ARM architecture. The implementation of these technologies has so far successfully improved data acquisition were applied and offers a robust alternative to the traditional field-based glacier monitoring methods used previously.

  19. A northern hemisphere geomagnetic field model for the last 14ka

    NASA Astrophysics Data System (ADS)

    Pavon-Carrasco, Fco Javier; Osete, Maria Luisa; Miquel Torta, Joan; de Santis, Angelo

    2013-04-01

    In this work, we propose a first regional geomagnetic field model for the Northern Hemisphere based on archaeomagnetic and lava flow data. The regional model, called scha.dif.14k, allows us to analyse the low degree of the geomagnetic field secular variation for the last 14000 years: from 12000 BC to 1900 AD. The inversion process of the declination, inclination and intensity palaeomagnetic data was carried out iteratively, using the spherical cap harmonic analysis (SCHA) up to degree K = 4 in space and penalized cubic B-spline in time with a knot point of 100 years for the whole time interval. Three starting models have been tested: a) A constant axial dipole field, b) a time-dependent axial dipole field and c) a time-dependent inclined dipole field. The last two starting models were estimated by using directly the archaeomagnetic data. These starting models have been perturbed in order to obtain a regional model with a higher spatial and temporal variability. We have compared the model with the recent published palaeosecular variation curves and with the global model for the Holocene: CALS10K.1b. Our model fits reasonably well the different palaeosecular variation curves and improves the prediction of the CALS10K.1b global model.

  20. High-performance super capacitors based on activated anthracite with controlled porosity

    NASA Astrophysics Data System (ADS)

    Lee, Hyun-Chul; Byamba-Ochir, Narandalai; Shim, Wang-Geun; Balathanigaimani, M. S.; Moon, Hee

    2015-02-01

    Mongolian anthracite is chemically activated using potassium hydroxide as an activation agent to make activated carbon materials. Prior to the chemical activation, the chemical agent is introduced by two different methods as follows, (1) simple physical mixing, (2) impregnation. The physical properties such as specific surface area, pore volume, pore size distribution, and adsorption energy distribution are measured to assess them as carbon electrode materials for electric double-layer capacitors (EDLC). The surface functional groups and morphology are also characterized by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) analyses respectively. The electrochemical results for the activated carbon electrodes in 3 M sulfuric acid electrolyte solution indicate that the activated Mongolian anthracite has relatively large specific capacitances in the range of 120-238 F g-1 and very high electrochemical stability, as they keep more than 98% of initial capacitances until 1000 charge/discharge cycles.

  1. Electric conductivity and aggregation of anthracite and graphite particles in concretes

    SciTech Connect

    E.A. Fanina; A.N. Lopanov

    2009-02-15

    A statistical model of the electric conductivity of a heterogeneous system based on coal and a binding agent is presented. In this system, a conductive phase appears because of particle aggregation. The model was tested in the systems of anthracite and graphite in cement stone. The consistency between the experimental and calculated electric conductivities with a correlation coefficient higher than 0.9 was found on a linear interpolation of model parameters. It was found that the presence of a surfactant (cetylpyridinium chloride) and a high-molecular-weight compound (polyvinyl acetate) changed the number of particles in anthracite and graphite aggregates to affect the specific conductivity of the heterogeneous system. 9 refs., 5 figs., 1 tab.

  2. An Evaluation Study: Sand-Anthracite, Modular Filtration Unit (SAMFU). Phase I.

    DTIC Science & Technology

    1986-10-01

    media has a specific gravity approxi- mately 1/2 that of sand, which will reduce filter weight to the extent it replaces sand. I <I 41 4>- ftUL...prevent media loss during tiltration and backwash B) Determine the feasibility of using shallow depth, modular anthracite filters for solids removal C...rigidity and strength. 5. Provide adequate depth and surface area of media for experimental purposes. A) Module surface area was made square in

  3. Experimental study on combustion characteristics and NOX emissions of pulverized anthracite preheated by circulating fluidized bed

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Zhu, Jian-Guo; Lu, Qing-Gang

    2011-08-01

    A 30 kW bench-scale rig of pulverized anthracite combustion preheated by a circulating fluidized bed (CFB) was developed. The CFB riser has a diameter of 90 mm and a height of 1,500 mm. The down-fired combustion chamber (DFCC) has a diameter of 260 mm and a height of 3,000 mm. Combustion experiments were carried out using pulverized anthracite with 6.74% volatile content. This low volatile coal is difficult to ignite and burn out. Therefore, it requires longer burnout time and higher combustion temperature, which results in larger NOX emissions. In the current study, important factors that influence the combustion characteristics and NOX emissions were investigated such as excess air ratio, air ratio in the reducing zone, and fuel residence time in the reducing zone. Pulverized anthracite can be quickly preheated up to 800°C in CFB when the primary air is 24% of theoretical air for combustion, and the temperature profile is uniform in DFCC. The combustion efficiency is 94.2%, which is competitive with other anthracite combustion technologies. When the excess air ratio ranges from 1.26 to 1.67, the coal-N conversion ratio is less than 32% and the NOX emission concentration is less than 371 mg/m3 (@6% O2). When the air ratio in the reducing zone is 0.12, the NOX concentration is 221 mg/m3 (@6% O2), and the coal-N conversion ratio is 21%, which is much lower than that of other boilers.

  4. Northern elephant seal field bioacoustics and aerial auditory masked hearing thresholds in three pinnipeds

    NASA Astrophysics Data System (ADS)

    Southall, Brandon Lee

    This dissertation comprises four interrelated studies on acoustic communication (including both signal production and signal reception) in pinnipeds, primarily northern elephant seals (Mirounga angustirostris). Field measurements of vocalization parameters were obtained in elephant seal breeding rookeries. Additionally, auditory masking experiments were conducted with individuals representing three pinniped species, including a northern elephant seal. This study quantified how aerial noise masks aerial hearing and provided preliminary data on auditory frequency filtering. All of these studies were conducted in air for a variety of practical and theoretical reasons. Some governmental, media, and research organizations have recently become concerned with the impacts of underwater anthropogenic noise on aquatic animals. However, little consideration has been given to the dual pressures imposed by aerial and underwater noise on amphibious marine mammals such as the pinnipeds. This dissertation sought to provide some basic data bearing on this matter by investigating aerial signals and aerial masked hearing. Data were obtained on aerial vocalization source levels, signal directivity patterns, natural aerial ambient noise, signal propagation properties, multi-modal aspects of signaling, motivation-specific signal variability, aerial critical masking ratios, and auditory filter bandwidths. The results indicate that different signal components may be more readily detectable in variable noise conditions, frequency resolution likely affects detection ranges, developmental and motivational factors affect signal parameters, and that some pinnipeds apparently detect signals over masking noise relatively well both in air and water. Using the northern elephant seal as a representative model, a model for quantifying constraints on vocal communication was developed to provide first-order predictions about detection ranges for signals in variable noise conditions.

  5. Study on CO₂ gasification properties and kinetics of biomass chars and anthracite char.

    PubMed

    Wang, Guangwei; Zhang, Jianliang; Hou, Xinmei; Shao, Jiugang; Geng, Weiwei

    2015-02-01

    The CO2 gasification properties and kinetics of three biomass chars (WS-char, RL-char and PS-char) and anthracite char (AC-char) were investigated by thermogravimetric analysis method. Three nth-order representative gas-solid reaction models, random pore model (RPM), volume reaction model (VM) and unreacted core model (URCM) were employed to describe the reactive behavior of chars. Results show that gasification reactivity order of different chars from high to low was WS-char, PS-char, RL-char and AC-char. In addition, the chemical components as well as physical structures of four chars were systematically tested. It was found that gasification properties of char were determined by carbonaceous structure. It was concluded from kinetics analysis that RPM model was the best model for describing the reactivities of biomass chars and VM was the model that best fitted the gasification process of anthracite char. The activation energies obtained for the biomass and anthracite char samples lie in the range of 236.4-284.9 kJ/mol. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Geological history and petroleum system of the Mittelplate oil field, Northern Germany

    NASA Astrophysics Data System (ADS)

    Grassmann, S.; Cramer, B.; Delisle, G.; Messner, J.; Winsemann, J.

    2005-12-01

    The geological history of Germany’s largest and most productive petroleum accumulation, the Mittelplate oil field in Schleswig-Holstein (Northern Germany), is reconstructed by simulating the structural and thermal evolution along a 2D cross-section. The Mittelplate field is located at the western flank of the Büsum salt dome at the transition from the Schleswig-Holstein mainland to the German North Sea Sector. Organic geochemical data confirm the Lower Jurassic Posidonia Shale to be the predominant oil source rock in the Schleswig-Holstein area. The studied section is characterized by salt walls and salt domes built up by Permian evaporites. Reconstruction of the structural and thermal evolution of the Mittelplate field by means of basin modelling reveals the dominating influence of salt dynamics on the entire petroleum system: The development of secondary rim-synclines during salt rise provided accommodation space for the deposition of the Posidonia Shale as well as the deltaic Middle Jurassic reservoir sandstones. The rise of the nearby Oldenswort salt wall controlled the timing of maturation and petroleum generation during Cenozoic times. Hydrocarbon migration from the Posidonia Shale into the reservoirs occurred up-dip from the deeper subsiding rim-syncline into the structural trap with the Middle Jurassic reservoir sandstones pinching out at the flank of the Büsum salt dome. Along the modelled 2D section the field’s recent temperature field and its complex reservoir architecture are reconstructed.

  7. Geology and coastal hazards in the northern Monterey Bay, California: field trip guidebook, November 4, 2000

    USGS Publications Warehouse

    Hapke, Cheryl

    2000-01-01

    The purpose of this field trip is to explore the relationships between local geology, coastal hazards, and human influences in the northern Monterey Bay, which is a tectonically active high wave energy coastal environment. Seacliffs, shore platforms, pocket beaches and a headland/embayment morphology characterize this rocky coastline. Many studies of the onshore and offshore geology and geophysics, the local wave climate, and the effects of large storm events and earthquakes on the coastline have been conducted in this region (see Related Reading section). This field trip summarizes many of the findings of these research investigations, and also considers the relationship between the rates and styles of seacliff erosion and the variations in the local geology. The field trip stops allow the participant to examine seacliff sites of different geological lithologies, geographic orientations, and varying protection from wave attack, and consider how these variables affect not only the rate or magnitude of seacliff retreat but also the styles of retreat. In general the two primary forcing factors in the retreat of seacliffs are marine and terrestrial processes. At the various field trip stops, the relative importance of these processes in shaping the coastline at that particular location will be explored. Where beaches have developed, whether naturally or by emplacement of man-made structures, field trip stops are designed to look at the occurrence of the beaches (why they exist where they do) and to understand the response of the beaches to large storm events. Finally, this trip focuses on the various coastline protection structures that have been built in the area, and their effectiveness in protecting development on the beaches or at the tops of the seacliffs. The first stop of the trip is the Long Marine Lab facility where the seacliffs are composed of the most resistant geological unit in the area, the Miocene Santa Cruz Mudstone. This stop also includes discussion

  8. Field evaluation of commercial repellent formulations against mosquitoes (Diptera: Culicidae) in Northern Territory, Australia.

    PubMed

    Frances, S P; Waterson, D G E; Beebe, N W; Cooper, R D

    2005-12-01

    Field trials comparing commercially available repellent formulations containing picaridin (1-piperidinecarboxylate acid, 2-(2-hydroxyethyl)-1-methylpropylester) and deet (N,N-diethyl-3-methylbenzamide) against mosquitoes in Northern Territory, Australia, were conducted. Three repellents were compared: Autan Repel containing 9.3% picaridin, RID containing 10% deet, and Bushman Ultra containing 80% deet in a gel. The predominant mosquito species collected were Culex annulirostris Skuse (63.2%), Ochlerotatus normanensis (Taylor) (19.6%), and Anopheles meraukensis Venhuis (8.6%). Autan Repel provided >95% protection against all mosquitoes for 2 h, RID for 7 h, and Bushman for >8 h. Against Cx. annulirostris, Autan Repel provided >95% protection for 5 h, RID for 7 h, and Bushman for >8 h. The study showed that both deet formulations provided significantly better protection against mosquitoes than picaridin (Autan Repel). All 3 repellents provided good protection against Cx. annulirostris, an important vector of arboviruses in Australia.

  9. Estimates of the seasonal mean vertical velocity fields of the extratropical Northern Hemisphere

    NASA Technical Reports Server (NTRS)

    White, G. H.

    1983-01-01

    Indirect methods are employed to estimate the wintertime and summertime mean vertical velocity fields of the extratropical Northern Hemisphere and intercomparisons are made, together with comparisons with mean seasonal patterns of cloudiness and precipitation. Twice-daily NMC operational analyses produced general circulation statistics for 11 winters and 12 summers, permitting calculation of the seasonal NMC averages for 6 hr forecasts, solution of the omega equation, integration of continuity equation downward from 100 mb, and solution of the thermodynamic energy equation in the absence of diabatic heating. The methods all yielded similar vertical velocity patterns; however, the magnitude of the vertical velocities could not be calculated with great accuracy. Orography was concluded to have less of an effect in summer than in winter, when winds are stronger.

  10. Science teachers as metascientists: an inductive-deductive dialectic immersion in northern alpine field ecology

    NASA Astrophysics Data System (ADS)

    Bencze, Larry; Elshof, Leo

    2004-12-01

    Efforts to promote more realistic conceptions about science are often limited by teachers' inexperience in this domain. In this paper, we describe an 'inductive-deductive, dialectic immersion' approach towards assisting teachers in developing more realistic conceptions about science -- along with corresponding revised perspectives about science teaching. Three secondary teachers of science with minimal science research experience engaged in a case study of science in action -- specifically, in an episode of northern alpine ecological field research. Qualitative data analyzed by constant comparative methods suggested that these teachers shifted along a modernist through postmodernist continuum -- as indicated by increased support for a more Naturalist epistemology of science, a more Antirealist ontology of science, and corresponding priorities towards science teaching and learning. Results suggest that teachers of science can develop postmodern views about science and science teaching if given opportunities to induce and deduce propositions about science in realistic cases of science in action.

  11. Field evidences for a Mesozoic palaeo-relief through the northern Tianshan

    NASA Astrophysics Data System (ADS)

    Gumiaux, Charles; Chen, Ke; Augier, Romain; Chen, Yan; Wang, Qingchen

    2010-05-01

    The modern Tianshan mountain belt, located in Central Asia, offers a natural laboratory to study orogenic processes linked with convergent geodynamical settings. Most of the previous studies either focused on the Paleozoic evolution of the range - subductions, arc accretions and continental collision - or on its Cenozoic intra-continental evolution linked with the India-Asia collision. At first order, the finite structure of this range obviously displays a remarkable uprising of Paleozoic "basement" rocks - as a crustal-scale ‘pop-up' - surrounded by two Cenozoic foreland basins. The present-day topography of the Tianshan is traditionally related to the latest intra-continental reactivation of the range. In contrast, the present field study of the northern Tianshan brings new and clear evidences for the existence of a significant relief, in this area, during Mesozoic times. The investigation zone is about 250 km long, from Wusu to Urumqi, along the northern flank of the Tianshan where the rivers deeply incised the topography. In such valleys, lithologies and structural relationships between Paleozoic basement rocks, Mesozoic and Cenozoic sedimentary series are particularly well exposed along several sections. Jurassic series are mostly characterized by coal-bearing, coarse-grained continental deposits. Within intra-mountain basins, sedimentary breccias, with clasts of Carboniferous basement rocks, have been locally found at the base of the series. This argues for the presence of a rather proximal palaeo-relief of basement rocks along the range front and the occurrence of proximal intra-mountain basins, during the Jurassic. Moreover, while a major thrust is mostly evoked between Jurassic deposits and the Paleozoic units, some of the studied sections show that the Triassic to Jurassic sedimentary series can be followed from the basin to the range. In these cases, the unconformity of the Mesozoic series on top of the Carboniferous basement has been locally clearly

  12. Structure and flow-induced variability of the subtidal salinity field in northern San Francisco Bay

    USGS Publications Warehouse

    Monismith, Stephen G.; Kimmerer, W.; Burau, J.R.; Stacey, M.T.

    2002-01-01

    The structure of the salinity field in northern San Francisco Bay and how it is affected by freshwater flow are discussed. Two datasets are examined: the first is 23 years of daily salinity data taken by the U.S. Bureau of Reclamation along the axis of northern San Francisco Bay: the second is a set of salinity transects taken by the U.S. Geological Survey between 1988 and 1993. Central to this paper is a measure of salinity intrusion. X2: the distance from the Golden Gate Bridge to where the bottom salinity is 2 psu. Using X2 to scale distance, the authors find that for most flow conditions, the mean salinity distribution of the estuary is nearly self-similar with a salinity gradient in the center 70% of the region between the Golden Gate and X2 that is proportional to X2-1. Analysis of covariability of Q and X2 showed a characteristics timescale of adjustment of the salinity field of approximately 2 weeks. The steady-state response deduced from the X2 time series implies that X2 is proportional to riverflow to the 1/7 power. This relation, which differs from the standard 1/3 power dependence that is derived theoretically assuming constant exchange coefficients, shows that the upstream salt flux associated with gravitational circulation is more sensitive to the longitudinal salinity gradient than theory supposes. This is attributed to the strengthening of stratification caused by the stronger longitudinal salinity gradient that accompanies larger river flows.

  13. Neogene carbonate exploration play concepts for Northern New Guinea: New iteration from field work and seismic stratigraphy along the Northern New Guinea Fault Zone

    SciTech Connect

    Pigott, J.D.; Geiger, C. )

    1994-07-01

    Recent field reconnaissance, petrography, nanno and foraminifera age determinations, and seismic stratigraphy of the Sepik and Piore subbasins of northern New Guinea reveal the existence of an extensive, tectonically unstable, Miocene-Pliocene carbonate shelf system. These findings represent the first recorded evidence of northern Papuan limestones coeval in age to those of the hydrocarbon productive Salawati Basin of Irian Jaya. Moreover, these observations also demonstrate the significance of episodic activities of the northern New Guinea fault zone upon the changes in carbonate sedimentation and diagenesis. During the Neogene, algal biosparites to foraminiferal biomicrites defined the clean portion of a mixed clastic-carbonate shelf system of the northern New Guinea basin, which began at the central New Guinea cordillera and deepened northward. This shelf was interrupted by coral-coralline algal boundstone fringing- to patch-reef buildups with associated skeletal grainstones. Clean carbonates were spatially and temporally restricted to basement blocks, which episodically underwent uplift while terrigenous dilutes carbonates were more common in adjacently subsiding basement block bathymetric lows. These tectonic expressions were caused by the spatially transient nature of constraining bends of the evolving north New Guinea faults. As shown by seismic stratigraphy, by the late Miocene to the early Pliocene the uplift of the Bewani-Torricelli Mountains sagittally divided the shelf of the northern New Guinea basin into the Ramu-Sepik and the Piore basins. Continued regional sinistral transpression between the Pacific and the New Guinea leading edge of the Indo-Australian plates led to the reverse tilting of the Piore basin, the shallowing of the former distal shelf with concomitant extensive biolithite development (e.g., on subsiding volcanic islands) eventual uplifting of the Oenake Range, and en echelon faulting of the Bewani-Torricelli Mountains.

  14. Field-aligned currents in Saturn's northern nightside magnetosphere: Evidence for interhemispheric current flow associated with planetary period oscillations

    NASA Astrophysics Data System (ADS)

    Hunt, G. J.; Cowley, S. W. H.; Provan, G.; Bunce, E. J.; Alexeev, I. I.; Belenkaya, E. S.; Kalegaev, V. V.; Dougherty, M. K.; Coates, A. J.

    2015-09-01

    We investigate the magnetic perturbations associated with field-aligned currents observed on 34 Cassini passes over the premidnight northern auroral region during 2008. These are found to be significantly modulated not only by the northern planetary-period oscillation (PPO) system, similar to the southern currents by the southern PPO system found previously, but also by the southern PPO system as well, thus providing the first clear evidence of PPO-related interhemispheric current flow. The principal field-aligned currents of the two PPO systems are found to be co-located in northern ionospheric colatitude, together with the currents of the PPO-independent (subcorotation) system, located between the vicinity of the open-closed field boundary and field lines mapping to ~9 Saturn radius (Rs) in the equatorial plane. All three systems are of comparable magnitude, ~3 MA in each PPO half-cycle. Smaller PPO-related field-aligned currents of opposite polarity also flow in the interior region, mapping between ~6 and ~9 Rs in the equatorial plane, carrying a current of ~ ±2 MA per half-cycle, which significantly reduce the oscillation amplitudes in the interior region. Within this interior region the amplitudes of the northern and southern oscillations are found to fall continuously with distance along the field lines from the corresponding hemisphere, thus showing the presence of cross-field currents, with the southern oscillations being dominant in the south, and modestly lower in amplitude than the northern oscillations in the north. As in previous studies, no oscillations related to the opposite hemisphere are found on open field lines in either hemisphere.

  15. Field evaluation of repellent formulations containing deet and picaridin against mosquitoes in Northern Territory, Australia.

    PubMed

    Frances, S P; Waterson, D G E; Beebe, N W; Cooper, R D

    2004-05-01

    Field efficacy of repellent formulations containing picaridin (1-methyl-propyl 2-(2-hydroxyethyl)-1-piperidinecarboxylate) or deet (N,N,-diethyl-3-methylbenzamide) against mosquitoes in Northern Territory, Australia, was evaluated. The following repellent treatments were evaluated: 19.2% picaridin (Autan Repel Army 20), a solution of 20% deet in ethanol, and 35% deet in a gel (Australian Defense Force [ADF]). The predominant mosquito species were Culex annulirostris Skuse (57.8%), Anopheles merankensis Venhuis (15.4%), and Anopheles bancroftii Giles (13.2%). The protection provided by repellents against Anopheles spp. was relatively poor, with 19.2% picaridin and ADF deet providing >95% protection for only 1 h, whereas 20% deet provided <95% protection at 1 h after repellent application. In contrast, the repellents provided good protection against Cx. annulirostris, with 19.2% picaridin providing >95% protection for 5 h and both deet formulations providing >95% protection for 7 h when collections ceased. This study provides additional field data showing tolerance of Anopheles spp. for repellents. The response of field populations of Cx. annulirostris, an important vector of arboviruses in Australia, to repellents containing deet and picaridin is reported for the first time.

  16. Anthracite coal shortages. Hearing before the Subcommittee on Energy and Mineral Resources of the Committee on Energy and Natural Resources, United States Senate, Ninety-Seventh Congress, First Session

    SciTech Connect

    Not Available

    1981-01-01

    Purpose of this hearing is to make a candid assessment of the feasibility of using anthracite coal instead of heating oil in homes, particularly in the Northeast, and of the potential contribution of anthracite coal to the residential market. (DLC)

  17. Comparison of quartz sand, anthracite, shale and biological ceramsite for adsorptive removal of phosphorus from aqueous solution.

    PubMed

    Jiang, Cheng; Jia, Liyue; Zhang, Bo; He, Yiliang; Kirumba, George

    2014-02-01

    The choice of substrates with high phosphorus adsorption capacity is vital for sustainable phosphorus removal from waste water in constructed wetlands. In this study, four substrates were used: quartz sand, anthracite, shale and biological ceramsite. These substrate samples were characterized by Xray diffractometry and scanning electron microscopy studies for their mineral components (chemical components) and surface characteristics. The dynamic experimental results revealed the following ranking order for total phosphorus (TP) removal efficiency: anthracite > biological ceramsite > shale > quartz sand. The adsorptive removal capacities for TP using anthracite, biological ceramsite, shale and quartz sand were 85.87, 81.44, 59.65, and 55.98 mg/kg, respectively. Phosphorus desorption was also studied to analyze the substrates' adsorption efficiency in wastewater treatment as well as the substrates' ability to be reused for treatment. It was noted that the removal performance for the different forms of phosphorus was dependent on the nature of the substrate and the adsorption mechanism. A comparative analysis showed that the removal of particulate phosphorus was much easier using shale. Whereas anthracite had the highest soluble reactive phosphorus (SRP) adsorptive capacity, biological ceramsite had the highest dissolved organic phosphorus (DOP) removal capacity. Phosphorus removal by shale and biological ceramsite was mainly through chemical adsorption, precipitation or biological adsorption. On the other hand, phosphorus removal through physical adsorption (electrostatic attraction or ion exchange) was dominant in anthracite and quartz sand.

  18. Alteration mineral mapping for iron prospecting using ETM+ data, Tonkolili iron field, northern Sierra Leone

    NASA Astrophysics Data System (ADS)

    Mansaray, Lamin R.; Liu, Lei; Zhou, Jun; Ma, Zhimin

    2013-10-01

    The Tonkolili iron field in northern Sierra Leone has the largest known iron ore deposit in Africa. It occurs in a greenstone belt in an Achaean granitic basement. This study focused mainly on mapping areas with iron-oxide and hydroxyl bearing minerals, and identifying potential areas for haematite mineralization and banded iron formations (BIFs) in Tonkolili. The predominant mineral assemblage at the surface (laterite duricrust) of this iron field is haematitegoethite- limonite ±magnetite. The mineralization occurs in quartzitic banded ironstones, layered amphibolites, granites, schists and hornblendites. In this study, Crosta techniques were applied on Enhanced Thematic Mapper (ETM+) data to enhance areas with alteration minerals and target potential areas of haematite and BIF units in the Tonkolili iron field. Synthetic analysis shows that alteration zones mapped herein are consistent with the already discovered magnetite BIFs in Tonkolili. Based on the overlaps of the simplified geological map and the remote sensing-based alteration mineral maps obtained in this study, three new haematite prospects were inferred within, and one new haematite prospect was inferred outside the tenement boundary of the Tonkolili exploration license. As the primary iron mineral in Tonkolili is magnetite, the study concludes that, these haematite prospects could also be underlain by magnetite BIFs. This study also concludes that, the application of Crosta techniques on ETM+ data is effective not only in mapping iron-oxide and hydroxyl alterations but can also provide a basis for inferring areas of potential iron resources in Algoma-type banded iron formations (BIFs), such as those in the Tonkolili field.

  19. A climatic trigger for the giant Troll pockmark field in the northern North Sea

    NASA Astrophysics Data System (ADS)

    Mazzini, Adriano; Svensen, Henrik H.; Forsberg, Carl Fredrik; Linge, Henriette; Lauritzen, Stein-Erik; Haflidason, Haflidi; Hammer, Øyvind; Planke, Sverre; Tjelta, Tor Inge

    2017-04-01

    Pockmarks are seafloor craters usually formed during methane release on continental margins. However, the mechanisms behind their formation and dynamics remain elusive. Here we report detailed investigations on one of the World's largest pockmark fields located in the Troll region in the northern North Sea. Seafloor investigations show that >7000 pockmarks are present in a ∼600 km2 area. A similar density of pockmarks is likely present over a 15,000 km2 region outside our study area. Based on extensive monitoring, coring, geophysical and geochemical analyses, no indications of active gas seepage were found. Still, geochemical data from carbonate blocks collected from these pockmarks indicate a methanogenic origin linked to gas hydrate dissociation and past fluid venting at the seafloor. We have dated the carbonates using the U-Th method in order to constrain the pockmark formation. The carbonates gave an isochron age of 9.59 ± 1.38 ka, i.e. belonging to the initial Holocene. Moreover, radiocarbon dating of microfossils in the sediments inside the pockmarks is consistent with the ages derived from the carbonates. Based on pressure and temperature modelling, we show that the last deglaciation could have triggered dissociation of gas hydrates present in the region of the northern part of the Norwegian Channel, causing degassing of 0.26 MtCH4/km2 at the seafloor. Our results stress the importance of external climatic forcing of the dynamics of the seafloor, and the role of the rapid warming following the Younger Dryas in pacing the marine gas hydrate reservoir.

  20. Early Pottery Making in Northern Coastal Peru. Part II: Field Firing Experiments

    NASA Astrophysics Data System (ADS)

    Shimada, I.; Goldstein, D.; Sosa, J.; Wagner, U.

    2003-09-01

    We present data from three seasons of experimental field work designed to recreate ancient Andean coastal ceramic firing techniques. Based on the recent discovery of two different archaeological ceramic production sites in the La Leche river valley of northern coastal Peru, the opportunity arose to apply Mössbauer spectroscopy and other analytical methods to reconstruct ancient firing procedures. Two sets of firings took place in 1993 and 1997 in Batán Grande using a partially restored Formative kiln from about 800 BC, local hardwood and cow dung as fuel. A third experiment followed in 2000 after the discovery of a Middle Sicán ceramics workshop in use between ca. AD 950 and 1050 at Huaca Sialupe, where an exact replica of an ancient kiln was built from local clay, and fired with local wood and cow dung. Additionally, inverted urns found at Huaca Sialupe were tested for their potential use as furnaces for metal working. Mössbauer spectroscopy was used to compare the physical and chemical state of specimens produced in the field experiments with ancient ceramics and with specimens produced in controlled laboratory experiments.

  1. Tertiary fluvial systems within the Bear Creek coal field, northern Big Horn basin, Montana

    SciTech Connect

    Weaver, J.N. ); Gruber, J.R. Jr. )

    1991-06-01

    The Bear Creek coal field contains the 250-m-thick coal-bearing Paludal Member of the Paleocene Fort Union Formation in the northern Big Horn Basin, Montana. Detailed field and subsurface data show two contrasting geometries in alluvial strata, each bounded by an economic coal bed. The lower 50 m of the Paludal Member is dominated by sheet and ribbon sandstones. The sheet sandstones are as long as 1.5 km and fine upwards from medium to fine grained. Some sandstones are multistory with sharp upoper and lower contacts. The upper portion has convolute bedding, ripple lamination, and some horizontal and tabular crossbeds. Stratigraphically higher is a 12-m-thick fine-grained sequence, containing large tree trunks in growth position and extensively rooted mud rocks. Sandstone bodies, 6 m thick and 10 m wide, are enclosed within mudstones and siltstones. The sandstones are primarily ripple laminated and have stepped bases and internal erosion surfaces. This interval has previously been interpreted as deposits of an anastomosed fluvial system. The sandstones show little evidence of significant lateral migration. In contrast to the lower interval, the environment here consisted of well-developed vegetated islands separating fluvial channels. Subsurface data show that the major coal beds are laterally continuous within the study area. The cyclic development of the coals reflects intermittent periods of long-term basin stability. Alternating dominance of the sandstones suggests that influx and distribution were controlled through episodic uplift of the nearby Beartooth Mountains.

  2. [Coating modification of anthracite substrates in vertical-flow constructed wetlands by LDHs synthesized from different metal compounds and the nitrogen removal efficiencies].

    PubMed

    Zhang, Xiang-Ling; Guo, Lu; Chen, Jun-Jie; Liu, Xiao-Ting; Xu, Lu; Chen, Qiao-Zhen; Wang, Xiao-Xiao

    2014-08-01

    As one kind of vertical-flow constructed wetlands substrates, anthracite was selected in this experiment. LDHs (layered double hydroxides) were synthesized in alkaline conditions by co-precipitation of different kinds of metal compounds, such as CaCl2, ZnCl2, MgCl2, FeCl3, AlCl3, CoCl3. The synthesized LDHs were in-situ coated onto the surface of anthracite substrate to achieve the aim of modification. Simulated test columns were constructed to study the nitrogen removal efficiency of the urban sewage using the original anthracite substrates and 9 kinds of modified anthracite substrates. The results showed that: LDHs synthesized by all the 9 different kinds of methods could effectively modify the anthracite substrate by in-situ coating. With Mg2+ involved in the synthesis of modified substrates, good TN and ammonia nitrogen removal efficiencies were observed. The modified anthracite substrates coated with MgCo-LDHs had the optimal performance with average TN and ammonia nitrogen removal efficiencies of higher than 80% and 85%, respectively. The ammonia nitrogen removal efficiencies by the modified anthracite substrates coated by LDHs reacted with Mg2+ and Fe3+ were also high. The ammonia nitrogen removal efficiencies by modified anthracite substrates coated with CaFe-LDHs and MgFe-LDHs were higher than 85%.

  3. Reconstructing Northern Hemisphere upper-level fields during World War II

    NASA Astrophysics Data System (ADS)

    Brönnimann, S.; Luterbacher, J.

    Monthly mean fields of temperature and geopotential height (GPH) from 700 to 100 hPa were statistically reconstructed for the extratropical Northern Hemisphere for the World War II period. The reconstruction was based on several hundred predictor variables, comprising temperature series from meteorological stations and gridded sea level pressure data (1939-1947) as well as a large amount of historical upper-air data (1939-1944). Statistical models were fitted in a calibration period (1948-1994) using the NCEP/NCAR Reanalysis data set as predictand. The procedure consists of a weighting scheme, principal component analyses on both the predictor variables and the predictand fields and multiple regression models relating the two sets of principal component time series to each other. According to validation experiments, the reconstruction skill in the 1939-1944 period is excellent for GPH at all levels and good for temperature up to 500 hPa, but somewhat worse for 300 hPa temperature and clearly worse for 100 hPa temperature. Regionally, high predictive skill is found over the midlatitudes of Europe and North America, but a lower quality over Asia, the subtropics, and the Arctic. Moreover, the quality is considerably better in winter than in summer. In the 1945-1947 period, reconstructions are useful up to 300 hPa for GPH and, in winter, up to 500 hPa for temperature. The reconstructed fields are presented for selected months and analysed from a dynamical perspective. It is demonstrated that the reconstructions provide a useful tool for the analysis of large-scale circulation features as well as stratosphere-troposphere coupling in the late 1930s and early 1940s.

  4. Effect of air-staging on anthracite combustion and NOx formation

    SciTech Connect

    Weidong Fan; Zhengchun Lin; Youyi Li; Jinguo Kuang; Mingchuan Zhang

    2009-01-15

    Experiments were carried out in a multipath air inlet one-dimensional furnace to assess NOx emission characteristics of the staged combustion of anthracite coal. These experiments allowed us to study the impact of pulverized coal fineness and burnout air position on emission under both deep and shallow air-staged combustion conditions. We also studied the impact of char-nitrogen release on both the burning-out process of the pulverized coal and the corresponding carbon content in fly ash. We found that air-staged combustion affects a pronounced reduction in NOx emissions from the combustion of anthracite coal. The more the air is staged, the more NOx emission is reduced. In shallow air-staged combustion (f{sub M} = 0.85), the fineness of the pulverized coal strongly influences emissions, and finer coals result in lower emissions. Meanwhile, the burnout air position has only a weak effect. In the deep air-staged combustion (f{sub M} = 0.6), the effect of coal fineness is smaller, and the burnout air position has a stronger effect. When the primary combustion air is stable, NOx emissions increase with increasing burnout air. This proves that, in the burnout zone, coal char is responsible for the discharge of fuel-nitrogen that is oxidized to NOx. The measurement of secondary air staging in a burnout zone can help inhibit the oxidization of NO caused by nitrogen release. Air-staged combustion has little effect on the burnout of anthracite coal, which proves to be suitable for air-staged combustion. 31 refs., 11 figs., 1 tab.

  5. CFB combustion of high-ash Ukrainian anthracite -- Pilot testing and design implications

    SciTech Connect

    Belin, F.; Fuller, T.A.; Maryamchik, M.; Perna, M.A.; Maystrenko, A.Yu.

    1997-12-31

    High-ash anthracite is the most important indigenous fuel used for power generation in Ukraine. The power plant upgrade program, developed jointly by US Department of Energy (DOE) and Ukrainian Ministry of Energy, anticipates applying the CFB technology for efficient and environmentally clean utilization of this hard-to-burn fuel. Testing of high-ash anthracite sponsored by DOE was conducted at CFB test facilities at the Division of High Temperature Energy Conversion (DHTEC) of Ukrainian Academy of Science in Kiev and at the Babcock and Wilcox Research Center in Alliance, Ohio, USA (ARC). Testing at DHTEC included kinetic studies and combustion tests on a small-scale (100 mm diameter) CFB combustor. The rest results were used to select the fuel sizing and limestone type for pilot testing at ARC and to evaluate the effects of operating parameters on fuel combustion. Testing at the ARC 2.5 MW{sub t} CFB pilot facility (700 x 700 mm cross section, 23 m high) provided combustion and emission performance data applicable for designing of commercial-scale CFB boilers. Stable combustion without supplemental fuel and with the unburned carbon loss of less than 3% was achieved over a 55 to 100% load range. About 90% of sulfur was removed by adding limestone at a Ca/S ratio of 1.85; nitrogen oxide and carbon monoxide emissions were below 340 mg/Nm{sup 3} and 260 mg/Nm{sup 3}, respectively. The CFB boiler design recommendations for high-ash anthracite, developed based on the test results, are described in the paper.

  6. Enhanced Oxidative Reactivity for Anthracite Coal via a Reactive Ball Milling Pretreatment Step

    SciTech Connect

    Angela D. Lueking; Apurba Sakti; Dania Alvarez-Fonseca; Nichole Wonderling

    2009-09-15

    Reactive ball milling in a cyclohexene solvent significantly increases the oxidative reactivity of an anthracite coal, due to the combined effects of particle size reduction, metal introduction, introduction of volatile matter, and changes in carbon structure. Metals introduced during milling can be easily removed via a subsequent demineralization process, and the increased reactivity is retained. Solvent addition alters the morphological changes that occur during pyrolysis and leads to a char with significantly increased reactivity. When the solvent is omitted, similar effects are seen for the milled product, but a significant fraction of the char is resistant to oxidation. 33 refs., 3 figs., 1 tab.

  7. Improvement of stability and efficiency of combustion for low rank anthracite

    SciTech Connect

    Chen, G.; Qiu, J.; Zhang, Z.; Li, F.; Sun, X.

    1994-12-31

    A new kind of burner, bluff-body with cavity burner, which is based on the bluff-body burner is developed in this paper. The three dimension mean velocity and turbulent characteristics have been measured in the burner`s recirculation zone by using three dimension laser dynamics analysis. For a low rank anthracite, combustion test shows this burner is better than bluff-body in ignition and flame stability. 50 MW(220T/H) boiler operation show that the temperature in the flame zone is high, combustion is very stable and the efficiency is increased when this burner is used.

  8. Late Permian age of ammonium-bearing illite in Pennsylvania anthracites: Temporal constraints on coalification in the central Appalachians

    SciTech Connect

    Daniels, E.J.

    1996-12-31

    K/Ar dating of authigenic NH4-bearing illite in coal from the Anthracite region of eastern Pennsylvania yields apparent ages of 253-236 Ma ({+-}8 m.y.). The oldest K/Ar date of 253 Ma ({+-}8 m.y.) is a minimum age for the thermal event associated with anthracite formation and illite authigenesis. This date is probably within {approx}10 m.y. of the time at which coal-bearing rocks experienced peak temperatures, which suggests an age range of 265-255 Ma for this event. Age dates for authigenic NH{sub 4}-bearing illite reflect the approximate age of late-stage coalification (formation of anthracite-rank coal) because this mineral formed only during late-stage coalification (T=200-275{degrees}C) from a kaolinite (potassium-free) precursor, and the K/Ar data suggest that NH{sub 4} does not significantly influence the closure temperature of illite. K/Ar dates, in conjunction with paleomagnetic and vitrinite reflectance data, constrain the thermal pulse and deformation associated with the Alleghanian orogenic episode to a time period of 25-35 m.y., beginning in Early Permian time ({approx}285 Ma) after coal deposition, and concluding by Late Permian time ({approx}260-250 Ma). Syn- and post-folding secondary chemical remanent magnetizations constrain Alleghanian folding in the Central Appalachians to Late Permian time, which coincides with the postulated time range of 265-255 Ma for NH{sub 4}-bearing illite authigenesis and anthracite formation derived from the K/Ar data. The similar time range for anthracite formation and Alleghanian folding is consistent with vitrinite reflectance data that suggests anthracite formation was a syn-folding thermal event.

  9. Late Permian age of ammonium-bearing illite in Pennsylvania anthracites: Temporal constraints on coalification in the central Appalachians

    SciTech Connect

    Daniels, E.J. )

    1996-01-01

    K/Ar dating of authigenic NH4-bearing illite in coal from the Anthracite region of eastern Pennsylvania yields apparent ages of 253-236 Ma ([+-]8 m.y.). The oldest K/Ar date of 253 Ma ([+-]8 m.y.) is a minimum age for the thermal event associated with anthracite formation and illite authigenesis. This date is probably within [approx]10 m.y. of the time at which coal-bearing rocks experienced peak temperatures, which suggests an age range of 265-255 Ma for this event. Age dates for authigenic NH[sub 4]-bearing illite reflect the approximate age of late-stage coalification (formation of anthracite-rank coal) because this mineral formed only during late-stage coalification (T=200-275[degrees]C) from a kaolinite (potassium-free) precursor, and the K/Ar data suggest that NH[sub 4] does not significantly influence the closure temperature of illite. K/Ar dates, in conjunction with paleomagnetic and vitrinite reflectance data, constrain the thermal pulse and deformation associated with the Alleghanian orogenic episode to a time period of 25-35 m.y., beginning in Early Permian time ([approx]285 Ma) after coal deposition, and concluding by Late Permian time ([approx]260-250 Ma). Syn- and post-folding secondary chemical remanent magnetizations constrain Alleghanian folding in the Central Appalachians to Late Permian time, which coincides with the postulated time range of 265-255 Ma for NH[sub 4]-bearing illite authigenesis and anthracite formation derived from the K/Ar data. The similar time range for anthracite formation and Alleghanian folding is consistent with vitrinite reflectance data that suggests anthracite formation was a syn-folding thermal event.

  10. Ground-penetrating radar reveals ice thickness and undisturbed englacial layers at Kilimanjaro's Northern Ice Field

    NASA Astrophysics Data System (ADS)

    Bohleber, Pascal; Sold, Leo; Hardy, Douglas R.; Schwikowski, Margit; Klenk, Patrick; Fischer, Andrea; Sirguey, Pascal; Cullen, Nicolas J.; Potocki, Mariusz; Hoffmann, Helene; Mayewski, Paul

    2017-02-01

    Although its Holocene glacier history is still subject to debate, the ongoing iconic decline of Kilimanjaro's largest remaining ice body, the Northern Ice Field (NIF), has been documented extensively based on surface and photogrammetric measurements. The study presented here adds, for the first time, ground-penetrating radar (GPR) data at centre frequencies of 100 and 200 MHz to investigate bed topography, ice thickness and internal stratigraphy at NIF. The direct comparison of the GPR signal to the visible glacier stratigraphy at NIF's vertical walls is used to validate ice thickness and reveals that the major internal reflections seen by GPR can be associated with dust layers. Internal reflections can be traced consistently within our 200 MHz profiles, indicating an uninterrupted, spatially coherent internal layering within NIF's central flat area. We show that, at least for the upper 30 m, it is possible to follow isochrone layers between two former NIF ice core drilling sites and a sampling site on NIF's vertical wall. As a result, these isochrone layers provide constraints for future attempts at linking age-depth information obtained from multiple locations at NIF. The GPR profiles reveal an ice thickness ranging between (6.1 ± 0.5) and (53.5 ± 1.0) m. Combining these data with a very high resolution digital elevation model we spatially extrapolate ice thickness and give an estimate of the total ice volume remaining at NIF's southern portion as (12.0 ± 0.3) × 106 m3.

  11. Assessing local instrument reliability and validity: a field-based example from northern Uganda.

    PubMed

    Betancourt, Theresa S; Bass, Judith; Borisova, Ivelina; Neugebauer, Richard; Speelman, Liesbeth; Onyango, Grace; Bolton, Paul

    2009-08-01

    This paper presents an approach for evaluating the reliability and validity of mental health measures in non-Western field settings. We describe this approach using the example of our development of the Acholi psychosocial assessment instrument (APAI), which is designed to assess depression-like (two tam, par and kumu), anxiety-like (ma lwor) and conduct problems (kwo maraco) among war-affected adolescents in northern Uganda. To examine the criterion validity of this measure in the absence of a traditional gold standard, we derived local syndrome terms from qualitative data and used self reports of these syndromes by indigenous people as a reference point for determining caseness. Reliability was examined using standard test-retest and inter-rater methods. Each of the subscale scores for the depression-like syndromes exhibited strong internal reliability ranging from alpha = 0.84-0.87. Internal reliability was good for anxiety (0.70), conduct problems (0.83), and the pro-social attitudes and behaviors (0.70) subscales. Combined inter-rater reliability and test-retest reliability were good for most subscales except for the conduct problem scale and prosocial scales. The pattern of significant mean differences in the corresponding APAI problem scale score between self-reported cases vs. noncases on local syndrome terms was confirmed in the data for all of the three depression-like syndromes, but not for the anxiety-like syndrome ma lwor or the conduct problem kwo maraco.

  12. Assessing local instrument reliability and validity: A field-based example from northern Uganda

    PubMed Central

    Betancourt, Theresa; Bass, Judith; Borisova, Ivelina; Neugebauer, Richard; Speelman, Liesbeth; Onyango, Grace; Bolton, Paul

    2008-01-01

    This paper presents an approach for evaluating the reliability and validity of mental health measures in non-Western field settings. We describe this approach using the example of our development of the Acholi Psychosocial Assessment Instrument (APAI), which is designed to assess depression-like (two tam, par and kumu), anxiety-like (ma lwor) and conduct problems (kwo maraco) among war-affected adolescents in northern Uganda. To examine the criterion validity of this measure in the absence of a traditional gold standard, we derived local syndrome terms from qualitative data and used self reports of these syndromes by indigenous people as a reference point for determining caseness. Reliability was examined using standard test-retest and inter-rater methods. Each of the subscale scores for the depression-like syndromes exhibited strong internal reliability ranging from α =0.84 to 0.87. Internal reliability was good for anxiety (0.70), conduct problems (0.83), and the pro-social attitudes and behaviors (0.70) subscales. Combined inter-rater reliability and test-retest reliability were good for most subscales except for the conduct problem scale and prosocial scales. The pattern of significant mean differences in the corresponding APAI problem scale score between self-reported cases vs. noncases on local syndrome terms was confirmed in the data for all of the three depression-like syndromes, but not for the anxiety-like syndrome ma lwor or the conduct problem kwo maraco. PMID:19165403

  13. Combustion of Anthracite-Bituminous Coal Blends in a Spreader Stoker Boiler at Holston Army Ammunition Plant

    DTIC Science & Technology

    1988-11-01

    also supplying heat to the boiler for rapid load changes . 9 :3 *.. c Is td b o bo~t L.bec c l * 41 j-- 0U ic u to ’Uz in 0. 00. 0 0 cO-~ c v 0 W 04~ m 0...continuity between different boiler operators. Once the desired test steam load was reached in the morning and the ash bed on the grates was established...ferent percentages of anthracite and bituminous in the blend at different operating loads on the boiler . Blends of 15, 22, 30 and 42 percent anthracite

  14. Potential for increased use of anthracite by electric utilities: implications of the exemption from the EPA new source performance standards for power plants

    SciTech Connect

    Not Available

    1982-02-01

    The prospect for expanded utility use of anthracite by the year 2000 appears promising. It has been generally considered that anthracite can meet the ambient SO/sub 2/ standard of 1.2 lbs. SO/sub 2/ per million Btu without the use of scrubbers. In that event, the results of the engineering economic analysis show that an anthracite-based electric generating unit can be competitive with a comparable bituminous coal-fired unit. The logical competitive utility market area for anthracite is the Northeastern United States and the Middle Atlantic States because of the proximity of these areas to the anthracite region. Transport costs would be lower for anthracite (versus western Pennsylvania bituminous coal) to destinations in the areas of states immediately north, east and southeast of the eastern Pennsylvania anthracite region - upstate New York, New Jersey and Delaware, in particular. The analyses of the impact of the New Source Performance Standards (NSPS) exemption, and of future base load plant expansions, indicates that the potential additional utility use of anthracite over the next two decades is within a range of 1.5 to 15 million tons per year. One means of enhancing the competitive posture of anthracite versus bituminous, the analysis concludes, could be a more intense examination of anthracite resources to determine the best locations of large quantities of low sulfur recoverable reserves. Similarly, a more detailed investigation of a stockpile program would be warranted to determine its feasibility as a means of providing reserve potential, primarily during initial expansion, to allay supply reliability concerns.

  15. Polio field census and vaccination of underserved populations--northern Nigeria, 2012-2013.

    PubMed

    2013-08-23

    In 2012, the World Health Assembly declared completion of polio eradication a public health emergency. However, wild poliovirus (WPV) transmission remains endemic in three countries (Afghanistan, Nigeria, and Pakistan). In Nigeria, the National Stop Transmission of Polio (N-STOP) program, under the umbrella of the Nigerian Field Epidemiology and Laboratory Training Program (FELTP), has been developed to implement innovative strategies that address the remaining polio eradication challenges in Nigeria. One N-STOP initiative focuses on locating and vaccinating children aged<5 years in remote nomadic, scattered, and border populations in northern Nigeria, where low polio vaccination coverage likely contributes to ongoing WPV transmission. During August 2012-April 2013, N-STOP conducted field outreach activities that enumerated 40,212 remote settlements, including 4,613 (11.5%) settlements never visited by vaccination teams during previous polio supplemental immunization activities (SIAs). Enumeration resulted in documentation of 906,201 children aged<5 years residing in these settlements, including 53,738 (5.9%) who had never received polio vaccination, and in detection of 211 unreported cases of acute flaccid paralysis (AFP) with onset of illness in the 6 months before enumeration. Sustaining access to underserved populations in remote settlements in future SIAs will increase overall population immunity and should decrease WPV transmission. By providing a flexible and capable workforce consisting of Nigerian citizens, N-STOP is able to support evaluation and implementation of innovative polio eradication strategies in Nigeria while building local public health capacity with a potential to address other public health problems following the eradication of polio from Nigeria.

  16. Structural evolution of the Abu Gharadig field area, Northern Western Desert, Egypt

    NASA Astrophysics Data System (ADS)

    El Gazzar, A. M.; Moustafa, A. R.; Bentham, P.

    2016-12-01

    Discovered in 1969, the Abu Gharadig (AG) Field was the first large hydrocarbon discovery in the Abu Gharadig Basin of the Western Desert of Egypt. Oil production began in 1973, with gas brought into production in 1975. The field produces mainly from upper Cretaceous clastic reservoirs. The AG Basin is an E-W trending intracratonic rift basin, about 330 km long and 50-75 km wide. It was initially formed as a large half graben basin during the Jurassic time in response to Tethyan rifting and continued to subside throughout the Cretaceous time. The half graben was subsequently inverted during the Late Cretaceous as part of the Syrian Arc deformation which affected northern Egypt. The Mid-Basin Arch, the AG Anticline, and the Mubarak High are three NE-SW oriented main inversion anticlines located within the AG Basin and are controlled by inversion of pre-existing Jurassic rift faults. The AG Anticline has an overall NE-SW orientation with a gentle plunge towards the NE and SW. It is locally bounded by two NE-SW-trending inverted faults on the southwest and northeast, accounting for the asymmetry of the anticline. Reverse offset of Cretaceous horizons is obvious at these inverted faults. Fault propagation folding is developed above the tips of the inverted faults at the Late Cretaceous Abu Roash and Khoman Formations. Based on thickness changes and stratigraphic relationships, inversion started during the Santonian time and continued into the Campanian-Maastrichtian. Inversion continued during deposition of the Paleocene-Middle Eocene Apollonia Formation and the Late Eocene-Oligocene Dabaa Formation.

  17. On-going post-glacial reverse faulting in Scandinavia, field evidence from Finnmark, northern Norway

    NASA Astrophysics Data System (ADS)

    Pascal, C.; Gabrielsen, R. H.; Cloetingh, S.

    2003-04-01

    Deglaciation in Scandinavia was followed by a dramatic seismic burst as evidenced by the numerous post-glacial fault scarps documented in Lapland. The post-glacial faults usually show reverse slip and trend NE-SW. This climax of earthquake activity is believed to have been triggered by the sudden removal of the glacial load and Scandinavia is considered tectonically quiet present-day. Roberts (1991, 2000) observed in Finnmark, northern Norway, various boreholes offset by reverse faults with few cm of displacement. It was unclear if these reverse faults represented active faulting or stress-relief features. Following Roberts, a field work campaign was conducted in July 2002. The purpose was to examine boreholes along road-sections and in quarries of Finnmark. About 20 drill-hole reverse offsets ranging from a few mm up to 14 cm were measured in western and central Finnmark. The azimuth of the associated slip vectors was found to be consistent towards the E-SE. In the Ifjord area, central Finnmark, some of the fault planes offsetting boreholes show continuous mud-smears of ~10 cm long. In the same area, additional observations include two reverse faults with 2 cm of offset each. The first one disrupts a wall road worked out in 1986. The second reverse fault disrupts a natural scarp presumably of glacial origin. In direct connection with these observations numerous rock blocks are seen to disrupt the ground surface. The most impressive ones are more than 1 m high. The blocks are bounded by pre-existing fractures and cleavage and appear to be displaced to the SE as well. These "standing-stones" are interpreted as small-scale tectonic push-ups. Field observations argue for active reverse faulting in Finnmark. The documented fault motions agree with a regional NW-SE compression induced by the North Atlantic ridge-push.

  18. Geologic field-trip guide to Mount Shasta Volcano, northern California

    USGS Publications Warehouse

    Christiansen, Robert L.; Calvert, Andrew T.; Grove, Timothy L.

    2017-08-18

    off, in a field of high-alumina olivine tholeiite lavas (HAOTs, referred to elsewhere in this guide as low-potassium olivine tholeiites, LKOTs). It proceeds around the southern, western, and northern flanks of Mount Shasta and onto a part of the arc axis. The stops feature elements of the Mount Shasta area in an approximately chronological order, from oldest to youngest.

  19. Field evaluations of the efficacy of Distance Plus on invasive ant species in northern Australia.

    PubMed

    Webb, Garry A; Hoffmann, Benjamin D

    2013-08-01

    The efficacy of Distance Plus Ant Bait, containing the insect growth regulator pyriproxyfen, was tested in the field against two invasive ant species in northern Australia: African big-headed ant (Pheidole megacephala (F.)) and yellow crazy ant (Anoplolepis gracilipes (Fr. Smith)). Results were also gained for a third pest species, Singapore ant (Monomorium destructor (Jerdon)), from one trial focused primarily on P. megacephala. Five studies were conducted throughout northern Australia, each with different protocols, but common to all was the broad-scale dispersal of Distance Plus, coupled with long-term monitoring of ant population levels. Additionally, a laboratory trial was conducted to assess if there was a direct toxic effect by the bait on A. gracilipes workers, and ant community data were collected at some sites in the A. gracilipes trial to assess nontarget impacts and subsequent ecological recovery. All three species were greatly affected by the treatments. The abundance of P. megacephala declined dramatically in all trials, and by the final assessment for each study, very few ants remained, with those remaining being attributable to edge effects from neighboring untreated properties. At both sites that it occurred, M. destructor was initially at least codominant with P. megacephala, but by the final assessment, only three M. destructor individuals were present at one lure at one site, and only a single individual at the other site. Abundance of A. gracilipes fell, on average, to 31% of control levels by 91 d and then slowly recovered, with subsequent treatments only providing slightly greater control. No direct toxic effect on workers was found in the laboratory trial, indicating that population declines of A. gracilipes were typical bait-related declines resulting from reduced worker replacement. Nontarget impacts of the bait could not be distinguished from the negative competitive impacts ofA. gracilipes, but there was a noticeable absence of some key

  20. Ever-shifting ground: work and labor relations in the anthracite coal industry, 1968-1903

    SciTech Connect

    Blatz, P.K.

    1987-01-01

    This dissertation traces the work experience of the mine workers of the anthracite coal industry of northeastern Pennsylvania from the final three decades of the nineteenth century, during which several attempts to unionize the mines failed, to the industry-wide anthracite strikes of 1900 and 1902, which brought to a successful conclusion the United Mine Workers' drive for unionization. The correspondence of corporate executives shows that a pervasive philosophy of antiunionism characterized management's approach to labor relations. During the nonunion era, the state, rather than any labor organization, served as the most effective counterpoise to corporate power through its enactment of an extensive code of mining regulation. Nevertheless, mine workers still confronted a perilous workplace which, along with chronic underemployment and an utterly unsystematized congeries of work rules, combined to create a work experience fraught with insecurity. The United Mine Workers proposed an industry-wide contract as the means to solve these problems, and effective organization as the prod to force the corporations to negotiate such a contract. However, the union succeeded in its organizing only in the wake of numerous wildcat strikes protesting the many manifestations of the paternalistic, individualized style of labor relations which had always characterized the industry.

  1. Effect of Rabi splitting on the low-temperature electron paramagnetic resonance signal of anthracite

    NASA Astrophysics Data System (ADS)

    Fedaruk, Ryhor; Strzelczyk, Roman; Tadyszak, Krzysztof; Markevich, Siarhei A.; Augustyniak-Jabłokow, Maria Aldona

    2017-01-01

    Specific distortions of the EPR signal of bulk anthracite are observed at low temperatures. They are accompanied by variations in the microwave oscillator frequency and are explained by the manifestation of the Rabi splitting due to the strong coupling between electron spins and the cavity, combined with the use of an automatic frequency-control (AFC) system. EPR signals are recorded at negligible saturation in the temperature range of 4-300 K with use of the AFC system to keep the oscillator frequency locked to the resonant frequency of the TM110 cylinder cavity loaded with the sample. For the sample with a mass of 3.6 mg the line distortions are observed below 50 K and increase with temperature lowering. The oscillator frequency variations are used to estimate the coupling strength as well as the number of spins in the sample. It is shown that the spin-cavity coupling strength is inversely proportional to temperature and can be used for the absolute determination of the number of spins in a sample. Our results indicate that at low temperatures even 1016 spins of the anthracite sample, with a mass of about 0.5 mg, can distort the EPR line.

  2. The Northern Plains MSATT Meeting, and a call for a field-oriented successor to MSATT

    NASA Technical Reports Server (NTRS)

    Kargel, J. S.

    1993-01-01

    The workshop was devoted to a review of our knowledge of the Martian northern plains and presentation of recent ideas pertaining to the geologic and climatic evolution of this interesting region. The meeting was held in Fairbanks to allow easy access to Mars-like terrains in central and northern Alaska. There is no place on Earth that is a close analog of the Martian northern plains, but parts of Alaska come reasonably close in some respects, so we may expect that some of the processes occurring there are similar to processes that have occurred on Mars.

  3. A decomposition of northern polar external magnetic fields using the method of Empirical Orthogonal Functions

    NASA Astrophysics Data System (ADS)

    Shore, Robert; Freeman, Mervyn; Wild, James; Dorrian, Gareth; Gjerloev, Jesper

    2015-04-01

    We describe our application of the Empirical Orthogonal Function (EOF) method to characterise and separate contributions to the variability of the Earth's external magnetic field (EMF), using ground magnetometer measurements. The method (commonly employed in meteorology) analyses the spatio-temporal co-variance of the data to decompose it into dynamically distinct 'modes'. A small number of these modes can cumulatively represent most of the variance of the original data, with the additional aim that a physical meaning can be given to each mode. Since the basis vectors of the decomposition are defined by the data, the EOF method resolves the spatial and temporal structure of the EMF without a priori assumptions, in contrast to other decomposition methods such as Fourier and spherical harmonic expansions. We present the results from a case study focusing on northern high latitudes throughout February 2001, using data from 97 observatories and 78 variometers collated by SuperMAG. We have devised a new baseline in order to make the observatory and variometer data comparable, and subsequently binned the data in an inertial frame. Despite the sparse and irregular station distribution, a complete spatial morphology of the EMF is achieved using a self-consistent iterative infill method. The majority (67%) of the variance in our case-study is described by the first four modes. From the spatial morphology and a comparison of the temporal behaviour of these four modes alongside independent measures, we demonstrate that the leading two modes define the well-known DP2 (Disturbance-Polar 2) and DP1 (Disturbance-Polar 1) current systems, and the other two modes describe the spatial motion of the DP1 and DP2 systems. This practical demonstration is a prelude to producing a model of EMF variations over a whole solar cycle using the full SuperMAG archive from 1996 to 2008.

  4. Free phase gas processes in a northern peatland inferred from autonomous field-scale resistivity imaging

    NASA Astrophysics Data System (ADS)

    Terry, Neil; Slater, Lee; Comas, Xavier; Reeve, Andrew S.; Schäfer, Karina V. R.; Yu, Zhongjie

    2016-04-01

    The mechanisms that control free phase gas (FPG) dynamics within peatlands, and therefore estimates of past, present, and future gas fluxes to the atmosphere remain unclear. Electrical resistivity imaging (ERI) is capable of autonomously collecting three-dimensional data on the centimeter to tens of meter scale and thus provides a unique opportunity to observe FPG dynamics in situ. We collected 127 3-D ERI data sets as well as water level, soil temperature, atmospheric pressure, and limited methane flux data at a site in a northern peatland over the period July-August 2013 to improve the understanding of mechanisms controlling gas releases at a hitherto uncaptured field scale. Our results show the ability of ERI to image the spatial distribution of gas accumulation and infer dynamics of gas migration through the peat column at high (i.e., hourly) temporal resolution. Furthermore, the method provides insights into the role of certain mechanisms previously associated with the triggering of FPG releases such as drops in atmospheric pressure. During these events, buoyancy-driven gas release primarily occurs in shallow peat as proposed by the "shallow peat model." Releases from the deeper peat are impeded by confining layers, and we observed a large loss of FPG in deep peat that may likely represent a rupture event, where accumulated FPG escaped the confining layer as suggested by the "deep peat model." Negative linear correlations between water table elevation and resistivity result from hydrostatic pressure regulating bubble volume, although these variations did not appear to trigger FPG transfer or release.

  5. Prototype anthracite culm combustion boiler/heater unit. Quarterly technical report No. 4, July 1-September 30, 1979

    SciTech Connect

    Not Available

    1980-01-01

    There are currently about 910 million cubic yards of anthracite culm (mine refuse) contained in 800 separate banks in a 480 square mile area in the Wilkes-Barre (W-B) anthracite mining region. Although this material represents a significant fuel value, equivalent to approximately 1.25 billion barrels of fuel oil, the culm banks have accumulated because no satisfactory method of combusting this fuel was available until the relatively recent development of the atmospheric fluidized bed (AFB) steam generator. A program was initiated in October 1978 to design, construct and evaluate a 100,000 pph AFB steam generator burning anthracite culm with the addition of fresh anthracite, if required. The unit is to demonstrate the technical, economical and environmental feasibility of producing 150 psig saturated steam for district heating in downtown W-B. Phase I of the program consists of the design of the atmospheric fluidized bed (AFB) plant and a hot model test program. Phase II of the program consists of construction, operation, testing and evaluation of the boiler and boiler plant.

  6. 77 FR 27108 - Order of Suspension of Trading; In the Matter of Anthracite Capital, Inc., Auto Data Network Inc...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-08

    ... From the Federal Register Online via the Government Publishing Office ] SECURITIES AND EXCHANGE COMMISSION Order of Suspension of Trading; In the Matter of Anthracite Capital, Inc., Auto Data Network Inc., Avenue Group, Inc., Ckrush, Inc., Clickable Enterprises, Inc., and DCI USA, Inc. May 4, 2012 It appears to the Securities and...

  7. Seismic network detection capability within the natural gas fields in Northern Germany

    NASA Astrophysics Data System (ADS)

    Gestermann, Nicolai; Plenefisch, Thomas

    2016-04-01

    The Northern German basin is a tectonic region of relatively low seismic activity with only singular and weak tectonic events. However, during the last decades seismicity raised in the vicinity of the natural gas fields. Due to the spatial vicinity of the epicenters to the operated gas fields and their appearance starting after the beginning of extraction they are ranked as induced events. The epicenters of these events extend 50 km NS and 400 km EW from the border to the Netherlands in the West to Altmark region in the East. Altogether, 63 events with ML 0.5 to 4.5 were detected between 1977 and 2015. Many of them were felt by parts of the inhabitants up to 15 km from the epicenter whereas the strongest one, the magnitude 4.5 event close to the village of Rotenburg on 20th October 2004, was even felt in Hamburg as far as 65 km from the epicenter. Several new installed surface and borehole stations have recently improved the monitoring capabilities in the region. The station network design and number of station varied significantly during the last years and only a few seismic stations were operational over the entire period. This variability was not taken into account for the assessment of the seismicity like the b-value and completeness. For some of the areas it is still difficult to detect and analyze events with magnitude below 2 due to bad noise conditions invoked by the thick sediments as well as to the relatively large area to be covered. Up to now, it is not clear whether the small number of fore- and aftershocks is an inherent characteristic of the induced events and thereby different from tectonic earthquake sequences or only the effect of the non appropriate seismic surveillance during the last decades. Seismicity in a low magnitude range could not be detected in some of the areas but should exist if the Gutenberg-Richter relation is valid. The detection capability can be one of the reasons and is now estimated for the main active areas as a function of

  8. Structure of the coastal current field off northern California during the Coastal Ocean Dynamics Experiment

    NASA Astrophysics Data System (ADS)

    Kosro, P. Michael

    1987-02-01

    For 74 days during the spring and summer upwelling seasons of 1981 and 1982, in conjunction with the Coastal Ocean Dynamics Experiment, profiles of upper ocean currents were collected in the waters over the shelf and slope off northern California using a shipboard Doppler acoustic log. These measurements provide detailed information on the spatial structure of the current field. Synoptic maps of near-surface currents often deviate substantially from classical two-dimensional wind-driven upwelling and indicate a close association between the complex temperature structures observed in satellite imagery and the presence of vigorous current structures including squirts (regions of intense seaward flow), eddies, and countercurrents. Well-defined examples of a squirt and of a countercurrent during a cessation of wind forcing (wind relaxation event) are examined in detail. Despite this complexity, the nearshore synoptic current field was found to be anisotropic, varying more rapidly cross shore than alongshore. The structure of the current averages and simple fluctuation statistics were largely as deduced in other upwelling areas from moored measurements. A surface-intensified equatorward jet was found in the average alongshore currents, with vertical shear exceeding -2 × 10-3 s-1 over much of the shelf. The core of the jet moved offshore south of Point Arena and was better resolved in along-isobath averages. At depths below 80 m the average alongshore flow reversed, giving way to a poleward undercurrent, strongest near the shelf break. The detailed structure of the inferred cross-shore circulation was found to be sensitive to the coordinate system selected. Using nominal (along-coast) coordinates, the average cross-shore current was found to be directed offshore within a surface layer which deepened with distance from the coast out to the shelf break, showed strong vertical shear only near the surface, and was divergent in the upper water column and convergent in the

  9. Ice volume assessment of the Northern Ice Field of Kilimanjaro: the photogrammetry strikes back

    NASA Astrophysics Data System (ADS)

    Sirguey, P. J.; Cullen, N. J.; Moelg, T.; Kaser, G.

    2013-12-01

    Glaciers in tropical regions have retreated drastically since the mid and second half of the 19th century, with glaciers on Africa's highest mountain, Kilimanjaro, being no exception to this trend. The demise of glaciers on Kibo has been documented for about 130 years based on multiple mapping techniques ranging from ground based photogrammetry to satellite imaging. In this context, a consistent time series of glacier retreat on Kilimanjaro over the last century was recently compiled that permitted the areal rate of retreat of ice over the last decade to be characterized. However, while margin and areal retreat of Kilimanjaro glaciers have been measured on numerous occasions, assessments of ice volume and thinning rate have received far less attention. This study reports on the creation of a 1-m resolution Digital Surface Model (DSM) of Kilimanjaro via photogrammetry of GeoEye-1 imagery. Twenty Ground Control Points (GCP) surveyed between 20 and 26 September 2012 were used to triangulate four GeoEye panchromatic stereo pairs (50cm resolution) acquired between 20 September and 23 October 2012. Multi-ray processing of multiple combinations of image overlaps permitted a dense point cloud to be produced that supported the creation of the very high resolution DSM. The model was assessed independently by means of a leave-one-out cross validation protocol, yielding a RMS error of 0.45, 0.67, and 1.19m on x, y, and z, respectively. A Digital Terrain Model (DTM) of the Northern Ice Field (NIF) could be produced that allowed the total volume of the ice remnants to be estimated. Finally, the new DSM was compared with the SRTM DEM of February 2000. The difference between both surfaces permitted the volume lost by the NIF over 12.7 years to be estimated, as well as spatial pattern of the thinning to be revealed. The new DSM revealed an unprecedented amount of detail of the NIF that split earlier into the remnants of the Credner glacier (C) to the North and that of Drygalsky and

  10. Community-Provider Partnerships to Reduce Immunization Disparities: Field Report From Northern Manhattan

    PubMed Central

    Findley, Sally E.; Irigoyen, Matilde; See, Donna; Sanchez, Martha; Chen, Shaofu; Sternfels, Pamela; Caesar, Arturo

    2003-01-01

    In 1996 we launched a community–provider partnership to raise immunization coverage for children aged younger than 3 years in Northern Manhattan, New York City. The partnership was aimed at fostering provider knowledge and accountability, practice improvements, and community outreach. By 1999 the partnership included 26 practices and 20 community groups. Between 1996 and 1999, immunization coverage rates increased in Northern Manhattan 5 times faster than in New York City and 8 times faster than in the United States (respectively, 3.4% vs 0.4% [t = 6.05, p < 0.001] and vs 0.6% [t = 5.65, p < 0.001]). The coverage rate for Northern Manhattan stayed constant through 2000, although it declined during this period for the United States and New York City. We attribute the success at reducing the gap to the effectiveness of our partnership. PMID:12835176

  11. HF radar observations in the northern Adriatic: surface current field in front of the Venetian Lagoon

    NASA Astrophysics Data System (ADS)

    Kovačević, V.; Gačić, M.; Mancero Mosquera, I.; Mazzoldi, A.; Marinetti, S.

    2004-11-01

    Two HF radar stations looking seaward were installed along the littoral of the Venetian Lagoon (Northern Adriatic). They operated continuously for 1 year (November 2001-October 2002). The surface current data are obtained at a spatial resolution of about 750 m and are available every hour in a zone whose depths slope gently from the coast down to 20 m. The total area covered is about 120 km 2 reaching cca 15 km offshore. These observations give evidence of the different temporal and spatial scales that characterize the current field. Unlike for the flow in inlets of the Venetian Lagoon, the tidal forcing accounts for only up to 20% of the total variability. The tidal influence from the inlets is felt to about 4-5 km away. Low-frequency signal, associated prevalently to meteorological forcing (through the action of winds and atmospheric pressure) at synoptic time scales, is superimposed on a mean southward flow of 10 cm/s. Formation of small-scale eddies (diameter of about 5 km) to the north and to the south of the Malamocco inlet is observed only during the periods of calm. During strong northeasterly bora and southeasterly sirocco winds, an increase of the along-shore southward current due to geostrophic adjustment is observed in a coastal band. A particularly strong bora event in December 2001 generated an almost uniform flow reaching 30-50 cm/s in the whole investigated area. During sirocco in June 2002, a current reversal toward north and a triggering of inertial motions were observed. Yearlong measurements give an insight into a seasonal variability through a sequence of mean monthly current maps. In November and December, the intensity was the highest (up to 18 cm/s), and the flow structure was almost uniform, with a weak shear in the offshore direction. The weakest mean flow was observed in May 2002, characterized however with a nonuniform distribution over the study zone and suggestions of anticyclonic eddies north and south of the Malamocco inlet. On the

  12. Magnetic Field Modeling of the Northern Juan De Fuca and Explorer Plates

    DTIC Science & Technology

    1993-07-01

    THE i NORTHERN JUAN DE FUCA AND EXPLORER PLATES I I JOHN M. QUINN DONALD L. SHIEL DTIC "ELECTE 1AU 18 1994U s.I GD SI q •-(494-26093I...concerns a low-level Project MAGNET survey of the northern Juan de Fuca and Explorer Plates , a region of intense scientific interest due to its volcanic...Juan de Fuca and Explorer Plates 5. AUTHOR(S) John H. Quinn Donald L. Shiel 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING

  13. The effect of molten caustic leaching on a structure of anthracite

    SciTech Connect

    Lee, S.H.; Shon, E.K.; Park, S.H.

    1995-12-31

    Korean anthracite and imported bituminous coal were treated according to the molten caustic leaching (MCL) process and the changes in their organic structure and combustion characteristics sere investigated. This investigation was conducted through functional group analysis, vitrinite reflectance measurements, maceral and TGA analysis. Results of analysis showed that the highly reactive aliphatic hydrocarbons linked with aromatic rings decreased and the vitrinite reflectance increased after treatment. These are changes observed when carbonization occurred. However, the results of observation of maceral surfaces showed that the surface of the organic groups were severely collapsed and the anisotropy, which should increase with carbonization, decreased. It was found that the changes in the combustion temperature and the reactivity after treatment with MCL were attributed to the physical changes on the surface of organic groups rather than to the chemical changes such as break down in the organic groups.

  14. Rehabilitation of an anthracite-burning power plant in Ukraine with introduction of coal preparation

    SciTech Connect

    Ruether, J.; Killmeyer, R.; Schimmoller, B.; Gollakota, S.

    1996-12-31

    A study is being carried out jointly by the United States Department of Energy and the Ukrainian Ministry of Power and Electrification for rehabilitation of an anthracite-burning power station in the Donbass region of eastern Ukraine. The power station, named Luganskaya GRES, is laboring under deteriorating coal quality (the ash level is ranging towards 40% compared to the design value of 18%) and the physical plant is in need of repair. Approaches under consideration for the rehabilitation include upgrading the existing 200-MW{sub e} (gross) wall-fired boilers, repowering with circulating fluidized bed combustors, and the use of coal preparation. Coal washability tests conducted as part of the study indicate the coal is amenable to washing. The paper describes approaches to coal preparation being considered that provide design value coal for wall-fired boilers while minimizing rejection of Btus and generation of solid waste.

  15. Indication of meta-anthracite by magnetotellurics in the Köszeg-Rechnitz Penninic window

    NASA Astrophysics Data System (ADS)

    Novák, Attila; Ádám, Antal; Prácser, Ernő

    2013-04-01

    In the Eastern end of the Eastern Alps - at the Austrian-Hungarian border - there are Pennninic Nappes among them the Köszeg-Rechnitz tectonic window having complicated metamorphic history from the Jurassic time. The organic material of the Penninic Ocean transformed to meta-anthracite. Its amount in the calc-phyllite has been estimated by the geochemists to 0.2 percent. Magnetotelluric soundings have been carried out to determine: - the resistivity decrease due to the above amount of conductive material, - the different EM distortions in E and B polarization caused by the conductor near and far from it, - the asthenospheric depth in the area of the tectonic window stepping out from the shallow asthenosphere of the Pannonian Basin, - looking for relation between geoelectric and seismic crustal structures.

  16. Field Performance of High-Quality and Standard Northern Red Oak Seedlings in Tennessee

    Treesearch

    David S. Buckley

    2002-01-01

    First-year performance of high-quality (HQ), high-quality cull (HQC) and standard (ST) northern red oak (Quercus rubra) nursery seedlings was compared in a study established in a recent clearcut in mid-March, 2000. Objectives were to test effects of 1) seedling type, 2) planting treatment, and 3) control of competitors on the growth, browsing, and...

  17. Predation by northern pikeminnow on juvenile salmonids in The Dalles Dam tailrace: field, laboratory, and habitat modeling studies (FY2000)

    USGS Publications Warehouse

    Petersen, James H.; Barfoot, Craig A.; Sheer, Mindi B.

    2001-01-01

    Predation by resident fish is known to be a substantial cause of juvenile salmonid mortality, especially in dam tailraces and outfall locations. Conditions in The Dalles Dam tailrace are unique compared to other projects on the Columbia or Snake rivers, having a complex basin with a series of downriver islands where predators are known to reside. In May-June of 1999, northern pikeminnow and smallmouth bass were sampled in the tailrace of The Dalles Dam during periods immediately following the release of PIT-tagged juvenile salmonids for survival studies. Over twice as many smallmouth bass (N = 101) were collected as northern pikeminnow (N = 40), but none of the predators had PIT tags within their gut. A laboratory study was conducted to estimate the time required for PIT tags in juvenile salmonids to be evacuated from the gut of northern pikeminnow after consuming a tagged preyfish. Evacuation rate was sensitive to temperature, with median evacuation time being 21 h at 18 oC and 30 h at 14 oC. These results suggest that field studies to estimate predator population sizes, feeding rates, or predation on specific release groups would require considerably more effort than we allocated during 1999.

  18. Late Permian age of NH[sub 4]-bearing illite in anthracite from eastern Pennsylvania. Temporal limits on coalification in the central Appalachians

    SciTech Connect

    Daniels, E.J.; Altaner, S.P. ); Aronson, J.L. ); Clauer, N. )

    1994-06-01

    Authigenic NH[sub 4]-bearing illites in coal fractures from the Anthracite region of eastern Pennsylvania yield individual K/Ar dates of 236-253 Ma ([+-]8 m.y.) and a composite isochron of 253 Ma ([+-]8 m.y.). Rh/Sr data for the same samples indicate an isochron of 260 Ma ([+-]44 m.y.), consistent with the more precise K/Ar data. The age of NH[sub 4]-bearing illite authigenesis should reflect the time at which coal attained anthracite rank, because mineralogical and geochemical evidence indicates that NH[sub 4]-bearing illite formed exclusively during anthracite formation (T = 200-275[degree]C) from organically derived nitrogen and a kaolinite precursor. Similar Late Permian K/Ar dates for both NH[sub 4]-rich illite and K-illite in anthracite fractures and lack of correlation between percent NH[sub 4] substitution in illite and the K/Ar date suggest that NH[sub 4] does not influence significantly the closure temperature of illite and, thus, that NH[sub 4]-rich illite can be used for dating the time of authigenesis. Given the uncertainties in closure temperatures for illite as well as the maximum temperatures for anthracite formation, we consider the oldest K/Ar date of 253 Ma ([+-]8 m.y.) to be a minimum age for NH[sub 4]-illite authigenesis and anthracite formation. 33 refs., 4 figs., 4 tabs.

  19. Evaluation of co-cokes from bituminous coal with vacuum resid or decant oil, and evaluation of anthracites, as precursors to graphite

    NASA Astrophysics Data System (ADS)

    Nyathi, Mhlwazi S.

    2011-12-01

    Graphite is utilized as a neutron moderator and structural component in some nuclear reactor designs. During the reactor operaction the structure of graphite is damaged by collision with fast neutrons. Graphite's resistance to this damage determines its lifetime in the reactor. On neutron irradiation, isotropic or near-isotropic graphite experiences less structural damage than anisotropic graphite. The degree of anisotropy in a graphite artifact is dependent on the structure of its precursor coke. Currently, there exist concerns over a short supply of traditional precursor coke, primarily due to a steadily increasing price of petroleum. The main goal of this study was to study the anisotropic and isotropic properties of graphitized co-cokes and anthracites as a way of investigating the possibility of synthesizing isotropic or near-isotropic graphite from co-cokes and anthracites. Demonstrating the ability to form isotropic or near-isotropic graphite would mean that co-cokes and anthracites have a potential use as filler material in the synthesis of nuclear graphite. The approach used to control the co-coke structure was to vary the reaction conditions. Co-cokes were produced by coking 4:1 blends of vacuum resid/coal and decant oil/coal at temperatures of 465 and 500 °C for reaction times of 12 and 18 hours under autogenous pressure. Co-cokes obtained were calcined at 1420 °C and graphitized at 3000 °C for 24 hours. Optical microscopy, X-ray diffraction, temperature-programmed oxidation and Raman spectroscopy were used to characterize the products. It was found that higher reaction temperature (500 °C) or shorter reaction time (12 hours) leads to an increase in co-coke structural disorder and an increase in the amount of mosaic carbon at the expense of textural components that are necessary for the formation of anisotropic structure, namely, domains and flow domains. Characterization of graphitized co-cokes showed that the quality, as expressed by the degree of

  20. Laser-induced breakdown spectroscopy for determination of the organic oxygen content in anthracite coal under atmospheric conditions.

    PubMed

    Zhang, Lei; Dong, Lei; Dou, Haipeng; Yin, Wangbao; Jia, Suotang

    2008-04-01

    Laser-induced breakdown spectroscopy has been used to measure the organic oxygen content in pulverized anthracite coal under atmospheric conditions. Special spectral processing including the optimal O(I) emission-line selection by comparing the spectral correlation coefficients with the N(I) line, internal normalization with the N(I) line, and temperature correction are proposed and employed to satisfy the multi-line analysis method and yield the most accurate quantitative results. The calibration method for determining the organic oxygen content of coal is presented, with an accuracy of 1.15-1.37% and an average relative error of 19.39% being evaluated through an experiment performed on six anthracite coal samples. The relative measurement error distribution has also been studied.

  1. Laser-induced breakdown spectroscopy for determination of the organic oxygen content in anthracite coal under atmospheric conditions

    SciTech Connect

    Zhang, L.; Dong, L.; Dou, H.P.; Yin, W.B.; Jia, S.T.

    2008-04-15

    Laser-induced breakdown spectroscopy has been used to measure the organic oxygen content in pulverized anthracite coal under atmospheric conditions. Special spectral processing including the optimal O(I) emission-line selection by comparing the spectral correlation coefficients with the N(I) line, internal normalization with the N(I) line, and temperature correction are proposed and employed to satisfy the multi-line analysis method and yield the most accurate quantitative results. The calibration method for determining the organic oxygen content of coal is presented, with an accuracy of 1.15-1.37% and an average relative error of 19.39% being evaluated through an experiment performed on six anthracite coal samples. The relative measurement error distribution has also been studied.

  2. Evidence for the correlation of the upper part of the Llewellyn Formation (Pennsylvania Anthracite region), with the Monongahela Formation

    USGS Publications Warehouse

    Eggleston, J.R.; Wnuk, C.; Edmunds, W.E.

    1996-01-01

    A plant fossil assemblage from the roof shale of the No. 25 anthracite bed in Pennsylvania indicates that the upper part of the Llewellyn Formation is much younger than the lower part of the Allegheny Group or Conemaugh Group correlation that was indicated by Read and Mamay (1960). These results confirm the conclusions of Fontaine and White (1880), White (1900), and Darrah (1969) who suggested that the highest coals of the Llewellyn Formation could be equivalent to the Monongahela Group.

  3. Combustion of high-sulfur coal and anthracite wastes in a rotary kiln combustor with an advanced internal air distributor

    SciTech Connect

    Cobb, J.T. Jr. ); Ahn, Y.K. ); Angelo, J.F. )

    1990-01-01

    Fluid bed combustors have received extensive testing with both high-sulfur coal and anthracite wastes. Rotary kilns are effective and popular devices for waste combustion. The Angelo Rotary Furnace{trademark} has been developed to improve the operation of rotary pyrolyzer/combustor systems through enhanced air distribution, which in this process is defined as staged, swirled combustion air injection. Fourteen of these new furnaces have been installed worldwide. Two units in Thailand, designed for rice hull feed with occasional lignite feed, have been recently started up. An older unit in Pennsylvania is being upgraded with a new, more advanced air distribution system for a series of tests this fall in which inexpensive high-sulfur coal and anthracite wastes will be fired with limestone. The purposes of these tests are to determine the burning characteristics of these two fuels in this system, to discover the Ca/S ratios necessary for operation of a rotary kiln combusting these fuels, and to observe the gas-borne emissions from the furnace. An extensive preliminary design study will be performed on a commercial installation for combustion of anthracite wastes. 14 refs., 5 figs., 1 tab.

  4. The safety and economics of high ash anthracite fired mixing with petroleum-coke in pulverized coal-fired furnace

    SciTech Connect

    Zhang, Z.; Sun, X.; Li, F.

    1996-12-31

    Petroleum-coke was fired only in CFB because of its content of high S and low volatile matter. It will bring environmental and flame stability problems if petroleum-coke is fired in a pulverized coal-fired furnace. Low rank anthracite is fired in many pulverized coal-fired furnaces without flame stability problems. Here the authors blend high ash anthracite with petroleum-coke as the fuel for a pulverized coal-fired furnace to decrease the ash content in the fuel. Experimental results had shown that in mixing with petroleum-coke, the combustion behavior of the blended fuel was improved and ash deposition characteristic would not change compared with high ash anthracite. Using coal/petroleum-coke as the fuel for furnace can bring great benefits for the environment and furnace. But S content in blended fuel must be controlled under the regulation of S content in coal and the volatile content should not decrease too low for the coal-fired furnace design to avoid the environmental and flame stability problems.

  5. Magnetospheric period magnetic field oscillations at Saturn: Equatorial phase “jitter” produced by superposition of southern and northern period oscillations

    NASA Astrophysics Data System (ADS)

    Provan, G.; Andrews, D. J.; Cecconi, B.; Cowley, S. W. H.; Dougherty, M. K.; Lamy, L.; Zarka, P. M.

    2011-04-01

    We investigate magnetic field oscillations near the planetary rotation period in Saturn's magnetosphere observed during the initial near-equatorial phase of the Cassini mission. Phase determinations on 28 periapsis passes during this ˜2 year interval display pronounced nonrandom “jitter” relative to the ˜10.8 h modulations in the dominant southern Saturn kilometric radiation (SKR) emissions. Phase deviations in the radial and azimuthal components are strongly positively correlated, while being anticorrelated with the phase deviations in the colatitudinal component. This suggests the presence in the equatorial magnetosphere of superposed weaker field oscillations at the ˜10.6 h period of the northern SKR modulations, the phase deviations being shown to be periodic near the corresponding ˜23 day “beat” period. Modeling the effect of the northern period oscillations shows that their amplitude is ˜30%-40% of the southern period oscillations, producing phase deviations of ˜±25°. The relative phasing of the northern period radial and azimuthal fields is such as to form a rotating quasi-uniform field, as for the southern period oscillations, while the phasing of the colatitudinal component indicates perturbation field lines arched with apices pointing to the south, opposite to the southern period field lines that are arched with apices pointing to the north. The northern period field points sunward at northern SKR maxima, consistent with previous observations of the northern polar oscillations and opposite to the southern period field that points tailward at southern SKR maxima. The results support the view that the field oscillations are due to two auroral current systems that rotate with differing periods in the two hemispheres.

  6. 2-D Fourier transform analysis of the gravitational field of Northern Sinai Peninsula

    NASA Astrophysics Data System (ADS)

    Khalil, Mohamed A.; Santos, Fernando M.; Farzamian, Mohammad; El-Kenawy, Abeer

    2015-04-01

    The Sinai Peninsula has fascinated the consideration of many geophysical studies as it is influenced by major tectonic events. Those are (1) the Mesozoic to Early Cenozoic tectonically active opening of Tethys, (2) the Late Cretaceous to Early Tertiary (Laramide) Syrian arc system, due to closing of the Tethys (3) the Oligo-Miocene Gulf of Suez rifted basin, and (4) the Late Miocene to Recent transform Dead Sea-Gulf of Aqaba rift. Moreover, the shear zones inside Sinai have affected intensely the structure development of the northern Sinai area. 2-D fast Fourier transform (FFT) analysis has been applied to transfer the data from space domain to frequency domain, in which basic gradients and derived gradients have been estimated. The frequency domain operations resulted in frequency filtering, first and second degree xyz gradients, horizontal, total (analytical signal) and tilt gradients, maximum horizontal gradient amplitude (total horizontal derivative), and theta map. As a result, the basic and derived gradient maps have succeeded to outline the major structure elements of Northern Sinai Peninsula. Comparisons with some well known surface structures showed a large degree of matching.

  7. Water-gas dynamics and coastal land subsidence over Chioggia Mare field, northern Adriatic Sea

    NASA Astrophysics Data System (ADS)

    Teatini, Pietro; Baú, Domenico; Gambolati, Giuseppe

    2000-09-01

    A major development programme comprising 15 gas fields of the northern Adriatic Sea has recently been submitted to the Ministry of the Environment, VIA Committee for the assessment of the environmental impact, by ENI-Agip, the Italian national oil company. One of the largest reservoirs is Chioggia Mare, located about 10 km offshore of the Venetian littoral, with a burial depth of 1000-1400 m. The planned gas production from this field is expected to impact the shoreline stability with a potential threat to the city of Venice, 25 km northwest of the center of Chioggia Mare. To evaluate the risk of anthropogenic land subsidence due to gas withdrawal, a numerical model was developed that predicts the compaction of both the gas-bearing formations and the lateral/bottom aquifer (water drive) during a 13-year producing and a 12-year post-production period, and the transference of the deep compaction to the ground surface. To address the uncertainty of a few important hydromechanical parameters, several scenarios are simulated and the most pessimistic predictions obtained. The modeling results show that at most 1 cm of land subsidence over 25 years may be expected at the city of Chioggia, whereas Venice is not subject to settlement. If aquifer drawdown is mediated by water injection, land subsidence is arrested 5 km offshore, with the Chioggia littoral zone experiencing a rebound of 0.6-0.7 cm. Résumé. Un important programme de développement portant sur 15 gisements de gaz du nord de l'Adriatique a été récemment soumis au Comité VIA pour l'évaluation de l'impact sur l'environnement du Ministère de l'Environnement, par la société ENI-Agip, la compagnie nationale pétrolière italienne. L'un des plus importants réservoirs est celui de Chioggia Mare, situé à environ 10 km au large du littoral vénitien, à une profondeur de 1000 à 1400 m. La production de gaz prévue pour ce gisement laisse envisager un impact sur la stabilité du trait de côte, avec une

  8. Variation of char structure during anthracite pyrolysis catalyzed by Fe{sub 2}O{sub 3} and its influence on char combustion reactivity

    SciTech Connect

    Xuzhong Gong; Zhancheng Guo; Zhi Wang

    2009-09-15

    Effects of Fe{sub 2}O{sub 3} on the pyrolysis reactivity of demineralized anthracite were investigated by a thermo-gravimetric analyzer, indicating that pyrolysis reactivity of Fe{sub 2}O{sub 3}-loaded demineralized anthracite was higher than that of raw demineralized anthracite when temperature is over 500{sup o}C. Chars were prepared from the two coal samples in muffle with heating progress, and their structures were analyzed using SEM, FTIR, XRD, and Raman. FTIR results showed that absorption peaks of functional groups on the surface of char from catalytic pyrolysis at 700{sup o}C were more than that of char from noncatalytic pyrolysis. Raman results demonstrated values of (I{sub D3} + I{sub D4})/IG of chars from catalytic pyrolysis and noncatalytic pyrolysis were 4.76 and 3.86, respectively, indicating that ordering of the char was decreased by Fe{sub 2}O{sub 3}. XRD analysis revealed that diffraction angle of the 002 peak did not shift; however, L{sub a} and L{sub c} decreased, indicating degree of graphitization for microcrystalline structure of char from catalytic pyrolysis was decreased. The results of FTIR, XRD, and Raman of the char showed that catalytic pyrolysis improved the formation of free radicals, while hindered polymerization and forming of basic structure units. Finally, combustion reactivity of the three chars, including char of raw demineralized anthracite (char-A), char of Fe{sub 2}O{sub 3}-loaded demineralized anthracite (char-B), and char of Fe{sub 2}O{sub 3}-loaded demineralized anthracite washed by HCl (char-C), was investigated using TG and indicated that their active order was char-B > char-C > char-A. The results corroborated that Fe{sub 2}O{sub 3} changed structure of anthracite char and improved combustion reactivity.

  9. Successional trends in Sonoran Desert abandoned agricultural fields in northern Mexico

    USGS Publications Warehouse

    Castellanos, A.E.; Martinez, M.J.; Llano, J.M.; Halvorson, W.L.; Espiricueta, M.; Espejel, I.

    2005-01-01

    Excessive ground-water use and saline intrusion to the aquifer led, in less than three decades, to an increase in abandoned agricultural fields at La Costa de Hermosillo, within the Sonoran Desert. Using a chronosequence from years since abandonment, patterns of field succession were developed. Contrary to most desert literature, species replacement was found, both in fields with and without saline intrusion. Seasonal photosynthetic capacity as well as water and nitrogen use efficiencies were different in dominant early and late successional plant species. These ecological findings provided a framework for a general explanation of species dominance and replacement within abandoned agricultural fields in the Sonoran Desert. ?? 2004 Elsevier Ltd. All rights reserved.

  10. Estimating biodiversity impacts without field surveys: A case study in northern Borneo.

    PubMed

    Kitzes, Justin; Shirley, Rebekah

    2016-02-01

    In many regions of the world, biodiversity surveys are not routinely conducted prior to activities that lead to land conversion, such as development projects. Here we use top-down methods based on global range maps and bottom-up methods based on macroecological scaling laws to illuminate the otherwise hidden biodiversity impacts of three large hydroelectric dams in the state of Sarawak in northern Borneo. Our retrospective impact assessment finds that the three reservoirs inundate habitat for 331 species of birds (3 million individuals) and 164 species of mammals (110 million individuals). A minimum of 2100 species of trees (900 million individuals) and 17 700 species of arthropods (34 billion individuals) are estimated to be affected by the dams. No extinctions of bird, mammal, or tree species are expected due to habitat loss following reservoir inundation, while 4-7 arthropod species extinctions are predicted. These assessment methods are applicable to any data-limited system undergoing land-use change.

  11. Anisotropy of magnetic susceptibility in diamagnetic limestones reveals deflection of the strain field near the Dead Sea Fault, northern Israel

    NASA Astrophysics Data System (ADS)

    Issachar, R.; Levi, T.; Marco, S.; Weinberger, R.

    2015-08-01

    To exploit the potential of anisotropy of magnetic susceptibility (AMS) as a tool to estimate the strain field around major faults, we measured the AMS of calcite-bearing diamagnetic rocks that crop out next to the Dead Sea Fault (DSF) in northern Israel. Through integrated magnetic and geochemical methods we found that the rocks are almost pure calcite rocks and therefore the magnetic fabric is primarily controlled by preferred crystallographic orientation (PCO) with the minimum principal AMS axes (k3) parallel to calcite c-axes. We applied a separation procedure in several samples with high Fe content in order to calculate the AMS anisotropy parameters and compare them to pure diamagnetic rocks. AARM, thermo-susceptibility curves and IRM were used to characterize the magnetic phases. We found that for Fe content below 500 ppm the AMS is mostly controlled by the diamagnetic phase and showed that differences in the degree of anisotropy P' up to 3% (P' = 1.005 to 1.023) and in anisotropy difference Δk (up to ~ 0.25 × 10- 6 SI) in diamagnetic rocks are related to differences of strain magnitudes. The spatial distribution of the magnetic fabrics indicates ~ N-S maximum shortening parallel to the strike of the Hula Western Border fault (HWBF), one of the main strands of the DSF in northern Israel. The anisotropy parameters suggest that the strain magnitudes increase eastward with the proximity to the HWBF. These results suggest that the strain field near the HWBF is locally deflected as a consequence of the DSF activity. In light of the "fault weakness" model and geological setting of the study area, we suggest that the area accommodates dominant transtension during the Pleistocene. The present study demonstrates the useful application of AMS measurements in "iron-free" limestones as recorders of the strain field near plate boundaries.

  12. Downflow limestone beds for treatment of net-acidic, oxic, iron-laden drainage from a flooded anthracite mine, Pennsylvania, USA: 2. Laboratory evaluation

    USGS Publications Warehouse

    Cravotta, C.A.; Ward, S.J.; Hammarstrom, J.M.

    2008-01-01

    Acidic mine drainage (AMD) containing elevated concentrations of dissolved iron and other metals can be neutralized to varying degrees by reactions with limestone in passive treatment systems. We evaluated the chemical and mineralogical characteristics and the effectiveness of calcitic and dolomitic limestone for the neutralization of net-acidic, oxic, iron-laden AMD from a flooded anthracite mine. The calcitic limestone, with CaCO3 and MgCO3 contents of 99.8 and <0.1 wt%, respectively, and the dolomitic limestone, with CaCO3 and MgCO3 contents of 60.3 and 40.2 wt%, were used to construct a downflow treatment system in 2003 at the Bell Mine, a large source of AMD and baseflow to the Schuylkill River in the Southern Anthracite Coalfield, in east-central Pennsylvania. In the winter of 2002-2003, laboratory neutralization-rate experiments evaluated the evolution of effluent quality during 2 weeks of continuous contact between AMD from the Bell Mine and the crushed calcitic or dolomitic limestone in closed, collapsible containers (cubitainers). The cubitainer tests showed that: (1) net-alkaline effluent could be achieved with detention times greater than 3 h, (2) effluent alkalinities and associated dissolution rates were equivalent for uncoated and Fe(OH)3-coated calcitic limestone, and (3) effluent alkalinities and associated dissolution rates for dolomitic limestone were about half those for calcitic limestone. The dissolution rate data for the cubitainer tests were used with data on the volume of effuent and surface area of limestone in the treatment system at the Bell Mine to evaluate the water-quality data for the first 1.5 years of operation of the treatment system. These rate models supported the interpretation of field results and indicated that treatment benefits were derived mainly from the dissolution of calcitic limestone, despite a greater quantity of dolomitic limestone within the treatment system. The dissolution-rate models were extrapolated on a

  13. Utilization of AMD sludges from the anthracite region of Pennsylvania for removal of phosphorus from wastewater

    USGS Publications Warehouse

    Sibrell, P.L.; Cravotta, C.A.; Lehman, W.G.; Reichert, W.

    2010-01-01

    Excess phosphorus (P) inputs from human sewage, animal feeding operations, and nonpoint source discharges to the environment have resulted in the eutrophication of sensitive receiving bodies of water such as the Great Lakes and Chesapeake Bay. Phosphorus loads in wastewater discharged from such sources can be decreased by conventional treatment with iron and aluminum salts but these chemical reagents are expensive or impractical for many applications. Acid mine drainage (AMD) sludges are an inexpensive source of iron and aluminum hydrous oxides that could offer an attractive alternative to chemical reagent dosing for the removal of P from local wastewater. Previous investigations have focused on AMD sludges generated in the bituminous coal region of western Pennsylvania, and confirmed that some of those sludges are good sorbents for P over a wide range of operating conditions. In this study, we sampled sludges produced by AMD treatment at six different sites in the anthracite region of Pennsylvania for potential use as P sequestration sorbents. Sludge samples were dried, characterized, and then tested for P removal from water. In addition, the concentrations of acid-extractable metals and other impurities were investigated. Test results revealed that sludges from four of the sites showed good P sorption and were unlikely to add contaminants to treated water. These results indicate that AMD sludges could be beneficially used to sequester P from the environment, while at the same time decreasing the expense of sludge disposal.

  14. Highly porous activated carbons prepared from carbon rich Mongolian anthracite by direct NaOH activation

    NASA Astrophysics Data System (ADS)

    Byamba-Ochir, Narandalai; Shim, Wang Geun; Balathanigaimani, M. S.; Moon, Hee

    2016-08-01

    Highly porous activated carbons (ACs) were prepared from Mongolian raw anthracite (MRA) using sodium hydroxide as an activation agent by varying the mass ratio (powdered MRA/NaOH) as well as the mixing method of chemical agent and powdered MRA. The specific BET surface area and total pore volume of the prepared MRA-based activated carbons (MACs) are in the range of 816-2063 m2/g and of 0.55-1.61 cm3/g, respectively. The pore size distribution of MACs show that most of the pores are in the range from large micropores to small mesopores and their distribution can be controlled by the mass ratio and mixing method of the activating agent. As expected from the intrinsic property of the MRA, the highly graphitic surface morphology of prepared carbons was confirmed from Raman spectra and transmission electron microscopy (TEM) studies. Furthermore the FTIR and XPS results reveal that the preparation of MACs with hydrophobic in nature is highly possible by controlling the mixing conditions of activating agent and powdered MRA. Based on all the results, it is suggested that the prepared MACs could be used for many specific applications, requiring high surface area, optimal pore size distribution, proper surface hydrophobicity as well as strong physical strength.

  15. Size effects in the conduction electron spin resonance of anthracite and higher anthraxolite.

    PubMed

    Tadyszak, Krzysztof; Strzelczyk, Roman; Coy, Emerson; Maćkowiak, Mariusz; Augustyniak-Jabłokow, Maria A

    2016-03-01

    Electron paramagnetic resonance spectroscopy of conduction electrons, i.e. Conduction Electron Spin Resonance (CESR), is a powerful tool for studies of carbon samples. Conductive samples cause additional effects in CESR spectra that influence the shape and intensity of the signals. In cases where conduction electrons play a dominant role, whilst the influence of localized paramagnetic centres is small or negligible, the effects because of the spins on conduction electrons will dominate the spectra. It has been shown that for some ratios of the bulk sample sizes (d) to the skin depth (δ), which depend on the electrical conductivity, additional size effects become visible in the line asymmetry parameter A/|B|, which is the ratio of the maximum to the absolute, minimum value of the resonance signal. To study these effects the electrical direct current-conductivity and CESR measurements are carried out for two amorphous bulk coal samples of anthracite and a higher anthraxolite. The observed effects are described and discussed in terms of the Dyson theory. Copyright © 2015 John Wiley & Sons, Ltd.

  16. Geological probability calculation of new gas discoveries in wider area of Ivana and Ika Gas Fields, Northern Adriatic, Croatia

    NASA Astrophysics Data System (ADS)

    Tomislav, Malvić; Josipa, Velić; Režić, Mate

    2016-09-01

    There are eleven reservoirs in Ivana Gas Field and they are composed of Pleistocene sands, silt sands and siltstones, developed in dominant clays and marls depositional sequences. Ika Gas Field is the only field in Adriatic with gas accumulated in carbonate rocks, which are the deepest reservoir of the total four reservoirs. A carbonate reservoir is defined with tectonical and erosional unconformity, which is placed between Mesozoic and Pliocene rocks. The three younger Ika reservoirs are composed of Pleistocene sands, silt sands and siltstones that are laminated into clays and marls. The goal of our study was to assess the `Probability Of Success' (POS) of finding new gas accumulations within the marginal area of those two fields, either in the form of Mesozoic rocks or Pleistocene deposits. The assessment was successfully completed using the Microsoft Excel POS table for the analyzed areas in the Croatian part of the Po Depression, namely, Northern Adriatic. The methodology was derived and adapted from a similar POS calculation, which was originally used to calculate the geological probability of hydrocarbon discoveries in the Croatian part of the Pannonian Basin System (CPBS).

  17. Historical ecology of the northern Adriatic Sea: Field methods and coring device

    NASA Astrophysics Data System (ADS)

    Haselmair, Alexandra; Gallmetzer, Ivo; Tomasovych, Adam; Stachowitsch, Michael; Zuschin, Martin

    2014-05-01

    For an ongoing study on the historical ecology of the northern Adriatic Sea, the objective was to retrieve a high number of sediment cores at seven sampling stations spread across the entire basin. One set of cores is intended for sediment analyses including radiometric Pb-sediment-dating, grain size, TOC, TAC and heavy metal analyses. The other set of cores delivered enough shelly remains of endo- or epibenthic hard part producers (e.g. molluscs, crustaceans, echinoderms) to enable the reconstruction of death assemblages in core layers from top to bottom. The down-core changes of such assemblages record ecological shifts in a marine environment that has endured strong human impacts over several centuries. A 1.5 m-long core could, according to the available sedimentation data for the area, cover up to 2000 or even more years of ecological history. The coring method had to meet the following requirements: a) deliver 1.5-m-long cores from different sediment settings (mud to sand, reflecting a wide range of benthic habitats in the northern Adriatic); b) enable quick and easy deployment to ensure that multiple cores can be taken at the individual sampling stations within a short time; c) be relatively affordable and allow handling by the researchers themselves, potentially using a small vessel in order to further contain the operating costs. Two types of UWITEC™ piston corers were used to meet these requirements. A model with 90 mm of diameter (samples for sediment analysis) and another one with 160 mm, specifically designed to obtain the large amount of material needed for shell analysis, successfully delivered a total of 54 cores. The device consists of a stabilizing tripod and the interchangeable coring cylinders. It is equipped with a so-called hammer action that makes it possible, at least for the smaller cylinder, to penetrate even harder sediments. A closing mechanism of the corer retains the sediment in the cylinder upon extraction; it works either

  18. Interannual variability in Saharan dust over the North Atlantic Ocean and its relation to meteorological fields during northern winter

    NASA Astrophysics Data System (ADS)

    Nakamae, K.; Shiotani, M.

    2013-03-01

    In this study, we focus on interannual variability in Saharan dust transport over the North Atlantic Ocean during northern winter using the Aerosol Index data from the Total Ozone Mapping Spectrometer (TOMS). Since the TOMS observations provide a long-term global record, they are useful for considering interannual variations of the Saharan dust in relation to the North Atlantic Oscillation (NAO). We calculated correlation coefficients between the NAO Index and the TOMS AI averaged over the northern winter season. Using the correlation map, we defined three regions: Region 1 is in positive correlation over the North Atlantic Ocean, Region 2 is in insignificant correlation over the west Sahara, and Region 3 is in negative correlation over the east Sahara. Focusing on Region 1, we considered the relationship between the regional mean TOMS AI time series and certain meteorological parameters. We used sea level pressure and wind speed fields to represent the synoptic circulation, and virtual temperature and lifting condensation level (LCL) to represent the mixed layer condition. When the TOMS AI in Region 1 is large, the easterly winds over the west Sahara are stronger than usual compared to the NAO, and the virtual temperature is higher than average over the ocean. As a result, the LCL is higher near 20°W-0° and is lower than average over the desert. When dust outflow events are observed over the North Atlantic Ocean, strong winds with a high pressure blow in the west Sahara, and dust containing warm air parcels is carried by these strong winds to ocean through areas near the coast (20°N-30°N, 15°W-10°W) from the west Sahara. We summarized the features of meteorological fields during dust outflow events.

  19. Phosphorus removal by laboratory-scale unvegetated vertical-flow constructed wetland systems using anthracite, steel slag and related blends as substrate.

    PubMed

    Wu, Junmei; He, Feng; Xu, Dong; Wang, Rong; Zhang, Xiangling; Xiao, Enrong; Wu, Zhenbin

    2011-01-01

    This research aimed to investigate the phosphorus (P) removal of a series of laboratory-scale unvegetated vertical-flow constructed wetland systems using anthracite, steel slag and related blends as substrate in treatment of low concentration domestic sewage. The long-term performance of P removal was firstly studied by using single substrate of anthracite or steel slag, and three systems applying various combined substrates were investigated when the average P loading rate varied between 0.9 and 1.5 g TP/m2 x d. The results demonstrated that both anthracite and steel slag systems were highly effective in removing total P (CTP, 77.17 +/- 23.34% and 90.26 +/- 4.48%) and soluble reactive P (SRP, 92.14 +/- 12.56% and 96.20 +/- 2.58%). The system filled with anthracite, vermiculite and steel slag from the top down removed 82.45 +/- 9.52% and 87.83 +/- 8.58% of TP and SRP, respectively. However, other combined substrate systems showed comparative low and fluctuant P removal. The effluent pH was maintained at 7-9, which met environmental requirements of China. Therefore, anthracite provides a long-term high efficiency of P removal and may be a promising substrate from the standpoint of the effluent pH, and the arrangement of combined substrate has a prominent effect on P removal.

  20. Selection of flooded agricultural fields and other landscapes by female northern pintails wintering in Tulare Basin, California

    USGS Publications Warehouse

    Fleskes, Joseph P.; Jarvis, Robert L.; Gilmer, David S.

    2003-01-01

    Habitat selection and use are measures of relative importance of habitats to wildlife and necessary information for effective wildlife conservation. To measure the relative importance of flooded agricultural fields and other landscapes to northern pintails (Anas acuta) wintering in Tulare Basin (TB), California, we radiotagged female pintails during late August-early October, 1991-1993 in TB and other San Joaquin Valley areas and determined use and selection of these TB landscapes through March each year. Availability of landscape and field types in TB changed within and among years. Pintail use and selection (based upon use-to-availability log ratios) of landscape and field types differed among seasons, years, and diel periods. Fields flooded after harvest and before planting (i.e., pre-irrigated) were the most available, used, and selected landscape type before the hunting season (Prehunt). Safflower was the most available, used, and-except in 1993, when pre-irrigated fallow was available-selected pre-irrigated field type during Prehunt. Pre-irrigated barley-wheat received 19-22% of use before hunting season, but selection varied greatly among years and diel periods. During and after hunting season, managed marsh was the most available, used, and, along with floodwater areas, selected landscape type; pre-irrigated cotton and alfalfa were the least selected field types and accounted for <13% of pintail use. Agricultural drainwater evaporation ponds, sewage treatment ponds, and reservoirs accounted for 42-48% of flooded landscape available but were little used and least selected. Exodus of pintails from TB coincided with drying of pre-irrigated fallow, safflower, and barley-wheat fields early in winter, indicating that preferred habitats were lacking in TB during late winter. Agriculture conservation programs could improve TB for pintails by increasing flooding of fallow and harvested safflower and grain fields. Conservation of remaining wetlands should concentrate

  1. Selection of flooded agricultural fields and other landscapes by female northern pintails wintering in Tulare Basin, California

    USGS Publications Warehouse

    Fleskes, Joseph P.; Jarvis, Robert L.; Gilmer, David S.

    2003-01-01

    Habitat selection and use are measures of relative importance of habitats to wildlife and necessary information for effective wildlife conservation. To measure the relative impor- tance of flooded agricultural fields and other landscapes to northern pintails (Anas acuta) wintering in Tulare Basin (TB), California, we radiotagged female pintails during late August-early October, 1991-1993 in TB and other San Joaquin Valley areas and deter- mined use and selection of these TB landscapes through March each year. Availability of landscape and field types in TB changed within and among years. Pintail use and selec- tion (based upon use-to-availability log ratios) of landscape and field types differed among seasons, years, and diel periods. Fields flooded after harvest and before planting (i.e., pre-irrigated) were the most available, used, and selected landscape type before the hunting season (Prehunt). Safflower was the most available, used, and-except in 1993, when pre-irrigated fallow was available-selected pre-irrigated field type during Prehunt. Pre-irrigated barley-wheat received 19-22% of use before hunting season, but selection varied greatly among years and diel periods. During and after hunting season, managed marsh was the most available, used, and, along with floodwater areas, selected landscape type; pre-irrigated cotton and alfalfa were the least selected field types and accounted for <13% of pintail use. Agricultural drainwater evaporation ponds, sewage treatment ponds, and reservoirs accounted for 42-48% of flooded landscape available but were lit- tle used and least selected. Exodus of pintails from TB coincided with drying of pre-irri- gated fallow, safflower, and barley-wheat fields early in winter, indicating that preferred habitats were lacking in TB during late winter. Agriculture conservation programs could improve TB for pintails by increasing flooding of fallow and harvested safflower and grain fields. Conservation of remaining wetlands should

  2. The Cerro Bitiche Andesitic Field: petrological diversity and implications for magmatic evolution of mafic volcanic centers from the northern Puna

    NASA Astrophysics Data System (ADS)

    Maro, Guadalupe; Caffe, Pablo J.

    2016-07-01

    The Cerro Bitiche Andesitic Field (CBAF) is one of the two largest mafic volcanic fields in northern Puna (22-24° S) and is spatially and temporally associated with ignimbrites erupted from some central Andean Altiplano-Puna Volcanic Complex calderas. The CBAF comprises seven scoria cones and widespread high-K calcalkaline lava flows that cover an area of 200 km2. Although all erupted rocks have a relatively narrow chemical range (56-62 % SiO2, 3-6 % MgO), there is a broad diversity of mineral compositions and textures. The least evolved lavas (˜58-61 % SiO2) are high-Mg andesites with scarce (<10 %) microphenocrysts of either olivine or orthopyroxene. The small compositional range and low phenocryst content indicate evolution controlled by low percentages (<10 %) of fractional crystallization of olivine and clinopyroxene of magmas similar to the least evolved rocks from the field, accompanied by assimilation during rapid ascent through the crust. Evolved andesites (˜62 wt% SiO2), on the other hand, are porphyritic rocks with plagioclase + orthopyroxene + biotite and ubiquitous phenocryst disequilibrium textures. These magmas were likely stored in crustal reservoirs, where they experienced convection caused by mafic magma underplating, magma mixing, and/or assimilation. Trace element and mineral compositions of CBAF lavas provide evidence for complex evolution of distinct magma batches.

  3. Overview for geologic field-trip guides to volcanoes of the Cascades Arc in northern California

    USGS Publications Warehouse

    Muffler, L. J. Patrick; Donnelly-Nolan, Julie M.; Grove, Timothy L.; Clynne, Michael A.; Christiansen, Robert L.; Calvert, Andrew T.; Ryan-Davis, Juliet

    2017-08-15

    The California Cascades field trip is a loop beginning and ending in Portland, Oregon. The route of day 1 goes eastward across the Cascades just south of Mount Hood, travels south along the east side of the Cascades for an overview of the central Oregon volcanoes (including Three Sisters and Newberry Volcano), and ends at Klamath Falls, Oregon. Day 2 and much of day 3 focus on Medicine Lake Volcano. The latter part of day 3 consists of a drive south across the Pit River into the Hat Creek Valley and then clockwise around Lassen Volcanic Center to the town of Chester, California. Day 4 goes from south to north across Lassen Volcanic Center, ending at Burney, California. Day 5 and the first part of day 6 follow a clockwise route around Mount Shasta. The trip returns to Portland on the latter part of day 6, west of the Cascades through the Klamath Mountains and the Willamette Valley. Each of the three sections of this guidebook addresses one of the major volcanic regions: Lassen Volcanic Center (a volcanic field that spans the volcanic arc), Mount Shasta (a fore-arc stratocone), and Medicine Lake Volcano (a rear-arc, shield-shaped edifice). Each section of the guide provides (1) an overview of the extensive field and laboratory studies, (2) an introduction to the literature, and (3) directions to the most important and accessible field localities. The field-trip sections contain far more stops than can possibly be visited in the actual 6-day 2017 IAVCEI excursion from Portland. We have included extra stops in order to provide a field-trip guide that will have lasting utility for those who may have more time or may want to emphasize one particular volcanic area.

  4. Liquid and Emulsified Sulfur in Submarine Solfatara Fields of two Northern Mariana Arc Volcanoes.

    NASA Astrophysics Data System (ADS)

    Nakamura, K.; Embley, R. W.; Chadwick, W. W.; Butterfield, D. A.; Takano, B.; Resing, J. A.; de Ronde, C. E.; Lilley, M. D.; Lupton, J. E.; Merle, S. G.; Inagaki, F.

    2006-12-01

    Because elemental sulfur melting point is ca 100 deg C (depend on allotropes and heating rate, S8 triple point temperature: 115 deg C), the evidence of liquid sulfur has been known for many subaerial crater lakes and small ponds in geothermal regions throughout the world. But the milky nature of water (sulfur-in- water emulsion in limited water mass) prohibited the direct observation of on-going processes at the bottom of these subaerial lakes. In the passive degassing environment at the summit craters of Daikoku and Nikko Seamounts of the northern Mariana Arc, the continuous flushing of sulfur emulsion by seawater allowed us to observe on- going submarine solfatara processes and associated chemistry through dives with ROVs during the NT05-18 cruise (JAMSTEC R/V Natsushima and ROV hyper-Dolphin) and the Submarine Ring of Fire 2006 cruise (R/V Melville and ROV JASON II). A higher viscosity for liquid elemental sulfur relative to that of seawater, as well as a limited stability of sulfur emulsion (aqueous sulfur sol) at high temperatures in electrolyte solution (seawater), ensures limited mobility of liquid sulfur in the conduits of hydrothermal vents. The subseafloor boiling depth of hydrothermal fluid limits the locus of any liquid sulfur reservoir. It was observed in an exposed liquid sulfur pond that the penetration of gas bubbles (mostly CO2) created sulfur emulsion while collapsing liquid sulfur film between seawater and gas bubbles. Liquid sulfur pits, encrusted sulfur, liquid sulfur fountain structure, sulfur stalactites and stalagmites, mini-pillow lava-like sulfur flows, accretionary sulfur lapilli and sulfur deltas were also observed at the summits of two volcanoes. Note: Solfatara: Italian. A type of fumarole, the gases of which are characteristically sulfurous. In 'Glossary of geology.'

  5. Factors affecting farmers' behaviour in pesticide use: Insights from a field study in northern China.

    PubMed

    Fan, Liangxin; Niu, Haipeng; Yang, Xiaomei; Qin, Wei; Bento, Célia P M; Ritsema, Coen J; Geissen, Violette

    2015-12-15

    Quantitative understanding of farmers' behaviour in pesticide use is critical to enhance sustainability of chemical pest control and protect farmers' health and the environment. However, reports on the levels of knowledge and awareness of farmers and the practices of pesticide use are often insufficient. Here, we conducted a comprehensive analysis on the effects of knowledge and awareness of farmers as well as the influence of the associated stakeholders (i.e. pesticide retailers and the government) on farmers' behaviour in pesticide use by using a detailed survey of 307 agricultural households (79 grain farms, 65 fruit farms, 53 vegetable farms and 110 mixed-crop farms) in the Wei River basin in northern China. Eight protective behaviours (PBs) were exhibited by farmers. Careful and safe storage of pesticides, changing clothes or showering after applying pesticides, and reading instructions of the container labels before application were the most frequent PBs. Vegetable and fruit farmers had higher levels of education and knowledge than grain farmers, but the former were less willing to reduce pesticide use because of fear of low profits and lack of trust in the government and pesticide retailers. The PBs of farmers were strongly affected by the perception of the consequences of their behaviour (standardised path coefficient, SPC=0.42) and the level of farmers' knowledge (SPC=0.33). Pesticide retailers and the government had a moderate and weak influence, respectively, on farmers' PBs, suggesting a large gap of trust among farmers, pesticide retailers, and the government. Training and supervising retailers, educating farmers, and improving information transparency across farmers, pesticide retailers and the staff of the Agricultural Extension and Technology Service are recommended for bridging the gap of trust between farmers and the associated stakeholders as well as for promoting the use of PBs among farmers. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Soil-vegetation-atmosphere processes: Simulation and field measurement for deforested sites in northern Thailand

    NASA Astrophysics Data System (ADS)

    Giambelluca, Thomas W.; Tran, Liem T.; Ziegler, Alan D.; Menard, Trae P.; Nullet, Michael A.

    1996-11-01

    In recent efforts to predict the climatic impacts of tropical deforestation an extreme scenario of impoverished grassland has been used to represent the future deforested landscape. Currently, deforested areas of the tropics are composed of a mosaic of crops, bare soil, grassland, and secondary vegetation of various ages. The dominant feature of deforested land is often secondary vegetation. Parameter values for important forest replacement land covers, including secondary vegetation, have been shown to differ from those of forest much less than that assumed in general circulation model (GCM) deforestation experiments. For this study, the biosphere-atmosphere transfer scheme (BATS) is run in uncoupled mode using measured input data in place of GCM forcing and using the same parameter settings employed in recent deforestation experiments. Model output is compared with measurements taken over seven different deforested land surfaces in northern Thailand. Comparisons reveal that the simulation of deforested land overestimates reflected shortwave radiation, the diurnal range of surface temperature for secondary vegetation, surface soil moisture loss during periods without rain, and surface soil moisture increase at the start of a rainy period and underestimates net radiation, the diurnal range of surface temperature on recently used land surfaces, and root zone soil moisture increase at the start of a rainy period at most sites. Most deforested land surfaces, especially intermediate and advanced secondary vegetation, are more similar, in terms of land surface-atmosphere interaction, to the model simulation of forest than of deforested land as depicted in GCM experiments. These comparisons suggest that modelers aspiring to make realistic simulations of deforestation should adopt parameter settings representative of the diverse range of forest replacement land covers, instead of again using the grassland scenario.

  7. Arguments for Integration in the Field of Education in Northern Michigan

    ERIC Educational Resources Information Center

    Beardslee, Lois

    2004-01-01

    As a Native American with advanced college training in the field of education in northwest lower Michigan, the author has increasingly encountered denial on the part of educational professionals in the region as a response to statistics on race. During 2002, she spent nine months reviewing and renewing her statistical sources for use in nonfiction…

  8. Field trip overview: habitat loss and plant invasions in northern Utah's Basin and Range

    USDA-ARS?s Scientific Manuscript database

    An all-day field trip was conducted on May 19, 2010, as part of the 16th Wildland Shrub Symposium program. The tour consisted of Tour A and Tour B, which visited Utah's west desert shrublands in Park Valley (Tour A), and Bear River Mountains montane shrublands and Hardware Ranch Wildlife Management...

  9. Geologic field-trip guide to the Lassen segment of the Cascades Arc, northern California

    USGS Publications Warehouse

    Clynne, Michael A.; Muffler, L. J. Patrick

    2017-08-17

    This field-trip guide provides an overview of Quaternary volcanism in and around Lassen Volcanic National Park, California, emphasizing the stratigraphy of the Lassen Volcanic Center. The guide is designed to be self-guided and to focus on geologic features and stratigraphy that can be seen easily from the road network.

  10. Vegetation changes of sand fields in Northern China in response to climatic change, 1982-2013

    NASA Astrophysics Data System (ADS)

    Yuan, W.; Wu, S. Y.; Hou, S.

    2016-12-01

    The semi-arid region in North China is one of the areas that has experienced expansion of sand fields in recent decades with serious consequences on the lives of hundreds of million people. How these sand fields respond to global warming is an important scientific question with great practical significance. This study focuses on the four major sand fields in this region, i.e. Hulunbeeir, Horqin, Otindag and Mu Us, and examines the past vegetation changes in response to climate change. Based on a comparison of common satellite datasets (SPOT, MODIS, GIMMS), the GIMMS NDVI product is selected for its relatively long time span and stability. We use both linear regression and nonparametric Greenness Rate of Change (GRC) index to calculate the trends, and both results are highly consistent with each other. Our results show that during the study period of 1982-2013, Mu Us, the southernmost sand field, experienced the largest amount of greening, whereas most of the other sand fields experienced little changes. NDVI showed most increase in the warm seasons (summer and fall), and generally decreased in winter. Spatial variations exists with such trends. For most of the sandy fields, NDVI increased in the South and East, and decreased in the North and West. These changes could be related to the decline of Eastern Asian Summer Monsoon in recent decades, which tends to increase precipitation in the South and decrease it in the North. Using ERA-Interim reanalysis data, we examine the relationship between NDVI and a variety of climate factors. We found that NDVI is most closely associated with temperature, evaporation, precipitation, surface sensible heat flux, and wind. A multiple linear regression model shows that these factors together could explain 76% of the total variance in NDVI. Using relative weights to assess the independent contribution of these variables, we found that the most important factor is temperature, followed by precipitation and evaporation, wind and

  11. Advancement of 10 t/h fluidized bed boiler burning Fujian anthracite with extremely low volatile[ity

    SciTech Connect

    Zhao, C.; Duan, Y.; Chen, X.; Wu, X.; Wu, S.; Wang, W.; Huang, C.

    1999-07-01

    The anthracite in Fujian Province, China with extremely low volatile content about 2--4% is very difficult to burn in grate firing boilers, and operation conditions are very poor, such as steam output well below the nominal capacity and very low burning-out rate. Burning Fujian anthracite in specially designed bubbling fluidized bed (BFB) boilers with capacities between 4 T/H and 20 T/H are still unsatisfactory. In order to increase boiler output and utilize local coal more efficiently, a 10 T/H BFB boiler burning Fujian anthracite was retrofitted with several special techniques, in terms of underbed feeding of recycling fly ash, vortexing secondary air injection, continuous bottom ash removal and adding immersed tube surface. The boiler performances before and after the retrofitting were measured and compared. The experimental results indicate that steam output of the boiler is boosted from 7--8 T/H to more than 14 T/H, unburned carbon content (UBC) in ash from the convective banks drops from 31.39% to 3.89%, UBC in ash from the multicyclone drops from 38.87% to 22.19%, and UBC in fly ash drops from 35.3% to 18.07%. The boiler thermal efficiency increases from 67.27% to 82.93%. Boiler operation becomes more stable. Particulate emission is substantially lessened because of separation by the vortexing secondary air. The retrofitting was completely successful. The technique used and experiences obtained in the retrofitting can be widely applied in industrial BFB boilers.

  12. Geologic field-trip guide to Medicine Lake Volcano, northern California, including Lava Beds National Monument

    USGS Publications Warehouse

    Donnelly-Nolan, Julie M.; Grove, Timothy L.

    2017-08-17

    Medicine Lake volcano is among the very best places in the United States to see and walk on a variety of well-exposed young lava flows that range in composition from basalt to rhyolite. This field-trip guide to the volcano and to Lava Beds National Monument, which occupies part of the north flank, directs visitors to a wide range of lava flow compositions and volcanic phenomena, many of them well exposed and Holocene in age. The writing of the guide was prompted by a field trip to the California Cascades Arc organized in conjunction with the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) quadrennial meeting in Portland, Oregon, in August of 2017. This report is one of a group of three guides describing the three major volcanic centers of the southern Cascades Volcanic Arc. The guides describing the Mount Shasta and Lassen Volcanic Center parts of the trip share an introduction, written as an overview to the IAVCEI field trip. However, this guide to Medicine Lake volcano has descriptions of many more stops than are included in the 2017 field trip. The 23 stops described here feature a range of compositions and volcanic phenomena. Many other stops are possible and some have been previously described, but these 23 have been selected to highlight the variety of volcanic phenomena at this rear-arc center, the range of compositions, and for the practical reason that they are readily accessible. Open ground cracks, various vent features, tuffs, lava-tube caves, evidence for glaciation, and lava flows that contain inclusions and show visible evidence of compositional zonation are described and visited along the route.

  13. Geometry and evolution of a planar fault surface: Implications for the stress field orientation in the northern Walker Lane

    SciTech Connect

    Cashman, P.H. . Dept. of Geological Sciences); Power, W.L. )

    1993-04-01

    The authors present quantitative shape and roughness data to describe an extraordinarily planar fault surface in the southern Pah Rah Range, Washoe Co., Nevada. The planar nature of the fault surface is interpreted to be the result of alternating strike-slip and dip-slip motion during its formation. The most likely explanation for mixed mode faulting is repeated changes in the magnitudes or directions of the principal stresses. The orientation, slip directions, and faulting history from this fault surface constrain the regional stress field in the northern Walker Lane from Miocene time to the present. Mesoscopic structures record multiple reactivations of the fault. The fault is characterized by a 0--1 m thick zone of brecciated and comminuted rock. This gouge is recemented; frictional wear on clasts within the cemented gouge and on the gouge itself documents continued fault slip after the cementing occurred. The planar bedrock scarp is developed within the gouge, and is 1--1.5m high and 300m long. It is coated with a thin veneer of tan clayey material which is 1mm thick. The main bedrock scarp is cut by several sets of minor faults and shear zones; the planar fault surface serves as a marker horizon for determining relative displacement on these features. The fault is part of the left-lateral Olinghouse fault system in the northern Walker Lane. It crops out just north of the Truckee River, 25 km east of Reno, and cuts basaltic flow breccia of the Miocene Lousetown Fm. The planar fault surface strikes E-W and is sub-vertical; this differs from the 060[degree] strike of the Olinghouse system as a whole. Total displacement, based on gouge thickness, is at least 100--1,000m.

  14. Surface Measurements of dust/local aerosol properties over Northern China during 2008 China-US joined dust field campaign

    NASA Astrophysics Data System (ADS)

    Wang, X.; Huang, J.

    2009-12-01

    The objective of this study is to understand the detailed characteristics and underlying mechanisms of aerosol physical and optical parameters over China Loess Plateau and its potential impacts on the regional/global climate. In order to characterize the emission, transport, and removal of atmospheric pollutants emitted from East Asia, the 2008 China-US joined field campaign are conducted from late April to May 2008 focused specifically on the Asian direct measurements of dust and pollution transport, following the plume from the Northern China which from the Taklamakan desert and Gobi desert to the Eastern Pacific and into North America. Such measurements are crucial to understanding how the dust and the pollution plume (including black carbon) are modified as their age. Three sites involved this campaign, including one permanent site (Semi-Arid Climate & Environment Observatory of Lanzhou University (SACOL)) (located in Yuzhong, 35.95N/104.1E), one SACOL's Mobile Facility (SMF) (deployed in Jintai, 37.57N/104.23E) and the U.S. Department of Energy Atmospheric Radiation Measurements(ARM) Ancillary Facility (AAF mobile laboratories, SMART-COMMIT) (deployed in Zhangye, 39.08N/100.27E). Results indicate that the dust plumes are transported from the surface to a long distance from their sources have a significant influence on the air quality in the study area. The meteorological analysis indicates that these polluted layers are not from local sources during dust plume and this large-scale transport of dust and pollutants remains a major uncertainty in quantifying the global effect of emissions from Northern China.

  15. Buffer strip effect on terbuthylazine, desethyl-terbuthylazine and S-metolachlor runoff from maize fields in Northern Italy.

    PubMed

    Milan, Marco; Vidotto, Francesco; Piano, Serenella; Negre, Michèle; Ferrero, Aldo

    2013-01-01

    The effectiveness of a 6 m wide vegetative buffer strip for reducing runoff of S-metolachlor, terbuthylazine and desethyl-terbuthylazine was studied in 2007-2008 in Northern Italy. Two cultivated fields, with and without the buffer strip, were compared. Residues of the chemicals were investigated in runoff water collected after runoff events and their dissipation in the soil was studied. The highest concentration of the chemicals in water occurred in samples collected from the unbuffered field at the first runoff events. Losses of terbuthylazine and S-metolachlor in runoff waters were particularly high in 2007 (2.6% and 0.9% of the amount applied, respectively). Soil half-life of terbuthylazine and S-metolachlor ranged between 12.1 and 8.9 days and 16 and 7 days, respectively. The presence of desethyl-terbuthylazine was related to parent compound degradation. The buffer strip allowed an important reduction of chemical content in water (> 90%), in particular during the first runoff events.

  16. Studying the basement structure of the Ramså field on Andøya, northern Norway

    NASA Astrophysics Data System (ADS)

    Broenner, M.; Olesen, O.; Koziel, J.; Gellein, J.; Midbøe, P.; Henningsen, T.

    2009-12-01

    Whereas offshore on the Norwegian shelf and between the islands and the mainland deep Mesozoic basins still exist, Mesozoic sediments are generally absent on mainland Norway due to erosion processes. The Ramså field on Andøya, Vesterålen, Northern Norway is the only place in Norway with exposed Mesozoic rocks on land and thus provides an excellent place to study extensively the link between basement structures and sedimentary successions. A combined observation and interpretation of faulting and basement surfaces as well as a better knowledge of the different basement types allow a more accurate and differentiated interpretation of the tectonic setting and evolution of the region. With the aim to gain a better knowledge of the basement and the sedimentary structures, new high resolution aeromagnetic data and densely measured gravity data were acquired on Andøya, processed and interpreted to update the present geotectonic picture for the Ramså field. Magnetic data were used to map the structural elements of the area and to link them with geological observations. Furthermore Euler deconvolution techniques were applied to estimate the depth to magnetic sources and to identify fault systems. Gravity data were most sensitive to the varying sediment thickness and were consequently helpful to map the depth-to-basement. Stratigraphic information from four wells, drilled down to and into different basement types were used to establish a structural layer model of the Ramså field, which were assigned with petrophysical parameters based on NGU's comprehensive petrophysical database. The Ramså field is generally considered to represent a down-faulted block, bounded by sharp and steep faults to the surrounding exposed basement blocks. But the structural models, so far based on surface observations and well correlations, were never controlled and refined by using gravity and magnetic data. State of the art techniques and densely measured potential field data have the

  17. Imaging Seismic Source Variations Using Back-Projection Methods at El Tatio Geyser Field, Northern Chile

    NASA Astrophysics Data System (ADS)

    Kelly, C. L.; Lawrence, J. F.

    2014-12-01

    During October 2012, 51 geophones and 6 broadband seismometers were deployed in an ~50x50m region surrounding a periodically erupting columnar geyser in the El Tatio Geyser Field, Chile. The dense array served as the seismic framework for a collaborative project to study the mechanics of complex hydrothermal systems. Contemporaneously, complementary geophysical measurements (including down-hole temperature and pressure, discharge rates, thermal imaging, water chemistry, and video) were also collected. Located on the western flanks of the Andes Mountains at an elevation of 4200m, El Tatio is the third largest geyser field in the world. Its non-pristine condition makes it an ideal location to perform minutely invasive geophysical studies. The El Jefe Geyser was chosen for its easily accessible conduit and extremely periodic eruption cycle (~120s). During approximately 2 weeks of continuous recording, we recorded ~2500 nighttime eruptions which lack cultural noise from tourism. With ample data, we aim to study how the source varies spatially and temporally during each phase of the geyser's eruption cycle. We are developing a new back-projection processing technique to improve source imaging for diffuse signals. Our method was previously applied to the Sierra Negra Volcano system, which also exhibits repeating harmonic and diffuse seismic sources. We back-project correlated seismic signals from the receivers back to their sources, assuming linear source to receiver paths and a known velocity model (obtained from ambient noise tomography). We apply polarization filters to isolate individual and concurrent geyser energy associated with P and S phases. We generate 4D, time-lapsed images of the geyser source field that illustrate how the source distribution changes through the eruption cycle. We compare images for pre-eruption, co-eruption, post-eruption and quiescent periods. We use our images to assess eruption mechanics in the system (i.e. top-down vs. bottom-up) and

  18. Stress field evolution above the Peruvian flat-slab (Cordillera Blanca, northern Peru)

    NASA Astrophysics Data System (ADS)

    Margirier, A.; Audin, L.; Robert, X.; Pêcher, A.; Schwartz, S.

    2017-08-01

    In subduction settings, the tectonic regime of the overriding plate is closely related to the geometry of the subducting plate. Flat-slab segments are supposed to increase coupling at the plate interface in the Andes, resulting in an increase and eastward migration of the shortening in the overriding plate. Above the Peruvian flat-slab, a 200 km-long normal fault trend parallel to the range and delimits the western flank of the Cordillera Blanca. In a context of flat subduction, expected to produce shortening, the presence of the Cordillera Blanca normal fault (CBNF) is surprising. We performed a systematic inversion of striated fault planes in the Cordillera Blanca region to better characterize the stress field above the Peruvian flat-slab. It evidences the succession of different tectonic regimes. NE-SW extension is predominant in most of the sites indicating a regional extension. We suggest that the Peruvian flat-slab trigger extension in the Western Cordillera while the shortening migrated eastward. Finally, we propose that flat-slab segments do not increase the coupling at the trench neither the shortening in the overriding plate but only favor shortening migration backward. However, the stress field of the overriding plate arises from the evolution of plate interface properties through time due to bathymetric anomaly migration.

  19. Field Analogues of Shallow-water Hydrocarbon Seepages in the Pleistocene Argille Azzurre Formation: the Chimneys Field of Enza River, Northern Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Oppo, D.; Capozzi, R.; Dinelli, E.; Negri, A.; Montagna, P.; Picotti, V.; Scarponi, D.; Taviani, M.

    2012-12-01

    The geologically young Northern Apennines contain various natural seeps documenting a variability of reservoirs and fluids in terms of origin, age and evolution. Hydrocarbon and saline water seepages are controlled by the structures of the chain and the foredeep. In the geological record, the witness of these natural seepages are represented by authigenic carbonates. Their isotopic content allows to understand the carbon source and the processes of carbonate precipitation. The better known regional examples of Methane Derived Authigenic Carbonates (MDAC) and chemoherm build-ups, clustered in the Upper Miocene and Lower-Upper Pliocene successions, are formed in deep water (> 300 m) sediments. Occurrences in shallow water (shelf) settings have never been reported. Our case study describes the palisade chimneys field, recently exposed along the Enza riverbanks in the Northern Apennines in the Argille Azzurre Formation (blue mudstones) of Pleistocene age. The paleontological content (mainly bivalves) documents that this unit was deposited in an open marine muddy shelfal setting, in a bathymetric range of about 50-70 m, with local anoxic condition, documented by benthic foraminifer assemblages. The succession is biostratigraphically dated at the Early Pleistocene (Calabrian, nannoplancton zone MNN19e). A number of subvertical, metric-high columnar chimneys, ranging in diameter from 10 to 35 cm, in association with discontinuous planar carbonate concretions, intervening along the bedding planes, outcrop within the mudstones. Such concretions are clearly formed by the moderate cementation of the hosting pelitic sediments. The tubular concretions show central conduits running along the whole length, locally filled by sediments. The grain size within the concretions is homogeneous, both in the chimneys and planar concretions and irrespective of the bedding planes, suggesting a process of transport and homogenization prior to the cementation. Within the Enza river succession

  20. Field aging of insecticides after repeated application to a northern Thailand ultisol.

    PubMed

    Ciglasch, H; Busche, J; Amelung, W; Totrakool, S; Kaupenjohann, M

    2008-10-22

    Field aging immobilizes pollutants and reduces their toxicity, but it also boosts their accumulation and holds the risk of future release. We investigated the aging of six insecticides (water solubilities: 0.33 mg L (-1)-completely miscible) applied five times (10-day intervals) to a tropical fruit orchard under natural weather conditions. After sequential extractions of soil samples with 0.01 M CaCl 2, methanol (MeOH), and acetone/ethylacetate/water (AEW), a conventional ( K OC(app) = [ c(MeOH) + c(AEW)]/ c(CaCl 2), normalized to soil organic carbon) and a newly introduced distribution ratio (MAR = MeOH/AEW ratio; c(MeOH)/ c(AEW)) were calculated. Field half-lives of the insecticides correlated with K OC(app) but not with MAR, which might reflect that dissipation was significantly affected by abiotic processes. The extent of aging was related to hydrophobicity of the compounds and most pronounced for endosulfan (3-fold increase in K OC(app) within 84 days). For dimethoate, this increase was even steeper (5- to 10-fold within 10 days), which was, however, mostly caused by dissipation from labile pools rather than by aging. The K OC(app) of chlorpyrifos remained constant, but a significant decrease in MAR ( r = -0.78) revealed that sorption strength increased nevertheless. Results for malathion were ambiguous. Within the time frame of our study, neither K OC(app) nor MAR gave evidence for the aging of mevinphos. The different dynamics of K OC(app) and MAR for the six insecticides studied indicate that different aging mechanisms or rates, or both control the fate of the individual insecticides, which can potentially be revealed by sequential exctraction procedures.

  1. Distribution and origin of groundwater methane in the Wattenberg oil and gas field of northern Colorado.

    PubMed

    Li, Huishu; Carlson, Kenneth H

    2014-01-01

    Public concerns over potential environmental contamination associated with oil and gas well drilling and fracturing in the Wattenberg field in northeast Colorado are increasing. One of the issues of concern is the migration of oil, gas, or produced water to a groundwater aquifer resulting in contamination of drinking water. Since methane is the major component of natural gas and it can be dissolved and transported with groundwater, stray gas in aquifers has elicited attention. The initial step toward understanding the environmental impacts of oil and gas activities, such as well drilling and fracturing, is to determine the occurrence, where it is and where it came from. In this study, groundwater methane data that has been collected in response to a relatively new regulation in Colorado is analyzed. Dissolved methane was detected in 78% of groundwater wells with an average concentration of 4.0 mg/L and a range of 0-37.1 mg/L. Greater than 95% of the methane found in groundwater wells was classified as having a microbial origin, and there was minimal overlap between the C and H isotopic characterization of the produced gas and dissolved methane measured in the aquifer. Neither density of oil/gas wells nor distance to oil/gas wells had a significant impact on methane concentration suggesting other important factors were influencing methane generation and distribution. Thermogenic methane was detected in two aquifer wells indicating a potential contamination pathway from the producing formation, but microbial-origin gas was by far the predominant source of dissolved methane in the Wattenberg field.

  2. NOAA Ship Okeanos Explorer 2012 Field Season in the Northern Gulf of Mexico and U.S. Atlantic Continental Margin

    NASA Astrophysics Data System (ADS)

    Skarke, A. D.; Lobecker, E.; Malik, M.; VerPlanck, N.

    2012-12-01

    The NOAA Ship Okeanos Explorer, jointly operated by the NOAA Office of Ocean Exploration and Research and the NOAA Office of Marine and Aviation Operations, is America's only federally managed ship dedicated solely to ocean exploration. The 2012 field season was spent exploring the northern Gulf of Mexico and the U.S. Atlantic continental shelf break and slope. In the Gulf of Mexico, mapping and remotely operated vehicle operations focused on the salt domes and canyons offshore Mississippi and Louisiana, and characterized several of the hundreds of seeps that were detected in the water column backscatter data collected with the ship's Kongsberg EM 302 multibeam sonar (30 kHz) during the 2011 field season. A team of NOAA and non-NOAA partners identified priority frontier areas along the continental shelf and slope between North Carolina and Cape Cod, mapping numerous canyons selected for focused mapping exploration in partnership with the North East Fisheries Science Center, the Mid-Atlantic Regional Council on the Ocean (a state level partnership between various states including NY, NJ, DE, MD, and VA), Woods Hole Oceanographic Institution (WHOI) and Virginia Sea Grant. The 2012 mapping efforts built on data collected during the 2011 field season. Okeanos Explorer data were leveraged by NOAA Ship Henry B. Bigelow to conduct towed camera operations to ground truth multibeam backscatter data for deepwater coral habitat assessment. The Blake Ridge and Cape Fear Diapirs offshore North Carolina were a third focus of exploration operations. Seven 900 meter high cold seeps were discovered in the diapir province. Exploration incorporated WHOI's Sentry autonomous underwater vehicle and its full suite of mapping and oceanographic sensors were used to characterize six seep sites. All data collected by Okeanos Explorer are available via the NOAA public archives with metadata records within 60 to 90 days of the end of each cruise.

  3. A spectroscopic survey of X-ray-selected AGNs in the northern XMM-XXL field

    NASA Astrophysics Data System (ADS)

    Menzel, M.-L.; Merloni, A.; Georgakakis, A.; Salvato, M.; Aubourg, E.; Brandt, W. N.; Brusa, M.; Buchner, J.; Dwelly, T.; Nandra, K.; Pâris, I.; Petitjean, P.; Schwope, A.

    2016-03-01

    This paper presents a survey of X-ray-selected active galactic nuclei (AGNs) with optical spectroscopic follow-up in a ˜ 18 deg2 area of the equatorial XMM-XXL north field. A sample of 8445 point-like X-ray sources detected by XMM-Newton above a limiting flux of F_{0.5-10 keV} > 10^{-15} erg cm^{-2} s^{-1} was matched to optical (Sloan Digital Sky Survey, SDSS) and infrared (IR; WISE) counterparts. We followed up 3042 sources brighter than r = 22.5 mag with the SDSS Baryon Oscillation Spectroscopic Survey (BOSS) spectrograph. The spectra yielded a reliable redshift measurement for 2578 AGNs in the redshift range z = 0.02-5.0, with 0.5-2 keV luminosities ranging from 1039-1046 erg s- 1. This is currently the largest published spectroscopic sample of X-ray-selected AGNs in a contiguous area. The BOSS spectra of AGN candidates show a distribution of optical line widths which is clearly bimodal, allowing an efficient separation between broad- and narrow-emission line AGNs. The former dominate our sample (70 per cent) due to the relatively bright X-ray flux limit and the optical BOSS magnitude limit. We classify the narrow-emission line objects (22 per cent of the full sample) using standard optical emission line diagnostics: the majority have line ratios indicating the dominant source of ionization is the AGN. A small number (8 per cent of the full sample) exhibit the typical narrow line ratios of star-forming galaxies, or only have absorption lines in their spectra. We term the latter two classes `elusive' AGN, which would not be easy to identify correctly without their X-ray emission. We also compare X-ray (XMM-Newton), optical colour (SDSS) and and IR (WISE) AGN selections in this field. X-ray observations reveal, by far, the largest number of AGN. The overlap between the selections, which is a strong function of the imaging depth in a given band, is also remarkably small. We show using spectral stacking that a large fraction of the X-ray AGNs would not be

  4. VizieR Online Data Catalog: Northern XMM-XXL field AGN catalog (Menzel+, 2016)

    NASA Astrophysics Data System (ADS)

    Menzel, M.-L.; Merloni, A.; Georgakakis, A.; Salvato, M.; Aubourg, E.; Brandt, W. N.; Brusa, M.; Buchner, J.; Dwelly, T.; Nandra, K.; Paris, I.; Petitjean, P.; Schwope, A.

    2016-10-01

    The XMM-Newton XXL survey (XMM-XXL, PI Pierre) is a medium-depth (10ks per pointing) X-ray survey that covers a total area of 50deg2 split into two fields equal in size. In this paper, we focus on the equatorial sub-region of the XMM-XXL (XMM-XXL north), which overlaps with the SDSS-DR8 imaging survey (Aihara et al., 2011ApJS..193...29A). The XMM-XXL north observations were distributed around the area of the original 11deg2 XMM-LSS survey (Clerc et al., 2014MNRAS.444.2723C) and therefore build upon and extend that sample. The X-ray data used in this paper are primarily from the XMM-XXL and XMM-LSS surveys. We also include however, any additional XMM-Newton pointings that are contiguous to the area covered by those programmes, such as the XMM-Newton observations of the Subaru/XMM-Newton Deep Survey (SXDS; Ueda et al., 2008, Cat. J/ApJS/179/124) (1 data file).

  5. Investigation of the Galatian volcanic complex in the northern central Turkey using potential field data

    NASA Astrophysics Data System (ADS)

    Bilim, Funda

    2011-03-01

    The Galatia volcanic complex (GVC) is one of two important volcanic complexes located in central Anatolia, Turkey. The study of potential field data can yield useful information about the subsurface magnetisation and density distribution. In this paper, a study of the thermal structural setting of the GVC using the analysis and interpretation of aeromagnetic data is presented. Volcanic rocks are the main cause of the magnetic anomalies that occur in the study region. A Curie-point-depth (CPD) map was constructed using the azimuthally averaged power spectrum of aeromagnetic anomaly data that was reduced-to-the-pole transformed (RTP); the map shows high geothermal potential for the GVC. The Curie point depths vary from about 6.74 km to 16.9 km and are consistent with the results of previous geothermal studies. The GVC exhibits low CPD and high heat-flow values (>100 mW m -2). The CPD suggested that deep-seated magnetised sources continue downward up to 10 km (inside the upper crust). A horizontal gradient analytic signal (HGAS) map exhibits the images and locations of deep-seated magnetised sources. In addition, the CPD and average Moho depth (33 km, calculated from gravity anomaly data) are used to determine the presence of magnetic and non-magnetic crust in two cross sections taken from the GVC. The results presented should shed considerable light on some aspects of geothermal exploration in the GVC.

  6. Independent component analysis of geoelectric field data in the northern Nagano, Japan

    PubMed Central

    Orihara, Yoshiaki; Kamogawa, Masashi; Nagao, Toshiyasu; Uyeda, Seiya

    2009-01-01

    Simultaneous anomalous change of geoelectric field was observed on January 17, 1999 at three far-distant stations in Nagano Prefecture, Japan. Eleven days after the anomalous change, an earthquake swarm with a M4.8 main shock started at a location within the triangle formed by the three stations. This change was rectangular in shape like the VAN-type anomalous change in Greece. The anomaly could be detected because it occurred at midnight when the noise level was low. In fact, there were a few M4-class earthquakes in the area for which no preceding anomalous electric changes were observed, perhaps because the changes occurred during the noisy daytime. In this paper, we examine if it is possible to extract the signal with the size of the anomalous change on January 17, 1999 from the noisy daytime data by Independent Component Analysis. For this purpose, a simulated noise was embedded in the real daytime data which were highly influenced by not only artificial noise but also by geomagnetic disturbances and rainfall. Even when the influence of geomagnetic disturbance or rainfall was large, the anomalous change was clearly recognized at least at two stations in all cases. PMID:19907128

  7. Independent component analysis of geoelectric field data in the northern Nagano, Japan.

    PubMed

    Orihara, Yoshiaki; Kamogawa, Masashi; Nagao, Toshiyasu; Uyeda, Seiya

    2009-01-01

    Simultaneous anomalous change of geoelectric field was observed on January 17, 1999 at three far-distant stations in Nagano Prefecture, Japan. Eleven days after the anomalous change, an earthquake swarm with a M4.8 main shock started at a location within the triangle formed by the three stations. This change was rectangular in shape like the VAN-type anomalous change in Greece. The anomaly could be detected because it occurred at midnight when the noise level was low. In fact, there were a few M4-class earthquakes in the area for which no preceding anomalous electric changes were observed, perhaps because the changes occurred during the noisy daytime. In this paper, we examine if it is possible to extract the signal with the size of the anomalous change on January 17, 1999 from the noisy daytime data by Independent Component Analysis. For this purpose, a simulated noise was embedded in the real daytime data which were highly influenced by not only artificial noise but also by geomagnetic disturbances and rainfall. Even when the influence of geomagnetic disturbance or rainfall was large, the anomalous change was clearly recognized at least at two stations in all cases.

  8. Surface geology of the northern Midway-Sunset Field and adjacent Temblor Range, Kern County, California

    SciTech Connect

    Wylie, A.S. Jr.; Sturm, D.H.; Gardiner, R.L.; Mercer, M.F.

    1996-12-31

    New surface mapping at a 1:12000 scale adjacent to the 2 billion barrel Midway Sunset Field has revealed complex intraformational stratigraphy within the upper Miocene Santa Margarita Formation (Tms). Locally known as the Potter and Spellacy Formations in the subsurface, these sandstone and conglomerate heavy oil reservoirs produce the majority of Midway Sunset daily production of 164,000 barrels of oil via thermal EOR processes. The Tms consists mostly of conglomerate inserted into the Belridge Diatomite (Tmb) interval. The stratigraphically lower intervals of the Tms clearly fill deeply incised valleys or submarine canyons cut into Tmb and locally into the underlying Antelope Shale (Tma). The basal intervals of Tms; are very coarse grained, containing boulders of granitic and metamorphic rock as large as 4 meters that were derived from the Salinian block west of the San Andreas Fault. The upper intervals of Tms are more sheet-like and interbedded containing clasts less than 50 cm in length. The incised valleys have a spacing of about one mile in outcrop, with a gap located in the area of the older Republic Sandstone (Tmr). Paleocurrents from Tms regionally suggest sediment transport to the northeast. The sedimentary structures of Tms suggest deposition in deep-water conditions, probably a slope (bathyal) setting. Shelf environments should have been present to the southwest (now stripped away by erosion) and submarine-fan and basin-floor environments to the northeast.

  9. Surface geology of the northern Midway-Sunset Field and adjacent Temblor Range, Kern County, California

    SciTech Connect

    Wylie, A.S. Jr.; Sturm, D.H.; Gardiner, R.L.; Mercer, M.F. )

    1996-01-01

    New surface mapping at a 1:12000 scale adjacent to the 2 billion barrel Midway Sunset Field has revealed complex intraformational stratigraphy within the upper Miocene Santa Margarita Formation (Tms). Locally known as the Potter and Spellacy Formations in the subsurface, these sandstone and conglomerate heavy oil reservoirs produce the majority of Midway Sunset daily production of 164,000 barrels of oil via thermal EOR processes. The Tms consists mostly of conglomerate inserted into the Belridge Diatomite (Tmb) interval. The stratigraphically lower intervals of the Tms clearly fill deeply incised valleys or submarine canyons cut into Tmb and locally into the underlying Antelope Shale (Tma). The basal intervals of Tms; are very coarse grained, containing boulders of granitic and metamorphic rock as large as 4 meters that were derived from the Salinian block west of the San Andreas Fault. The upper intervals of Tms are more sheet-like and interbedded containing clasts less than 50 cm in length. The incised valleys have a spacing of about one mile in outcrop, with a gap located in the area of the older Republic Sandstone (Tmr). Paleocurrents from Tms regionally suggest sediment transport to the northeast. The sedimentary structures of Tms suggest deposition in deep-water conditions, probably a slope (bathyal) setting. Shelf environments should have been present to the southwest (now stripped away by erosion) and submarine-fan and basin-floor environments to the northeast.

  10. Optical parameters as a tool to study the microstructural evolution of carbonized anthracites during high-temperature treatment

    SciTech Connect

    Isabel Surez-Ruiz; Ana B. Garcia

    2007-09-15

    The graphitization process of two different carbonized anthracites in the temperature interval of 2000-2800 C was studied by using the optical properties of the materials prepared. These optical properties are defined by the main axes and parameters of the reflectance-indicating surface (RIS) and the anisotropy indexes (BW and oil bireflectance ratio). Two temperature segments, with the second one being a plateau, were found to occur in the evolution of the structural organization (textural anisotropy) of the materials. The variation with the temperature of the structural order of the materials as determined from X-ray diffraction and Raman crystalline parameters followed a similar tendency, thus confirming the validity of the optical properties as another indicator of the textural and structural changes occurring during anthracite high-temperature treatment. Moreover, as shown by the optical microscopic observation of the materials, crystalline aggregates, microspheres, and flake microstructures, which were previously detected in natural graphites, were developed from the dense and massive particles, with their proportion being higher in those materials with a larger degree of textural anisotropy and/or structural order. 29 refs., 4 figs., 3 tabs.

  11. Organic tissues, graphite, and hydrocarbons in host rocks of the Rum Jungle Uranium Field, northern Australia

    USGS Publications Warehouse

    Foster, C.B.; Robbins, E.I.; Bone, Y.

    1990-01-01

    The Rum Jungle Uranium field consists of at least six early Proterozoic deposits that have been mined either for uranium and/or the associated base and precious metals. Organic matter in the host rocks of the Whites Formation and Coomalie Dolomite is now predominantly graphite, consistent with the metamorphic history of these rocks. For nine samples, the mean total organic carbon content is high (3.9 wt%) and ranged from 0.33 to 10.44 wt%. Palynological extracts from the host rocks include black, filamentous, stellate (Eoastrion-like), and spherical morphotypes, which are typical of early Proterozoic microbiota. The colour, abundance, and shapes of these morphotypes reflect the thermal history, organic richness, and probable lacustrine biofacies of the host rocks. Routine analysis of rock thin sections and of palynological residues shows that mineral grains in some of the host rocks are coated with graphitized organic matter. The grain coating is presumed to result from ultimate thermal degradation of a petroleum phase that existed prior to metamorphism. Hydrocarbons are, however, still present in fluid inclusions within carbonates of the Coomalie Dolomite and lower Whites Formation. The fluid inclusions fluoresce dull orange in blue-light excitation and their hydrocarbon content is confirmed by gas chromatography of whole-rock extracts. Preliminary analysis of the oil suggests that it is migrated, and because it has escaped graphitization through metamorphism it is probably not of early Proterozoic age. The presence of live oil is consistent with fluid inclusion data that suggest subsequent, low-temperature brine migration through the rocks. The present observations support earlier suggestions that organic matter in the host formations trapped uranium to form protore. Subsequent fluid migrations probably brought additional uranium and other metals to these formations, and the organic matter provided a reducing environment for entrapment. ?? 1990.

  12. Classification of small agricultural fields using combined Landsat-8 and RapidEye imagery: case study of northern Serbia

    NASA Astrophysics Data System (ADS)

    Crnojević, Vladimir; Lugonja, Predrag; Brkljač, Branko; Brunet, Borislav

    2014-01-01

    A pixel-based cropland classification study based on the fusion of data from satellite images with different resolutions is presented. It is based on a time series of multispectral images acquired at different resolutions by different imaging instruments, Landsat-8 and RapidEye. The proposed data fusion method capabilities are explored with the aim of overcoming the shortcomings of different instruments in the particular cropland classification scenario characterized by the very small size of crop fields over the chosen agricultural region situated in the plains of Vojvodina in northern Serbia. This paper proposes a data fusion method that is successfully utilized in combination with arobust random forest classifier in improving the overall classification performance, as well as in enabling application of satellite imagery with a coarser spatial resolution in the given specific cropland classification task. The developed method effectively exploits available data and provides an improvement over the existing pixel-based classification approaches through the combination of different data sources. Another contribution of this paper is the employment of crowdsourcing in the process of reference data collection via dedicated smartphone application.

  13. Field evaluation of repellent formulations against daytime and nighttime biting mosquitoes in a tropical rainforest in northern Australia.

    PubMed

    Frances, S P; Van Dung, Nguye; Beebe, N W; Debboun, Mustapha

    2002-05-01

    Field trials to compare repellent formulations containing either picaridin or deet against rainforest mosquitoes in northern Queensland, Australia, were conducted. Three repellents were compared at night: 9.3% picaridin and 19.2% picaridin (Autan Repel and Autan Repel Army 20, respectively, Bayer, Sydney, Australia) and 35% deet in a gel (Australian Defense Force [ADF]). During the day, the following three repellents were compared: 19.2% picaridin, 20% deet in a controlled release formulation (Sawyer Controlled Release Deet), and 33% deet in a polymer formulation (U.S. Army Extended Duration Topical Insect and Arthropod Repellent [EDTIAR]). The predominant mosquito species collected was Verrallina lineata (Taylor), with smaller numbers of Ochlerotatus kochi (Donitz), Anopheles farauti s.s. Laveran, Ochlerotatus notoscriptus (Skuse), and Coquilletidia xanthogaster (Edwards). In nighttime tests, 19.2% picaridin provided >94.7% protection for at least 9 h, and ADF deet provided >95% protection for 7 h. The 9.3% picaridin formulation provided >95% protection for only 2 h, and provided 60% protection at 9 h. In daytime tests, Sawyer 20% deet provided >95% protection for 6 h, and both 19.2% picaridin and U.S. Army EDTIAR provided >95% protection for 8 h. In both nighttime and daytime tests 19.2% picaridin provided similar or better protection than deet formulations.

  14. Field Evidence of Colonisation by Holm Oak, at the Northern Margin of Its Distribution Range, during the Anthropocene Period

    PubMed Central

    Delzon, Sylvain; Urli, Morgane; Samalens, Jean-Charles; Lamy, Jean-Baptiste; Lischke, Heike; Sin, Fabrice; Zimmermann, Niklaus E.; Porté, Annabel J.

    2013-01-01

    A major unknown in the context of current climate change is the extent to which populations of slowly migrating species, such as trees, will track shifting climates. Niche modelling generally predicts substantial northward shifts of suitable habitats. There is therefore an urgent need for field-based forest observations to corroborate these extensive model simulations. We used forest inventory data providing presence/absence information from just over a century (1880–2010) for a Mediterranean species (Quercus ilex) in forests located at the northern edge of its distribution. The main goals of the study were (i) to investigate whether this species has actually spread into new areas during the Anthropocene period and (ii) to provide a direct estimation of tree migration rate. We show that Q. ilex has colonised substantial new areas over the last century. However, the maximum rate of colonisation by this species (22 to 57 m/year) was much slower than predicted by the models and necessary to follow changes in habitat suitability since 1880. Our results suggest that the rates of tree dispersion and establishment may also be too low to track shifts in bioclimatic envelopes in the future. The inclusion of contemporary, rather than historical, migration rates into models should improve our understanding of the response of species to climate change. PMID:24260391

  15. Field evidence of colonisation by Holm Oak, at the northern margin of its distribution range, during the Anthropocene period.

    PubMed

    Delzon, Sylvain; Urli, Morgane; Samalens, Jean-Charles; Lamy, Jean-Baptiste; Lischke, Heike; Sin, Fabrice; Zimmermann, Niklaus E; Porté, Annabel J

    2013-01-01

    A major unknown in the context of current climate change is the extent to which populations of slowly migrating species, such as trees, will track shifting climates. Niche modelling generally predicts substantial northward shifts of suitable habitats. There is therefore an urgent need for field-based forest observations to corroborate these extensive model simulations. We used forest inventory data providing presence/absence information from just over a century (1880-2010) for a Mediterranean species (Quercus ilex) in forests located at the northern edge of its distribution. The main goals of the study were (i) to investigate whether this species has actually spread into new areas during the Anthropocene period and (ii) to provide a direct estimation of tree migration rate. We show that Q. ilex has colonised substantial new areas over the last century. However, the maximum rate of colonisation by this species (22 to 57 m/year) was much slower than predicted by the models and necessary to follow changes in habitat suitability since 1880. Our results suggest that the rates of tree dispersion and establishment may also be too low to track shifts in bioclimatic envelopes in the future. The inclusion of contemporary, rather than historical, migration rates into models should improve our understanding of the response of species to climate change.

  16. Geochemistry of stream-sediment samples from the Santa Renia Fields and Beaver Peak quadrangles, northern Carlin Trend, Nevada

    USGS Publications Warehouse

    Theodore, Ted G.; Kotlyar, Boris B.; Berger, Vladimir I.; Moring, Barry C.; Singer, Donald A.; Edstrom, Sven A.

    1999-01-01

    A broad west-to-east increase of many metal concentrations has been found in stream sediments during a reconnaissance investigation conducted in conjunction with geologic studies in the Santa Renia Fields and Beaver Peak 7–1/2 minute quadrangles near the northern end of the Carlin trend of gold deposits in the Tuscarora Mountains. This regional increase in metal concentrations coincides with a dramatic change in landform wherein high concentrations of metals in stream sediments appear to correlate directly with areas of high elevations and steep slopes in the Beaver Peak quadrangle. Robust erosion combined with high flow rates in streams from these higher elevations are envisaged to have contributed significantly to increased metal concentrations in the stream sediments by an enhanced presence of minerals with high specific gravities and a correspondingly diminished presence of minerals with low specific gravities. Minerals with low specific gravities probably have been preferentially flushed down stream because of high transporting capacities for sediment by streams in the Beaver Peak quadrangle. In addition, the Carlin trend, a generally northwest-alignment of gold deposits in the Santa Renia Fields quadrangle, is well outlined by arsenic concentrations that include a maximum of approximately 54 parts per million. Further, a weakly developed distal-to-proximal metal zonation towards these gold deposits appears to be defined respectively in plots showing distributions of thallium, arsenic, antimony, and zinc. A broad area of high metal concentrations—including sharply elevated abundances of Ag, As, Au, Cd, Co, Cu, Mn, Ni, P, Sb, Sc, Te, V, and especially Zn—near the southeast corner of the Beaver Peak quadrangle primarily could be the result of stratiform mineralized rocks in the Ordovician Vinini Formation or Devonian Slaven Chert, or the result of a subsequent Mesozoic or Tertiary epigenetic overprint.

  17. Statistical properties of the surface velocity field in the northern Gulf of Mexico sampled by GLAD drifters

    NASA Astrophysics Data System (ADS)

    Mariano, A. J.; Ryan, E. H.; Huntley, H. S.; Laurindo, L. C.; Coelho, E.; Griffa, A.; Özgökmen, T. M.; Berta, M.; Bogucki, D.; Chen, S. S.; Curcic, M.; Drouin, K. L.; Gough, M.; Haus, B. K.; Haza, A. C.; Hogan, P.; Iskandarani, M.; Jacobs, G.; Kirwan, A. D.; Laxague, N.; Lipphardt, B.; Magaldi, M. G.; Novelli, G.; Reniers, A.; Restrepo, J. M.; Smith, C.; Valle-Levinson, A.; Wei, M.

    2016-07-01

    The Grand LAgrangian Deployment (GLAD) used multiscale sampling and GPS technology to observe time series of drifter positions with initial drifter separation of O(100 m) to O(10 km), and nominal 5 min sampling, during the summer and fall of 2012 in the northern Gulf of Mexico. Histograms of the velocity field and its statistical parameters are non-Gaussian; most are multimodal. The dominant periods for the surface velocity field are 1-2 days due to inertial oscillations, tides, and the sea breeze; 5-6 days due to wind forcing and submesoscale eddies; 9-10 days and two weeks or longer periods due to wind forcing and mesoscale variability, including the period of eddy rotation. The temporal e-folding scales of a fitted drifter velocity autocorrelation function are bimodal with time scales, 0.25-0.50 days and 0.9-1.4 days, and are the same order as the temporal e-folding scales of observed winds from nearby moored National Data Buoy Center stations. The Lagrangian integral time scales increase from coastal values of 8 h to offshore values of approximately 2 days with peak values of 3-4 days. The velocity variance is large, O>(1>) m2/s2, the surface velocity statistics are more anisotropic, and increased dispersion is observed at flow bifurcations. Horizontal diffusivity estimates are O>(103>) m2/s in coastal regions with weaker flow to O>(105>) m2/s in flow bifurcations, a strong jet, and during the passage of Hurricane Isaac. The Gulf of Mexico surface velocity statistics sampled by the GLAD drifters are a strong function of the feature sampled, topography, and wind forcing.

  18. Bentonite and anthracite in alginate-based controlled release formulations to reduce leaching of chloridazon and metribuzin in a calcareous soil.

    PubMed

    Flores Céspedes, F; Pérez García, S; Villafranca Sánchez, M; Fernández Pérez, M

    2013-08-01

    The leaching of herbicides through soil can be minimized using controlled release formulations (CRFs). In this research, bentonite and anthracite have been used as modifying agents in alginate-based CRFs prepared with chloridazon and metribuzin. These CRFs have been evaluated in a calcareous soil. The Kf and Koc values obtained from sorption experiments in soil have demonstrated a high leaching potential for both herbicides, mainly for metribuzin. Release kinetics in soil have showed that the control of release rate of chloridazon and metribuzin was possible by using bentonite and anthracite in CRFs, being this effect greater when we use anthracite as modifying sorbent. Using an empirical equation, the time taken for 50% of the active ingredient to be released (T50(soil)) was calculated. T50 values ranged between 2.88 d for metribuzin-bentonite alginate-based granules and 14.37 d for chloridazon-anthracite alginate-based granules, being the release rate higher in metribuzin CRFs than in those prepared with chloridazon, which has lower water solubility. Besides, a linear correlation between T50 values in water and soil was obtained. Mobility experiments carried out in a calcareous soil have shown that the use of CRFs reduces the presence of herbicides in the leachate compared to technical products, mainly for chloridazon. We found that one could design a right profile in the release rate of active ingredients from CRFs in each agro-environmental situation, and thus prevent the environmental pollution derived from the use of chloridazon and metribuzin.

  19. Microwave-assisted combustion synthesis of nano iron oxide/iron-coated activated carbon, anthracite, cellulose fiber, and silica, with arsenic adsorption studies

    EPA Science Inventory

    Combustion synthesis of iron oxide/iron coated carbons such as activated carbon, anthracite, cellulose fiber and silica is described. The reactions were carried out in alumina crucibles using a Panasonic kitchen microwave with inverter technology, and the reaction process was com...

  20. Optimization of regimes for the feed of highly concentrated culm-anthracite coal dust for burning in a TPP-210A boiler

    SciTech Connect

    L.V. Golyshev; G.A. Dovgoteles

    2007-05-15

    Results are presented for regime adjustment of feed systems for a TPP-210A boiler for the burning of highly concentrated culm-anthracite coal dust. As compared with nonoptimal regimes, optimal regimes of high-concentration-feed systems improve the economy of the boiler by 1.7% on average.

  1. Organic neem compounds inhibit soft-rot fungal growth and improve the strength of anthracite bricks bound with collagen and lignin for use in iron foundry cupolas.

    PubMed

    Kelsey, D J; Nieto-Delgado, C; Cannon, F S; Brennan, R A

    2015-07-01

    To examine organic neem compounds for their effective growth inhibition of saprotrophic soft-rot fungi on anthracite bricks bound with collagen and lignin for use in iron foundry cupolas as an alternative fuel source. Azadirachtin, crude neem oil (NO), and clarified neem oil extract (CNO) were combined with copper to inhibit the growth of the soft-rot fungus, Chaetomium globosum. A synergistic interaction was observed between CNO and a low dose of copper on nutrient media (two-factor anova with triplicate replication: P < 0·05). Interaction was confirmed on lab-scale collagen-lignin-anthracite briquettes by measuring their unconfined compressive (UC) strength. The effective collagen strength of the briquettes was enhanced by applying CNO to their surface prior to inoculation: the room temperature UC strength of the briquettes was 28 ± 4·6% greater when CNO (0·4 mg cm(-2) ) was surface-applied, and was 43 ± 3·0% greater when CNO plus copper (0·14 μg cm(-2) ) were surface-applied. Surface application of CNO and copper synergistically prevents fungal growth on bindered anthracite briquettes and increases their room temperature strength. This novel organic fungicidal treatment may increase the storage and performance of anthracite bricks in iron foundries, thereby saving 15-20% of the energy used in conventional coke production. © 2015 The Society for Applied Microbiology.

  2. Microwave-assisted combustion synthesis of nano iron oxide/iron-coated activated carbon, anthracite, cellulose fiber, and silica, with arsenic adsorption studies

    EPA Science Inventory

    Combustion synthesis of iron oxide/iron coated carbons such as activated carbon, anthracite, cellulose fiber and silica is described. The reactions were carried out in alumina crucibles using a Panasonic kitchen microwave with inverter technology, and the reaction process was com...

  3. The Cenozoic stress/deformation field of the Donets coal basin and Northern Azov region and its probable sources

    NASA Astrophysics Data System (ADS)

    Kopp, M.; Korchemagin, V.; Kolesnichenko, A.

    2009-04-01

    Studies of structure, development and dynamics of formation of the little-investigated Cenozoic (Alpine) deformations of the Donets Herzinic intraplate orogen (Donets Coal Basin, or Donbass) and Northern Azov region, which were accompanied by mass mesotectonic measurement, revealed traces of two independent Cenozoic orogenies: the Laramic one of the Early Alpine (Latest Cretaceous — Paleocene), and the Recent one of the Late Alpine (Neogene — Quaternary). The orogenies differ in area of manifestation and peculiarities of stress/deformation field. The first orogeny in its pure state developed only in the western Donbass and adjacent relic part of the Dnieper-Donets aulacogene where gentle folds of the Mesozoic strata of the WNW - ESE strike were formed. The folds (so-called Izyum-Kramatorsk structural unit) are sharply overprinted by the Eocene beds and confined to salt diapirs gradually uplifting from the Devonian. According the mesotectonic data, in the post-Cretaceous time they however developed under slight transversal compression with some horizontal shear. The Laramic movements occurred also to the east where they together with the Recent ones participated in formation of the Severodonetskij and Persianovskij border reverse faults of the Donbass. However, as a whole the Recent orogeny developed independently and far to the east of the Laramic one. The Donets-North Azov neotectonic swell which appeared at that time occupies not only the eastern Donets intraplate orogen arised from the Dnieper-Donets aulacogene but strongly crosses the southern aulacogene border extending far into the Ukrainian shield. The different areas of the Laramic and Recent orogenic movements in the Donbass suggest that they raised from different sources. The eastern distribution of the Late Alpine deformation and its more intense manifestation (the well noticeable neotectonic uplift as well as the extension outside the aulacogene and the activization of the Ukrainian shield basement

  4. Prehistoric Agriculture and Soil Fertility on Lava Flows in Northern Arizona, USA: Results from the San Francisco Volcanic Field REU

    NASA Astrophysics Data System (ADS)

    Broadman, E.; Anderson, K. C.

    2013-12-01

    The San Francisco Volcanic Field in northern Arizona is home to ~600 cinder cones, the youngest of which is Sunset Crater (erupted ~AD 1100). This study documents trends in available phosphate and nitrate content with time, testing whether lowered soil pH from the addition of Sunset cinders increased soil fertility and became a factor in Anasazi agricultural success. Soil fertility is examined both before and after Sunset's eruption in soils of different ages that have developed from eolian deposition on top of lava flows. An increase in phosphate and nitrate levels following acidification would suggest that the presence of Sunset cinders brought the soils to the optimal pH for mobilization of these nutrients. The combined effects of the cinder layer retaining nutrients and water, wetter climates, and increases in phosphate and nitrate (both limiting nutrients for plant growth), would have contributed to Anasazi agricultural success after Sunset's eruption. Samples for this study were taken from eolian-derived soils of different ages atop lava flows in the San Francisco Volcanic Field. OSL data from these soils on Strawberry and SP Craters' lava flows yielded age estimates of ~12.3 ka (Strawberry) and ~32.7 ka (SP), on which a soil chronosequence was based. Results from the chronosequence supported these OSL ages, indicating that soils on the SP flow are older than those on the Strawberry flow. Field descriptions, Harden Development Indices, particle size analysis, and nutrient content analysis were used for this aspect of the project. An experimental acid wash method will be used to simulate the addition of Sunset's acidic cinders, and will yield data for phosphate and nitrate content after Sunset erupted. Preliminary results indicate that phosphate and nitrate accumulate in upper, eolian-derived horizons (Av, Bw) and in more deeply buried carbonate horizons (Bk). Higher concentrations of phosphate and nitrate were found in older (SP) soils than younger

  5. Extensive FE-SEM/EDS, HR-TEM/EDS and ToF-SIMS studies of micron- to nano-particles in anthracite fly ash.

    PubMed

    Ribeiro, Joana; DaBoit, Kátia; Flores, Deolinda; Kronbauer, Marcio A; Silva, Luis F O

    2013-05-01

    The generation of anthropogenic carbonaceous matter and mixed crystalline/amorphous mineral ultrafine/nano-particles in the 1 to 100 nm size range by worldwide coal power plants represents serious environmental problems due to their potential hazards. Coal fly ash (CFA) that resulted from anthracite combustion in a Portuguese thermal power plant was studied in this work. The physico-chemical characterization of ultrafine/nano-particles present in the CFA samples and their interaction with environment are the aim of this study. The methodologies applied for this work were field emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy with energy dispersive X-ray spectroscopy (HR-TEM/EDS) and time of flight secondary ion mass spectrometry (ToF-SIMS). Some hazardous volatile elements, C, N, S and Hg contents were also determined in the studied samples. Generally, the CFA samples comprise carbonaceous, glassy and metallic solid spheres with some containing mixed amorphous/crystalline phases. The EDS analysis coupled with the FE-SEM and HR-TEM observations of the fly ash particles with 100 to 0.1 nm demonstrates that these materials contain a small but significant proportion of encapsulated HVEs. In addition, the presence of abundant multi-walled carbon nanotubes (MWCNTs) and amorphous carbon particles, both containing hazardous volatile elements (HVEs), was also evidenced by the FE-SEM/EDS and HR-TEM/EDS analysis. A wide range of organic and inorganic compounds was determined by chemical maps obtained in ToF-SIMS analysis.

  6. Hg and Se capture and fly ash carbons from combustion of complex pulverized feed blends mainly of anthracitic coal rank in Spanish power plants

    SciTech Connect

    I. Surez-Ruiz; J.C. Hower; G.A. Thomas

    2007-01-15

    In this work, the petrology and chemistry of fly ashes produced in a Spanish power plant from the combustion of complex pulverized feed blends made up of anthracitic/meta-anthracitic coals, petroleum, and natural coke are investigated. It was found that the behavior of fly ash carbons derived from anthracitic coals follows relatively similar patterns to those established for the carbons from the combustion of bituminous coals. Fly ashes were sampled in eight hoppers from two electrostatic precipitator (ESP) rows. The characterization of the raw ashes and their five sieved fractions (from {gt}150 to {lt}25 {mu}m) showed that glassy material, quartz, oxides, and spinels in different proportions are the main inorganic components. As for the organic fraction, the dominant fly ash carbons are anisotropic carbons, mainly unburned carbons derived from anthracitic vitrinite. The concentration of Se and Hg increased in ashes of the second ESP row, this increase being related to the higher proportion of anisotropic unburned carbons, particularly those largely derived from anthracitic vitrinite in the cooler ashes of the ESP (second row) and also related to the decrease in the flue gas temperature. This suggests that the flue gas temperature plays a major role in the concentration of mercury for similar ratios of unburned carbons. It was also found that Hg is highly concentrated in the medium-coarser fractions of the fly ashes ({gt} 45 {mu}m), there being a positive relationship between the amount of these carbons, which are apparently little modified during the combustion process, in the medium-coarse fractions of the ashes and the Hg retention. According to the results obtained, further research on this type of fly ash could be highly productive. 28 refs., 10 figs., 8 tabs.

  7. High prevalence of mutation in the Plasmodium falciparum dhfr and dhps genes in field isolates from Sabah, Northern Borneo.

    PubMed

    Abdullah, Noor Rain; Norahmad, Nor Azrina; Jelip, Jenarun; Sulaiman, Lokman Hakim; Mohd Sidek, Hasidah; Ismail, Zakiah; Noedl, Harald

    2013-06-12

    Sulphadoxine-pyrimethamine (SP) has been in use for the treatment of uncomplicated falciparum malaria in Malaysia since the 1970s and is still widely employed in spite of widespread clinical resistance. Resistance to SP is known to be mediated by mutations in the pfdhfr and pfdhps genes. The aim of the present study was to investigate the distribution of pfdhfr and pfdhps gene polymorphism in Plasmodium falciparum field isolates from Kalabakan, Sabah, in northern Borneo. A total number of 619 individuals were screened from 23 study sites of which 31 were positive for P. falciparum. Analysis of restriction fragment length polymorphisms (RFLP) was used to identify polymorphism in the pfdhfr and pfdhps genes at positions 16, 51, 59, 108, 164 and 437, 540, 581, respectively. All samples had at least one mutation in each of the genes associated with drug resistance. The prevalence of pfdhfr 59arg, 164leu and 108asn were 100%, 80.65% and 58.06%, respectively. Pfdhps mutants 437gly and 581gly accounted for 100% and 74.19% respectively. In pfdhfr, the most common mutant genotypes were combination 59arg + 164leu (22.58%) and 59arg + 108asn + 164leu (51.61%). In pfdhps the most common genotype was 437gly + 581gly (74.19%). One individual (3.22%) harboured parasites with four pfdhfr (16 val + 59arg + 108asn + 164leu) and two pfdhps (437gly + 581gly) mutations. The highest quintuple pfdhfr/pfdhps (41.94%) was three pfdhfr (59arg + 108asn + 164gly) and two pfdhps (437gly + 581gly). The data suggest a high prevalence of genetic variations conferring resistance to SP which can predict treatment failure before becoming clinically evident. In areas like this, the use of SP may no longer be indicated.

  8. Stress field variations in the Swiss Alps and the northern Alpine foreland derived from inversion of fault plane solutions

    USGS Publications Warehouse

    Kastrup, U.; Zoback, M.L.; Deichmann, N.; Evans, Kenneth F.; Giardini, D.; Michael, A.J.

    2004-01-01

    This study is devoted to a systematic analysis of the state of stress of the central European Alps and northern Alpine foreland in Switzerland based on focal mechanisms of 138 earthquakes with magnitudes between 1 and 5. The most robust feature of the results is that the azimuth of the minimum compressive stress, S3, is generally well constrained for all data subsets and always lies in the NE quadrant. However, within this quadrant, the orientation of S3 changes systematically both along the structural strike of the Alpine chain and across it. The variation in stress along the mountain belt from NE to SW involves a progressive, counterclockwise rotation of S3 and is most clear in the foreland, where it amounts to 45??-50??. This pattern of rotation is compatible with the disturbance to the stress field expected from the indentation of the Adriatic Block into the central European Plate, possibly together with buoyancy forces arising from the strongly arcuate structure of the Moho to the immediate west of our study area. Across the Alps, the variation in azimuth of S3 is defined by a progressive, counterclockwise rotation of about 45?? from the foreland in the north across the Helvetic domain to the Penninic nappes in the south and is accompanied by a change from a slight predominance of strike-slip mechanisms in the foreland to a strong predominance of normal faulting in the high parts of the Alps. The observed rotation can be explained by the perturbation of the large-scale regional stress by a local uniaxial deviatoric tension with a magnitude similar to that of the regional differential stress and with an orientation perpendicular to the strike of the Alpine belt. The tensile nature and orientation of this stress is consistent with the "spreading" stress expected from lateral density changes due to a crustal root beneath the Alps. Copyright 2004 by the American Geophysical Union.

  9. Health risk assessment from contaminated foodstuffs: a field study in chromite mining-affected areas northern Pakistan.

    PubMed

    Nawab, Javed; Li, Gang; Khan, Sardar; Sher, Hassan; Aamir, Muhammad; Shamshad, Isha; Khan, Anwarzeb; Khan, Muhammad Amjad

    2016-06-01

    This study aimed to investigate the potential health risk associated with toxic metals in contaminated foodstuffs (fruits, vegetables, and cereals) collected from various agriculture fields present in chromite mining-affected areas of mafic and ultramafic terrains (northern Pakistan). The concentrations of Cr, Ni, Zn, Cd, and Pb were quantified in both soil and food samples. The soil samples were highly contaminated with Cr (320 mg/kg), Ni (108 mg/kg), and Cd (2.55 mg/kg), which exceeded their respective safe limits set by FAO/WHO. Heavy metal concentrations in soil were found in the order of Cr>Ni>Pb>Zn>Cd and showed significantly (p < 0.001) higher concentrations as compared to reference soil. The integrated pollution load index (PLI) value was observed greater than three indicating high level of contamination in the study area. The concentrations of Cr (1.80-6.99 mg/kg) and Cd (0.21-0.90 mg/kg) in foodstuffs exceeded their safe limits, while Zn, Pb, and Ni concentrations were observed within their safe limits. In all foodstuffs, the selected heavy metal concentrations were accumulated significantly (p < 0.001) higher as compared to the reference, while some heavy metals were observed higher but not significant like Zn in pear, persimmon, white mulberry, and date-plum; Cd in pear, fig and white mulberry; and Pb in walnut, fig, and pumpkin. The health risk assessment revealed no potential risk for both adults and children for the majority of heavy metals, except Cd, which showed health risk index (HRI) >1 for children and can pose potential health threats for local inhabitants. Graphical Abstract Heavy metals released from chromite mining lead to soil and foodstuff contamination and human health risk.

  10. High resistance to pyrethroid insecticides associated with ineffective field treatments in Triatoma infestans (Hemiptera: Reduviidae) from Northern Argentina.

    PubMed

    Picollo, María Inés; Vassena, Claudia; Santo Orihuela, Pablo; Barrios, Silvia; Zaidemberg, Mario; Zerba, Eduardo

    2005-07-01

    Field populations of Triatoma infestans Klug were collected during 2002 from four villages in northern Argentina (El Chorro, La Toma, El Sauzal, and Salvador Mazza), after application of deltamethrin and other pyrethroids was ineffective. High levels of resistance to the pyrethroid insecticides deltamethrin, beta-cypermethrin, beta-cyfluthrin, and lambda-cyhalothrin were detected in all of the evaluated populations. The resistance ratio to pyrethroids determined by topical application ranged from 50.5 (deltamethrin, El Sauzal) to 667.6 (beta-cyfluthrin, Salvador Mazza). None of the pyrethroid-resistant insects was resistant to the organophosphorus insecticide fenitrothion. Topical application of piperonyl butoxide to the most deltamethrin-resistant population (Salvador Mazza) led to slight reduction in levels of resistance. Activity of P450 monooxygenase, measured in individual insects through ethoxycoumarine-O-deethylase, showed a slight but noticeable difference in the distribution of activities between susceptible and resistant populations. The total percentage of insects below 0.48 pmol of 7-OH coumarine/min/ insect was 36.4 for Salvador Mazza population and 64.3 pmol of 7-OH coumarine/min/insect for CIPEIN strain. Whereas a low level of resistance to deltamethrin was previously related to monooxygenase activity in T. infestans, the high levels of resistance shown by these populations seem to involve monooxygenase in combination with other resistance mechanisms, for example, insensitivity of nervous membrane. Research on T. infestans resistance is in progress to improve Chagas vector control programs in Latin America and to implement resistance management strategies.

  11. Field-mapping and petrographic analysis of volcanoes surrounding the Lake Natron Homo sapiens footprint site, northern Tanzania

    NASA Astrophysics Data System (ADS)

    Hewitt, S. M.; Zimmer, B.; Liutkus, C.; Carmichael, S. K.; McGinnis, K.

    2010-12-01

    The Lake Natron Homo sapiens footprint site is located in northern Tanzania along the East African Rift escarpment. The site is positioned south of Lake Natron within an ephemeral channel of the Engare Sero River. The hominid footprints are preserved in a tuff, which originated from one of the volcanic centers surrounding the site. Two large volcanoes in the surrounding region, including the active carbonatite producing Oldoinyo L’engai and the now extinct Kerimasi are possible sources. This area also contains over 30 smaller tuff cones and tuff rings that have been poorly mapped and not analyzed in detail. The site is significant as it is the oldest modern human trackway in East Africa and one of the largest collections of hominid footprints in the world. Determining the source of the footprinted volcanic ash requires detailed field mapping, and both petrographic and geochemical analyses. Extensive field-mapping of the region revealed multiple regional beds that stratigraphically overlay the footprinted layer. Age dating as well as geochemical analysis is being conducted to relate these beds to the footprinted layer. Field-mapping showed that the footprinted tuff is over 35 cm thick, suggesting a large, sustained eruption. The bulk of the tuff cones examined in the field visibly varied in composition to the footprinted tuff and, based on proximity to the footprint site, are too small to produce the requisite volume of ash. Field analysis of samples collected from Oldoinyo L’engai reveal the most similar mineral assemblages to the footprinted layer, and the large volcano provides a source substantial enough to create a thick ash bed 10 km north of the summit. Preliminary research reveals that the footprinted tuff is a phonolite, characterized by silica depletion and the presence of sanidine, augite, and annite with interstitial calcite. XRD analysis of samples collected from Oldoinyo L’engai reveal a nepheline-rich phonolite with zeolites (ie. phillipsite

  12. Dissimilar responses of larch stands in northern Siberia to increasing temperatures-a field and simulation based study.

    PubMed

    Wieczorek, Mareike; Kruse, Stefan; Epp, Laura S; Kolmogorov, Alexei; Nikolaev, Anatoly N; Heinrich, Ingo; Jeltsch, Florian; Pestryakova, Lyudmila A; Zibulski, Romy; Herzschuh, Ulrike

    2017-09-01

    Arctic and alpine treelines worldwide differ in their reactions to climate change. A northward advance of or densification within the treeline ecotone will likely influence climate-vegetation feedback mechanisms. In our study, which was conducted in the Taimyr Depression in the North Siberian Lowlands, w present a combined field- and model-based approach helping us to better understand the population processes involved in the responses of the whole treeline ecotone, spanning from closed forest to single-tree tundra, to climate warming. Using information on stand structure, tree age, and seed quality and quantity from seven sites, we investigate effects of intra-specific competition and seed availability on the specific impact of recent climate warming on larch stands. Field data show that tree density is highest in the forest-tundra, and average tree size decreases from closed forest to single-tree tundra. Age-structure analyses indicate that the trees in the closed forest and forest-tundra have been present for at least ~240 yr. At all sites except the most southerly ones, past establishment is positively correlated with regional temperature increase. In the single-tree tundra, however, a change in growth form from krummholz to erect trees, beginning ~130 yr ago, rather than establishment date has been recorded. Seed mass decreases from south to north, while seed quantity increases. Simulations with LAVESI (Larix Vegetation Simulator) further suggest that relative density changes strongly in response to a warming signal in the forest-tundra while intra-specific competition limits densification in the closed forest and seed limitation hinders densification in the single-tree tundra. We find striking differences in strength and timing of responses to recent climate warming. While forest-tundra stands recently densified, recruitment is almost non-existent at the southern and northern end of the ecotone due to autecological processes. Palaeo-treelines may therefore

  13. Style of Plate Spreading Derived from the 2008-2014 Velocity Field Across the Northern Volcanic Zone of Iceland

    NASA Astrophysics Data System (ADS)

    Drouin, V.; Sigmundsson, F.; Hreinsdottir, S.; Ofeigsson, B.; Sturkell, E.; Einarsson, P.

    2015-12-01

    The Northern Volcanic Zone (NVZ) of Iceland is a subaerial part of the divergent boundary between the North-American and Eurasian Plates. At this latitude, the full spreading between the plates is accommodated by the NVZ. We derived the plate boundary velocity field from GPS campaign and continuous measurements between 2008 and 2014, a time period free of any magma intrusion. Average velocities were estimated in the ITRF08 reference frame. The overall extension is consistent with 18 mm/yr in the 104°N direction spreading, in accordance with the MORVEL2010 plate motion model. We find that a 40km-wide band along the plate boundary accommodates about 75% of the full plate velocities. Within this zone, the average strain rate is approximately 0.35 μstrain/yr. The deformation field and the strain rate are, however, much affected by other sources of deformations in the NVZ. These include magmatic sources at the most active volcanic centers, glacial rebound near the ice-caps and geothermal power-plant water extraction. Magmatic sources include a shallow magma chamber deflation under Askja caldera, as well as under Þeistareykir and eventual deep magma inflation north of Krafla volcano. Vatnajökull ice cap melting causes large uplift and outward displacements in the southern part of the NVZ. The two geothermal power-plants near Krafla are inducing local deflations. Our GPS velocities show a 35° change in the direction of the plate boundary axis north of Askja volcano that we infer to be linked to the geometric arrangement of volcanic systems within the NVZ.We use a simple arctangent model to describe the plate spreading to provide constraints on the location and the locking depth of the spreading axis. For that purpose we divided the area in short overlapping segments having the same amount of GPS points along the plate spreading direction and inverted for the location of the center of the spreading axis and locking depth. With this simple model we can account for most

  14. Removal of microcystin-LR from spiked water using either activated carbon or anthracite as filter material.

    PubMed

    Drogui, Patrick; Daghrir, Rimeh; Simard, Marie-Christine; Sauvageau, Christine; Blais, Jean François

    2012-01-01

    The occurrence of cyanobacterial toxins (blue-green algae) in drinking water sources is a big concern for human health. Removal of microcystin-LR (MC-LR) from drinking water was evaluated at the laboratory pilot scale using either granular activated carbon (GAC) or powdered activated carbon (PAC) and compared with the treatment using anthracite as filter material. Virgin GAC was more effective at removing MC-LR (initial concentration ranging from 9 to 47 microg L(-1)) to reach the World Health Organization recommended level (1.0 microg L(-1)). When the GAC filter was colonized by bacteria, the filter became less effective at removing MC-LR owing to competitive reactions occurring between protein adsorption (released by bacteria) and MC-LR adsorption. Using PAC, the concentration of MC-LR decreased from 22 to 3 microg L(-1) (removal of 86% of MC-LR) by the addition of 100 mg PAC L(-1).

  15. The impact of episodic coal mine drainage pollution on benthic macroinvertebrates in streams in the Anthracite region of Pennsylvania.

    PubMed

    Maccausland, A; McTammany, M E

    2007-09-01

    Episodic coal mine drainage, caused by fluctuations in mine discharges relative to stream flow, has devastating effects on aquatic macroinvertebrate communities. Seven stream reaches in the Anthracite region of Pennsylvania were identified as chronically, episodically or not impaired by mine drainage, and sampled seasonally for 1 year to determine the effect of episodic mine drainage on macroinvertebrates. Specific conductance fluctuated seasonally in episodic sites; it was lower in winter when discharge increased and higher in summer when discharges decreased and mine drainage made up a larger proportion of stream flow. Although we hypothesized that episodic streams would have higher macroinvertebrate richness than chronic streams, comparisons showed no differences in richness between treatments. Episodic pollution may result from undersized or poorly maintained passive treatment systems; therefore, intensive macroinvertebrate monitoring may be needed to identify streams being affected by episodic mine drainage because macroinvertebrate richness may be sensitive to water quality fluctuations.

  16. Demineralisation of semi-anthracite char with molten salts/HCl. Effects on the porous texture and reactivity in air

    NASA Astrophysics Data System (ADS)

    Alfaro-Domínguez, M.; Higes-Rolando, F. J.; Rojas-Cervantes, M. L.; Gómez-Serrano, V.

    2006-06-01

    The effects of chemical heat treatments of a semi-anthracite char (AC) on textural properties and reactivity in air of the material are investigated. The starting char was first treated with a mixture of LiCl/KCl or LiCl/KCl/CaO at 743, 873 or 1173 K and the products obtained were then washed thoroughly with distilled water. A small fraction of these samples were treated with 10 -3 M HCl solution. Valuable information on textural modifications produced in the material was derived from the adsorption isotherms for CO 2 at 273 K. The reactivity tests were carried out at 808, 823 and 823 K. The microporosity developed and the reactivity in air increased in the partially demineralised products. The former effect was stronger for the LiCl/KCl/CaO-treated samples and the latter for a larger number of the LiCl/KCl-treated samples.

  17. Enhanced removal of sulfonamide antibiotics by KOH-activated anthracite coal: Batch and fixed-bed studies.

    PubMed

    Zuo, Linzi; Ai, Jing; Fu, Heyun; Chen, Wei; Zheng, Shourong; Xu, Zhaoyi; Zhu, Dongqiang

    2016-04-01

    The presence of sulfonamide antibiotics in aquatic environments poses potential risks to human health and ecosystems. In the present study, a highly porous activated carbon was prepared by KOH activation of an anthracite coal (Anth-KOH), and its adsorption properties toward two sulfonamides (sulfamethoxazole and sulfapyridine) and three smaller-sized monoaromatics (phenol, 4-nitrophenol and 1,3-dinitrobenzene) were examined in both batch and fixed-bed adsorption experiments to probe the interplay between adsorbate molecular size and adsorbent pore structure. A commercial powder microporous activated carbon (PAC) and a commercial mesoporous carbon (CMK-3) possessing distinct pore properties were included as comparative adsorbents. Among the three adsorbents Anth-KOH exhibited the largest adsorption capacities for all test adsorbates (especially the two sulfonamides) in both batch mode and fixed-bed mode. After being normalized by the adsorbent surface area, the batch adsorption isotherms of sulfonamides on PAC and Anth-KOH were displaced upward relative to the isotherms on CMK-3, likely due to the micropore-filling effect facilitated by the microporosity of adsorbents. In the fixed-bed mode, the surface area-normalized adsorption capacities of Anth-KOH for sulfonamides were close to that of CMK-3, and higher than that of PAC. The irregular, closed micropores of PAC might impede the diffusion of the relatively large-sized sulfonamide molecules and in turn led to lowered fixed-bed adsorption capacities. The overall superior adsorption of sulfonamides on Anth-KOH can be attributed to its large specific surface area (2514 m(2)/g), high pore volume (1.23 cm(3)/g) and large micropore sizes (centered at 2.0 nm). These findings imply that KOH-activated anthracite coal is a promising adsorbent for the removal of sulfonamide antibiotics from aqueous solution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Detailed Observations and Sampling of the Sea Cliff Hydrothermal Field (GR-14) on the Northern Gorda Ridge

    NASA Astrophysics Data System (ADS)

    McClain, J. S.; Zierenberg, R.; Clague, D. A.; Von Damm, K. L.; Davis, A.; Goffredi, S.; Mayer, N.; Orphan, V.; Olsen, E.; Ross, S. L.

    2001-12-01

    During the summer of 2000, on a research cruise of the MBARI research ship, Western Flyer, we deployed the ROV Tiburon for a series of dives at the Sea Cliff Hydrothermal site on the northern Gorda Ridge. The Sea Cliff site is near the top of a terrace on the west facing rift valley wall (fault), about 300 meters above, and 3 km east of the ridge axis. The 1996 Gorda Ridge eruption occurred on axis in the region west and south of the vent site. The vents were first predicted on the basis of water column anomalies and seafloor structure, and the field was discovered in 1988 during dives of the Sea Cliff submersible. In 2000, we made 4 dives at the site and collected a suite of rock and vent fluid samples. The high temperature water vents from as many as 10 individual chimneys. Measured vent temperatures at several of the chimneys fall in a narrow range of around 304\\deg C. The chimneys are arrayed along two low ridges that are oriented roughly perpendicular to the strike of the rift valley. Venting fluids have low salinity indicating subsurface phase separation. The waters are isotopically enriched (\\delta 18O = 1.9%), suggesting extensive water-rock interaction. The chimneys themselves are primarily anhydrite and a pale green Mg-rich clay with minor amounts of amorphous silica, pyrrhotite, wurtzite, and isocubanite. The chimneys are delicate and are surrounded by aprons (5 -10 m) of collapsed chimney material. As a result, no macro fauna were observed colonizing the high temperature vents. Silica-rich hydrothermal crust and talus cover the fault slope. A broad region of diffuse venting surrounds the active chimneys and locally supports a rich biological community that includes blue ciliate mats near the vents, that give way to tube worm fields and low tube worm mounds formed on massive barite. The Sea Cliff Hydrothermal site is unusual in that it lies off axis and above the rift valley floor. Faulting must play a role in its location and perhaps geometry, and the

  19. Eruptive and depositional characteristics of the Loolmurwak and Eledoi maar volcanoes, Lake Natron - Engaruka monogenetic volcanic field, northern Tanzania

    NASA Astrophysics Data System (ADS)

    Berghuijs, J. F.; Mattsson, H. B.; Bosshard, S. A.

    2012-04-01

    The Eledoi and Loolmurwak maars form two of the largest craters within the Lake Natron - Engaruka monogenetic volcanic field (northern Tanzania), an area consisting of approximately 200 vents scattered between four large central volcanoes. We here describe depositional characteristics of the two maars, as observed in the field, and present preliminary findings on the petrographic textures which can provide insights into the eruption dynamics. Most maar volcanoes are considered to be the result of explosive phreatomagmatic volcanic eruptions (in which ascending magma interacts with external water). However, our field observations indicate that neither Loolmurwak nor Eledoi provides clear evidence of wet eruption or deposition. The overall arid climate in the area, in combination with the higher elevation of these maars with respect to their surroundings, makes the availability of external water, necessary to drive a phreatomagmatic eruption, questionable. Features indicative of phreatomagmatism, such as accretionary lapilli, vesiculated tuffs or plastering against objects, were not observed. Rather, most observations points toward dry eruption modes for these eruptions. The ejecta ring of Eledoi is strongly asymmetrical, with the finer deposit fractions concentrated on its NW side, suggesting a dry eruption column that allowed effective eolian segregation of differently sized pyroclasts during deposition. Subspherical melt blobs, cored with single olivine, clinopyroxene and phlogopite crystals that reach up to 11 cm in diameter, occur abundantly at Loolmurwak. Many of these melt blobs show slight flattening parallel to the bedding plane, which indicates that they were emplaced as molten droplets. The abundance of large phlogopite phenocrysts in the Loolmurwak deposits points towards a volatile-rich magma. The occurrence of mantle xenoliths, 20-30 cm in diameter, implies that the magma traveled from the upper mantle to the surface in less than two days. The rapid

  20. Secular variation of the geomagnetic field over the past 4000 years recorded in the lavas and pyroclastics of the Northern Group of Kamchatka volcanoes: New data

    NASA Astrophysics Data System (ADS)

    Latyshev, A. V.; Kushlevich, D. O.; Ponomareva, V. V.; Pevzner, M. M.; Fedyukin, I. V.

    2017-09-01

    New paleomagnetic determinations satisfying the up-to-date methodical and instrumental standards of paleomagnetic studies are obtained from the lava flows and volcanic ash of the Northern Group of Kamchatka volcanoes. In the past 4000 years, 12 stratigraphic levels with tephrostratigraphic ages are explored. The obtained directions of the geomagnetic field fill a gap in the data on the secular variation for northeastern Asia and can be used for developing global models. Besides, a promising outlook for the use of the variations of the geomagnetic field for the regional correlation of volcanic events is demonstrated.

  1. Northern Pintail

    USGS Publications Warehouse

    Clark, Robert G.; Fleskes, Joseph P.; Guyn, Karla L.; Haukos, David A.; Austin, Jane E.; Miller, Michael R.

    2014-01-01

    This medium-sized dabbling duck of slender, elegant lines and conservative plumage coloration is circumpolar in distribution and abundant in North America, with core nesting habitat in Alaska and the Prairie Pothole Region of southern Canada and the northern Great Plains. Breeders favor shallow wetlands interspersed throughout prairie grasslands or arctic tundra. An early fall migrant, the species arrives on wintering areas beginning in August, after wing molt, often forming large roosting and feeding flocks on open, shallow wetlands and flooded agricultural fields. The birds consume grains, marsh plant seeds, and aquatic invertebrates throughout fall and winter.Northern Pintails are among the earliest nesting ducks in North America, beginning shortly after ice-out in many northern areas. Individuals form new pair bonds each winter but are highly promiscuous during the nesting season, with mated and unmated males often involved in vigorous, acrobatic Pursuit Flights. Annual nest success and productivity vary with water conditions, predation, and weather. Females build nests on the ground, often far from water. Only the female incubates; her mate leaves shortly after incubation begins. Ducklings hatch together in one day, follow the female to water after a day in the nest, and fledge by July or August. Adults and ducklings consume mainly aquatic invertebrates during the breeding season.Predators and farming operations destroy many thousands of Northern Pintail nests annually; farming has also greatly reduced the amount of quality nesting cover available. Winter habitats are threatened by water shortages, agricultural development, contamination, and urbanization. Periods of extended drought in prairie nesting regions have caused dramatic population declines, usually followed by periods of recovery. Over the long term, however, the continental population of Northern Pintails has declined significantly from 6 million birds in the early 1970s to less than 3 million in

  2. Channel response to tectonic forcing: field analysis of stream morphology and hydrology in the Mendocino triple junction region, northern California

    NASA Astrophysics Data System (ADS)

    Snyder, Noah P.; Whipple, Kelin X.; Tucker, Gregory E.; Merritts, Dorothy J.

    2003-07-01

    An empirical calibration of the shear stress model for bedrock incision is presented, using field and hydrologic data from a series of small, coastal drainage basins near the Mendocino triple junction in northern California. Previous work comparing basins from the high uplift zone (HUZ, uplift rates around 4 mm/year) to ones in the low uplift zone (LUZ, ˜0.5 mm/year) indicates that the HUZ channels are about twice as steep for a given drainage area. This observation suggests that incision processes are more effective in the HUZ. It motivates a detailed field study of channel morphology in the differing tectonic settings to test whether various factors that are hypothesized to influence incision rates (discharge, channel width, lithology, sediment load) change in response to uplift or otherwise differ between the HUZ and LUZ. Analysis of regional stream gaging data for mean annual discharge and individual floods yields a linear relationship between discharge and drainage area. Increased orographic precipitation in the HUZ accounts for about a twofold increase in discharge in this area, corresponding to an assumed increase in the erosional efficiency of the streams. Field measurements of channel width indicate a power-law relationship between width and drainage area with an exponent of ˜0.4 and no significant change in width between the uplift rate zones, although interpretation is hampered by a difference in land use between the zones. The HUZ channel width dataset reveals a scaling break interpreted to be the transition between colluvial- and fluvial-dominated incision processes. Assessments of lithologic resistance using a Schmidt hammer and joint surveys show that the rocks of the study area should be fairly similar in their susceptibility to erosion. The HUZ channels generally have more exposed bedrock than those in the LUZ, which is consistent with protection by sediment cover inhibiting incision in the LUZ. However, this difference is likely the result of a

  3. Geology of the Right Stepover region between the Rodgers Creek, Healdsburg, and Maacama faults, northern San Francisco Bay region: a contribution to Northern California Geological Society Field Trip Guide, June 6-8, 2003

    USGS Publications Warehouse

    McLaughlin, Robert J.; Sarna-Wojcicki, Andrei

    2003-01-01

    This Open file report was written as part of a two-day field trip on June 7 and 8, 2003, conducted for the Northern California Geological Society. The first day of this field trip (June 7) was led by McLaughlin and Sarna-Wojcicki in the area of the right- step between the Rodgers Creek- Healdsburg fault zone and the Maacama fault. The second day of the trip (June 8), was led by David Wagner of the California Geological Survey and students having recently completed MS theses at San Jose State University (James Allen) and San Francisco State University (Carrie Randolph-Loar), as well as a student from San Francisco State University whose MS thesis was in progress in June 2003 (Eric Ford). The second day covered the Rodgers Creek fault zone and related faults of the Petaluma Valley area (the Tolay and Petaluma Valley fault zones).

  4. Host choice of Phlebotomus orientalis (Diptera: Psychodidae) in animal baited experiments: a field study in Tahtay Adiyabo district, northern Ethiopia.

    PubMed

    Gebresilassie, Araya; Yared, Solomon; Aklilu, Essayas; Kirstein, Oscar David; Moncaz, Aviad; Tekie, Habte; Balkew, Meshesha; Warburg, Alon; Hailu, Asrat; Gebre-Michael, Teshome

    2015-03-31

    Host choice and feeding success of sand fly vectors of visceral leishmaniasis (VL) are important factors in understanding the epidemiology and for developing efficient control strategies. The aim of the present study was to determine the host preference of Phlebotomus orientalis in the VL focus of Tahtay Adiyabo district, northern Ethiopia. Two separate experiments were conducted testing attraction of P. orientalis to humans, domestic animals, and small wild animals. The host choice of P. orientalis and other sand fly species was assessed using tent traps baited with seven different animals (human, cow, sheep, goat, donkey, dog and chicken) and a blank control. Baited traps were rotated every night in a Latin square design for two consecutive full rounds totaling 16 trap-nights. The second set of experiments tested attraction to small wild animals including; ground squirrel (Xerus rutilus), hare (Lepus sp.), gerbil (Tatera robusta) and spiny mouse (Acomys cahirinus). Animals were caged in standard rodent traps or cylindrical wire-mesh cages. The bait animals were placed in agricultural field and the attracted sand flies were collected using unlit CDC traps for 10 trapping nights. Sand fly specimens collected from each of the experiments were identified to species level and counted. Significant difference (P < 0.05) was observed in the attraction and feeding rate of P. orientalis to different baits. In the first experiment, cow-baited tent traps attracted the highest mean number of P. orientalis (mean = 510 flies). The engorgement rate of P. orientalis on donkey was the highest followed by cow, and much lower on goat, sheep, dog and chicken. In the case of smaller wild animals, more numbers of P. orientalis females were attracted to squirrels followed by hares, gerbils and the spiny rat. However, the engorgement rates for P. orientalis in the smaller animals were very low (1.08%) compared with larger domestic animals (30.53%). The tendency of female P

  5. Geology, geochronology, and paleogeography of the southern Sonoma volcanic field and adjacent areas, northern San Francisco Bay region, California

    USGS Publications Warehouse

    Wagner, David L.; Saucedo, George J.; Clahan, Kevin B.; Fleck, Robert J.; Langenheim, Victoria E.; McLaughlin, Robert J.; Sarna-Wojcicki, Andrei M.; Allen, James R.; Deino, Alan L.

    2011-01-01

    Recent geologic mapping in the northern San Francisco Bay region (California, USA) supported by radiometric dating and tephrochronologic correlations, provides insights into the framework geology, stratigraphy, tectonic evolution, and geologic history of this part of the San Andreas transform plate boundary. There are 25 new and existing radiometric dates that define three temporally distinct volcanic packages along the north margin of San Pablo Bay, i.e., the Burdell Mountain Volcanics (11.1 Ma), the Tolay Volcanics (ca. 10–8 Ma), and the Sonoma Volcanics (ca. 8–2.5 Ma). The Burdell Mountain and the Tolay Volcanics are allochthonous, having been displaced from the Quien Sabe Volcanics and the Berkeley Hills Volcanics, respectively. Two samples from a core of the Tolay Volcanics taken from the Murphy #1 well in the Petaluma oilfield yielded ages of 8.99 ± 0.06 and 9.13 ± 0.06 Ma, demonstrating that volcanic rocks exposed along Tolay Creek near Sears Point previously thought to be a separate unit, the Donnell Ranch volcanics, are part of the Tolay Volcanics. Other new dates reported herein show that volcanic rocks in the Meacham Hill area and extending southwest to the Burdell Mountain fault are also part of the Tolay Volcanics. In the Sonoma volcanic field, strongly bimodal volcanic sequences are intercalated with sediments. In the Mayacmas Mountains a belt of eruptive centers youngs to the north. The youngest of these volcanic centers at Sugarloaf Ridge, which lithologically, chemically, and temporally matches the Napa Valley eruptive center, was apparently displaced 30 km to the northwest by movement along the Carneros and West Napa faults. The older parts of the Sonoma Volcanics have been displaced at least 28 km along the Rodgers Creek fault since ca. 7 Ma. The Petaluma Formation also youngs to the north along the Rodgers Creek–Hayward fault and the Bennett Valley fault. The Petaluma basin formed as part of the Contra Costa basin in the Late Miocene and

  6. Hydrological and erosion processes in terraced agricultural fields: observations from a wet Mediterranean region in northern Portugal

    NASA Astrophysics Data System (ADS)

    Nunes, João Pedro; Bernard-Jannin, Léonard; Rodriguez-Blanco, María Luz; Marisa Santos, Juliana; Oliveira Alves Coelho, Celeste; Keizer, Jan Jacob

    2015-04-01

    Traditional agriculture in the mountainous humid regions of the northwestern Iberian peninsula has relied on terraces for soil retention. In the last decades, a strong afforestation (in many cases with commercial species) has led to the appearance of large forest areas coexisting with traditional agricultural landscapes. Soil erosion research in this region has therefore focused on the impact of forest management practices and associated disturbances such as wildfires. However, there has been little research on the impacts of traditional terracing practices on erosion, and therefore it has been difficult to connect forest research with the wider issue of sediment connectivity in this complex agroforestry landscape. This work tried to address this research gap by monitoring an agricultural terrace in the Caramulo mountains, northern Portugal, during two years. The field site is located in a humid Mediterranean climate region, with c. 1500 mm/y rainfall, overlaying granite bedrock; agricultural practices are a traditional rotation between winter pasture and summer (irrigated) corn cultivation. During this period, the soil properties of the terrace were characterized, and there was a continuous monitoring of rainfall, soil moisture and surface runoff at the outlet, as well as 1 or 2-weekly collections of runoff to measure sediment yield. Occasional measurements of vegetation cover and erosion features (rills) within the plot were also made. Preliminary results indicate that runoff generation occurred mostly due to saturation-excess, possibly linked with the accumulation of groundwater in the lower layers of the soil. After one of the largest events, there was a clear inflow of runoff from outside the terrace, through either the irrigation network linking all terraces or by resurfacing of groundwater. Sediment yield was linked with runoff, but sediment concentration was linked with vegetation cover and was highest during the early stages of pasture growth. However

  7. Comparative evaluation of four registered acaricides for field control of northern fowl mites on caged laying hens.

    PubMed

    Hall, R D; Vandepopuliere, J M; English, L M; Jaynes, W; Lyons, J J; Doisy, K E; Foehse, M C

    1980-11-01

    Carbaryl and tetrachlorvinphos provided longer lasting control of northern fowl mites, Ornithonyssus sylviarum (Canestrini and Fanzago), than did coumaphos or malathion when the materials were applied to caged laying hens as aqueous sprays. The average duration of residual control was ca. 5 weeks for carbaryl, 4.3 weeks for tetrachlorvinphos, 3.5 weeks for coumaphos, and 2 weeks for malathion. No presumptive evidence of northern fowl mite resistance to carbaryl or tetrachlorvinphos was encountered. In contrast, malathion often failed to produce satisfactory control, and difficulty with adequate dispersion of coumaphos wettable powder was noted.

  8. Use of damage surveys and field inventories to evaluate oak and sugar maple health in the northern United States

    Treesearch

    Randall S Morin; Christopher W. Woodall; Jim Steinman; Charles H. Perry

    2009-01-01

    Oak species (Quercus spp.) and sugar maple (Acer saccharum) are substantial components of the forest ecosystems in the 24-state region spanning the northern U.S. During recent decades, both damage surveys and forest inventories have documented declines of sugar maple and oak health. In order to more fully assess the status of oak and sugar maple health, we examined...

  9. Composition and stability of bacterial communities associated with granular activated carbon and anthracite filters in a pilot scale municipal drinking water treatment facility.

    PubMed

    Shirey, T B; Thacker, R W; Olson, J B

    2012-06-01

    Granular activated carbon (GAC) is an alternative filter substrate for municipal water treatment as it provides a high surface area suitable for microbial colonization. The resulting microbial growth promotes biodegradation of organic materials and other contaminants from influent waters. Here, the community structure of the bacteria associated with three GAC and two anthracite filters was examined over 12 months to monitor changes in community composition. Nearly complete 16S rRNA genes were polymerase chain reaction amplified for terminal restriction fragment length polymorphism (T-RFLP) analyses. The identity of commonly occurring peaks was determined through the construction of five representative 16S rRNA clone libraries. Based on sequence analysis, the bacterial communities associated with both anthracite and GAC filters appear to be composed of environmentally derived bacteria, with no known human pathogens. Analysis of similarity tests revealed that significant differences in bacterial community structure occurred over time, with filter substrate playing an important role in determining community composition. GAC filters exhibited the greatest degree of bacterial community variability over the sampling period, while anthracite filters showed a lower degree of variability and less change in community composition. Thus, GAC may be a suitable biologically active filter substrate for the treatment of municipal drinking water.

  10. Removal of oxygen demand and nitrogen using different particle-sizes of anthracite coated with nine kinds of LDHs for wastewater treatment

    NASA Astrophysics Data System (ADS)

    Zhang, Xiangling; Guo, Lu; Wang, Yafen; Ruan, Congying

    2015-10-01

    This paper reports the application of anthracite particles of different sizes and coated with nine kinds of layered double hydroxides (LDHs) varying in MII-MIII cations, as alternative substrates in the simulated vertical-flow constructed wetland columns. Effects of LDHs-coating and particle size of modified anthracites were examined to evaluate their abilities in removing oxygen demand and nitrogen from sewage wastewater. Results showed that LDHs modification effectively enhanced the removal of nitrogen and organics. The removal efficiencies of total nitrogen (TN) , ammonia and chemical oxygen demand (COD) were best improved by 28.5%, 11.9% and 4.1% for the medium particle size (1-3 mm), followed by 9.2%, 5.5% and 13.6% for the large size (3-5 mm), respectively. Only TN removal was improved up to 16.6% for the small particle size (0.5-1 mm). Nitrate tended to accumulate and fluctuate greatly across all the treatments, probably due to the dominancy of aerobic condition in the vertical-flow columns. Overall, MgFe-LDHs was selected as the best-modified coating for anthracite. The results suggested LDHs modification would be one of the promising strategies to provide new-types of highly efficient and lasting wetland substrates.

  11. Removal of oxygen demand and nitrogen using different particle-sizes of anthracite coated with nine kinds of LDHs for wastewater treatment

    PubMed Central

    Zhang, Xiangling; Guo, Lu; Wang, Yafen; Ruan, Congying

    2015-01-01

    This paper reports the application of anthracite particles of different sizes and coated with nine kinds of layered double hydroxides (LDHs) varying in MII–MIII cations, as alternative substrates in the simulated vertical-flow constructed wetland columns. Effects of LDHs-coating and particle size of modified anthracites were examined to evaluate their abilities in removing oxygen demand and nitrogen from sewage wastewater. Results showed that LDHs modification effectively enhanced the removal of nitrogen and organics. The removal efficiencies of total nitrogen (TN) , ammonia and chemical oxygen demand (COD) were best improved by 28.5%, 11.9% and 4.1% for the medium particle size (1–3 mm), followed by 9.2%, 5.5% and 13.6% for the large size (3–5 mm), respectively. Only TN removal was improved up to 16.6% for the small particle size (0.5–1 mm). Nitrate tended to accumulate and fluctuate greatly across all the treatments, probably due to the dominancy of aerobic condition in the vertical-flow columns. Overall, MgFe-LDHs was selected as the best-modified coating for anthracite. The results suggested LDHs modification would be one of the promising strategies to provide new-types of highly efficient and lasting wetland substrates. PMID:26456850

  12. Characteristics of the near-bottom suspended sediment field over the continental shelf off northern California based on optical attenuation measurements during STRESS and SMILE

    USGS Publications Warehouse

    Trowbridge, J.H.; Butman, B.; Limeburner, R.

    1994-01-01

    Time-series measurements of current velocity, optical attenuation and surface wave intensity obtained during the Sediment Transport Events on Shelves and Slopes (STRESS) experiments, combined with shipboard measurements of conductivity, temperature and optical attenuation obtained during the Shelf Mixed Layer Experiment (SMILE), provide a description of the sediment concentration field over the central and outer shelf off northern California. The questions addressed are: (1) existence and characteristics of bottom nepheloid layers and their relationship to bottom mixed layers; (2) characteristics of temporal fluctuations in sediment concentration and their relationship to waves and currents; (3) spatial scales over which suspended sediment concentrations vary horizontally; and (4) vertical distribution of suspended sediment. ?? 1994.

  13. Reliability of biomass burning estimates from savanna fires: Biomass burning in northern Australia during the 1999 Biomass Burning and Lightning Experiment B field campaign

    NASA Astrophysics Data System (ADS)

    Russell-Smith, Jeremy; Edwards, Andrew C.; Cook, Garry D.

    2003-02-01

    This paper estimates the two-daily extent of savanna burning and consumption of fine (grass and litter) fuels from an extensive 230,000 km2 region of northern Australia during August-September 1999 encompassing the Australian continental component of the Biomass Burning and Lightning Experiment B (BIBLE B) campaign [, 2002]. The extent of burning for the study region was derived from fire scar mapping of imagery from the advanced very high resolution radiometer (AVHRR) on board the National Oceanic and Atmospheric Administration (NOAA) satellite. The mapping was calibrated and verified with reference to one Landsat scene and associated aerial transect validation data. Fine fuel loads were estimated using published fuel accumulation relationships for major regional fuel types. It is estimated that more than 43,000 km2 was burnt during the 25 day study period, with about 19 Mt of fine (grass and litter) fuels. This paper examines assumptions and errors associated with these estimates. It is estimated from uncalibrated fire mapping derived from AVHRR imagery that 417,500 km2 of the northern Australian savanna was burnt in 1999, of which 136,405 km2, or 30%, occurred in the Northern Territory study region. Using generalized fuel accumulation equations, such biomass burning consumed an estimated 212.3 Mt of fine fuels, but no data are available for consumption of coarse fuels. This figure exceeds a recent estimate, based on fine fuels only, for the combined Australian savanna and temperate grassland biomass burning over the period 1990-1999 but is lower than past estimates derived from classification approaches. We conclude that (1) fire maps derived from coarse-resolution optical imagery can be applied relatively reliably to estimate the extent of savanna fires, generally with 70-80% confidence using the approach adopted here, over the major burning period in northern Australia and (2) substantial further field assessment and associated modeling of fuel accumulation

  14. Late Holocene lava flow morphotypes of northern Harrat Rahat, Kingdom of Saudi Arabia: Implications for the description of continental lava fields

    NASA Astrophysics Data System (ADS)

    Murcia, H.; Németh, K.; Moufti, M. R.; Lindsay, J. M.; El-Masry, N.; Cronin, S. J.; Qaddah, A.; Smith, I. E. M.

    2014-04-01

    A "lava morphotype" refers to the recognizable and distinctive characteristics of the surface morphology of a lava flow after solidification, used in a similar way to a sedimentary facies. This classification method is explored on an example volcanic field in the Kingdom of Saudi Arabia, where copious lava outpourings may represent an important transition between monogenetic and flood basalt fields. Here, young and well-preserved mafic lava fields display a wide range of surface morphologies. We focussed on four post-4500 yrs. BP lava flow fields in northern Harrat Rahat (<10 Ma) and propose a framework for describing systematic changes in morphotypes down-flow. The morphotypes give insight into intrinsic and extrinsic parameters of emplacement, rheology and dominant flow behavior, as well as the occurrence and character of other lava structures. The Harrat Rahat lava flow fields studied extend up to 23 km from the source, and vary between 1-2 m and 12 m in thickness. Areas of the lava flow fields are between ˜32 and ˜61 km2, with individual flow field volumes estimated between ˜0.085 and ˜0.29 km3. They exhibit Shelly-, Slabby-, and Rubbly-pahoehoe, Platy-, Cauliflower-, and Rubbly-a'a, and Blocky morphotypes. Morphotypes reflect the intrinsic parameters of: composition, temperature, crystallinity and volatile-content/vesicularity; along with external influences, such as: emission mechanism, effusion rate, topography and slope control of flow velocity. One morphotype can transition to another in individual flow-units or lobes and they may dominate zones. Not all morphotypes were found in a single lava flow field. Pahoehoe morphotypes are related to the simple mechanical disaggregation of the crust, whereas a'a morphotypes are related to the transitional emergence and subsequent transitional disappearance of clinker. Blocky morphotypes result from fracturing and auto-brecciation. A'a morphotypes (i.e. platy-, cauliflower-, rubbly-a'a) dominate the lava flow

  15. Analysis of the average poly-cyclic aromatic unit in a meta-anthracite coal using conventional x-ray powder diffraction and intensity separation methods

    SciTech Connect

    Wertz, D.L.; Bissell, M.

    1994-12-31

    X-ray characterizations of coals and coal products have occurred for many years. Hirsch and Cartz measured the diffraction from several coals over the reciprocal space region from s = 0.12 {angstrom}{sup -1} to 7.5 {angstrom}{sup -1} where s = (4{pi}/{lambda}) sin{Theta}. In these studies, a 9 cm powder camera was used to study the high angle region, and a transmission type focusing camera equipped with a LiF monochromator was used for the low angle measurements. They reported that the height of the graphene peak measured for each coal is proportional to the % carbon in the coals. Hirsch also suggested that the ontyberem anthracite has a lamellar diameter of ca. 16 {angstrom} corresponding to an aromatic lamellae of ca. C{sub 87}. For coals with lower carbon content, Hirsch proposed much smaller lamellae; C{sub 19} for a coal with 80% carbon, and C{sub 24} for a coal with 89% carbon. The subject coal for this study is a meta-anthracite which was derived from the Portsmouth, RI mine. The Narragansett Basin contains anthracite and meta-anthracite coals of Pennsylvanian Age. The Basin was a techtonically active non-marine coal-forming basin which has been impacted by several tectonic events. Because of the importance placed by coal scientists no correctly characterizing the nature of the micro-level structural cluster(s) in coals and because of improvements in both x-ray experimentation capabilities and computing power, we have measured the x-ray diffraction and scattering produced from irradiation of this meta-anthracite coal which contains about 94% aromatic carbon. The goal of our study is to determine the intra-planar, and where possible, inter-planar structural details of coals. To accomplish this goal we have utilized the methods normally used for the molecular analysis of non-crystalline condensed phases such as liquids, solutions, and amorphous solids. Reported herein are the results obtained from the high angle x-ray analysis of this coal.

  16. Northern cardiometeopathies.

    PubMed

    Hasnulin, V I; Sevost'yanova, E V; Hasnulina, A V

    2001-04-01

    Our research in high latitudes has allowed the identification of a special class of deadaptive disorders, northern cardiometeopathies, which integrates cardiovascular functional violations connected to biologically significant modifications of meteorological, geomagnetic, electrical, gravitational, rhythmological and other geo-ecological factors of the North. Cardiac and cerebral disorder complexes, and also some psychoemotional modifications manifest cardiometeopathies. Cardiometeopathies can occur with developing of pathology, and in such a case they can be selected in the independent form of deadaptive disease. At the same time, cardiometeopathies in case where cardiovascular pathology already exists could cause complications and become a particular risk factor for the development of injuries and myocardial heart attack. The most important mechanism of cardiometeopathies' formation is the organism's reaction to modifications of the Earth's electromagnetic field, based on internal electromagnetic fields' (first of all pulsing field of heart) dependence on the magnitude and directness of modification of the external electromagnetic fields. The analysis of the high degree of dependence of the blood circulation effiency during geomagnetic perturbations in the North of the modification of electromagnetic heart activity allows us to speak of the discovery of an earlier unknown electromagnetic blood pump.

  17. Long-term active-layer dynamics: results of 22 years of field observations in Northern Hemisphere permafrost regions.

    NASA Astrophysics Data System (ADS)

    Shiklomanov, N. I.; Nelson, F. E.; Streletskiy, D. A.; Klene, A. E.; Biskaborn, B. K.

    2016-12-01

    The uppermost layer of seasonal thawing above permafrost (the active layer) is an important regulator of energy and mass fluxes between the surface and the atmosphere in the polar regions. Active layer monitoring is an important component of efforts to assess the effects of global change in permafrost environments. The Circumpolar Active Layer Monitoring (CALM) program, established in the early 1990s, is designed to observe temporal and spatial variability of the active layer and its response to changes and variations in climatic conditions. The CALM network is an integral part of the Global Terrestrial Network for Permafrost (GTN-P), operating under the auspices of the Global Terrestrial Observing System (GTOS) /Global Climate Observing System (GCOS). Standardized thaw depth observations in the Northern Hemisphere are available for more than 200 GTN-P/CALM sites in the Northern Hemisphere. At each of the sites spatially distributed ALT measurements have been conducted annually by mechanical probing. The locations of sites represent generalized surface and subsurface conditions characteristic of broader regions. The data are assimilated and distributed though the CALM (www.gwu.edu/ calm) and GTN-P (gtnpdatabase.org) online databases. In this presentation we use data from approximately 20 years of continuous observations to examine temporal trends in active-layer thickness for several representative Arctic regions. Results indicate substantial interannual fluctuations in active-layer thickness, primarily in response to variations in air temperature. Decadal trends in ALT vary by region. A progressive increase in ALT has been observed in the Nordic countries, the Russian European North, West Siberia, East Siberia, the Russian Far East, and the Interior of Alaska. North American Arctic sites show no apparent thaw depth trend over 22-years of record. However, combined active layer, ground temperature and heave/subsidence observations conducted in northern Alaska

  18. A Study on Methane and Nitrous Oxide Emissions Characteristics from Anthracite Circulating Fluidized Bed Power Plant in Korea

    PubMed Central

    Lee, Seehyung; Kim, Jinsu; Lee, Jeongwoo; Jeon, Eui-Chan

    2012-01-01

    In order to tackle climate change effectively, the greenhouse gas emissions produced in Korea should be assessed precisely. To do so, the nation needs to accumulate country-specific data reflecting the specific circumstances surrounding Korea's emissions. This paper analyzed element contents of domestic anthracite, calorific value, and concentration of methane (CH4) and nitrous oxide (N2O) in the exhaust gases from circulating fluidized bed plant. The findings showed the concentration of CH4 and N2O in the flue gas to be 1.85 and 3.25 ppm, respectively, and emission factors were 0.486 and 2.198 kg/TJ, respectively. The CH4 emission factor in this paper was 52% lower than default emission factor presented by the IPCC. The N2O emission factor was estimated to be 46% higher than default emission factor presented by the IPCC. This discrepancy can be attributable to the different methods and conditions of combustion because the default emission factors suggested by IPCC take only fuel characteristics into consideration without combustion technologies. Therefore, Korea needs to facilitate research on a legion of fuel and energy consumption facilities to develop country-specific emission factors so that the nation can have a competitive edge in the international climate change convention in the years to come. PMID:22666126

  19. Development of a country-specific CO2 emission factor for domestic anthracite in Korea, 2007-2009.

    PubMed

    Lee, Jeongwoo; Kim, Jinsu; Kim, Seungjin; Im, Gikyo; Lee, Seehyung; Jeon, Eui-Chan

    2011-08-01

    Korea has been making efforts to reduce greenhouse gas (GHG) emissions, including a voluntary commitment to the target of a 30% reduction, based on business-as-usual of the total GHG emission volume, by 2020; 2006 IPCC Guidelines provided default values, applying country-specific emission factors was recommended when estimating national greenhouse gas emissions. This study focused on anthracite produced in Korea in order to provide basic data for developing country-specific emission factor. This study has estimated CO(2) emission factors to use worksheet of which five steps consisted according to the fuel analysis method. As a result, the average of net colorific value for 3 years (2007∼2009) was 4,519 kcal/kg, and the CO(2) emission factor was calculated to be 111,446 kg/TJ, which is about 11.8% lower than the 2006 IPCC guidelines default value, and about 7.9% higher than the US EPA emission factor.

  20. A study on methane and nitrous oxide emissions characteristics from anthracite circulating fluidized bed power plant in Korea.

    PubMed

    Lee, Seehyung; Kim, Jinsu; Lee, Jeongwoo; Jeon, Eui-Chan

    2012-01-01

    In order to tackle climate change effectively, the greenhouse gas emissions produced in Korea should be assessed precisely. To do so, the nation needs to accumulate country-specific data reflecting the specific circumstances surrounding Korea's emissions. This paper analyzed element contents of domestic anthracite, calorific value, and concentration of methane (CH₄) and nitrous oxide (N₂O) in the exhaust gases from circulating fluidized bed plant. The findings showed the concentration of CH₄ and N₂O in the flue gas to be 1.85 and 3.25 ppm, respectively, and emission factors were 0.486 and 2.198 kg/TJ, respectively. The CH₄ emission factor in this paper was 52% lower than default emission factor presented by the IPCC. The N₂O emission factor was estimated to be 46% higher than default emission factor presented by the IPCC. This discrepancy can be attributable to the different methods and conditions of combustion because the default emission factors suggested by IPCC take only fuel characteristics into consideration without combustion technologies. Therefore, Korea needs to facilitate research on a legion of fuel and energy consumption facilities to develop country-specific emission factors so that the nation can have a competitive edge in the international climate change convention in the years to come.

  1. Orgin and significance of geochemical variability among oils and gas-condensates in the Tiger Shoal Field, northern Gulf of Mexico

    SciTech Connect

    Kelley, P.A.; Imbus, S.W.; McKeever, S.R.

    1995-12-31

    Geochemical data placed in geological context is key to understanding the processes controlling the variability of oils and gas-condensates in the Tiger Shoal Field, northern Gulf of Mexico. Thermal maturity at generation and phase partitioning are the principal processes accounting for variability in the bulk and molecular properties of the oils and gas-condensates. Quantification of the extent that these processes altered the oils and gas-condensates between fault blocks and among individual sands permits: (1) documentation of the most effective migration conduits, (2) inference of deeper or shallower pay zones, (3) and assessment of vertical and lateral fluid connectivity. Calibration of bulk to molecular properties will permit rapid assessment of the type and extent of alteration using basic parameters such as API gravity and gas oil ratio (GOR). Upon mass balancing with initial reserves data, a detailed risking scheme for remaining prospects within the field can be formulated.

  2. New Velocity field for Northern Colombia and Western Venezuela and implications for a great earthquake in the Southwest Caribbean

    NASA Astrophysics Data System (ADS)

    Mencin, D.; Mora-Páez, H.; Bilham, R. G.; Mattioli, G. S.; La Femina, P. C.; Audemard, F. A.; Molnar, P. H.; Perez, O. J.

    2016-12-01

    The motion of the Caribbean plate is approximately due east relative to the South American Plate. In NE Venezula, plate motion is largely taken up by pure strike slip motion along the El Pilar fault, but in northern Colombia motion is partitioned between the strike-slip Bocono fault system and normal convergence along the northern coast of Colombia . Recent densification of GPS networks through the NSF funded COLOVEN and COCONet projects, seismic reflection profiles, and revised earthquake locations suggest the existence of incipient oblique subduction zone at 10 mm/yr beneath the coast of NE Colombia. Although there is no history of major subduction zone earthquakes since the arrival of Europeans in the region, and no volcanism indicative of well-established deep subduction, there is evidence for incremental coastal uplift and local subsidence in the past several thousand years, and both local and distant tsunami, which may owe their origin to pre-European arrival events. At Chengue, NE of Santa Marta, a well dated shell and gravel tsunami horizon within a salt marsh sequence, appears to have been emplaced 1200 years ago, and this may correspond to a tsunami deposit of similar age on the southeast Yucatan peninsula, and near Cartagena. The probable rupture area and slip deficit since that time suggests the potential for a great earthquake in the region, with a possible magnitude of 8.0

  3. Evolution of the Latir volcanic field, Northern New Mexico, and its relation to the Rio Grande Rift, as indicated by potassium-argon and fission track dating

    NASA Astrophysics Data System (ADS)

    Lipman, Peter W.; Mehnert, Harald H.; Naeser, Charles W.

    1986-05-01

    Remnants of the Latir volcanic field and cogenetic plutonic rocks are exceptionally exposed along the east margin of the present-day Rio Grande rift by topographic and structural relief in the Sangre de Cristo Mountains of northern New Mexico. Evolution of the magmatic system associated with the Latir field, which culminated in eruption of a regional ash flow sheet (the Amalia Tuff) and collapse of the Questa caldera 26 m.y. ago, has been documented by 74 new potassium-argon (K-Ar) and fission track (F-T) ages. The bulk of the precaldera volcanism, ash flow eruptions and caldera formation, and initial crystallization of the associated shallow granitic batholith took place between 28 and 25 Ma; economically important molybdenum mineralization is related to smaller granitic intrusions along the south margin of the Questa caldera at about 23 Ma. Interpretation of the radiogenic ages within this relatively restricted time span is complicated by widespread thermal resetting of earlier parts of the igneous sequence by later intrusions. Many samples yielded discordant ages for different mineral phases. Thermal blocking temperatures decrease in the order: K-Ar sanidine > K-Ar biotite > F-T zircon ≫ F-T apatite. The F-T results are especially useful indicators of cooling and uplift rates. Upper portions of the subvolcanic batholith, that underlay the Questa caldera, cooled to about 100°C within about a million years of emplacement; uplift of the batholith increases to the south along this segment of the Sangre de Cristo Mountains. Activity in the Latir volcanic field was concurrent with southwest directed extension along the early Rio Grande rift zone in northern New Mexico and southern Colorado. The geometry of this early rifting is compatible with interpretation as back arc extension related to a subduction system dipping gently beneath the cordilleran region of the American plate. The Latir field lies at the southern end of a southward migrating Tertiary magmatic

  4. Evaluation of the field dissipation of fungicides and insecticides used on fruit bearing trees in northern Italy.

    PubMed

    Passarella, Iride; Elia, Irene; Guarino, Barbara; Bourlot, Giancarlo; Nègre, Michèle

    2009-02-01

    The dissipation of the fungicides captan, cyprodinil, fludioxonil, dithianon, and tebuconazole and of the insecticides chlorpyrifos, fenitrothion, and malathion was studied, following a single treatment of different cultivars of pears, apples, and peaches. The study was conducted in northern Italy, over two successive growing seasons (2004 and 2005). The treatments were performed by the farmers involved, in line with their usual practice. At various time intervals from treatment to harvest, representative samples of fruit were collected and analyzed for pesticide residues. In some cases, concentrations lower than the maximum residue levels (MRLs) were found immediately after treatment. In all trials a rapid decline in pesticide concentrations was observed leading to residues at harvest greatly below the MRLs.

  5. Distribution and characteristic of nitrite-dependent anaerobic methane oxidation bacteria by comparative analysis of wastewater treatment plants and agriculture fields in northern China

    PubMed Central

    Ma, Ru

    2016-01-01

    Nitrite-dependent anaerobic methane oxidation (n-damo) is a recently discovered biological process which has been arousing global attention because of its potential in minimizing greenhouse gases emissions. In this study, molecular biological techniques and potential n-damo activity batch experiments were conducted to investigate the presence and diversity of M. oxyfera bacteria in paddy field, corn field, and wastewater treatment plant (WWTP) sites in northern China, as well as lab-scale n-damo enrichment culture. N-damo enrichment culture showed the highest abundance of M. oxyfera bacteria, and positive correlation was observed between potential n-damo rate and abundance of M. oxyfera bacteria. Both paddy field and corn field sites were believed to be better inoculum than WWTP for the enrichment of M. oxyfera bacteria due to their higher abundance and the diversity of M. oxyfera bacteria. Comparative analysis revealed that long biomass retention time, low NH\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}${}_{4}^{+}$\\end{document}4+ and high NO\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}${}_{2}^{-}$\\end{document}2− content were suitable for the growth of M. oxyfera bacteria. PMID:27994974

  6. Distribution and characteristic of nitrite-dependent anaerobic methane oxidation bacteria by comparative analysis of wastewater treatment plants and agriculture fields in northern China.

    PubMed

    Hu, Zhen; Ma, Ru

    2016-01-01

    Nitrite-dependent anaerobic methane oxidation (n-damo) is a recently discovered biological process which has been arousing global attention because of its potential in minimizing greenhouse gases emissions. In this study, molecular biological techniques and potential n-damo activity batch experiments were conducted to investigate the presence and diversity of M. oxyfera bacteria in paddy field, corn field, and wastewater treatment plant (WWTP) sites in northern China, as well as lab-scale n-damo enrichment culture. N-damo enrichment culture showed the highest abundance of M. oxyfera bacteria, and positive correlation was observed between potential n-damo rate and abundance of M. oxyfera bacteria. Both paddy field and corn field sites were believed to be better inoculum than WWTP for the enrichment of M. oxyfera bacteria due to their higher abundance and the diversity of M. oxyfera bacteria. Comparative analysis revealed that long biomass retention time, low NH[Formula: see text] and high NO[Formula: see text] content were suitable for the growth of M. oxyfera bacteria.

  7. Abandoned mine drainage in the Swatara Creek Basin, southern anthracite coalfield, Pennsylvania, USA: 2. performance of treatment systems

    USGS Publications Warehouse

    Cravotta, Charles A.

    2010-01-01

    A variety of passive and semi-passive treatment systems were constructed by state and local agencies to neutralize acidic mine drainage (AMD) and reduce the transport of dissolved metals in the upper Swatara Creek Basin in the Southern Anthracite Coalfield in eastern Pennsylvania. To evaluate the effectiveness of selected treatment systems installed during 1995–2001, the US Geological Survey collected water-quality data at upstream and downstream locations relative to each system eight or more times annually for a minimum of 3 years at each site during 1996–2007. Performance was normalized among treatment types by dividing the acid load removed by the size of the treatment system. For the limestone sand, open limestone channel, oxic limestone drain, anoxic limestone drain (ALD), and limestone diversion well treatment systems, the size was indicated by the total mass of limestone; for the aerobic wetland systems, the size was indicated by the total surface area of ponds and wetlands. Additionally, the approximate cost per tonne of acid treated over an assumed service life of 20 years was computed. On the basis of these performance metrics, the limestone sand, ALD, oxic limestone drain, and limestone diversion wells had similar ranges of acid-removal efficiency and cost efficiency. However, the open limestone channel had lower removal efficiency and higher cost per ton of acid treated. The wetlands effectively attenuated metals transport but were relatively expensive considering metrics that evaluated acid removal and cost efficiency. Although the water-quality data indicated that all treatments reduced the acidity load from AMD, the ALD was most effective at producing near-neutral pH and attenuating acidity and dissolved metals. The diversion wells were effective at removing acidity and increasing pH of downstream water and exhibited unique potential to treat moderate to high flows associated with storm flow conditions.

  8. Essential oils as potential adulticides against two populations of Aedes aegypti, the laboratory and natural field strains, in Chiang Mai province, northern Thailand.

    PubMed

    Chaiyasit, Dana; Choochote, Wej; Rattanachanpichai, Eumporn; Chaithong, Udom; Chaiwong, Prasong; Jitpakdi, Atchariya; Tippawangkosol, Pongsri; Riyong, Doungrat; Pitasawat, Benjawan

    2006-11-01

    Essential oils derived from five plant species, celery (Apium graveolens), caraway (Carum carvi), zedoary (Curcuma zedoaria), long pepper (Piper longum), and Chinese star anise (Illicium verum), were subjected to investigation of adulticidal activity against mosquito vectors. Two populations of Aedes aegypti, the laboratory and natural field strains, collected in Chiang Mai province, northern Thailand were tested in pyrethroid-susceptibility bioassays. The results revealed that the natural field strain of A. aegypti was resistant to permethrin, with mortality rates ranging from 51 to 66%. A mild susceptibility, with mortality rates ranging from 82 to 88%, was observed in the natural field strain of A. aegypti exposed to lambdacyhalothrin, which suggested that this strain was tolerant and might be resistant to this insecticide. However, laboratory-reared A. aegypti exposed to discriminating dosages of permethrin and lambdacyhalothrin induced 100% mortality in all cases, thus indicating complete susceptibility of this strain to these insecticides. The adulticidal activity determined by topical application revealed that all five essential oils exerted a promising adulticidal efficacy against both laboratory and natural field strains of A. aegypti. Although the laboratory strain was slightly more susceptible to these essential oils than the natural field strain, no statistically significant difference was observed. Moreover, comparison of the adulticidal activity indicated that the performance of these essential oils against the two strains of A. aegypti was similar. The highest potential was established from caraway, followed by zedoary, celery, long pepper, and Chinese star anise, with an LC(50) in the laboratory strain of 5.44, 5.94, 5.96, 6.21, and 8.52 microg/mg female, respectively, and 5.54, 6.02, 6.14, 6.35, and 8.83 microg/mg female, respectively, in the field strain. These promising essential oils are, therefore, an alternative in developing and producing

  9. Late Holocene lava flow morphotypes of the northern Harrat Rahat, Kingdom of Saudi Arabia: implications for the description of continental lava fields

    NASA Astrophysics Data System (ADS)

    Murcia, H. F.; Nemeth, K.; Moufti, R.; Lindsay, J. M.; El-Masry, N.; Cronin, S. J.; Qaddah, A.; Smith, I. E.

    2013-12-01

    Lava morphotype refers to the surface morphology of a lava flow after solidification. In Saudi Arabia, young and well-preserved mafic lava fields (Harrats) display a wide range of these morphotypes. This study examines those exhibited by four of the post-4500 yrs. BP lava fields in the northern Harrat Rahat (<10 Ma) and describes these lava fields from general characteristics to detailed lava structures. This study also discusses the relationship between rheology and morphotypes, and proposes a preliminary correlation with whole-rock chemical composition. The Harrat Rahat lava fields include one or more lobes that may extend over 20 km from the source, with thicknesses varying between 1-2 m up to 12 m. Each lava flow episode covered areas between ~32 and ~61 km2, with individual volumes estimated between ~0.085 and ~0.29 km3. The whole-rock chemical compositions of these lavas lie between 44.3 to 48.4% SiO2, 9.01-4.28% MgO and 3.13-6.19% NaO+K2O. Seven different morphotypes with several lava structures are documented: Shelly, Slabby, Rubbly-pahoehoe, Platy, Cauliflower, Rubbly-a'a, and Blocky. These may be related to the shear strain and/or apparent viscosity of the lava flows formed from typical pahoehoe (pure or Hawaiian-pahoehoe, or sheet-pahoehoe). The well-preserved lava fields in Harrat Rahat allow the development of a more expanded classification scheme than has been traditionally applied. In addition to the whole-rock composition, these morphotypes may be indicators of other properties such as vesicularity, crystallization, effusion mechanism, as well as significant along-flow variations in topography and lava thickness and temperature that modify the rheology. The linearity of transitions between morphotypes observed in the lava fields suggest that real time forecasting of the evolution of lava flows might be possible.

  10. Preparing the Field for Feasibility Testing of a Parenting Intervention for War-Affected Mothers in Northern Uganda.

    PubMed

    Wieling, Elizabeth; Mehus, Christopher; Yumbul, Cigdem; Möllerherm, Julia; Ertl, Verena; Laura, Achan; Forgatch, Marion; Neuner, Frank; Catani, Claudia

    2015-10-26

    In this article, we discuss the successful implementation of an adapted evidence-based parenting intervention for families affected by two decades of war in Northern Uganda. The adaptation and adoption of such interventions to support mental health and family functioning is widely endorsed by prevention scientists and considered a priority in global mental health. The preparation and early adoption phases of engaging with a highly vulnerable community affected by war trauma are documented in this paper along with a discussion of the steps taken to adapt a parenting intervention for cultural and contextual fit. This study is a component of an overall program of research aimed at reducing the long-term negative effects of war on parenting practices and childhood outcomes, which have considerable implications for preventing mental, neurological, and substance-use disorders. The processes described here cover a 4-year period culminating in the implementation of the nine-session Enhancing Family Connection intervention piloted with a group of 14 mothers. The lessons in cultural adaptation have been valuable and the feasibility results promising for further testing the intervention.

  11. Seasonal thermal fronts on the northern South China Sea shelf: Satellite measurements and three repeated field surveys

    NASA Astrophysics Data System (ADS)

    Jing, Zhiyou; Qi, Yiquan; Fox-Kemper, Baylor; Du, Yan; Lian, Shumin

    2016-03-01

    Seasonal thermal fronts associated with wind-driven coastal downwelling/upwelling in the northern South China Sea are investigated using satellite measurements and three repeated fine-resolution mapping surveys in winter, spring, and summer. The results show that vigorous thermal fronts develop over the broad shelf with variable widths and intensities in different seasons, which tend to be approximately aligned with the 20-100 m isobaths. Driven by the prevailing winter/summer monsoon, the band-shaped fronts were observed with a magnitude exceeding 0.1°C/km in the subsurface, and accompanied by energetic coastal downwelling/upwelling due to shoreward/offshore Ekman transport. The downward/upward tilting of seasonal thermoclines across the shelf exceeds 20 m, significantly contributing to the development of thermal fronts over the shelf. In addition, the diagnostic analysis of Potential Vorticity (PV) suggests that the summer frontal activities induced by the coastal upwelling are more stable to convection and symmetric instabilities in comparison to the winter fronts associated with downwelling-favorable monsoon forcing. This is primarily due to their essential differences in the upper ocean stratification and horizontal buoyancy gradients arising from wind forcing. At the same time, the coastal currents are substantially regulated by the seasonal winds. An expected lag correlation between the velocity from mooring measurements and alongshore wind stress is detected near the frontal region. These results indicate that seasonal wind forcing plays an important role in the frontal activities and coastal water transport over the shelf.

  12. Inter-Group Conflict and Cooperation: Field Experiments Before, During and After Sectarian Riots in Northern Ireland.

    PubMed

    Silva, Antonio S; Mace, Ruth

    2015-01-01

    The idea that cooperative groups out-compete less cooperative groups has been proposed as a theoretical possibility for the evolution of cooperation through cultural group selection. Previous studies have found an association between increased cooperation and exposure to inter-group violence, but most have not been able to identify the specific target of cooperation and are based on correlational data making it difficult to establish causality. In this study we test the hypothesis that inter-group conflict promotes parochial altruism (i.e., in-group altruism and out-group hostility) by using longitudinal data of a real-world measure of cooperation-charity and school donations-sampled before, during and after violent sectarian riots between Catholics and Protestants in Belfast, Northern Ireland. We find that conflict is associated with reductions in all types of cooperation, with reduced donations to a neutral charity, and both in-group and out-group primary schools. After the conflict, both in-group and out-group donations increased again. In this context we find no evidence that inter-group conflict promotes parochial altruism.

  13. Inter-Group Conflict and Cooperation: Field Experiments Before, During and After Sectarian Riots in Northern Ireland

    PubMed Central

    Silva, Antonio S.; Mace, Ruth

    2015-01-01

    The idea that cooperative groups out-compete less cooperative groups has been proposed as a theoretical possibility for the evolution of cooperation through cultural group selection. Previous studies have found an association between increased cooperation and exposure to inter-group violence, but most have not been able to identify the specific target of cooperation and are based on correlational data making it difficult to establish causality. In this study we test the hypothesis that inter-group conflict promotes parochial altruism (i.e., in-group altruism and out-group hostility) by using longitudinal data of a real-world measure of cooperation—charity and school donations—sampled before, during and after violent sectarian riots between Catholics and Protestants in Belfast, Northern Ireland. We find that conflict is associated with reductions in all types of cooperation, with reduced donations to a neutral charity, and both in-group and out-group primary schools. After the conflict, both in-group and out-group donations increased again. In this context we find no evidence that inter-group conflict promotes parochial altruism. PMID:26640449

  14. A field test of temperature effects on ecophysiological responses of copepodid Calanus chilensis during coastal upwelling in northern Chile

    NASA Astrophysics Data System (ADS)

    Giraldo, Alan; Escribano, Ruben; Marín, Victor

    2006-08-01

    We assessed responses of late copepodid stages of Calanus chilensis, as subject to spatial heterogeneity in oceanographic conditions, during coastal upwelling off Mejillones Peninsula, northern Chile. An oceanographic survey conducted during 26 h prior to zooplankton sampling mapped upwelling conditions. Over the next 2 d, four zooplankton stations, two inside and two outside the cold upwelling plume, were sampled twice in the day and twice at night. We then tested the effects of upwelling/non-upwelling habitat (i.e. inside/outside the upwelling plume) on body length, body weight, oil-sac volume (OSV) and a condition index (CI) of stages copepodid C5 and adult female. We also compared ovary development of females and stage distribution from both habitats. C5 and females from inside the upwelling plume were heavier, larger, had a greater CI, and females had more developed ovaries, than those located outside the plume, although there were no significant differences in the OSV. Differences in stage distribution suggested that individuals outside the plume had developed faster under a higher temperature ( 17C) than those inside the cold ( 14C) plume. Chlorophyll- a concentration was uniformly high ( >4mgm-3), both outside and inside the plume. We concluded that distinct temperature regimes, persisting longer than 1 week, had caused different sized copepodids. We thus suggest that temperature alone may substantially explain variances in growth and development rates of Calanus in highly productive upwelling systems, with no need to invoke food and body size effects.

  15. Free-swimming northern elephant seals have low field metabolic rates that are sensitive to an increased cost of transport.

    PubMed

    Maresh, Jennifer L; Simmons, Samantha E; Crocker, Daniel E; McDonald, Birgitte I; Williams, Terrie M; Costa, Daniel P

    2014-05-01

    Widely ranging marine predators often adopt stereotyped, energy-saving behaviours to minimize the energetic cost of transport while maximizing energy gain. Environmental and anthropogenic disturbances can disrupt energy balance by prompting avoidance behaviours that increase transport costs, thereby decreasing foraging efficiency. We examined the ability of 12 free-ranging, juvenile northern elephant seals (Mirounga angustirostris) to mitigate the effects of experimentally increased transport costs by modifying their behaviour and/or energy use in a compensatory manner. Under normal locomotion, elephant seals had low energy requirements (106.5±28.2 kJ kg(-1) day(-1)), approaching or even falling below predictions of basal requirements. Seals responded to a small increase in locomotion costs by spending more time resting between dives (149±44 s) compared with matched control treatments (102±11 s; P<0.01). Despite incurred costs, most other dive and transit behaviours were conserved across treatments, including fixed, rhythmic swimming gaits. Because of this, and because each flipper stroke had a predictable effect on total costs (P<0.001), total energy expenditure was strongly correlated with time spent at sea under both treatments (P<0.0001). These results suggest that transiting elephant seals have a limited capacity to modify their locomotory behaviour without increasing their transport costs. Based on this, we conclude that elephant seals and other ocean predators occupying similar niches may be particularly sensitive to increased transport costs incurred when avoiding unanticipated disturbances.

  16. Sequence stratigraphic setting of turbidite-related petroleum fields, Green Canyon and Ewing Bank lease areas, northern Gulf of Mexico

    SciTech Connect

    Weimer, P.; Pulham, A.J.

    1996-08-01

    The Green Canyon (GC) and Ewing Bank (EW) OCS lease areas have 17 discoveries/fields, primarily from bathyal turbidite systems. Salt has played a significant role in the formation of the intraslope basins that the turbidite systems were deposited in, by influencing the flows of turbidities throughout the basin, in the subsequent trap formation, and, in some cases, as a seal. Nearly every field/discovery is associated with a seismic amplitude anomaly. Fields generally have multiple pay zones, with up to 22 in GC 184 (Jolliet). To date, eight of the fields are producing: EB 826, EB 873 (Lobster), GC 6 (Kodiak), GC 18, GC 53/54 (Marquette), GC 65/110 (Bullwinkle), GC 184 (Jolliet), and GC 205 (Vancouver). Other fields expected to be developed are GC 72/116 (Popeye), GC 254 (Allegheny), GC 200/244 (Olivella), GC and GC 166 (Bison). Other discoveries that were produced and then abandoned include GC 19, and GC29. Producing reservoir facies are highly variable across the area. Turbidite reservoir geometries in Pliocene sands (>1.6 Ma) consist of sheets and amalgamated sheet sands. Pleistocene sands are characterized primarily from channel-levee systems and related deposits. These sands tend to more compartmentalized with separate oil/water or gas/water contacts. Most reservoir sands occur within 100 ft overlying a sequence boundary, indicating the eustatic control on the timing of reservoir sand deposition.

  17. Detection of hydrocarbon microseepage in a rain forest environment (Jurua Gas field, northern Brazil) using Landsat MSS data

    SciTech Connect

    Miranda, F.P.; Cunha, F.M.B. )

    1990-05-01

    The Jurua gas field is the first important hydrocarbon accumulation found in the jungle-covered Solimoes basin. The tectonic framework in this area is characterized by a right-lateral transpressional zone (Jurua structural trend). Hydrocarbon traps are anticlines developed along the upthrown block of a reverse fault. The prospective 2,200-m-thick Paleozoic section is unconformably covered by a 2,800-m-thick pile of Mesozoic and Cenozoic continental sediments. Anomalous concentrations of hydrocarbons (C{sub 2}-C{sub 4}) in soil samples are concordantly aligned with the trace of the reverse fault crossing the gas field, indicating that this feature acted as a conduit for hydrocarbon microseepage. Gas-producing wells are located over a tabular watershed which coincides with the northeast-southwest Jurua structural trend. An unsupervised classification of Landsat MSS data over the gas field area reveals that one spectral class of vegetation is aligned with the Jurua structural trend. Field checking shows that the vegetation near the gas-producing well 1-JR-1-AM is not as dense as the forest outside the limits of the Jurua gas field. Two geologic factors may account for the vegetation anomaly over the gas field. (1) The northeast-southwest tabular watershed corresponds to a Pleistocene erosional surface associated with weathering products such as bauxite and laterite. The resulting soil is impermeable and low in nutrients. (2) The spectral behavior of vegetation may represent the response of plants to long-term anaerobic soil conditions brought about by gas leakage from the Paleozoic reservoir.

  18. Ground Penetrating Radar Field Studies of Lunar-Analog Geologic Settings and Processes: Barringer Meteor Crater and Northern Arizona Volcanics

    NASA Astrophysics Data System (ADS)

    Russell, P. S.; Grant, J. A.; Williams, K. K.; Bussey, B.

    2010-12-01

    Ground-Penetrating Radar (GPR) data from terrestrial analog environments can help constrain models for evolution of the lunar surface, aid in interpretation of orbital SAR data, and help predict what might be encountered in the subsurface during future, landed, scientific or engineering operations on the Moon. GPR can yield insight into the physical properties, clast-size distribution, and layering of the subsurface, granting a unique view of the processes affecting an area over geologic time. The purpose of our work is to demonstrate these capabilities at sites at which geologic processes, settings, and/or materials are similar to those that may be encountered on the moon, especially lava flows, impact-crater ejecta, and layered materials with varying properties. We present results from transects obtained at Barringer Meteor Crater, SP Volcano cinder cone, and Sunset Crater Volcano National Monument, all in northern Arizona. Transects were taken at several sites on the ejecta of Meteor Crater, all within a crater radius (~400 m) of the crater rim. Those taken across ejecta lobes or mounds reveal the subsurface contact of the ejecta upper surface and overlying, embaying sediments deposited by later alluvial, colluvial, and/or aeolian processes. Existing mine shafts and pits on the south side of the crater provide cross sections of the subsurface against which we compare adjacent GPR transects. The ‘actual’ number, size, and depth of clasts in the top 1-2 m of the subsurface are estimated from photos of the exposed cross sections. In GPR radargrams, reflections attributed to blocks in the top 2-5 m of the subsurface are counted, and their depth distribution noted. Taking GPR measurements along a transect at two frequencies (200 and 400 MHz) and to various depths, we obtain the ratio of the actual number of blocks in the subsurface to the number detectable with GPR, as well as an assessment of how GPR detections in ejecta decline with depth and depend on antenna

  19. Dissolved organic carbon in peat porewater increases with warming: a field manipulation experiment in a northern temperate bog

    NASA Astrophysics Data System (ADS)

    Kane, E. S.; Mazzoleni, L. R.; Kratz, C. J.; Hribljan, J. A.; Johnson, C. P.; Pypker, T. G.; Chimner, R. A.

    2010-12-01

    Studies conducted across northern Europe and North America have shown increases in dissolved organic carbon (DOC) in lake and stream water in recent decades. While there is little consensus as to the exact mechanisms for the increases in DOC, hypotheses converge on such climate change factors as warming, increased precipitation variability, and changes in atmospheric deposition, and their effects on catchment processes. In this study, we tested the effects of warming on peat porewater composition by actively warming a peatland with infrared lamps mounted 1.24 m above the peat surface for two years. Mean growing season peat temperatures in the warmed plots (n=5) were 1.9 ± 0.4 °C warmer than the control plots at 5 cm depth (t statistic = 5.03, p = 0.007). Mean porewater DOC concentrations measured throughout the growing season were 15% higher in the warmed plots (73.9 ± 3.6 mg L-1) than in the control plots (64.1 ± 2.9 mg L-1) at 25 cm (t statistic = 3.50, p = 0.01). While total dissolved nitrogen (TDN) concentrations were not affected by the warming, changes in dissolved organic N followed the trends in DOC. DOC from the warmed plots decayed nearly twice as fast as control plot DOC in 2 month laboratory incubations, and had a higher relative abundance of low molecular weight organic matter associated with cellulose and aminosugars (as determined by ultra high resolution electrospray ionization mass spectrometry). Complementary research of ecosystem C cycling at the site also showed warming increased net primary production, and together with preliminary analysis of changes in extracellular enzymes suggest that at least part of the increased DOC concentrations observed with warming was derived from microbial/plant interactions in the rhizosphere.

  20. Spatial and temporal variation of bulk snow properties in northern boreal and tundra environments based on extensive field measurements

    NASA Astrophysics Data System (ADS)

    Hannula, Henna-Reetta; Lemmetyinen, Juha; Kontu, Anna; Derksen, Chris; Pulliainen, Jouni

    2016-08-01

    An extensive in situ data set of snow depth, snow water equivalent (SWE), and snow density collected in support of the European Space Agency (ESA) SnowSAR-2 airborne campaigns in northern Finland during the winter of 2011-2012 is presented (ESA Earth Observation Campaigns data 2000-2016). The suitability of the in situ measurement protocol to provide an accurate reference for the simultaneous airborne SAR (synthetic aperture radar) data products over different land cover types was analysed in the context of spatial scale, sample spacing, and uncertainty. The analysis was executed by applying autocorrelation analysis and root mean square difference (RMSD) error estimations. The results showed overall higher variability for all the three bulk snow parameters over tundra, open bogs and lakes (due to wind processes); however, snow depth tended to vary over shorter distances in forests (due to snow-vegetation interactions). Sample spacing/sample size had a statistically significant effect on the mean snow depth over all land cover types. Analysis executed for 50, 100, and 200 m transects revealed that in most cases less than five samples were adequate to describe the snow depth mean with RMSD < 5 %, but for land cover with high overall variability an indication of increased sample size of 1.5-3 times larger was gained depending on the scale and the desired maximum RMSD. Errors for most of the land cover types reached ˜ 10 % if only three measurements were considered. The collected measurements, which are available via the ESA website upon registration, compose an exceptionally large manually collected snow data set in Scandinavian taiga and tundra environments. This information represents a valuable contribution to the snow research community and can be applied to various snow studies.

  1. Seismicity in the vicinity of the natural gas fields of Völkersen und Söhlingen (Northern Germany) - looking for imperceptible seismic events

    NASA Astrophysics Data System (ADS)

    Plenefisch, Thomas; Gestermann, Nicolai; Ceranna, Lars; Wegler, Ulrich; Vasterling, Margarete; Bischoff, Monika

    2014-05-01

    Northern Germany is a region of relatively low seismic activity with only some rare and singular tectonic events. However, during the last decades seismic events consistently occurred in the vicinity of the natural gas fields in Northern Germany. Due to their spatial vicinity and their temporal appearance just starting after the beginning of extraction they are ranked as induced events. Altogether, 35 events in the magnitude range 1.9 to 4.5 could have been detected in the time span between 1976 and 2013. Most of them were felt by parts of the inhabitants whereas the strongest one, the magnitude 4.5 event close to the village of Rotenburg on 20th October 2004, has even been felt in Hamburg 65 km away from the epicenter near Rotenburg. During the last years the majority of events took place in the vicinity of the two natural gas fields Völkersen and Söhlingen. Several new installed surface and borehole stations have recently improved the monitoring capabilities in the region. However, it is still difficult to detect and analyze events with magnitude below 2 due to bad noise-conditions invoked by the thick sediments as well as to the relatively large area to be covered. Up to now, it is not clear whether the small number of fore- and aftershocks is an inherent characteristic of the induced events and thereby different from tectonic earthquake sequences or only the effect of the non appropriate seismic surveillance during the last decades. Here, we present several approaches to retrieve weak events for the region of the Völkersen natural gas field and discuss their implications. Thereto, detection algorithms are applied on the basis of cross-correlation techniques and similarities of already recorded and identified waveforms of stronger events. Moreover array techniques are applied to the recordings of a small cluster of temporary stations that are installed in the middle of 2012 to improve the signal-to-noise ratio. In the same way the Gorleben seismic network

  2. Evaluation of two commercial field test kits used for screening of groundwater for arsenic in Northern India.

    PubMed

    Sankararamakrishnan, Nalini; Chauhan, Divya; Nickson, R T; Tripathi, R M; Iyengar, L

    2008-08-15

    In this study two relatively new arsenic field kits, namely Wagtech Digital Arsenator (WFTK) and Chem-In Corp field test kit (CFTK) for arsenic were evaluated. The response of the two field test kits to known standards (Both As(III) and As(V)) is detailed. In addition around 157 arsenic-contaminated field samples obtained from various locations of Ballia and Kanpur districts, U.P., India were tested using the two kits and the results were compared with the laboratory-based colorimetric method (silver diethyldithiocarbamate method, SDDC). The concentration of arsenic in the 157 samples ranged from 0 to 468 microg l(-1). WFTK is seen to be suitable for measuring arsenic concentration <5-100 microg l(-1) using the digital meter. CFTK was not able to detect As(V) and its usage is cautioned in Uttar Pradesh where As(V) is seen to occur in appreciable concentrations. The Pearson's correlation between the silver diethyldithiocarbamate method and WFTK was found to be 0.87 and for the corresponding correlation with CFTK was 0.41 in the concentration range used in this study. Spearman's rank correlation coefficients comparing the WFTK and CFTK to laboratory measurements in the concentration range of 0-100 microg l(-1) were 0.95 (p<0.001) and 0.64 (p<0.001) respectively.

  3. Old problems on a new playing field: Helminth zoonoses transmitted among dogs, wildlife, and people in a changing northern climate.

    PubMed

    Jenkins, Emily J; Schurer, Janna M; Gesy, Karen M

    2011-11-24

    Although surveillance is limited, indigenous residents at latitudes ranging from 53 to 73°N in Canada appear to have a higher occurrence of infection with some zoonotic parasites than the general population. Conversely, they are relatively naïve to other zoonotic parasites that have previously been unable to establish at northern latitudes. For those parasites that circulate among dogs, wildlife, and people, potential risk factors in the North include limited availability of veterinary services, presence of free-roaming dog populations, and consumption of locally harvested fish and wildlife. These regions are also experiencing some of the greatest impacts of climate change in North America, including increased temperature, precipitation, and frequency and severity of extreme weather. We review the current taxonomy, genetic diversity, host and geographic distributions, epidemiology and risk factors for 3 genera of helminths (Diphyllobothrium spp., Echinococcus spp., and Toxocara sp.) in Canada's North in order to identify climate-sensitive aspects of their ecology. Free-living stages of parasitic zoonoses endemic in the Arctic (such as Diphyllobothrium dendriticum, the cervid strain of Echinococcus granulosus, and Arctic strains of Echinococcus multilocularis) will experience trade-offs between enhanced survival under wetter conditions and increased mortality under warmer conditions. Climate change might also lead to the introduction and establishment in the Arctic of parasitic zoonoses previously restricted to the sub-Arctic, such as Diphyllobothrium latum, Toxocara canis, and the prairie strain of E. multilocularis. Molecular techniques applied in broad geographic surveys are needed to address critical knowledge gaps in the geographic distribution, genetic diversity, and public health significance of zoonotic helminths already in the circumpolar North, and to determine the current barriers to range expansion of temperate-adapted parasites into the North. Dogs

  4. Characteristics of carbonaceous aerosols in Emilia-Romagna (Northern Italy) based on two fall/winter field campaigns

    NASA Astrophysics Data System (ADS)

    Costa, V.; Bacco, D.; Castellazzi, S.; Ricciardelli, I.; Vecchietti, R.; Zigola, C.; Pietrogrande, M. C.

    2016-01-01

    The carbonaceous aerosol in Emilia-Romagna region (Northern Italy) was characterized in two fall/winter monitoring campaigns conducted through the years 2011-2012 and 2012-2013. Nearly 650 PM2.5 samples were collected at three monitoring stations describing urban background (main city Bologna, MS, Parma and Rimini) and one rural background site (San Pietro, SP). OC and EC values were measured by the thermal-optical transmittance method (TOT). Low flow-rate sampling strategy (24 m3 air volume per day) was used to reduce loading of light absorbing material on the filter surface in order to ensure the correct OC/EC discrimination. The TC values measured in winter 2011-2012 ranged from 9.8 μgC m- 3 at San Pietro to 12.0 μgC m- 3 at Parma, consisting of OC from 8.6 μgC m- 3 at SP to 9.9 μgC m- 3 at MS and EC from 1.3 μgC m- 3 at SP to 2.5 μgC m- 3 at Rimini. In winter 2012-2013, lower values were in general found with TC values ranging from 7.8 to 9.1 μgC m- 3 consisting of OC from 5.1 to 7.0 μgC m- 3 and EC from 1.5 to 2.2 μgC m- 3. Such differences can be likely explained by higher pollutant emissions related to domestic heating in colder fall/winter 2011/2012 (mean temperature ≈ 2 °C in comparison with ≈ 7 °C in winter 2012/2013). This hypothesis is supported by high levels of levoglucosan, as unambiguous tracer for biomass burning emission, and of polycyclic aromatic hydrocarbons related to combustion (levoglucosan ≃ 1000 ng m- 3 and burning PAHs ≃ 4 ng m- 3 at MS and SP sites).

  5. Evolution of silicic magma in the upper crust: the mid-Tertiary Latir volcanic field and its cogenetic granitic batholith, northern New Mexico, USA

    USGS Publications Warehouse

    Lipman, P.W.

    1988-01-01

    Structural and topographic relief along the eastern margin of the Rio Grande rift, northern New Mexico, provides a remarkable cross-section through the 26-Ma Questa caldera and cogenetic volcanic and plutonic rocks of the Latir field. Exposed levels increase in depth from mid-Tertiary depositional surfaces in northern parts of the igneous complex to plutonic rocks originally at 3-5 km depths in the S. Erosional remnants of an ash-flow sheet of weakly peralkaline rhyolite (Amalia Tuff) and andesitic to dactitic precursor lavas, disrupted by rift-related faults, are preserved as far as 45 km beyond their sources at the Questa caldera. Broadly comagmatic 26 Ma batholithic granitic rocks, exposed over an area of 20 by 35 km, range from mesozonal granodiorite to epizonal porphyritic granite and aplite; shallower and more silicic phases are mostly within the caldera. Compositionally and texturally distinct granites defined resurgent intrusions within the caldera and discontinuous ring dikes along its margins: a batholithic mass of granodiorite extends 20 km S of the caldera and locally grades vertically to granite below its flat-lying roof. A negative Bouguer gravity anomaly (15-20 mgal), which encloses exposed granitic rocks and coincides with boundaries of the Questa caldera, defined boundaries of the shallow batholith, emplaced low in the volcanic sequence and in underlying Precambrian rocks. Paleomagnetic pole positions indicate that successively crystallised granitic plutons cooled through Curie temperatures during the time of caldera formation, initial regional extension, and rotational tilting of the volcanic rocks. Isotopic ages for most intrusions are indistinguishable from the volcanic rocks. These relations indicate that the batholithic complex broadly represents the source magma for the volcanic rocks, into which the Questa caldera collapsed, and that the magma was largely liquid during regional tectonic disruption. -from Author

  6. Field Mapping, LiDAR Analysis and Shallow Geophysical Methods Define the Geometry and Kinematics of the Leech River Fault, an Active Forearc Structure in Northern Cascadia

    NASA Astrophysics Data System (ADS)

    Graham, A. C.; Morell, K. D.; Leonard, L. J.; Regalla, C.; Levson, V.

    2016-12-01

    We use LiDAR imagery, shallow geophysical methods, and structural/geomorphic mapping to constrain the geometry and kinematics of the Leech River fault, an active crustal structure in the northern Cascadia outer forearc on southern Vancouver Island, British Columbia. Field mapping along a 20 km section of the fault reveals a 100 - 500 m wide zone comprising multiple sub-vertical brittle faults cutting through units on either side of the main regional lithologic contact. Electrical resistivity and GPR surveys across scarps identified in LiDAR imagery likewise reveal steeply dipping structures that appear to deform late Quaternary units to within 2 m of the surface locally. A maximum age of the most recent faulting of 6430 ± 20 14C yr B.P. is constrained by a radiocarbon date from a deformed fluvial terrace. Holocene activity on the Leech River fault indicates that major active crustal faults of the Cascadia forearc extend further north than has been previously recognized, and suggests that the Leech River fault is likely an extension of the active fault network defined in western Washington. The complex geometry of the fault zone and sub-vertical orientation of individual strands are suggestive of a strike-slip fault within a transpressive regime. Further analyses of measurements of fault plane orientations and slip sense indicators will determine whether the sense of slip on the Leech River fault is dextral or sinistral. Determining the kinematics of this prominent forearc structure is a key component in elucidating the nature of forearc deformation in northern Cascadia in response to both the ongoing bending of the Olympic orocline and the overall dynamics of the Cascadia subduction zone.

  7. Magnetic Fabric Investigations of the Sapinero Mesa and Fish Canyon Tuffs, Northern Part of the Southern Rocky Mountain Volcanic Field, Colorado

    NASA Astrophysics Data System (ADS)

    Harper, C.; Martin, M.; Geissman, J. W.

    2013-12-01

    Exposures of two laterally extensive ignimbrites in the northern part of the Southern Rocky Mountain Volcanic Field (SRMVF) allow examination of the emplacement mechanisms of these pyroclastic deposits as a function of deposition on irregular preexisting topography using magnetic fabric techniques. The Sapinero Mesa Tuff (28.19 × 0.03 Ma) was erupted from the San Juan/Uncompahgre Caldera Complex and the Fish Canyon tuff (ca. 28.02 × 0.16 Ma) was erupted from the La Garita caldera. These ignimbrites are major components of the SRMVF and were emplaced on highly irregular paleotopography. The Sapinero Mesa Tuff was emplaced directly on the late Eocene West Elk Breccia near and west of the Blue Mesa reservoir and directly on Precambrian crystalline rocks south of the Blue Mesa reservoir. The Fish Canyon Tuff was emplaced directly on Precambrian crystalline rocks south and southwest of Gunnison. Our study of these two ignimbrites is concentrated in the northern part of the SRMVF and examines how these deposits were emplaced on different topographic features. To date, a total of 16 sites in the Fish Canyon and Sapinero Mesa tuffs have been collected and analyzed for determination of magnetic fabrics through measurements of anisotropy of magnetic susceptibility (AMS). These samples are currently being analyzed for measurements of anisotropy of anhysteretic remanent magnetization (AARM). Initial analyses indicate transport directions that generally coincide with the inferred regional north-northwest transport direction. Additional sampling includes a greater spatial extent and a more focused method of collection with an emphasis on localities chosen with careful consideration of relationships to paleotopographic features present during emplacement of the ignimbrites. Specifically, we have selected linear features of varying scales with strikes that vary significantly from the regional, inferred transport directions. Our work provides a means to compare regional inferred

  8. Near-field co-seismic ionospheric response due to the northern Chile Mw 8.1 Pisagua earthquake on April 1, 2014 from GPS observations

    NASA Astrophysics Data System (ADS)

    Reddy, C. D.; Sunil, A. S.; González, G.; Shrivastava, Mahesh N.; Moreno, Marcos

    2015-11-01

    Large earthquakes can induce near and far-field ionospheric perturbations by direct/secondary acoustic and gravity waves through Lithosphere-Atmosphere-Ionosphere (LAI) coupling. We analyze co-seismic induced ionospheric TEC perturbations following the northern Chile Mw 8.1 Pisagua earthquake occurred on April 1, 2014. The continuous Global Positioning System (GPS) data at 15 sites from the Integrated Plate Boundary Observatory Chile (IPOC) and International GPS Service (IGS) GPS networks have been used in the present study. The nearest GPS site iqqe, ~98 km away from the epicenter, recorded the ionospheric disturbance 12 min after the event. The maximum co-seismic induced peak-to-peak TEC amplitude is ~1.25 TECU (1TECU=1016 electrons/m2), and the perturbations are confined to less than 1000 km radius around the epicenter. The observed horizontal velocity of TEC perturbations has been determined as ~1180 m/s. We could also discern the signatures of acoustic gravity waves (AGW) with velocity~650 m/s and frequency~2 mHz. The ionospheric signal components due to Rayleigh and/or Tsunami waves could not be observed. This contribution presents characteristics of near-field co-seismic ionospheric response due to the 2014 Pisagua earthquake.

  9. Virulence and polar tube protein genetic diversity of Nosema ceranae (Microsporidia) field isolates from Northern and Southern Europe in honeybees (Apis mellifera iberiensis).

    PubMed

    Van der Zee, Romee; Gómez-Moracho, Tamara; Pisa, Lennard; Sagastume, Soledad; García-Palencia, Pilar; Maside, Xulio; Bartolomé, Carolina; Martín-Hernández, Raquel; Higes, Mariano

    2014-08-01

    Infection of honeybees by the microsporidian Nosema ceranae is considered to be one of the factors underlying the increased colony losses and decreased honey production seen in recent years. However, these effects appear to differ in function of the climatic zone, the distinct beekeeping practices and the honeybee species employed. Here, we compared the response of Apis mellifera iberiensis worker bees to experimental infection with field isolates of N. ceranae from an Oceanic climate zone in Northern Europe (Netherlands) and from a Mediterranean region of Southern Europe (Spain). We found a notable but non-significant trend (P = 0.097) towards higher honeybee survival for bees infected with N. ceranae from the Netherlands, although no differences were found between the two isolates in terms of anatomopathological lesions in infected ventricular cells or the morphology of the mature and immature stages of the parasite. In addition, the population genetic survey of the N. ceranae PTP3 locus revealed high levels of genetic diversity within each isolate, evidence for meiotic recombination, and no signs of differentiation between the Dutch and Spanish populations. A cross-infection study is needed to further explore the differences in virulence observed between the two N. ceranae populations in field conditions. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. Risk of hematological malignancies associated with magnetic fields exposure from power lines: a case-control study in two municipalities of northern Italy

    PubMed Central

    2010-01-01

    Background Some epidemiologic studies have suggested an association between electromagnetic field exposure induced by high voltage power lines and childhood leukemia, but null results have also been yielded and the possibility of bias due to unmeasured confounders has been suggested. Methods We studied this relation in the Modena and Reggio Emilia municipalities of northern Italy, identifying the corridors along high voltage power lines with calculated magnetic field intensity in the 0.1-<0.2, 0.2-<0.4, and ≥ 0.4 microTesla ranges. We identified 64 cases of newly-diagnosed hematological malignancies in children aged <14 within these municipalities from 1986 to 2007, and we sampled four matched controls for each case, collecting information on historical residence and parental socioeconomic status of these subjects. Results Relative risk of leukemia associated with antecedent residence in the area with exposure ≥ 0.1 microTesla was 3.2 (6.7 adjusting for socioeconomic status), but this estimate was statistically very unstable, its 95% confidence interval being 0.4-23.4, and no indication of a dose-response relation emerged. Relative risk for acute lymphoblastic leukemia was 5.3 (95% confidence interval 0.7-43.5), while there was no increased risk for the other hematological malignancies. Conclusions Though the number of exposed children in this study was too low to allow firm conclusions, results were more suggestive of an excess risk of leukemia among exposed children than of a null relation. PMID:20353586

  11. Ground Penetrating Radar and Magnetic Investigations of Phreatomagmatic Tephra Rings in the San Francisco Volcanic Field, Northern Arizona

    NASA Astrophysics Data System (ADS)

    Marshall, A. M.; Kruse, S.; Macorps, E.; Charbonnier, S. J.

    2015-12-01

    Ground Penetrating Radar (GPR) can be a valuable geophysical tool for studying near-surface volcanic stratigraphy in areas where outcrops do not exist. Likewise, high resolution ground-based magnetic surveys have the potential to reveal significant features not exposed at the surface, especially in the case of small-volume basaltic volcanoes. Here we present the results of geophysical studies to investigate the eruptive history of deposits surrounding phreatomagmatic eruption sites, and why some may become magnetized. Magnetic surveys undertaken at basaltic phreatomagmatic sites suggest that some tuff rings carry no discernable magnetic signature, while others reveal slight to significant magnetic anomalies. Material deposited in the tephra ring could become magnetized through Thermal Remanent Magnetization - emplacement of magnetically susceptible material above 560° C. In this case tephra layers would need to be deposited in sufficient thickness to retain high temperatures long enough for the magnetic material to orient itself to the magnetic field. To test this hypothesis we examine GPR data collected at Rattlesnake Maar in the San Francisco Volcanic Field, Arizona, and we will collect GPR data at two other tephra rings in the same volcanic field. The first site, Sugarloaf Mountain, is an active quarry with excellent exposures of tephra ring stratigraphy. Although this site is rhyolitic in composition and not suitable for magnetic study, it is an excellent site to determine how well GPR reflectors correlate with actual stratigraphy. The second site, an un-named phreatomagmatic ring nearby, will then be studied by GPR and walking magnetic survey. GPR reflectors will be compared to depositional patterns defined in previous studies and correlated with magnetic survey results to determine if a correlation can be made - little to no magnetization where only thin units are recorded by GPR, and positive magnetization where thick units are recorded.

  12. Magnetic fabrics of diamagnetic rocks and the strain field associated with the Dead Sea Fault, northern Israel

    NASA Astrophysics Data System (ADS)

    Levi, Tsafrir; Weinberger, Ram

    2011-04-01

    In order to exploit the potential of AMS axes ( k1, k2, k3) and magnitudes as a tool to estimate the strain field around major faults, the AMS of calcite-bearing diamagnetic rocks that crop out next to the Dead Sea Fault (transform) (DSF) were measured. The calcite-bearing Bar Kokhba limestone contains magnetic fabrics due mainly to the diamagnetic phase, as indicated by the low iron content (<130 ppm), and strong negative susceptibilities of all the AMS principal axes. The magnetic fabrics are solely controlled by the alignment of c-axes of almost pure calcite crystals and help to assess the strain fields prevailing post-deposition and during the tectonic evolution of the DSF. Based on the AMS measurements of 146 diamagnetic samples as well as 65 paramagnetic samples, three groups of minimum k3 AMS axes are defined: (1) ˜NNE-plunging axis; (2) ˜NW-SE axis; and (3) ˜E-W axis. The latter two groups of k3 axes are aligned sub-parallel to Neogene to Pleistocene finite-strain axes inferred from meso-scale structures (i.e., folds, faults and veins) next to the DSF. This indicates that k3 axes of diamagnetic rocks can be excellent proxies for strain field directions around major faults. Differences in the degree of anisotropy P' (up to ˜2%) and in susceptibility difference Δ k (up to ˜0.2) of the diamagnetic rocks are related to differences in strain magnitudes. Based on the proximity of the studied outcrops to the fault traces, the values of these variables reflect the stored inelastic strain within the calcite matrix due to repeated faulting activity.

  13. A Field Study of Wall Furnace Venting and Coincident Exhaust Fan Usage in 16 Northern California Apartments

    SciTech Connect

    Singer, Brett C.; Less, Brennan D.; Delp, William W.; Brooks, Andrew; Cohn, Sebastian; Finn, Brian

    2016-09-01

    To inform efforts to improve combustion appliance testing in residential energy efficiency programs, we studied the frequency of coincident fan use and depressurization-induced downdrafting and spillage from atmospherically vented (i.e., natural draft) wall furnaces in airtight apartments. Indoor environmental conditions, heating appliance operation, use of exhaust fans, and cooking with stovetop or oven were monitored for approximately three weeks each in 16 apartment units in two buildings in Northern California. Apartments also were assessed using standard combustion appliance safety test methods and enhanced protocols. Monitoring occurred in February and March of 2016, with heating demand corresponding to 7.3 ± 0.5 heating degree-days at a 65ºF reference temperature. Most of the furnaces spilled combustion products when the apartments were depressurized in the “worst-case” challenge condition of all exhaust fans operating at their highest settings and all windows closed. Many also spilled under less challenging conditions (e.g., with kitchen exhaust fan on low and bathroom fan operating). On average, bathroom exhaust fans were operated 3.9% of monitored minutes (13.5% max), and cooking (burner or kitchen fan operation) occurred 4.6% of minutes (max 13.3%). Event lengths averaged 17 minutes (max 540) and 34 minutes (max 324), respectively. Their coincident operation averaged 0.34% of minutes (max 2.0%), with average event length of 13 minutes (max 92 minutes). This suggests that the operation of apartment units at or near the currently used worst-case challenge condition is quite rare. Wall furnace burners operated an average of 2.8% of minutes (max of 8.9%), with average burner cycle length of 14 minutes (max 162). Coincident bath fan use, cooking and wall furnace operation was very rare, occurring only a handful of times across all apartments. The highest rate was 0.075% of monitored minutes in one apartment, and the longest event length was 12 minutes

  14. Lithofacies and palynostratigraphy of some Cretaceous and Paleocene rocks, Surghar and Salt Range coal fields, northern Pakistan

    USGS Publications Warehouse

    Warwick, Peter D.; Javed, Shahid; Mashhadi, S. Tahir A.; Shakoor, Tariq; Khan, Asrar M.; Khan, A. Latif

    1995-01-01

    high concentrations of the environmentally sensitive element selenium (average 13.4 ppm (parts per million)), compared to concentrations from United States coals of similar rank. The Makarwal coal bed represents a paleopeat that formed during changing relative ground-water base levels. Relatively low base levels were associated with periods of slow clastic deposition and lateritic paleosol development, followed by relatively high base levels that coincided with increased runoff, marine flooding, and clastic sedimentation that buried the paleopeat of the Makarwal. These environments formed along the northwestern margin of the Indian subcontinent as it drifted northward through equatorial latitudes in the Tethys Sea. The Makarwal coal bed is thin or absent in the northern part of the range where the Lumshiwal and Hangu Formations are the thinnest. Such rapid lateral changes (over about 25 km) in formation thickness and the apparent change in relative ground-water base level indicate that tectonically induced subsidence rates varied across the Surghar Range and influenced the deposition of the rocks that compose the two formations.

  15. Extensive Analysis of GmFTL and GmCOL Expression in Northern Soybean Cultivars in Field Conditions

    PubMed Central

    Zhu, Jinlong; Lu, Mingyang; Chen, Fulu; Liu, Linpo; Xi, Zhang-Ying; Bachmair, Andreas; Chen, Qingshan; Fu, Yong-Fu

    2015-01-01

    The FLOWERING LOCUS T (FT) gene is a highly conserved florigen gene among flowering plants. Soybean genome encodes six homologs of FT, which display flowering activity in Arabidopsis thaliana. However, their contributions to flowering time in different soybean cultivars, especially in field conditions, are unclear. We employed six soybean cultivars with different maturities to extensively investigate expression patterns of GmFTLs (Glycine max FT-like) and GmCOLs (Glycine max CO-like) in the field conditions. The results show that GmFTL3 is an FT homolog with the highest transcript abundance in soybean, but other GmFTLs may also contribute to flower induction with different extents, because they have more or less similar expression patterns in developmental-, leaf-, and circadian-specific modes. And four GmCOL genes (GmCOL1/2/5/13) may confer to the expression of GmFTL genes. Artificial manipulation of GmFTL expression by transgenic strategy (overexpression and RNAi) results in a distinct change in soybean flowering time, indicating that GmFTLs not only impact on the control of flowering time, but have potential applications in the manipulation of photoperiodic adaptation in soybean. Additionally, transgenic plants show that GmFTLs play a role in formation of the first flowers and in vegetative growth. PMID:26371882

  16. Statistics of MLT wind field values derived from 11 years of common volume specular meteor observations in northern Norway

    NASA Astrophysics Data System (ADS)

    Chau, Jorge Luis; Stober, Gunter; Laskar, Fazlul; Hall, Chris M.; Tsutsumi, Masaki

    2016-04-01

    Traditionally mean values of the mesosphere and lower thermosphere winds over the radar volume are obtained using monostatic specular meteor radars. Such observing volume consist of a few hundreds of kilometers in radius. Moreover the differences between measured radial velocities and the expected radial velocities from the measured mean winds are used to derive properties of gravity wave momentum fluxes. Recently, Stober and Chau [2015] have proposed to use a multi-static approach to retrieve horizontally resolved wind fields, where most of the radar volume is observed from different viewing angles. Similar results could be obtained if measurements from close-by monostatic systems are combined. In this work we present the results of the derived wind fields from combining specular meteor radar data between 2004 and 2015 from the Trømso (19.22oW, 69.58oN) and Andenes (16.04oW, 69.27oN) radar systems. Among the directly estimated values are the mean winds and the horizontal and vertical gradients of the zonal and meridional winds. Combining the horizontal gradients, the horizontal divergence, relative vorticity, shear and deformation are derived. The seasonal and annual variability of these parameters are presented and discussed, as well as the planetary wave, tidal, and gravity wave information embedded in these new parameters.

  17. The Oldest Known Caldera Associated with the Yellowstone Hotspot: New Geologic Mapping, Geochemistry, and 40Ar/39Ar Geochronology for the Northern McDermitt Volcanic Field, Northern Nevada and Southeastern Oregon

    NASA Astrophysics Data System (ADS)

    Benson, T. R.; Mahood, G. A.

    2015-12-01

    McDermitt Volcanic Field (MVF) of Nevada and Oregon is one of three major caldera centers associated with Mid-Miocene Steens/Columbia River flood basalts. Pioneering geologic mapping of MVF by Rytuba and McKee (1984) and subsequent work established four main ignimbrites within the field. Our new 40Ar/39Ar ages (FCT=28.02 Ma) are 16.41±0.02 (±2σ) Ma for Tuff of Oregon Canyon, 16.35±0.04 Ma for Tuff of Trout Creek Mountains, 16.30±0.04 Ma for Tuff of Long Ridge, and 15.56±0.08 Ma for Tuff of Whitehorse Creek. We have mapped two previously unrecognized overlapping calderas that we interpret as sources for Tuff of Oregon Canyon and Tuff of Trout Creek. These ~20-km diameter calderas lie north of the well-known McDermitt Caldera; a smaller 7-km caldera that formed on eruption of the Tuff of Whitehorse Creek is nested within them. Argon ages and geochemistry of alkali rhyolite lava domes in the northern MVF define two populations: ~16.6-16.3 Ma associated with the newly recognized calderas, and ~15.5-15.3 Ma outlining the margins of the younger Whitehorse Caldera. Consistent with both ignimbrites erupting from the same evolving magma system, the high-silica alkali rhyolite Tuff of Oregon Canyon lies on compositional trends defined by the Tuff of Trout Creek, which is zoned from a moderately crystal-rich high-silica alkali rhyolite to a strongly porphyritic low-silica alkali rhyolite. They both are distinguished from the Tuff of Long Ridge from McDermitt Caldera by their higher Zr/Rb, and relatively high FeO* concentrations distinguish all MVF ignimbrites from ignimbrites from the nearby High Rock Caldera Complex, where the oldest caldera formed on eruption of the Idaho Canyon Tuff at 16.38±0.02 Ma (Coble and Mahood, in review). The Tuff of Trout Creek rests conformably on the Tuff of Oregon Canyon west and southwest of the calderas, where they overlie a thick stack of Steens Basalt lavas. To the east and southeast the two ignimbrites are separated by as much as

  18. Modifications to the Soil-Vegetation-Atmosphere Continuum by Hedgerows - Observations from a field site in Northern England

    NASA Astrophysics Data System (ADS)

    Coates, Victoria; Pattison, Ian

    2016-04-01

    UK farming practices have changed significantly over the past 100 years. This is evident in arable fields, where the use of larger machinery has led to the removal of hedgerows. In the River Skell catchment, in Yorkshire, UK this has led to a doubling in field size since 1892. The national-wide change is responsible for longer slope lengths, increased runoff velocities and greater potential for connectivity, which may be responsible for an increase in flood risk at the catchment scale. However there is a lack of physical evidence to support this theory. Hedgerows are a widespread, man-made boundary feature in the rural UK landscape. They play an important ecological role in providing shelter, changing the local climate, reducing erosion and have a strong influence on local soil properties. Their impact on hydrology has not been widely studied but it is hypothesised that their presence could alter soil moisture levels and the soil structure, therefore affecting runoff. This paper presents observations of a hedgerow on the Soil-Vegetation-Atmosphere Continuum, through 15 months field monitoring conducted in the River Skell catchment. Firstly, to assess soil moisture levels TDR probes were installed at different depths and distances from the hedgerow. To assess the soil quality and therefore its infiltration capacity, soil cores were collected to determine soil horizons and root density. Also, laboratory tests were undertaken to determine the soil type and the porosity. Secondly, to assess the physical impact of the hedgerow plant on the partitioning of rainfall, gauges were installed to capture the spatial distribution of rainfall, along a transect perpendicular to the hedgerow, as well as stemflow. Throughfall gauges were also installed within the hedgerow and leaf area index calculated. Thirdly, to assess the impact of the hedgerow on the micro-climate, temperature sensors and four leaf wetness sensors were installed to determine evapotranspiration and interception

  19. Potential Field, Geoelectrical and Reflection Seismic Investigations for Massive Sulphide Exploration in the Skellefte Mining District, Northern Sweden

    NASA Astrophysics Data System (ADS)

    Tavakoli, Saman; Dehghannejad, Mahdieh; García Juanatey, María de los Ángeles; Bauer, Tobias E.; Weihed, Pär; Elming, Sten-Åke

    2016-12-01

    Multi-scale geophysical studies were conducted in the central Skellefte district (CSD) in order to delineate the geometry of the upper crust (down to maximum 4.5 km depth) for prospecting volcanic massive sulphide (VMS) mineralization. These geophysical investigations include potential field, resistivity/induced polarization (IP), reflection seismic and magnetotelluric (MT) data which were collected between 2009 and 2010. The interpretations were divided in two scales: (i) shallow ( 1.5 km) and (ii) deep ( 4.5 km). Physical properties of the rocks, including density, magnetic susceptibility, resistivity and chargeability, were also used to improve interpretations. The study result delineates the geometry of the upper crust in the CSD and new models were suggested based on new and joint geophysical interpretation which can benefit VMS prospecting in the area. The result also indicates that a strongly conductive zone detected by resistivity/IP data may have been missed using other geophysical data.

  20. Low-molecular weight hydrocarbons in vent fluids from the Main Endeavour Field, northern Juan de Fuca Ridge

    NASA Astrophysics Data System (ADS)

    Cruse, Anna M.; Seewald, Jeffrey S.

    2010-11-01

    Despite its location on sediment-free basalt, vent fluids from the Main Endeavour Field (MEF) contain chemical species that indicate fluids have interacted with sediments during circulation. We report on the distribution and isotopic abundances of organic compounds ( C1- C3 alkanes and alkenes, benzene and toluene) in fluids collected from the Main Endeavour Field (MEF) in July, 2000, to understand the processes that regulate their abundances and characterize fluid sources. Aqueous organic compounds are derived from the thermal alteration of sedimentary organic matter and subsequently undergo further oxidation reactions during fluid flow. Fluid:sediment mass ratios calculated using ΣNH 4 concentrations indicate that the sediments are distal to the MEF, resulting in a common reservoir of fluids for all of the vents. Following the generation from sediment alteration, aqueous organic compounds undergo secondary alteration reactions via a stepwise oxidation reaction mechanism. Alkane distributions and isotopic compositions indicate that organic compounds in MEF fluids have undergone a greater extent of alteration as compared to Middle Valley fluids, either due to differences in subsurface redox conditions or the residence time of fluids at subsurface conditions. The distributions of the aromatic compounds benzene and toluene are qualitatively consistent with the subsurface conditions indicated by equilibration of aqueous alkanes and alkanes. However, benzene and toluene do not achieve chemical equilibrium in the subsurface. Methane and CO 2 also do not equilibrate chemically or isotopically at reaction zone temperatures, a likely result of an insufficient reaction time after addition of CO 2 from magmatic sources during upflow. The organic geochemistry supports the assumption that the sediments with which MEF fluids interact has the same composition as sediments present in Middle Valley itself, and highlight differences in subsurface reaction zone conditions and fluid

  1. [Responses of soil microbial carbolic metabolism characteristics to home-field advantage of leaf litter decomposition in Liaoheyuan Nature Reserve of northern Hebei Province, China].

    PubMed

    Li, Tian-yu; Kang, Feng-feng; Han, Hai-rong; Gao, Jing; Song, Xiao-shuai; Yu, Shu

    2015-07-01

    Using litter bag method, we studied the responses of soil microbial biomass carbon (MBC), microbial respiration (MR) and microbial metabolic quotient (qCO2) in 0-5 cm, 5-10 cm and 10-20 cm soil layers to home-field advantage of Betula platyphlla and Quercus mongolica leaf litter decomposition in Liaoheyuan Nature Reserve, northern Hebei Province. The results showed that the contents of MBC in Betula platyphila and Quercus mongolica leaf litter treatments in home environment (Bh and Qh treatments) were significant higher than that in B. platyphlla and Q. mongolica leaf litter treatments in non-home environment (Ba and Qa treatments). There was no significant difference in MR between home and non-home environments. Response degree of MBC and MR to home-field advantage of different litter decomposition was inconsistent. The MBC of the different soil layers in Qa treatment fell by 39.6%, 34.9% and 33.5% compared to Qh treatment, respectively, and that in B. platyphlla treatment was decreased by 31.6%, 27.1% and 17.0%, respectively. MR of the different soil layers in Qa treatment accounted for 96.3%, 92.4% and 83.7% of Qh treatment, respectively, while MR in B. platyphila treatment was 99. 4%, 97. 3% and 101.3%, respectively. In contrast to MBC, qCO2 in soil showed a reverse pattern. Our study suggested that rich nutrients in soil enhanced microbial activity and weakened the conflict of nutrient uptake between plants and microorganisms, which led to the result that MBC and qCO2 had an obvious response to home-field advantage of litter decomposition, when litter decomposed in its home environment. There was a weak response between MR and home-field advantage of litter decomposition, because of influence of soil temperature, water content and their interaction. Furthermore, MBC, MR and qCO2 had a higher response degree to home-field advantage of Q. mongolica litter than B. platyphila litter, since lower quality litter exhibited higher home-field advantage of litter

  2. Intermediate composition magma production in an intracontinental setting: Unusual andesites and dacites of the mid-Miocene Santa Rosa-Calico volcanic field, Northern Nevada

    NASA Astrophysics Data System (ADS)

    Brueseke, Matthew E.; Hart, William K.

    2009-11-01

    The mid-Miocene Santa Rosa-Calico volcanic field (SC) of northern Nevada provides an outstanding example of the role open-system magmatic processes play in producing calc-alkaline and tholeiitic andesite-dacite magmas in an intracontinental setting. SC volcanism commenced at ˜ 16.7 Ma and is associated with the initial manifestations of the Yellowstone hotspot, the Columbia River-Steens flood basalt event(s), and the formation of the Northern Nevada rift. Locally a diverse package of magmatic products ranging from tholeiitic basalt to high-Si rhyolite was produced during an ˜ 2 myr duration. Within this package are the products of at least four distinct intermediate composition magmatic systems that may represent as much as 40% of the SC volcanic pile. These help differentiate the SC from contemporaneous Oregon Plateau volcanic fields (e.g. McDermitt, Lake Owyhee, Northwest Nevada) that are dominated by bimodal basalt-rhyolite assemblages. All SC intermediate units are characterized by textural and mineralogic complexities including xenoliths and xenocrysts of local crust and crystal clots of plagioclase ± clinopyroxene ± orthopyroxene ± oxide. SC intermediate units are dominantly tholeiitic, but include lava flows with transitional to calc-alkaline affinities. Relative to locally erupted Steens Basalt, SC intermediate lava flows have similar elemental enrichments and depletions, but dissimilar Sr and Nd isotopic compositions. These isotopic differences, coupled with the abundant disequilibrium features and variable incompatible element ratios, indicate that open system magmatic processes played a major role in the genesis of the intermediate units. SC silicic magmas were produced primarily via upper crustal melting of chemically and isotopically heterogeneous Cretaceous granitoid. Interaction between fractionating mafic Steens flood basalt magmas and the more evolved crustal melts ± assimilation of local upper crust provides a general template for the

  3. Laboratory and field evaluations of chemical and plant-derived potential repellents against Culicoides biting midges in northern Spain.

    PubMed

    González, M; Venter, G J; López, S; Iturrondobeitia, J C; Goldarazena, A

    2014-12-01

    The efficacy of 23 compounds in repelling Culicoides biting midges (Diptera: Ceratopogonidae), particularly Culicoides obsoletus (Meigen) females, was determined by means of a Y-tube olfactometer. The 10 most effective compounds were further evaluated in landing bioassays. The six most promising compounds (including chemical and plant-derived repellents) were evaluated at 10% and 25% concentrations in field assays using Centers for Disease Control (CDC) light traps. At least three compounds showed promising results against Culicoides biting midges with the methodologies used. Whereas olfactometer assays indicated DEET at 1 µg/µL to be the most effective repellent, filter paper landing bioassays showed plant-derived oils to be better. Light traps fitted with polyester mesh impregnated with a mixture of octanoic, decanoic and nonanoic fatty acids at 10% and 25% concentrations collected 2.2 and 3.6 times fewer midges than control traps and were as effective as DEET, which is presently considered the reference standard insect repellent. The best plant-derived product was lemon eucalyptus oil. Although these have been reported as safe potential repellents, the present results indicate DEET and the mixture of organic fatty acids to be superior and longer lasting. © 2014 The Royal Entomological Society.

  4. In Situ Nitrogen Mineralization, Nitrification, and Ammonia Volatilization in Maize Field Fertilized with Urea in Huanghuaihai Region of Northern China

    PubMed Central

    Zhang, Xuelin; Wang, Qun; Xu, Jun; Gilliam, Frank S.; Tremblay, Nicolas; Li, Chaohai

    2015-01-01

    Nitrogen (N) fertilization potentially affects soil N mineralization and leaching, and can enhance NH3 volatilization, thus impacting crop production. A fertilizer experiment with five levels of N addition (0, 79, 147, 215 and 375 kg N ha-1) was performed in 2009 and 2010 in a maize field in Huanghuaihai region, China, where > 300 kg N ha-1 has been routinely applied to soil during maize growth period of 120 days. Responses of net N mineralization, inorganic N flux (0–10cm), NH3 volatilization, and maize yield to N fertilization were measured. During the growth period, net N mineralization and nitrification varied seasonally, with higher rates occurring in August and coinciding with the R1 stage of maize growth. Soil NO3−-N contributed to more than 60% of inorganic N flux during maize growth. Cumulative NH3 volatilization increased with N additions, with total NH3 volatilization during maize growth accounting for about 4% of added N. Relative to the control, mean maize yield in the fertilizer treatments increased by 17% and 20% in 2009 and 2010, respectively. However, grain yield, aboveground biomass, and plant N accumulation did not increase with added N at levels > 215 kg N ha-1. These results suggest that the current N rate of 300 kg N ha-1 is not only excessive, but also reduces fertilizer efficacy and may contribute to environmental problems such as global warming and eutrophication of ground water and streams. PMID:25635864

  5. Fault geometry and mechanics of marly carbonate multilayers: An integrated field and laboratory study from the Northern Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Giorgetti, C.; Collettini, C.; Scuderi, M. M.; Barchi, M. R.; Tesei, T.

    2016-12-01

    Sealing layers are often represented by sedimentary sequences characterized by alternating strong and weak lithologies. When involved in faulting processes, these mechanically heterogeneous multilayers develop complex fault geometries. Here we investigate fault initiation and evolution within a mechanical multilayer by integrating field observations and rock deformation experiments. Faults initiate with a staircase trajectory that partially reflects the mechanical properties of the involved lithologies, as suggested by our deformation experiments. However, some faults initiating at low angles in calcite-rich layers (θi = 5°-20°) and at high angles in clay-rich layers (θi = 45°-86°) indicate the important role of structural inheritance at the onset of faulting. With increasing displacement, faults develop well-organized fault cores characterized by a marly, foliated matrix embedding fragments of limestone. The angles of fault reactivation, which concentrate between 30° and 60°, are consistent with the low friction coefficient measured during our experiments on marls (μs = 0.39), indicating that clay minerals exert a main control on fault mechanics. Moreover, our integrated analysis suggests that fracturing and faulting are the main mechanisms allowing fluid circulation within the low-permeability multilayer, and that its sealing integrity can be compromised only by the activity of larger faults cutting across its entire thickness.

  6. In situ nitrogen mineralization, nitrification, and ammonia volatilization in maize field fertilized with urea in Huanghuaihai region of northern China.

    PubMed

    Zhang, Xuelin; Wang, Qun; Xu, Jun; Gilliam, Frank S; Tremblay, Nicolas; Li, Chaohai

    2015-01-01

    Nitrogen (N) fertilization potentially affects soil N mineralization and leaching, and can enhance NH3 volatilization, thus impacting crop production. A fertilizer experiment with five levels of N addition (0, 79, 147, 215 and 375 kg N ha(-1)) was performed in 2009 and 2010 in a maize field in Huanghuaihai region, China, where > 300 kg N ha(-1) has been routinely applied to soil during maize growth period of 120 days. Responses of net N mineralization, inorganic N flux (0-10 cm), NH3 volatilization, and maize yield to N fertilization were measured. During the growth period, net N mineralization and nitrification varied seasonally, with higher rates occurring in August and coinciding with the R1 stage of maize growth. Soil NO3(-)-N contributed to more than 60% of inorganic N flux during maize growth. Cumulative NH3 volatilization increased with N additions, with total NH3 volatilization during maize growth accounting for about 4% of added N. Relative to the control, mean maize yield in the fertilizer treatments increased by 17% and 20% in 2009 and 2010, respectively. However, grain yield, aboveground biomass, and plant N accumulation did not increase with added N at levels > 215 kg N ha(-1). These results suggest that the current N rate of 300 kg N ha(-1) is not only excessive, but also reduces fertilizer efficacy and may contribute to environmental problems such as global warming and eutrophication of ground water and streams.

  7. The anatomy of a cinder cone: preliminary paleomagnetic, rock magnetic, structural, and petrologic data from the La Cienega volcano, Cerros del Rio volcanic field, northern New Mexico

    NASA Astrophysics Data System (ADS)

    Petronis, M. S.; Foucher, M.; Lineline, J.; Van Wyk de Vries, B.

    2011-12-01

    The Cerros del Rio volcanic field is one of several middle Pliocene to Pleistocene basaltic volcanic fields of the axial Rio Grande Rift in central and northern New Mexico. It is a monogenetic volcanic field that comprises about 60 cinder-spatter cones, occupies ~ 700 km2, and ranges in age from 2.7 Ma to 1.1 Ma. Eruptive centers are typically central vent volcanoes, ranging from low-relief shields to steep-sided, breached cinder and spatter cone remnants. They represent short eruptive events that likely were derived from rapidly evolving reservoir-conduit systems. Mining activity has exposed the volcanic plumbing system of the Cienega Mine cinder cone, just west of Santa Fe, NM. Here, geologists from France and USA have been investigating the exposed roots of this eviscerated Pliocene volcano to investigate magma conduit geometry, magma flow structures, and eruption patterns. We are testing models for magma transport and volcano construction using a variety of field and laboratory tools. Common models of volcanic construction envision the magma feeder as a dike or pipe-like conduit transporting molten rock from a deep reservoir to the eruptive vent. We posit that small volcanic pluming systems are inherently more complex and actually involve numerous feeder geometries throughout the volcano lifespan. Our preliminary work suggests that the simple exteriors of some cinder cones hide a long life and complex history, both of which would change the appreciation of the related volcanic hazards in active systems. The Cienega Mine cinder cone consists of several meter- to decimeter-wide intrusions that connect to eruptive centers. These intrusions show a continuity of brittle to ductile structures from their margins to interiors. We have collected samples across each intrusion as well as along strike for anisotropy of magnetic susceptibility (AMS) and petrographic analysis in order to establish magma flow patterns. AMS results yield a remarkably consistent dataset that

  8. Dissolved Carbon Species in Diffuse and Focused Flow Hydrothermal Vents at the Main Endeavour Field, Northern Juan de Fuca Ridge

    NASA Astrophysics Data System (ADS)

    Foustoukos, D. I.; Seyfried, W. E.; Ding, K.; Pester, N. J.

    2006-12-01

    The magmatic and tectonic event of 1999 had a significant impact on the chemical composition of vent fluids issuing from the Main Endeavour Field (MEF), Juan de Fuca Ridge. Here, we report dissolved concentrations of H2, CO2, CO and C1-C3 alkanes measured in low and high-temperature hydrothermal fluids collected in August 2005 during an RV Atlantis/DSV Alvin expedition at MEF. In comparison with time series data, temperatures of the 2005 vent fluids were slightly lower than those recorded in the aftermaths of the tectonic event of 1999. The possible cooling of the hydrothermal subseafloor reaction zone is consistent with the observed increase in dissolved Cl to pre-1999 values. Converging compositional trends to pre-1999 conditions are also suggested for dissolved CO2 concentrations (~20 mmol/kg) in Puffer, Sully, Bastille and S&M vent fluids. In these focused flow and high-temperature vent fluids, dissolved CO2 is in thermodynamic equilibrium with CO(aq). The systematics of organic species in diffuse flow fluids, however, appears to be closely related to processes occurring within the near-seafloor environment. For example, excess CO(aq) observed in the diffuse flow fluids at Easter Island is attributed to sluggish CO- CO2(aq) equilibria at low temperatures, suggesting hydrothermal circulation of short-residence times. Short-lived hydrothermal circulation is further supported by the nearly identical C1/(C2+C3) ratios between focused and diffuse flow fluids. Furthermore, alkane distribution in the MEF diffuse flow fluids suggests direct mixing between seawater and hydrothermal fluid with minimal biological inputs, in contrast with the greater effect of microbial methanogenesis proposed in other ridge-crest hydrothermal environments. Thus, the coupling of CO2(aq)-CO(aq) redox equilibrium with dissolved carbon species in low- temperature vent fluids could provide a better understanding of the effect of subsurface microbial communities upon the composition of mid

  9. Carbon sequestration strategies for crop- and grasslands evaluated in long-term field experiments in Northern Europe

    NASA Astrophysics Data System (ADS)

    Kätterer, Thomas; Bolinder, Martin; Börjesson, Gunnar; Kirchmann, Holger

    2013-04-01

    Improved management of grass- and croplands is a win-win strategy resulting in both increased soil fertility and carbon sequestration. We quantified the effect of N fertilization, organic amendments and ley-arable rotations versus continuous annual cropping systems on soil carbon stocks by analyzing data from long-term field experiments in Nordic countries. Increasing net primary production was found to be the main driver for higher soil carbon storage. Mineral N fertilization increased soil carbon stocks by about 1-2 kg C ha-1 for each kg of N applied to cropland. Ley-arable rotations, being a combination of annual and perennial crops, are expected to have C stocks intermediate between continuous grass- and croplands. A summary of data from 15 long-term sites showed that on average 0.5 Mg ha-1 yr-1 (range 0.3 to 1.1; median 0.4 Mg ha-1 yr-1) more carbon was retained in soils in ley-arable compared to exclusively annual systems, depending on species composition, management, soil depth and the duration of the studies. We also quantified the effect of organic amendments on soil carbon stocks. Retention factors calculated for straw, manure, sawdust, peat, sewage sludge and composted household waste varied widely from about 15% for above-ground crop residues to about 90% for composted household waste. We also emphasize that increased soil carbon stocks not always lead to carbon sequestration of atmospheric CO2 and discuss misunderstandings related to mitigation options earlier proposed for carbon sequestration such as organic farming, manure application, residue handling or application of biochar. Finally, the consequences of different land use and management are discussed, taking into account two critical boundaries - the limited area of agricultural land on Earth and requirements to produce sufficient food, fibres and energy for a growing population.

  10. A high-resolution model of the external and induced magnetic field at the Earth's surface in the Northern Hemisphere

    NASA Astrophysics Data System (ADS)

    Shore, R. M.; Freeman, M. P.; Wild, J. A.; Gjerloev, J. W.

    2017-02-01

    We describe a method of producing high-resolution models of the Earth's combined external and induced magnetic field using the method of empirical orthogonal functions (EOFs) applied to the SuperMAG archive of ground-based magnetometer data. EOFs partition the variance of a system into independent modes, allowing us to extract the spatiotemporal patterns of greatest dynamical importance without applying the a priori assumptions of other methods (such as spherical harmonic analysis, parameterized averaging, or multivariate regression). We develop an approach based on that of Beckers and Rixen (2003) and use the EOF modes to infill missing data in a self-consistent manner. Applying our method to a north polar case study spanning February 2001 (chosen for its proximity to solar maximum and good data coverage), we demonstrate that 41.7% and 9.4% of variance is explained by the leading two modes, respectively, describing the temporal variations of the disturbance polar types 2 and 1 (DP2 and DP1) patterns. A further 14.1% of variance is explained by four modes that describe separate aspects of the motion of the DP1 and DP2 systems. Thus, collectively over 65% of variance is described by the leading six modes and is attributable to DP1 and DP2. This attribution is based on inspection of the spatial morphology of the modes and analysis of the temporal variation of the mode amplitudes with respect to solar wind measures and substorm occurrence. This study is primarily a demonstration of the technique and a prelude to a model spanning the full solar cycle.

  11. Origin of metaluminous and alkaline volcanic rocks of the Latir volcanic field, northern Rio Grande rift, New Mexico

    USGS Publications Warehouse

    Johnson, C.M.; Lipman, P.W.

    1988-01-01

    Volcanic rocks of the Latir volcanic field evolved in an open system by crystal fractionation, magma mixing, and crustal assimilation. Early high-SiO2 rhyolites (28.5 Ma) fractionated from intermediate compositionmagmas that did not reach the surface. Most precaldera lavas have intermediate-compositions, from olivine basaltic-andesite (53% SiO2) to quartz latite (67% SiO2). The precaldera intermediate-composition lavas have anomalously high Ni and MgO contents and reversely zoned hornblende and augite phenocrysts, indicating mixing between primitive basalts and fractionated magmas. Isotopic data indicate that all of the intermediate-composition rocks studied contain large crustal components, although xenocrysts are found only in one unit. Inception of alkaline magmatism (alkalic dacite to high-SiO2 peralkaline rhyolite) correlates with, initiation of regional extension approximately 26 Ma ago. The Questa caldera formed 26.5 Ma ago upon eruption of the >500 km3 high-SiO2 peralkaline Amalia Tuff. Phenocryst compositions preserved in the cogenetic peralkaline granite suggest that the Amalia Tuff magma initially formed from a trace element-enriched, high-alkali metaluminous magma; isotopic data suggest that the parental magmas contain a large crustal component. Degassing of water- and halogen-rich alkali basalts may have provided sufficient volatile transport of alkalis and other elements into the overlying silicic magma chamber to drive the Amalia Tuff magma to peralkaline compositions. Trace element variations within the Amalia Tuff itself may be explained solely by 75% crystal fractionation of the observed phenocrysts. Crystal settling, however, is inconsistent with mineralogical variations in the tuff, and crystallization is thought to have occurred at a level below that tapped by the eruption. Spatially associated Miocene (15-11 Ma) lavas did not assimilate large amounts of crust or mix with primitive basaltic magmas. Both mixing and crustal assimilation processes

  12. Field evaluation of G10, a celery (Apium graveolens)-based topical repellent, against mosquitoes (Diptera: Culicidae) in Chiang Mai province, northern Thailand.

    PubMed

    Tuetun, B; Choochote, W; Pongpaibul, Y; Junkum, A; Kanjanapothi, D; Chaithong, U; Jitpakdi, A; Riyong, D; Wannasan, A; Pitasawat, B

    2009-02-01

    The potential of G10, a celery (Apium graveolens)-based topical product, as a repellent against natural mosquito populations was evaluated in comparison to commercial (Insect Block 28) and standard (25% DEET) repellents in Chiang Mai province, northern Thailand. These repellent products afforded encouragingly excellent personal protection against a broad range of mosquito species belonging to various genera, including Aedes, Anopheles, Armigeres, Culex, and Mansonia. No mosquito bite was observed on the volunteers treated with G10 and Insect Block 28 throughout the field study, whereas two species, i.e., six A. barbirostris and two A. subalbatus, came to bite or land on 25% DEET-treated volunteers. Thus, it can be concluded that while G10 and Insect Block 28 exhibited similarly powerful repellent activities with complete (100%) protection, 25% DEET was effective in minimizing bites with 99.68% protection. G10 formula was also studied for physical properties and biological stability after being kept under two conditions; a heating and cooling cycle, and varying temperature and time storage. Most samples of stored G10 not only demonstrated a similarity in appearance and physical properties, but also provided comparable repellency to that of the fresh preparation. These findings encourage commercial development of G10 formula as an alternative to conventional synthetic repellents.

  13. Tectonic inversion and magmatism in the Lautaro Basin, northern Chile, Central Andes: A comparative approach from field data and analog models

    NASA Astrophysics Data System (ADS)

    Martínez, Fernando; Bonini, Marco; Montanari, Domenico; Corti, Giacomo

    2016-03-01

    We present the results of a series of analog models addressing the relationships between tectonic inversion and magmatism, taking the Lautaro Basin in northern Chile (27-28° S), Central Andes as a natural case. The experiments consisted of extension and orthogonal shortening of sand-silicone models to reproduce the tectonic inversion of a previous extensional system synchronous with the emplacement of analog magma. We analyzed how the variation in the rate of magma intrusion, shortening, and syn-compressive sedimentation may affect the final configuration of an inverted system, and the results were compared with field observations. Our results showed that (i) folding of syn-rift deposits and increased steepness of the master faults accommodate the shortening of the extensional system, (ii) magmatic intrusions condition the final geometries (top view and cross-section) of inverted normal faults in the models and in the Lautaro Basin, (iii) magma tends to migrate preferentially along the inverted faults, and accumulates beneath the faults and in the core of the inversion anticlines, (iv) the syn-inversion magmatism may indicate the migration pathways, which favor major lubrication and slip on the structures during their reactivation.

  14. Unusual 5 m E region field-aligned irregularities observed from Northern Germany during the magnetic storm of 17 March 2015

    NASA Astrophysics Data System (ADS)

    Chau, Jorge L.; St.-Maurice, Jean-Pierre

    2016-10-01

    Coherent E region echoes were observed during the 17 March 2015 storm at midlatitudes by multistatic wide field of view radars operating in northern Germany. Two of the stations operated in a monostatic configuration, while one link was set in bistatic mode. Interferometry made it feasible to locate the targets. While the radars were built to measure mesospheric winds from specular meteor echoes, the storm was so intense that it allowed them to observe auroral E region echoes for more than 4 h. All stations detected numerous examples of narrow spectra with slow (≈180 m/s) and fast (up to 1600 m/s) Doppler velocities. The target speeds were much faster than the Doppler velocities for the slow narrow echoes (more than 800 m/s versus 180 m/s) but comparable to the observed Doppler shift for the 1500 m/s narrow fast types. The narrow types came from localized horizontal structures 50 to 80 km wide in range. The fast narrow types came from the upper part of the altitudes associated with Farley-Buneman waves. The slow narrow structures were typically from altitudes lower than 100 km. Unexpectedly, the great majority of the echoes associated with more ordinary ion acoustic turbulence had a positive Doppler shift and came from the east. A companion paper uses these new observations to reevaluate the origin of the narrow echoes and of the asymmetry in the counts. Irrespective of the generation mechanisms, our observations indicate that a combination of unusually large electric field and strong precipitation is needed to produce the unusual echoes.

  15. Passive aerobic treatment of net-alkaline, iron-laden drainage from a flooded underground anthracite mine, Pennsylvania, USA

    USGS Publications Warehouse

    Cravotta, C.A.

    2007-01-01

    This report evaluates the results of a continuous 4.5-day laboratory aeration experiment and the first year of passive, aerobic treatment of abandoned mine drainage (AMD) from a typical flooded underground anthracite mine in eastern Pennsylvania, USA. During 1991-2006, the AMD source, locally known as the Otto Discharge, had flows from 20 to 270 L/s (median 92 L/s) and water quality that was consistently suboxic (median 0.9 mg/L O2) and circumneutral (pH ??? 6.0; net alkalinity >10) with moderate concentrations of dissolved iron and manganese and low concentrations of dissolved aluminum (medians of 11, 2.2, and <0.2 mg/L, respectively). In 2001, the laboratory aeration experiment demonstrated rapid oxidation of ferrous iron (Fe 2+) without supplemental alkalinity; the initial Fe2+ concentration of 16.4 mg/L decreased to less than 0.5 mg/L within 24 h; pH values increased rapidly from 5.8 to 7.2, ultimately attaining a steady-state value of 7.5. The increased pH coincided with a rapid decrease in the partial pressure of carbon dioxide (PCO2) from an initial value of 10 -1.1atm to a steady-state value of 10-3.1atm. From these results, a staged aerobic treatment system was conceptualized consisting of a 2 m deep pond with innovative aeration and recirculation to promote rapid oxidation of Fe2+, two 0.3 m deep wetlands to facilitate iron solids removal, and a supplemental oxic limestone drain for dissolved manganese and trace-metal removal. The system was constructed, but without the aeration mechanism, and began operation in June 2005. During the first 12 months of operation, estimated detention times in the treatment system ranged from 9 to 38 h. However, in contrast with 80-100% removal of Fe2+ over similar elapsed times during the laboratory aeration experiment, the treatment system typically removed less than 35% of the influent Fe2+. Although concentrations of dissolved CO2 decreased progressively within the treatment system, the PCO2 values for treated effluent

  16. Assessment of Temporal and spatial variability of soil hydraulic properties and its implications on soil water content predictions for a maize field in Northern Italy

    NASA Astrophysics Data System (ADS)

    Feki, Mouna; Ravazzani, Giovanni; Ceppi, Alessandro; Mancini, Marco

    2016-04-01

    Use of hydrological models to simulate water movement from soil surface to groundwater requires intensive, time consuming and expensive soil related parameters collection, such as, water retention curve (WRC) parameters and hydraulic conductivity (K).Typically, soils to be characterized, , exhibit large variations in space and time as well during the cropping cycle, due to biological processes and agricultural management practices : tillage , irrigation , fertilization and harvest. Soil properties are subjected to diverse physical and chemical changes that leads to a non-stability in term of water and chemical movements within the soil as well to the groundwater. The aim of this study is to assess the variability of soil hydraulic properties dynamics over a cropping cycle. The study site is a surface irrigated Maize field (typical in this area) located in Secugnago (45°13'31.70'' N, 9°36'26.82 E), in Northern Italy-Lombardy region. The field belongs to the Consortium Muzza Bassa Lodigiana, within which meteorological data together with soil moisture were monitored during the cropping season of 2015 . To investigate soil properties variations, both measurements in the field and laboratory tests on both undisturbed and disturbed collected samples were performed. Soil samples were taken from different locations within the study area and at different depths( 0cm , 20cm and 40cm) as well at different growth stages of the plant ,after irrigation events or tillage and as well after harvest. During three measuring campaigns, for each soil samples several parameters were monitored (Organic matter , bulk density) together with soil-water related parameters (Soil water retention curve parameters , saturated hydraulic conductivity). Soil water retention curves parameters were measured following the evaporative method, using the Hyprop (Hydraulic Property Analyzer; UMS Munich, 2010). Parameters were assessed using Hyprop-fit software, by fitting data to Brooks and Corey and

  17. Independent steam-electric power plants in the Anthracite region, NE Pennsylvania: Site geology, coal-refuse bank utilization, and environmental benefits

    SciTech Connect

    Inners, J.D.; Edmunds, W.E.; Laregina, J.A.

    1996-12-31

    The Public Utility Regulatory Policies Act of 1978 created economic incentives that resulted in the proliferation of small independent, coal-refuse burning, steam-electric stations in Pennsylvania during the 1980`s and 1990`s. Eight such plants, ranging from 18 to 83 MW in net power output, have been operating for several years within the Anthracite region of northeastern Pennsylvania, and a ninth (having a net output of 108 MW) has recently come on line in the Lehigh Valley just to the south. All of these plants utilize circulating fluidized-bed combustion boilers in which finely crushed limestone is burned along with pulverized coal-refuse fuel. Seven are cogeneration plants that sell process steam commercially. Heat value of the pulverized coal-refuse used in the boilers ranges from 2,810 to 7,000 BTU/lb; higher values indicate washing of the fuel to remove some non-combustible material. Past episodes of bank-processing for fine coal, in addition to historic changes in coal-preparation and mining methods, give the refuse banks a complex stratigraphy in which beds vary greatly in thickness and quality. Detailed sampling and study of historic air photos are necessary to evaluate the economic potential of each individual bank. Environmental benefits of the Anthracite region`s independent power plants include: (1) removal of many black, barren piles of colliery refuse which contribute to acid-pollution and siltation of streams and (2) reclamation of strip-mined lands through disposal, compaction and grading of the alkaline ash generated by the fluidized-bed boilers.

  18. Flood variability over 1871-2012 in Northern Québec: comparison of hydrological reconstructions based on tree-rings and on geopotential height field reanalysis

    NASA Astrophysics Data System (ADS)

    Brigode, Pierre; Brissette, François; Caya, Daniel; Nicault, Antoine; Perreault, Luc; Kuentz, Anna; Mathevet, Thibault; Gailhard, Joël

    2015-04-01

    For the next couple of decades, the impacts of climate change on hydrological extremes are likely to be masked by climate natural variability. Thus, a better understanding and quantification of natural climate variability on hydrological extremes would be helpful for short-term adaptation. However, studying natural variability requires long instrumental records, which are inexistant in remote regions such as Northern Québec. Different methods have been proposed to extend observed hydroclimatic time-series, based on other data sources such as tree rings or sedimentological datasets. For example, tree ring multi-proxies have been studied for the Caniapiscau Reservoir in Northern Québec (Canada), leading to the reconstruction of spring flood series (Boucher et al., 2011) and of annual and seasonal mean flow series (Nicault et al., 2014), for the last 150 years. Here, we apply a different reconstruction method on the same catchment, using historical reanalysis of geopotential height fields, to compare the flood series obtained and study the observed flood variability over the 1871-2012 period. The applied method, named ANATEM (Kuentz et al., 2013), aims firstly at producing climatic time series (temperature and precipitation) which are then used as inputs to one or several hydrological model previously calibrated in order to obtain streamflow time series. The climatic reconstruction is based on the analog method, using the link between atmospheric pressure situations and local climatic variables and thus requires (i) a geopotential height field reanalysis (here the NOAA reanalysis, available over the 1871-2012 period (Compo et al., 2011)), and (ii) the available observed temperature and precipitation time series (here available over the 1960-2012 period). The hypothesis of the analog method is that two different days having similar atmospheric circulations are expected to produce similar temperature and precipitation patterns. Using this hypothesis, the method

  19. Streamflow variability over the 1881-2011 period in northern Québec: comparison of hydrological reconstructions based on tree rings and geopotential height field reanalysis

    NASA Astrophysics Data System (ADS)

    Brigode, Pierre; Brissette, François; Nicault, Antoine; Perreault, Luc; Kuentz, Anna; Mathevet, Thibault; Gailhard, Joël

    2016-09-01

    Over the last decades, different methods have been used by hydrologists to extend observed hydro-climatic time series, based on other data sources, such as tree rings or sedimentological datasets. For example, tree ring multi-proxies have been studied for the Caniapiscau Reservoir in northern Québec (Canada), leading to the reconstruction of flow time series for the last 150 years. In this paper, we applied a new hydro-climatic reconstruction method on the Caniapiscau Reservoir and compare the obtained streamflow time series against time series derived from dendrohydrology by other authors on the same catchment and study the natural streamflow variability over the 1881-2011 period in that region. This new reconstruction is based not on natural proxies but on a historical reanalysis of global geopotential height fields, and aims firstly to produce daily climatic time series, which are then used as inputs to a rainfall-runoff model in order to obtain daily streamflow time series. The performances of the hydro-climatic reconstruction were quantified over the observed period, and showed good performances, in terms of both monthly regimes and interannual variability. The streamflow reconstructions were then compared to two different reconstructions performed on the same catchment by using tree ring data series, one being focused on mean annual flows and the other on spring floods. In terms of mean annual flows, the interannual variability in the reconstructed flows was similar (except for the 1930-1940 decade), with noteworthy changes seen in wetter and drier years. For spring floods, the reconstructed interannual variabilities were quite similar for the 1955-2011 period, but strongly different between 1880 and 1940. The results emphasize the need to apply different reconstruction methods on the same catchments. Indeed, comparisons such as those above highlight potential differences between available reconstructions and, finally, allow a retrospective analysis of the

  20. Ambient air/near-field measurements of methane and Volatile Organic Compounds (VOCs) from a natural gas facility in Northern Europe

    NASA Astrophysics Data System (ADS)

    Baudic, Alexia; Gros, Valérie; Bonsang, Bernard; Baisnee, Dominique; Vogel, Félix; Yver Kwok, Camille; Ars, Sébastien; Finlayson, Andrew; Innocenti, Fabrizio; Robinson, Rod

    2015-04-01

    Since the 1970's, the natural gas consumption saw a rapid growth in large urban centers, thus becoming an important energy resource to meet continuous needs of factories and inhabitants. Nevertheless, it can be a substantial source of methane (CH4) and pollutants in urban areas. For instance, we have determined that about 20% of Volatile Organic Compounds (VOCs) in downtown Paris are originating from this emission source (Baudic, Gros et al., in preparation). Within the framework of the "Fugitive Methane Emissions" (FuME) project (Climate-KIC, EIT); 2-weeks gas measurements were conducted at a gas compressor station in Northern Europe. Continuous ambient air measurements of methane and VOCs concentrations were performed using a cavity ring-down spectrometer (model G2201, Picarro Inc., Santa Clara, USA) and two portable GC-FID (Chromatotec, Saint-Antoine, France), respectively. On-site near-field samplings were also carried out at the source of two pipelines using stainless steel flasks (later analyzed with a laboratory GC-FID). The objective of this study aims to use VOCs as additional tracers in order to better characterize the fugitive methane emissions in a complex environment, which can be affected by several urban sources (road-traffic, others industries, etc.). Moreover, these measurements have allowed determining the chemical composition of this specific source. Our results revealed that the variability of methane and some VOCs was (rather) well correlated, especially for alkanes (ethane, propane, etc.). An analysis of selected events with strong concentrations enhancement was performed using ambient air measurements; thus allowing the preliminary identification of different emission sources. In addition, some flasks were also sampled in Paris to determine the local natural gas composition. A comparison between both was then performed. Preliminary results from these experiments will be presented here.

  1. [Response characteristics of the field-measured spectrum for the four general types of halophyte and species recognition in the northern slope area of Tianshan Mountain in Xinjiang].

    PubMed

    Zhang, Fang; Xiong, Hei-gang; Nurbay, Abdusalih; Luan, Fu-ming

    2011-12-01

    Based on the field-measured Vis-NIR reflectance of four common types of halophyte (Achnatherum splendens(Trin.) Nevski, Sophora alopecuroides L., Camphorosma monspeliaca L. subsp. lessingii(L.)Aellen, Alhagi sparsifolia shap) within given spots in the Northern Slope Area of Tianshan Mountain in Xinjiang, the spectral response characteristics and species recognition of these types of halophyte were analyzed. The results showed that (Alhagi sparsifolia shap) had higher chlorophyll and carotenoid by CARI and SIPI index. (Sophora alopecuroides L. was at a vigorously growing state and had a higher NDVI compared with the other three types of halophyte because of its greater canopy density. But its CARI and SIPI values were lower due to the influence of its flowers. (Sophora alopecuroides L.) and (Camphorosma monspeliaca L. subsp. lessingii(L.)) had stable REPs and BEPs, but REPs and BEPs of (Achnatherum splendens(Trin.)Nevski, Aellen, Alhagi sparsifolia shap) whose spectra red shift and spectra blue shift occurred concurrently obviously changed. There was little difference in spectral curves among the four types of halophyte, so the spectrum mixing phenomenon was severe. (Camphorosma monspeliaca L. subsp. lessingii (L.)Aellen) and (Alhagi sparsifolia shap) could not be separated exactly in a usual R/NIR feature space in remote sensing. Using the stepwise discriminant analysis, five indices were selected to establish the discriminant model, and the model accuracy was discussed using the validated sample group. The total accuracy of the discriminant model was above 92% and (Achnatherum splendens(Trin.)Nevski) and (Camphorosma monspeliaca L. subsp. lessingii(L.)Aellen) could be respectively recognized 100% correctly.

  2. Mineral complexities as evidence for open-system processes in intermediate magmas of the Mount Baker volcanic field, northern Cascade arc

    NASA Astrophysics Data System (ADS)

    Escobar-Burciaga, R. D.; DeBari, S. M.

    2015-12-01

    The petrogenesis of intermediate magmas in arcs is a critical contribution to crustal growth. Andesites are commonly thought of as a hybrid product, the result of two endmember magmas mixing. At the Mount Baker volcanic field (MBVF), northern Cascade arc, andesites are the predominantly erupted lavas since 1 Ma and yet their origin is poorly constrained. Previous studies have suggested that open-system processes play a dominant role. However, the studies rely heavily on bulk rock compositions and overlook complex mineral textures and compositions. To better understand the complex processes at work at MBVF, we focus on establishing mineral and crystal clot populations in three andesitic flow units (55-59% SiO2). Petrographic and geochemical analyses suggest that variable-composition crystal clot and phenocryst populations in a single flow are related. We interpret the crystal clots to represent cumulates entrained in the erupting host magma and that related phenocrysts are disaggregates of crystal clots. The existence of common, multiple phenocryst and crystal clot populations in each flow of different age and SiO2 content provides strong evidence that intermediate magmas of MBVF are more than just the end product of mixing between two magmas. Furthermore, we suggest that most phenocrysts do not represent equilibrium products of their host liquid, evident from wide compositional ranges of ferromagnesian minerals (e.g. augite core Mg# 70-87). In fact, the most primitive phenocryst populations show the least amount of disequilibrium texture but represent assemblages expected to fractionate from basaltic to basaltic-andesitic liquids rather than equilibrium assemblages from their host bulk rock "liquid" composition. As a result, we interpret the variable SiO2 signature of the three andesitic flow units to have been obtained through the incorporation of cumulates/liquids as basaltic to basaltic-andesitic magma ascends.

  3. Streamflow variability over the 1881–2011 period in northern Quebec: comparison of hydrological reconstructions based on tree rings and geopotential height field reanalysis

    DOE PAGES

    Brigode, Pierre; Brissette, Francois; Nicault, Antoine; ...

    2016-09-06

    Over the last decades, different methods have been used by hydrologists to extend observed hydro-climatic time series, based on other data sources, such as tree rings or sedimentological datasets. For example, tree ring multi-proxies have been studied for the Caniapiscau Reservoir in northern Québec (Canada), leading to the reconstruction of flow time series for the last 150 years. In this paper, we applied a new hydro-climatic reconstruction method on the Caniapiscau Reservoir and compare the obtained streamflow time series against time series derived from dendrohydrology by other authors on the same catchment and study the natural streamflow variability over themore » 1881–2011 period in that region. This new reconstruction is based not on natural proxies but on a historical reanalysis of global geopotential height fields, and aims firstly to produce daily climatic time series, which are then used as inputs to a rainfall–runoff model in order to obtain daily streamflow time series. The performances of the hydro-climatic reconstruction were quantified over the observed period, and showed good performances, in terms of both monthly regimes and interannual variability. The streamflow reconstructions were then compared to two different reconstructions performed on the same catchment by using tree ring data series, one being focused on mean annual flows and the other on spring floods. In terms of mean annual flows, the interannual variability in the reconstructed flows was similar (except for the 1930–1940 decade), with noteworthy changes seen in wetter and drier years. For spring floods, the reconstructed interannual variabilities were quite similar for the 1955–2011 period, but strongly different between 1880 and 1940. Here, the results emphasize the need to apply different reconstruction methods on the same catchments. Indeed, comparisons such as those above highlight potential differences between available reconstructions and, finally, allow a

  4. Streamflow variability over the 1881–2011 period in northern Quebec: comparison of hydrological reconstructions based on tree rings and geopotential height field reanalysis

    SciTech Connect

    Brigode, Pierre; Brissette, Francois; Nicault, Antoine; Perreault, Luc; Kuentz, Anna; Mathevet, Thibault; Gailhard, Joel

    2016-09-06

    Over the last decades, different methods have been used by hydrologists to extend observed hydro-climatic time series, based on other data sources, such as tree rings or sedimentological datasets. For example, tree ring multi-proxies have been studied for the Caniapiscau Reservoir in northern Québec (Canada), leading to the reconstruction of flow time series for the last 150 years. In this paper, we applied a new hydro-climatic reconstruction method on the Caniapiscau Reservoir and compare the obtained streamflow time series against time series derived from dendrohydrology by other authors on the same catchment and study the natural streamflow variability over the 1881–2011 period in that region. This new reconstruction is based not on natural proxies but on a historical reanalysis of global geopotential height fields, and aims firstly to produce daily climatic time series, which are then used as inputs to a rainfall–runoff model in order to obtain daily streamflow time series. The performances of the hydro-climatic reconstruction were quantified over the observed period, and showed good performances, in terms of both monthly regimes and interannual variability. The streamflow reconstructions were then compared to two different reconstructions performed on the same catchment by using tree ring data series, one being focused on mean annual flows and the other on spring floods. In terms of mean annual flows, the interannual variability in the reconstructed flows was similar (except for the 1930–1940 decade), with noteworthy changes seen in wetter and drier years. For spring floods, the reconstructed interannual variabilities were quite similar for the 1955–2011 period, but strongly different between 1880 and 1940. Here, the results emphasize the need to apply different reconstruction methods on the same catchments. Indeed, comparisons such as those above highlight potential differences between available reconstructions and, finally, allow a retrospective

  5. Northern Nutrition.

    ERIC Educational Resources Information Center

    Northwest Territories Dept. of Education, Yellowknife.

    This guide contains nutrition information and nutrition education strategies aimed at residents of the Canadian Arctic. Section I: (1) defines nutrition terms; (2) describes the sources and functions of essential nutrients; (3) explains Canada's food guide and special considerations for the traditional northern Native diet and for lactose…

  6. Northern Nutrition.

    ERIC Educational Resources Information Center

    Northwest Territories Dept. of Education, Yellowknife.

    This guide contains nutrition information and nutrition education strategies aimed at residents of the Canadian Arctic. Section I: (1) defines nutrition terms; (2) describes the sources and functions of essential nutrients; (3) explains Canada's food guide and special considerations for the traditional northern Native diet and for lactose…

  7. Extensional Volcanism of the Taos Plateau Volcanic Field, Northern Rio Grande Rift, USA: New Insights from Geologic Mapping, 40Ar/39Ar Geochronology, Geochemistry and Geophysical Modeling

    NASA Astrophysics Data System (ADS)

    Thompson, R. A.; Turner, K. J.; Cosca, M. A.; Drenth, B.; Grauch, V. J. S.

    2016-12-01

    The Pliocene Taos Plateau Volcanic Field (TPVF) is the largest volcanic field of the Rio Grande rift. Deposits of the TPVF are distributed across 4500 km2 in the southern part of the 11,500 km2 San Luis Valley in southern Colorado and northern New Mexico constituting a major component of the structural San Luis Basin (SLB) fill. Exposed deposit thicknesses range from a few meters near the distal termini of basaltic lava flows to 240 m in the Rio Grande gorge near Taos, NM. New geologic mapping and 100 high-resolution 40Ar/39Ar age determinations help identify a complex distribution of >50 exposed eruptive centers ranging in composition from basalt to rhyolite. Total eruptive volume, estimated from geologic map relations, geophysical modeling of basin geometry and subsurface distribution of basaltic deposits, are approximately 300 km3; comprising 66% Servilleta Basalt (tholeiite), 3% mildly alkaline trachybasalt & trachyandesite, 12% olivine andesite, 17% dacite, and <1% rhyolite. Servilleta Basalt is preserved throughout the TPVF, ranging in age from 5.3 Ma to 2.95 Ma; maximum thickness is exposed in the Rio Grande gorge in association with the largest Pliocene sub-basin in the valley, the Taos graben. Smaller volume basalt centers as young as 2.9 Ma are spatially associated with monogenetic trachybasalt and trachyandesite centers ( 4.3 Ma to 2.8 Ma) along the uplifted footwall of a western fault-bounded sub-basin, the Las Mesitas graben. The plateau surface underlain primarily by Servilleta Basalt is punctuated by large ( 15 km3 erupted volume typical) monogenetic andesitic shield volcanoes ( 5-4.4 Ma); north-south aligned and distributed along the central axis of the SLB, parallel to major intrabasin faults. Large (up to 21 km3 erupted volume) zoned dacitic lava dome complexes ( 5 Ma Guadalupe Mountain/Cerro Negro, 3.9 Ma Ute Mountain, and 3 Ma San Antonio Mountain) reach elevations of 3300 m, 770 m above the valley floor each spatially and temporally associated

  8. The study of a potential CO2 repository: Integrating laboratory and field geophysical experiments to characterize the upper Muschelkalk aquifer (northern Switzerland)

    NASA Astrophysics Data System (ADS)

    Almqvist, B.; Zappone, A. S.; Misra, S.; Diamond, L.

    2011-12-01

    The upper Muschelkalk saline aquifer consists of partly dolomitized to completely dolomitized carbonate rocks of mid Triassic age (~230 Ma). This aquifer is present throughout the Swiss Molasse Basin (SMB), north of the Alps. A regional appraisal of the SMB indicates that this Formation is a potential host aquifer for sequestered CO2. However, the spatial distribution and heterogeneity of the porosity, permeability and other relevant physical and mechanical properties of the upper Muschelkalk are still poorly known. The uncertainty in this knowledge stems mainly from the weakly developed oil and gas exploration industry in Switzerland. We use an integrated approach to better constrain the aquifer physical properties, which couples field scale geophysical surveys (borehole logging and seismic reflection profiles) with laboratory analytical data. Here we focus on a set of boreholes from northern Switzerland, where geophysical data and drill core useable for laboratory measurements are available. Two sub-units comprise the upper Muschelkalk Formation. The stratigraphically higher part is a fossiliferous dolomite (>90 vol% CaMg(CO3)2; Trigodonusdolomit). The underlying unit, is composed of micritic calcite and dolomite layers interbedded with fossil-rich layers (Hauptmuschelkalk). Although both units are part of the aquifer formation, they appear to have distinctly different physical properties. The transition from Trigodonusdolomit to the Hauptmuschelkalk is marked by an increase in the sonic velocity, density and acoustic impedance. The magnitude of increase in sonic velocity can be up to 500 m/s, accompanied by an increase in acoustic impedance from 8500 to 15500 (m/s*g/cm3), but varies between the different boreholes. Poisson's ratio, determined from a single borehole, show sharp decrease at the transition. The origin of the changes in the geophysical data is likely reflecting differences in porosity and mineral composition in the Trigodonusdolomit and

  9. Dunes in Northern Summer

    NASA Image and Video Library

    2017-02-01

    This dune field formed near the base of the North Polar cap. Dunes require a source of loose particulate material to form. The source of the northern dune fields around the polar cap may be from the layers of dusty ice that are eroded by strong polar winds. This image was taken during the Martian northern summer, so there is no frost present on the dunes. The dunes closest to the base of the polar cap are long and parallel, indicating strong winds from the direction of the cap. As they get farther away from the polar cap, they start to form more crescent shaped dunes, called barchan dunes. Repeated observations by HiRISE of dunes like these show measurable changes in some locations. This discovery adds to the growing evidence that there are active processes happening all over the surface of Mars today. http://photojournal.jpl.nasa.gov/catalog/PIA11181

  10. High northern geomagnetic field behavior and new constraints on the Gilsá event: Paleomagnetic and 40Ar/39Ar results of ∼0.5-3.1 Ma basalts from Jökuldalur, Iceland

    NASA Astrophysics Data System (ADS)

    Døssing, Arne; Muxworthy, Adrian R.; Supakulopas, Radchagrit; Riishuus, Morten S.; Mac Niocaill, Conall

    2016-12-01

    Recent paleomagnetic results of extrusive rocks from high southern latitudes (>60°S) and high northern latitudes (>60°N) have been suggested to reflect a hemispheric asymmetry of the geomagnetic field on time-scales of 105 to 106 yrs, with higher and more stable fields in the north. This interpretation, however, is based on only a few modern-standard paleodirectional data sets and on high northern stable field paleointensity data of rocks that are mainly younger than 100 kyr. The sparsity of modern-standard data questions the validity (and age range) of this potential geomagnetic asymmetry. In 2013 and 2014, we sampled basaltic lava flows in Jökuldalur, north-eastern Iceland, to obtain high-standard paleodirectional and paleointensity data at relatively high-northern latitudes (65.2°N). On average, we sampled >15 cores per site at 51 sites of predominantly Matuyama age. Complete demagnetization was carried out on all samples using AF or thermal demagnetization. We present 45 distinct paleomagnetic directions based on overall N > 10 ChRMs per site and α 95 < 3.5 °. We obtain a mean direction of D = 355.7 °, I = 76.3 °, and α 95 = 3.2 for N = 45 sites that is not significantly different from a GAD field. The resulting 45 VGPs distribute around the North Pole, and the global mean paleomagnetic pole (λ bar = 87.8 °, ϕ bar = 224.3 °) is coincident with the North Pole within the α95 confidence limit. We calculate a VGP dispersion S B (Mat) = 20.523.3/17.8 and an average inclination anomaly ΔI = - 0.91 ° 2.94/-4.88 for our 38 Matuyama age data. The dispersion SB overall supports the interpretation of a dependence of SB on latitude during the Matuyama, while the negligible ΔI suggests little deviation from a GAD field. Based on relatively strict cut-off criteria we also present six new field strength estimates from the time interval ∼1.2-1.83 Ma, thus filling a large data gap of the high-northern stable field behavior. We obtain a median VADM of 57 ± 3

  11. Regional-scale geometry of the central Skellefte district, northern Sweden—results from 2.5D potential field modeling along three previously acquired seismic profiles

    NASA Astrophysics Data System (ADS)

    Tavakoli, Saman; Bauer, Tobias E.; Elming, Sten-Åke; Thunehed, Hans; Weihed, Pär

    2012-10-01

    The Skellefte district in northern Sweden is one of the most important mining districts in Europe hosting approximately 80 volcanic massive sulfide (VMS) deposits. Due to its economical importance, geological and geophysical studies were carried out in order to create an image of the geometry of the upper crustal structure and integral geological elements and to evaluate their relationship to mineral deposits. Consequently, seismic reflection data along three sub-parallel profiles were acquired during 2009-2010 to map the spatial relationships between the geological structures down to a depth of ~ 4.5 km. Although these seismic studies helped researchers understand the regional relationship between geologic units in the central Skellefte district (CSD), the seismic reflection data did not succeed entirely in mapping the lithological contacts in the area. In this study, the model derived from the seismic reflection data was examined by using 2.5D modeling of potential field data (down to a 5 km depth) constrained by physical properties of the rocks and surface geology. Moreover, we modeled gravity and magnetic data along the non-reflective or poorly reflective parts of the seismic profiles to identify major lithological contacts and shear zones in the CSD, which could not be modeled on the basis of the seismic reflection data. Gravity and magnetic data helped reveal the spatial relationship between the Skellefte volcanic rocks, Vargfors group meta-sedimentary rocks and two meta­intrusive complexes. Results suggest a maximum depth extent of 2.1 km for the tectonic contact at the southern border of the Jörn granitoid. Furthermore, this north-dipping Skellefte-Jörn contact coincides closely with magnetic lows and gravity highs, which implies that the Jörn intrusive rocks have a greater thickness than the underlying basalt. Further to the NW, gravity and magnetic data suggest a depth extent of 2 km for the Gallejaur complex, which coincides with a set of gently

  12. Constraints on the seismic properties of the mantle beneath the Nógrád-Gömör Volcanic Field (Northern Pannonian Basin)

    NASA Astrophysics Data System (ADS)

    Klebesz, Rita; Liptai, Nora; Kovacs, Istvan; Patko, Levente; Pinter, Zsanett; Falus, Gyorgy; Graczer, Zoltan; Szanyi, Gyongyver; Wesztergom, Viktor; Szabo, Csaba

    2014-05-01

    In the Carpathian Pannonian Region (CPR) Plio-Pleistocene alkali basalts have sampled the upper mantle at five known occurrences, bringing upper mantle xenoliths to the surface. One of these is the Nógrád-Gömör Volcanic Field (NGVF), which is located in the northern part of the Pannonian Basin. For this study, 25 representative lherzolite and wehrlite xenoliths were selected from the central and southern parts of the NGVF. These xenoliths sample a small volume (~4000 km3) of the upper mantle from a depth of about 35-50 km. Xenoliths collected from the southern part of NGVF originate from shallower depth (35-40 km) than those from the central part (40-50 km) [1]. Crystal preferred orientations (CPO) of the minerals were measured by electron backscatter diffraction (EBSD). Two distinct orientation types (A-Type, D-Type) based on the distribution and alignment of crystallographic axes were recognized, which show some correlation not only with the macroscopic texture, but also with olivine J-factors that indicate the strength of the xenolith fabric [2]. The seismic properties, i.e. seismic anisotropy and velocities, of these 25 mantle xenoliths were calculated based on the CPO and volume fractions of olivine, ortho- and clinopyroxene. It was found that P wave and fast split shear wave polarization direction is always close to the density maximum of the a-axis of olivine. Seismic anisotropy is higher for stronger CPO. Maximum P wave azimuthal anisotropy ranges are 4.5%-6.9% and 5.3%-11.9%, for the southern and the central area respectively. Maximum S wave polarization anisotropy ranges are 2.92%-5.31% and 3.97%-7.46%for the southern area and the central area respectively. The anisotropy that would be measured by SKS, Rayleigh and Love waves for end-member orientations of the lineation and foliation could be predicted based on the already calculated seismic properties of the xenoliths [3]. The calculated anisotropy is compared to the results of S receiver function

  13. Results from expert tests of the TP-100A boiler at the Lugansk thermal power station during the combustion of lean coal and anthracite culm with addition of RA-GEN-F anaklarid

    NASA Astrophysics Data System (ADS)

    Mikhailov, V. E.; Tupitsyn, S. P.; Sokolov, V. V.; Chebakova, G. F.; Malygin, V. I.; Yazykov, Yu. V.; Kharchenko, A. V.; Chetverikov, A. N.

    2012-08-01

    Results from expert tests of separated combustion of Grade T and Grade ASh anthracite culm in the TP-100A boiler No. 15 at the Lugansk thermal power station carried out with and without addition of RA-GEN-F anaklarid are presented. The possibility of extending the boiler load adjustment range and excluding the use of natural gas for supporting the flame at minimal loads is considered.

  14. Initial results from the Volcanic Risk in Saudi Arabia project: Microearthquakes in the northern Harrat Rahat monogenetic volcanic field, Madinah, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Kenedi, C. L.; Alvarez, M. G.; Abdelwahed, M. F.; Aboud, E.; Lindsay, J. M.; Mokhtar, T. A.; Moufti, M. R.

    2012-12-01

    An 8-station borehole seismic research array is recording microearthquake data in northern Harrat Rahat. This recently active monogenetic volcanic field lies southeast of the Islamic holy city of Madinah, Kingdom of Saudi Arabia. The VORiSA seismographs are operated in collaboration between King Abdulaziz University in Jeddah and the Institute of Earth Science and Engineering, University of Auckland, in New Zealand. The goal of the VORiSA project is to evaluate the seismic and volcanic hazard around Madinah. To this end, we will evaluate the local earthquake activity including the extent to which local earthquakes are tectonic or volcanic. We also will use seismicity to understand the subsurface structure. The analytical goals of the seismic research array are the following: (1) Calculate a new seismic velocity model, (2) Map subsurface structures using seismic tomography, and (3) Explore for fracture zones using shear wave splitting analysis. As compared to seismographs installed on the surface, borehole seismometers detect smaller and more numerous microearthquake signals. The sensitivity and location of the borehole sensors in the VORiSA array are designed to detect these weak signals. The array has a total aperture of 17 km with station spacing at 5 - 10 km. The seismometers are housed in IESE model S21g-2.0, two Hz, 3-component borehole sondes. Sensor depths range from 107 - 121 m. The data acquisition system at each stand-alone station consists of a Reftek 130-01, 6-channel, 24 bit data logger which records at 250 samples per second. The power source is a deep cycle battery with solar recharge. Local temperatures reach extremes of 0° to 50°C, so the battery and recorder are contained in a specially designed underground vault. The vault also provides security in the remote and sparsely populated volcanic field. Recording began on 31 March 2012. An average of one earthquake every three days suggests that currently this is not a highly seismic area. However

  15. Northern Pintail (Anas acuta)

    USGS Publications Warehouse

    Austin, J.E.; Miller, M.R.; Poole, A.; Gill, F.

    1995-01-01

    The Northern Pintail is a medium-sized dabbling duck of slender, elegant lines and conservative plumage coloration. It is circumpolar in distribution and abundant in North America, with core nesting habitat in Alaska and the Prairie Pothole Region of southern Canada and the northern Great Plains. Breeders favor shallow wetlands interspersed throughout prairie grasslands or arctic tundra. An early fall migrant, the species arrives on wintering areas beginning in August, after wing molt, often forming large roosting and feeding flocks on open, shallow wetlands and flooded agricultural fields. The birds consume grains, marsh plant seeds, and aquatic invertebrates throughout the fall and winter. Northern Pintails are among the earliest nesting ducks in North America, beginning shortly after ice-out in many northern areas. Individuals form new pair bonds each winter but are highly promiscuous during the nesting season, with mated and unmated males often involved in vigorous, acrobatic Pursuit Flights. Annual nest success and productivity vary with water conditions, predation, and weather. Females build nests on the ground, often long distances from water. Only the female incubates; her mate leaves shortly after incubation begins. Ducklings hatch together in one day, follow the female to water after a day in the nest, and fledge by July or August. Adults and ducklings consume mainly aquatic invertebrates during the breeding season. Predators and farming operations destroy many thousands of Northern Pintail nests annually; farming has also greatly reduced the amount of quality nesting cover available. Winter habitats are threatened by water shortages, agricultural development, contamination, and urbanization. Periods of extended drought in prairie nesting regions have caused dramatic population declines, usually followed by periods of recovery. Over the long term, however, the continental population of Northern Pintails has declined significantly from 6 million birds in

  16. Identification of new NE-trending deep-seated faults and tectonic pattern updating in northern Tunisia (Mogodos-Bizerte region), insights from field and seismic reflection data

    NASA Astrophysics Data System (ADS)

    Essid, El Mabrouk; Kadri, Ali; Inoubli, Mohamed Hedi; Zargouni, Fouad

    2016-07-01

    The northern Tunisia is occupied by the Tellian domain constituent the eastern end of the Maghrebides, Alpine fold-thrust belt. Study area includes partially the Tellian domain (Mogodos belt) and its foreland (Bizerte region). Most of this region outcrops consist of Numidian thrust sheet flysch attributed to the lower Oligocene-Burdigalian. In the study area, the major fault systems are still subject of discussion. The Numidian nappe structure, the distribution of basalt and Triassic outcrops within and at the front of this Tellian domain deserve more explanation. In this work we intend to update the structural scheme and the tectonic evolution of the northern Tunisia, taking into account salt tectonics and magmatism. The updated tectonic evolution will be integrated in the geodynamic framework of the Central Mediterranean. For this purpose, we have analyzed morphologic, seismic and structural data. The compilation of the results has allowed the identification of new regional NE-trending faults dipping towards the NW: the Bled el Aouana-Bizerte, the Sejnane-Ras Enjla and the Oued el Harka faults. They correspond to the reactivation of deep-seated normal faults splaying on the Triassic evaporites. This fault system constitutes the main component of the northern Tunisia structural scheme and has influenced its tectonic evolution marked by the main following stages. The Tellian thrust-sheets were immobilized at the uppermost Langhian. During the major Tortonian NW-trending compressive phase, these faults were reactivated with reverse kinematics and controlled the distribution of the post-nappes Neogene continental deposits. At the early Pleistocene, a compressive NNW-trending event has reactivated again these faults with sinistral-reverse movements and deformed the post-nappes Neogene series. Late Quaternary to Actual, the tectonic regime continues to be compressive with a NNW-trending maximum horizontal stress.

  17. Vertical Distribution and Columnar Optical Properties of Springtime Biomass-Burning Aerosols over Northern Indochina during the 7-SEAS/BASELInE field campaign

    NASA Astrophysics Data System (ADS)

    Lin, N. H.; Wang, S. H.; Welton, E. J.; Holben, B. N.; Tsay, S. C.; Giles, D. M.; Stewart, S. A.; Janjai, S.; Anh, N. X.; Hsiao, T. C.; Chen, W. N.; Lin, T. H.; Buntoung, S.; Chantara, S.; Wiriya, W.

    2015-12-01

    In this study, the aerosol optical properties and vertical distributions in major biomass-burning emission area of northern Indochina were investigated using ground-based remote sensing (i.e., four Sun-sky radiometers and one lidar) during the Seven South East Asian Studies/Biomass-burning Aerosols & Stratocumulus Environment: Lifecycles & Interactions Experiment conducted during spring 2014. Despite the high spatial variability of the aerosol optical depth (AOD; which at 500 nm ranged from 0.75 to 1.37 depending on the site), the temporal variation of the daily AOD demonstrated a consistent pattern among the observed sites, suggesting the presence of widespread smoke haze over the region. Smoke particles were characterized as small (Ångström exponent at 440-870 nm of 1.72 and fine mode fraction of 0.96), strongly absorbing (single-scattering albedo at 440 nm of 0.88), mixture of black and brown carbon particles (absorption Ångström exponent at 440-870 nm of 1.5) suspended within the planetary boundary layer (PBL). Smoke plumes driven by the PBL dynamics in the mountainous region reached as high as 5 km above sea level; these plumes subsequently spread out by westerly winds over northern Vietnam, southern China, and the neighboring South China Sea. Moreover, the analysis of diurnal variability of aerosol loading and optical properties as well as vertical profile in relation to PBL development, fire intensity, and aerosol mixing showed that various sites exhibited different variability based on meteorological conditions, fuel type, site elevation, and proximity to biomass-burning sources. These local factors influence the aerosol characteristics in the region and distinguish northern Indochina smoke from other biomass-burning regions in the world.

  18. Structure and evolution of the northern Barents-Kara Sea continental margin from integrated analysis of potential fields, bathymetry and sparse seismic data

    NASA Astrophysics Data System (ADS)

    Minakov, A.; Faleide, J. I.; Glebovsky, V. Yu.; Mjelde, R.

    2012-01-01

    The northern Barents-Kara Sea continental margin is a poorly investigated area because of a permanent ice cover hampering seismic exploration. The available geological and geophysical data show that the magma-poor margin developed in response to early Cenozoic break-up and subsequent opening of the Arctic Eurasia Basin. In this study, a series of crustal-scale geotransects illustrating the architecture of the continental margin are constructed using sparse seismic reflection profiles and a gravity inversion method incorporating a thermal model of rifting. The continental side of the northern Barents Sea margin is underlain by Palaeozoic-Early Mesozoic deep sedimentary basins separated from the oceanic side by the marginal uplift. A bathymetry analysis complements low-resolution seismic data to predict the sedimentary depocenters beyond the shelf break. These depocenters are associated with troughs, perpendicular to the shelf edge. The depocenter in front of the St. Anna Trough may contain a sedimentary section more than 4 km thick. The gravity correction for the effect of sedimentary cover was added to the inversion. This correction used an exponential density-depth function. The inversion supports a narrow and steep continent-ocean transition (COT; ca. 100 km). The conjugate Lomonosov Ridge margin is modelled using the same technique. Palaeoreconstructions were made to predict the break-up setting. The northern Barents Sea-Lomonosov Ridge rift system can be described as an initially narrow symmetric rift. A transitional zone of extreme thinning is assumed between the oldest spreading magnetic anomaly and the stretched continental crust. The free-air gravity anomaly in the western part of the margin can be predicted by the upwelling divergent flow model implying the exhumation of the lower crust and the continental upper mantle within the COT. It is suggested that an episode of shear or oblique extension before breakup is required to explain the observed narrow

  19. The doubly vergent inverted structures in the Mesozoic basins of northern Chile (28°S): A comparative analysis from field data and analogue modeling

    NASA Astrophysics Data System (ADS)

    Martínez, Fernando; Cristallini, Ernesto

    2017-08-01

    Doubly vergent contractional structures are common features in many regions of the Central Andes. They represent the first-order structural style observed in the inverted Mesozoic basins located along the flat-slab subduction segment of northern Chile. Here, we present a comparative analyses based on geological data previously published and a series of analogue models that were applied to understand the geometry and kinematics of doubly vergent structures related to tectonic inversion, similar to those exposed along the Chanarcillo and Lautaro basins located in northern Chile at 28°S. Our experiments consisted of orthogonal shortening of sand-microbead mixture models located over two pre-existing antithetic master normal faults separated by a structural high to reproduce their tectonic inversion. During the tests, we evaluated the influence of the distance between the master normal faults and synorogenic sedimentation on the final configuration of the doubly vergent structures. The results showed that: a) the tectonic inversion of antithetic normal faults separated by structural highs geometrically reproduce the doubly vergent structures confined to the edge of the Chañarcillo and Lautaro basins. This pre-shortening initial configuration is required to create doubly vergent systems composed of opposite-dipping inverted faults; b) the initial separation distance between the antithetic normal faults strongly influenced the final configuration of the doubly vergent structures during their tectonic inversion. Narrow separations can produce more complex tectonic scenarios; c) the synorogenic sedimentation between the inverted faults can modify the final geometry of the doubly vergent inverted structures, since it allows the shortening to be preferentially accumulated by inversion anticlines. Finally we conclude that although these results can be comparable with the main structures present in the Mesozoic inverted basins of northern Chile, some geological features

  20. Field experiments on the behaviour of malaria vectors in an unsprayed hut and in a hut sprayed with DDT in Northern Nigeria

    PubMed Central

    Kuhlow, F.

    1962-01-01

    Investigations on the behaviour of malaria vectors in DDT-sprayed houses are of special interest in malaria control campaigns. In the Northern Region of Nigeria the behaviour of the local vectors was studied by means of experimental huts fitted with exit window-traps. The results obtained show a marked reduction in the number of mosquitos entering the sprayed hut and a depression of the biting rate. The most striking observation is the large number of A. gambiae and of A. funestus that left the sprayed hut and the considerable proportion that escaped unharmed. Both figures show a very marked increase in subsequent months after spraying, indicating a rapid loss of the lethal action of the DDT residue along with a long-lasting irritant effect. It is concluded that under the particular local conditions the application of 1.9 g/m2 DDT twice a year may not be sufficient to interrupt malaria transmission in the Northern Region of Nigeria. PMID:14460322

  1. Time-temperature-burial significance of Devonian anthracite implies former great (approx. 6. 5 km) depth of burial of Catskill Mountains, New York

    SciTech Connect

    Friedman, G.M.; Sanders, J.E.

    1982-02-01

    Specimens of coalified plant debris in Tully-correlative strata of the Gilboa Formation (uppermost Middle Devonian) within the eastern Catskill Mountains of New York State have been converted to anthracite having a vitrinite reflectance of 2.5%. This implies a level of organic metamorphism (LOM) of 16. The specimens are about 350 m.y. old; if 200 m.y. is taken as the duration of the time of exposure to the maximum geothermal temperature, then the LOM of 16 and other thermal indicators imply a maximum temperature of 190/sup 0/C. Using a geothermal gradient of 26/sup 0/C.km/sup -1/ (17/sup 0/F.1,000 ft/sup -1/), a former depth of burial of 6.5 km is implied. Such former deep burial is not usually inferred for the Catskills, but it is consistent with the idea that the thick (about 6.4 km or 21,000 ft) Carboniferous strata of northeastern Pennsylvania formerly extended northeast far enough to bury the Catskills. The lack of metamorphism of the Paleozoic strata lying about 4.5 km beneath the Tully-correlative rocks and exposed in the adjacent Hudson Valley places low limits on the former geothermal gradient; this supports the concept of great depth of former burial of the Catskills. For example, 6.5 km of former burial and a geothermal gradient of 26/sup 0/C.km/sup -1/ imply a temperature of 307/sup 0/C for the base of the Paleozoic. By contrast, only 1 km of former burial requires a geothermal gradient of 170/sup 0/C.km/sup -1/, which would have subjected the base of the Paleozoic to a temperature of 955/sup 0/GAMMA, which is far higher than the 600 to 650/sup 0/C recently inferred for the Acadian-age metamorphism of the Taconic allochthon in southwestern Massachusetts and adjoining areas.

  2. Relationship between textural properties, fly ash carbons, and Hg capture in fly ashes derived from the combustion of anthracitic pulverized feed blends

    SciTech Connect

    Isabel Surez-Ruiz; Jose B. Parra

    2007-08-15

    In this work, the textural properties of a series of whole anthracitic-derived fly ashes sampled in eight hoppers from the electrostatic precipitators and their sized fractions (from {gt}150 to {lt}25 {mu}m) are investigated. Data from N{sub 2} adsorption isotherms at 77 K, helium density, and mercury porosimetry have contributed to establish a relationship between the Brunauer-Emmett-Teller (BET) surface areas, VTOT, porosity, carbon content (the type of fly ash carbons), and Hg retention in these fly ashes. The unburned carbons in these ashes are macroporous materials, and they are different from the carbons in fly ashes from classes C and F (the latter derived from the combustion of bituminous coals) and show different textural properties. These ashes represent the end member of the fly ash classes C and F with respect to certain textural properties. Although the BET surface area and VTOT values for the studied samples are the lowest reported, they increase with the increase in carbon content, anisotropic carbon content, and particle size of the ashes. Thus, a positive relationship between all these parameters and Hg capture by the coarser ash fractions was found. The finest fraction of carbons ({lt}25 {mu}m) represented an exception. Although it makes a significant contribution to the total carbon of the whole fly ashes and shows relatively higher surface areas and VTOT values, its Hg concentration was found to be the lowest. This suggests that the type of unburned carbons in the finest fraction and/or other adsorption mechanisms may play a role in Hg concentration. Because the textural properties of anisotropic carbons depend on their subtype and on their origin, the need for its differentiation has been evidenced. 54 refs., 8 figs., 3 tabs.

  3. Lithospheric structure and geodynamic evolution of the northern Molucca Sea area constrained by 3-D gravity field inversion of a combined sea-surface and satellite gravity dataset

    NASA Astrophysics Data System (ADS)

    Widiwijayanti, C.; Tiberi, C.; Diament, M.; Deplus, C.; Mikhailov, V.; Louat, R.; Tikhotsky, S.; Gvishiani, A.

    2003-04-01

    The Molucca Sea extending from northeastern Indonesia to southern Philippines islands, is a zone of oceanic basin closure between two opposite-facing subduction zones. This convergence results in the collision of two subduction zones, which style evolves from the southern to the northern parts of the Molucca Sea. In order to provide new insights into the present-day lithospheric structures in the Molucca Sea area, we inverted satellite and sea-surface gravity data into an iterative scheme including a priori seismological data. The seismological data were collected from two networks of Ocean Bottom Seismometer (OBS). These data allowed us to locate local seismic events and to build 3D tomographic images. We relate these results to the different stages of collision. The gravity data consists of combined sea-surface and satellite derived gravity. We used Kolmogorov-Wiener optimal (mean-square) filter to extract the gravity signal associated with lithospheric structures, then analyzed it to determine main regional features of lithospheric structure. For this purpose we employed a selection of Euler solutions based on a new clustering technique. To identify the geometry and nature of lithospheric structures, we also performed a 3-D gravity inversion for the northern Molucca Sea data, introducing our tomographic model as an independent constraint. The combination of both methods permits us to obtain a coherent image of the lithospheric structure. The results of this study illustrate the heterogeneity of lithospheric units in the northern Molucca Sea, which results from the collision between the Sangihe margin and lithospheric fragments from the Phillipine plate such as the Snellius plateau or the Halmahera volcanic arc. Three phenomena can explain the observed lithospheric structure: 1) the rupture of the Molucca Sea plate, accompanied by the appearance at the surface of slices of oceanic crust, favoring the development of suture zones as the collision evolves, 2) the

  4. Lateral extrusion of the northern Tibetan Plateau interpreted from seismic images, potential field data, and structural analysis of the eastern Kunlun fault

    NASA Astrophysics Data System (ADS)

    Xu, Xiao; Gao, Rui; Dong, Shuwen; Wang, Haiyan; Guo, Xiaoyu

    2017-01-01

    The extrusion model suggests that the India-Eurasia collision triggered lateral escape of the Tibetan Plateau via strike-slip faults from south to north. However, questions remain as to how the collision resulted in the different geological settings of northern Tibet. The area between the Haiyuan fault and the eastern Kunlun fault is ideal for investigating whether major strike-slip faults contributed to lateral extrusion of the plateau. This study uses a deep seismic profile spanning a 257 km transect, along with regional geologic, gravity, and magnetic data. Examining our results integrated with those of previous studies, we propose that the block between the Elashan and Riyueshan faults extruded southward under the background of a large-scale eastward extrusion of the Tibetan Plateau. According to regional tectonic events, the north-dipping intracrustal seismic reflectors that appear beneath the Western Qinling orogen are the remnants of the Indosinian Mianlue suture zone. The subduction of the Mianlue Ocean led to the underthrusting of South China beneath the Qinling orogen, similar to the process that occurred in the Western Kunlun Range and central Alps. As a result, the Moho was duplicated beneath the Western Qinling orogen. Southward extrusion resulted in the offset of the eastern Kunlun fault from the Diebu-Bailongjiang fault, which transferred part of the Western Qinling orogen to the Ruo'ergai basin and pulled the Ruo'ergai basin as well. Based on interpretations of structures and other evident features, we develop a kinematic model to specifically explain how the northern Tibetan Plateau between the Elashan and Riyueshan faults, located between the Haiyuan and Kunlun faults, accommodates southwesterly compression.

  5. Palynological evidence of the replacement of the hygrophilous forest by field vegetation during the last 7,000 years B.P. in the northern coast of Rio de Janeiro, Brazil.

    PubMed

    Luz, Cynthia F P da; Barth, Ortrud M; Martin, Louis; Silva, Cleverson G; Turcq, Bruno J

    2011-09-01

    Historians claim that European colonizers of the northern coast of Rio de Janeiro State found vast herbaceous fields when arrived in this region. Hypotheses about the origin of these fields include forest burning by the Goitacás indians and periodical floods by the Paraíba do Sul River and the lagoon system. The palynologycal analysis of two lake cores obtained in the municipality of Campos dos Goytacazes revealed opening episodes of hygrophilous forest and the establishment of field vegetation, recorded at ca. 6,500 and ca. 4,000 (14)C yr BP. The partial replacement of forest by field vegetation in the first episode was probably caused by floods of the lower areas during the development of the Holocene lagoon phase. During the second episode, successions of vegetational patterns occurred due to lowering of the sea level. Drying and enlarging of the coastal plain have allowed its colonization by herbs and heliophyte plants. The palynological analysis does not provide any evidence that sustains the theories of use of fire and agricultural activities by indigenous groups during these periods.

  6. Geology and geochemistry of volcanic centers within the eastern half of the Sonoma volcanic field, northern San Francisco Bay region, California

    USGS Publications Warehouse

    Sweetkind, Donald S.; Rytuba, James J.; Langenheim, V.E.; Fleck, Robert J.

    2011-01-01

    The volcanic fields in the California Coast Ranges north of San Francisco Bay are temporally and spatially associated with the northward migration of the Mendocino triple junction and the transition from subduction and associated arc volcanism to a slab window tectonic environment. Our geochemical analyses from the Sonoma volcanic field highlight the geochemical diversity of these volcanic rocks, allowing us to clearly distinguish these volcanic rocks from those of the roughly coeval ancestral Cascades magmatic arc to the west, and also to compare rocks of the Sonoma volcanic field to rocks from other slab window settings.

  7. Time-temperature-burial significance of Devonian anthracite implies former great (˜6.5 km) depth of burial of Catskill Mountains, New York

    NASA Astrophysics Data System (ADS)

    Friedman, Gerald M.; Sanders, John E.

    1982-02-01

    Specimens of coalified plant debris in Tully-correlative strata of the Gilboa Formation (uppermost Middle Devonian) within the eastern Cat-skill Mountains of New York State have been converted to anthracite having a vitrinite reflectance of 2.5%. This implies a level of organic metamorphism (LOM) of 16. A similar degree of thermal activity is implied by the black color (Staplin kerogen-alteration index of 4) of the associated (possibly recycled) carbonized kerogen, a conodont-alteration index of 4, and authigenic chlorite and local sericite fillings of the former interparticle pores of interbedded sandstones. The specimens are about 350 m.y. old; if 200 m.y. is taken as the duration of the time of exposure to the maximum geothermal temperature, then the LOM of 16 and other thermal indicators imply a maximum temperature of 190 °C. Using a geothermal gradient of 26 °C · km-1 (17 °F · 1,000 ft-1), a former depth of burial of 6.5 km is implied. Such former deep burial is not usually inferred for the Catskills, but it is consistent with the idea that the thick (about 6.4 km or 21,000 ft) Carboniferous strata of northeastern Pennsylvania formerly extended northeast far enough to bury the Catskills. The lack of metamorphism of the Paleozoic strata lying about 4.5 km beneath the Tully-correlative rocks and exposed in the adjacent Hudson Valley places low limits on the former geothermal gradient; this supports the concept of great depth of former burial of the Catskills. For example, 6.5 km of former burial and a geothermal gradient of 26 °C · km-1 imply a temperature of 307 °C for the base of the Paleozoic. By contrast, only 1 km of former burial requires a geothermal gradient of 170 °C · km-1, which would have subjected the base of the Paleozoic to a temperature of 955 °C, which is far higher than the 600 to 650 °C recently inferred for the Acadian-age metamorphism of the Taconic allochthon in southwestern Massachusetts and adjoining areas.

  8. Abandoned mine drainage in the Swatara Creek Basin, southern anthracite coalfield, Pennsylvania, USA: 1. stream quality trends coinciding with the return of fish

    USGS Publications Warehouse

    Cravotta, Charles A.; Brightbill, Robin A.; Langland, Michael J.

    2010-01-01

    Acidic mine drainage (AMD) from legacy anthracite mines has contaminated Swatara Creek in eastern Pennsylvania. Intermittently collected base-flow data for 1959–1986 indicate that fish were absent immediately downstream from the mined area where pH ranged from 3.5 to 7.2 and concentrations of sulfate, dissolved iron, and dissolved aluminum were as high as 250, 2.0, and 4.7 mg/L, respectively. However, in the 1990s, fish returned to upper Swatara Creek, coinciding with the implementation of AMD treatment (limestone drains, limestone diversion wells, limestone sand, constructed wetlands) in the watershed. During 1996–2006, as many as 25 species of fish were identified in the reach downstream from the mined area, with base-flow pH from 5.8 to 7.6 and concentrations of sulfate, dissolved iron, and dissolved aluminum as high as 120, 1.2, and 0.43 mg/L, respectively. Several of the fish taxa are intolerant of pollution and low pH, such as river chub (Nocomis icropogon) and longnose dace (Rhinichthys cataractae). Cold-water species such as brook trout (Salvelinus fontinalis) and warm-water species such as rock bass (Ambloplites rupestris) varied in predominance depending on stream flow and stream temperature. Storm flow data for 1996–2007 indicated pH, alkalinity, and sulfate concentrations decreased as the stream flow and associated storm-runoff component increased, whereas iron and other metal concentrations were poorly correlated with stream flow because of hysteresis effects (greater metal concentrations during rising stage than falling stage). Prior to 1999, pH\\5.0 was recorded during several storm events; however, since the implementation of AMD treatments, pH has been maintained near neutral. Flow-adjusted trends for1997–2006 indicated significant increases in calcium; decreases in hydrogen ion, dissolved aluminum, dissolved and total manganese, and total iron; and no change in sulfate or dissolved iron in Swatara Creek immediately downstream from the

  9. Field-based evaluation of two herbaceous plant community composition sampling methods for long-term monitoring in Northern Great Plains National Parks

    USGS Publications Warehouse

    Symstad, Amy J.; Wienk, Cody L.; Thorstenson, Andy

    2006-01-01

    The Northern Great Plains Inventory & Monitoring (I&M) Network (Network) of the National Park Service (NPS) consists of 13 NPS units in North Dakota, South Dakota, Nebraska, and eastern Wyoming. The Network is in the planning phase of a long-term program to monitor the health of park ecosystems. Plant community composition is one of the 'Vital Signs,' or indicators, that will be monitored as part of this program for three main reasons. First, plant community composition is information-rich; a single sampling protocol can provide information on the diversity of native and non-native species, the abundance of individual dominant species, and the abundance of groups of plants. Second, plant community composition is of specific management concern. The abundance and diversity of exotic plants, both absolute and relative to native species, is one of the greatest management concerns in almost all Network parks (Symstad 2004). Finally, plant community composition reflects the effects of a variety of current or anticipated stressors on ecosystem health in the Network parks including invasive exotic plants, large ungulate grazing, lack of fire in a fire-adapted system, chemical exotic plant control, nitrogen deposition, increased atmospheric carbon dioxide concentrations, and climate change. Before the Network begins its Vital Signs monitoring, a detailed plan describing specific protocols used for each of the Vital Signs must go through rigorous development and review. The pilot study on which we report here is one of the components of this protocol development. The goal of the work we report on here was to determine a specific method to use for monitoring plant community composition of the herb layer (< 2 m tall).

  10. Field-Based Evaluation of Two Herbaceous Plant Community Composition Sampling Methods for Long-Term Monitoring in Northern Great Plains National Parks

    USGS Publications Warehouse

    Symstad, Amy J.; Wienk, Cody L.; Thorstenson, Andy

    2006-01-01

    The Northern Great Plains Inventory & Monitoring (I&M) Network (Network) of the National Park Service (NPS) consists of 13 NPS units in North Dakota, South Dakota, Nebraska, and eastern Wyoming. The Network is in the planning phase of a long-term program to monitor the health of park ecosystems. Plant community composition is one of the 'Vital Signs,' or indicators, that will be monitored as part of this program for three main reasons. First, plant community composition is information-rich; a single sampling protocol can provide information on the diversity of native and non-native species, the abundance of individual dominant species, and the abundance of groups of plants. Second, plant community composition is of specific management concern. The abundance and diversity of exotic plants, both absolute and relative to native species, is one of the greatest management concerns in almost all Network parks (Symstad 2004). Finally, plant community composition reflects the effects of a variety of current or anticipated stressors on ecosystem health in the Network parks including invasive exotic plants, large ungulate grazing, lack of fire in a fire-adapted system, chemical exotic plant control, nitrogen deposition, increased atmospheric carbon dioxide concentrations, and climate change. Before the Network begins its Vital Signs monitoring, a detailed plan describing specific protocols used for each of the Vital Signs must go through rigorous development and review. The pilot study on which we report here is one of the components of this protocol development. The goal of the work we report on here was to determine a specific method to use for monitoring plant community composition of the herb layer (< 2 m tall).

  11. Assessing five field sampling methods to monitor Yellowstone National Park's northern ungulate winter range: the advantages and disadvantages of implementing a new sampling protocol

    Treesearch

    Pamela G. Sikkink; Roy Renkin; Geneva Chong; Art Sikkink

    2013-01-01

    The five field sampling methods tested for this study differed in richness and Simpson's Index values calculated from the raw data. How much the methods differed, and which ones were most similar to each other, depended on which diversity measure and which type of data were used for comparisons. When the number of species (richness) was used as a measure of...

  12. Carbon sequestration in croplands is mainly driven by management leading to increased net primary production - evidence from long-term field experiments in Northern Europe

    NASA Astrophysics Data System (ADS)

    Kätterer, Thomas; Bolinder, Martin Anders; Börjesson, Gunnar; Kirchmann, Holger; Poeplau, Christopher

    2014-05-01

    Sustainable intensification of agriculture in regions with high production potential is a prerequisite for providing services for an increasing human population, not only food, animal feed, fiber and biofuel but also to promote biodiversity and the beauty of landscapes. We investigated the effect of different management practices on soil fertility and carbon sequestration in long-term experiments, mainly from Northern Europe. In addition, a meta-analysis on the effect of catch crops was conducted. Improved management of croplands was found to be a win-win strategy resulting in both increased soil fertility and carbon sequestration. We quantified the effect of different management practices such as N fertilization, organic amendments, catch crops and ley-arable rotations versus continuous annual cropping systems on soil carbon stocks. Increasing net primary productivity (NPP) was found to be the main driver for higher soil carbon storage. Mineral N fertilization increased soil carbon stocks by 1-2 kg C ha-1 for each kg of N applied to cropland. Ley-arable rotations, being a combination of annual and perennial crops, are expected to have C stocks intermediate between those of continuous grass- and croplands. A summary of data from 15 long-term sites showed that on average 0.5 Mg ha-1 yr-1 (range 0.3 to 1.1; median 0.4 Mg ha-1 yr-1) more carbon was retained in soils in ley-arable compared to exclusively annual systems, depending on species composition, management, soil depth and the duration of the studies. The annual C accumulation rate for catch crops determined in the meta-analysis was well within that range (0.32±0.08 Mg C ha-1 yr-1). Retention factors calculated for straw, manure, sawdust, peat, sewage sludge and composted household waste varied widely in a decadal time scale. Retention of root and rhizodeposit carbon was higher than for above-ground crop residues. We conclude that NPP is the major driver for C sequestration and emphasize that increased soil

  13. Confederate King of Battle: A Comparison of the Field Artillery Corps of the Army of Northern Virginia and the Army of Tennessee

    DTIC Science & Technology

    2008-12-12

    attention. One recent and notable book on the subject is Cannoneers in Gray by Larry J. Daniel. However, unlike Two Great Rebel Armies, there has been... copper . The strategically important Virginia and Tennessee Railroad also ran through the area. Therefore, troops were continually siphoned off to...McMurry, 80. 8 Larry Daniel, Cannoneers in Gray : The Field Artillery of the Army of Tennessee, 1861-1865 (Tuscaloosa: The University of Alabama Press

  14. Krasnotur'insk Skarn copper ore field, Northern Urals: The U-Pb age of ore-controlling diorites and their place in the regional metallogeny

    NASA Astrophysics Data System (ADS)

    Grabezhev, A. I.; Ronkin, Yu. L.; Puchkov, V. N.; Gerdes, A.; Rovnushkin, M. Yu.

    2014-06-01

    The Krasnotur'insk skarn copper ore field known from the theoretical works of Academician K.S. Korzhinskii is located in the western part of the Tagil volcanic zone (in the area of the town of Krasnotur'insk). The ore field is composed of layered Devonian (Emsian) volcanosedimentary rocks intruded by small plutons of quartz diorites, diorites, and gabbrodiorites. Widespread pre-ore and intra-ore dikes of similar composition control the abundance of the andradite skarns formed after limestones and the magnetitesulfide and sulfide ore bodies formed after skarns. The LA-ICP-MS U-Pb concordant age of zircon from the quartz diorite of the Vasil'evsko-Moskalevskii pluton calculated by 16 analyses (16 crystals) is 407.7 ± 1.6 Ma (MSWD = 1.5). Taking into account the geological and petrogeochemical similarity of diorites of small plutons and intra-ore dikes, it is assumed that this age corresponds to the period of formation of the ore-magmatic system of the Krasnotur'insk skarn copper ore field. It was probably formed somewhat earlier than the Auerbakh montzonitic pluton and the accompanying skarn magnetite deposits in the south.

  15. Assessment of Angelica sinensis (Oliv.) Diels as a repellent for personal protection against mosquitoes under laboratory and field conditions in northern Thailand.

    PubMed

    Champakaew, Danita; Junkum, Anuluck; Chaithong, Udom; Jitpakdi, Atchariya; Riyong, Doungrat; Wannasan, Anchalee; Intirach, Jitrawadee; Muangmoon, Roongtawan; Chansang, Arpaporn; Tuetun, Benjawan; Pitasawat, Benjawan

    2016-06-29

    Angelica sinensis (Oliv.) hexane extract (AHE) has been reported as a proven and impressive repellent against laboratory-reared female Aedes aegypti mosquitoes. With the aim of promoting products of plant origin as a viable alternative to conventional synthetic substances, this study was designed to transform AHE-based repellents for exploitable commercial production by enhancing their efficacy and assessing their physical and biological stability as well as repellency against mosquitoes under laboratory and field conditions. The chemical profile of AHE was analyzed by qualitative gas chromatography-mass spectrometry (GC-MS) technique. AHE was supplemented with vanillin, as a fixative, and then investigated for repellency and comparison to the standard synthetic repellent, DEET, under both laboratory and field conditions. Determination of physical and biological stability as a repellent was carried out after keeping AHE samples under varying temperatures and for different storage times. GC-MS analysis revealed that AHE contained at least 21 phytochemical compounds, constituting 95.74 % of the total content, with the major constituent of 3-N-butylphthalide (66.67 %). Ethanolic formulations of AHE and DEET showed improvement of repellency in a dose-dependent manner when vanillin was added in laboratory assessment. While 5-25 % AHE alone provided median complete-protection times of 2.0-6.5 h against Ae. aegypti, these times were increased to 4.0-8.5 h with a combination of AHE and 5 % vanillin (AHEv). Protection times against Ae. aegypti were extended from 2.25 to 7.25 h to 4.25-8.25 h when 5-25 % DEET was combined with 5 % vanillin (DEETv). In determining stability, all stored AHE samples exhibited similar characteristics such as liquid phases with aromatic odor comparable to those of fresh preparations. Furthermore, repellent activity of stored AHE samples lasted for at least six months, with varied efficacy (4.5-10.0 h) against Ae. aegypti. Field trials

  16. Digital Geology from field to 3D modelling and Google Earth virtual environment: methods and goals from the Furlo Gorge (Northern Apennines - Italy)

    NASA Astrophysics Data System (ADS)

    De Donatis, Mauro; Susini, Sara

    2014-05-01

    A new map of the Furlo Gorge was surveyed and elaborated in a digital way. In every step of work we used digital tools as mobile GIS and 3D modelling software. Phase 1st Starting in the lab, planning the field project development, base cartography, forms and data base were designed in the way we thought was the best for collecting and store data in order of producing a digital n­-dimensional map. Bedding attitudes, outcrops sketches and description, stratigraphic logs, structural features and other informations were collected and organised in a structured database using rugged tablet PC, GPS receiver, digital cameras and later also an Android smartphone with some survey apps in-­house developed. A new mobile GIS (BeeGIS) was developed starting from an open source GIS (uDig): a number of tools like GPS connection, pen drawing annotations, geonotes, fieldbook, photo synchronization and geotagging were originally designed. Phase 2nd After some month of digital field work, all the informations were elaborated for drawing a geologic map in GIS environment. For that we use both commercial (ArcGIS) and open source (gvSig, QGIS, uDig) without big technical problems. Phase 3rd When we get to the step of building a 3D model (using 3DMove), passing trough the assisted drawing of cross-­sections (2DMove), we discovered a number of problems in the interpretation of geological structures (thrusts, normal faults) and more in the interpretation of stratigraphic thickness and boundaries and their relationships with topography. Phase 4th Before an "on­-armchair" redrawing of map, we decide to go back to the field and check directly what was wrong. Two main vantages came from this: (1) the mistakes we found could be reinterpreted and corrected directly in the field having all digital tools we need; (2) previous interpretations could be stored in GIS layers keeping memory of the previous work (also mistakes). Phase 5th A 3D model built with 3D Move is already almost self

  17. Flooded area and plant zonation in isolated wetlands in well fields in the Northern Tampa Bay Region, Florida, following reductions in groundwater-withdrawal rates

    USGS Publications Warehouse

    Haag, Kim H.; Pfeiffer, William R.

    2012-01-01

    WAP scores and weighted average scores for wetland vegetation were generally consistent with the results of the flooded area analysis. The WAP scores and weighted average scores were higher overall and did not decline with time at four wetlands in well fields (W-33, W-56, Starkey N, and Starkey 108) during the years following reductions in groundwater-withdrawal rates. These four wetlands also had increases in the extent and duration of the flooded area during the post-reduction period. Scores for trees were more consistent than scores for shrubs and groundcover. WAP scores remained relatively low or generally declined at five well-field wetlands (Q-1, W-17, W-41, Starkey D, and Starkey E) during the years following reductions in groundwater-withdrawal rates, and weighted average scores either declined over time or remained low. These five wetlands either did not have an increase in the extent and duration of the flooded area, or if there was an increase, it was small.

  18. Anisotropy of Magnetic Susceptibility (AMS) of Carbonate Rocks as a Proxy for the Strain Field near the Dead Sea Transform in Northern Israel

    NASA Astrophysics Data System (ADS)

    Issachar, Ran; Levi, Tsafrir; Weinberger, Ram; Marco, Shmuel

    2014-05-01

    To exploit the potential of anisotropy of magnetic susceptibility (AMS) axes (k1, k2, k3) and magnitudes as a tool to estimate the strain field around major faults, the AMS of calcite-bearing diamagnetic rocks that crop out next to the Dead Sea Transform (DST) were measured. The low-field bulk-susceptibility of Bar-Kokhba limestone formation is -10.67±1.69 [µSI], very close to the value of a single calcite crystal. Thermomagnetic curves show temperature independent and reversible behavior. Chemical composition analysis indicates minor amounts of Fe contents <300 ppm. Results of XRD diffraction and petrofabric study of thin-sections and SEM images indicate that the Bar-Kokhba rocks are calcite mono-mineralic rocks. The magnetic fabrics are solely controlled by the alignment of c-axes of almost pure calcite crystals and help to assess the direction of the maximum shortening prevailing post-deposition and during the tectonic evolution of the DST. In one studied site, high Fe contents <6000 ppm were found, which are associated with young morphological processes of chemical alteration. In this site, thermomagnetic curves indicate temperature dependency and irreversibility. IRM curves show saturation around 200 mT, evidence of ferro/ferimagnetic minerals. AARM measurements reveal isotropic fabric which suggesting that the ferro/ferimagnetic minerals are contributing no anisotropy to the AMS. The AMS of the diamagnetic fabric is masked by a paramagnetic fabric of Fe-bearing minerals. Using liner correlation between Fe content and bulk susceptibility we applied a novel tensor subtraction method and successfully isolated the diamagnetic fabric from the total AMS. The paramagnetic fabric has characteristics of sedimentary fabrics, while that of the diamagnetic fabric has tectonic characteristics. The isolation process indicates that the AMS of carbonate rocks is mostly controlled by the diamagnetic phase, where the Fe content is below 500 ppm. Differences in the degree of

  19. Genotoxicity and cytotoxicity reduction of the polluted urban river after ecological restoration: a field-scale study of Jialu River in northern China.

    PubMed

    Sun, Jie; Zhang, Rui; Qin, Long; Zhu, Haixiao; Huang, Yu; Xue, Yingang; An, Shuqing; Xie, Xianchuan; Li, Aimin

    2017-01-13

    To further treat the reclaimed municipal wastewater and rehabilitate the aquatic ecosystem of polluted urban rivers, an 18.5-km field-scale ecological restoration project was constructed along Jialu River, a polluted urban river which receives only reclaimed municipal wastewater from Zhengzhou City without natural upland water dilution. This study investigated the potential efficiency of water quality improvement, as well as genotoxicity and cytotoxicity reduction along the ecological restoration project of this polluted urban river. Results showed that the chemical oxygen demand (COD) and ammonia nitrogen (NH3-N) of the reclaimed municipal effluent were reduced by more than 45 and 70%, respectively, meeting the Chinese surface water environmental quality standard level IV, while the total phosphorus and metal concentrations had no significant reduction along the restoration project, and Pb concentrations in all river water samples exceeded permissible limit in drinking water set by WHO (2006) and China (GB5749-2006). The in vitro SOS/umu assay showed 4-nitroquinoline-1-oxide equivalent (4-NQO-EQ) values of reclaimed municipal wastewater of 0.69 ± 0.05 μg/L in April and 0.68 ± 0.06 μg/L in December, respectively, indicating the presence of genotoxic compounds. The results of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and hepatic cell apoptosis in zebrafish after a chorionic long-term (21 days) in vivo exposure also demonstrated that the reclaimed municipal wastewater caused significant DNA oxidative damage and cytotoxicity. After the ecological purification of 18.5-km field-scale restoration project, the genotoxicity assessed by in vitro assay was negligible, while the DNA oxidative damage and cytotoxicity in exposed fish were still significantly elevated. The mechanisms of DNA oxidative damage and cytotoxicity caused by the reclaimed municipal wastewater need further study.

  20. Geochemistry and diagenesis of stratabound calcite cement layers within the Rannoch Formation of the Brent Group, Murchison Field, North Viking Graben (northern North Sea)

    NASA Astrophysics Data System (ADS)

    Prosser, D. J.; Daws, J. A.; Fallick, A. E.; Williams, B. P. J.

    1993-11-01

    Up to four calcite-cemented horizons (doggers) form impermeable barriers to fluid flow within the Middle Jurassic Rannoch Formation and are correlatable across the Murchison Field. Calcite precipitated during early diagenesis, within high porosity/permeability sandstones at the top of coarsening (shoaling) upward shoreface cycles. Calcite δ 13C and δ 18O compositions range from -4.1 to -13.4‰ PDB, and -6.6 to -16.7‰ PDB, respectively. Sr concentrations of up to 1334 ppm are consistent with marine carbonate sources (probably shell fragments), but no viable intraformational carbonate source has been identified in the Murchison Field area. Initial 87Sr/ 86Sr compositions (0.71109-0.71266) are higher than Middle Jurassic seawater (0.7073), and consistent with precipitation from modified porewaters containing significant proportions of continentally derived "meteoric" fluids enriched in 87Sr as a result of basement weathering, or percolation through hinterland soils/unconsolidated detritus. An internal source of 87Sr is not considered viable in view of the high proportion (up to 25‰ clastic constituents) of unaltered detrital alkali feldspar and mica within the Rannoch Formation. Geochemical and isotope data indicate correlations between increasing δ 18O composition and increasing iron and magnesium content within calcite. Calcium concentrations decrease with increasing δ 18O for calcites. Geochemical data trends can be interpreted differently in terms of either "static" or "evolving" δ 18O porewater models. Static δ 18O porewater models using Jurassic/Early Cretaceous "meteoric" water ( δ 18O = -6‰; SMOW) predict cement precipitation temperatures of 17-77°C. However, δ 13C compositions are more depleted than those typical of carbon derived from shell debris, and correlation between decreasing δ 18O and decreasing δ 13C suggests modification of a meteoric-derived porewater system during burial via contribution of low δ 13C carbon derived from a deep

  1. Tectono-sedimentary evolution of an extensional basin revealed by a combined photo-geological and field-mapping approach. The Montefalco Basin (Northern Apennines, Italy)

    NASA Astrophysics Data System (ADS)

    Bucci, Francesco; Mirabella, Francesco; Santangelo, Michele; Cardinali, Mauro; Guzzetti, Fausto

    2016-04-01

    the evolution of the basin. Furthermore, results demonstrate that integration of accurate photo-geological maps produced through API and geological field mapping, can contribute to: (i) characterize the tectono-stratigraphic architecture and the geomorphological evolution of continental basins, (ii) help mineral reserves investigation, (iii) provide new input for active tectonic studies, (iv) produce new geological maps in other continental and marine basins, where field data are hard to collect.

  2. Changes in Microbial and Phytoplankton Communities in Response to Oil and Nutrients in the Northern Gulf of Mexico: Correlating Experiments With Field Observations.

    NASA Astrophysics Data System (ADS)

    D'Souza, N.; Weber, S.; Subramaniam, A.; Juhl, A. R.; Montoya, J. P.

    2016-02-01

    Natural hydrocarbon seeps account for around 47% of the oil released into the environment, with seeps in the Gulf of Mexico releasing up to 1.1×108 L oil year-1. Our previous work in the Gulf of Mexico has linked natural hydrocarbon seepage occurring at depths exceeding 1000 meters to elevations in surface and sub-surface chlorophyll concentrations in the upper water column via plume-driven upwelling of nutrient rich waters from depth. Subsequent experiments further revealed synergistic impacts of oil, nutrients, and microbial predation on surface microbial growth rates and metabolism - suggesting an additional top-down control on surface bacteria and microbes. While the magnitude of each contribution remains unclear, both, bottom-up and top-down mechanisms associated with natural oil seepage are evident. We build on our previous findings with results from microcosm experiments aimed at dissecting out the influence of nitrate, phosphate, silica, and crude oil on microbes in surface waters. Changes in phytoplankton populations, bacterial growth rates, and the subsequent drawdown of nutrients in these microcosms are presented here in context of field measurements made at natural seeps.

  3. The questa magmatic system: Petrologic, chemical and isotopic variations in cogenetic volcanic and plutonic rocks of the latir volcanic field and associated intrusives, northern New Mexico

    SciTech Connect

    Johnson, C.M.

    1986-01-01

    Field, chemical and isotopic data demonstrate that nearly all igneous rocks at Questa resulted from interactions between mantle-derived parental magmas and the crust. Strontium, neodymium and lead isotope ratios of early andesites to rhyolites (28 to 26 Ma) indicate that these magmas assimilated > 25% lower crust. Injection of basaltic magmas extensively modified the strontium and neodymium but not the lead isotope compositions of the lower crust. Eruption of comendite magmas and the peralkaline Amalia Tuff 26 Ma is correlated with inception of regional extension. Lead isotope ratios identify different sources for the metaluminous granites and the peralkaline rocks. 26 Ma metaluminous granite to granodiorite intrusions have chemical and isotopic compositions to those of the precaldera intermediate-composition rocks, and are interpreted as representing the solidified equivalents of the precaldera magmatic episode. However, both conventional and ion-microprobe isotopic data prohibit significant assimilation of crustal rocks at the level of exposure, suggesting that the plutons were emplaced a relatively crystal-rich mushes which did not have sufficient heat to assimilate country rocks. This suggest that in some cases plutonic rocks are better than volcanic rocks in representing the isotopic compositions of their source regions, because the assimilation potential of crystal-rich magmas is significantly less than that of largely liquid magmas.

  4. Water budgets and groundwater volumes for abandoned underground mines in the Western Middle Anthracite Coalfield, Schuylkill, Columbia, and Northumberland Counties, Pennsylvania-Preliminary estimates with identification of data needs

    USGS Publications Warehouse

    Goode, Daniel J.; Cravotta, Charles A.; Hornberger, Roger J.; Hewitt, Michael A.; Hughes, Robert E.; Koury, Daniel J.; Eicholtz, Lee W.

    2011-01-01

    This report, prepared in cooperation with the Pennsylvania Department of Environmental Protection (PaDEP), the Eastern Pennsylvania Coalition for Abandoned Mine Reclamation, and the Dauphin County Conservation District, provides estimates of water budgets and groundwater volumes stored in abandoned underground mines in the Western Middle Anthracite Coalfield, which encompasses an area of 120 square miles in eastern Pennsylvania. The estimates are based on preliminary simulations using a groundwater-flow model and an associated geographic information system that integrates data on the mining features, hydrogeology, and streamflow in the study area. The Mahanoy and Shamokin Creek Basins were the focus of the study because these basins exhibit extensive hydrologic effects and water-quality degradation from the abandoned mines in their headwaters in the Western Middle Anthracite Coalfield. Proposed groundwater withdrawals from the flooded parts of the mines and stream-channel modifications in selected areas have the potential for altering the distribution of groundwater and the interaction between the groundwater and streams in the area. Preliminary three-dimensional, steady-state simulations of groundwater flow by the use of MODFLOW are presented to summarize information on the exchange of groundwater among adjacent mines and to help guide the management of ongoing data collection, reclamation activities, and water-use planning. The conceptual model includes high-permeability mine voids that are connected vertically and horizontally within multicolliery units (MCUs). MCUs were identified on the basis of mine maps, locations of mine discharges, and groundwater levels in the mines measured by PaDEP. The locations and integrity of mine barriers were determined from mine maps and groundwater levels. The permeability of intact barriers is low, reflecting the hydraulic characteristics of unmined host rock and coal. A steady-state model was calibrated to measured groundwater

  5. Quantitative Interpretation of Arctic Tundra Attributes Using Remote Sensing: Leveraging Field Data, Modern- and Legacy Landsat Data, and Commercial Imagery in Northern Alaska

    NASA Astrophysics Data System (ADS)

    Frost, G. V., Jr.; Macander, M. J.; Nelson, P. R.

    2014-12-01

    Integrated analysis of ground-based vegetation data and remote sensing supports vegetation mapping, landscape-change detection, wildlife habitat assessment, and tracking of phenological events such as green-up and senescence. The life-cycles of tundra plants occur within a highly compressed seasonal window, making the quantitative assessment of vegetation and landscape attributes from ≤30m resolution remotely-sensed imagery, such as above-ground biomass, % shrub cover, and % surface water, a difficult task when applied across large study domains. To support mapping of vegetation and landscape attributes across ~100,000 km2 of Alaska's North Slope, we obtained ground data for tundra vegetation using a point-intercept sampling approach across a network of 107 field plots spanning gradients of bioclimate, landscape position (upland, lowland, riverine), and geomorphic setting (foothills, coastal plain). At each plot, vegetation data were collected along three 50-m linear transects, compatible with 30-m Landsat imagery. We summarized live vegetation, litter, and non-vegetated surfaces using three terms: top cover (uppermost "hit"), percent cover (total areal cover along transect), and hit density (all "hits" at a point). We then evaluated a suite of data models (e.g., General Additive Models, classification tree, clustering) and data-mining approaches (e.g., neural networks, random forest) using midsummer Landsat TM/ETM+ acquisitions since 1985, and OLI acquisitions for 2013-2014. The large size, frequent cloudiness, and interannual variability of the study area necessitated the compositing of a multitude of Landsat scenes. A median NDVI compositing technique was used to select Landsat observations from cloud- and shadow-free pixels that met day-of-year and year constraints. This technique produced seamless, phenologically consistent composites that are largely free of artifacts and suitable for regional-scale analysis. Ground-based training data and an archive of

  6. The polycyclic Lausche Volcano (Lausitz Volcanic Field) and its message concerning landscape evolution in the Lausitz Mountains (northern Bohemian Massif, Central Europe)

    NASA Astrophysics Data System (ADS)

    Wenger, Erik; Büchner, Jörg; Tietz, Olaf; Mrlina, Jan

    2017-09-01

    The Tertiary Lausitz Volcanic Field covers a broad area encompassing parts of Eastern Saxony (Germany), Lower Silesia (Poland) and North Bohemia (Czech Republic). Volcanism was predominantly controlled by the volcano-tectonic evolution of the Ohře Rift and culminated in the Lower Oligocene. This paper deals with the highest volcano of this area, the Lausche Hill (792.6 m a.s.l.) situated in the Lausitz Mountains. We offer a reconstruction of the volcanic edifice and its eruptive history. Its complex genesis is reflected by six different eruption styles and an associated petrographic variety. Furthermore, the Lausche Volcano provides valuable information concerning the morphological evolution of its broader environs. The remnant of an alluvial fan marking a Middle Paleocene-Lower Eocene (62-50 Ma) palaeo-surface is preserved at the base of the volcano. The deposition of this fan can be attributed to a period of erosion of its nearby source area, the Lausitz Block that has undergone intermittent uplift at the Lausitz Overthrust since the Upper Cretaceous. The Lausche Hill is one of at least six volcanoes in the Lausitz Mountains which show an eminent low level of erosion despite their Oligocene age and position on elevated terrain. These volcanoes are exposed in their superficial level which clearly contradicts their former interpretation as subvolcanoes. Among further indications, this implies that the final morphotectonic uplift of the Lausitz Mountains started in the upper Lower Pleistocene ( 1.3 Ma) due to revived subsidence of the nearby Zittau Basin. It is likely that this neotectonic activity culminated between the Elsterian and Saalian Glaciation ( 320 ka). The formation of the low mountain range was substantially controlled by the intersection of the Lausitz Overthrust and the Ohře Rift.

  7. Plant betterment for an anthracite-burning utility in Ukraine: Coal preparation as part of a SO{sub 2}, NO{sub x}, and particulate emission control strategy

    SciTech Connect

    Ruether, J.A.; Freeman, M.C.; Gollakota, S.V.

    1997-12-31

    Workers at the Energy Departments of the US and Ukraine have cooperatively devised a strategy for upgrading performance of a 200 MWe wet bottom pulverized coal boiler in eastern Ukraine at the Lugansk GRES power station. The plant currently burns poor quality anthracite (30% ash versus 18% ash design coal, as-received basis) and is in need of maintenance. Oil or gas support fuel in the amount of 30% (calorific basis) is required to stabilize the flame and supplement the calorific value of the coal feed. No NO{sub x} or SO{sub 2} controls are used at present, and unburned carbon content in the fly ash is high. An experimental program was carried out at the Federal Energy Technology Center (FETC) to estimate the improvement in plant performance that could be expected if the unit is supplied with design coal and is refurbished. High ash Ukrainian anthracite was cleaned to design specifications. Raw and cleaned coal were fed to a 490 MJ/h coal feed combustion unit at a number of conditions of support fuel use and ingress air leakage designed to simulate current and improved operations at the power plant. The results indicate the improvement in performance and reductions in SO{sub 2} and NO{sub x} emissions that can be expected as a result of the planned upgrade and conversion to use of cleaned coal. A detailed engineering and financial analysis indicates that plant rehabilitation combined with the use of cleaned schtib reduces not only pollutant emissions but also cost of electricity (COE). Additional benefits include increased plant life and capacity, and reduced supplementary fuel consumption.

  8. Isolated Northern Dunes

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    This VIS image was taken at 81 degrees North latitude during Northern spring. In this region, the dunes are isolated from each other. The dunes are just starting to emerge from the winter frost covering appearing dark with bright crests. These dunes are located on top of ice.

    Image information: VIS instrument. Latitude 82.1, Longitude 191.3 East (168.7 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  9. Northern Sand Sea

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    This VIS image was taken at 82 degrees North latitude during Northern spring. The image is completely dominated by dunes. In sand seas, it is very common for a single type of dune to occur, and for a single predominate wind to control the alignment of the dunes.

    Image information: VIS instrument. Latitude 82.2, Longitude 152.5 East (207.5 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  10. Field testing and adaptation of a methodology to measure "in-stream" values in the Tongue River, northern Great Plains (NGP) region

    USGS Publications Warehouse

    Bovee, Ken D.; Gore, James A.; Silverman, Arnold J.

    1978-01-01

    A comprehensive, multi-component in-stream flow methodology was developed and field tested in the Tongue River in southeastern Montana. The methodology incorporates a sensitivity for the flow requirements of a wide variety of in-stream uses, and the flexibility to adjust flows to accommodate seasonal and sub-seasonal changes in the flow requirements for different areas. In addition, the methodology provides the means to accurately determine the magnitude of the water requirement for each in-stream use. The methodology can be a powerful water management tool in that it provides the flexibility and accuracy necessary in water use negotiations and evaluation of trade-offs. In contrast to most traditional methodologies, in-stream flow requirements were determined by additive independent methodologies developed for: 1) fisheries, including spawning, rearing, and food production; 2) sediment transport; 3) the mitigation of adverse impacts of ice; and 4) evapotranspiration losses. Since each flow requirement varied in important throughout the year, the consideration of a single in-stream use as a basis for a flow recommendation is inadequate. The study shows that the base flow requirement for spawning shovelnose sturgeon was 13.0 m3/sec. During the same period of the year, the flow required to initiate the scour of sediment from pools is 18.0 m3/sec, with increased scour efficiency occurring at flows between 20.0 and 25.0 m3/sec. An over-winter flow of 2.83 m3/sec. would result in the loss of approximately 80% of the riffle areas to encroachment by surface ice. At the base flow for insect production, approximately 60% of the riffle area is lost to ice. Serious damage to the channel could be incurred from ice jams during the spring break-up period. A flow of 12.0 m3/sec. is recommended to alleviate this problem. Extensive ice jams would be expected at the base rearing and food production levels. The base rearing flow may be profoundly influenced by the loss of streamflow

  11. Fertilization of Northern Hardwoods

    Treesearch

    R. Lea; D.G. Brockway

    1986-01-01

    Northern hardwoods grow over a considerable range of climatic and edaphic conditions and exhibit a wide range in productivity.Many northern hardwood forests are capable of high production relative to other forest types, but are often slow to reach maximum productivity because of low nutrient availability.Altering the patterns of biomass accumulation so that managers...

  12. What are northern hardwoods?

    Treesearch

    Richard M. Godman

    1992-01-01

    The term "northern hardwoods" was used in the early 1900's to separate the hardwoods of the northern region from those growing in the South. With continued usage in the North the term now represents all dense hardwood species both in the Lake States and Northeast. Unfortunately, this has complicated describing and applying silvicultural practices for...

  13. Field guide to sedimentary structures in the Navajo and Entrada sandstones in southern Utah and northern Arizona: Chapter in Field-trip guidebook, 100th annual meeting, The Geological Society of America, Phoenix, Arizona, October 26-29, 1987

    USGS Publications Warehouse

    Rubin, David M.; Hunter, Ralph E.

    1987-01-01

    This field-trip guide describes the common sedimentary structures that occur in eolian sands. The outcrops that are described occur in the Navajo and Entiaia Sandstones between the areas of Page, Arizona and St. George, Utah (figure I), but the sedimentary structures of these two sandstones are typical of most eolian deposits. The main part of the guide discusses the geologic setting and the origin of the various structures, and the road log discusses which structures are best displayed at selected outcrops.

  14. Seasonal Changes in Northern Mars Dune Field

    NASA Image and Video Library

    2011-02-03

    Three images of the same location, taken by NASA Mars Reconnaissance Orbiter at different times on Mars, show seasonal activity causing sand avalanches and ripple changes on a Martian dune. Time sequence of the images progresses from top to bottom.

  15. Silvicultural guide for northern hardwoods in the northeast

    Treesearch

    William B. Leak; Mariko Yamasaki; Robbo. Holleran

    2014-01-01

    This revision of the 1987 silvicultural guide includes updated and expanded silvicultural information on northern hardwoods as well as additional information on wildlife habitat and the management of mixed-wood and northern hardwood-oak stands. The prescription methodology is simpler and more field-oriented. This guide also includes an appendix of familiar tables and...

  16. A revision of the Axylus group of Agraeciini (Orthoptera: Tettigoniidae: Conocephalinae) and of some other species formerly included in Nicsara or Anthracites Revision of the Indo-Australian Conocephalinae, Part 3.

    PubMed

    Ingrisch, Sigfrid

    2015-11-23

    Axylus group is used to include the five genera Axylus Stål, 1877, Anthracites Redtenbacher, 1891 sensu stricto, Eucoptaspis Willemse, 1966, Eulobaspis gen. nov., and Heminicsara Karny, 1912. It is mainly based on a combination of the characters shape of pronotum, spiniform meso- and metasternal lobes, and similar basic ground plans of the male cerci, titillators and female subgenital plates. The five genera together with two superficially similar genera Euanthracites gen. nov. and Sulasara gen. nov. are fully revised. Papuacites gen. nov. is proposed for two New Guinean species formerly included in Anthracites. Nicsara Walker, 1869 is restricted to Australian species; Spinisternum Willemse, 1942 is synonymised with Heminicsara Karny, 1912; Odontocoryphus Karny, 1907 based on two nymphs is synonymised with Macroxiphus Pictet, 1888; Pseudoliara Karny, 1907 described after one nymph is regarded incertae sedis. 40 new combination of species are proposed: Axylus bimaculatus (Redtenbacher, 1891) comb. nov., A. inferior (Brunner, 1898) comb. nov., A. inflatus (Brunner, 1898) comb. nov., A. loboensis (De Haan, 1842) comb. nov., A. minutus (Dohrn, 1905) comb. nov., A. nigrifrons (Brunner, 1898) comb. nov., A. philippinus (Hebard, 1922) comb. nov., A, taylori (Hebard, 1922) comb. nov., and A. thoracicus (Dohrn, 1905) comb. nov. (all from Nicsara); Euanthracites apoensis (Hebard, 1922) comb. nov., E. femoralis (Dohrn, 1905) comb. nov., E. rufus (Ingrisch, 1998) comb. nov., and E. tibialis (Karny, 1931) comb. nov. (from Anthracites); Eucoptaspis inexpectatus (Willemse, 1953) comb. nov. (from Gonatacanthus Karny, 1907); Eulobaspis dehaani (Karny, 1920) comb. nov., E. emarginata (Karny, 1926) comb. nov., E. moluccana (Redtenbacher, 1891) comb. nov., E. personata (Karny, 1926) comb. nov., E. quadrimaculata (Karny, 1926) comb. nov., E. rotundata (Karny, 1926) comb. nov., and E. strigatipes (Bolivar, 1898) comb. nov. (from Nicsara); Eulobaspis lobaspoides (Karny, 1907) comb. nov

  17. Placing our northern hardwood woodlots under management

    Treesearch

    Russell J. Hutnik

    1956-01-01

    Do you own a woodlot? Does it contain mostly northern hardwoods - that is, beech, birch, maple, and ash, with some hemlock and spruce? If the answers to these two questions are "yes," then you may be interested in the work that is carried on at the Bartlett Experimental Forest in New Hampshire. This is one of the field laboratories established by the U. S....

  18. Temperature field around a laser-heated coal particle

    SciTech Connect

    Feng, B.; Liu, Y.H.; Zhou, Y.B.; Liu, Z.H.; Zheng, C.G.

    1997-12-31

    Holography was used to measure the temperature field around a laser heated coal particle. A man-made coal particle (with the size of 5mm in diameter and 5mm in length) was ignited by a laser beam (with the maximum power of 15W). And then the temperature distribution around the particle was obtained from the holograph which was developed by the authors. A bituminous coal, an anthracite and a sub-bituminous coal were used. It was interesting to find that there exists a zone near the particle surface where the temperature is higher than that at the surface for the bituminous coal during the combustion of the coal although the phenomenon was not found for the other coals. A mathematical model taking into account the laser induced energy was developed to calculate the temperature field around the particle. The predicted results were compared with the experimental ones.

  19. The Northern Manitoba Mining Academy

    NASA Astrophysics Data System (ADS)

    Alexandre, Paul

    2017-04-01

    The Northern Manitoba Mining Academy (NMMA, miningacademy.ca) is a new educational institution located in Flin Flon, Manitoba. It is associated with the University College of the North and is specifically intended to serve the needs of the Northern Manitoban communities with regards to job creation by providing training in a variety of mining, construction, and exploration related areas. NMMA's mission is to provide innovative and responsible solutions for the creation of a knowledgeable, skilled, and sustainable workforce within a vibrant, mineral-rich resource industry. It facilitates strategic training initiatives and research activities in order to strengthen the social, economic, and environmental benefits of a robust mining and resources sector. In terms of education, NMMA offers its own programs, mostly short courses in health and safety, courses organized by the University College of the North (wilderness safety, prospecting, and exploration), and courses organized in association with provincial Industries-Based Safety Programs and Associations (a variety of construction-related trades). However, the programming is not limited to those courses already on the syllabus: the Academy operates on open-doors policy and welcomes people with their unique and diverse needs; it prides itself in its ability to tailor or create specific on-demand courses and deliver them locally in the North. The Northern Manitoba Mining Academy also provides access to its world-class facilities for field-based undergraduate courses, as well as graduate students and researchers doing field work. Full sample preparation facilities are offered to students and scientists in all natural and environmental sciences.

  20. Northern Trust Mines

    EPA Pesticide Factsheets

    The United States and the Navajo Nation entered into settlement agreements that provide funds to conduct investigations and any needed cleanup at 16 of the 46 priority mines, including six mines in the Northern Abandoned Uranium Mine Region.

  1. Northern Arizona Volcanoes

    NASA Image and Video Library

    2006-05-01

    Northern Arizona is best known for the Grand Canyon. Less widely known are the hundreds of geologically young volcanoes, at least one of which buried the homes of local residents. This image was acquired by NASA Terra spacecraft.

  2. Spotting Saturn Northern Storm

    NASA Image and Video Library

    2011-07-06

    NASA Cassini spacecraft captures a composite near-true-color view of the largest and most intense storm observed on Saturn. The storm is seen churning through the atmosphere in Saturn northern hemisphere.

  3. Groundwater management in northern Iraq

    NASA Astrophysics Data System (ADS)

    Stevanovic, Zoran; Iurkiewicz, Adrian

    2009-03-01

    Groundwater is vital and the sole resource in most of the studied region of northern Iraq. It has a significant role in agriculture, water supply and health, and the elimination of poverty in rural areas. Although Iraq is currently dramatically disturbed by complex political and socio-economic problems, in its northern part, i.e. the Kurdish-inhabited region, fast urbanization and economic expansion are visible everywhere. Monitoring and water management schemes are necessary to prevent aquifer over-exploitation in the region. Artificial recharge with temporary runoff water, construction of subsurface dams and several other aquifer management and regulation measures have been designed, and some implemented, in order to improve the water situation. Recommendations, presented to the local professionals and decision-makers in water management, include creation of Water Master Plans and Water User Associations, synchronization of drilling programmes, rehabilitation of the existing well fields, opening of new well fields, and the incorporation of new spring intakes in some areas with large groundwater reserves, as well as construction of numerous small-scale schemes for initial in situ water treatment where saline groundwater is present.

  4. Petroleum resource potential GIS of northern Afghanistan

    USGS Publications Warehouse

    Steinshouer, Douglas W.; Klett, Timothy R.; Ulmishek, Gregory F.; Wandrey, Craig J.; Wahl, Ronald R.; Hill, Ronald J.; Pribil, Michael J.; Pawlewicz, Mark J.; King, J. David; Agena, Warren F.; Taylor, David J.; Amirzada, Abdulla; Selab, Amir Mohammad; Mutteh, Abdul-Salam; Haidari, Ghulam Naqshband; Wardak, Moeengul Gullabudeen

    2006-01-01

    The CD-ROM contains an ESRI ArcReader format GIS project presenting the results of a petroleum resource assessment of Northern Afghanistan, and other data used in the petroleum assessment. Geologic, structural, field, well, political, and other GIS layers covering Afghanistan, Northern Afghanistan and adjacent areas, along with associated geochemical and other data tables pertinent to a petroleum assessment are included. The purpose of this GIS is to provide the basic data layers and tables required to support the petroleum assessment, data for further exploration and development, and an index of known data.

  5. Evidence for recent populations bottlenecks in northern spotted owls (Strix occidentalis Caurina)

    Treesearch

    W.Chris Funk; Eric D. Forsman; Matthew Johnson; Thomas D. Mullins; Susan M.. Haig

    2009-01-01

    The northern spotted owl (Strix occidentalis caurina) is one of the most controversial threatened subspecies ever listed under the US Endangered Species Act. Despite protection of its remaining forest habitat, recent field studies show continued declines of northern spotted owls. One potential threat to northern spotted owls which has not yet been...

  6. Definition and kinematics of the northern of the Puerto Rico-Virgin Islands block and the Lesser Antilles forearc based on an updated and improved GPS velocity field and revised block models

    NASA Astrophysics Data System (ADS)

    Mattioli, G. S.; Jansma, P. E.; Stafford-Glenn, M.; Calais, E.

    2011-12-01

    The presence of small tectonic blocks the Greater Antilles, for example the Puerto Rico-Virgin Islands block (PRVI), which may be translating, rotating, and possibly internally deforming, has been proposed and some cases well-documented by several workers. In addition, the existence of a Lesser Antilles forearc has been proposed based on interplate earthquake slip vectors (Lopez et al. 2006). Manaker et al. (2008) used sparse GPS and earthquake slip data from the northeastern Caribbean to construct a DEFNODE block and fault model to constrain interseismic fault coupling among the microplates in the northeastern Caribbean. They concluded that the Enriquillo fault in Haiti could produce a Mw7.2, if the entire accumulated elastic strain was released in one event. On January 12, 2010, the strain was released in a Mw7.0 earthquake that left Port-au-Prince in rubble. The interseismic GPS velocity field has been updated for Hispanolia (Calais et al, 2010); in addition, new data have been collected in the northern Lesser Antilles (NLA) in 2009 as well as throughout the PRVI block in 2007 and 2011, and the existing GPS time series updated and transformed into ITRF05 (IGS05). GPS data from the NLA are consistent with a NLA forearc sliver that moves differently from the Caribbean and North American plates as originally proposed by Lopez et al. (2006). The forearc does not, however, continue as single tectonic entity across the Anegada Passage as previously suggested. Here we report revised DEFNODE models using both the original geometry and constraints of Manaker et al. (2008) with an updated GPS data set as well as new models that explicitly include a forearc block. The models may be used to explicitly define the rotation parameters of the block as well as the coupling along block bounding faults. The original model geometry (without a forearc sliver) yields a higher reduced chi-squared (2.57 vs. 2.01), when additional the GPS velocities from NLA are used to condition the

  7. Phototaxis of larval and juvenile northern pike

    USGS Publications Warehouse

    Zigler, S.J.; Dewey, M.R.

    1995-01-01

    Age- Phi northern pike Esox lucius prefer vegetated habitats that are difficult to sample with standard towed gears. Light traps can be effective for sampling larval fishes in dense vegetation, given positive phototaxis of fish. We evaluated the phototactic response of young northern pike by comparing the catches of larvae and juveniles obtained with plexiglass traps deployed with a chemical light stick versus traps deployed without a light source (controls) in a laboratory raceway and in a vegetated pond. In the laboratory tests, catches of protolarvae and mesolarvae in lighted traps were 11-35 times greater than catches in control traps. The catches of juvenile northern pike in field and laboratory experiments were 3-15 times greater in lighted traps than in control traps, even though the maximum body width of the larger juveniles was similar to the width of the entrance slots of the traps (5 mm). Larval and juvenile northern pike were photopositive; thus, light traps should effectively sample age-0 northern pike for at least 6 weeks after hatching.

  8. Northern Plains of Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    22 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a typical view of the martian northern plains. Thousands of square kilometers of the northern middle and polar latitudes of Mars look similar to the scene in this image. In late spring and in summer, dust devils crisscross the northern plains, leaving a variety of dark streaks. The streaks do not survive from year to year, indicating their ephemeral nature. The circular features in this image, including the prominent bright circular feature near the bottom, are the locations of buried meteor impact craters. This image is located near 58.1oN, 207.6oW, and covers an area approximately 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  9. Northern Plains 'Crater'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    10 December 2004 The lower left (southwest) corner of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the location of a somewhat filled and buried meteor impact crater on the northern plains of Mars. The dark dots are boulders. A portion of a similar feature is seen in the upper right (northeast) corner of the image. This picture, showing landforms (including the odd mound north/northeast of the crater) that are typical of the martian northern lowland plains, was obtained as part of the MGS MOC effort to support the search for a landing site for the Phoenix Mars Scout lander. Phoenix will launch in 2007 and land on the northern plains in 2008. This image is located near 68.0oN, 227.4oW, and covers an area approximately 3 km (1.9 mi) wide. The scene is illuminated by sunlight from the lower left.

  10. Northern Arizona Volcanoes

    NASA Technical Reports Server (NTRS)

    2006-01-01

    Northern Arizona is best known for the Grand Canyon. Less widely known are the hundreds of geologically young volcanoes, at least one of which buried the homes of local residents. San Francisco Mtn., a truncated stratovolcano at 3887 meters, was once a much taller structure (about 4900 meters) before it exploded some 400,000 years ago a la Mt. St. Helens. The young cinder cone field to its east includes Sunset Crater, that erupted in 1064 and buried Native American homes. This ASTER perspective was created by draping ASTER image data over topographic data from the U.S. Geological Survey National Elevation Data.

    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 provides 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.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

    Size: 20.4 by 24.6 kilometers (12.6 by 15.2 miles) Location: 35.3 degrees North latitude, 111

  11. FACING NORTHEAST ACROSS NORTHERN END OF PARK TOWARDS ITS NORTHERN ...

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

    FACING NORTHEAST ACROSS NORTHERN END OF PARK TOWARDS ITS NORTHERN CORNER - Candler Park Historic District, Roughly bounded by Moreland, Dekalb, McLendon & Harold Avenues, Matthews Street & Clifton Terrace, Atlanta, Fulton County, GA

  12. Northern Arizona University

    ERIC Educational Resources Information Center

    Butcher, Michael F.; Saltonstall, Margot; Bickel, Sarah; Brandel, Rick

    2009-01-01

    Northern Arizona University (NAU) is a public university nestled below the San Francisco Peaks in Flagstaff, Arizona. It enrolls more than 21,000 undergraduate and graduate students at its main campus in Flagstaff, through its 35 statewide sites, and via online program offerings. Within the university organizational system, Student Affairs has a…

  13. Northern Arizona University

    ERIC Educational Resources Information Center

    Butcher, Michael F.; Saltonstall, Margot; Bickel, Sarah; Brandel, Rick

    2009-01-01

    Northern Arizona University (NAU) is a public university nestled below the San Francisco Peaks in Flagstaff, Arizona. It enrolls more than 21,000 undergraduate and graduate students at its main campus in Flagstaff, through its 35 statewide sites, and via online program offerings. Within the university organizational system, Student Affairs has a…

  14. Northern goshawk (Accipiter gentilis)

    Treesearch

    John R. Squires; Richard T. Reynolds

    1997-01-01

    The Northern Goshawk (hereafter referred to as Goshawk) is a large forest raptor, occupying boreal and temperate forests throughout the Holarctic. In North America, it breeds from Alaska to Newfoundland and south (Fig. 1). This partial migrant winters throughout its breeding range including occasionally the Great Plains and southeastern states; some...

  15. Survival and height growth of northern white-cedar from 18 provenances

    Treesearch

    Richard M. Jeffers

    1976-01-01

    Northern white-cedar from 18 provenances was evaluated for total height in the nursery and for survival and total height in two field plantings in northern Wisconsin and in western Upper Michigan. There were significant differences among provenances in survival at one location and in height at both field locations 5 years after planting; there were no differences among...

  16. Dermatophytosis in northern Africa.

    PubMed

    Nweze, E I; Eke, I

    2016-03-01

    Infections caused by dermatophytes are a global problem and a major public health burden in the world today. In Africa, especially in the northern geographical zone, dermatophytic infections are being reported at an alarming rate. This is mostly because of some local but unique cultural practices, socioeconomic and environmental conditions, lack of reliable diagnostic personnel and facilities and ineffective treatment. Interestingly, the pathogen spectrum and the clinical manifestation are most times different from what is seen in other continents. Several epidemiological studies have been performed on the incidence and aetiology of dermatophytoses in northern Africa. However, there is currently no review article with up-to-date information on the relevant findings reported so far in this region. This information is necessary for clinicians who treat dermatophytic infections all over the world since agents of dermatophytes are no longer restricted because of the rapid mobility of humans from one part of the world to another. Moreover, the epidemiology of dermatophytoses is known to change over time, thus requiring the update of information from time to time. A review of relevant studies published on dermatophytoses in northern Africa is presented. This covers all of old Sudan, Algeria, Egypt, Libya, Tunisia and Morocco.

  17. Northern Plains Patterns

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-513, 14 October 2003

    Patterns are common on the northern plains of Mars. Like their terrestrial counterparts in places like Siberia, Alaska, and northern Canada, patterned ground on Mars might be an indicator of the presence of ground ice. Whether it is true that the patterns on Mars are related to ground ice and whether the ice is still present beneath the martian surface are unknown. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows an example of patterned ground on the martian northern plains near 72.4oN, 252.6oW. The dark dots and lines are low mounds and chains of mounds. The circular feature near the center of the image is the location of a buried meteor impact crater; its presence today is marked only by the dark boulders on its rim and ejecta blanket that have managed to remain uncovered at the martian surface. The area shown is 3 km (1.9 mi) wide and illuminated by sunlight from the lower left.

  18. Commonwealth of the Northern Mariana Islands' forest resources, 2004

    Treesearch

    Joseph A. Donnegan; Sarah L. Butler; Olaf Kuegler; Bruce A. Hiserote

    2011-01-01

    The Forest Inventory and Analysis program collected, analyzed, and summarized field data on 37 field plots on the islands of Rota, Tinian, and Saipan in the Commonwealth of the Northern Mariana Islands (CNMI). Estimates of forest area, tree stem volume and biomass, the numbers of trees, tree damages, and the distribution of tree sizes were summarized for this...

  19. Preliminary vitrinite reflectance study of the post-Acadian Mapleton and Trout Valley Formation, northern Maine

    SciTech Connect

    Malinconico, M.L. . Dept. of Geology)

    1993-03-01

    Vitrinite reflectance was measured on plant fossils from the Devonian Mapleton and Trout Valley Formations in northern Maine in order to assess the degree and possible history of thermal maturation of these post-Acadian intermontane basin deposits, generally considered to be unmetamorphosed. The Middle Devonian Mapleton Formation, west of Presque Isle, lies within the prehnite-pumpellyite terrane of northeastern Aroostook County in which the degree of metamorphism increases from west to east. Vitrinite reflectance from the quarry'' plant fossil locality has a reflectance of 1.4%, which is slightly higher than the death line'' of oil and indicates a maximum paleotemperature of ca. 120--150 C. If not due to burial alone, this very low grade metamorphism may be due to (1) intrusion of nearby teschenite dikes or (2) the Maritime Disturbance of the Pennsylvanian. Based on conodont alteration indices and vitrinite and graptolite reflectance, the degree of thermal maturation of pre-Acadian Ordovician to Lower Devonian formations decreases rapidly several kilometers west of the prehnite-analcime isograd; the lowest rank rocks, in a northeast-trending ban from Square Lake to Mud Lake have paleotemperatures in the range of 60--90 C, the birth line'' of oil. In the post- orogenic Lower Devonian Trout Valley Formation immediately north of Mt. Katahdin, two samples about seven kilometers apart have anthracite grade reflectances of 3.0% and 8.2% respectively. Both localities are near andesite sills. Importantly, the smooth nongranular non-coked texture of these samples suggests that all or part of the Trout Valley Formation had been heated by an unidentified thermal event to temperatures above the coking range of coal before being subjected to later very local contact metamorphism by dikes and sills.

  20. Saturn, Approaching Northern Summer

    NASA Image and Video Library

    2016-09-15

    Since NASA's Cassini spacecraft arrived at Saturn in mid-2004, the planet's appearance has changed greatly. The shifting angle of sunlight as the seasons march forward has illuminated the giant hexagon-shaped jet stream around the north polar region, and the subtle bluish hues seen earlier in the mission have continued to fade. Earlier views obtained in 2004 and 2009 (see PIA06077 and PIA11667) demonstrate how drastically the illumination has changed. This view shows Saturn's northern hemisphere in 2016, as that part of the planet nears its northern hemisphere summer solstice in May 2017. Saturn's year is nearly 30 Earth years long, and during its long time there, Cassini has observed winter and spring in the north, and summer and fall in the south. The spacecraft will complete its mission just after northern summer solstice, having observed long-term changes in the planet's winds, temperatures, clouds and chemistry. Cassini scanned across the planet and its rings on April 25, 2016, capturing three sets of red, green and blue images to cover this entire scene showing the planet and the main rings. The images were obtained using Cassini's wide-angle camera at a distance of approximately 1.9 million miles (3 million kilometers) from Saturn and at an elevation of about 30 degrees above the ring plane. The view looks toward the sunlit side of the rings from a sun-Saturn-spacecraft angle, or phase angle, of 55 degrees. Image scale on Saturn is about 111 miles (178 kilometers) per pixel. The exposures used to make this mosaic were obtained just prior to the beginning of a 44-hour movie sequence. http://photojournal.jpl.nasa.gov/catalog/PIA21046

  1. Jupiter's Northern Lights

    NASA Image and Video Library

    2017-09-06

    This is a reconstructed view of Jupiter's northern lights through the filters of Juno's Ultraviolet Imaging Spectrometer (UVS) instrument on Dec. 11, 2016, as the Juno spacecraft approached Jupiter, passed over its poles, and plunged towards the equator. Such measurements present a real challenge for the spacecraft's science instruments: Juno flies over Jupiter's poles at 30 miles (50 kilometers) per second -- more than 100,000 miles per hour -- speeding past auroral forms in a matter of seconds. https://photojournal.jpl.nasa.gov/catalog/PIA21938

  2. Northern Summer on Titan

    NASA Image and Video Library

    2017-06-14

    NASA's Cassini spacecraft sees bright methane clouds drifting in the summer skies of Saturn's moon Titan, along with dark hydrocarbon lakes and seas clustered around the north pole. Compared to earlier in Cassini's mission, most of the surface in the moon's northern high latitudes is now illuminated by the sun. The image was taken with the Cassini spacecraft narrow-angle camera on June 9, 2017, using a spectral filter that preferentially admits wavelengths of near-infrared light centered at 938 nanometers. Cassini obtained the view at a distance of about 315,000 miles (507,000 kilometers) from Titan. https://photojournal.jpl.nasa.gov/catalog/PIA21615

  3. Fires in Northern Australia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Several fires were detected in Northern Australia by MODIS. The fires show up as red dots, superimposed on a surface reflectance product. The image also shows the Clarence Strait, which separates the mainland from Melville Island to the northwest and the smaller Bathurst Island to its west. The Strait connects the more confined, bowl-shaped Van Diemen Gulf to the Beagle Gulf. To the right of the image at the top is the Gulf of Carpentaria, which appears to be full of phytoplankton, as evidenced by the blue-green swirls in the waters

  4. A synchrotron-based local computed tomography combined with data-constrained modelling approach for quantitative analysis of anthracite coal microstructure

    PubMed Central

    Chen, Wen Hao; Yang, Sam Y. S.; Xiao, Ti Qiao; Mayo, Sherry C.; Wang, Yu Dan; Wang, Hai Peng

    2014-01-01

    Quantifying three-dimensional spatial distributions of pores and material compositions in samples is a key materials characterization challenge, particularly in samples where compositions are distributed across a range of length scales, and where such compositions have similar X-ray absorption properties, such as in coal. Consequently, obtaining detailed information within sub-regions of a multi-length-scale sample by conventional approaches may not provide the resolution and level of detail one might desire. Herein, an approach for quantitative high-definition determination of material compositions from X-ray local computed tomography combined with a data-constrained modelling method is proposed. The approach is capable of dramatically improving the spatial resolution and enabling finer details within a region of interest of a sample larger than the field of view to be revealed than by using conventional techniques. A coal sample containing distributions of porosity and several mineral compositions is employed to demonstrate the approach. The optimal experimental parameters are pre-analyzed. The quantitative results demonstrated that the approach can reveal significantly finer details of compositional distributions in the sample region of interest. The elevated spatial resolution is crucial for coal-bed methane reservoir evaluation and understanding the transformation of the minerals during coal processing. The method is generic and can be applied for three-dimensional compositional characterization of other materials. PMID:24763649

  5. A synchrotron-based local computed tomography combined with data-constrained modelling approach for quantitative analysis of anthracite coal microstructure.

    PubMed

    Chen, Wen Hao; Yang, Sam Y S; Xiao, Ti Qiao; Mayo, Sherry C; Wang, Yu Dan; Wang, Hai Peng

    2014-05-01

    Quantifying three-dimensional spatial distributions of pores and material compositions in samples is a key materials characterization challenge, particularly in samples where compositions are distributed across a range of length scales, and where such compositions have similar X-ray absorption properties, such as in coal. Consequently, obtaining detailed information within sub-regions of a multi-length-scale sample by conventional approaches may not provide the resolution and level of detail one might desire. Herein, an approach for quantitative high-definition determination of material compositions from X-ray local computed tomography combined with a data-constrained modelling method is proposed. The approach is capable of dramatically improving the spatial resolution and enabling finer details within a region of interest of a sample larger than the field of view to be revealed than by using conventional techniques. A coal sample containing distributions of porosity and several mineral compositions is employed to demonstrate the approach. The optimal experimental parameters are pre-analyzed. The quantitative results demonstrated that the approach can reveal significantly finer details of compositional distributions in the sample region of interest. The elevated spatial resolution is crucial for coal-bed methane reservoir evaluation and understanding the transformation of the minerals during coal processing. The method is generic and can be applied for three-dimensional compositional characterization of other materials.

  6. Expansive Northern Volcanic Plains

    NASA Image and Video Library

    2015-04-16

    Mercury northern region is dominated by expansive smooth plains, created by huge amounts of volcanic material flooding across Mercury surface in the past, as seen by NASA MESSENGER spacecraft. The volcanic lava flows buried craters, leaving only traces of their rims visible. Such craters are called ghost craters, and there are many visible in this image, including a large one near the center. Wrinkle ridges cross this scene and small troughs are visible regionally within ghost craters, formed as a result of the lava cooling. The northern plains are often described as smooth since their surface has fewer impact craters and thus has been less battered by such events. This indicates that these volcanic plains are younger than Mercury's rougher surfaces. Instrument: Mercury Dual Imaging System (MDIS) Center Latitude: 60.31° N Center Longitude: 36.87° E Scale: The large ghost crater at the center of the image is approximately 103 kilometers (64 miles) in diameter http://photojournal.jpl.nasa.gov/catalog/PIA19415

  7. Hubble Spots Northern Hemispheric Clouds on Uranus

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Using visible light, astronomers for the first time this century have detected clouds in the northern hemisphere of Uranus. The newest images, taken July 31 and Aug. 1, 1997 with NASA Hubble Space Telescope's Wide Field and Planetary Camera 2, show banded structure and multiple clouds. Using these images, Dr. Heidi Hammel (Massachusetts Institute of Technology) and colleagues Wes Lockwood (Lowell Observatory) and Kathy Rages (NASA Ames Research Center) plan to measure the wind speeds in the northern hemisphere for the first time.

    Uranus is sometimes called the 'sideways' planet, because its rotation axis tipped more than 90 degrees from the planet's orbit around the Sun. The 'year' on Uranus lasts 84 Earth years, which creates extremely long seasons - winter in the northern hemisphere has lasted for nearly 20 years. Uranus has also been called bland and boring, because no clouds have been detectable in ground-based images of the planet. Even to the cameras of the Voyager spacecraft in 1986, Uranus presented a nearly uniform blank disk, and discrete clouds were detectable only in the southern hemisphere. Voyager flew over the planet's cloud tops near the dead of northern winter (when the northern hemisphere was completely shrouded in darkness).

    Spring has finally come to the northern hemisphere of Uranus. The newest images, both the visible-wavelength ones described here and those taken a few days earlier with the Near Infrared and Multi-Object Spectrometer (NICMOS) by Erich Karkoschka (University of Arizona), show a planet with banded structure and detectable clouds.

    Two images are shown here. The 'aqua' image (on the left) is taken at 5,470 Angstroms, which is near the human eye's peak response to wavelength. Color has been added to the image to show what a person on a spacecraft near Uranus might see. Little structure is evident at this wavelength, though with image-processing techniques, a small cloud can be seen near the planet's northern limb

  8. Decomposition in northern Minnesota peatlands

    SciTech Connect

    Farrish, K.W.

    1985-01-01

    Decomposition in peatlands was investigated in northern Minnesota. Four sites, an ombrotrophic raised bog, an ombrotrophic perched bog and two groundwater minerotrophic fens, were studied. Decomposition rates of peat and paper were estimated using mass-loss techniques. Environmental and substrate factors that were most likely to be responsible for limiting decomposition were monitored. Laboratory incubation experiments complemented the field work. Mass-loss over one year in one of the bogs, ranged from 11 percent in the upper 10 cm of hummocks to 1 percent at 60 to 100 cm depth in hollows. Regression analysis of the data for that bog predicted no mass-loss below 87 cm. Decomposition estimates on an area basis were 2720 and 6460 km/ha yr for the two bogs; 17,000 and 5900 kg/ha yr for the two fens. Environmental factors found to limit decomposition in these peatlands were reducing/anaerobic conditions below the water table and cool peat temperatures. Substrate factors found to limit decomposition were low pH, high content of resistant organics such as lignin, and shortages of available N and K. Greater groundwater influence was found to favor decomposition through raising the pH and perhaps by introducing limited amounts of dissolved oxygen.

  9. Freshwater fishes of northern Australia.

    PubMed

    Pusey, Bradley J; Burrows, Damien W; Kennard, Mark J; Perna, Colton N; Unmack, Peter J; Allsop, Quentin; Hammer, Michael P

    2017-04-11

    Northern Australia is biologically diverse and of national and global conservation signicance. Its ancient landscape contains the world's largest area of savannah ecosystem in good ecological condition and its rivers are largely free-flowing. Agriculture, previously confined largely to open range-land grazing, is set to expand in extent and to focus much more on irrigated cropping and horticulture. Demands on the water resources of the region are thus, inevitably increasing. Reliable information is required to guide and inform development and help plan for a sustainable future for the region which includes healthy rivers that contain diverse fish assemblages. Based on a range of information sources, including the outcomes of recent and extensive new field surveys, this study maps the distribution of the 111 freshwater fishes (excluding elasmobranches) and 42 estuarine vagrants recorded from freshwater habitats of the region. We classify the habitat use and migratory biology of each species. This study provides a comprehensive assessment of the diversity and distribution of fishes of the region within a standardised nomenclatural framework. In addition, we summarise the outcomes of recent phylogeographic and phylogenetic research using molecular technologies to identify where issues of taxonomy may need further scrutiny. The study provides an informed basis for further research on the spatial arrangement of biodiversity and its relationship to environmental factors (e.g. hydrology), conservation planning and phylogentic variation within individual taxa.

  10. Mitigating Radicalism in Northern Nigeria

    DTIC Science & Technology

    2013-08-01

    radicalization in northern Nigeria. u Active engagement of youth and communities in peacebuilding programs that facilitate interactions among individuals...leaders, sustained development investments in marginalized communities , promotion of values of inclusivity to mitigate the spread of extremist ideology...claiming to have repelled Boko Haram, the militants return, regroup, and seek revenge. As a result, social and economic activities in the northern

  11. Report on Ontario's Northern Schools.

    ERIC Educational Resources Information Center

    2003

    Ontario's funding formula fails to recognize the unique needs of northern school boards, which cover immense geographic areas, have many small schools, and enroll a high proportion of Aboriginal students. This report examines school size, enrollment, and staffing in northern Ontario schools, drawing on 2002-03 tracking reports of provincial…

  12. Northern Sinus Meridiani Stereo

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-341, 25 April 2003

    This is a stereo (3-d anaglyph) composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle images of northern Sinus Meridiani near 2oN, 0oW. The light-toned materials at the south (bottom) end of the picture are considered to be thick (100-200 meters; 300-600 ft) exposures of sedimentary rock. Several ancient meteor impact craters are being exhumed from within these layered materials. To view in stereo, use '3-d' glasses with red over the left eye, and blue over the right. The picture covers an area approximately 113 km (70 mi) wide; north is up.

  13. Glyphosate in northern ecosystems.

    PubMed

    Helander, Marjo; Saloniemi, Irma; Saikkonen, Kari

    2012-10-01

    Glyphosate is the main nonselective, systemic herbicide used against a wide range of weeds. Its worldwide use has expanded because of extensive use of certain agricultural practices such as no-till cropping, and widespread application of glyphosate-resistant genetically modified crops. Glyphosate has a reputation of being nontoxic to animals and rapidly inactivated in soils. However, recent evidence has cast doubts on its safety. Glyphosate may be retained and transported in soils, and there may be cascading effects on nontarget organisms. These processes may be especially detrimental in northern ecosystems because they are characterized by long biologically inactive winters and short growing seasons. In this opinion article, we discuss the potential ecological, environmental and agricultural risks of intensive glyphosate use in boreal regions.

  14. Smoke Blankets Northern California

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Lightning strikes have sparked more than a thousand fires in northern California. This image was captured by the Multi-angle Imaging SpectroRadiometer's nadir (vertical-viewing) camera on 27 June 2008. Cape Mendocino is at the center of the image and Mt. Shasta is near the upper right. Concentrated smoke is visible in several river valleys and the large smoke cloud extends over the Pacific Ocean for hundreds of kilometers.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, D.C. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, Md. JPL is a division of the California Institute of Technology.

  15. Saturn Northern Hemisphere

    NASA Image and Video Library

    1998-12-05

    This false color picture of Saturn’s northern hemisphere was assembled from ultraviolet, violet and green images obtained Aug. 19 by Voyager 2 from a range of 7.1 million kilometers (4.4 million miles). The several weather patterns evident include three spots flowing westward at about 15 meters-per-second (33 mph). Although the cloud system associated with the western-most spot is part of this flow, the spot itself moves eastward at about 30 meters-per-second (65 mph). Their joint flow shows the anti-cyclonic rotation of the spot, which is about 3,000 km. (1,900 mi.) in diameter. The ribbon- like feature to the north marks a high-speed jet where wind speeds approach 150 meters-per-second (330 mph). http://photojournal.jpl.nasa.gov/catalog/PIA01365

  16. Northern Sinus Meridiani Stereo

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-341, 25 April 2003

    This is a stereo (3-d anaglyph) composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide angle images of northern Sinus Meridiani near 2oN, 0oW. The light-toned materials at the south (bottom) end of the picture are considered to be thick (100-200 meters; 300-600 ft) exposures of sedimentary rock. Several ancient meteor impact craters are being exhumed from within these layered materials. To view in stereo, use '3-d' glasses with red over the left eye, and blue over the right. The picture covers an area approximately 113 km (70 mi) wide; north is up.

  17. Relief history and denudation evolution of the northern Tibet margin: Constraints from 40Ar/39Ar and (U-Th)/He dating and implications for far-field effect of rising plateau

    NASA Astrophysics Data System (ADS)

    Wang, Fei; Feng, Huile; Shi, Wenbei; Zhang, Weibin; Wu, Lin; Yang, Liekun; Wang, Yinzhi; Zhang, Zhigang; Zhu, Rixiang

    2016-04-01

    How does the rising Tibetan Plateau affect its peripheral region? The current understanding of the mechanism of orogenic plateau development is incomplete and thus no consensus yet exists in this regard. However, our new 40Ar/39Ar and (U-Th)/He dataset presented in this study may shed some light on this issue. 40Ar/39Ar dating, on two vertical transects from the massif between Nuomuhong and Golmud, indicates that the Eastern Kunlun Range was built-up and exhumated during the later Triassic initially, and a minimum overburden of 11.7-14.0 km has been eroded since 220 Ma. (U-Th)/He age-elevation relationships (AERs) indicate a rapid exhumation event at 40 Ma following a long period of slow exhumation phase from late Mesozoic to early Eocene time. In this study, two scenarios - one assuming a single stage and the other assuming multiple stages of evolution history - are modeled. Modeling of a multiple stage scenario is reasonable and is able to reflect the "actual" situation, which reveals the entire denudation and relief history of the northern Tibet from late Mesozoic to the present time. After prolonged denudation before 50 Ma, a low topography ( 0.17 times the relief of the present) developed by 50 Ma with an erosion rate of 0.013-0.013+ 0.025 mm/yr. The highest relief ( 1.82 times the relief of the present) of the Cenozoic time came into being at 40 Ma with an erosion rate of 0.052 ± 0.025 mm/yr, which was possibly a result of the collision between India and Eurasia. Subsequently, the relief steadily decreased to the present level due to continued denudation. This suggests that deformation propagation from the continued convergence boundary between India and Eurasia was insignificant after the construction of the highest relief. This observation is broadly consistent with published accounts on the stratigraphic, cooling, and faulting histories of the northern Tibet margin.

  18. WIND VELOCITIES AND SAND FLUXES IN MESQUITE DUNE-LANDS IN THE NORTHERN CHIHUAHUAN DESERT: A COMPARISON BETWEEN FIELD MEASUREMENTS AND THE QUIC (QUICK URBAN AND INDUSTRIAL COMPLEX) MODEL

    EPA Science Inventory

    The poster shows comparisons of wind velocities and sand fluxes between field measurements and a computer model, called QUIC (Quick Urban & Industrial Complex). The comparisons were made for a small desert region in New Mexico.

  19. WIND VELOCITIES AND SAND FLUXES IN MESQUITE DUNE-LANDS IN THE NORTHERN CHIHUAHUAN DESERT: A COMPARISON BETWEEN FIELD MEASUREMENTS AND THE QUIC (QUICK URBAN AND INDUSTRIAL COMPLEX) MODEL

    EPA Science Inventory

    The poster shows comparisons of wind velocities and sand fluxes between field measurements and a computer model, called QUIC (Quick Urban & Industrial Complex). The comparisons were made for a small desert region in New Mexico.

  20. Bioactive compounds from northern plants.

    PubMed

    Hohtola, Anja

    2010-01-01

    various secondary metabolites. The most abundant, among these compounds, are the naphthoquinones. Bilberry (Vaccinium myrtillus) is a characteristic field layer species in boreal forests. Bilberry and other northern Vaccinium species, berries and leaves, contain high amounts of phenolic compounds. Bilberries are known for its exceptionally high amounts ofanthocyanins with powerful antioxidant capacity. They have been shown to possess beneficial health effects, like having a protective role in cardiovascular diseases and cancer. Many flavonoids also seem to have antiviral, antibacterial, antifungal and antiallergenic properties. The effect of ingested cranberry (V. oxycoccus) juice has been shown to prevent urinary tract infections in women.

  1. Fences and grazing management in northern Namibia

    NASA Astrophysics Data System (ADS)

    Prudat, Brice; Bloemertz, Lena; Kuhn, Nikolaus J.

    2016-04-01

    Since Namibian independence, many fences have been erected in the communal land of the Ohangwena region in northern Namibia. Most fencing issues discussed so far in the region concern large-scale fencing of communal land by the new Namibian elite. Rarely discussed are the fences erected around small-scale farmers' parcels. This paper will discuss the impact of such increased small-scale fencing activities in northern Namibia. Fencing of land has different functions, including protection of fields against livestock and securing property rights. However, not all community members can afford the monetary and labor costs involved. In the annual agricultural cycle of the study area, livestock is left un-herded after the harvest of most crops. They can then feed on available crop remains and grass on the fields. The livestock then freely utilizes unfenced and unprotected land. This system has the advantage to accelerate crop degradation and fertilize the soils. However, by erecting efficient fences, the new middle-class community members concentrate fertility in their own field, thereby degrading agricultural soils of poorer farmers. Potentially, such small-scale fencing of land has therefore an impact on sol quality and thus fosters degradation of unfenced cropland. By using fences as features to determine the limits of the new land rights, the ongoing Communal Land Reform may not only promote the erection of fences, but may also have a negative impact on soil quality and potentially food security of small-scale farmers without cattle.

  2. HUBBLE SPOTS NORTHERN HEMISPHERIC CLOUDS ON URANUS

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Using visible light, astronomers for the first time this century have detected clouds in the northern hemisphere of Uranus. The newest images, taken July 31 and Aug. 1, 1997 with NASA Hubble Space Telescope's Wide Field and Planetary Camera 2, show banded structure and multiple clouds. Using these images, Dr. Heidi Hammel (Massachusetts Institute of Technology) and colleagues Wes Lockwood (Lowell Observatory) and Kathy Rages (NASA Ames Research Center) plan to measure the wind speeds in the northern hemisphere for the first time. Uranus is sometimes called the 'sideways' planet, because its rotation axis is tipped more than 90 degrees from the planet's orbit around the Sun. The 'year' on Uranus lasts 84 Earth years, which creates extremely long seasons - winter in the northern hemisphere has lasted for nearly 20 years. Uranus has also been called bland and boring, because no clouds have been detectable in ground-based images of the planet. Even to the cameras of the Voyager spacecraft in 1986, Uranus presented a nearly uniform blank disk, and discrete clouds were detectable only in the southern hemisphere. Voyager flew over the planet's cloud tops near the dead of northern winter (when the northern hemisphere was completely shrouded in darkness). Spring has finally come to the northern hemisphere of Uranus. The newest images, both the visible-wavelength ones described here and those taken a few days earlier with the Near Infrared and Multi-Object Spectrometer (NICMOS) by Erich Karkoschka (University of Arizona), show a planet with banded structure and detectable clouds. Two images are shown here. The 'aqua' image (on the left) is taken at 5,470 Angstroms, which is near the human eye's peak response to wavelength. Color has been added to the image to show what a person on a spacecraft near Uranus might see. Little structure is evident at this wavelength, though with image-processing techniques, a small cloud can be seen near the planet's northern limb (rightmost

  3. Forest Fires in Russia and Northern China

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Smoke plumes from forest fires scattered along the border between the Russian Far East and northern China are clearly visible in this true-color image from the Sea-viewing Wide-Field-of-view Sensor (SeaWiFS) on June 16, 2000. Fires in Siberia occur every summer, and severe outbreaks occur every ten years or so, with the most recent in 1998. The fires are ignited by lightning, and are so remote that it is impossible to fight them effectively. Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  4. Forest Fires in Russia and Northern China

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Smoke plumes from forest fires scattered along the border between the Russian Far East and northern China are clearly visible in this true-color image from the Sea-viewing Wide-Field-of-view Sensor (SeaWiFS) on June 16, 2000. Fires in Siberia occur every summer, and severe outbreaks occur every ten years or so, with the most recent in 1998. The fires are ignited by lightning, and are so remote that it is impossible to fight them effectively. Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  5. Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America

    USDA-ARS?s Scientific Manuscript database

    The book “Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America” summarizes published research in soil science and agronomy from various field experiments conducted in the soil-climatic/agro-ecological regions of the Northern Great Plains of North America....

  6. 8. Another environmental view, from the northern bridge approach looking ...

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

    8. Another environmental view, from the northern bridge approach looking south along 74th Place, through the roadbed. Grain fields which have been harvested can be seen in the background. The bridge's characteristic profile and balustrade are prominent. - Vigo County Bridge No. 139, Spanning Sugar Creek at Seventy-fourth Place, Terre Haute, Vigo County, IN

  7. Mechanized thinning of northern hardwood pole stands: methods and economics.

    Treesearch

    Frank E. Biltonen; Wiliam A. Hillstrom; Helmuth M. Steinhilb; Richard M. Godman

    1976-01-01

    Describes a study of various thinning treatments in northern hardwood pole stands, using mechanized felling, skidding, and field chipping, as well as chain saw felling. Cost analyses showed that a profit can be made although it is less than can be made with clearcutting.

  8. Forest habitat types of northern Idaho: A second approximation

    Treesearch

    Stephen V. Cooper; Kenneth E. Neiman; David W. Roberts

    1991-01-01

    The addition of more than 900 plots to the Daubenmire's original 181-plot database has resulted in a refinement of their potential natural vegetation-based land classification for northern Idaho. A diagnostic, indicator species-based key is provided for field identification of the eight climax series, 46 habitat types, and 60 phases. Recognized syntaxa are...

  9. Tree-section harvesting of northern hardwood thinnings.

    Treesearch

    James A. Mattson

    1993-01-01

    Describes the results of a field trial of tree-section harvesting, a shortwood version of whole-tree harvesting, in a northern hardwood thinning. This technique is technically feasible and especially useful where the appearance of the residual stand is a primary concern.

  10. Pollination biology of northern red and black oak

    Treesearch

    Robert A. Cecich; William W. Haenchen

    1995-01-01

    Pistillate flower abortion in northern red oak and black oak was evaluated in relation to pollination and fertilization. The presence, position, and characteristics of the pollen grains, pollen tubes, and ovules were determined with bright field and fluorescence microscopy. Flower survival counts were made weekly, from late April to mid- September. Both species have...

  11. Forest statistics for the Northern Piedmont of Virginia, 1992

    Treesearch

    Michael T. Thompson

    1992-01-01

    This report highlights the principal findings of the sixth forest survey of the Northern Piedmont of Virginia. Field work began in June 1991 and was completed in September 1991. Five previous surveys, completed in 1940, 1957, 1965, 1976, and 1986, provide statistics for measuring changes and trends over the past 52 years. The primary emphasis in this report is on the...

  12. Forest statistics for the Northern Mountains of Virginia, 1992

    Treesearch

    Tony G. Johnson

    1992-01-01

    This report highlights the principal findings of the sixth forest survey of the Northern Mountains of Virginia. Field work began in September 1991 and was completed in November 1991. Five previous surveys, completed in 1940, 1957, 1966, 1977, and 1986, provide statistics for measuring changes and trends over the past 52 years. The primary emphasis in this report is on...

  13. Snow in northern Alaska

    NASA Image and Video Library

    2017-09-28

    As autumn colors moved across much of the lower forty-eight states in mid-October 2015, winter weather had already arrived in Alaska. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image of the icy scene on October 16 as it passed over the region. Point Barrow, the northern-most location in the United States sits between the Chukchi Sea (west) and the Beaufort Sea on the east. The rugged peaks of the Brooks Range can be seen along the southern section of the image. North of the Brooks Range the land is almost entirely covered with snow; to the south the tan and browns visible between snow marks uncovered land. Sea ice lies over the waters near the coasts of much of Alaska’s North Slope, especially east of Point Barrow. White cloud banks are notable in the northeast and southeast sections of the image. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  14. Estimating cull in northern hardwoods

    Treesearch

    W.M. Zillgitt; S.R. Gevorkiantz

    1946-01-01

    Cull in northern hardwood stands is often very heavy and is difficult to estimate. To help clarify this situation and aid the average cruiser to become more accurate in his estimates, the study reported here should prove very helpful.

  15. The interaction of a magnetic cloud with the Earth - Ionospheric convection in the Northern and Southern Hemispheres for a wide range of quasi-steady interplanetary magnetic field conditions

    NASA Technical Reports Server (NTRS)

    Freeman, M. P.; Farrugia, C. J.; Burlaga, L. F.; Hairston, M. R.; Greenspan, M. E.; Ruohoniemi, J. M.; Lepping, R. P.

    1993-01-01

    Observations are presented of the ionospheric convection in cross sections of the polar cap and auroral zone as part of the study of the interaction of the Earth's magnetosphere with the magnetic cloud of January 13-15, 1988. For strongly northward IMF, the convection in the Southern Hemisphere is characterized by a two-cell convection pattern comfined to high latitudes with sunward flow over the pole. The strength of the flows is comparable to that later seen under southward IMF. Superimposed on this convection pattern there are clear dawn-dusk asymmetries associated with a one-cell convection component whose sense depends on the polarity of the magnetic cloud's large east-west magnetic field component. When the cloud's magnetic field turns southward, the convection is characterized by a two-cell pattern extending to lower latitude with antisunward flow over the pole. There is no evident interhemispheric difference in the structure and strength of the convection. Superimposed dawn-dusk asymmetries in the flow patterns are observed which are only in part attributable to the east-west component of the magnetic field.

  16. Turbulent times in the northern polar ionosphere?

    NASA Astrophysics Data System (ADS)

    Burston, Robert; Astin, Ivan; Mitchell, Cathryn; Alfonsi, Lucilla; Pedersen, Todd; Skone, Susan

    2010-04-01

    A model is presented of the growth rate of turbulently generated irregularities in the electron concentration of northern polar cap plasma patches. The turbulence is generated by the short-term fluctuations in the electric field imposed on the polar cap ionosphere by electric field mapping from the magnetosphere. The model uses an ionospheric imaging algorithm to specify the state of the ionosphere throughout. The growth rates are used to estimate mean amplitudes for the irregularities, and these mean amplitudes are compared with observations of the scintillation indices S4 and σ$\\phi$ by calculating the linear correlation coefficients between them. The scintillation data are recorded by GPS L1 band receivers stationed at high northern latitudes. A total of 13 days are analyzed, covering four separate magnetic storm periods. These results are compared with those from a similar model of the gradient drift instability (GDI) growth rate. Overall, the results show better correlation between the GDI process and the scintillation indices than for the turbulence process and the scintillation indices. Two storms, however, show approximately equally good correlations for both processes, indicating that there might be times when the turbulence process of irregularity formation on plasma patches may be the controlling one.

  17. MISR Views Northern Australia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    MISR images of tropical northern Australia acquired on June 1, 2000 (Terra orbit 2413) during the long dry season. Left: color composite of vertical (nadir) camera blue, green, and red band data. Right: multi-angle composite of red band data only from the cameras viewing 60 degrees aft, 60 degrees forward, and nadir. Color and contrast have been enhanced to accentuate subtle details. In the left image, color variations indicate how different parts of the scene reflect light differently at blue, green, and red wavelengths; in the right image color variations show how these same scene elements reflect light differently at different angles of view. Water appears in blue shades in the right image, for example, because glitter makes the water look brighter at the aft camera's view angle. The prominent inland water body is Lake Argyle, the largest human-made lake in Australia, which supplies water for the Ord River Irrigation Area and the town of Kununurra (pop. 6500) just to the north. At the top is the southern edge of Joseph Bonaparte Gulf; the major inlet at the left is Cambridge Gulf, the location of the town of Wyndham (pop. 850), the port for this region. This area is sparsely populated, and is known for its remote, spectacular mountains and gorges. Visible along much of the coastline are intertidal mudflats of mangroves and low shrubs; to the south the terrain is covered by open woodland merging into open grassland in the lower half of the pictures.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

  18. MISR Views Northern Australia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    MISR images of tropical northern Australia acquired on June 1, 2000 (Terra orbit 2413) during the long dry season. Left: color composite of vertical (nadir) camera blue, green, and red band data. Right: multi-angle composite of red band data only from the cameras viewing 60 degrees aft, 60 degrees forward, and nadir. Color and contrast have been enhanced to accentuate subtle details. In the left image, color variations indicate how different parts of the scene reflect light differently at blue, green, and red wavelengths; in the right image color variations show how these same scene elements reflect light differently at different angles of view. Water appears in blue shades in the right image, for example, because glitter makes the water look brighter at the aft camera's view angle. The prominent inland water body is Lake Argyle, the largest human-made lake in Australia, which supplies water for the Ord River Irrigation Area and the town of Kununurra (pop. 6500) just to the north. At the top is the southern edge of Joseph Bonaparte Gulf; the major inlet at the left is Cambridge Gulf, the location of the town of Wyndham (pop. 850), the port for this region. This area is sparsely populated, and is known for its remote, spectacular mountains and gorges. Visible along much of the coastline are intertidal mudflats of mangroves and low shrubs; to the south the terrain is covered by open woodland merging into open grassland in the lower half of the pictures.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

  19. Tornadoes Strike Northern Wisconsin

    NASA Technical Reports Server (NTRS)

    2007-01-01

    A series of tornadoes ripped through the Upper Midwest region of the United States in the evening of June 7, 2007. At least five different tornadoes touched down in Wisconsin, according to the Associated Press, one of which tore through the Bear Paw Resort in northern Wisconsin. Despite dropping as much as fifteen centimeters (six inches) of rain in some places and baseball-size hail in others, authorities were reporting no deaths attributable to the storm system, and only a smattering of injuries, but considerable property damage in some areas. When the MODIS instrument on NASA's Terra satellite observed the area on June 9, 2007, the track torn through the woods by one of the tornadoes stands out quite clearly. This photo-like image uses data collected by MODIS in the normal human vision range to give a familiar natural-looking appearance. The landscape is largely a checkerboard of farms, towns, roads, and cities. The pale land is predominantly farmland where crops have not fully grown in yet. Dark blue shows the winding path of rivers and lakes dotting the landscape. The large blue lake on the east (right) side of the image is Lake Michigan. Towns and cities, including the city of Green Bay, are gray. To the north side, farmland gives way to dark green as land use shifts from agriculture to the Menominee Indian Reservation and Nicolet National Forest. The diagonal slash through the dark green forested land shows the tornado track. Bare land was revealed where the tornado tore down trees or stripped vegetation off the branches. The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions.

  20. Tornadoes Strike Northern Wisconsin

    NASA Technical Reports Server (NTRS)

    2007-01-01

    A series of tornadoes ripped through the Upper Midwest region of the United States in the evening of June 7, 2007. At least five different tornadoes touched down in Wisconsin, according to the Associated Press, one of which tore through the Bear Paw Resort in northern Wisconsin. Despite dropping as much as fifteen centimeters (six inches) of rain in some places and baseball-size hail in others, authorities were reporting no deaths attributable to the storm system, and only a smattering of injuries, but considerable property damage in some areas. When the MODIS instrument on NASA's Terra satellite observed the area on June 9, 2007, the track torn through the woods by one of the tornadoes stands out quite clearly. This photo-like image uses data collected by MODIS in the normal human vision range to give a familiar natural-looking appearance. The landscape is largely a checkerboard of farms, towns, roads, and cities. The pale land is predominantly farmland where crops have not fully grown in yet. Dark blue shows the winding path of rivers and lakes dotting the landscape. The large blue lake on the east (right) side of the image is Lake Michigan. Towns and cities, including the city of Green Bay, are gray. To the north side, farmland gives way to dark green as land use shifts from agriculture to the Menominee Indian Reservation and Nicolet National Forest. The diagonal slash through the dark green forested land shows the tornado track. Bare land was revealed where the tornado tore down trees or stripped vegetation off the branches. The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions.

  1. Regional orientation of tectonic stress and the stress expressed by post-subduction high-magnesium volcanism in northern Baja California, Mexico: Tectonics and volcanism of San Borja volcanic field

    NASA Astrophysics Data System (ADS)

    Negrete-Aranda, Raquel; Cañón-Tapia, Edgardo; Brandle, Jose Luis; Ortega-Rivera, M. Amabel; Lee, James K. W.; Spelz, Ronald M.; Hinojosa-Corona, Alejandro

    2010-04-01

    Because of its long-lived (Late Miocene to Pleistocene) post-subduction volcanic activity and location, the San Borja volcanic field (SBVF) is a key area for understanding the physical mechanisms controlling the spatial distribution of post-subduction volcanism on the Peninsula of Baja California. In this paper, we study the distribution and general characteristics of individual eruptive centers in the SBVF, aiming to provide insight into the changing physical nature of post-subduction magmatism and the control on vent location in a very unique tectonic setting. Volcanic activity has built more than 227 high-magnesium andesites (HMA) monogenetic scoria cones and thick lava flows capping large mesas during the last 12.5 Ma. The average (mean) eruptive center in the SBVF has a height of 85 m, a basal diameter of 452 m and a slope angle of 30°. Our volcanic alignment analysis of this field is based on field data, satellite images, and a quantitative method for detecting volcanic center alignments. The morphologic data, together with new 40Ar/ 39Ar geochronology data have been used to refine our alignment analysis and to better delineate the temporal evolution of post-subduction volcanic activity in this field. The available ages vary from 3.53 ± 0.18 to 10 ± 0.23 Ma suggesting that the long-lived HMA volcanism occurred almost continuously (with some concentration of pulses) throughout Late Miocene and extending to the Pleistocene and even into the Quaternary, replacing the arc-related activity of the Comondú arc which vanished in this area around 12.5 Ma. Alignment analysis confirms a NW-SE direction as the preferred orientation of volcanic alignments and shows that vent elongations do not display a strong parallelism in any particular direction, marking the absence of matches between lineaments defined by multiple vents and orientations of vent elongation. The results of the volcanic alignment analysis allowed us to infer the direction of the maximum

  2. Factors favouring large organic production in the northern Adriatic: towards the northern Adriatic empirical ecological model

    NASA Astrophysics Data System (ADS)

    Kraus, R.; Supić, N.; Precali, R.

    2015-06-01

    Influenced by one of the largest Mediterranean rivers, Po, the northern Adriatic production is highly variable seasonally and interannually. The changes are especially pronounced between winters and seemingly reflect on total Adriatic bioproduction of certain species (anchovy). We analysed the long-term changes in the phytoplankton production at the transect in the region, as derived from monthly oceanographic cruises, in relation to concomitant geostrophic currents distribution in the area and in the Po River discharge rates in days preceding the cruises. In winter and early spring the phyto-abundances depended on existing circulation fields, in summer and autumn they were related to 1-15 days earlier Po River discharge rates and on concomitant circulation fields, while in late spring phyto-abundances increased 1-3 days after high Po River discharge rates regardless of circulation fields. During the entire year the phyto-abundances were dependant on forcing of the previous 1-12 months of surface fluxes and/or Po River rates. Large February blooms are, as well as February circulation patterns, precondited by low evaporation rates in previous November. From 1990 to 2004 a shift towards large winter bioproduction induced by circulation changes appeared. Performed investigations represent the preliminary actions in building of an empirical ecological model of the northern Adriatic which can be used in the sustainable economy of the region, however also in validation of the numerical ecological model of the region, which is currently being developed.

  3. Planetary period oscillations in Saturn's magnetosphere: Coalescence and reversal of northern and southern periods in late northern spring

    NASA Astrophysics Data System (ADS)

    Provan, G.; Cowley, S. W. H.; Lamy, L.; Bunce, E. J.; Hunt, G. J.; Zarka, P.; Dougherty, M. K.

    2016-10-01

    We investigate planetary period oscillations (PPOs) in Saturn's magnetosphere using Cassini magnetic field and Saturn kilometric radiation (SKR) data over the interval from late 2012 to the end of 2015, beginning 3 years after vernal equinox and ending 1.5 years before northern solstice. Previous studies have shown that the northern and southern PPO periods converged across equinox from southern summer values 10.8 h for the southern system and 10.6 h for the northern system and near coalesced 1 year after equinox, before separating again with the southern period 10.69 h remaining longer than the northern 10.64 h. We show that these conditions ended in mid-2013 when the two periods coalesced at 10.66 h and remained so until mid-2014, increasing together to longer periods 10.70 h. During coalescence the two systems were locked near magnetic antiphase with SKR modulations in phase, a condition in which the effects of the generating rotating twin vortex flows in the two ionospheres reinforce each other via hemisphere-to-hemisphere coupling. The magnetic-SKR relative phasing indicates the dominance of postdawn SKR sources in both hemispheres, as was generally the case during the study interval. In mid-2014 the two periods separated again, the northern increasing to 10.78 h by the end of 2015, similar to the southern period during southern summer, while the southern period remained fixed near 10.70 h, well above the northern period during southern summer. Despite this difference, this behavior resulted in the first enduring reversal of the two periods, northern longer than southern, during the Cassini era.

  4. Models, data available, and data requirements for estimating the effects of injecting saltwater into disposal wells in the greater Altamont-Bluebell oil and gas field, northern Uinta Basin, Utah

    USGS Publications Warehouse

    Freethey, Geoffrey W.

    1988-01-01

    Permits for disposing of salty oil-production water have been issued for 19 wells in the Greater Altamont-Bluebell field. During 1986 more than 500 million gallons of production water were injected into the Duchesne River, Uinta, and Green River Formations through 18 of these wells. The physical and chemical effects of injecting this water into aquifers containing potable water are poorly understood. Interfingering and the structural configuration of these formations add complexity to the description of the geometry and hydrogeology of the ground-water system.A preliminary assessment of the problem indicates that numerical modeling may offer a method of determining the effects of injection. Modeling possibilities include variable-density, three-dimensional flow, sectionaltransport, and areal-transport models. Data needed to develop these models can be derived from a synthesis of geologic, hydrologic, and hydrochemical data already available in the files of State and Federal agencies, oil companies, and private companies. Results from each modeling phase would contribute information for implementing the following phase. The result will be a better understanding of how water moves naturally through the groundwater system, the extent of alterations of both vertical and horizontal flow near the disposal wells, and an overall concept of the effects of deep injection on near-surface aquifers.

  5. Gaspé Belt subsurface geometry in the northern Québec Appalachians as revealed by an integrated geophysical and geological study: 2 — Seismic interpretation and potential field modelling results

    NASA Astrophysics Data System (ADS)

    Pinet, Nicolas

    2013-03-01

    Geological information, seismic reflection profiles and potential field data are used to study the geometry of the Middle Paleozoic Gaspé Belt (eastern Canada) that has been interpreted in various ways in the past. On the western edge of the Gaspé Belt, in the Matapédia area, growth strata are imaged on seismic profiles and testify of normal (or transtensional) motion during the period spanning the Silurian (and possibly Late Ordovician) to earliest Devonian along several faults, including the Shickshock-Sud Fault. In this area, Acadian deformation during the Middle to Late Devonian is associated with relatively modest shortening (less than 20%) accommodated by broad open folds, steeply-dipping neo-formed faults and inversion of previously formed faults. Neo-formed faults cut the entire Middle Paleozoic succession and offset the Ordovician Taconian unconformity suggesting that no sedimentary interval acted as an efficient décollement level. Toward the SE, the Sainte-Florence Fault divides rock assemblages with different paleogeographic settings and structural styles. Increase in tectonic complexity and amount of shortening to the south of the fault is interpreted as resulting of a vise effect between two basement blocks.

  6. Provenance of Norphlet sandstone, northern Gulf Coast

    SciTech Connect

    Ryan, W.P.; Ward, W.C.; Kuglar, R.L.

    1987-09-01

    The Upper Jurassic Norphlet sandstone of the northern Gulf Coast is predominantly subarkose, with some arkose in the eastern area and sublitharenite and quartzarenite in the western area. Despite great depths of burial and despite feldspar and rock-fragment constituents, diagenesis has not appreciably altered the composition of Norphlet sandstone. Therefore, reconstruction of original composition of Norphlet sandstone presented little difficulty. Variation in detrital modes of the Norphlet suggests compositionally distinct source terranes. Samples from Florida, Alabama, and Mississippi reflect the influence of metamorphic and plutonic rocks of the Appalachian Piedmont Province and of Triassic-Jurassic volcanic rocks. Sandstones in east Texas, northern Louisiana, and southern Arkansas were derived from sedimentary and metasedimentary rocks of the Ouachita system. The Arbuckle Mountains and Llano uplift may have supplied trace amounts of quartzo-feldspathic and volcanic-rock fragments to the extreme western part of the study area. Norphlet sandstones represent a mixture of collision-orogen-derived sediment from the Appalachian and/or Ouachita system and continental-block-derived sediment from paleohighs and uplifts within the Gulf basin. However, Norphlet sandstones plot in the craton-interior and transitional-continental fields on Q-F-L and QM-F-Lt tectonic-provenance diagrams, because of mineralogically mature source rocks, elimination of unstable grains by abrasion and sorting during deposition, and/or sediment mixing from different source terranes.

  7. Titan's Stratospheric Condensibles at High Northern Latitudes During Northern Winter

    NASA Technical Reports Server (NTRS)

    Anderson, Carrie; Samuelson, R.; Achterberg, R.

    2012-01-01

    The Infrared Interferometer Spectrometer (IRIS) instrument on board Voyager 1 caught the first glimpse of an unidentified particulate feature in Titan's stratosphere that spectrally peaks at 221 per centimeter. Until recently, this feature that we have termed 'the haystack,' has been seen persistently at high northern latitudes with the Composite Infrared Spectrometer (CIRS) instrument onboard Cassini, The strength of the haystack emission feature diminishes rapidly with season, becoming drastically reduced at high northern latitudes, as Titan transitions from northern winter into spring, In contrast to IRIS whose shortest wavenumber was 200 per centimeter, CIRS extends down to 10 per centimeter, thus revealing an entirely unexplored spectral region in which nitrile ices have numerous broad lattice vibration features, Unlike the haystack, which is only found at high northern latitudes during northern winter/early northern spring, this geometrically thin nitrile cloud pervades Titan's lower stratosphere, spectrally peaking at 160 per centimeter, and is almost global in extent spanning latitudes 85 N to 600 S, The inference of nitrile ices are consistent with the highly restricted altitude ranges over which these features are observed, and appear to be dominated by a mixture of HCN and HC3N, The narrow range in altitude over which the nitrile ices extend is unlike the haystack, whose vertical distribution is significantly broader, spanning roughly 70 kilometers in altitude in Titan's lower stratosphere, The nitrile clouds that CIRS observes are located in a dynamically stable region of Titan's atmosphere, whereas CH4 clouds, which ordinarily form in the troposphere, form in a more dynamically unstable region, where convective cloud systems tend to occur. In the unusual situation where Titan's tropopause cools significantly from the HASI 70.5K temperature minimum, CH4 should condense in Titan's lower stratosphere, just like the aforementioned nitrile clouds, although

  8. Titan's stratospheric condensibles at high northern latitudes during northern winter

    NASA Astrophysics Data System (ADS)

    Anderson, C.; Samuelson, R.; Achterberg, R.

    2012-04-01

    The Infrared Interferometer Spectrometer (IRIS) instrument on board Voyager 1 caught the first glimpse of an unidentified particulate feature in Titan’s stratosphere that spectrally peaks at 221 cm-1. Until recently, this feature that we have termed ‘the haystack,’ has been seen persistently at high northern latitudes with the Composite Infrared Spectrometer (CIRS) instrument onboard Cassini. The strength of the haystack emission feature diminishes rapidly with season, becoming drastically reduced at high northern latitudes, as Titan transitions from northern winter into spring. In contrast to IRIS whose shortest wavenumber was 200 cm-1, CIRS extends down to 10 cm-1, thus revealing an entirely unexplored spectral region in which nitrile ices have numerous broad lattice vibration features. Unlike the haystack, which is only found at high northern latitudes during northern winter/early northern spring, this geometrically thin nitrile cloud pervades Titan’s lower stratosphere, spectrally peaking at 160 cm-1, and is almost global in extent spanning latitudes 85°N to 60°S. The inference of nitrile ices are consistent with the highly restricted altitude ranges over which these features are observed, and appear to be dominated by a mixture of HCN and HC3N. The narrow range in altitude over which the nitrile ices extend is unlike the haystack, whose vertical distribution is significantly broader, spanning roughly 70 km in altitude in Titan’s lower stratosphere. The nitrile clouds that CIRS observes are located in a dynamically stable region of Titan’s atmosphere, whereas CH4 clouds, which ordinarily form in the troposphere, form in a more dynamically unstable region, where convective cloud systems tend to occur. In the unusual situation where Titan’s tropopause cools significantly from the HASI 70.5K temperature minimum, CH4 should condense in Titan’s lower stratosphere, just like the aforementioned nitrile clouds, although in significantly larger

  9. First oilfields of the Central and Northern North Sea

    SciTech Connect

    Swarbrick, R.E. ); Martin, J.A. )

    1991-03-01

    Only 25 years ago the areas now termed the Central and Northern North Sea were the true frontier exploration basins. Stratigraphy and structure were essentially unknown, except inferences drawn from the Mesozoic outcrops of Britain and Denmark. At that time the majority of small British onshore oil fields were reservoired in Paleozoic strata. In the Central North Sea, oil was first discovered in Paleocene deep-water sandstone and Upper Cretaceous chalk reservoirs. The first commercial reserves were proven with the discovery of the Ekofisk field (Upper Cretaceous) in 1969 and Forties field (Paleocene) in 1970, both now classed as giants. Subsequently stratigraphically deeper reservoirs were established, including Jurassic sandstones (Piper field) and Permian carbonates and sandstones (Auk and Argyll fields). Diversity of trap type and reservoir age is now a hallmark of the Central North Sea basin. In the Northern North Sea, the first exploration well in 1971 on the Brent field structure, a true wildcat whose nearest UK well control was 320 mi to the south, found oil in Middle Jurassic deltaic sandstones. A spate of discoveries on similar tilted fault blocks with Middle Jurassic and underlying Triassic alluvial-fluvial sandstone targets followed. Later, Upper Jurassic deep-water sandstones became established as a further significant reservoir with the Brae field and Magnus field discoveries. Original seismic data, well prognoses, and structure maps tell the story of these early discoveries. Public response in Norway and the UK to the emergence of the North Sea oil province on their doorstep will be reviewed.

  10. "Subtractive" Bilingualism in Northern Belize.

    ERIC Educational Resources Information Center

    Rubinstein, Robert A.

    "Subtractive" bilingualism in Northern Belize is analyzed based on an extension of a model by Wallace Lambert. The impact of English language instruction on Spanish speaking children in Corozal Town, the northernmost urban center in the British colony of Belize, Central America, is described. This description extends an earlier account…

  11. The outlook for northern forests

    Treesearch

    Stephen R. Shifley; W. Keith Moser; Sherri Wormstead; Francisco X. Aguilar

    2016-01-01

    The forests of the Northern United States have been remarkably resilient to nearly four centuries of immigration and settlement with associated anthropogenic disturbances caused by farming, logging, burning, urbanization, trade, and many other factors. Although resilient, forests conditions have been significantly impacted by humans as is illustrated by the extent of...

  12. Primary Science in Northern Ireland

    ERIC Educational Resources Information Center

    McAllister, Peter

    2005-01-01

    Since 1990 the science curriculum in Northern Ireland has gone through three major changes. In the beginning, fifteen attainment targets were introduced to an unsuspecting and largely unprepared teaching population: these were eventually reduced to five in 1993 and then to the present two in 1996. Unlike in England, technology has never stood as…

  13. BARRIERS TO NORTHERN SCHOOL DESEGREGATION.

    ERIC Educational Resources Information Center

    DENTLER, ROBERT A.

    UNLESS THE RATE OF INTEGRATION IN NORTHERN SCHOOLS IN LARGE CITIES ACCELERATES, THERE WILL BE EXTENSIVE URBAN SEGREGATION UNTIL AT LEAST THE MID-21ST CENTURY. HOWEVER, DATA FROM SMALLER CITIES SHOW THAT THERE SEEM TO BE "UNIFORM" CONDITIONS WHICH FAVOR DESEGREGATION--NEGRO PROTEST ACTION, STIMULUS FROM EXTRA-LOCAL AUTHORITY, AND A LESS HIGHLY…

  14. NUMA: A Northern Paiute History.

    ERIC Educational Resources Information Center

    Inter-Tribal Council of Nevada, Reno.

    One in a series of four histories of native Nevadans, this volume presents the story of the Northern Paiute people, or Numa, who lived, hunted, and travelled in the Great Basin area which occupies one-third of present day Nevada and parts of Oregon, Idaho, and California. Based on interviews with tribal elders and research conducted at numerous…

  15. Vesta Partly Shadowed Northern Regions

    NASA Image and Video Library

    2012-06-01

    This image from NASA Dawn spacecraft shows a part of asteroid Vesta surface reasonably far north into the northern hemisphere which appears washed out because it has been stretched to make features visible that would otherwise be too dark to see.

  16. Northern Storm in Full Force

    NASA Image and Video Library

    2013-01-31

    This mosaic of images from NASA Cassini spacecraft shows the trail of a great northern storm on Saturn raging in full force. The contrast in the images has been enhanced to make the turbulent parts of the storm in white stand out.

  17. Motivating Learners in Northern Communities.

    ERIC Educational Resources Information Center

    Swanson, Sharon

    2003-01-01

    A teacher at a northern Ontario adult Native literacy program describes how she cultivates student motivation. The teacher-student relationship is the most influential factor for motivating students. By focusing on cultural awareness, cultural teaching practices, and a sense of community, teachers can help students be successful. Program…

  18. Northern Border Pipeline Company NPDES Permit

    EPA Pesticide Factsheets

    Under NPDES permit MT-0030791, the Northern Border Pipeline Company is authorized to discharge from locations along the Northern Border Gas Transmission Pipeline located within the exterior boundaries of the Fort Peck Indian Reservation, Montana.

  19. Hydrocarbon Induced Seismicity in Northern Netherlands

    NASA Astrophysics Data System (ADS)

    Dost, B.; Spetzler, J.; Kraaijpoel, D.; Caccavale, M.

    2015-12-01

    The northern Netherlands has been regarded aseismic until the first earthquakes started in 1986, after more than 25 years of gas production from the one of the largest on-shore gas-fields in the World, the Groningen field, and accompanying smaller gas fields. Due to the shallow sources, at approximately 3 km depth, even small magnitude events cause considerable damage to buildings in the region. Since the largest recorded event in the Groningen field in 2012 with ML= 3,6, more than 30.000 damage claims were received by the mining company. Since 1995 a seismic monitoring network is operational in the region, consisting of 8 200m deep boreholes with 4 levels of 3C 4,5 Hz geophones. The network was designed for a location threshold of ML=1,5 over a 40x 80 km region. Average station separation was 20 km. At the end of 2014, 245 events have been recorded with ML ≥ 1,5, out of a total of 1100. Since 2003 a new mining law is in place in the Netherlands, which requires for each gas field in production a seismic risk analysis. Initially, due to the small number of events for specific fields, a general hazard (PSHA) was calculated for all gas-fields and a maximum magnitude was estimated at ML = 3,9. Since 2003 an increase in the activity rate is observed for the Groningen field, leading to the development of new models and a re-assessment of parameters like the maximum magnitude. More recently these models are extended to seismic risk, where also the fragility of the regional buildings is taken into account. Understanding the earthquake process is essential in taking mitigation measures. Continued research is focused on reducing the uncertainties in the hazard and risk models and is accompanied by an upgrade of the monitoring network. In 2014 a new dense network was designed to monitor the Groningen gas field in this region (30*40 km) with an average separation of 4 km. This allows an improved location threshold (M>0,5) and location accuracy (50-100m). A detailed P- and S

  20. Imaging Lithospheric-scale Structure Beneath Northern Altiplano in Southern Peru and Northern Bolivia

    NASA Astrophysics Data System (ADS)

    Kumar, A.; Wagner, L. S.; Beck, S. L.; Zandt, G.; Long, M. D.

    2014-12-01

    The northern Altiplano plateau of southern Peru and northern Bolivia is one of the highest topographic features on the Earth, flanked by Western and Eastern Cordillera along its margin. It has strongly influenced the local and far field lithospheric deformation since the early Miocene (Masek et al., 1994). Previous studies have emphasized the importance of both the crust and upper mantle in the evolution of Altiplano plateau (McQuarrie et al., 2005). Early tomographic and receiver function studies, south of 16° S, show significant variations in the crust and upper mantle properties in both perpendicular and along strike direction of the Altiplano plateau (Dorbath et. al., 1993; Myers et al., 1998; Beck and Zandt, 2002). In order to investigate the nature of subsurface lithospheric structure below the northern Altiplano, between 15-18° S, we have determined three-dimensional seismic tomography models for Vp and Vs using P and S-wave travel time data from two recently deployed local seismic networks of CAUGHT and PULSE. We also used data from 8 stations from the PERUSE network (PERU Subduction Experiment). Our preliminary tomographic models show a complex variation in the upper mantle velocity structure with depth, northwest and southeast of lake Titicaca. We see the following trend, at ~85 km depth, northwest of lake Titicaca: low Vp and Vs beneath the Western Cordillera, high Vs beneath the Altiplano and low Vp and Vs beneath the Eastern Cordillera. This low velocity anomaly, beneath Eastern Cordillera, seems to coincide with Kimsachata, a Holocene volcano in southern Peru. At depth greater than ~85 km: we find high velocity anomaly beneath the Western Cordillera and low Vs beneath the Altiplano. This high velocity anomaly, beneath Western Cordillera, coincides with the well-located Wadati-Benioff zone seismicity and perhaps represents the subducting Nazca slab. On the southeast of lake Titicaca, in northern Bolivia, we see a consistently high velocity anomaly

  1. Planting northern red oak: a comparison of stock types

    Treesearch

    J.J. Zaczek; K.C. Steiner; T.W. Bowersox

    1991-01-01

    Height and survival values of northern red oak (Quercus rubra L.) were compared three years after outplanting as functions of: stock types (direct-seeded, 1-0, 2-0, 1-1, 2-1, and 2-year-old seedlings grown in 7.9-liter pots), presence or absence of undercutting in the nursery, and presence or absence of top-clipping when field planting. In all, 33 or...

  2. 21. VIEW OF NORTHERN BRANCH OF HIGHLINE CANAL, SECTION 1, ...

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

    21. VIEW OF NORTHERN BRANCH OF HIGHLINE CANAL, SECTION 1, T1S-R3E, SHOWING NON-PROJECT LAND, STILL DESERT, IN FOREGROUND AND CULTIVATED FIELDS OF THE SALT RIVER PROJECT BELOW THE CANAL, LOOKING NORTH. A SMALL PORTION OF NON-IRRIGABLE LAND BELOW THE CANAL IS SHOWN AT LEFT, March 1990 - Highline Canal & Pumping Station, South side of Salt River between Tempe, Phoenix & Mesa, Tempe, Maricopa County, AZ

  3. Northern Forest DroughtNet: A New Framework to Understand Impacts of Precipitation Change on the Northern Forest Ecosystem

    NASA Astrophysics Data System (ADS)

    Asbjornsen, H.; Rustad, L.; Templer, P. H.; Jennings, K.; Phillips, R.; Smith, M.

    2014-12-01

    Recent trends and projections for future change for the U.S. northern forests suggest that the region's climate is becoming warmer, wetter, and, ironically, drier, with more precipitation occurring as large events, separated by longer periods with no precipitation. However, to date, precipitation manipulation experiments conducted in forest ecosystems represent only ~5% of all such experiments worldwide, and our understanding of how the mesic-adapted northern forest will respond to greater frequency and intensity of drought in the future is especially poor. Several important challenges have hampered previous research efforts to conduct forest drought experiments and draw robust conclusions, including difficulties in reducing water uptake by deep and lateral tree roots, logistical and financial constraints to establishing and maintaining large-scale field experiments, and the lack of standardized approaches for determining the appropriate precipitation manipulation treatment (e.g., amount and timing of throughfall displacement), designing and constructing the throughfall displacement infrastructure, identifying key response variables, and collecting and analyzing the field data. The overarching goal of this project is to establish a regional research coordination network - Northern Forest DroughtNet - to investigate the impacts of changes in the amount and distribution of precipitation on the hydrology, biogeochemistry, and carbon (C) cycling dynamics of northern temperate forests. Specific objectives include the development of a standard prototype for conducting precipitation manipulation studies in forest ecosystems (in collaboration with the international DroughtNet-RCN) and the implementation of this prototype drought experiment at the Hubbard Brook Experimental Forest. Here, we present the advances made thus far towards achieving the objectives of Northern Forest DroughtNet, plans for future work, and an invitation to the larger scientific community interested

  4. Geologic map of the northern plains of Mars

    USGS Publications Warehouse

    Tanaka, Kenneth L.; Skinner, James A.; Hare, Trent M.

    2005-01-01

    The northern plains of Mars cover nearly a third of the planet and constitute the planet's broadest region of lowlands. Apparently formed early in Mars' history, the northern lowlands served as a repository both for sediments shed from the adjacent ancient highlands and for volcanic flows and deposits from sources within and near the lowlands. Geomorphic evidence for extensive tectonic deformation and reworking of surface materials through release of volatiles occurs throughout the northern plains. In the polar region, Planum Boreum contains evidence for the accumulation of ice and dust, and surrounding dune fields suggest widespread aeolian transport and erosion. The most recent regional- and global-scale maps describing the geology of the northern plains are largely based on Viking Orbiter image data (Dial, 1984; Witbeck and Underwood, 1984; Scott and Tanaka, 1986; Greeley and Guest, 1987; Tanaka and Scott, 1987; Tanaka and others, 1992a; Rotto and Tanaka, 1995; Crumpler and others, 2001; McGill, 2002). These maps reveal highland, plains, volcanic, and polar units based on morphologic character, albedo, and relative ages using local stratigraphic relations and crater counts. This geologic map of the northern plains is the first published map that covers a significant part of Mars using topography and image data from both the Mars Global Surveyor and Mars Odyssey missions. The new data provide a fresh perspective on the geology of the region that reveals many previously unrecognizable units, features, and temporal relations. In addition, we adapted and instituted terrestrial mapping methods and stratigraphic conventions that we think result in a clearer and more objective map. We focus on mapping with the intent of reconstructing the history of geologic activity within the northern plains, including deposition, volcanism, erosion, tectonism, impact cratering, and other processes with the aid of comprehensive crater-density determinations. Mapped areas include all

  5. Hammersley Range, northern Western Australia

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The oval shaped basin of the sedimentary rocks of the Hammersley Range, northern Western Australia (23.0S, 119.0E) dominates the center of this near nadir view. The Fortescue River is the remarkably straight, fault controlled feature bordering the Hammersley on the north. Sand dunes are the main surface features in the northeast and southwest. Many dry lakebeds can be seen to the east as light grey colored patches along the watercourses.

  6. Carrion use by northern goshawks

    Treesearch

    John R. Squires

    1995-01-01

    Northern goshawks (Accipiter gentilis) feed on a wide variety of birds and mammals (R. T. Reynolds, et al. 1992, USDA For. Ser. Gen. Tech. Rep. RM-217. Fort Collins, CO U.S.A.), but few accounts describe goshawks feeding on carrion. J.H. Schnell (1958, Condor 60:377-403) stated that, "It seems highly unlikely that the goshawk would forage for carrion under normal...

  7. Ceres Northern Hemisphere in Survey

    NASA Image and Video Library

    2015-06-10

    Craters in the northern hemisphere of dwarf planet Ceres are seen in this image taken by NASA's Dawn spacecraft on June 6, 2015. This is among the first snapshots from Dawn's second mapping orbit, which is 2,700 miles (4,400 kilometers) in altitude. The resolution is 1,400 feet (410 meters) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA19570

  8. Hammersley Range, northern Western Australia

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The oval shaped basin of the sedimentary rocks of the Hammersley Range, northern Western Australia (23.0S, 119.0E) dominates the center of this near nadir view. The Fortescue River is the remarkably straight, fault controlled feature bordering the Hammersley on the north. Sand dunes are the main surface features in the northeast and southwest. Many dry lakebeds can be seen to the east as light grey colored patches along the watercourses.

  9. Hammersley Range, northern Western Australia

    NASA Image and Video Library

    1990-04-29

    The oval shaped basin of the sedimentary rocks of the Hammersley Range, northern Western Australia (23.0S, 119.0E) dominates the center of this near nadir view. The Fortescue River is the remarkably straight, fault controlled feature bordering the Hammersley on the north. Sand dunes are the main surface features in the northeast and southwest. Many dry lakebeds can be seen to the east as light grey colored patches along the watercourses.

  10. The northern Egyptian continental margin

    NASA Astrophysics Data System (ADS)

    Badawy, Ahmed; Mohamed, Gad; Omar, Khaled; Farid, Walid

    2015-01-01

    Africa displays a variety of continental margin structures, tectonics and sedimentary records. The northern Egyptian continental margin represents the NE portion of the North African passive continental margin. Economically, this region is of great importance as a very rich and productive hydrocarbon zone in Egypt. Moreover, it is characterized by remarkable tectonic setting accompanied by active tectonic processes from the old Tethys to recent Mediterranean. In this article, seismicity of the northern Egyptian continental margin has been re-evaluated for more than 100-years and the source parameters of three recent earthquakes (October 2012, January 2013 and July 2013) have been estimated. Moment tensor inversions of 19th October 2012 and 17th January 2013 earthquakes reveal normal faulting mechanism with strike-slip component having seismic moment of 3.5E16 N m and 4.3E15 N m respectively. The operation of the Egyptian National Seismic Network (ENSN) since the end of 1997 has significantly enhanced the old picture of earthquake activity across northern Egyptian continental margin whereas; the record-ability (annual rate) has changed from 2-events/year to 54-event/year before and after ENSN respectively. The spatial distribution of earthquakes foci indicated that the activity tends to cluster at three zones: Mediterranean Ridge (MR), Nile Cone (NC) and Eratosthenes Seamount (ERS). However, two seismic gaps are reported along Levant Basin (LEV) and Herodotus Basin (HER).

  11. Preliminary report on the northern Australian melioidosis environmental surveillance project.

    PubMed Central

    Inglis, T. J. J.; Foster, N. F.; Gal, D.; Powell, K.; Mayo, M.; Norton, R.; Currie, B. J.

    2004-01-01

    An environmental surveillance programme was developed to determine whether water supplies could be a source of Burkholderia pseudomallei as noted during previous melioidosis outbreak investigations. Water supplies to communities in the three northern Australian jurisdictions (Western Australia, Northern Territory and Queensland) were sampled periodically during 2001 and 2002. Water and soil samples were collected from communities known to have had recent culture-positive melioidosis cases and nearby communities where no cases had been diagnosed. Clinical isolates of B. pseudomallei obtained from northern Australian patients during 2001 and 2002 were compared with the environmental B. pseudomallei isolates by ribotyping and pulsed-field gel electrophoresis. B. pseudomallei was isolated from 11 distinct locations, all in the Northern Territory, seven of which were associated with culture-positive melioidosis cases (>1 case at three locations). Water was implicated as a possible environmental source of melioidosis in six locations. A variety of free-living amoebae including Acanthamoeba and Hartmannella spp. that are potential hosts to B. pseudomallei were recovered from environmental specimens. Culturable B. pseudomallei was not found to be widely dispersed in the environments sampled. PMID:15473143

  12. Field Trial Performance of Herculex XTRA (Cry34Ab1/Cry35Ab1) and SmartStax (Cry34Ab1/Cry35Ab1 + Cry3Bb1) Hybrids and Soil Insecticides Against Western and Northern Corn Rootworms (Coleoptera: Chrysomelidae)

    PubMed Central

    Campbell, L. A.; Lepping, M. D.; Rule, D. M.

    2017-01-01

    Abstract Western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), and northern corn rootworm, Diabrotica barberi Smith and Lawrence (Coleoptera: Chrysomelidae), are important insect pests in corn, Zea mays L. For more than a decade, growers have been using transgenic plants expressing proteins from the bacterium Bacillus thuringiensis (Bt) to protect corn roots from feeding. In 2011, western corn rootworm populations were reported to have developed resistance to Bt hybrids expressing Cry3Bb1 and later found to be cross-resistant to hybrids expressing mCry3A and eCry3.1Ab. The identification of resistance to Cry3 (Cry3Bb1, mCry3A, and eCry3.1Ab) hybrids led to concerns about durability and efficacy of products with single traits and of products containing a pyramid of a Cry3 protein and the binary Bt proteins Cry34Ab1 and Cry35Ab1. From 2012 to 2014, 43 field trials were conducted across the central United States to estimate root protection provided by plants expressing Cry34Ab1/Cry35Ab1 alone (Herculex RW) or pyramided with Cry3Bb1 (SmartStax). These technologies were evaluated with and without soil-applied insecticides to determine if additional management measures provided benefit where Cry3 performance was reduced. Trials were categorized for analysis based on rootworm damage levels on Cry3-expressing hybrids and rootworm feeding pressure within each trial. Across scenarios, Cry34Ab1/Cry35Ab1 hybrids provided excellent root protection. Pyramided traits provided greater root and yield protection than non-Bt plus a soil-applied insecticide, and only in trials where larval feeding pressure exceeded two nodes of damage did Cry34Ab1/Cry35Ab1 single-trait hybrids and pyramided hybrids show greater root protection from the addition of soil-applied insecticides. PMID:28430986

  13. Reappraisal of the relationship between the northern Nevada rift and Miocene extension in the northern Basin and Range Province

    USGS Publications Warehouse

    Colgan, Joseph P.

    2013-01-01

    The northern Nevada rift is a prominent mafic dike swarm and magnetic anomaly in north-central Nevada inferred to record the Middle Miocene (16.5-15.0 Ma) extension direction in the northern Basin and Range province in the western United States. From the 245°-250° rift direction, Basin and Range extension is inferred to have shifted 45° clockwise to a modern direction of 290°-300° during the late Miocene. The region surrounding the northern Nevada rift was actively extending while the rift formed, and these domains are all characterized by extension oriented 280°-300°. This direction is distinctly different from the rift direction and nearly identical to the modern Basin and Range direction. Although the rate, structural style, and distribution of Basin and Range extension appear to have undergone a significant change in the late Miocene (ca. 10 Ma), the overall spreading direction does not. Middle Miocene extension was directed perpendicular to the axis of the thickest crust formed during Mesozoic shortening and this orientation may reflect gravitational collapse of this thick crust. Orientation of northern Nevada rift dikes may reflect a short-lived regional stress field related to the onset of Yellowstone hotspot volcanism.

  14. Regional metallogenic structure based on aeromagnetic data in northern Chile

    NASA Astrophysics Data System (ADS)

    Zhu, Xiao-San; Lu, Min-Jie

    2016-12-01

    Chile is a very important country that forms part of the Andean metallogenic belts. The Atacama and Domeyko fault systems in northern Chile control the tectonic-magmatic activities that migrate eastward and the types of mineral resources. In this paper, we processed and interpreted aeromagnetic data from northern Chile using reduction to pole, upward field continuation, the second derivative calculation in the vertical direction, inclination angle calculation, and analytical signal amplitude analysis. We revealed the locations and planar distribution characteristics of the regional deep faults along the NNE and NS directions. Furthermore, we observed that the major reasons for the formation of the tectonic-magmatic rocks belts were the nearly parallel deep faults distributed from west to east and multiple magmatic activities along these faults. We ascertained the locations of volcanic mechanisms and the relationships between them using these regional deep faults. We deduced the spatial distributions of the basic-intermediate, basic, and acidic igneous rocks, intrusive rocks, and sedimentary sequences. We showed the linear positive magnetic anomalies and magnetic anomaly gradient zones by slowly varying the background, negative magnetic anomaly field, which indicated the presence of strong magmatic activities in these regional deep faults; it also revealed the favorable areas of copper and polymetallic mineralization. This study provides some basic information for further research on the geology, structural characteristics, and mineral resource prospecting in northern Chile.

  15. Geothermal systems of northern Nevada

    USGS Publications Warehouse

    Hose, Richard Kenneth; Taylor, Bruce Edward

    1974-01-01

    Hot springs are numerous and nearly uniformly distributed in northern Nevada. Most occur on the flanks of basins, along Basin and Range (late Miocene to Holocene) faults, while some occur in the inner parts of the basins. Surface temperatures of the springs range from slightly above ambient to, boiling; some springs are superheated. Maximum subsurface water temperatures calculated on the basis of quartz solubility range as high as 252?C, although most are below 190?C. Flows range from a trickle to several hundred liters per minute. The Nevada geothermal systems differ markedly from the power-producing system at The Geysers, Calif., and from those areas with a high potential, for power production (e.g., Yellowstone Park, Wyo.; Jemez Mountains, N. Mex.). These other systems are associated with Quaternary felsic volcanic rocks and probably derive their heat from cooling magma rather high in the crust. In northern Nevada, however, felsic volcanic rocks are virtually all older than 10 million years, and. analogous magmatic heat sources are, therefore, probably lacking. Nevada is part of an area of much higher average heat flow than the rest of the United States. In north-central Nevada, geothermal gradients are as great as 64?C per kilometer in bedrock and even higher in basin fill. The high gradients probably result from a combination of thin crust and high temperature upper mantle. We suggest that the geothermal systems of northern Nevada result from circulation of meteoric waters along Basin and Range faults and that their temperature chiefly depends upon (1) depth of circulation and (2) the geothermal gradient near the faults.

  16. Geothermal development plan: northern Arizona

    SciTech Connect

    White, D.H.; Goldstone, L.A.

    1981-01-01

    Much of the northern counties (Apache, Coconino, Gila, Mohave, Navajo and Yavapai) is located in the Colorado Plateau province, a region of low geothermal potential. Two areas that do show some potential are the Flagstaff - San Francisco Peaks area and the Springerville area. Flagstaff is rapidly becoming the manufacturing center of Arizona and will have many opportunities to use geothermal energy to satisfy part of its increasing need for energy. Using a computer simulation model, projections of geothermal energy on line as a function of time are made for both private and city-owned utility development of a resource.

  17. Rattlesnake Bites in Northern California