Helen Sirp - talent kodus ja võõrsil / Auri Jürna

Index Scriptorium Estoniae

Jürna, Auri, 1984-

2013-01-01

Eesti väljapanek "Ministry of Creative Affairs" Londoni moenädalal International Fashion Showcase. Väljapaneku autoriteks Helen Sirp, Kadri Kruus, Kristina Viirpalu, Kristian Steinberg, Karl Annus. Pikemalt Helen Sirbist

Helen Mirreni kuningannad / Jaanus Noormets

Index Scriptorium Estoniae

Noormets, Jaanus

2007-01-01

Stephen Frearsi mängufilm "Kuninganna" ("The Queen") : stsenarist Peter Morgan : kuninganna Elizabeth II kehastab Helen Mirren, peaminister Tony Blair'i Michael Sheen : Suurbritannia, 2006. H. Mirreni filmiauhindadest ja Oscarivõimalustest selle rolli eest

Isotopic Insights Into the Degassing and Secondary Hydration Rates of Volcanic Glass From the 1980 Eruptions of Mount St. Helens

Science.gov (United States)

Seligman, A. N.; Bindeman, I. N.; Van Eaton, A. R.; Hoblitt, R. P.

2016-12-01

Following eruption, volcanic glass undergoes hydration in its depositional environment, which overprints the history of magmatic degassing recorded in the glass. However, the rates of secondary hydration of volcanic glass used for paleoclimate studies are poorly constrained. Here, we present our results of a natural experiment using products of the 1980 eruptions of Mount St. Helens. We measured the δD of extracted water and the δ18O of the bulk glass of samples collected during the dry summer months of 1980 and compared them with material resampled in August of 2015. Results demonstrate that only samples collected from the subsurface near gas escape pipes show elevated water concentrationss (near 2.0 wt.%) and low δD (-110 to -130 ‰) and δ18O (6.0 to 6.6 ‰) values, and that the initial process of secondary hydration is not always a simple addition of low δD waters at ambient temperature. On average, the 2015 surface samples have slightly higher water contents (0.1-0.2 wt.%) and similar δ18O (6.8 - 6.9 ‰) to those collected in 1980. Given the moderate vesicularity of the samples and the slow rate of surface temperature diffusion, we attribute these observations to hydration during cooling, with only little exchange after. We also compare our results to rapidly quenched air fall pumice from the May 18th eruption, which shows moderate δD values (-74 ‰) and water concentrations (0.3 wt.%) that are closer to those for the 1980 samples. Surprisingly, the 2015 surface samples show higher δD values (+15 ‰), which we attribute to any of four possibilities: (1) evaporation or (2) degassing of underlying deposits; (3) exchange of hydrogen with local vegetation; and/or (4) microlite crystallization that aided diffusion of water. Reconstructed δD-H2O trends for the Mount St. Helens samples collected in 1980 support previous studies proposing that exsolved volatiles were trapped within a rapidly rising magma that degassed at shallow depths. The dacitic Mount

Helen Hart, remarkable plant pathologist (1900-1971).

Science.gov (United States)

Wilcoxson, R D

1996-01-01

Helen Hart was a Professor of Plant Pathology at the University of Minnesota from 1924 until retirement in 1966. Born in Janeville, Wisconsin, she died at Grants Pass, Oregon. Her scholarly research concentrated on wheat stem rust to understand host pathogen relationships and to develop rust-resistant cultivars. She did not teach formal courses but was heavily involved in making seminars a vital part of instruction, in teaching languages needed for graduate studies, and as an informal advisor for most rust research theses. She had common sense, excellent scientific judgment, and sound instincts on personnel matters that served the department well. A talented science writer, Hart served as editor of hundreds of theses and departmental manuscripts for publication. Her writing and editing skills were used as associate editor of Phytopathology for two years and as editor-in-chief from 1944-1951. A strong advocate of The American Phytopathological Society, Helen Hart served on Council for 12 years and as President in 1956. Helen Hart was a great professional scientist who had a far-reaching impact on plant pathology during the twentieth century.

Dacite – siltstone peperite from Trlično at Rogatec, Eastern Slovenia

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Polona Kralj

2006-06-01

Full Text Available Dacitic glassy lava flow at Trlično is surrounded by a dacite – siltstone peperite and peperitic breccia that underwent alteration, recognised in two, only a few metres thick zones. In the higher-temperature alteration zone, albite extensively replaces volcanic glass and primary plagioclases. The siltstone components are altered to microcrystalline quartz, iron oxides and interlayered illite/smectite clay minerals. This zone developed upon thermalmetamorphosis related to the transfer of heat from the cooling lava. In the lower temperature alteration zone, analcime occurs as the replacement of volcanic glass and pore- and fissure-filling, while the primary plagioclases and poorly lithified siltstone remained fairly unchanged. This zone developed under hydrothermal conditions related to the heating, circulation and reactions of pore waters in the sediment surrounding the lava flow.

Helen Dilloni koduaed Dublinis / Virve Poom

Index Scriptorium Estoniae

Poom, Virve

2015-01-01

Tuntud iiri aiakujundaja Helen Dilloni koduaeda Dublini keskklinnas Sandford Terrace'il peetakse üheks parimaks linnaaiaks. Kaasaegsete aedade hulgas paistab see silma just oma erilisuse ja omanäolisusega

Mount St. Helens aerosol evolution

Energy Technology Data Exchange (ETDEWEB)

Oberbeck, V.R.; Farlow, N.H.

1982-08-01

Stratospheric aerosol samples were collected using a wire impactor during the year following the eruption of Mount St. Helens. Analysis of samples shows that aerosol volume increased for 6 months due to gas-to-particle conversion and then decreased to background levels in the following 6 months.

Mount St. Helens aerosol evolution

Energy Technology Data Exchange (ETDEWEB)

Oberbeck, V.R.; Farlow, N.H.; Fong, W.; Snetsinger, K.G.; Ferry, G.V.; Hayes, D.M.

1982-09-01

Stratospheric aerosol samples were collected using a wire impactor during the year following the eruption of Mt. St. Helens. Analysis of samples show that aerosol volume increased for 6 months due to gas-to-particle conversion and then decreased to background levels in the following 6 months.

78 FR 43064 - Safety Zone; Maritime Heritage Festival Fireworks, St. Helens, OR

Science.gov (United States)

2013-07-19

...-AA00 Safety Zone; Maritime Heritage Festival Fireworks, St. Helens, OR AGENCY: Coast Guard, DHS. ACTION... associated with fireworks displays. As part of the Maritime Heritage Festival Fireworks in St. Helens, OR, the festival will feature a fireworks display. The Coast Guard expects approximately 1,000 people to...

Dacitic ash-flow sheet near Superior and Globe, Arizona

Science.gov (United States)

Peterson, Donald W.

1961-01-01

Remnants of a dacitic ash-flow sheet near Globe, Miama, and Superia, Arizona cover about 100 square miles; before erosion the area covered by the sheet was at least 400 square miles and perhaps as much as 1,500 square miles. Its maximum thickness is about 2,000 feet, its average thickness is about 500 feet, and its original volume was at least 40 cubic miles. It was erupted on an eroded surface with considerable relief. The main part of the deposit was thought by early workers to be a lava flow. Even after the distinctive character of welded tuffs and related rocks was discovered, the nature and origin of this deposit remained dubious because textures did not correspond to those in other welded tuff bodies. Yet a lava flow as silicic as this dacite would be viscous instead of spreading out as an extensive sheet. The purpose of this investigation has been to study the deposit, resolve the inconsistencies, and deduce its origin and history. Five stratigraphic zones are distinguished according to differences in the groundmass. From bottom to top the zones are basal tuff, vitrophyre, brown zone, gray zone, and white zone. The three upper zones are distinguished by colors on fresh surfaces, for each weathers to a similar shade of light reddish brown. Nonwelded basal tuff grades upward into the vitrophyre, which is a highly welded tuff. The brown and gray zones consist of highly welded tuff with a lithoidal groundmass. Degree of welding decreases progressively upward through the gray and the white zones, and the upper white zone is nonwelded. Textures are clearly outlined in the lower part of the brown zone, but upward they become more diffuse because of increasing devitrification. In the white zone, original textures are essentially obliterated, and the groundmass consists of spherulites and microcrystalline intergrowths. The chief groundmass minerals are cristobalite and sanidine, with lesser quartz and plagioclase. Phenocrysts comprise about 40 percent of the rock

May 1980 Mount Saint Helens, USA Images

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — An earthquake occurred at 15 32 UT, only seconds before the explosion that began the eruption of Mount St. Helens volcano. This eruption and blast blew off the top...

The Helen logos and Herodotus’ Fingerprint

NARCIS (Netherlands)

de Jong, I.; Baragwanath, E.; de Bakker, M.

2012-01-01

Herodotus' discussion of the Trojan War in Histories 2.112-20 consists mainly of two strands: a historiographical evaluation of his sources, Homer and the Egyptian priests (116-17, 120), and the presentation of an alternative version (Helen never went to Troy but stayed in Egypt), as heard from the

Friendly Letters on the Correspondence of Helen Keller, Anne Sullivan, and Alexander Graham Bell.

Science.gov (United States)

Blatt, Burton

1985-01-01

Excerpts from the letters between Alexander Graham Bell and Anne Sullivan and Helen Keller are given to illustrate the educational and personal growth of Helen Keller as well as the educational philosophy of Bell regarding the education of the deaf blind. (DB)

Making sense of Mount St. Helens

Science.gov (United States)

Steve Nash

2010-01-01

The eruption of Mount St. Helens in 1980 resulted in "a grand experiment that you could never have gotten anybody to fund," says Forest Service ecologist Charles Crisafulli. "Everything's new. It's a new landform." Unlike most misbehaving volcanoes, this one provided an accessible laboratory right along the Interstate-5 corridor, with the...

Racism, Disable-ism, and Heterosexism in the Making of Helen Keller

OpenAIRE

Prettol, Andy

2008-01-01

In his paper "Racism, Disable-ism, and Heterosexism in the Making of Helen Keller" Andy Prettol offers an analysis of prevailing narratives about Helen Keller. Prettol focuses on the dynamic interplay of race, (dis)ability, sexuality, and gender inherent to all Keller stories of triumph that are so popular in elementary schools across the U.S. He examines three specific works: William Gibson's playscript The Miracle Worker, written in 1956; the film of the same title directed by Arthur Penn i...

Special report: Mt. St. Helens

Science.gov (United States)

Mt. St Helens Volcano, Cascade Range, Southern Washington, USA (46.20°N, 122.18°W.) All times are local (GMT - 7 h through October 24, GMT - 8 h thereafter. Lava extrusion that probably began October 30 added a new lobe to the composite dome in the crater of Mt. St. Helens. After lava extrusion ended September 10 (see September 22 Eos), rates of deformation in the crater remained low for several weeks, as they had after earlier extrusion episodes. Sulfur dioxide emission ranged from 70 to 190 tons per day between October 9 and 24, but showed no particular trends. Inflation of the dome has caused small thrust faults to form in the surrounding crater floor. In early October the most active thrust, south of the dome, was moving at about 1.5 cm/d, and stations on the north crater rampart showed outward movement of about 0.5 cm/d. By October 24 these rates had increased to 14.5 and 3.5-4 cm/d, respectively, and leveling profiles perpendicular to the dome showed that crater floor tilt rates had reached 400-500 μrad/d, prompting the U.S. Geological Survey (USGS) to issue an advisory prediction of renewed lava extrusion within the next two weeks.

The opsis of Helen: Performative Intertextuality in Euripides

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Aspasia Skouroumouni Stavrinou

2015-02-01

Full Text Available Features of the play’s staging, costume, and gestures achieve a series of allusions to comparable features in the genre of comedy and thus reinforce the comic elements of the plot and characters of Helen.

Mount St. Helens, 1980 to now—what’s going on?

Science.gov (United States)

Dzurisin, Daniel; Driedger, Carolyn L.; Faust, Lisa M.

2013-01-01

Mount St. Helens seized the world’s attention in 1980 when the largest historical landslide on Earth and a powerful explosive eruption reshaped the volcano, created its distinctive crater, and dramatically modified the surrounding landscape. An enormous lava dome grew episodically in the crater until 1986, when the volcano became relatively quiet. A new glacier grew in the crater, wrapping around and partly burying the lava dome. From 1987 to 2003, sporadic earthquake swarms and small steam explosions indicated that magma (molten rock) was being replenished deep underground. In 2004, steam-and-ash explosions heralded the start of another eruption. A quieter phase of continuous lava extrusion followed and lasted until 2008, building a new dome and doubling the volume of lava on the crater floor. Scientists with the U.S. Geological Survey and University of Washington’s Pacific Northwest Seismograph Network maintain constant watch for signs of renewed activity at Mount St. Helens and other Cascade volcanoes. Now is an ideal time for both actual and virtual visitors to Mount St. Helens to learn more about dramatic changes taking place on and beneath this active volcano.

Helen Lehismets võitis vaibakavandite konkursi / Lea Pruuli

Index Scriptorium Estoniae

Pruuli, Lea

1999-01-01

Tarbekunstimuuseumi vaibakavandite konkursil "Kootud pildid" valiti teostamiseks tekstiilikunstnik Helen Lehismetsa vaibakavand "Aed". Ostupreemia ئ Urmas Viigi kavandile "EW ja AW". Osalejad. Konkursile esitatud kavandeid ja vaibaks kootud peapreemiatööd eksponeeritakse Tarbekunstimuuseumis 22. okt. avataval näirtusel "Kootud pildid".

Isotopic insights into the degassing and secondary hydration of volcanic glass from the 1980 eruptions of Mount St. Helens

Science.gov (United States)

Seligman, Angela N.; Bindeman, Ilya; Van Eaton, Alexa; Hoblitt, Richard

2018-04-01

Abstract The magmatic degassing history of newly erupted volcanic glass is recorded in its remaining volatile content. However, this history is subsequently overprinted by post-depositional (secondary) hydration, the rates and origins of which are not yet adequately constrained. Here, we present the results of a natural experiment using products of the 1980 eruptions of Mount St. Helens. We measured water concentration, δDglass, and δ18OBSG (δ18O of the bulk silicate glass) of samples collected during the dry summer months of 1980 and compared them with material resampled in 2015 from the same deposits. Samples collected from the subsurface near gas escape pipes show elevated water concentrations (near 2.0 wt%), and these are associated with lower δDglass (- 110 to - 130‰) and δ18OBSG (6.0 to 6.6‰) values than the 1980 glass (- 70 to - 100‰ and 6.8 to 6.9‰, respectively). Samples collected in 2015 from the surface to 10-cm subsurface of the 1980 summer deposits have a small increase in average water contents of 0.1-0.2 wt% but similar δ18OBSG (6.8-6.9‰) values compared to the 1980 glass values. These samples, however, show 15‰ higher δDglass values; exchange with meteoric water is expected to yield lower δDglass values. We attribute higher δDglass values in the upper portion of the 1980 deposits collected in 2015 to rehydration by higher δD waters that were degassed for several months to a year from the hot underlying deposits, which hydrated the overlying deposits with relatively high δD gases. Our data also contribute to magmatic degassing of crystal-rich volcanoes. Using the 1980 samples, our reconstructed δD-H2O trends for the dacitic Mount St. Helens deposits with rhyolitic groundmass yield a trend that overlaps with the degassing trend for crystal-poor rhyolitic eruptions studied previously elsewhere, suggesting similar behavior of volatiles upon exsolution from magma. Furthermore, our data support previous studies proposing that

Mafic enclaves in dacitic domes and their relation with La Poruña scoria cone, Central Andes, northern Chile

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González-Maurel, O. P.; Gallmeyer, G.; Godoy, B.; Menzies, A.; le Roux, P. J.; Harris, C.

2017-12-01

Chao Dacite, Chillahuita, Cerro Pabellón, Chanka, Chac-Inca, and Cerro La Torta (or Tocorpuri) are dacitic domes of late Pleistocene age (30 to 140 ka; Renzulli et al., 2006; Tierney et al., 2016) located in Northern Chilean Central Andean province (NCCA; 17°20'S - 27°40'S). While, La Poruña is a 180 m high basaltic-andesite scoria cone erupted ca. 100 ka (Wörner et al., 2000). This scoria cone is also located at the NCCA, 26 km to the SW of Chanka and 45 km to the NW of Chao Dacite. The dacitic domes are generally porphyritic and highly crystalline lavas (30 - 50 vol % phenocrysts, plagioclase > biotite > amphibole > quartz ≥ accessory), with hyalopilitic or intersertal groundmass. These domes contain mafic enclaves, mostly andesite in composition, with plagioclase > amphibole > biotite ≥ clinopyroxene ≥ olivine ≥ accessory phenocryst (10 - 20 vol %) in a lightly oxidized groundmass with intersertal or intergranular textures. In contrast, La Poruña rocks are mostly aphanitic (75 - 85 vol % groundmass) and highly vesicular, with plagioclase > olivine ≥ clinopyroxene ≥ orthopyroxene phenocrysts in an intersertal or hyalopilitic groundmass. Although petrographically different, the composition (57 wt % SiO2; 580 ppm Sr, 87Sr/86Sr = 0.7066) of mafic enclaves from Cerro Pabellón dome are similar to the lava flows and pyroclastic blocks of La Poruña scoria cone (55 - 59 wt % SiO2; 560 - 610 ppm Sr; 0.7062 - 0.7066 87Sr/86Sr). Based on this data and the eruption ages of these volcanic structures, we suggest that the mafic enclaves and La Poruña magmas are co-genetic. Thus, we propose that the genesis of these mafic enclaves is associated with the origin of less evolved parental magmas erupted in the NCCA, such as those from La Poruña. In this case, the mafic enclaves would represent batches of less evolved magmas that ascended from deeper sources and probably contributed in the eruption of the dacitic domes. Renzulli et al., 2006. In XI Congreso Geol

Changes in seismic velocity during the first 14 months of the 2004–2008 eruption of Mount St. Helens, Washington

Science.gov (United States)

Hotovec-Ellis, A.J.; Vidale, J.E.; Gomberg, Joan S.; Thelen, Weston A.; Moran, Seth C.

2015-01-01

Mount St. Helens began erupting in late 2004 following an 18 year quiescence. Swarms of repeating earthquakes accompanied the extrusion of a mostly solid dacite dome over the next 4 years. In some cases the waveforms from these earthquakes evolved slowly, likely reflecting changes in the properties of the volcano that affect seismic wave propagation. We use coda-wave interferometry to quantify small changes in seismic velocity structure (usually <1%) between two similar earthquakes and employed waveforms from several hundred families of repeating earthquakes together to create a continuous function of velocity change observed at permanent stations operated within 20 km of the volcano. The high rate of earthquakes allowed tracking of velocity changes on an hourly time scale. Changes in velocity were largest near the newly extruding dome and likely related to shallow deformation as magma first worked its way to the surface. We found strong correlation between velocity changes and the inverse of real-time seismic amplitude measurements during the first 3 weeks of activity, suggesting that fluctuations of pressure in the shallow subsurface may have driven both seismicity and velocity changes. Velocity changes during the remainder of the eruption likely result from a complex interplay of multiple effects and are not well explained by any single factor alone, highlighting the need for complementary geophysical data when interpreting velocity changes.

Obituary: Helen Dodson Prince, 1905-2002

Science.gov (United States)

Lindner, Rudi Paul

2009-01-01

Helen Dodson Prince, a pioneer in the observation of solar flares, a pioneer in women's rise in the profession of astronomy, and a respected and revered educator of future astronomers, died on 4 February 2002 in Arlington, Virginia. Helen Dodson was born in Baltimore, Maryland, on 31 December 1905. Her parents were Helen Walter and Henry Clay Dodson. Helen went to Goucher College in nearby Towson with a full scholarship in mathematics. She turned to astronomy under the influence of a legendary teacher, Professor Florence P. Lewis, and she graduated in 1927. Funded by grants and private charity, she earned the Ph.D. in astronomy at the University of Michigan under the direction of Heber Doust Curtis in 1933. Dodson taught at Wellesley College from 1933 until 1943, when she went on leave to spend the last three years of World War II at the MIT Radiation Laboratory. She returned to Goucher after the war as professor of astronomy and mathematics, and in 1947 she came back to Michigan both as professor of astronomy and staff member of the McMath-Hulbert Observatory, of which she became associate director. In 1976 she retired from Michigan and spent her later years in Alexandria, Virginia. In 1932 Dodson held the Dean Van Meter fellowship from Goucher; in 1954 she received the Annie Jump Cannon Prize from the AAS; and in 1974 The University of Michigan honored her with its Faculty Distinguished Achievement Award. She published over 130 articles, mostly on her research specialty, solar flares. Dodson's interest in the Sun began at Michigan, although her dissertation was, like so many Michigan dissertations of the era, on stellar spectroscopy, "A Study of the Spectrum of 25 Orionis." She came to Michigan during the establishment and growth of the solar observatory at Lake Angelus, the creation of three gifted and industrious amateurs. Heber Curtis fostered the growth of the McMath-Hulbert enterprise and brought it into the University. Dodson's solar activity grew as a

Storia di un Vulcano I GPS di Trimble per monitorare Mount St. Helen

Directory of Open Access Journals (Sweden)

Edoardo Carlucci

2005-10-01

Full Text Available Venticinque anni fa il peggior disastro vulcanico nella storia degli Stati Uniti attirò l’attenzione di tutto il mondo. L’esplosione, preceduta da un paio di mesi di piccole scosse di terremoto, squarciò il fianco Nord del vulcano St. Helens il 18 maggio 1980, provocando allo stesso tempo il più grande smottamento della storia. L’eruzione seguente all’esplosione cancellò tutta l’area circostante, facendo 57 vittime tra la popolazione e formando un profondo cratere a forma di ferro di cavallo; per sei anni si susseguirono altre piccole eruzioni che portarono alla formazione di un’altra cupola lavica dopodiché Loo-wit (il Guardiano del Fuoco, come i nativi americani usavano chiamare il vulcano St. Helens, si addormentò di nuovo. Prima del fatidico giorno Mount St. Helens era la nona cima per altezza negli Stati Uniti; dopo il 18 maggio essa diventava la trentesima.

The "Unsavory Researches" of Helen Campbell: A 19th-Century Journalist's Investigation of Urban Women's Poverty.

Science.gov (United States)

Henry, Susan

In 1886, the New York "Tribune" ran a series of articles by Helen Campbell, "The Prisoners of Poverty," which investigated the sufferings of working women in New York's slums. Initially a fiction and housekeeping writer, Helen Campbell's home economics orientation first pointed her toward the problems of the poor. In the late…

The 1994-2001 eruptive period at Rabaul, Papua New Guinea: Petrological and geochemical evidence for basalt injections into a shallow dacite magma reservoir, and significant SO2 flux

Science.gov (United States)

Patia, H.; Eggins, S. M.; Arculus, R. J.; McKee, C. O.; Johnson, R. W.; Bradney, A.

2017-10-01

The eruptions that began at Rabaul Caldera on 19 September 1994 had two focal points, the vents Tavurvur and Vulcan, located 6 km apart on opposing sides of the caldera. Vulcan eruptives define a tight cluster of dacite compositions, whereas Tavurvur eruptives span an array from equivalent dacite compositions to mafic andesites. The eruption of geochemically and mineralogically identical dacites from both vents indicates sourcing from the same magma reservoir. This, together with previously reported H2O-CO2 volatile contents of dacite melt inclusions, a caldera-wide seismic low-velocity zone, and a seismically active caldera ring fault structure are consistent with the presence at 3-6 km depth of an extensive, tabular dacitic magma body having volume of about 15-150 km3. The Tavurvur andesites form a linear compositional array and have strongly bimodal phenocryst assemblages that reflect dacite hybridisation with a mafic basalt. The moderately large volume SO2 flux documented in the Tavurvur volcanic plume (and negligible SO2 flux in the Vulcan plume) combined with high dissolved S contents of basaltic melt inclusions trapped in olivine of Tavurvur eruptives, indicate that the amount of degassed basaltic magma was 0.1 km3 and suggest that the injection of this magma was confined to the Tavurvur-side (eastern to northeastern sector) of the caldera. Circumstantial evidence suggests that the eruption was triggered and evolved in response to a series of basaltic magma injections that may have commenced in 1971 and continued up until at least the start of the 1994 eruptions. The presence of zoned plagioclase phenocrysts reflecting older basalt-dacite interaction events (i.e. anorthite cores overgrown with thick andesine rims), evaluation of limited available data for the products of previous eruptions in 1878 and 1937-1943, and the episodic occurrence of major intra-caldera seismo-deformational events indicates that the shallow magma system at Rabaul Caldera is

Helen Howitt: una semilla canadiense en la enfermería latinoamericana Helen Howitt: uma semente canadense na enfermagem latino-americana Helen Howitt: A Canadian seed in Latin American nursing

Directory of Open Access Journals (Sweden)

ANA LUISA VELANDIA MORA

2009-07-01

Full Text Available Este trabajo se propone hacer visible la presencia de Helen Howitt en la enfermería latinoamericana. Paralelamente pretende hacer un análisis de la influencia política del Servicio Cooperativo Interamericano de Salud Pública en la enfermería de la región y la presencia de organizaciones religiosas, especialmente norteamericanas, en varios países latinoamericanos. Helen Howitt, enfermera canadiense egresada de la Universidad de Alberta, fue enviada en 1942 por la Organización Panamericana de la Salud, OPS para que asesorara en Colombia al Ministerio de Trabajo, Higiene y Previsión Social. Pasó a formar parte del proyecto de apertura y organización de la Escuela Nacional Superior de Enfermeras, y fue su primera directora. Helen Howitt fue directora de la Escuela de Enfermería del Hospital Santo Tomás de la Zona del Canal de Panamá entre 1933 y 1938, luego fundadora y primera directora de la Escuela Nacional Superior de Enfermeras de Colombia entre los años 1943 y 1951; posteriormente de la Escuela Nacional de Enfermeras de Bolivia entre 1953 y 1959, cuando fue invitada a cumplir un cargo similar en Venezuela. A todos estos países llegó primero como consultora del respectivo Ministerio de Salud, a través de convenios con el Servicio Cooperativo Interamericano de Salud Pública. La Fundación Rockefeller daba becas para todos los países latinos. En la Escuela del Hospital Santo Tomás de Panamá había estudiantes de toda la América Central, Venezuela, Colombia, hasta del Ecuador y la Argentina. La Rockefeller quería unificar la enfermería en toda Latinoamérica. Llegó primero a Venezuela; y las enfermeras que se graduaron en Panamá fueron las líderes en América Latina, donde trataron de fundar escuelas.O presente trabalho pretende visibilizar a presença de Hellen Howitt na enfermagem latino-americana. Paralelamente, procura fazer uma análise sobre a influência política do Serviço Cooperativo Interamericano de Sa

Helen Howitt: una semilla canadiense en la enfermería latinoamericana Helen Howitt: A Canadian seed in Latin American nursing Helen Howitt: uma semente canadense na enfermagem latino-americana

Directory of Open Access Journals (Sweden)

VELANDIA MORA ANA LUISA

2009-07-01

Full Text Available Este trabajo se propone hacer visible la presencia de Helen Howitt en la enfermería latinoamericana. Paralelamente pretende hacer un análisis de la influencia política del Servicio Cooperativo Interamericano de Salud Pública en la enfermería de la región y la presencia de organizaciones religiosas, especialmente norteamericanas, en varios países latinoamericanos. Helen Howitt, enfermera canadiense egresada de la Universidad de Alberta, fue enviada en 1942 por la Organización Panamericana de la Salud, OPS para que asesorara en Colombia al Ministerio de Trabajo, Higiene y Previsión Social. Pasó a formar parte del proyecto de apertura y organización de la Escuela Nacional Superior de Enfermeras, y fue su primera directora. Helen Howitt fue directora de la Escuela de Enfermería del Hospital Santo Tomás de la Zona del Canal de Panamá entre 1933 y 1938, luego fundadora y primera directora de la Escuela Nacional Superior de Enfermeras de Colombia entre los años 1943 y 1951; posteriormente de la Escuela Nacional de Enfermeras de Bolivia entre 1953 y 1959, cuando fue invitada a cumplir un cargo similar en Venezuela. A todos estos países llegó primero como consultora del respectivo Ministerio de Salud, a través de convenios con el Servicio Cooperativo Interamericano de Salud Pública. La Fundación Rockefeller daba becas para todos los países latinos. En la Escuela del Hospital Santo Tomás de Panamá había estudiantes de toda la América Central, Venezuela, Colombia, hasta del Ecuador y la Argentina. La Rockefeller quería unificar la enfermería en toda Latinoamérica. Llegó primero a Venezuela; y las enfermeras que se graduaron en Panamá fueron las líderes en América Latina, donde trataron de fundar escuelas.This work's purpose is to make more visible Hellen Howitt's presence in Latin American nursing. At the same time it pretends to make an analysis on the political influence of the Interamerican Cooperative Public

Amphibole trace elements as indicators of magmatic processes at Mount St. Helens

Science.gov (United States)

Hampel, T. R.; Rowe, M. C.; Kent, A.; Thornber, C. R.

2011-12-01

Amphibole has the capability of incorporating a wide variety of trace elements resulting from a range of magmatic processes. Prior studies have used trace elements such as Li and Cu in amphibole to investigate volatile mobility associated with magma ascent regarding the 2004-2008 eruption of Mount St. Helens (Rowe et al. 2008). In order to investigate magmatic processes associated with the 2004-2008 eruption of Mount St. Helens we have measured a range of fluid-mobile trace elements in conjunction with major element compositions of amphibole phenocrysts in dacite lava. Major elements and volatiles (Cl, F) were measured by electron microprobe analysis at Washington State University and trace elements (Li, Sc, Co, Cu, Zn, Sr, Y, Zr, Mo, Ag, Sn, Sb, Te, Ba, Ce, W, and Pb) were analyzed by laser ablation (LA)-ICP-MS at Oregon State University. Amphibole crystallization temperatures were calculated after Ridolfi et al. (2010). Core to rim transects were measured by electron microprobe to evaluate volatile concentrations and temperature profiles across individual phenocrysts. Core temperatures from 17 days and 226 days post eruption are consistently hotter than the rim temperatures 997 to 881 degrees C, respectively. Amphiboles from the end of the eruption (811 days post eruption) appear to be more complex, with phenocrysts having both increasing and decreasing temperatures toward the rims. The overall calculated temperature range of the amphiboles at the end of the eruption is 1022 to 919 degrees C. There is much diversity in the concentrations of Li and Cu within the phenocrysts in both the samples and throughout the eruption. Concentrations steadily increase in the beginning of the eruption then drop dramatically toward the middle, slowly increase toward the end eruption. Overall concentrations of Sr, Sb, Co, Sn, Mo, Ba, Ce, Sc, and Y do not change over the course of the eruption but do vary sample to sample. Preliminary data for Zn, Sb, Ag, and W suggest the

Large-amplitude traveling ionospheric distrubance produced by the May 18, 1980, explosion of Mount St. Helens

International Nuclear Information System (INIS)

Roberts, D.H.; Klobuchar, J.A.; Fougere, P.F.; Hendrickson, D.H.

1982-01-01

A remarkable long-lived, large-scale traveling ionospheric disturbance (TID), excited by the May 18, 1980, explosion of Mount St. Helens, has been detected in total electron content monitor data. Oscillatory perturbations in the electron column density of the ionosphere with amplitudes about 10% of the nominal daytime content were detected at three stations whose ionospheric penetration points lie between 1610 and 1890 km from Mount St. Helens. Smaller perturbations were detected at five of six additional stations between 3760 and 4950 km away. The period of the TID increased linearly with great-circle distance from Mount St. Helens, ranging from roughly-equal37 min at the nearest station to roughly-equal116 min at the most distant one. The TID persisted for at least four cycles at the three close stations and three cycles at the more distant stations and was qualitatively similar to TID's produced by the low-altitude thermonuclear detonations of the 1960's. The disturbance front of this TID accelerated from an average velocity of roughly-equal350 m/s between Mt. St. Helens and the close stations to an average velocity of roughly-equal550 m/s to the more distant ones.A model based on the free wave response of an isothermal atmosphere to a point disturbance provides a good fit to the data at the three closest stations, but no such model can account for all of the data. Modeling of the long-distance behavior of the Mount St. Helens TID in terms of upper-atmosphere guided gravity waves is complicated by the requirement of exciting them by a ground-level explosion. There was no evidence for a strong supersonic shock wave in the ionosphere. As a result, the Mount St. Helens disturbance may prove to be a cleaner test of detailed theories of the point excitation and propagation of gravity waves in a realistic atmosphere than were TID's excited by thermonuclear weapons

Pre-eruptive conditions of dacitic magma erupted during the 21.7 ka Plinian event at Nevado de Toluca volcano, Central Mexico

Science.gov (United States)

Arce, J. L.; Gardner, J. E.; Macías, J. L.

2013-01-01

The Nevado de Toluca volcano in Central Mexico has been active over the last ca. 42 ka, during which tens of km3 of pyroclastic material were erupted and two important Plinian-type eruptions occurred at ca. 21.7 ka (Lower Toluca Pumice: LTP) and ca. 10.5 ka (Upper Toluca Pumice: UTP). Samples from both the LTP and UTP contain plagioclase, amphibole, iron-titanium oxides, and minor anhedral biotite, set in a vesicular, rhyolitic, glassy matrix. In addition, UTP dacites contain orthopyroxene. Analysis of melt inclusions in plagioclase phenocrysts yields H2O contents of 2-3.5 wt.% for LTP and 1.3-3.6 wt.% for UTP samples. Ilmenite-ulvospinel geothermometry yields an average temperature of ~ 868 °C for the LTP magma (hotter than the UTP magma, ~ 842 °C; Arce et al., 2006), whereas amphibole-plagioclase geothermometry yields a temperature of 825-859 °C for the LTP magma. Water-saturated experiments using LTP dacite suggest that: (i) amphibole is stable above 100 MPa and below 900 °C; (ii) plagioclase crystallizes below 250-100 MPa at temperatures of 850-900 °C; and (iii) pyroxene is stable only below pressures of 200-100 MPa and temperatures of 825-900 °C. Comparison of natural and experimental data suggests that the LTP dacitic magma was stored at 150-200 MPa (5.8-7.7 km below the volcano summit). No differences in pressure found between 21.7 ka and 10.5 ka suggest that these two magmas were stored at similar depths. Orthopyroxene produced in lower temperature LTP experiments is compositionally different to those found in UTP natural samples, suggesting that they originated in two different magma batches. Whole-rock chemistry, petrographic features, and mineral compositions suggest that magma mixing was responsible for the generation of the dacitic Plinian LTP eruption.

Mount St. Helens 30 years later: a landscape reconfigured.

Science.gov (United States)

Rhonda Mazza

2010-01-01

On May 18, 1980, after two months of tremors, Mount St. Helens erupted spectacularly and profoundly changed a vast area surrounding the volcano. The north slope of the mountain catastrophically failed, forming the largest landslide witnessed in modern times. The largest lobe of this debris avalanche raced 14 miles down the Toutle River...

Colonos y soldados en Oriente Helenístico

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Adolfo Domínguez Monedero

1994-01-01

Full Text Available Este artículo estudia las formas que asume el asentamiento de soldados en el mundo helenístico. En primer lugar, se estudia la época de Alejandro Magno en cuanto que precedente; en efecto, Alejandro ha utilizado en gran medida a sus soldados para fundar nuevas colonias, que son un medio de proteger y defender sus conquistas. Este procedimiento ha sido igualmente empleado por sus sucesores, los reyes helenísticos. Aquí estudio ante todo los reinos Seiéucida y Tolemaico, haciendo especial hincapié en los diferentes métodos de los que cada uno de ellos se ha servido, y los distintos fines que debía alcanzar cada una de sus respectivas políticas de asentamiento. Del mismo modo, en cada uno de los tres casos abordados me detengo ante todo en las relaciones entre macedonios, griegos, indígenas y no griegos en general en las nuevas fundaciones. Como conclusión, se resalta el sentido general de todo el proceso en la conformación del mundo helenístico.This paper analyzes the ways in which the settlement of soldiers has been accomplished in the Hellenistic world. Firstly, I study the age of Alexander the Great as a precedent; Alexander has greatly used his soldiers in the foundation of new colonies as a way to protect and defend his conquests. This procedure has been also used by his successors, the Hellenistic kings. I study mainly the Seleucid and the Ptolemaic Kingdoms, stressing the different ways each of them has used, and the different purposes of their different settiement politics. In the three cases deait the relations between Macedonians, Greeks, Natives and non-greeks in general in the new foundations are underlined. As a conclusión the overall meaning of all the process in the shaping of the Hellenistic worid is emphasized.

25 years of ecological change at Mount St. Helens.

Science.gov (United States)

V.H. Dale; C.M. Crisafulli; F.J. Swanson

2005-01-01

18 May 2005 marks the 25th anniversary of the massive eruption of Mount St. Helens. This eruption involved diverse geological processes (1) that disturbed forests, meadows, lakes, an drivers (2) (see the figure). A huge landslide and searing flows of hot gases and pumic framents (pyroclastic flows) inundated 60 km2 of land, obliterating...

Proximal ecological effects of the 1980 eruptions of Mount St. Helens

Science.gov (United States)

Swanson, F. J.

1988-01-01

The diversity of ecosystems and volcanic processes involved in the 1980 eruptions of Mount St. Helens, southwest Washington, provide an excellent setting for examining effects of volcanic events on ecosystems. These eruptions included a lateral blast, debris avalanche, mudflows, pyroclastic flows, and airfall tephra. Affected ecosystems within 30 km of the vent were lakes, streams, upland and riparian forest, and meadows. Ecological disturbances imposed by the Mount St. Helens events were predominantly physical, rather than climatic or chemical which are the dominant classes of disturbances considered in analysis of global catastrophes. Analysis of ecosystem response to disturbance should be based on consideration of composition and structure of the predisturbance system in terms that represent potential survivability of organisms, mechanisms in the primary disturbance, initial survivors, secondary disturbances arising from the primary disturbance and the biological responses to secondary disturbances, invasion of the site by new propagules, interactions among secondary disturbance processes and surviving and invading organisms. Predicting ecosystem response to disturbance is enchanced by considering the mechanisms of disturbance rather than type of disturbance. In the 1980 Mount St. Helens events, the disturbance types, involved primarily the mechanisms of sedimentation, heating, and shear stress. Each disturbance type involved one or more mechanisms. Ecosystem response varied greatly across the landscape. Analysis of ecosystem response to disturbance, regardless of type, should include detailed consideration of the properties of individual species, primary and secondary disturbance mechanisms, and their distributions across landscapes.

Chemical Analysis of Reaction Rims on Olivine Crystals in Natural Samples of Black Dacite Using Energy-Dispersive X-Ray Spectroscopy, Lassen Peak, CA.

Science.gov (United States)

Graham, N. A.

2014-12-01

Lassen Volcanic Center is the southernmost volcanic region in the Cascade volcanic arc formed by the Cascadia Subduction Zone. Lassen Peak last erupted in 1915 in an arc related event producing a black dacite material containing xenocrystic olivine grains with apparent orthopyroxene reaction rims. The reaction rims on these olivine grains are believed to have formed by reactions that ensued from a mixing/mingling event that occurred prior to eruption between the admixed mafic andesitic magma and a silicic dacite host material. Natural samples of the 1915 black dacite from Lassen Peak, CA were prepared into 15 polished thin sections and carbon coated for analysis using a FEI Quanta 250 Scanning Electron Microscope (SEM) to identify and measure mineral textures and disequilibrium reaction rims. Observed mineralogical textures related to magma mixing include biotite and amphibole grains with apparent dehydration/breakdown rims, pyroxene-rimmed quartz grains, high concentration of microlites in glass matrix, and pyroxene/amphibole reaction rims on olivine grains. Olivine dissolution is evidenced as increased iron concentration toward convolute edges of olivine grains as observed by Backscatter Electron (BSE) imagery and elemental mapping using NSS spectral imaging software. In an attempt to quantify the area of reaction rim growth on olivine grains within these samples, high-resolution BSE images of 30 different olivine grains were collected along with Energy-Dispersive X-Ray Spectroscopy (EDS) of different phases. Olivine cores and rims were extracted from BSE images using Photoshop and saved as separate image files. ImageJ software was used to calculate the area (μm2) of the core and rim of these grains. Average pyroxene reaction rim width for 30 grains was determined to be 11.68+/-1.65 μm. Rim widths of all 30 grains were averaged together to produce an overall average rim width for the Lassen Peak black dacite. By quantifying the reaction rims on olivine grains

Mount St. Helens: Still erupting lessons 31 years later

Science.gov (United States)

Rhonda Mazza; Charlie Crisafulli; Fred Swanson

2011-01-01

The massive volcanic eruption of Mount St. Helens 31 years ago provided the perfect backdrop for studying the earliest stages of forest development. Immediately after the eruption, some areas of the blast area were devoid of life. On other parts of the volcanic landscape, many species survived, although their numbers were greatly reduced. Reassembly began at many...

Petrogenesis of andesites and dacites of White Island volcano, Bay of Plenty, New Zealand, in the light of new geochemical and isotopic data

International Nuclear Information System (INIS)

Graham, I.J.; Cole, J.W.

1991-01-01

White Island volcano comprises three main lava types: (1) silicic andesite, forming Western Cone and a tholoid at Troup Head, (2) dacite forming the Central Cone, and (3) mafic-silicic andesite erupted in March 1977 from the currently active crater. All lavas are calc-alkalic and medium-K orogenic types. The older andesites of Western Cone and Troup Head were probably formed from chemically dissimilar parental magmas by processes of assimilation and fractional crystallisation (AFC). Andesite blocks and bombs ejected during phreatomagmatic activity in March 1977 are geochemically primitive having high Mg-numbers, high Cr and Ni contents, and containing forsteritic olivine. They cannot be derived from magmatic compositions similar to known basaltic lavas of Taupo Volcanic Zone, and it is possible that the blocks are hybrid magmas resulting from mixing of a high Mg basalt parent and Central Cone dacite. The bombs appear to be fractionated derivatives. Central Cone dacites may also be AFC derivatives of a common parent to the 1977 lavas, in which substantial chemical diffusion has occurred. Their earlier eruption might represent unloading of a zoned magma chamber. (author). 49 refs., 8 figs., 3 tabs

Balti aadlipreili kunstiharrastusest : Helene Marie Zoege von Manteuffel (1773/74-1842) = Artistic pursuits of an aristocratic Baltic lady : Helene Marie Zoege von Manteuffel (1773/74-1842) / Kadi Polli

Index Scriptorium Estoniae

Polli, Kadi, 1973-

2014-01-01

Aadlitüdrukute haridusest ja kunstiharidusest Balti valgustusaja kunsti(haridus)maastikul. Perekond Zoege von Manteuffeli kunstilembusest ja Ojasoo mõisa tähtsusest baltisaksa kunstiajaloos. Helene Mariest Franz Gerhard Kügelgeni õpilasena ja abikaasana

Helen Mirren võitis Elizabeth II rolliga brittide Oscari / Triin Tael

Index Scriptorium Estoniae

Tael, Triin

2007-01-01

Stephen Frearsi mängufilmis "Kuninganna" ("The Queen") kuninganna Elizabeth II kehastav Helen Mirren sai oma rolli eest parima naisnäitleja Bafta (Briti filmiakadeemia auhind). Linateos pälvis ka aasta parima filmi tiitli. Ka teistest võitjatest

Satellite sar detection of hurricane helene (2006)

DEFF Research Database (Denmark)

Ju, Lian; Cheng, Yongcun; Xu, Qing

2013-01-01

In this paper, the wind structure of hurricane Helene (2006) over the Atlantic Ocean is investigated from a C-band RADARSAT-1 synthetic aperture radar (SAR) image acquired on 20 September 2006. First, the characteristics, e.g., the center, scale and area of the hurricane eye (HE) are determined. ...... observations from the stepped frequency microwave radiometer (SFMR) on NOAA P3 aircraft. All the results show the capability of hurricane monitoring by satellite SAR. Copyright © 2013 by the International Society of Offshore and Polar Engineers (ISOPE)....

Isocrates’ Encomium of Helen: Reply to Gorgias and the Unicity of his Epideictic Discourse

Directory of Open Access Journals (Sweden)

Ticiano Curvelo Estrela de Lacerda

2017-06-01

Full Text Available Around 390-80 BC, the Athenian Isocrates composed one of his first speeches as an educator, the Helen. According to most scholars, this speech seems to be a replica to the famous Eulogy of Helen by Gorgias, which, according to Isocrates (§14, would have made not an encomium, but an apology on behalf of the Spartan queen. In the Isocratic encomium, we noticed some dissonance between the proemium and the rest of the work. In fact, we do not have in the proemium the expected laudatory tone, but it is configured, on the contrary, as an invective to sophists groups contemporary of Isocrates, and culminates in the end with an allusive criticism of the Leontine sophist. Thus, what the IV century BC sophists have in common with the mythical Helen? In other words, would there be a common thread that would ensure a discursive unity in that epideictic exercise of Isocrates? This study aims to discuss these issues and review how they are being discussed by some commentators of Isocrates, since the Rhetoric of Aristotle to the reception of the matter among some scholars of Classical Rhetoric in the XX century.

An Overview of the Dynamics of the Volcanic Paroxysmal Explosive Activity, and Related Seismicity, at Andesitic and Dacitic Volcanoes (1960–2010

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Vyacheslav M. Zobin

2018-05-01

Full Text Available Understanding volcanic paroxysmal explosive activity requires the knowledge of many associated processes. An overview of the dynamics of paroxysmal explosive eruptions (PEEs at andesitic and dacitic volcanoes occurring between 1960 and 2010 is presented here. This overview is based mainly on a description of the pre-eruptive and eruptive events, as well as on the related seismic measurements. The selected eruptions are grouped according to their Volcanic Explosivity Index (VEI. A first group includes three eruptions of VEI 5-6 (Mount St. Helens, 1980; El Chichón, 1982; Pinatubo, 1991 and a second group includes three eruptions of VEI 3 (Usu volcano, 1977; Soufriere Hills Volcano (SHV, 1996, and Volcán de Colima, 2005. The PEEs of the first group have similarity in their developments that allows to propose a 5-stage scheme of their dynamics process. Between these stages are: long (more than 120 years period of quiescence (stage 1, preliminary volcano-tectonic (VT earthquake swarm (stage 2, period of phreatic explosions (stage 3 and then, PEE appearance (stage 4. It was shown also that the PEEs of this group during their Plinian stage “triggered” the earthquake sequences beneath the volcanic structures with the maximum magnitude of earthquakes proportional to the volume of ejecta of PEEs (stage 5. Three discussed PEEs of the second group with lower VEI developed in more individual styles, not keeping within any general scheme. Among these, one PEE (SHV may be considered as partly following in development to the PEEs of the first group, having stages 1, 3, and 4. The PEEs of Usu volcano and of Volcán de Colima had no preliminary long-term stages of quiescence. The PEE at Usu volcano came just at the end of the preceding short swarm of VT earthquakes. At Volcán de Colima, no preceding swarm of VT occurred. This absence of any regularity in development of lower VEI eruptions may refer, among other reasons, to different conditions of opening

Tähistame Helen Kelleri 130. sünniaastapäeva

Index Scriptorium Estoniae

Keskküla, Raissa

2010-01-01

Helen Kellerist ja tema sünniaastapäeva tähistamisest, samuti Eesti Pimekurtide Tugiliidu ettevõtmistest: koostöölepingust Eesti Kujurite Ühendusega, punktkirjas väljaantud raamatust "Õppimise ime", Hilton/Perkins programmi kaasabil Eesti pimekurtide ja nägemis-liitpuudega lastega töötavate õpetajate ning töötajate koolitamiset

Volcano ecology: flourishing on the flanks of Mount St. Helens

Science.gov (United States)

Rhonda Mazza; Charlie Crisafulli

2016-01-01

Mount St. Helens’ explosive eruption on May 18, 1980, was a pivotal moment in the field of disturbance ecology. The subsequent sustained, integrated research effort has shaped the development of volcano ecology, an emerging field of focused research. Excessive heat, burial, and impact force are some of the disturbance mechanisms following an eruption. They are also...

Helen M. Walker: Influential in 1929 and Still Cited Today.

Science.gov (United States)

Rice, Marti H.; Stallings, William M.

Helen M. Walker contributed to the field of educational research and statistics during a 55-year career. Born in Iowa in 1891, Walker earned a bachelor's degree from Iowa Wesleyan College and taught high school mathematics for nine years. She then taught at the University of Kansas while doing graduate work. One source noted that she was the first…

Tupikteid ei ole / Aimi Püüa, Kristina Orion, Helen Põllo, Kaie Piiskop

Index Scriptorium Estoniae

2015-01-01

Innove õppekava ja metoodika keskuse juhataja Kaie Piiskop, testide ja uuringute keskuse juht Aimi Püüa, karjääriteenuste üksuse juht Kristina Orion, haridus- ja teadusministeeriumi kutsehariduse osakonna juhataja Helen Põllo arutlesid teemal kuidas jätkata haridusteed

Patterns in Seismicity at Mt St Helens and Mt Unzen

Science.gov (United States)

Lamb, Oliver; De Angelis, Silvio; Lavallee, Yan

2014-05-01

Cyclic behaviour on a range of timescales is a well-documented feature of many dome-forming volcanoes. Previous work on Soufrière Hills volcano (Montserrat) and Volcán de Colima (Mexico) revealed broad-scale similarities in behaviour implying the potential to develop general physical models of sub-surface processes [1]. Using volcano-seismic data from Mt St Helens (USA) and Mt Unzen (Japan) this study explores parallels in long-term behaviour of seismicity at two dome-forming systems. Within the last twenty years both systems underwent extended dome-forming episodes accompanied by large Vulcanian explosions or dome collapses. This study uses a suite of quantitative and analytical techniques which can highlight differences or similarities in volcano seismic behaviour, and compare the behaviour to changes in activity during the eruptive episodes. Seismic events were automatically detected and characterized on a single short-period seismometer station located 1.5km from the 2004-2008 vent at Mt St Helens. A total of 714 826 individual events were identified from continuous recording of seismic data from 22 October 2004 to 28 February 2006 (average 60.2 events per hour) using a short-term/long-term average algorithm. An equivalent count will be produced from seismometer recordings over the later stages of the 1991-1995 eruption at MT Unzen. The event count time-series from Mt St Helens is then analysed using Multi-taper Method and the Short-Term Fourier Transform to explore temporal variations in activity. Preliminary analysis of seismicity from Mt St Helens suggests cyclic behaviour of subannual timescale, similar to that described at Volcán de Colima and Soufrière Hills volcano [1]. Frequency Index and waveform correlation tools will be implemented to analyse changes in the frequency content of the seismicity and to explore their relations to different phases of activity at the volcano. A single station approach is used to gain a fine-scale view of variations in

VP Structure of Mount St. Helens, Washington, USA, imaged with local earthquake tomography

Science.gov (United States)

Waite, G.P.; Moran, S.C.

2009-01-01

We present a new P-wave velocity model for Mount St. Helens using local earthquake data recorded by the Pacific Northwest Seismograph Stations and Cascades Volcano Observatory since the 18 May 1980 eruption. These data were augmented with records from a dense array of 19 temporary stations deployed during the second half of 2005. Because the distribution of earthquakes in the study area is concentrated beneath the volcano and within two nearly linear trends, we used a graded inversion scheme to compute a coarse-grid model that focused on the regional structure, followed by a fine-grid inversion to improve spatial resolution directly beneath the volcanic edifice. The coarse-grid model results are largely consistent with earlier geophysical studies of the area; we find high-velocity anomalies NW and NE of the edifice that correspond with igneous intrusions and a prominent low-velocity zone NNW of the edifice that corresponds with the linear zone of high seismicity known as the St. Helens Seismic Zone. This low-velocity zone may continue past Mount St. Helens to the south at depths below 5??km. Directly beneath the edifice, the fine-grid model images a low-velocity zone between about 2 and 3.5??km below sea level that may correspond to a shallow magma storage zone. And although the model resolution is poor below about 6??km, we found low velocities that correspond with the aseismic zone between about 5.5 and 8??km that has previously been modeled as the location of a large magma storage volume. ?? 2009 Elsevier B.V.

Environmental Impact of the Helen, Research, and Chicago Mercury Mines on Water, Sediment, and Biota in the Upper Dry Creek Watershed, Lake County, California

Science.gov (United States)

Rytuba, James J.; Hothem, Roger L.; May, Jason T.; Kim, Christopher S.; Lawler, David; Goldstein, Daniel; Brussee, Brianne E.

2009-01-01

The Helen, Research, and Chicago mercury (Hg) deposits are among the youngest Hg deposits in the Coast Range Hg mineral belt and are located in the southwestern part of the Clear Lake volcanic field in Lake County, California. The mine workings and tailings are located in the headwaters of Dry Creek. The Helen Hg mine is the largest mine in the watershed having produced about 7,600 flasks of Hg. The Chicago and Research Hg mines produced only a small amount of Hg, less than 30 flasks. Waste rock and tailings have eroded from the mines, and mine drainage from the Helen and Research mines contributes Hg-enriched mine wastes to the headwaters of Dry Creek and contaminate the creek further downstream. The mines are located on federal land managed by the U.S. Bureau of Land Management (USBLM). The USBLM requested that the U.S. Geological Survey (USGS) measure and characterize Hg and geochemical constituents in tailings, sediment, water, and biota at the Helen, Research, and Chicago mines and in Dry Creek. This report is made in response to the USBLM request to conduct a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA - Removal Site Investigation (RSI). The RSI applies to removal of Hg-contaminated mine waste from the Helen, Research, and Chicago mines as a means of reducing Hg transport to Dry Creek. This report summarizes data obtained from field sampling of mine tailings, waste rock, sediment, and water at the Helen, Research, and Chicago mines on April 19, 2001, during a storm event. Further sampling of water, sediment, and biota at the Helen mine area and the upper part of Dry Creek was completed on July 15, 2003, during low-flow conditions. Our results permit a preliminary assessment of the mining sources of Hg and associated chemical constituents that could elevate levels of monomethyl Hg (MMeHg) in the water, sediment, and biota that are impacted by historic mining.

Helen Howitt: una semilla canadiense en la enfermería latinoamericana

Directory of Open Access Journals (Sweden)

ANA LUISA VELANDIA MORA

2009-07-01

Full Text Available Este trabajo se propone hacer visible la presencia de Helen Howitt en la enfermería latinoamericana. Paralelamente pretende hacer un análisis de la influencia política del Servicio Cooperativo Interamericano de Salud Pública en la enfermería de la región y la presencia de organizaciones religiosas, especialmente norteamericanas, en varios países latinoamericanos. Helen Howitt, enfermera canadiense egresada de la Universidad de Alberta, fue enviada en 1942 por la Organización Panamericana de la Salud, OPS para que asesorara en Colombia al Ministerio de Trabajo, Higiene y Previsión Social. Pasó a formar parte del proyecto de apertura y organización de la Escuela Nacional Superior de Enfermeras, y fue su primera directora. Helen Howitt fue directora de la Escuela de Enfermería del Hospital Santo Tomás de la Zona del Canal de Panamá entre 1933 y 1938, luego fundadora y primera directora de la Escuela Nacional Superior de Enfermeras de Colombia entre los años 1943 y 1951; posteriormente de la Escuela Nacional de Enfermeras de Bolivia entre 1953 y 1959, cuando fue invitada a cumplir un cargo similar en Venezuela. A todos estos países llegó primero como consultora del respectivo Ministerio de Salud, a través de convenios con el Servicio Cooperativo Interamericano de Salud Pública. La Fundación Rockefeller daba becas para todos los países latinos. En la Escuela del Hospital Santo Tomás de Panamá había estudiantes de toda la América Central, Venezuela, Colombia, hasta del Ecuador y la Argentina. La Rockefeller quería unificar la enfermería en toda Latinoamérica. Llegó primero a Venezuela; y las enfermeras que se graduaron en Panamá fueron las líderes en América Latina, donde trataron de fundar escuelas.

Application of PIXE to the characterization of vitreous dacites from archaeolgical sites in the Atacama region in northern Chile

Energy Technology Data Exchange (ETDEWEB)

Morales, J.R.; Cancino, S. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Nunoa, Santiago 1 (Chile); Miranda, P. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Nunoa, Santiago 1 (Chile)], E-mail: pjmirand@gmail.com; Dinator, M.I. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Nunoa, Santiago 1 (Chile); Seelenfreund, A. [Universidad Academia de Humanismo Cristiano, Condell 343, Providencia, Santiago (Chile)

2007-11-15

Geochemical characterization studies using PIXE were carried out on 21 vitreous dacite artifacts from early formative archaeological sites in the Atacama region, in northern Chile, and on 13 samples taken from two potential volcanic sources located within the region. Performing statistical analyses it was possible to obtain elemental concentration patterns for the archaeological samples of this material and match some of these artifacts with the geological source samples.

Precambrian tholeiitic-dacitic rock-suites and Cambrian ultramafic rocks in the Pennine nappe system of the Alps: Evidence from Sm-Nd isotopes and rare earth elements

Science.gov (United States)

Stille, P.; Tatsumoto, M.

1985-04-01

Major element, trace element and Sm-Nd isotope analyses were made of polymetamorphic hornblendefelses, plagioclase amphibolites and banded amphibolites from the Berisal complex in the Simplon area (Italy, Switzerland) to determine their age, origin and genetic relationships. In light of major and rare earth element data, the hornblendefelses are inferred to have originally been pyroxene-rich cumulates, the plagioclase amphibolites and the dark layers of the banded amphibolites to have been tholeiitic basalts and the light layers dacites. The Sm-Nd isotope data yield isochron ages of 475±81 Ma for the hornblendefelses, 1,018±59 Ma for the plagioclase amphibolites and 1,071±43 Ma for the banded amphibolites. The 1 Ga magmatic event is the oldest one ever found in the crystalline basement of the Pennine nappes. The Sm -Nd isotope data support the consanguinity of the tholeiitic dark layers and the dacitic light layers of the banded amphibolites with the tholeiitic plagioclase amphibolites and the ultramafic hornblendefelses. The initial ɛ Nd values indicate that all three rock types originated from sources depleted in light rare earth elements. We suggest that plagioclase and banded amphibolites were a Proterozoic tholeiite-dacite sequence that was strongly deformed and flattened during subsequent folding. The hornblendefelses are thought to be Cambrian intrusions of pyroxene-rich material.

Helene: A Plastic Model

Science.gov (United States)

Umurhan, O. M.; Moore, J. M.; Howard, A. D.; Schenk, P.; White, O. L.

2014-12-01

Helene, the Saturnian L4 Trojan satellite co-orbiting Dionne and sitting within the E-ring, possesses an unusual morphology characteristic of broad km-scale basins and depressions and a generally smooth surface patterned with streaks and grooves which are indicative of non-typical mass transport. Elevation angles do not appear to exceed 10o at most. The nature and origin of the surface materials forming these grooved patterns is unknown. Given the low surface gravity (plastic-like flow like a Bingham fluid, we setup and test a number of likely scenarios to explain the observations. The numerical results qualitatively indicate that treating the mass-wasting materials as a Bingham material reproduces many of the qualitative features observed. We also find that in those simulations in which accretion is concomitant with Bingham mass-wasting, the long time-evolution of the surface flow shows intermittency in the total surface activity (defined as total surface integral of the absolute magnitude of the mass-flux). Detailed analyses identify the locations where this activity is most pronounced and we will discuss these and its implications in further detail.

Zwischen Aufbegehren und bürgerlicher Rolle: die Lebensgemeinschaft von Helene Lange und Gertrud Bäumer The partnership of Helene Lange und Gertrud Bäumer: a both rebellious and domestic way of life

Directory of Open Access Journals (Sweden)

Mechthilde Vahsen

2001-07-01

Full Text Available Die Forschungsarbeiten analysieren private weibliche Beziehungsformen und ihre Bedeutung für die erste deutsche Frauenbewegung. Im Zentrum der Betrachtung steht eines der wichtigsten Führungspaare dieser Zeit: Helene Lange und Gertrud Bäumer. Die Dissertation von Göttert liefert einen wichtigen Beitrag zur Netzwerkforschung, Schaser beschäftigt sich in ihrer innovativen Studie mit der Lebensgemeinschaft der beiden Frauen, die sie in die frauenbewegten und politischen Kontexte einordnet.These studies analyse the private aspects of female relationship and their significance for the first wave of the German women’s movement. The focus is on the leading couple at that particular time: Helene Lange and Gertrud Bäumer. The dissertation by Göttert contributes an important piece to the network research, whereas Schaser describes in her innovative study the partnership of the two women, which is strongly related to the feminist and political context.

Zircon reveals protracted magma storage and recycling beneath Mount St. Helens

Science.gov (United States)

Claiborne, L.L.; Miller, C.F.; Flanagan, D.M.; Clynne, M.A.; Wooden, J.L.

2010-01-01

Current data and models for Mount St. Helens volcano (Washington, United States) suggest relatively rapid transport from magma genesis to eruption, with no evidence for protracted storage or recycling of magmas. However, we show here that complex zircon age populations extending back hundreds of thousands of years from eruption age indicate that magmas regularly stall in the crust, cool and crystallize beneath the volcano, and are then rejuvenated and incorporated by hotter, young magmas on their way to the surface. Estimated dissolution times suggest that entrained zircon generally resided in rejuvenating magmas for no more than about a century. Zircon elemental compositions reflect the increasing influence of mafic input into the system through time, recording growth from hotter, less evolved magmas tens of thousands of years prior to the appearance of mafic magmas at the surface, or changes in whole-rock geochemistry and petrology, and providing a new, time-correlated record of this evolution independent of the eruption history. Zircon data thus reveal the history of the hidden, long-lived intrusive portion of the Mount St. Helens system, where melt and crystals are stored for as long as hundreds of thousands of years and interact with fresh influxes of magmas that traverse the intrusive reservoir before erupting. ?? 2010 Geological Society of America.

Leonardo da Vinci jõudis Tallinna / Orest Kormašov, Helen Kokk ; intervjueerinud Ants Juske

Index Scriptorium Estoniae

Kormašov, Orest, 1964-

2010-01-01

Kadrioru Kunstimuuseumis eksponeeritakse 5.-12. veebruarini 2010. a. Leonardo da Vinci arvatavat autoportreed. Itaalia kunstiajaloolased kaasasid autoportree uurimisse Tallinna Ülikooli maaliosakonna juhataja Orest Kormašovi, kes teostas klassikalise portreeskulptuuri, ja Eesti Kunstiakadeemia graafilise disaini tudengi Helen Koka, kes valmistas arvutiimitatsiooni

Effects on the Mount St. Helens volcanic cloud on turbidity at Ann Arbor, Michigan

International Nuclear Information System (INIS)

Ryznar, E.; Weber, M.R.; Hallaron, T.S.

1981-01-01

Measurements of turbidity were made at the University of Michigan irradiance and metorlogical measurement facility just prior to, during and after the passage of the volcanic cloud from the 18 May 1980 eruption of Mount St. Helens. They were made with a Volz sunphotometer at wavelengths of 500 and 880 nm

Kuidas toetate sel õppeaastal oma valla koolilapsi? / Külle Viks, Helen Metsma, Aivar Surva...[jt.

Index Scriptorium Estoniae

2009-01-01

Küsimusele vastavad: Türi vallavalitsuse haridusspetsialist Külle Viks, Sõmerpalu valla lastekaitse ja sotsiaaltoetuste spetsialist Helen Metsma, Mäetaguse vallavanem Aivar Surva, Rapla abivallavanem Imbi Kalberg, Kärdla linna haridusnõunik Juta Alev, Albu vallavalitsuse sotsiaalnõunik Claire Miljukova, Võru linnavalitsuse haridusspetsialist Kristi Aavakivi

Sulfur diffusion in dacitic melt at various oxidation states: Implications for volcanic degassing

Science.gov (United States)

Lierenfeld, Matthias Bernhard; Zajacz, Zoltán; Bachmann, Olivier; Ulmer, Peter

2018-04-01

The diffusivity of S in a hydrous dacitic melt (4.5-6.0 wt.% H2O) has been investigated in the temperature (T) and pressure (P) range of 950 °C to 1100 °C and 200 to 250 MPa, respectively. Three series of experiments were conducted at relatively low oxygen fugacity (fO2) conditions [0.8 log units below fayalite-magnetite-quartz equilibrium (FMQ -0.8); referred to as "low fO2"] and high fO2 conditions (FMQ +2.5; referred to as "high fO2") to determine if the diffusivity of S is affected by its oxidation state and speciation. Sulfur concentration profiles were measured by electron microprobe and the diffusion coefficient (D) was calculated by fitting these profiles. Sulfur diffusion is approximately one order of magnitude faster when S is dominantly present as sulfide species (low fO2) in comparison to the sulfate dominated experiments (high fO2). The following Arrhenian equations were obtained for high and low fO2 conditions at 200 MPa: high fO2: D = 10-5.92±0.86 * exp ({-137.3±21.5 kJ/mol}/{RT}) low fO2: D = 10-5.18±1.39 * exp ({-125.7±34.4 kJ/mol}/{RT}) where D is the average diffusion coefficient in m2 s-1, R is the gas constant in 8.3144 J mol-1 K-1 and T is the temperature in K. Our results demonstrate for the first time in natural melts that S diffusion is strongly sensitive to fO2. Our S diffusivities under low fO2 conditions are only slightly slower of those found for H2O, suggesting that S can be rather efficiently purged from reduced dacitic melts during volcanic eruptions. However, for more oxidized systems (e.g. subduction zones), S diffusion will be much slower and will hinder equilibrium syn-eruptive degassing during rapid decompression. Therefore, we conclude that the "excess" measured during many explosive volcanic eruptions in arcs is dominantly derived from S-rich bubble accumulation in the eruptible portion of the magma reservoir.

Rhetoric, Possibility, and Women's Status in Ancient Athens: Gorgias' and Isocrates' Encomiums of Helen.

Science.gov (United States)

Biesecker, Susan L.

1992-01-01

Critiques teleological narrative structures implicit in the work of some classical historians, adopting instead a multilayered historiographical method. Argues that a law instituted in 451/450 B.C.E. by Pericles opened up a possibility for resisting women's exclusion from the public sphere. Reads Gorgias' and Isocrates' speeches on Helen of Troy…

Water sampling at the Berge Helene FPSO at Chinguetti field in Mauritania using passive samplers

NARCIS (Netherlands)

Korytar, P.; Galien, van der W.

2007-01-01

Three rounds of water sampling were performed at the Berge Helene FPSO at the Chinguetti field in Mauritania using passive samplers attached to the FPSO to determine the levels of contamination that could potentially accumulate in organisms. Two rounds were carried out prior to the commencement of

A Gentle Frost: Poet Helen Frost Talks about the Healing Power of Poetry and Her Latest Novel

Science.gov (United States)

Margolis, Rick

2006-01-01

This article presents an interview with poet Helen Frost. Frost talked about how poetry can help at-risk children. She also related the challenges she faced when she wrote her latest book titled "The Braid."

Resonancias Vocales y Memoria Sonora en Helen Brown

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Andrés Grumann Sölter

2016-09-01

Full Text Available El artículo se concentra en indagar aspectos referidos a la intensificación de los usos de la voz y la sonorización musical que proponen Trinidad Piriz y Daniel Marabolí en Helen Brown (2013. Dando cuenta de un marco teórico que cuestiona la dimensión referencial con la que se analiza frecuentemente al teatro y proponiendo una aproximación fenomenológica que dé cuenta de la materialidad performativa que insta a intensificar las resonancias de la voz y la capacidad audible del sonido, el escrito analiza dos escenas o tracks en los que la memoria hecha cuerpo compromete de un modo particular a los espectadores que participan de la performance escénica.

Mount St. Helens: Controlled-source audio-frequency magnetotelluric (CSAMT) data and inversions

Science.gov (United States)

Wynn, Jeff; Pierce, Herbert A.

2015-01-01

This report describes a series of geoelectrical soundings carried out on and near Mount St. Helens volcano, Washington, in 2010–2011. These soundings used a controlled-source audio-frequency magnetotelluric (CSAMT) approach (Zonge and Hughes, 1991; Simpson and Bahr, 2005). We chose CSAMT for logistical reasons: It can be deployed by helicopter, has an effective depth of penetration of as much as 1 kilometer, and requires less wire than a Schlumberger sounding.

Posteruption arthropod succession on the Mount St. Helens volcano: the ground-dwelling beetle fauna (Coleoptera).

Science.gov (United States)

R.R. Parmenter; C.M. Crisafulli; N. Korbe; G. Parsons; M. Edgar; J.A. MacMahon

2005-01-01

The 1980 eruptions of Mount St. Helens created a complex mosaic of disturbance types over a 600 km2 area. From 1980 through 2000 we monitored beetle species relative abundance and faunal composition of assemblages at undisturbed reference sites and in areas subjected to tephra-fall, blowdown, and pyroclastic flow volcanic disturbance. We...

Evaluation of radon progeny from Mount St. Helens eruptions. Final report

International Nuclear Information System (INIS)

Lepel, E.A.; Olsen, K.B.; Thomas, V.W.; Eichner, F.N.

1982-09-01

A network of twelve monitoring sites around Mount St. Helens was established to evaluate possible short-lived radioactivity in the fallen ash. Seven sites were located near major population centers of Washington and Oregon, and five sites were located within 80 km of the volcano. Each site monitored the radioactivity present by the use of thermoluminescent dosimeters which recorded the total exposure to radioactivity over the exposure period. Eruptions occurring on July 22, August 7, and October 16 to 18, 1980 were monitored. No statistically significant quantities of measurable radon daughters were observed

Fermilab's Helen Edwards receives prestigious 2003 Robert R. Wilson prize from the American Physical Society

CERN Multimedia

2002-01-01

Helen Edwards has been awarded the 2003 Robert R. Wilson prize. She was cited for "her pivotal achievement and critical contribution as the leader in the design, construction, commissioning and operation of the Tevatron, and for her continued contributions to the development of high gradient superconducting linear accelerators as well as bright and intense electron sources." (1/2 page).

Photogrammetric Analysis of the Current Dome-Building Eruption of Mount St. Helens Volcano

Science.gov (United States)

Diefenbach, A. K.; Dzurisin, D.; Crider, J. G.; Schilling, S. P.

2006-12-01

Beginning in October 2004 and continuing to present day, the eruption of Mount St. Helens has provided a unique opportunity to experiment with new tools and techniques to study the dome-building eruption of a Cascade volcano. At the onset of eruption, a permanent camera station called Sugar Bowl was installed on the northeast rim of the crater about 2 km from the vent. Since that time, four additional cameras have been installed on the rim and crater floor to provide continuous visual observation of dome growth and crater conditions. We have analyzed images from four of the cameras to measure variations in three-dimensional lineal growth rates of lava spines extruding from the growing dome. Using photogrammetric techniques it is possible to obtain quantitative information on the geometry and displacement of a changing topographic model, in this case the evolving dome and glaciers in the crater of Mount St. Helens. The technique is an inexpensive, high-resolution, and efficient method that uses standard commercial software and an off-the-shelf digital camera to determine the x, y, z positions of selected points on the model surface. The model geometry at any given time is defined by the positions of all the points, and displacements are measured by tracking the changing positions of the points through time. Lineal extrusion rates during the first few months of the eruption ranged from 6-11 m/d, and subsequent estimates by other techniques were 4-5 m/d (Dzurisin et. al, 2005). For the past six months the extrusion rate has leveled off at 1 m/d, possibly indicative of steady-state extrusion or an approaching pause in the eruption. Another aspect of the project involves the use of overlapping oblique photos taken from a helicopter in 2004 and 2005 to produce fast and coarse digital elevation models (DEMs), which supplement high resolution DEMs produced by the USGS every 1 - 2 months. Comparing these results with seismicity and ground tilt measured by shallow borehole

GeoGirls: A Geology and Geophysics Field Camp for Middle School Girls at Mount St. Helens

Science.gov (United States)

Samson, C.; Allstadt, K.; Melander, S.; Groskopf, A.; Driedger, C. L.; Westby, E.

2015-12-01

The August 2015 GeoGirls program was a project designed to inspire girls to gain an appreciation and enthusiasm for Earth sciences using Mount St. Helens as an outdoor volcanic laboratory. Occupations in the field of science and engineering tend to be held by more males than females. One way to address this is to introduce girls to possible opportunities within the geosciences and encourage them to learn more about the dynamic environment in which they live. In 2015, the GeoGirls program sought to accomplish this goal through organizing a five day-long field camp for twenty middle school-aged girls, along with four high school-aged mentors and two local teachers. This group explored Mount St. Helens guided by female scientists from the USGS Cascade Volcano Observatory (CVO), the Mount St. Helens Institute (MSHI), UNAVCO, Boise State, Georgia Tech, University of Washington and Oregon State University. To introduce participants to techniques used by volcanologists, the girls participated in hands-on experiments and research projects focusing on seismology, GPS, terrestrial lidar, photogrammetry, water and tephra. Participants also learned to collect samples, analyze data and use microscopes. Through this experience, participants acquired strategies for conducting research by developing hypotheses, making observations, thinking critically and sharing their findings with others. The success of the GeoGirls program was evaluated by participant and parent survey questionnaires, which allowed assessment of overall enthusiasm and interest in pursuing careers in the geosciences. The program was free to participants and was run jointly by MSHI and CVO and funded by NSF, the American Association of University Women, the Association for Women Geoscientists, the Association of Environmental & Engineering Geologists and private donors. The program will run again in the summer of 2016.

Impossible Practice and Theories of the Impossible: A Response to Helene Illeris's "Potentials of Togetherness"

Science.gov (United States)

Kallio-Tavin, Mira

2014-01-01

In a recent commentary in "Studies in Art Education," Helene Illeris (2013) discussed the idea of "performative experimental communities" via a critique of visual culture pedagogy and the romanticism of community-oriented art education in Nordic countries. Illeris underpinned her arguments with Jean-Luc Nancy's (1997)…

Mt. St. Helens' aerosols: some tropospheric and stratospheric effects

International Nuclear Information System (INIS)

Michalsky, J.J.; Stokes, G.M.

1983-01-01

Aerosol optical depth measurements based on the attenuation of direct solar radiation before and after the six major explosive eruptions of Mt. St. Helens during 1980 are presented. These automated measurements are from a site 200 km mostly east and slightly north of the volcano. From the analysis it was concluded that in several cases the conversion of sulfur gases to sulfates proceeded much more rapidly (hours) than is usually found for tropospheric conditions. A possible explanation may be the greater availability of OH due to the presence of substantial water in the plume. The second major result of the analysis was that there was no evidence of a residual aerosol burden. Turbidity data taken between eruptions in 1980 were virtually identical in terms of magnitude and wavelength dependence to 1979 turbidity

Eruption prediction aided by electronic tiltmeter data at mount st. Helens.

Science.gov (United States)

Dzurisin, D; Westphal, J A; Johnson, D J

1983-09-30

Telemetry from electronic tiltmeters in the crater at Mount St. Helens contributed to accurate predictions of all six effusive eruptions from June 1981 to August 1982. Tilting of the crater floor began several weeks before each eruption, accelerated sharply for several days, and then abruptly changed direction a few minutes to days before extrusion began. Each episode of uplift was caused by the intrusion of magma into the lava dome from a shallow source, causing the dome to inflate and eventually rupture. Release of magma pressure and increased surface loading by magma added to the dome combined to cause subsidence just prior to extrusion.

On the Social Nature of Objectivity: Helen Longino and Justin Biddle

Directory of Open Access Journals (Sweden)

Jaana Eigi

2015-11-01

Full Text Available According to Helen Longino, objectivity is necessarily social as it depends on critical interactions in community. Justin Biddle argues that Longino’s account presupposes individuals that are completely open to any criticism; as such individuals are in principle able to criticise their beliefs on their own, Longino's account is not really social. In the first part of my paper I argue that even for completely open individuals, criticism for maintaining objectivity is only possible in community. In the second part I challenge Biddle’s interpretation of Longino’s conception of the individual. I conclude that Longino’s account is necessarily social.

Polyphony and counterpoint: Mechanisms of seduction in the diaries of Helen Hessel and Henri Pierre Roché

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Catherine du Toit

2015-06-01

Polifonie en kontrapunt: Meganismes van verleiding in die dagboeke van Helen Hessel en Henri Pierre Roché. Henri Pierre Roché (1879–1959, outeur van Jules et Jim, word beskryf as ‘n sosiale koppelaar, ‘n model-liefhebber van alles en nog wat, ‘n versamelaar van vroue en kuns en een van die mees produktiewe dagboekskrywers en aktiewe minnaars in die opgetekende geskiedenis. Roché het ‘n reeks sketse oor Don Juan gepubliseer en was geboei deur die figuur van die verleier. In sy twintigs beplan hy om sy lewe te wy aan die skepping van ‘n œuvre wat die morele, intellektuele, sosiale en seksuele verhoudings tussen mans en vrouens sou ondersoek. Ter bereiking van hierdie doel, rig hy sy lewe in as laboratorium waarin werklike ondervindinge dien as hoofbron van inligting. Sy dagboek strek oor sestig jaar en is ryk aan verhale van verleiding. Desnieteenstaande bly die mees intense en boeiende intrige van verleiding en verraad steeds sy verhouding met Helen Hessel. Aan die begin van hulle verhouding, stel Roché voor dat sy ook ‘n dagboek hou van hulle hartstogtelike liefde. Helen Hessel se dagboek, geskryf in Frans, Duits en Engels, reflekteer die drama van verleiding en funksioneer op verskillende vlakke: realisties, visionêr, ten volle geabsorbeer in haar eie gedagtes en emosies en tóg krities jeens haarself en ander. ‘n Vergelyking van die twee dagboeke skep ‘n fassinerende, digte tekstuur wat die binnewerkings blootlê van verleiding in aksie. Die kontrapunt geskep deur hierdie twee interafhanklike stemme word nóg meer kompleks namate ‘n mens bewus word van die intertekstuele verwysings wat bydra tot die ontluikende polifonie van geskrewe liefde en lewe.

Democracy and Schooling in California: The Legacy of Helen Heffernan and Corinne Seeds. Historical Studies in Education

Science.gov (United States)

Weiler, Kathleen

2011-01-01

Helen Heffernan and Corinne Seeds were nationally recognized as leaders of the progressive education movement and were key figures in what was probably the most concerted attempt to put the ideals of progressive education into practice in a state-wide system of public education in the United States. This book examines the struggle over public…

Discovery of Miocene adakitic dacite from the Eastern Pontides Belt (NE Turkey) and a revised geodynamic model for the late Cenozoic evolution of the Eastern Mediterranean region

Science.gov (United States)

Eyuboglu, Yener; Santosh, M.; Yi, Keewook; Bektaş, Osman; Kwon, Sanghoon

2012-08-01

The Cenozoic magmatic record within the ca. 500 km long eastern Pontides orogen, located within the Alpine metallogenic belt, is critical to evaluate the tectonic history and geodynamic evolution of the eastern Mediterranean region. In this paper we report for the first time late Miocene adakitic rocks from the southeastern part of the eastern Pontides belt and present results from geochemical and Sr-Nd isotopic studies as well as zircon U-Pb geochronology. The Tavdagi dacite that we investigate in this study is exposed as round or ellipsoidal shaped bodies, sills, and dikes in the southeastern part of the belt. Zircons in the dacite show euhedral crystal morphology with oscillatory zoning and high Th/U values (up to 1.69) typical of magmatic origin. Zircon LA-ICPMS analysis yielded a weighted mean 206Pb/238U age of 7.86 ± 0.15 Ma. SHRIMP analyses of zircons with typical magmatic zoning from another sample yielded a weighted mean 206Pb/238U age of 8.79 ± 0.19 Ma. Both ages are identical and constrain the timing of dacitic magmatism as late Miocene. The Miocene Tavdagi dacite shows adakitic affinity with high SiO2 (68.95-71.41 wt.%), Al2O3 (14.88-16.02 wt.%), Na2O (3.27-4.12 wt.%), Sr (331.4-462.1 ppm), Sr/Y (85-103.7), LaN/YbN (34.3-50.9) and low Y (3.2-5 ppm) values. Their initial 143Nd/144Nd (0.512723-0.512736) and 87Sr/86Sr (0.70484-0.70494) ratios are, respectively, lower and higher than those of normal oceanic crust. The geological, geochemical and isotopic data suggest that the adakitic magmatism was generated by partial melting of the mafic lower crust in the southeastern part of the eastern Pontide belt during the late Miocene. Based on the results presented in this study and a synthesis of the geological and tectonic information on the region, we propose that the entire northern edge of the eastern Pontides-Lesser Caucasus-Elbruz magmatic arc was an active continental margin during the Cenozoic. We identify a migration of the Cenozoic magmatism towards

La tipología urbanística alejandrina en la ciudad helenística

Directory of Open Access Journals (Sweden)

Joaquín Montero Múñiz

2000-01-01

Full Text Available En este artículo se realiza un acercamiento al urbanismo en la Antigüedad, y más en concreto al urbanismo regular aparecido en la antigua Grecia, que encuentra su máxima expresión y difusión con las conquistas territoriales de Alejandro Magno y, posteriormente, durante los reinos helenísticos. La planificación y la fundación de nuevas ciudades durante la época helenística no sólo es un agente motor de desarrollo económico, de control político-militar del territorio o de difusión cultural, sino un factor muy importante y profundo de la propaganda política regia que más tarde seguirán empleando los emperadores romanos.In this article is carried out an approach to the urbanism in the Antiquity, and specific to the planned urbanism in Ancient Greece, that finds its máximum expression and diffusion with Alexander's the Great territorial conquests and, later on, during the Hellenistic kingdoms. The planning and foundation of new cities during the Hellenistic era are not only a motor of economic development, political and military control of the territory or cultural diffusion, but a very important and deep factor of the royal political propaganda that will be used later by the Román emperors.

Kas olete mõelnud välismaal õpetamisele? / Edward Kess, Helen Oppar, Sergei Ptšjolkin ... [jt.

Index Scriptorium Estoniae

2011-01-01

Küsimusele vastavad Tallinna 37. keskkooli eesti keele ja kirjanduse õpetaja Edward Kess, Varstu keskkooli loodusainete õpetaja Helen Oppar, Tallinna Mustjõe gümnaasiumi füüsikaõpetaja Sergei Ptšjolkin, Sürgavere põhikooli muusikaõpetaja Helve Tähis, Nõo reaalgümnaasiumi inglise keele õpetaja Tiina Tuuling ning Rahumäe põhikooli matemaatikaõpetaja Kadri Hiob

Database for geologic maps of pyroclastic-flow and related deposits of the 1980 eruptions of Mount St. Helens, Washington

Science.gov (United States)

Furze, Andrew J.; Bard, Joseph A.; Robinson, Joel; Ramsey, David W.; Kuntz, Mel A.; Rowley, Peter D.; MacLeod, Norman S.

2017-10-31

This publication releases digital versions of the geologic maps in U.S. Geological Survey Miscellaneous Investigations Map 1950 (USGS I-1950), “Geologic maps of pyroclastic-flow and related deposits of the 1980 eruptions of Mount St. Helens, Washington” (Kuntz, Rowley, and MacLeod, 1990) (https://pubs.er.usgs.gov/publication/i1950). The 1980 Mount St. Helens eruptions on May 18, May 25, June 12, July 22, August 7, and October 16–18 produced pyroclastic-flow and related deposits. The distribution and morphology of these deposits, as determined from extensive field studies and examination of vertical aerial photographs, are shown on four maps in I-1950 (maps A–D) on two map sheets. Map A shows the May 18, May 25, and June 12 deposits; map B shows the July 22 deposits; map C shows the August 7 deposits; and map D shows the October 16–18 deposits. No digital geospatial versions of the geologic data were made available at the time of publication of the original maps. This data release consists of attributed vector features, data tables, and the cropped and georeferenced scans from which the features were digitized, in order to enable visualization and analysis of these data in GIS software. This data release enables users to digitally re-create the maps and description of map units of USGS I-1950; map sheet 1 includes text sections (Introduction, Physiography of Mount St. Helens at the time of the 1980 eruptions, Processes of the 1980 eruptions, Deposits of the 1980 eruptions, Limitations of the maps, Preparation of the maps, and References cited) and associated tables and figures that are not included in this data release.

Monitoring a restless volcano: The 2004 eruption of Mount St. Helens

Science.gov (United States)

Gardner, C.

2005-01-01

Although the precise course of volcanic activity is difficult to predict, volcanologists are pretty adept at interpreting volcanic signals from well-monitored volcanoes in order to make short-term forecasts. Various monitoring tools record effects to give us warning before eruptions, changes in eruptive behavior during eruptions, or signals that an eruption is ending. Foremost among these tools is seismic monitoring. The character, size, depth and rate of earthquakes are all important to the interpretation of what is happening belowground. The first inkling of renewed activity at Mount St. Helens began in the early hours of Sept. 23, when a seismic swarm - tens to hundreds of earthquakes over days to a week - began beneath the volcano. This article details the obervations made during the eruptive sequence.

The Myth of the Male Breadwinner: Women and Industrialization in the Caribbean by Helen I. Safa

OpenAIRE

Maurer, WM

1996-01-01

What are the implications of women's entry into the industrial workforce for their empowerment at the level of the household, workplace, and political arena? Helen Safa's book compares the experiences of women in Puerto Rico, the Dominican Republic, and Cuba to provide an insightful commentary on the gendered dimensions of the international division of labor. She documents changes in women's status as Puerto Rico and the Dominican Republic moved from import-substitution to e...

Multiplets: Their behavior and utility at dacitic and andesitic volcanic centers

Science.gov (United States)

Thelen, W.; Malone, S.; West, M.

2011-01-01

Multiplets, or groups of earthquakes with similar waveforms, are commonly observed at volcanoes, particularly those exhibiting unrest. Using triggered seismic data from the 1980-1986 Mount St. Helens (MSH) eruption, we have constructed a catalog of multiplet occurrence. Our analysis reveals that the occurrence of multiplets is related, at least in part, to the viscosity of the magma. We also constructed catalogs of multiplet occurrence using continuous seismic data from the 2004 eruption at MSH and 2007 eruption at Bezymianny Volcano, Russia. Prior to explosions at MSH in 2004 and Bezymianny in 2007, the multiplet proportion of total seismicity (MPTS) declined, while the average amplitudes and standard deviations of the average amplitude increased. The life spans of multiplets (time between the first and last event) were also shorter prior to explosions than during passive lava extrusion. Dome-forming eruptions that include a partially solidified plug, like MSH (1983-1986 and 2004-2008), often possess multiplets with longer life spans and MPTS values exceeding 50%. Conceptually, the relatively unstable environment prior to explosions is characterized by large and variable stress gradients brought about by rapidly changing overpressures within the conduit. We infer that such complex stress fields affect the number of concurrent families, MPTS, average amplitude, and standard deviation of the amplitude of the multiplets. We also argue that multiplet detection may be an important new monitoring tool for determining the timing of explosions and in forecasting the type of eruption.

Mount St. Helens ash and mud: Chemical properties and effects on germination and establishment of trees and browse plants.

Science.gov (United States)

M.A. Radwan; Dan L. Campbell

1981-01-01

Chemical properties of ash and mud from the 1980 volcanic eruption of Mount St. Helens and their effect on germination and seedling production of selected plants were studied. The volcanic materials were low in some important nutrients and cation exchange capacity, and they adversely affected seedling production. Catsear, a preferred wildlife browse, and lodgepole pine...

Kuidas rasketel hetkedel käitud, kellelt nõu küsid? / Erko Karing, Monika Peetson, Helen Sildna... [jt.

Index Scriptorium Estoniae

2010-01-01

Küsimusele vastavad Guvatraki reklaamibüroo juht Erko Karing, audiitor- ja finantsnõustamisfirma Deloitte vandeaudiitor Monika Peetson, muusikapeo Tallinn Music Week peakorraldaja ja ettevõtte MUsicCase omanik Helen Sildna, ETL-Baltic Groupi juhatuse esimees ja üks loojatest Krista Mulenok, Eesti Posti e-arvete operaatori eArvekeskus juht Marius Arrak ning firma Sailinvest omanik Jaanus Tamme

Attenuation and scattering tomography of the deep plumbing system of Mount St. Helens

Science.gov (United States)

De Siena, Luca; Thomas, Christine; Waite, Greg P.; Moran, Seth C.; Klemme, Stefan

2014-01-01

We present a combined 3-D P wave attenuation, 2-D S coda attenuation, and 3-D S coda scattering tomography model of fluid pathways, feeding systems, and sediments below Mount St. Helens (MSH) volcano between depths of 0 and 18 km. High-scattering and high-attenuation shallow anomalies are indicative of magma and fluid-rich zones within and below the volcanic edifice down to 6 km depth, where a high-scattering body outlines the top of deeper aseismic velocity anomalies. Both the volcanic edifice and these structures induce a combination of strong scattering and attenuation on any seismic wavefield, particularly those recorded on the northern and eastern flanks of the volcanic cone. North of the cone between depths of 0 and 10 km, a low-velocity, high-scattering, and high-attenuation north-south trending trough is attributed to thick piles of Tertiary marine sediments within the St. Helens Seismic Zone. A laterally extended 3-D scattering contrast at depths of 10 to 14 km is related to the boundary between upper and lower crust and caused in our interpretation by the large-scale interaction of the Siletz terrane with the Cascade arc crust. This contrast presents a low-scattering, 4–6 km2 “hole” under the northeastern flank of the volcano. We infer that this section represents the main path of magma ascent from depths greater than 6 km at MSH, with a small north-east shift in the lower plumbing system of the volcano. We conclude that combinations of different nonstandard tomographic methods, leading toward full-waveform tomography, represent the future of seismic volcano imaging.

Where Anthropology Meets History—A Review of "Tracing China: A Forty-Year Ethnographic Journey," by Helen F. Siu

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May Bo Ching

2017-09-01

Full Text Available Helen F. Siu. Tracing China: A Forty-Year Ethnographic Journey. Hong Kong: Hong Kong University Press, 2016. ISBN: 9789888083732. For years, Helen Siu tangoed with history and trekked the fields of South China. "Tracing China: A Forty-Year Ethnographic Journey"(Hong Kong University Press, 2016—a collection of Siu’s work published over the last twenty years—is not a grandiose showpiece splotched with a lot of paint and colors. Instead, she uses a 2B pencil to leave fine marks on wafer-thin parchment and smudges them ever so slightly, gradually letting the image emerge through the back of the page. If I have understood correctly, though plurality exists in the meanings of “trace,” Siu’s intention with the title Tracing China is less to track the history of China, and more to scrupulously examine every footstep she comes across, no matter how indistinct—to “look for plum blossoms in the snow,” as the Chinese saying goes. This saying might have inspired the Chinese version of the title of the collection, one that preserves a sense of graceful subtlety...

The mechanisms of fine particle generation and electrification during Mount St. Helens volcanic eruption

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Cheng, R. J.

1982-01-01

Microscopical investigation of volcanic ash collected from ground stations during Mount St. Helens eruptions reveal a distinctive bimodel size distribution with high concentrations of particle ranges at (1) 200-100 microns and (2) 20-0.1 microns. Close examination of individual particles shows that most larger ones are solidified magma particles of porous pumice with numerous gas bubbles in the interior and the smaller ones are all glassy fragments without any detectable gas bubbles. Elemental analysis demonstrates that the fine fragments all have a composition similar to that of the larger pumice particles. Laboratory experiments suggest that the formation of the fine fragments is by bursting of glassy bubbles from a partially solidified surface of a crystallizing molten magma particle. The production of gas bubbles is due to the release of absorbed gases in molten magma particles when solubility decreases during phase transition. Diffusion cloud chamber experiments strongly indicate that sub-micron volcanic fragments are highly hygroscopic and extremely active as cloud condensation nuclei. Ice crystals also are evidently formed on those fragments in a supercooled (-20 C) cloud chamber. It has been reported that charge generation from ocean volcanic eruptions is due to contact of molten lava with sea water. This seems to be insufficient to explain the observed rapid and intense lightning activities over Mount St. Helens eruptions. Therefore, a hypothesis is presented here that highly electrically charged fine solid fragments are ejected by bursting of gas bubbles from the surface of a crystallizing molten magma particles.

Helium sources to groundwater in active volcanic terrain, and implications for tritium-helium dating at Mount St. Helens

Energy Technology Data Exchange (ETDEWEB)

Gates, John B. [Department of Earth and Atmospheric Sciences, University of Nebraska-Lincoln, 217 Bessey Hall, Lincoln NE 68588 (United States)

2013-07-01

Groundwater helium sources and residence times were investigated using groundwater discharging from springs surrounding Mount St. Helens in the Cascades region of the United States. Significant contributions of mantle helium were found in all samples and are attributable to interaction between groundwater and magmatic gases. Bounding calculations for residence times were made on the basis of helium isotope mixing plots and historical tritium data. (authors)

Mount Saint Helens, Washington, USA, SRTM Perspective: Shaded Relief and Colored Height

Science.gov (United States)

2004-01-01

Mount Saint Helens is a prime example of how Earth's topographic form can greatly change even within our lifetimes. The mountain is one of several prominent volcanoes of the Cascade Range that stretches from British Columbia, Canada, southward through Washington, Oregon, and into northern California. Mount Adams (left background) and Mount Hood (right background) are also seen in this view, which was created entirely from elevation data produced by the Shuttle Radar Topography Mission. Prior to 1980, Mount Saint Helens had a shape roughly similar to other Cascade peaks, a tall, bold, irregular conic form that rose to 2950 meters (9677 feet). However, the explosive eruption of May 18, 1980, caused the upper 400 meters (1300 feet) of the mountain to collapse, slide, and spread northward, covering much of the adjacent terrain (lower left), leaving a crater atop the greatly shortened mountain. Subsequent eruptions built a volcanic dome within the crater, and the high rainfall of this area lead to substantial erosion of the poorly consolidated landslide material. Eruptions at Mount Saint Helens subsided in 1986, but renewed volcanic activity here and at other Cascade volcanoes is inevitable. Predicting such eruptions still presents challenges, but migration of magma within these volcanoes often produces distinctive seismic activity and minor but measurable topographic changes that can give warning of a potential eruption. Three visualization methods were combined to produce this image: shading of topographic slopes, color coding of topographic height, and then projection into a perspective view. The shade image was derived by computing topographic slope in the northeast-southwest (left to right) direction, so that northeast slopes appear bright and southwest slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations. The perspective view simulates the

O desejo na Grécia Helenística

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Zeferino Rocha

Full Text Available O presente trabalho é a terceira e última parte de uma pesquisa sobre “O desejo na Grécia Antiga”. Na primeira parte, reunimos as manifestações do desejo nos poemas épicos, líricos e trágicos, bem como nas máximas dos sete sábios e na doutrina dos filósofos pré-socráticos da Grécia Arcaica. Na segunda, apresentamos o essencial da sistematização teórica que, na Grécia Clássica, Sócrates, Platão e Aristóteles deram a essas primeiras manifestações do desejo. Nesta última parte, depois de lembrar a origem e as características da cultura helenística, vamos ver o que os epicuristas e os estóicos, no contexto de suas respectivas filosofias, disseram sobre o desejo no Jardim de Epicuro e no Pórtico Antigo de Zenão e Crísipo.

American Self-Fashioning in Helen Foster Snow's My China Years.

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Constance J. Post

2013-11-01

Full Text Available In My China Years: A Memoir, Helen Foster Snow draws upon her Puritan roots in fashioning an American self that affirms the power of an individual exemplary life, the ability to exercise free will amid struggle, an optimism borne of hope, and a way to represent failure and success. Self-fashioning, which Stephen Greenblatt attributes to the rise of an autonomous self in early modern Europe, is shaped by Snow as a distinctly American identity based on a secular Puritanism she found more congenial than the Puritanism of her ancestors on both sides of the Atlantic. The many resemblances noted by Snow between the Chinese Communist Army and seventeenth-century English Puritanism led her to interrogate Puritanism, both in its traditional form and its secularised variant. What emerges in the pages of My China Years is an attempt to fashion an American self by negotiating an old Puritanism with the new by way of a triangulation with China.

Geologic Map of the Helen Planitia Quadrangle (V-52), Venus

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Lopez, Ivan; Hansen, Vicki L.

2008-01-01

The Magellan spacecraft orbited Venus from August 10, 1990, until it plunged into the Venusian atmosphere on October 12, 1994. Magellan Mission objectives included (1) improving the knowledge of the geological processes, surface properties, and geologic history of Venus by analysis of surface radar characteristics, topography, and morphology and (2) improving the knowledge of the geophysics of Venus by analysis of Venusian gravity. The Helen Planitia quadrangle (V-52), located in the southern hemisphere of Venus between lat 25 deg S. and 50 deg S. and between long 240 deg E. and 270 deg E., covers approximately 8,000,000 km2. Regionally, the map area is located at the southern limit of an area of enhanced tectonomagmatic activity and extensional deformation, marked by a triangle that has highland apexes at Beta, Atla, and Themis Regiones (BAT anomaly) and is connected by the large extensional belts of Devana, Hecate, and Parga Chasmata. The BAT anomaly covers approximately 20 percent of the Venusian surface.

Directed blasts and blast-generated pyroclastic density currents: a comparison of the Bezymianny 1956, Mount St Helens 1980, and Soufrière Hills, Montserrat 1997 eruptions and deposits

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Belousov, Alexander; Voight, Barry; Belousova, Marina

2007-01-01

We compare eruptive dynamics, effects and deposits of the Bezymianny 1956 (BZ), Mount St Helens 1980 (MSH), and Soufrière Hills volcano, Montserrat 1997 (SHV) eruptions, the key events of which included powerful directed blasts. Each blast subsequently generated a high-energy stratified pyroclastic density current (PDC) with a high speed at onset. The blasts were triggered by rapid unloading of an extruding or intruding shallow magma body (lava dome and/or cryptodome) of andesitic or dacitic composition. The unloading was caused by sector failures of the volcanic edifices, with respective volumes for BZ, MSH, and SHV c. 0.5, 2.5, and 0.05 km3 . The blasts devastated approximately elliptical areas, axial directions of which coincided with the directions of sector failures. We separate the transient directed blast phenomenon into three main parts, the burst phase, the collapse phase, and the PDC phase. In the burst phase the pressurized mixture is driven by initial kinetic energy and expands rapidly into the atmosphere, with much of the expansion having an initially lateral component. The erupted material fails to mix with sufficient air to form a buoyant column, but in the collapse phase, falls beyond the source as an inclined fountain, and thereafter generates a PDC moving parallel to the ground surface. It is possible for the burst phase to comprise an overpressured jet, which requires injection of momentum from an orifice; however some exploding sources may have different geometry and a jet is not necessarily formed. A major unresolved question is whether the preponderance of strong damage observed in the volcanic blasts should be attributed to shock waves within an overpressured jet, or alternatively to dynamic pressures and shocks within the energetic collapse and PDC phases. Internal shock structures related to unsteady flow and compressibility effects can occur in each phase. We withhold judgment about published shock models as a primary explanation for the

Redox pioneer:Professor Christine Helen Foyer.

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Del Río, Luis A

2011-10-15

Dr. Christine Foyer (B.Sc. 1974; Ph.D. 1977) is recognized here as a Redox Pioneer because she has published an article on redox biology that has been cited more than 1000 times, 4 other articles that have been cited more than 500 times, and a further 32 articles that have been each cited more than 100 times. During her Ph.D. at the Kings College, University of London, United Kingdom, Dr. Foyer discovered that ascorbate and glutathione and enzymes linking NADPH, glutathione, and ascorbate are localized in isolated chloroplast preparations. These observations pioneered the discovery of the ascorbate-glutathione cycle, now known as Foyer-Halliwell-Asada pathway after the names of the three major contributors, a crucial mechanism for H(2)O(2) metabolism in both animals and plants. Dr. Foyer has made a very significant contribution to our current understanding of the crucial roles of ascorbate and glutathione in redox biology, particularly in relation to photosynthesis, respiration, and chloroplast and mitochondrial redox signaling networks. "My view is that science…is compulsive and you have to keep with it all the time and not get despondent when things do not work well. Being passionate about science is what carries you through the hard times so that it isn't so much work, as a hobby that you do for a living. It is the thrill of achieving a better understanding and finding real pleasure in putting new ideas together, explaining data and passing on knowledge that keeps you going no matter what!" --Prof. Christine Helen Foyer.

Helen Flanders Dunbar, John Dewey, and clinical pragmatism: reflections on method in psychosomatic medicine and bioethics.

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Hart, Curtis W

2002-01-01

This article outlines the method utilized by physicians and major figures in the founding of Clinical Pastoral Education, Helen Flanders Dunbar, in her work of 1943, Psychosomatic Diagnosis, and relates it to the currently evolving approach in bioethics known as clinical pragmatism. It assesses Dewey's influence on both Dunbar in psychosomatic medicine and clinical pragmatism in bioethics, and illustrates the breadth of influence of the school of philosophical thought known as pragmatism with which Dewey's name and those of William James and Charles Sanders Pierce are most often identified.

Separating volcanic deformation and atmospheric signals at Mount St. Helens using Persistent Scatterer InSAR

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Welch, Mark D.; Schmidt, David A.

2017-09-01

Over the past two decades, GPS and leveling surveys have recorded cycles of inflation and deflation associated with dome building eruptions at Mount St. Helens. Due to spatial and temporal limitations of the data, it remains unknown whether any deformation occurred prior to the most recent eruption of 2004, information which could help anticipate future eruptions. Interferometric Synthetic Aperture Radar (InSAR), which boasts fine spatial resolution over large areas, has the potential to resolve pre-eruptive deformation that may have occurred, but eluded detection by campaign GPS surveys because it was localized to the edifice or crater. Traditional InSAR methods are challenging to apply in the Cascades volcanic arc because of a combination of environmental factors, and past attempts to observe deformation at Mount St. Helens were unable to make reliable observations in the crater or on much of the edifice. In this study, Persistent Scatterer InSAR, known to mitigate issues of decorrelation caused by environmental factors, is applied to four SAR data sets in an attempt to resolve localized sources of deformation on the volcano between 1995 and 2010. Many interferograms are strongly influenced by phase delay from atmospheric water vapor and require correction, evidenced by a correlation between phase and topography. To assess the bias imposed by the atmosphere, we perform sensitivity tests on a suite of atmospheric correction techniques, including several that rely on the correlation of phase delay to elevation, and explore approaches that directly estimate phase delay using the ERA-Interim and NARR climate reanalysis data sets. We find that different correction methods produce velocities on the edifice of Mount St. Helens that differ by up to 1 cm/yr due to variability in how atmospheric artifacts are treated in individual interferograms. Additionally, simple phase-based techniques run the risk of minimizing any surface deformation signals that may themselves be

Water in melt inclusions from phenocrysts of dacite pumice of the Vetrovoy Isthmus (Iturup Island, Southern Kuriles)

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Kotov, A. A.; Smirnov, S. Z.; Maksimovich, I. A.; Plechov, P. Yu; Chertkova, N. V.; Befus, A. I.

2017-12-01

This work is devoted to the study of one of the largest caldera eruptions of the Kurile-Kamchatka island-arc system that occurred on the island of Iturup. The object of investigation of this work are phenocrysts of quartz and plagioclase from dacite pumice of the Isthmus of the Isthmus, which is located on the island of Iturup. The purpose of this work is to determine the water content in the melts that participated in the caldera eruption of the Vetrovoy Isthmus and the patterns of their changes during the crystallization of magma. In the course of the work, the following were carried out: 1) adaptation and calibration of the Raman spectroscopy method for determining water in rhyolite melt’s inclusions glasses in quartz and plagioclase from pumice stone; 2) determination of composition and estimation of water content in melt inclusions in quartz and plagioclase according to x-ray spectral analysis; 3) establishment of the regularities of the change in the water content during the evolution of the magmatic melt; 4) evaluation of fluid pressure by comparison with experimental data

Trophic Interactions during Primary Succession: Herbivores Slow a Plant Reinvasion at Mount St. Helens.

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Fagan, William F; Bishop, John G

2000-02-01

Lupines (Lupinus lepidus var. lobbii), the earliest plant colonists of primary successional habitats at Mount St. Helens, were expected to strongly affect successional trajectories through facilitative effects. However, their effects remain localized because initially high rates of reinvasive spread were short lived, despite widespread habitat availability. We experimentally tested whether insect herbivores, by reducing plant growth and fecundity at the edge of the expanding lupine population, could curtail the rate of reinvasion and whether those herbivores had comparable impacts in the older, more successionally advanced core region. We found that removing insect herbivores increased both the areal growth of individual lupine plants and the production of new plants in the edge region, thereby accelerating the lupine's intrinsic rate of increase at the front of the lupine reinvasion. We found no such impacts of herbivory in the core region, where low plant quality or a complex of recently arrived natural enemies may hold herbivores in check. In the context of invasion theory, herbivore-mediated decreases in lupine population growth rate in the edge region translate into decreased rates of lupine spread, which we quantify here using diffusion models. In the Mount St. Helens system, decreased rate of lupine reinvasion will result in reductions in rates of soil formation, nitrogen input, and entrapment of seeds and detritus that are likely to postpone or alter trajectories of primary succession. If the type of spatial subtleties in herbivore effects we found here are common, with herbivory focused on the edge of an expanding plant population and suppressed or ineffective in the larger, denser central region (where the plants might be more readily noticed and studied), then insect herbivores may have stronger impacts on the dynamics of primary succession and plant invasions than previously recognized.

Helen Kim as New Woman and Collaborator: A Comprehensive Assessment of Korean Collaboration under Japanese Colonial Rule

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AhRan Ellie Bae

2017-02-01

Full Text Available Although almost seventy years has passed since Korea's liberation from Japanese rule, the issue of collaboration still haunts Korea today. Attempts to resolve this issue have tended to focus attention on the traitorous actions of "collaborators" without considering the gray areas that surround their actions such as the circumstances that influenced the accused to commit their alleged traitorous acts and the intentions that drove their decisions. Helen Kim, as a "new woman" and an educator, valued the necessity of providing education for women. Yet, her efforts to realize this goal, to the contrary, forced her into actions that would later be used to construct a reputation as a Japanese collaborator. Korea's nationalist historiography has a tendency to polarize this issue by categorizing a "collaborator" as either a traitor or a patriot. However, when we take a closer look at these collaborators' lives, we discover that most collaboration happened in gray areas where it is often difficult to clearly draw a line between treason and collaboration. Helen Kim's case suggests that the issue of collaboration cannot be fully explained by nationalist historiography's framework and we must give attention to these gray areas. Through her story I hope to complicate the issue of collaboration by raising questions that address the gray areas that surround the actions of "collaborators." In doing so, I hope to challenge the nationalist historiography's propensity to oversimplify this issue and present a more nuanced understanding of it.

Anthropology in a postcolonial colony: Helen I. Safa's contribution to Puerto Rican ethnography.

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Duany, Jorge

2010-01-01

This article assesses Helen I. Safa's legacy to anthropological thought in Puerto Rico. The first part of the article locates Safa's research on the Island within a long tradition of fieldwork by U.S. scholars since the early twentieth century. More recent research, conducted mostly by Puerto Rican women anthropologists and other social scientists, has expanded upon Safa's insights on gender and work. The second part of the essay analyzes Safa's major empirical work, The Urban Poor of Puerto Rico: A Study in Development and Inequality. Above all, this book helped overcome the theoretical impasse over the culture of poverty that characterized much of urban anthropology during the 1960s and 1970s. The article concludes with an appraisal of the relevance of Safa's work for the ethnography of contemporary Puerto Rico.

Vanemate töötamine välismaal - kuidas see mõjutab lapse elu : laste ja spetsialistide tõlgendused / Helen Pärna, Karmen Lai, Taimi Tulva

Index Scriptorium Estoniae

Pärna, Helen, 1983-

2008-01-01

Artikkel tugineb Helen Pärna magistriuurimusele. Ülevaade uurimustulemustest, mis puudutavad välismaale tööle läinud lapsevanemate lapse toimetulekut argieluga ning arutletakse selle üle, kuidas lapse lahusolek vanematest võib mõjutada lapse ja vanema vahelisi suhteid

Effects of slope on the formation of dunes in dilute, turbulent pyroclastic currents: May 18th, 1980 Mt. St. Helens eruption

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Bendana, Sylvana; Brand, Brittany D.; Self, Stephen

2014-05-01

The flanks of Mt St Helens volcano (MSH) are draped with thin, cross-stratified and stratified pyroclastic density current (PDC) deposits. These are known as the proximal bedded deposits produced during the May 18th, 1980 eruption of MSH. While the concentrated portions of the afternoon PDCs followed deep topographic drainages down the steep flanks of the volcano, the dilute overriding cloud partially decoupled to develop fully dilute, turbulent PDCs on the flanks of the volcano (Beeson, D.L. 1988. Proximal Flank Facies of the May 18, 1980 Ignimbrite: Mt. St. Helens, Washington.). The deposits along the flank thus vary greatly from those found in the pumice plain, which are generally thick, massive, poorly-sorted, block-rich deposits associated with the more concentrated portions of the flow (Brand et al, accepted. Dynamics of pyroclastic density currents: Conditions that promote substrate erosion and self-channelization - Mount St Helens, Washington (USA). JVGR). We explore the influence of topography on the formation of these dilute currents and influence of slope on the currents transport and depositional mechanisms. The deposits on steeper slopes (>15°) are fines depleted relative to the proximal bedded deposits on shallower slopes (<15°). Bedform amplitude and wavelength increase with increasing slope, as does the occurrence of regressive dunes. Increasing slope causes an increase in flow velocity and thus an increase in flow turbulence. The fines depleted deposits suggest that fine ash elutriation is more efficient in flows with stronger turbulence. The longer wavelength and amplitudes suggest that bedform morphology is directly related to flow velocity, an important finding since the controls on bedform wavelength and amplitude in density stratified flows remains poorly constrained. The occurrence of regressive dunes, often interpreted as high flow-regime bedforms, on steeper slopes relative to progressive dunes on shallower slopes further attests to the

Mineral dust transport toward Hurricane Helene (2006)

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Schwendike, Juliane; Jones, Sarah C.; Vogel, Bernhard; Vogel, Heike

2016-05-01

This study investigates the transport of mineral dust from its source regions in West Africa toward the developing tropical cyclone Helene (2006) and diagnoses the resulting properties of the air influencing the tropical cyclonegenesis. The model system COSMO-ART (Consortium for Small-Scale Modelling-Aerosols and Reactive Trace gases) in which the emission and transport of mineral dust as well as the radiation feedback are taken into account, was used. The emission of mineral dust between 9 and 14 September 2006 occurred in association with the relatively strong monsoon flow and northeasterly trade winds, with gust fronts of convective systems over land, and with the Atlantic inflow. Additionally, increased surface wind speed was linked to orographical effects at the Algerian Mountains, Atlas Mountains, and the Hoggar. The dust, as part of the Saharan air layer, is transported at low levels by the monsoon flow, the Harmattan, the northeasterly trade winds, and the monsoon trough, and is transported upward in the convergence zone between Harmattan and monsoon flow, in the baroclinic zone along the West African coastline, and by convection. At around 700 hPa the dust is transported by the African easterly jet. Dry and dust-free air is found to the north-northwest of the developing tropical depression due to descent in an anticyclone. Based on the model data, it was possible to distinguish between dry (from the anticyclone), dry and dusty (from the Harmattan and northeasterly trade winds), and dusty and moist air (from the monsoon flow and in the tropical depression due to convection).

Measurements of SO2 in the Mount St. Helens debris

International Nuclear Information System (INIS)

Kerr, J.B.; Evans, F.J.; Mateer, C.L.

1982-01-01

Routine measurements of ozone and SO 2 are made with the Dobson and Brewer spectrophotometers at the Atmospheric Environment Service in Downsview Ontario. On May 20 and 21, 1980, large values of column SO 2 were observed with both spectrophotometers at the time of passage of the Mount St. Helens debris. Enhanced SO 2 values were first observed at 1800Z on May 20. The maximum column amount of SO 2 measured was 0.06 cm at 2200 Z. On May 21, SO 2 values slowly decreased from 0.03 cm at 1100 Z cm to 0.01 cm at 2000Z. Typical SO 2 amounts due to pollution at the Downsview site are approximately 0.003 to 0.005 cm. At the same time of maximum SO 2 enhancement, both Dobson and Brewer spectrophotometers measured a 0.040 cm decrease of total ozone. It is not clear whether the decrease of total ozone was caused by the volcanic cloud or natural ozone variability. Air mass trajectories indicate that the altitude of the debris cloud, which passed over Downsview at the time, was between 10 km and 12 km

Critical Terrorism Studies Since 11 September 2001: What Has Been Learned? Edited by David Miller, Jessie Blackbourn, Rani Dhanda and Helen Dexter. New York, NT: Routledge, 2014.

Directory of Open Access Journals (Sweden)

Mark Roberts

2014-04-01

Full Text Available Critical Terrorism Studies Since 11 September 2001: What Has Been Learned? Edited by David Miller, Jessie Blackbourn, Rani Dhanda and Helen Dexter. New York, NT: Routledge, 2014. ISBN 978-0-415-83852-8. Graphs. Tables. Sources cited. Index. Pp. viii, 144. $137.75.

Rheology of arc dacite lavas: experimental determination at low strain rates

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Avard, Geoffroy; Whittington, Alan G.

2012-07-01

Andesitic-dacitic volcanoes exhibit a large variety of eruption styles, including explosive eruptions, endogenous and exogenous dome growth, and kilometer-long lava flows. The rheology of these lavas can be investigated through field observations of flow and dome morphology, but this approach integrates the properties of lava over a wide range of temperatures. Another approach is through laboratory experiments; however, previous studies have used higher shear stresses and strain rates than are appropriate to lava flows. We measured the apparent viscosity of several lavas from Santiaguito and Bezymianny volcanoes by uniaxial compression, between 1,109 and 1,315 K, at low shear stress (0.085 to 0.42 MPa), low strain rate (between 1.1 × 10-8 and 1.9 × 10-5 s-1), and up to 43.7 % total deformation. The results show a strong variability of the apparent viscosity between different samples, which can be ascribed to differences in initial porosity and crystallinity. Deformation occurs primarily by compaction, with some cracking and/or vesicle coalescence. Our experiments yield apparent viscosities more than 1 order of magnitude lower than predicted by models based on experiments at higher strain rates. At lava flow conditions, no evidence of a yield strength is observed, and the apparent viscosity is best approached by a strain rate- and temperature-dependent power law equation. The best fit for Santiaguito lava, for temperatures between 1,164 and 1,226 K and strain rates lower than 1.8 × 10-4 s-1, is log {η_{{app}}} = - 0.738 + 9.24 × {10^3}{/}T(K) - 0.654 \\cdot log dot{\\varepsilon } where η app is apparent viscosity and dot{\\varepsilon } is strain rate. This equation also reproduced 45 data for a sample from Bezymianny with a root mean square deviation of 0.19 log unit Pa s. Applying the rheological model to lava flow conditions at Santiaguito yields calculated apparent viscosities that are in reasonable agreement with field observations and suggests that

Counting, accounting, and accountability: Helen Verran's relational empiricism.

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Kenney, Martha

2015-10-01

Helen Verran uses the term 'relational empiricism' to describe situated empirical inquiry that is attentive to the relations that constitute its objects of study, including the investigator's own practices. Relational empiricism draws on and reconfigures Science and Technology Studies' traditional concerns with reflexivity and relationality, casting empirical inquiry as an important and non-innocent world-making practice. Through a reading of Verran's postcolonial projects in Nigeria and Australia, this article develops a concept of empirical and political 'accountability' to complement her relational empiricism. In Science and an African Logic, Verran provides accounts of the relations that materialize her empirical objects. These accounts work to decompose her original objects, generating new objects that are more promising for the specific postcolonial contexts of her work. The process of decomposition is part of remaining accountable for her research methods and accountable to the worlds she is working in and writing about. This is a practice of narrating relations and learning to tell better technoscientific stories. What counts as better, however, is not given, but is always contextual and at stake. In this way, Verran acts not as participant-observer, but as participant-storyteller, telling stories to facilitate epistemic flourishing within and as part of a historically located community of practice. The understanding of accountability that emerges from this discussion is designed as a contribution, both practical and evocative, to the theoretical toolkit of Science and Technology Studies scholars who are interested in thinking concretely about how we can be more accountable to the worlds we study.

Volcano dome dynamics at Mount St. Helens: Deformation and intermittent subsidence monitored by seismicity and camera imagery pixel offsets

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Salzer, Jacqueline T.; Thelen, Weston A.; James, Mike R.; Walter, Thomas R.; Moran, Seth C.; Denlinger, Roger P.

2016-01-01

The surface deformation field measured at volcanic domes provides insights into the effects of magmatic processes, gravity- and gas-driven processes, and the development and distribution of internal dome structures. Here we study short-term dome deformation associated with earthquakes at Mount St. Helens, recorded by a permanent optical camera and seismic monitoring network. We use Digital Image Correlation (DIC) to compute the displacement field between successive images and compare the results to the occurrence and characteristics of seismic events during a 6 week period of dome growth in 2006. The results reveal that dome growth at Mount St. Helens was repeatedly interrupted by short-term meter-scale downward displacements at the dome surface, which were associated in time with low-frequency, large-magnitude seismic events followed by a tremor-like signal. The tremor was only recorded by the seismic stations closest to the dome. We find a correlation between the magnitudes of the camera-derived displacements and the spectral amplitudes of the associated tremor. We use the DIC results from two cameras and a high-resolution topographic model to derive full 3-D displacement maps, which reveals internal dome structures and the effect of the seismic activity on daily surface velocities. We postulate that the tremor is recording the gravity-driven response of the upper dome due to mechanical collapse or depressurization and fault-controlled slumping. Our results highlight the different scales and structural expressions during growth and disintegration of lava domes and the relationships between seismic and deformation signals.

Evolving magma storage conditions beneath Mount St. Helens inferred from chemical variations in melt inclusions from the 1980-1986 and current (2004-2006) eruptions: Chapter 33 in A volcano rekindled: the renewed eruption of Mount St. Helens, 2004-2006

Science.gov (United States)

Blundy, Jon; Cashman, Katharine V.; Berlo, Kim; Sherrod, David R.; Scott, William E.; Stauffer, Peter H.

2008-01-01

Major element, trace element, and volatile concentrations in 187 glassy melt inclusions and 25 groundmass glasses from the 1980-86 eruption of Mount St. Helens are presented, together with 103 analyses of touching FE-Ti oxide pairs from the same samples. These data are used to evaluate the temporal evolution of the magmatic plumbing system beneath the volcano during 1980-86 and so provide a framework in which to interpret analyses of melt inclusions from the current (2004-2006) eruption. Major and trace element concentrations of all melt inclusions lie at the high SiO2 end of the data array defined by eruptive products of the late Quaternary age from Mount St. Helens. For several major and trace elements, the glasses define a trend that is oblique to the whole-rock trend, indicating that different mineral assemblages were responsible for the two trends. The whole-rock trend can be ascribed to differentiation of hydrous basaltic parents in a deep-seated magma reservoir, probably at depths great enough to stabilize garnet. In contrast, the glass trends were generated by closed-system crystallization of the phenocryst and microlite mineral assemblages at low pressures. The dissolved H2O content of the melt inclusions from 1980-86, as measured by the ion microprobe, ranges from 0 to 6.7 wt. percent, with the highest values obtained from the plinian phase of May 18, 1980. Water contents decrease with increasing SiO2, consistent with decompression-driven crystallization. Preliminary data for dissolved CO2 in melt inclusions from the May 18 plinian phase from August 7, 1980, indicate that XH2O in a vapor phase was approximately constant at 0.80, irrespective of H2O content, suggestive of closed-system degassing with a high bubble fraction or gas streaming through the subvolcanic system. Temperature and f

Helen Sullivan, The Communal Mind and the Master Artifice, Athènes, Stochastis Editions, 2009-2010, 725 pages.

Directory of Open Access Journals (Sweden)

Dorval Brunelle

2011-11-01

Full Text Available La petite histoire de la publication de ce gros livre, tout comme celle de son auteur d’ailleurs, est assez inusitée et mérite certainement le detour avant d’entrer dans le vif du sujet. Le contexteHelen Sullivan était historienne et sociologue; elle est née aux États-Unis en 1906 et elle est morte en Grèce, en 1992. Diplomée de la Cornell University, elle a été l’une des 15 assistant editors de la vaste Encyclopaedia of Social Sciences publiée sous la direction de Edwin R. A. Seligman à comp...

Urbanistid ja keskkonnaeksperdid: iga muudatuse eest Reidi tee projektis oleme pidanud võitlema / Helen Sooväli-Sepping, Kristi Grišakov, Mari Jüssi ; intervjueerinud Mari Peegel ; kommenteerinud Taavi Aas

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Sooväli-Sepping, Helen, 1974-

2016-01-01

TLÜ keskkonnakorralduse professor ja linnakorralduse õppekava juht Helen Sooväli-Sepping, TTÜ maastikuarhitektuuri õppekava juht ja linnaplaneerija-urbanist Kristi Grišakov ning Stockholmi keskkonnainstituudi Tallinna keskuse liikuvus- ja keskkonnaekspert Mari Jüssi kinnitavad, et Reidi tee projekt ei ole endiselt inimsõbralik

Chronology, morphology and stratigraphy of pumiceous pyroclastic-flow (ignimbrite) deposits from the eruption of Mount St. Helens on 18 May 1983

Science.gov (United States)

Criswell, C. W.; Elston, W. E.

1984-01-01

Between 1217 and 1620 hours (PDT), on May 18, 1980, the magmatic eruption column of Mount St. Helens formed an ash fountain and pyroclastic flows dominated the eruption process over tephra ejection. Eurption-rate pulsations generally increased to a maximum at 1600 to 1700 hrs. After 1620 hrs, the eruption assumed an open-vent discharge with strong, vertical ejection of tephra. Relative eruption rates (relative mass flux rates) of the pyroclastic flows were determined by correlating sequential photographs and SLAR images, obtained during the eruption, with stratigraphy and surface morphology of the deposits.

Landscape Response to the 1980 Eruption of Mount St. Helens: Using Historical Aerial Photography to Measure Surface Change

Science.gov (United States)

Sweeney, K.; Major, J. J.

2016-12-01

Advances in structure-from-motion (SfM) photogrammetry and point cloud comparison have fueled a proliferation of studies using modern imagery to monitor geomorphic change. These techniques also have obvious applications for reconstructing historical landscapes from vertical aerial imagery, but known challenges include insufficient photo overlap, systematic "doming" induced by photo-spacing regularity, missing metadata, and lack of ground control. Aerial imagery of landscape change in the North Fork Toutle River (NFTR) following the 1980 eruption of Mount St. Helens is a prime dataset to refine methodologies. In particular, (1) 14-μm film scans are available for 1:9600 images at 4-month intervals from 1980 - 1986, (2) the large magnitude of landscape change swamps systematic error and noise, and (3) stable areas (primary deposit features, roads, etc.) provide targets for both ground control and matching to modern lidar. Using AgiSoft PhotoScan, we create digital surface models from the NFTR imagery and examine how common steps in SfM workflows affect results. Tests of scan quality show high-resolution, professional film scans are superior to office scans of paper prints, reducing spurious points related to scan infidelity and image damage. We confirm earlier findings that cropping and rotating images improves point matching and the final surface model produced by the SfM algorithm. We demonstrate how the iterative closest point algorithm, implemented in CloudCompare and using modern lidar as a reference dataset, can serve as an adequate substitute for absolute ground control. Elevation difference maps derived from our surface models of Mount St. Helens show patterns consistent with field observations, including channel avulsion and migration, though systematic errors remain. We suggest that subtracting an empirical function fit to the long-wavelength topographic signal may be one avenue for correcting systematic error in similar datasets.

The role of mycorrhizal fungi and microsites in primary succession on Mount St. Helens.

Science.gov (United States)

Titus, J; Del Moral, R

1998-03-01

This study was designed to examine the role of vesicular-arbuscular mycorrhizae (VAM) and microsites on the growth of pioneer species. Flat, rill, near-rock, and dead lupine microsites were created in plots in barren areas of the Pumice Plain of Mount St. Helens. VAM propagules were added to the soil in half of the plots. Six pioneer species were planted into both VAM and non-VAM inoculated microsites. Plants in dead lupine microsites were greater in biomass than those in flat, rill, and near-rock microsites. Significant effects of VAM on plant biomass did not occur. Microsites continue to be important to plant colonization on the Pumice Plain, but VAM do not yet appear to play an important role. This may be due to limited nutrient availability and the facultatively mycotrophic nature of the colonizing plant species. It is unlikely that VAM play an important role in successional processes in newly emplaced nutrient-poor surfaces.

Physical and chemical characteristics of Mt. St. Helens airborne debris

International Nuclear Information System (INIS)

Sedlacek, W.A.; Heiken, G.H.; Mroz, E.J.; Gladney, E.S.; Perrin, D.R.; Leifer, R.; Fisenne, I.; Hinchliffe, L.; Chuan, R.L.

1980-01-01

Tephra and aerosols from the May 18, 1980 eruption of Mt. St. Helens, Washington were sampled in the lower stratosphere with a WB-57F aircraft. The main body of the plume was intercepted over western Kansas on May 20, 48 hours after the eruption, at an altitude of 15.2 km. Concentrations on filter samples were 26 ng of SO 4 /g of air and 579 ng of ash/g of air. Angular glass pyroclasts ranged in size from 0.5 to 10 μm, with a mean grain size of 2 μm. Samples collected at altitudes of 16.7 and 12.5 km had only traces of SO 4 and ash. A second flight was flown, 72 hours after the eruption, on May 21. From north Texas to central Wyoming, at an altitude of 15.2 km, 4 /g of air were sampled. At an altitude of 18.3 km, from central Wyoming to NW New Mexico, the plume density and character were variable. Glassy pyroclasts similar to those sampled on the first flight range in size from 0.5 to 4 μm dia. Trace element analysis revealed some volatile element enrichment, but far less than previously observed in the plume from St. Augustine Volcano, 1976. Values of 210 Po/ 210 Pb were 0.7 to 1.32 comparable to the secular equilibrium value of 1.0 and far less than ratios previously reported by Lambert

Sediment erosion and delivery from Toutle River basin after the 1980 eruption of Mount St. Helens: A 30-year perspective

Science.gov (United States)

Major, Jon J.; Mosbrucker, Adam; Spicer, Kurt R.; Crisafulli, Charles; Dale, V.

2018-01-01

Exceptional sediment yields persist in Toutle River valley more than 30 years after the major 1980 eruption of Mount St. Helens. Differencing of decadal-scale digital elevation models shows the elevated load comes largely from persistent lateral channel erosion across the debris-avalanche deposit. Since the mid-1980s, rates of channel-bed-elevation change have diminished, and magnitudes of lateral erosion have outpaced those of channel incision. A digital elevation model of difference from 1999 to 2009 shows erosion across the debris-avalanche deposit is more spatially distributed compared to a model from 1987 to 1999, in which erosion was strongly focused along specific reaches of the channel.

Human radiation studies: Remembering the early years. Oral history of Oncologist Helen Vodopick, M.D., December 28, 1994

International Nuclear Information System (INIS)

1995-08-01

This report is a transcript of an interview with Dr. Helen Vodopick by representatives of the US DOE Office of Human Radiation Experiments. Dr. Vodopick was chosen for this interview because of her involvement with the Oak Ridge Institute of Nuclear Studies (ORINS) and Oak Ridge Associated Universities (ORAU) experimental cancer-therapy program involving total-body irradiation. After a short biographical sketch Dr. Vodopick relates her remembrances of the Medium-Exposure-Rate Total Body Irradiator (METBI), ORINS radioisotope tracer studies, treatment of cancer patients with the METBI, radiation treatment for leukemia patients, bone marrow treatment of leukemia, the Low-Exposure-Rate Total Body Irradiation (LETBI), treatment of radiation accident victims at ORAU, research with radioactive phosphorus and sulfur, and public opinion issues

Inpatient management of borderline personality disorder at Helen Joseph Hospital, Johannesburg

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Laila Paruk

2016-06-01

Full Text Available Objective: The aim of this report was to establish a profile of patients with borderline personality disorder (BPD admitted to the acute inpatient psychiatric assessment unit at the Helen Joseph Hospital, in Johannesburg, over the course of 1 year. Methods: A retrospective record review was conducted to investigate the prevalence, demographics, reasons for admission, treatment, length of stay and follow-up of a group of inpatients during 2010 with a diagnosis of BPD, based on DSM-IV-TR diagnostic criteria, allocated on discharge. Results: Considering evidence retrospectively, the quality of the BPD diagnosis allocated appeared adequate. Statistical analysis revealed findings mainly in keeping with other reports, for example, that patients with BPD are above-average users of resources who make significantly more use of emergency services and that they generally do not adhere well to their scheduled outpatient follow-up arrangements. The longer average length of inpatient stay of this group with BPD, however, exceeded the typically brief period generally recommended for acute inpatient containment and emergency intervention. Conclusion: Implementation of targeted prevention and early intervention strategies, based on systematised programmes such as dialectical behavioural therapy and mentalisation based therapy, may be useful in addressing these problems experienced with integrating the in- and outpatient management of BPD. Keywords: Borderline personality; inpatient; acute

Temporal changes in stress preceding the 2004-2008 eruption of Mount St. Helens, Washington

Science.gov (United States)

Lehto, H.L.; Roman, D.C.; Moran, S.C.

2010-01-01

The 2004-2008 eruption of Mount St. Helens (MSH), Washington, was preceded by a swarm of shallow volcano-tectonic earthquakes (VTs) that began on September 23, 2004. We calculated locations and fault-plane solutions (FPS) for shallow VTs recorded during a background period (January 1999 to July 2004) and during the early vent-clearing phase (September 23 to 29, 2004) of the 2004-2008 eruption. FPS show normal and strike-slip faulting during the background period and on September 23; strike-slip and reverse faulting on September 24; and a mixture of strike-slip, reverse, and normal faulting on September 25-29. The orientation of ??1 beneath MSH, as estimated from stress tensor inversions, was found to be sub-horizontal for all periods and oriented NE-SW during the background period, NW-SE on September 24, and NE-SW on September 25-29. We suggest that the ephemeral ~90?? change in ??1 orientation was due to intrusion and inflation of a NE-SW-oriented dike in the shallow crust prior to the eruption onset. ?? 2010 Elsevier B.V.

The 12.1 ka Middle Toluca Pumice: A dacitic Plinian subplinian eruption of Nevado de Toluca in Central Mexico

Science.gov (United States)

Arce, J. L.; Cervantes, K. E.; Macías, J. L.; Mora, J. C.

2005-10-01

The Nevado de Toluca volcano erupted explosively approximately 12.1 ka ago, producing a Plinian-subplinian eruption that deposited the Middle Toluca Pumice (MTP). The MTP consists of white and gray juvenile pumice, gray dense juvenile lapilli, and red altered lithic lapilli. The pumice is dacitic (63.54-65.06 wt.% SiO 2) with phenocrysts of plagioclase > orthopyroxene > hornblende ± ilmenite and titanomagnetite, and biotite xenocrysts set in a groundmass of rhyolitic glass (70-71 wt.% SiO 2). The MTP has a dispersal axis to the ESE covering an area of 92 km 2, with a minimum volume of 1.8 km 3 (DRE). Stratigraphic relations, grain size, componentry, and vesicularity analyses suggest that the eruption occurred in five major phases: (1) an opening magmatic phase that generated a 20-km-high Plinian column dispersed to the SE; (2) a hydromagmatic explosion followed with the establishment of a subplinian eruptive column (18-19 km high) dispersed tephra to the SE and gradually waned; (3) hydromagmatic explosions emplaced dilute pyroclastic density currents followed by the formation of an eruptive column of unknown height; (4) immediately after, a new magmatic explosion established another eruptive column; and (5) the collapse of the latter column generated two pumiceous pyroclastic density currents that were fully dilute proximally, but transformed into two granular-fluid pyroclastic currents that traveled 19 km from the source.

Ambient noise tomography across Mount St. Helens using a dense seismic array

KAUST Repository

Wang, Yadong

2017-05-08

We investigated upper crustal structure with data from a dense seismic array deployed around Mount St. Helens for 2 weeks in the summer of 2014. Interstation cross correlations of ambient seismic noise data from the array were obtained, and clear fundamental mode Rayleigh waves were observed between 2.5 and 5 s periods. In addition, higher-mode signals were observed around 2 s period. Frequency-time analysis was applied to measure fundamental mode Rayleigh wave phase velocities, which were used to invert for 2-D phase velocity maps. An azimuth-dependent traveltime correction was implemented to mitigate potential biases introduced due to an inhomogeneous noise source distribution. Reliable phase velocity maps were only obtained between 3 and 4 s periods due to limitations imposed by the array aperture and higher-mode contamination. The phase velocity tomography results, which are sensitive to structure shallower than 6 km depth, reveal an ~10–15% low-velocity anomaly centered beneath the volcanic edifice and peripheral high-velocity anomalies that likely correspond to cooled igneous intrusions. We suggest that the low-velocity anomaly reflects the high-porosity mixture of lava and ash deposits near the surface of the edifice, a highly fractured magmatic conduit and hydrothermal system beneath the volcano, and possibly a small contribution from silicate melt.

Evidence for degassing of fresh magma during the 2004-2008 eruption of Mount St. Helens: Subtle signals from the hydrothermal system

Science.gov (United States)

Bergfeld, Deborah; Evans, William C.; Spicer, Kurt R.; Hunt, Andrew G.; Kelly, Peter

2017-01-01

Results from chemical and isotopic analyses of water and gas collected between 2002 and 2016 from sites on and around Mount St. Helens are used to assess magmatic degassing related to the 2004-2008 eruption. During 2005 the chemistry of hot springs in The Breach of Mount St. Helens showed no obvious response to the eruption, and over the next few years, changes were subtle, giving only slight indications of perturbations in the system. By 2010 however, water chemistry, temperatures, and isotope compositions (δD and δ18O) clearly indicated some inputs of volatiles and heat associated with the eruption, but the changes were such that they could be attributed to a pre-existing, gas depleted magma. An increase of ~ 1.5‰ in the δ13C values of dissolved carbon in the springs was noted in 2006 and continued through 2009, a change that was mirrored by a similar shift in δ13C-CO2 in bubble gas emissions. These changes require input of a new source of carbon to the hydrothermal system and provide clear evidence of CO2 from an undegassed body of magma. Rising trends in 3He/4He ratios in gas also accompanied the increases in δ13C. Since 2011 maximum RC/RA values are ≥ 6.4 and are distinctly higher than 5 samples collected between 1986 and 2002, and provide additional evidence for some involvement of new magma as early as 2006, and possibly earlier, given the unknown time needed for CO2 and He to traverse the system and arrive at the springs.

Long-term autonomous volcanic gas monitoring with Multi-GAS at Mount St. Helens, Washington, and Augustine Volcano, Alaska

Science.gov (United States)

Kelly, P. J.; Ketner, D. M.; Kern, C.; Lahusen, R. G.; Lockett, C.; Parker, T.; Paskievitch, J.; Pauk, B.; Rinehart, A.; Werner, C. A.

2015-12-01

In recent years, the USGS Volcano Hazards Program has worked to implement continuous real-time in situ volcanic gas monitoring at volcanoes in the Cascade Range and Alaska. The main goal of this ongoing effort is to better link the compositions of volcanic gases to other real-time monitoring data, such as seismicity and deformation, in order to improve baseline monitoring and early detection of volcanic unrest. Due to the remote and difficult-to-access nature of volcanic-gas monitoring sites in the Cascades and Alaska, we developed Multi-GAS instruments that can operate unattended for long periods of time with minimal direct maintenance from field personnel. Our Multi-GAS stations measure H2O, CO2, SO2, and H2S gas concentrations, are comprised entirely of commercial off-the-shelf components, and are powered by small solar energy systems. One notable feature of our Multi-GAS stations is that they include a unique capability to perform automated CO2, SO2, and H2S sensor verifications using portable gas standards while deployed in the field, thereby allowing for rigorous tracking of sensor performances. In addition, we have developed novel onboard data-processing routines that allow diagnostic and monitoring data - including gas ratios (e.g. CO2/SO2) - to be streamed in real time to internal observatory and public web pages without user input. Here we present over one year of continuous data from a permanent Multi-GAS station installed in August 2014 in the crater of Mount St. Helens, Washington, and several months of data from a station installed near the summit of Augustine Volcano, Alaska in June 2015. Data from the Mount St. Helens Multi-GAS station has been streaming to a public USGS site since early 2015, a first for a permanent Multi-GAS site. Neither station has detected significant changes in gas concentrations or compositions since they were installed, consistent with low levels of seismicity and deformation.

Isotopic composition of carbon in dacitic gases from Usu volcano (Japan). Relationship between the 13C/12C ratio of volatiles and the 87Sr/86Sr ratio of silicates in arc volcanism

International Nuclear Information System (INIS)

Allard, Patrick

1981-01-01

CO 2 emitted at 568 deg C by the new dacitic intrusion in Usu volcano (Japan) has a 13 C/ 12 C ratio of -4.4 per mill vs PDB. Such a value, together with previous isotopic data from other volcanoes in Japan, Indonesia, Central America, Lesser Antilles and New Zealand, enhance that the carbon released by magmas in subduction zones is systematically 13 C-enriched with respect to the primary carbon from rift areas. Such a 13 C enrichment in volatiles is explained in terms of crustal contamination by sedimentary carbon, and can be sowewhat related to a simultaneous increase of 87 Sr in the magma [fr

Constraining the Magmatic System at Mount St. Helens (2004-2008) Using Bayesian Inversion With Physics-Based Models Including Gas Escape and Crystallization

International Nuclear Information System (INIS)

Wong, Ying-Qi; Segall, Paul; Bradley, Andrew; Anderson, Kyle

2017-01-01

Physics-based models of volcanic eruptions track conduit processes as functions of depth and time. When used in inversions, these models permit integration of diverse geological and geophysical data sets to constrain important parameters of magmatic systems. We develop a 1-D steady state conduit model for effusive eruptions including equilibrium crystallization and gas transport through the conduit and compare with the quasi-steady dome growth phase of Mount St. Helens in 2005. Viscosity increase resulting from pressure-dependent crystallization leads to a natural transition from viscous flow to frictional sliding on the conduit margin. Erupted mass flux depends strongly on wall rock and magma permeabilities due to their impact on magma density. Including both lateral and vertical gas transport reveals competing effects that produce nonmonotonic behavior in the mass flux when increasing magma permeability. Using this physics-based model in a Bayesian inversion, we link data sets from Mount St. Helens such as extrusion flux and earthquake depths with petrological data to estimate unknown model parameters, including magma chamber pressure and water content, magma permeability constants, conduit radius, and friction along the conduit walls. Even with this relatively simple model and limited data, we obtain improved constraints on important model parameters. We find that the magma chamber had low (<5 wt %) total volatiles and that the magma permeability scale is well constrained at ~10 –11.4 m 2 to reproduce observed dome rock porosities. Here, compared with previous results, higher magma overpressure and lower wall friction are required to compensate for increased viscous resistance while keeping extrusion rate at the observed value.

Where is the hot rock and where is the ground water – Using CSAMT to map beneath and around Mount St. Helens

Science.gov (United States)

Wynn, Jeff; Mosbrucker, Adam; Pierce, Herbert; Spicer, Kurt R.

2016-01-01

We have observed several new features in recent controlled-source audio-frequency magnetotelluric (CSAMT) soundings on and around Mount St. Helens, Washington State, USA. We have identified the approximate location of a strong electrical conductor at the edges of and beneath the 2004–08 dome. We interpret this conductor to be hot brine at the hot-intrusive-cold-rock interface. This contact can be found within 50 meters of the receiver station on Spine 5, which extruded between April and July of 2005. We have also mapped separate regional and glacier-dome aquifers, which lie one atop the other, out to considerable distances from the volcano.

Conduit degassing and thermal controls on eruption styles at Mount St. Helens

Science.gov (United States)

Schneider, Andrew; Rempel, Alan W.; Cashman, Katharine V.

2012-12-01

The explosivity of silicic eruptions depends on the interplay between magma rheology, exsolution kinetics, and degassing. Magma degassing is governed by the competing effects of vertical transport within the conduit and the lateral flux of gas out of the conduit (Diller et al., 2006; Jaupart and Allegre, 1991). We combine a simplified treatment of these degassing processes with thermodynamic modeling to examine the conditions present at Mount St. Helens during the spine extruding eruption from 2004 to 2008. We find that two parameters are primarily responsible for controlling the eruptive style: the magma chamber temperature, and a dimensionless parameter that gauges the efficiency of lateral degassing. Together, these parameters determine whether and where magma can solidify at depth to form a dense solid plug that is gradually extruded as a volcanic spine. We show that the small (50 oC) decrease in magma chamber temperature between eruptive activity in the 1980s and that of 2004-2008, combined with a modest increase in degassing efficiency associated with lower volumetric flux, can explain the observed change in erupted material from viscous lava flows to solidified spines. More generally, we suggest that similar threshold behavior may explain observed abrupt transitions in effusive eruptive styles at other intermediate composition volcanoes. Finally, we extrapolate our results to suggest that the increase in degassing efficiency accompanying decreasing magma supply rates may have caused the transition from explosive to effusive activity in late 1980.

Education and Outreach through Ludo-Pedagogy and Experiential Learning. Bridging Feminist and Diversity Movements in Today's Nicaragua: An Interview with Helen Alfaro, Yova Briones, and Tannia Rizo Lazo of La Casa de los Colores

Science.gov (United States)

DeGrave, Analisa

2016-01-01

La Casa de los Colores (the House of Colors) is a feminist organization dedicated to defending human rights, particularly those of the LGBTQ+ community in León, Nicaragua. In 2016 Helen Alfaro, Yova Briones, Ani Guerrero, and Tannia Rizo Lazo, four members of La Casa's leadership team, "Las Coloras," were invited to speak about…

Reading, Trauma and Literary Caregiving 1914-1918: Helen Mary Gaskell and the War Library.

Science.gov (United States)

Haslam, Sara

2018-03-28

This article is about the relationship between reading, trauma and responsive literary caregiving in Britain during the First World War. Its analysis of two little-known documents describing the history of the War Library, begun by Helen Mary Gaskell in 1914, exposes a gap in the scholarship of war-time reading; generates a new narrative of "how," "when," and "why" books went to war; and foregrounds gender in its analysis of the historiography. The Library of Congress's T. W. Koch discovered Gaskell's ground-breaking work in 1917 and reported its successes to the American Library Association. The British Times also covered Gaskell's library, yet researchers working on reading during the war have routinely neglected her distinct model and method, skewing the research base on war-time reading and its association with trauma and caregiving. In the article's second half, a literary case study of a popular war novel demonstrates the extent of the "bitter cry for books." The success of Gaskell's intervention is examined alongside H. G. Wells's representation of textual healing. Reading is shown to offer sick, traumatized and recovering combatants emotional and psychological caregiving in ways that she could not always have predicted and that are not visible in the literary/historical record.

The past, present, and future of paediatric cardiology training at the Johns Hopkins Hospital, in the tradition of Dr Helen Taussig.

Science.gov (United States)

Beasley, Gary S; Murphy, Anne M; Brenner, Joel I; Ravekes, William J

2016-12-01

Johns Hopkins has been a leader in paediatric cardiology for over 85 years. In the 1940s, Dr Helen Taussig began training fellows in paediatric cardiology at Johns Hopkins at a time when the diagnosis and treatment of CHD were in the earliest stage. Under her leadership, the fellowship developed a strong foundation that has continued to evolve to meet the current needs of learners and educators. In the current era, the Johns Hopkins programme implements the current theories of adult education and actively engages our fellows in learning as well as teaching. The programme uses techniques such as flipped classroom, structured case-based small-group learning, observed and structured clinical examination, simulations, and innovative educational technology. These strategies combined with our faculty and rich history give our fellows a unique educational experience.

Use of thermal infrared imaging for monitoring renewed dome growth at Mount St. Helens, 2004: Chapter 17 in A volcano rekindled: the renewed eruption of Mount St. Helens, 2004-2006

Science.gov (United States)

Schneider, David J.; Vallance, James W.; Wessels, Rick L.; Logan, Matthew; Ramsey, Michael S.; Sherrod, David R.; Scott, William E.; Stauffer, Peter H.

2008-01-01

A helicopter-mounted thermal imaging radiometer documented the explosive vent-clearing and effusive phases of the eruption of Mount St. Helens in 2004. A gyrostabilized gimbal controlled by a crew member housed the radiometer and an optical video camera attached to the nose of the helicopter. Since October 1, 2004, the system has provided thermal and video observations of dome growth. Flights conducted as frequently as twice daily during the initial month of the eruption monitored rapid changes in the crater and 1980-86 lava dome. Thermal monitoring decreased to several times per week once dome extrusion began. The thermal imaging system provided unique observations, including timely recognition that the early explosive phase was phreatic, location of structures controlling thermal emissions and active faults, detection of increased heat flow prior to the extrusion of lava, and recognition of new lava extrusion. The first spines, 1 and 2, were hotter when they emerged (maximum temperature 700-730°C) than subsequent spines insulated by as much as several meters of fault gouge. Temperature of gouge-covered spines was about 200°C where they emerged from the vent, and it decreased rapidly with distance from the vent. The hottest parts of these spines were as high as 500-730°C in fractured and broken-up regions. Such temperature variation needs to be accounted for in the retrieval of eruption parameters using satellite-based techniques, as such features are smaller than pixels in satellite images.

Managing public and media response to a reawakening volcano: lessons from the 2004 eruptive activity of Mount St. Helens: Chapter 23 in A volcano rekindled: the renewed eruption of Mount St. Helens, 2004-2006

Science.gov (United States)

Frenzen, Peter M.; Matarrese, Michael T.; Sherrod, David R.; Scott, William E.; Stauffer, Peter H.

2008-01-01

Volcanic eruptions and other infrequent, large-scale natural disturbances pose challenges and opportunities for public-land managers. In the days and weeks preceding an eruption, there can be considerable uncertainty surrounding the magnitude and areal extent of eruptive effects. At the same time, public and media interest in viewing developing events is high and concern for public safety on the part of local land managers and public safety officials is elevated. Land managers and collaborating Federal, State, and local officials must decide whether evacuations or restrictions to public access are necessary, the appropriate level of advance preparation, and how best to coordinate between overlapping jurisdictions. In the absence of a formal Federal or State emergency declaration, there is generally no identified source of supplemental funding for emergency-response preparation or managing extraordinary public and media response to developing events. In this chapter, we examine responses to escalating events that preceded the 2004 Mount St. Helens eruption and changes in public perception during the extended period of the largely nonexplosive, dome-building eruption that followed. Lessons learned include the importance of maintaining up-to-date emergency-response plans, cultivating close working relationships with collaborating agencies, and utilizing an organized response framework that incorporates clearly defined roles and responsibilities and effective communication strategies.

Magma Chamber Model of Batur Caldera, Bali, Indonesia: Compositional Variation of Two Facies, Large-Volume Dacitic Ignimbrites

Directory of Open Access Journals (Sweden)

Igan S. Sutawidjaja

2015-05-01

Full Text Available DOI:10.17014/ijog.2.2.111-124Batur is one of the finest known calderas on Earth, and is the source of at least two major ignimbrite eruptions with a combined volume of some 84 km3 and 19 km3. These ignimbrites have a similar compositions, raising the question of whether they are geneticaly related. The Batur Ignimbrite-1 (BI-1 is crystal poor, containing rhyodacitic (68 - 70wt % SiO2, white to grey pumices and partly welded and unwelded. The overlying Batur Ignimbrite-2 (BI-2 is a homogeneous grey to black dacitic pumices (64 - 66 wt % SiO2, unwelded and densely welded (40 - 60% vesicularity, crystal and lithic rich. Phase equilibria indicate that the Batur magma equilibrated at temperatures of 1100 - 1300oC with melt water contents of 3 - 6 wt%. The post-eruptive Batur magma was cooler (<1100oC and it is melt more water rich (> 6 wt % H2O. A pressure of 20 kbar is infered from mineral barometry for the Batur magma chamber. Magmatic chamber model is one in which crystals and melt separate from a convecting Batur magma by density differences, resulting in a stratified magma chamber with a homogeneous central zone, a crystal-rich accumulation zone near the walls or base, and a buoyant, melt-rich zone near the top. This is consistent with the estimated magma temperatures and densities: the pre-eruptive BI-1 magma was hoter (1300oC and more volatile rich (6 wt % H2O with density 2.25 g/cm3 than the BI-2 magma (1200oC; 4 wt % H2O in density was higher (2.50 g/cm3. Batur melt characteristics and intensive parameters are consistent with a volatile oversaturation-driven eruption. However, the higher H2O content, high viscosity and low crystal content of the BI-1 magma imply an external eruption trigger.

Pseudotachylyte formation in volcanic conduits: Montserrat vs. Mount St. Helens

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Kendrick, J. E.; Lavallee, Y.; Petrakova, L.; Ferk, A.; Di Toro, G.; Hess, K.; Ferri, F.; Dingwell, D. B.

2012-12-01

Seismogenic fracture and faulting may result in non-equilibrium frictional melting of rock, which upon cooling and recrystallisation forms pseudotachylyte. In volcanic environments, the transition from endogenous to exogenous growth can be attributed to a shift in magma rheology into the brittle regime, and thus the ascent of high-viscosity magma can form discrete shear zones, comparable to tectonic faults, along conduit margins. Pseudotachylytes have, until now, rarely been noted in exogenous volcanic materials and seldom in active volcanic environments. This is despite the simultaneous occurrence of high pressures and differential stresses, which make high-viscosity magmas ideal candidates for the occurrence of frictional melting. Here, we compare the chemical, thermal, magnetic and structural properties of two candidate volcanic pseudotachylytes; one from Soufriere Hills (Montserrat) and one from Mount St. Helens (USA). Additionally, we present data from a set of high-velocity rotary shear experiments on the host materials of these natural pseudotachylytes in which melting was induced after just 10's of centimeters of slip at realistic extrusion velocities (0.4 - 1.6 ms-1) and low normal stresses (0.5-2 MPa). After 1-2 meters of slip a continuous melt layer formed, at which point friction decreased and the fault zone displayed slip-weakening behaviour. For volcanic conduits, this would facilitate temporarily elevated slip rates, or an increase in extrusion rate, and could cause transitions in dome morphology and eruption style. This study demonstrates that shear fracturing in magma or sliding along conduit margins can readily result in frictional melting. The conspicuous absence of pseudotachylytes in active volcanic environments is likely the result of exceptionally high background temperatures which precipitate near-equilibrium melting, thereby obviating one of the characteristic signatures of pseudotachylyte - glassy protomelts formed by selective melting of

Large-scale magnetic field perturbation arising from the 18 May 1980 eruption from Mount St. Helens, Washington

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Mueller, R.J.; Johnston, M.J.S.

1989-01-01

A traveling magnetic field disturbance generated by the 18 may 1980 eruption of Mount St. Helens at 1532 UT was detected on an 800-km linear array of recording magnetometers installed along the San Andreas fault system in California, from San Francisco to the Salton Sea. Arrival times of the disturbance field, from the most northern of these 24 magnetometers (996 km south of the volcano) to the most southern (1493 km S23?? E), are consistent with the generation of a traveling ionospheric disturbance stimulated by the blast pressure wave in the atmosphere. The first arrivals at the north and the south ends of the array occurred at 26 and 48 min, respectively, after the initial eruption. Apparent average wave velocity through the array is 309 ?? 14 m s-1 but may have approached 600 m s-1 close to the volcano. The horizontal phase and the group velocity of ??? 300 m s-1 at periods of 70-80 min, and the attenuation with distance, strongly suggest that the magnetic field perturbations at distances of 1000-1500 km are caused by gravity mode acoustic-gravity waves propagating at F-region heights in the ionosphere. ?? 1989.

Four-year prospective study of the respiratory effects of volcanic ash from Mt. St. Helens

International Nuclear Information System (INIS)

Buist, A.S.; Vollmer, W.M.; Johnson, L.R.; Bernstein, R.S.; McCamant, L.E.

1986-01-01

This report describes the 4-yr follow-up of 712 loggers exposed over an extended period to varying levels of fresh volcanic ash from the 1980 eruptions of Mt. St. Helens. Concerns related to the irritant effect the ash might have on the airways and also to its fibrogenic potential if exposures were intense and continued over many years. Our subjects were divided into 3 groups: high, low, and no exposure. Baseline testing was begun in June 1980, 1 month after the major eruption, and follow-up testing continued on an annual basis through 1984; 88% of the loggers have been tested at least 3 times. Analysis of lung function data showed that a significant, exposure-related decline in FEV1 occurred during the first year after the eruption. The decline was short-lived, however, and by 1984 the differences between exposure groups were no longer significant. Self-reported symptoms of cough, phlegm, and wheeze showed a similar pattern. No ash-related changes were seen in chest roentgenograms taken in 1980 and in 1984. Our findings are consistent with the hypothesis that the inhaled ash caused mucus hypersecretion and/or airway inflammation that reversed when the exposure levels decreased. The ash levels to which the loggers were exposed were low compared with permissible occupational levels for nuisance dusts, but generally higher than the total suspended particulate levels permissible in ambient air

Correlations of turbidity to suspended-sediment concentration in the Toutle River Basin, near Mount St. Helens, Washington, 2010-11

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Uhrich, Mark A.; Kolasinac, Jasna; Booth, Pamela L.; Fountain, Robert L.; Spicer, Kurt R.; Mosbrucker, Adam R.

2014-01-01

Researchers at the U.S. Geological Survey, Cascades Volcano Observatory, investigated alternative methods for the traditional sample-based sediment record procedure in determining suspended-sediment concentration (SSC) and discharge. One such sediment-surrogate technique was developed using turbidity and discharge to estimate SSC for two gaging stations in the Toutle River Basin near Mount St. Helens, Washington. To provide context for the study, methods for collecting sediment data and monitoring turbidity are discussed. Statistical methods used include the development of ordinary least squares regression models for each gaging station. Issues of time-related autocorrelation also are evaluated. Addition of lagged explanatory variables was used to account for autocorrelation in the turbidity, discharge, and SSC data. Final regression model equations and plots are presented for the two gaging stations. The regression models support near-real-time estimates of SSC and improved suspended-sediment discharge records by incorporating continuous instream turbidity. Future use of such models may potentially lower the costs of sediment monitoring by reducing time it takes to collect and process samples and to derive a sediment-discharge record.

The effect of consumers and mutualists of Vaccinium membranaceum at Mount St. Helens: dependence on successional context.

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Suann Yang

Full Text Available In contrast to secondary succession, studies of terrestrial primary succession largely ignore the role of biotic interactions, other than plant facilitation and competition, despite the expectation that simplified interaction webs and propagule-dependent demographics may amplify the effects of consumers and mutualists. We investigated whether successional context determined the impact of consumers and mutualists by quantifying their effects on reproduction by the shrub Vaccinium membranaceum in primary and secondary successional sites at Mount St. Helens (Washington, USA, and used simulations to explore the effects of these interactions on colonization. Species interactions differed substantially between sites, and the combined effect of consumers and mutualists was much more strongly negative for primary successional plants. Because greater local control of propagule pressure is expected to increase successional rates, we evaluated the role of dispersal in the context of these interactions. Our simulations showed that even a small local seed source greatly increases population growth rates, thereby balancing strong consumer pressure. The prevalence of strong negative interactions in the primary successional site is a reminder that successional communities will not exhibit the distribution of interaction strengths characteristic of stable communities, and suggests the potential utility of modeling succession as the consequence of interaction strengths.

Rapid, low-cost photogrammetry to monitor volcanic eruptions: an example from Mount St. Helens, Washington, USA

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Diefenbach, Angela K.; Crider, Juliet G.; Schilling, Steve P.; Dzurisin, Daniel

2012-01-01

We describe a low-cost application of digital photogrammetry using commercially available photogrammetric software and oblique photographs taken with an off-the-shelf digital camera to create sequential digital elevation models (DEMs) of a lava dome that grew during the 2004–2008 eruption of Mount St. Helens (MSH) volcano. Renewed activity at MSH provided an opportunity to devise and test this method, because it could be validated against other observations of this well-monitored volcano. The datasets consist of oblique aerial photographs (snapshots) taken from a helicopter using a digital single-lens reflex camera. Twelve sets of overlapping digital images of the dome taken during 2004–2007 were used to produce DEMs and to calculate lava dome volumes and extrusion rates. Analyses of the digital images were carried out using photogrammetric software to produce three-dimensional coordinates of points identified in multiple photos. The evolving morphology of the dome was modeled by comparing successive DEMs. Results were validated by comparison to volume measurements derived from traditional vertical photogrammetric surveys by the US Geological Survey Cascades Volcano Observatory. Our technique was significantly less expensive and required less time than traditional vertical photogrammetric techniques; yet, it consistently yielded volume estimates within 5% of the traditional method. This technique provides an inexpensive, rapid assessment tool for tracking lava dome growth or other topographic changes at restless volcanoes.

Two Millian Arguments: Using Helen Longino’s Approach to Solve the Problems Philip Kitcher Targeted with His Argument on Freedom of Inquiry

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Jaana Eigi

2012-12-01

Full Text Available Philip Kitcher argued that the freedom to pursue one's version of the good life is the main aim of Mill's argument for freedom of expression. According to Kitcher, in certain scientific fields, political and epistemological asymmetries bias research toward conclusions that threaten this most important freedom of underprivileged groups. Accordingly, Kitcher claimed that there are Millian grounds for limiting freedom of inquiry in these fields to protect the freedom of the underprivileged.I explore Kitcher's argument in light of the interpretation Helen Longino gave to Mill's argument. She argued that free critical dialogue in the community allows bias to be overcome, through intersubjective criticism of hypotheses and the background assumptions that frame them.I suggest that Longino's approach allows for the identification of the fundamental problems of the research programs Kitcher targeted, and for the rejection of their claims to knowledge. Thus it is possible to address Kitcher's problem without limiting freedom of speech.

Investigation of Mineral Alteration in Andesite and Dacite from Three Different Volcano Hydrothermal Systems on Dominica, Lesser Antilles

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Smith, C. I. V.; Frey, H. M.; Joseph, E. P.; Manon, M. R. F.

2017-12-01

The thermal discharges of Dominica are classified as steam-heated acidic-sulphate waters, produced by the mixing of shallow ground waters heated by sulphur bearing gases coming from magmatic sources. This study investigates the mineral alteration associated with three hydrothermal areas in Dominica that exhibit different temperature, pH, water composition and surface water abundance. Hydrothermal features (fumaroles, pools, springs) from Sulphur Springs ranged in temperature from 41 - 97 °C and pH from 1-3 in a predominantly gaseous environment, whereas the Valley of Desolation (69-98 °C and pH 1- 4) and the Cold Soufriere (18-32 °C and pH 1-4) have significant inputs of surface water. At each location, the host andesite-dacite rock was enveloped by a thin rind (up 2 cm) of precipitates, but the degree of alteration and rind thickness/composition varied with location. Cobbles from Sulphur Springs (SS) are grayish white in color with a thin outer rind (3-13 mm), and seemingly unaltered cores. Valley of Desolation (VoD) samples have a variety of patterns of alteration, with some clasts a uniform white-orange color, whereas others have variable thicknesses of an altered rind (1-20 mm), with relatively unaltered cores. Multiple hydrothermal minerals precipitated in the outer rinds display distinctive colors, suggestive of sulphides (dark gray), sulphates (orange and yellow), and iron oxides(?) (pink and purple). Cold Soufriere (CS) samples appear to be the most altered, often crumbling at touch. Others had rinds (2-10 mm) and pinkish gray cores that suggest more alteration compared to VoD and SS samples. Preliminary mineral identification of rind compositions was determined by XRD. Scans indicate the presence of silica polymorphs cristobalite and tridymite, as well as pyrite and sulphur. Elemental maps created using a SEM to identify any gradation caused by the elemental leaching and/or precipitation show that the boundaries between the weathering rind and the host

Airborne thermal infrared imaging of the 2004-2005 eruption of Mount St. Helens

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Schneider, D. J.; Vallance, J. W.; Logan, M.; Wessels, R.; Ramsey, M.

2005-12-01

A helicopter-mounted forward-looking infrared imaging radiometer (FLIR) documented the explosive and effusive activity at Mount St. Helens during the 2004-2005 eruption. A gyrostabilzed gimbal controlled by a crew member houses the FLIR radiometer and an optical video camera attached at the lower front of the helicopter. Since October 1, 2004 the system has provided an unprecedented data set of thermal and video dome-growth observations. Flights were conducted as frequently as twice daily during the initial month of the eruption (when changes in the crater and dome occurred rapidly), and have been continued on a tri-weekly basis during the period of sustained dome growth. As with any new technology, the routine use of FLIR images to aid in volcano monitoring has been a learning experience in terms of observation strategy and data interpretation. Some of the unique information that has been derived from these data to date include: 1) Rapid identification of the phreatic nature of the early explosive phase; 2) Observation of faulting and associated heat flow during times of large scale deformation; 3) Venting of hot gas through a short lived crater lake, indicative of a shallow magma source; 4) Increased heat flow of the crater floor prior to the initial dome extrusion; 5) Confirmation of new magma reaching the surface; 6) Identification of the source of active lava extrusion, dome collapse, and block and ash flows. Temperatures vary from ambient, in areas insulated by fault gouge and talus produced during extrusion, to as high as 500-740 degrees C in regions of active extrusion, collapse, and fracturing. This temperature variation needs to be accounted for in the retrieval of eruption parameters using satellite-based techniques as such features are sub-pixel size in satellite images.

The 2004–2008 dome-building eruption at Mount St. Helens, Washington: Epilogue

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Dzurisin, Daniel; Moran, Seth C.; Lisowski, Michael; Schilling, Steve P.; Anderson, Kyle R.; Werner, Cynthia A.

2015-01-01

The 2004–2008 dome-building eruption at Mount St. Helens ended during winter 2007–2008 at a time when field observations were hampered by persistent bad weather. As a result, recognizing the end of the eruption was challenging—but important for scientists trying to understand how and why long-lived eruptions end and for public officials and land managers responsible for hazards mitigation and access restrictions. In hindsight, the end of the eruption was presaged by a slight increase in seismicity in December 2007 that culminated on January 12–13, 2008, with a burst of more than 500 events, most of which occurred in association with several tremor-like signals and a spasmodic burst of long-period earthquakes. At about the same time, a series of regular, localized, small-amplitude tilt events—thousands of which had been recorded during earlier phases of the eruption—came to an end. Thereafter, seismicity declined to 10–20 events per day until January 27–28, when a spasmodic burst of about 50 volcano-tectonic earthquakes occurred over a span of 3 h. This was followed by a brief return of repetitive “drumbeat” earthquakes that characterized much of the eruption. By January 31, however, seismicity had declined to 1–2 earthquakes per day, a rate similar to pre-eruption levels. We attribute the tilt and seismic observations to convulsive stagnation of a semisolid magma plug in the upper part of the conduit. The upward movement of the plug ceased when the excess driving pressure, which had gradually decreased throughout the eruption as a result of reservoir deflation and increasing overburden from the growing dome, was overcome by increasing friction as a result of cooling and crystallization of the plug.

Magma storage constrains by compositional zoning of plagioclase from dacites of the caldera forming eruptions of Vetrovoy Isthmus and Lvinaya Past’ Bay (Iturup Island, Kurile Islands)

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Maksimovich, I. A.; Smirnov, S. Z.; Kotov, A. A.; Timina, T. Yu; Shevko, A. V.

2017-12-01

The Vetrovoy Isthmus and the Lvinaya Past’ Bay on the Iturup island (Kuril island arc) are the results of large Plinian eruptions of compositionally similar dacitic magmas. This study is devoted to a comparative analysis of the storage and crystallization conditions for magma reservoirs, which were a source of large-scale explosive eruptions. The plagioclase is most informative mineral in studying of the melt evolution. The studied plagioclases possess a complex zoning patterns, which are not typical for silicic rocks in island-arc systems. It was shown that increase of Ca in the plagioclase up to unusually high An95 is related to increase of H2O pressure in both volcanic magma chambers. The study revealed that minerals of the Vetrovoy Isthmus and Lvinaya Past’ crystallized from compositionally similar melts. Despite the compositional similarity of the melts, the phenocryst assemblage of the Lvinaya Past’ differs from the Vetrovoy Isthmus by the presence of the amphibole, which indicates that the pressure in the magmatic chamber exceeded 1-2 kbar at a 4-6 wt. % of H2O in the melt. The rocks of the Vetrovoy Isthmus do not contain amphibole phenocrysts, but melt and fluid inclusions assemblages in plagioclase demonstrate that the magma degassed in the course of evolution. This is an indication that the pressure did not exceed significantly 1-2 kbar.

Clast comminution during pyroclastic density current transport: Mt St Helens

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Dawson, B.; Brand, B. D.; Dufek, J.

2011-12-01

Volcanic clasts within pyroclastic density currents (PDCs) tend to be more rounded than those in fall deposits. This rounding reflects degrees of comminution during transport, which produces an increase in fine-grained ash with distance from source (Manga, M., Patel, A., Dufek., J. 2011. Bull Volcanol 73: 321-333). The amount of ash produced due to comminution can potentially affect runout distance, deposit sorting, the volume of ash lofted into the upper atmosphere, and increase internal pore pressure (e.g., Wohletz, K., Sheridan, M. F., Brown, W.K. 1989. J Geophy Res, 94, 15703-15721). For example, increased pore pressure has been shown to produce longer runout distances than non-comminuted PDC flows (e.g., Dufek, J., and M. Manga, 2008. J. Geophy Res, 113). We build on the work of Manga et al., (2011) by completing a pumice abrasion study for two well-exposed flow units from the May 18th, 1980 eruption of Mt St Helens (MSH). To quantify differences in comminution from source, sampling and the image analysis technique developed in Manga et al., 2010 was completed at distances proximal, medial, and distal from source. Within the units observed, data was taken from the base, middle, and pumice lobes within the outcrops. Our study is unique in that in addition to quantifying the degree of pumice rounding with distance from source, we also determine the possible range of ash sizes produced during comminution by analyzing bubble wall thickness of the pumice through petrographic and SEM analysis. The proportion of this ash size is then measured relative to the grain size of larger ash with distance from source. This allows us to correlate ash production with degree of rounding with distance from source, and determine the fraction of the fine ash produced due to comminution versus vent-fragmentation mechanisms. In addition we test the error in 2D analysis by completing a 3D image analysis of selected pumice samples using a Camsizer. We find that the roundness of PDC

Revolution and Exploration: the English Translations of Rousseau and Humboldt by Helen Maria Williams

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Paula Yurss Lasanta

2017-12-01

Full Text Available British author Helen Maria Williams (1759-1827 was a well-known figure in the eighteenth century literary circles, whose work was praised by Elizabeth Montagu, Samuel Johnson, Dorothy and William Wordsworth, Mary Wollstonecraft, Hester Piozzi or Alexander von Humboldt.  In her early poems  Edwin and Eltruda (1782, An Ode to the Peace (1783 and Peru (1784, Williams starts to reveal her political tendencies by appealing to strong empathic feelings as a key to social and political transformation. As a result of her interest in politics, she travelled to France in 1790 and published her most acclaimed work Letters from France (1790. However, the rest of her production has received little critical attention by modern scholars, who have overlooked her involvement in translation. Williams’ only extant novel, Julia (1790 is in fact a creative translation of Rousseau’s Julie ou La Nouvelle Héloïse (1761, in which Williams includes poems that evidence her interest in revolutionary politics. Four years later, she translated Bernardin de Saint Pierre’s Paul et Virginie, while she was imprisoned in Paris. While translating novels was regarded as a respectable exercise for women writers, Williams challenges gender assumptions by translating Researches (1814 and the seven volumes of Personal Narrative (1814-1829, which had been produced by one of the most influential eighteenth century scientists, Alexander von Humboldt. This article interrogates how Williams makes use of translation to access areas of knowledge traditionally restricted to men, such as philosophy, politics and science. For this purpose, I will focus on her translations of the work of two leading intellectual figures of the eighteenth century,  Rousseau and Von Humboldt.

A New Perspective on Mount St. Helens - Dramatic Landform Change and Associated Hazards at the Most Active Volcano in the Cascade Range

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Ramsey, David W.; Driedger, Carolyn L.; Schilling, Steve P.

2008-01-01

Mount St. Helens has erupted more frequently than any other volcano in the Cascade Range during the past 4,000 years. The volcano has exhibited a variety of eruption styles?explosive eruptions of pumice and ash, slow but continuous extrusions of viscous lava, and eruptions of fluid lava. Evidence of the volcano?s older eruptions is recorded in the rocks that build and the deposits that flank the mountain. Eruptions at Mount St. Helens over the past three decades serve as reminders of the powerful geologic forces that are reshaping the landscape of the Pacific Northwest. On May 18, 1980, a massive landslide and catastrophic explosive eruption tore away 2.7 cubic kilometers of the mountain and opened a gaping, north-facing crater. Lahars flowed more than 120 kilometers downstream, destroying bridges, roads, and buildings. Ash from the eruption fell as far away as western South Dakota. Reconstruction of the volcano began almost immediately. Between 1980 and 1986, 80 million cubic meters of viscous lava extruded episodically onto the crater floor, sometimes accompanied by minor explosions and small lahars. A lava dome grew to a height of 267 meters, taller than the highest buildings in the nearby city of Portland, Oregon. Crater Glacier formed in the deeply shaded niche between the 1980-86 lava dome and the south crater wall. Its tongues of ice flowed around the east and west sides of the dome. Between 1989 and 1991, multiple explosions of steam and ash rocked the volcano, possibly a result of infiltrating rainfall being heated in the still-hot interior of the dome and underlying crater floor. In September 2004, rising magma caused earthquake swarms and deformation of the crater floor and glacier, which indicated that Mount St. Helens might erupt again soon. On October 1, 2004, a steam and ash explosion signaled the beginning of a new phase of eruptive activity at the volcano. On October 11, hot rock reached the surface and began building a new lava dome immediately

Diffusive exchange of trace elements between basaltic-andesite and dacitic melt: Insights into potential metal fractionation during magma mixing

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Fiege, A.; Ruprecht, P.; Simon, A. C.; Holtz, F.

2017-12-01

Mafic magma recharge is a common process that triggers physical and chemical mixing in magmatic systems and drives their evolution, resulting in, e.g., hybridization and volcanic eruptions. Once magma-magma contact is initiated, rapid heat-flux commonly leads to the formation of a cooling-induced crystal mush on the mafic side of the interface. Here, on a local scale (µm to cm), at the magma-magma interface, melt-melt diffusive exchange is required to approach equilibrium. Significant chemical potential gradients drive a complex, multi-element mass flux between the two systems (Liang, 2010). This diffusive-equilibration often controls crystal dissolution rates within the boundary layers and, thus, the formation of interconnected melt or fluid networks. Such networks provide important pathways for the transport of volatiles and trace metals from the mafic recharge magma to the felsic host magma, where the latter may feed volcanic activities and ore deposits. While major element diffusion in silicate melts is mostly well understood, even in complex systems, the available data for many trace element metals are limited (Liang, 2010; Zhang et al., 2010). Differences in diffusivity in a dynamic, mixing environment can cause trace element fractionation, in particular during crystallization and volatile exsolution and separation. This may affect trace element signatures in phenocrysts and magmatic volatile phases that can form near a magma-magma boundary. As a result, the chemistry of volcanic gases and magmatic-hydrothermal ore deposits may be partially controlled by such mixing phenomena. We performed melt-melt diffusion-couple experiments at 150 MPa, 1100°C, FMQ, FMQ+1 and FMQ+3 (FMQ: fayalite-magnetite-quartz oxygen fugacity buffer). Hydrated, sulfur-bearing cylinders of dacite and basaltic andesite were equilibrated for up to 20 h. Major and trace element gradients were measured by using laser-ablation ICP-MS and electron microprobe analyses. The results we will

Magma Expansion and Fragmentation in a Propagating Dike (Invited)

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Jaupart, C. P.; Taisne, B.

2010-12-01

edifice. Such behavior can be accounted for by magma fragmentation at the top of a dike. Samples from the Mount St Helens cryptodome had vesiculated and lost some of their gas, and many of them were laced with tuffisite veins. Magma fragmentation within a dike allows efficient degassing due to the combination of three factors. One is that the gas phase is continuous, so that there is no difficulty in separating gas and melt. Furthermore, large internal overpressures are generated, which favors gas expulsion into country rock. A third factor is that dyke ascent is slow, which favours gas loss from the moving magmatic mixture.

The source of infrasound associated with long-period events at mount St. Helens

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Matoza, R.S.; Garces, M.A.; Chouet, B.A.; D'Auria, L.; Hedlin, M.A.H.; De Groot-Hedlin, C.; Waite, G.P.

2009-01-01

During the early stages of the 2004-2008 Mount St. Helens eruption, the source process that produced a sustained sequence of repetitive long-period (LP) seismic events also produced impulsive broadband infrasonic signals in the atmosphere. To assess whether the signals could be generated simply by seismic-acoustic coupling from the shallow LP events, we perform finite difference simulation of the seismo-acoustic wavefield using a single numerical scheme for the elastic ground and atmosphere. The effects of topography, velocity structure, wind, and source configuration are considered. The simulations show that a shallow source buried in a homogeneous elastic solid produces a complex wave train in the atmosphere consisting of P/SV and Rayleigh wave energy converted locally along the propagation path, and acoustic energy originating from , the source epicenter. Although the horizontal acoustic velocity of the latter is consistent with our data, the modeled amplitude ratios of pressure to vertical seismic velocity are too low in comparison with observations, and the characteristic differences in seismic and acoustic waveforms and spectra cannot be reproduced from a common point source. The observations therefore require a more complex source process in which the infrasonic signals are a record of only the broadband pressure excitation mechanism of the seismic LP events. The observations and numerical results can be explained by a model involving the repeated rapid pressure loss from a hydrothermal crack by venting into a shallow layer of loosely consolidated, highly permeable material. Heating by magmatic activity causes pressure to rise, periodically reaching the pressure threshold for rupture of the "valve" sealing the crack. Sudden opening of the valve generates the broadband infrasonic signal and simultaneously triggers the collapse of the crack, initiating resonance of the remaining fluid. Subtle waveform and amplitude variability of the infrasonic signals as

Frictional melting and stick-slip behavior in volcanic conduits

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Kendrick, Jackie Evan; Lavallee, Yan; Hirose, Takehiro; di Toro, Giulio; Hornby, Adrian Jakob; Hess, Kai-Uwe; Dingwell, Donald Bruce

2013-04-01

Dome-building eruptions have catastrophic potential, with dome collapse leading to devastating pyroclastic flows with almost no precursory warning. During dome growth, the driving forces of the buoyant magma may be superseded by controls along conduit margins; where brittle fracture and sliding can lead to formation of lubricating cataclasite and gouge. Under extreme friction, pseudotachylyte may form at the conduit margin. Understanding the conduit margin processes is vital to understanding the continuation of an eruption and we postulate that pseudotachylyte generation could be the underlying cause of stick-slip motion and associated seismic "drumbeats", which are so commonly observed at dome-building volcanoes. This view is supported by field evidence in the form of pseudotachylytes identified in lava dome products at Soufrière Hills (Montserrat) and Mount St. Helens (USA). Both eruptions were characterised by repetitive, periodic seismicity and lava spine extrusion of highly viscous magma. High velocity rotary shear (HVR) experiments demonstrate the propensity for melting of the andesitic and dacitic material (from Soufrière Hills and Mount St. Helens respectively) at upper conduit stress conditions (HVR experiments which mimic rapid velocity fluctuations in stick-slip behavior demonstrate velocity-weakening behavior of melt, with a tendency for unstable slip. During ascent, magma may slip and undergo melting along the conduit margin. In the process the shear resistance of the slip zone is increased, acting as a viscous brake halting slip (the "stick" of stick-slip motion). Sufficient buoyancy-driven pressures from ascending magma below eventually overcome resistance to produce a rapid slip event (the "slip") along the melt-bearing slip zone, which is temporarily lubricated due to velocity-weakening. New magma below experiences the same slip event more slowly (as the magma decompresses) to produce a viscous brake and the process is repeated. This allows a

Bayesian inversion of data from effusive volcanic eruptions using physics-based models: Application to Mount St. Helens 2004--2008

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Anderson, Kyle; Segall, Paul

2013-01-01

Physics-based models of volcanic eruptions can directly link magmatic processes with diverse, time-varying geophysical observations, and when used in an inverse procedure make it possible to bring all available information to bear on estimating properties of the volcanic system. We develop a technique for inverting geodetic, extrusive flux, and other types of data using a physics-based model of an effusive silicic volcanic eruption to estimate the geometry, pressure, depth, and volatile content of a magma chamber, and properties of the conduit linking the chamber to the surface. A Bayesian inverse formulation makes it possible to easily incorporate independent information into the inversion, such as petrologic estimates of melt water content, and yields probabilistic estimates for model parameters and other properties of the volcano. Probability distributions are sampled using a Markov-Chain Monte Carlo algorithm. We apply the technique using GPS and extrusion data from the 2004–2008 eruption of Mount St. Helens. In contrast to more traditional inversions such as those involving geodetic data alone in combination with kinematic forward models, this technique is able to provide constraint on properties of the magma, including its volatile content, and on the absolute volume and pressure of the magma chamber. Results suggest a large chamber of >40 km3 with a centroid depth of 11–18 km and a dissolved water content at the top of the chamber of 2.6–4.9 wt%.

Methane production and oxidation in lakes impacted by the May 18, 1980 eruption of Mount St. Helens

International Nuclear Information System (INIS)

Lilley, M.D.; Baross, J.A.; Dahm, C.N.

1988-01-01

The concentrations of CH 4 and CH 4 oxidation rates were measured in lakes impacted by the May 18, 1980 eruption of Mount St. Helens. The highest CH 4 concentrations were recorded during the first summer after the eruption and ranged in surface waters from 5 microM in the moderately impacted Ryan Lake to 28 microM in the heavily impacted North Coldwater Lake. At depths below the oxic/anoxic interface, CH 4 levels reached 250 microM in North Coldwater Lake, 184 microM in Spirit Lake, 70 microM in Castle Creek lake, and 60 microM in Ryan Lake. The CH 4 flux measurements from these lakes during the summer following the May 18, 1980 eruption were the highest ever recorded in lakes with ranges of 1.1-2.9 mmol CH 4 /sq m/day in the light to moderately impacted McBride and Ryan Lakes to ranges of 17.4-25.3 mmol CH 4 /sq m/day in the heavily impacted Castle Creek, North Coldwater, and Spirit Lakes. Evidence of CH 4 oxidation was seen in all of the lakes during the summer of 1981, and rates of CH 4 oxidation using C 14 -CH 4 were measured in spirit Lake from 1982 to 1986. The highest rates of CH 4 oxidation measured were during the summer stratification and ranged from 50 to 150 nmol CH 4 oxidized/L/day. methane oxidation rates were measured in waters having oxygen concentrations less than 100 microM with highest activity occurring at concentrations of 30-60 microM. 36 refs., 12 figs. 3 tabs

Long term storage of explosively erupted magma at Nevado de Toluca volcano, Mexico

Science.gov (United States)

Arce, J. L.; Gardner, J.; Macias, J. L.

2007-12-01

Dacitic magmas production is common in subduction-related volcanoes, occurring in those with a long period of activity as a result of the magmatic evolution. However, in this evolution many factors (i.e. crystal fractionation, assimilation, magma mixing) can interact to produce dacites. Nevado de Toluca volcano (4,680 masl; 19°09'N; 99°45'W) Central Mexico has recorded a long period of time producing dacites explosively, at least during 42 ka of activity, involving several km3 of magma, with two important Plinian-type eruptions occurred at ~21.7 ka (Lower Toluca Pumice) and ~10.5 ka (Upper Toluca Pumice). Questions like, what was the mechanism responsible to produce voluminous dacitic magma and how the volatiles and pressure changed in the Nevado de Toluca system, remain without answers. Dacites from the Lower Toluca Pumice (LTP) contain plagioclase, amphibole, iron-titanium oxides, and minor resorbed biotite, set in a glassy-vesicular matrix and the Upper Toluca Pumice (UTP) dacites contain the same mineral phases plus orthopyroxene. Ilmenite- ulvospinel geothermometry yielded a temperature of ~860°C for the LTP dacite, a little hotter than the UTP (~ 840°C). Based on hydrothermal experiments data, amphibole is stable above 100 MPa under 900°C, while plagioclase crystallizes up to 250-100 MPa at temperatures of 850-900°C. Pyroxene occurs only at pressures of 200-100 MPa with its respective temperatures of 825-900°C. Water contents in the LTP magma (2-3.5 wt %) are similar to that calculated for the UTP magma (1.3-3.6 wt %). So, there are only small changes in temperature and pressure from ~21.7 ka to 10.5 ka. It is noteworthy that orthopyroxene is absent in the LTP, however reaction-rimmed biotite (probably xenocrystic) is commonly observed in all dacites. Hence, almost all dacitic magmas seem to be stored at relatively similar pressures, water contents, and temperatures. All of these data could suggest repetitive basic magma injections producing the

Self-similar rupture implied by scaling properties of volcanic earthquakes occurring during the 2004-2008 eruption of Mount St. Helens, Washington

Science.gov (United States)

Harrington, Rebecca M.; Kwiatek, Grzegorz; Moran, Seth C.

2015-01-01

We analyze a group of 6073 low-frequency earthquakes recorded during a week-long temporary deployment of broadband seismometers at distances of less than 3 km from the crater at Mount St. Helens in September of 2006. We estimate the seismic moment (M0) and spectral corner frequency (f0) using a spectral ratio approach for events with a high signal-to-noise (SNR) ratio that have a cross-correlation coefficient of 0.8 or greater with at least five other events. A cluster analysis of cross-correlation values indicates that the group of 421 events meeting the SNR and cross-correlation criteria forms eight event families that exhibit largely self-similar scaling. We estimate the M0 and f0 values of the 421 events and calculate their static stress drop and scaled energy (ER/M0) values. The estimated values suggest self-similar scaling within families, as well as between five of eight families (i.e.,  and  constant). We speculate that differences in scaled energy values for the two families with variable scaling may result from a lack of resolution in the velocity model. The observation of self-similar scaling is the first of its kind for such a large group of low-frequency volcanic tectonic events occurring during a single active dome extrusion eruption.

Liftoff of the 18 May 1980 surge of Mount St. Helens (USA) and the deposits left behind

Science.gov (United States)

Gardner, James E.; Andrews, Benjamin J.; Dennen, Robert

2017-01-01

The distance that ground-hugging pyroclastic density currents travel is limited partly by when they reverse buoyancy and liftoff into the atmosphere. It is not clear, however, what deposits are left behind by lofting flows. One current that was seen to liftoff was the surge erupted from Mount St. Helens on the morning of 18 May 1980. Before lofting, it had leveled a large area of thick forest (the blowdown zone). The outer edge of the devastated area—where trees were scorched but left standing (the scorched zone)—is where the surge is thought to have lifted off. Deposits in the outer parts of the blowdown and in the scorched zone were examined at 32 sites. The important finding is that the laterally moving surge traveled through the scorched zone, and hence, the change in tree damage does not mark the runout distance of the surge. Buoyancy reversal and liftoff are thus not preserved in the deposits where the surge lofted upwards. We propose, based on interpretation of eyewitness accounts and the impacts of the surge on trees and vehicles, that the surge consisted of a faster, dilute "overcurrent" and a slower "undercurrent," where most of the mass (and heat) was retained. Reasonable estimates for flow density and velocity show that dynamic pressure of the surge (i.e., its ability to topple trees) peaked near the base of the overcurrent. We propose that where the overcurrent began to liftoff, the height of peak dynamic pressure rose above the trees and stopped toppling them. The slower undercurrent continued forward, however, scorching trees, but lacked the dynamic pressure needed to topple them. Grain-size variations argue that it slowed from ˜30 m s-1 when it entered the scorched zone to ˜3 m s-1 at the far end.

Monitoring lava-dome growth during the 2004-2008 Mount St. Helens, Washington, eruption using oblique terrestrial photography

Science.gov (United States)

Major, J.J.; Dzurisin, D.; Schilling, S.P.; Poland, Michael P.

2009-01-01

We present an analysis of lava dome growth during the 2004–2008 eruption of Mount St. Helens using oblique terrestrial images from a network of remotely placed cameras. This underutilized monitoring tool augmented more traditional monitoring techniques, and was used to provide a robust assessment of the nature, pace, and state of the eruption and to quantify the kinematics of dome growth. Eruption monitoring using terrestrial photography began with a single camera deployed at the mouth of the volcano's crater during the first year of activity. Analysis of those images indicates that the average lineal extrusion rate decayed approximately logarithmically from about 8 m/d to about 2 m/d (± 2 m/d) from November 2004 through December 2005, and suggests that the extrusion rate fluctuated on time scales of days to weeks. From May 2006 through September 2007, imagery from multiple cameras deployed around the volcano allowed determination of 3-dimensional motion across the dome complex. Analysis of the multi-camera imagery shows spatially differential, but remarkably steady to gradually slowing, motion, from about 1–2 m/d from May through October 2006, to about 0.2–1.0 m/d from May through September 2007. In contrast to the fluctuations in lineal extrusion rate documented during the first year of eruption, dome motion from May 2006 through September 2007 was monotonic (± 0.10 m/d) to gradually slowing on time scales of weeks to months. The ability to measure spatial and temporal rates of motion of the effusing lava dome from oblique terrestrial photographs provided a significant, and sometimes the sole, means of identifying and quantifying dome growth during the eruption, and it demonstrates the utility of using frequent, long-term terrestrial photography to monitor and study volcanic eruptions.

Volcanic tremor masks its seismogenic source: Results from a study of noneruptive tremor recorded at Mount St. Helens, Washington

Science.gov (United States)

Denlinger, Roger P.; Moran, Seth C.

2014-01-01

On 2 October 2004, a significant noneruptive tremor episode occurred during the buildup to the 2004–2008 eruption of Mount St. Helens (Washington). This episode was remarkable both because no explosion followed, and because seismicity abruptly stopped following the episode. This sequence motivated us to consider a model for volcanic tremor that does not involve energetic gas release from magma but does involve movement of conduit magma through extension on its way toward the surface. We found that the tremor signal was composed entirely of Love and Rayleigh waves and that its spectral bandwidth increased and decreased with signal amplitude, with broader bandwidth signals containing both higher and lower frequencies. Our modeling results demonstrate that the forces giving rise to this tremor were largely normal to conduit walls, generating hybrid head waves along conduit walls that are coupled to internally reflected waves. Together these form a crucial part of conduit resonance, giving tremor wavefields that are largely a function of waveguide geometry and velocity. We find that the mechanism of tremor generation fundamentally masks the nature of the seismogenic source giving rise to resonance. Thus multiple models can be invoked to explain volcanic tremor, requiring that information from other sources (such as visual observations, geodesy, geology, and gas geochemistry) be used to constrain source models. With concurrent GPS and field data supporting rapid rise of magma, we infer that tremor resulted from drag of nearly solid magma along rough conduit walls as magma was forced toward the surface.

After the disaster: the hydrogeomorphic, ecological, and biological responses to the 1980 eruption of Mount St. Helens, Washington

Science.gov (United States)

Major, Jon J.; Crisafulli, Charlie; Bishop, John

2009-01-01

The 1980 eruption of Mount St. Helens caused instantaneous landscape disturbance on a grand scale. On 18 May 1980, an ensemble of volcanic processes, including a debris avalanche, a directed pyroclastic density current, voluminous lahars, and widespread tephra fall, abruptly altered landscape hydrology and geomorphology, and created distinctive disturbance zones having varying impacts on regional biota. Response to the geological and ecological disturbances has been varied and complex. In general, eruption-induced alterations in landscape hydrology and geomorphology led to enhanced stormflow discharge and sediment transport. Although the hydrological response to landscape perturbation has diminished, enhanced sediment transport persists in some basins. In the nearly 30 years since the eruption, 350 million (metric) tons of suspended sediment has been delivered from the Toutle River watershed to the Cowlitz River (roughly 40 times the average annual preeruption suspended-sediment discharge of the Columbia River). Such prodigious sediment loading has wreaked considerable socioeconomic havoc, causing significant channel aggradation and loss of flood conveyance capacity. Significant and ongoing engineering efforts have been required to mitigate these problems. The overall biological evolution of the eruption-impacted landscape can be viewed in terms of a framework of survivor legacies. Despite appearances to the contrary, a surprising number of species survived the eruption, even in the most heavily devastated areas. With time, survivor “hotspots” have coalesced into larger patches, and have served as stepping stones for immigrant colonization. The importance of biological legacies will diminish with time, but the intertwined trajectories of geophysical and biological successions will influence the geological and biological responses to the 1980 eruption for decades to come.

Array-Based Receiver Function Analysis of the Subducting Juan de Fuca Plate Beneath the Mount St. Helens Region and its Implications for Subduction Geometry and Metamorphism

Science.gov (United States)

Mann, M. E.; Abers, G. A.; Creager, K. C.; Ulberg, C. W.; Crosbie, K.

2017-12-01

Mount St. Helens (MSH) is unusual as a prolific arc volcano located 50 km towards the forearc of the main Cascade arc. The iMUSH (imaging Magma Under mount St. Helens) broadband deployment featured 70 seismometers at 10-km spacing in a 50-km radius around MSH, spanning a sufficient width for testing along-strike variation in subsurface geometry as well as deep controls on volcanism in the Cascade arc. Previous estimates of the geometry of the subducting Juan de Fuca (JdF) slab are extrapolated to MSH from several hundred km to the north and south. We analyze both P-to-S receiver functions and 2-D Born migrations of the full data set to locate the upper plate Moho and the dip and depth of the subducting slab. The strongest coherent phase off the subducting slab is the primary reverberation (Ppxs; topside P-to-S reflection) from the Moho of the subducting JdF plate, as indicated by its polarity and spatial pattern. Migration images show a dipping low velocity layer at depths less than 50 km that we interpret as the subducting JdF crust. Its disappearance beyond 50 km depth may indicate dehydration of subducting crust or disruption of high fluid pressures along the megathrust. The lower boundary of the low velocity zone, the JdF Moho, persists in the migration image to depths of at least 90 km and is imaged at 74 km beneath MSH, dipping 23 degrees. The slab surface is 68 km beneath MSH and 85 km beneath Mount Adams volcano to the east. The JdF Moho exhibits 10% velocity contrasts as deep as 85 km, an observation difficult to reconcile with simple models of crustal eclogitization. The geometry and thickness of the JdF crust and upper plate Moho is consistent with similar transects of Cascadia and does not vary along strike beneath iMUSH, indicating a continuous slab with no major disruption. The upper plate Moho is clear on the east side of the array but it disappears west of MSH, a feature we interpret as a result of both serpentinization of the mantle wedge and a

Source mechanisms of persistent shallow earthquakes during eruptive and non-eruptive periods between 1981 and 2011 at Mount St. Helens, Washington

Science.gov (United States)

Lehto, Heather L.; Roman, Diana C.; Moran, Seth C.

2013-01-01

Shallow seismicity between 0 and 3-km depth has persisted at Mount St. Helens, Washington (MSH) during both eruptive and non-eruptive periods for at least the past thirty years. In this study we investigate the source mechanisms of shallow volcano-tectonic (VT) earthquakes at MSH by calculating high-quality hypocenter locations and fault plane solutions (FPS) for all VT events recorded during two eruptive periods (1981–1986 and 2004–2008) and two non-eruptive periods (1987–2004 and 2008–2011). FPS show a mixture of normal, reverse, and strike-slip faulting during all periods, with a sharp increase in strike-slip faulting observed in 1987–1997 and an increase in normal faulting in 1998–2004. FPS P-axis orientations show a ~ 90° rotation with respect to regional σ1 (N23°E) during 1981–1986 and 2004–2008, bimodal orientations (~ N-S and ~ E-W) during 1987–2004, and bimodal orientations at ~ N-E and ~ S-W from 2008–2011. We interpret these orientations to likely be due to pressurization accompanying the shallow intrusion and subsequent eruption of magma as domes during 1981–1986 and 2004–2008 and the buildup of pore pressure beneath a seismogenic volume (located at 0–1 km) with a smaller component due to the buildup of tectonic forces during 1987–2004 and 2008–2011.

High-resolution digital elevation model of Mount St. Helens crater and upper North Fork Toutle River basin, Washington, based on an airborne lidar survey of September 2009

Science.gov (United States)

Mosbrucker, Adam

2014-01-01

The lateral blast, debris avalanche, and lahars of the May 18th, 1980, eruption of Mount St. Helens, Washington, dramatically altered the surrounding landscape. Lava domes were extruded during the subsequent eruptive periods of 1980–1986 and 2004–2008. More than three decades after the emplacement of the 1980 debris avalanche, high sediment production persists in the North Fork Toutle River basin, which drains the northern flank of the volcano. Because this sediment increases the risk of flooding to downstream communities on the Toutle and Cowlitz Rivers, the U.S. Army Corps of Engineers (USACE), under the direction of Congress to maintain an authorized level of flood protection, built a sediment retention structure on the North Fork Toutle River in 1989 to help reduce this risk and to prevent sediment from clogging the shipping channel of the Columbia River. From September 16–20, 2009, Watershed Sciences, Inc., under contract to USACE, collected high-precision airborne lidar (light detection and ranging) data that cover 214 square kilometers (83 square miles) of Mount St. Helens and the upper North Fork Toutle River basin from the sediment retention structure to the volcano's crater. These data provide a digital dataset of the ground surface, including beneath forest cover. Such remotely sensed data can be used to develop sediment budgets and models of sediment erosion, transport, and deposition. The U.S. Geological Survey (USGS) used these lidar data to develop digital elevation models (DEMs) of the study area. DEMs are fundamental to monitoring natural hazards and studying volcanic landforms, fluvial and glacial geomorphology, and surface geology. Watershed Sciences, Inc., provided files in the LASer (LAS) format containing laser returns that had been filtered, classified, and georeferenced. The USGS produced a hydro-flattened DEM from ground-classified points at Castle, Coldwater, and Spirit Lakes. Final results averaged about five laser last

Geology, petrology, and petrogenesis of Little Barrier Island, Hauraki Gulf, New Zealand

International Nuclear Information System (INIS)

Lindsay, J.M.; Worthington, T.J.; Smith, I.E.M.; Black, P.M.

1999-01-01

Little Barrier Island is the emergent part of a large, isolated, dacite-rhyodacite volcano in the active Hauraki Rift, 80 km northeast of Auckland. Two volcanic episodes are recognised: Waimaomao Formation was emplaced as a rhyodacite dome at 3 Ma, whereas the more extensive dacitic lavas of Haowhenua Formation were erupted between 1.2 and 1.6 Ma. All Little Barrier lavas are strongly porphyritic and contain phenocrysts of plagioclase, orthopyroxene, and hornblende. Geochemically, they are subduction related and distinct from the older lavas of the Coromandel Volcanic Group, being Zr rich but Rb and Ba poor. Their Sr and Nd isotope ratios are similar to those of the Tonga-Kermadec arc volcanoes. Modelling of the dacite supports petrographic evidence that recharge and mixing were important in the magmatic system. Little Barrier and two dacite domes of similar age and composition near Whangarei form a northwest-trending lineament subparallel to the Alexandra Volcanics and the Vening Meinesz Fracture Zone. (author). 49 refs., 13 figs., 5 tabs

The crustal magma storage system of Volcán Quizapu, Chile, and the effects of magma mixing on magma diversity

Science.gov (United States)

Bergantz, George W.; Cooper, Kari M.; Hildreth, Edward; Ruprecht, Phillipp

2012-01-01

Crystal zoning as well as temperature and pressure estimates from phenocryst phase equilibria are used to constrain the architecture of the intermediate-sized magmatic system (some tens of km3) of Volcán Quizapu, Chile, and to document the textural and compositional effects of magma mixing. In contrast to most arc magma systems, where multiple episodes of open-system behavior obscure the evidence of major magma chamber events (e.g. melt extraction, magma mixing), the Quizapu magma system shows limited petrographic complexity in two large historical eruptions (1846–1847 and 1932) that have contrasting eruptive styles. Quizapu magmas and peripheral mafic magmas exhibit a simple binary mixing relationship. At the mafic end, basaltic andesite to andesite recharge magmas complement the record from peripheral cones and show the same limited range of compositions. The silicic end-member composition is almost identical in both eruptions of Quizapu. The effusive 1846–1847 eruption records significant mixing between the mafic and silicic end-members, resulting in hybridized andesites and mingled dacites. These two compositionally simple eruptions at Volcán Quizapu present a rare opportunity to isolate particular aspects of magma evolution—formation of homogeneous dacite magma and late-stage magma mixing—from other magma chamber processes. Crystal zoning, trace element compositions, and crystal-size distributions provide evidence for spatial separation of the mafic and silicic magmas. Dacite-derived plagioclase phenocrysts (i.e. An25–40) show a narrow range in composition and limited zonation, suggesting growth from a compositionally restricted melt. Dacite-derived amphibole phenocrysts show similar restricted compositions and furthermore constrain, together with more mafic amphibole phenocrysts, the architecture of the magmatic system at Volcán Quizapu to be compositionally and thermally zoned, in which an andesitic mush is overlain by a homogeneous dacitic

Flow Encountering Abrupt Topography

Science.gov (United States)

2013-09-30

Colin at the Coral Reef Research Foundation and Paul Collins, who has extensive experience with such data). Helen Reef Concerted UCTD measurements...sensors, weights , 45 m of line, and a float) which were arrayed around Helen Reef nominally on the 90-m isobath using Revelle’s workboat. Colin (CRRF...the main islands of Palau and diverts around the south and north ends of the island group (Figure 1, left and right; Section ). At Helen Reef and Toby

"Kuninganna" Tallinnas / Andri Maimets

Index Scriptorium Estoniae

Maimets, Andri, 1979-

2007-01-01

Tänasest on Sõpruse kinos Stephen Frearsi mängufilm "Kuninganna" ("The Queen") : stsenarist Peter Morgan : kuninganna Elizabeth II kehastab Helen Mirren, peaminister Tony Blair'i Michael Sheen. Lisatud andmed Helen Mirreni kohta

Better constraints on the size and volatile content of the Mount St. Helens magma reservoir following the end of the 2004-2008 eruption

Science.gov (United States)

Mastin, L. G.; Lisowski, M.; Beeler, N.; Roeloffs, E.

2008-12-01

The October 2004-January 2008 eruption of Mount St. Helens produced about 93 million cubic meters dense-rock equivalent (DRE) lava at a continuous rate that decreased monotonically from ~6 m3 s-1 to zero over its duration. From late October 2004 through the end of the eruption, continuous GPS stations around the mountain recorded inward deflation at a rate that dropped monotonically below the noise level by early 2007. The geodetic signal is consistent with a volume change Δ Vc of ~16-25M m3 in an ellipsoidal reservoir of volume Vc centered at ~9-14 km depth beneath the crater. Throughout the eruption we used physically based models to extrapolate trends in lava-dome volume and deflation, and to forecast the duration and final erupted volume, Ve, using assumed or geologically constrained values of Vc, average recharge rate R into the reservoir, and compressibilities of magma (Km = ( 1/ρ m )( ∂ ρ m /∂ p )) and of the reservoir (Kc = ( 1/Vc )( ∂ Vc /∂ p )), where ρ m is magma density and p is pressure). Curves that neglected recharge consistently under-predicted both the final duration and volume, while those that assumed a constant recharge rate predicted indefinite duration and volume. The fact that the eruption ended several months after deflation stopped suggests that the long-term average recharge was close to zero, or at least much less than the average eruption rate. The discrepancy between Ve (93M m3) and Δ VC (16-25M m3) can be accounted for by the elastic relation Ve /Δ Vc = ( 1 + Km /Kc ), with Km = 3 - 4 × 10- 10 Pa-1 calculated for reservoir magma with 1- 1.5% bubbles (constrained from gas studies of the erupted lava), and Kc = 1.1 - 1.5 × 10 - 10 Pa-1. Assuming that the pressure drop dp in the reservoir was only slightly greater than the ~5 MPa increase in pressure at the 2004 vent elevation due to growth of the 220-m-high lava dome, the elastic relation Ve = VC dp( Kc + Km ) suggests that the eruption could have been fed by a reservoir

Tants / Eduard Tido, Janika Sarantshina ; interv. Mel Shiffer

Index Scriptorium Estoniae

Tido, Eduard

2007-01-01

Oma harrastusest räägivad hip-hop tantsijad Eduard Tido, Janika Sharantshina, Eva Ottas, show-tantsija Helen Randmäe, club freestyle autor Monika Tuvi, dance hall'i maaletooja Helen Lõhmus ja breikar Marek Vetik

MOOC Blended learning ontwikkelen

NARCIS (Netherlands)

Verjans, Steven

2015-01-01

Presentatie over het ontwerpen van leeractiviteiten (learning design) tijdens de zesde live sessie van de MOOC Blended learning ontwikkelen. Met gebruikmaking van presentatiematerialen van Diana Laurillard, Grainne Conole, Helen Beetham, Jos Fransen, Pieter Swager, Helen Keegan, Corinne Weisgerber.

Assessing New and Old Methods in Paleomagnetic Paleothermometry: A Test Case at Mt. St. Helens, USA

Science.gov (United States)

Bowles, J. A.; Gerzich, D.; Jackson, M. J.

2017-12-01

Paleomagnetic data can be used to estimate deposit temperatures (Tdep) of pyroclastic density currents (PDCs). The typical method is to thermally demagnetize oriented lithic clasts incorporated into the PDC. If Tdep is less than the maximum Curie temperature (Tc), the clast is partially remagnetized in the PDC, and the unblocking temperature (Tub) at which this remagnetization is removed is an estimate of Tdep. In principle, juvenile clasts can also be used, and Tub-max is taken as the minimum Tdep. This all assumes blocking (Tb) and unblocking temperatures are equivalent and that the blocking spectrum remains constant through time. Recent evidence shows that Tc in many titanomagnetites is a strong function of thermal history due to a crystal-chemical reordering process. We therefore undertake a study designed to test some of these assumptions and to assess the extent to which the method may be biased by a Tb spectrum that shifts to higher T during cooling. We also explore a new magnetic technique that relies only on stratigraphic variations in Tc. Samples are from the May 18, 1980 PDCs at Mt. St. Helens, USA. Direct temperature measurements of the deposits were 297 - 367°C. At sites with oriented lithics, standard methods provide a Tdep range that overlaps with measured temperatures, but is systematically higher by a few 10s of °C. By contrast, pumice clasts all give Tdep_min estimates that greatly exceed lithic estimates and measured temperatures. We attribute this overestimate to two causes: 1) Tc and Tub systematically increase with depth as a result of the reordering process. This results in Tdep_min estimates that vary by 50°C and increase with depth. 2) MSH pumice is multi-domain, where Tub > Tb, resulting in a large overestimate in Tdep. At 5 sites, stratigraphic variations in Tc were conservatively interpreted in terms of Tdep as 300°C. More sophisticated modeling of the time-temperature-depth evolution of Tc allows us to place tighter constraints on

The Stars Belong to Everyone: The rhetorical practices of astronomer and science writer Dr. Helen Sawyer Hogg (1905--1993)

Science.gov (United States)

Cahill, Maria J.

Astronomer and science writer Dr. Helen Sawyer Hogg (University of Toronto) reached a variety of audiences through different rhetorical forms. She communicated to her colleagues through her scholarly writings; she reached out to students and the public through her Toronto Star newspaper column entitled "With the Stars," which she authored for thirty years; she wrote The Stars Belong to Everyone , a book that speaks to a lay audience; she hosted a successful television series entitled Ideas ; and she delivered numerous speeches at scientific conferences, professional women's associations, school programs, libraries, and other venues. Adapting technical information for different audiences is at the heart of technical communication, and Sawyer Hogg's work exemplifies adaptation as she moves from writing for the scientific community (as in her articles on globular cluster research) to science writing for lay audiences (as in her newspaper column, book, and script for her television series). Initially she developed her sense of audience through a male perspective informed largely by her scholarly work with two men (Harlow Shapley and her husband, Frank Hogg) as well as the pervasive masculine culture of academic science. This dissertation situates Sawyer Hogg in what is slowly becoming a canon of technical communication scholarship on female scientists. Toward this end, I discuss how she rhetorically engaged two different audiences, one scholarly and one popular, how Sawyer Hogg translated male dominated scientific rhetoric to writing for the public, and how science writing helped her achieve her professional goals. Complementing the archival research in addressing the questions of this study, I employ social construction analysis (also known as the social perspective) for my research methodology. She was ahead of her time and embodied the social perspective years before its definition as a rhetorical concept. In short, my study illuminates one scientific woman's voice

Outcomes From the First Helene Fuld Health Trust National Institute for Evidence-Based Practice in Nursing and Healthcare Invitational Expert Forum.

Science.gov (United States)

Melnyk, Bernadette Mazurek; Gallagher-Ford, Lynn; Zellefrow, Cindy; Tucker, Sharon; Van Dromme, Laurel; Thomas, Bindu Koshy

2018-02-01

Even though multiple positive outcomes are the result of evidence-based care, including improvements in healthcare quality, safety, and costs, it is not consistently delivered by clinicians in healthcare systems throughout the world. In an attempt to accelerate the implementation of evidence-based practice (EBP) across the United States, an invitational Interprofessional National EBP Forum to determine major priorities for the advancement of EBP was held during the launch of the newly established Helene Fuld Health Trust National Institute for Evidence-Based Practice in Nursing and Healthcare at The Ohio State University College of Nursing. Interprofessional leaders from national organizations and federal agencies across the United States were invited to participate in the Forum. A pre-Forum survey was disseminated to participants to assess their perceptions of the state of EBP and actions necessary to speed the translation of research into real-world clinical settings. Findings from a pre-Forum survey (n = 47) indicated ongoing low implementation of EBP in U.S. healthcare settings. These findings were shared with leaders from 45 organizations and agencies who attended the Forum. Breakout groups on practice, education, implementation science, and policy discussed the findings and responded to a set of standardized questions. High-priority action tactics were identified, including the need for: (a) enhanced reimbursement for EBP, (b) more interprofessional education and skills building in EBP, and (c) leaders to prioritize EBP and fuel it with resources. The delivery of and reimbursement for evidence-based care must become a high national priority. Academic faculty across all healthcare disciplines need to teach EBP, healthcare systems must invest in EBP resources, and payers must attach reimbursement to care that is evidence-based. An action collaborative of the participating organizations has been formed to accelerate EBP across the United States to achieve the

Eestlanna püüab murda da Vinci koodi / Sash Uusjärv

Index Scriptorium Estoniae

Uusjärv, Sash

2010-01-01

Kadrioru Kunstimuuseumis eksponeeri 5.-12. veebruarini 2010. a. Leonardo da Vinci arvatavat autoportreed. Portree leiti 2008. aastal ühest Lõuna-Itaalia erakogust ja graafiline disainer Helen Kokk valmistas maali järgi arvutimudeli. Disainer Helen Kokka mõtteid tööprotsessitst

The Archaen volcanic facies in the Migori segment, Nyanza greenstone belt, Kenya: stratigraphy, geochemistry and mineralisation

Science.gov (United States)

Ichang'l, D. W.; MacLean, W. H.

The Migori segment is an 80 by 20 km portion of the Nyanza greenstone belt which forms the northern part of the Archean Tanzanian Craton in western Kenya, northern Tanzania and southeastern Uganda. It consists of two volcanic centres, each with central, proximal and distal volcanic facies, comprising the Migori Group, the Macalder and Lolgorien Subgroups, and eleven volcano-sedimentary formations. The centres are separated by a basin of tuffs and greywacke turbidites. The volcanics are bimodal mafic basalt and dolerite ( Zr/Y = 3.8 - 6.5, La N/Yb N = 1.0 - 2.4) , and felsic calc-alkaline dacite-rhyolite ( Zr/Y = 10 - 21, La N/Yb N = 19 - 42 ) and high-K dacite ( Zr/Y = 9 - 16, La N/Yb N = 21 - 22 ). Felsic units form approximately three-fourths of the volcanic stratigraphy. Basalts, calc-alkaline dacites and rhyolites were deposited in a submarine environment, but the voluminous high-K dacites were erupted subaerially. The turbidites contain units of iron-formations. Granitic intrusions are chemically continuous with the high-K dacites. The felsic volcanics are anologous to those found at modern volcanic arc subduction settings involving continental crust. The Macalder ZnCuAuAg volcanogenic massive sulphide deposits is in central facies basalts-greywacke-rhyolite. Gold mineralisation occurs in proximal facies tuffs and iron formation, and in oblique and semi-conformable quartz veins. Greenstones in the Nyanza belt are dominated by calc-alkaline felsic volcanics in constrast to the komatiite-tholeiitic basalt volcanism in the Kaapvaal Craton of South Africa, and a mixture of the two types in the Zimbabwe Craton.

The Laramide Mesa formation and the Ojo de Agua caldera, southeast of the Cananea copper mining district, Sonora, Mexico

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Cox, Dennis P.; Miller, Robert J.; Woodbourne, Keith L.

2006-01-01

The Mesa Formation extends from Cananea, Mexico, southeast to the Sonora River and is the main host rock of Laramide porphyry copper deposits in the Cananea District and at the Alacran porphyry prospect to the east. The Mesa consists of two members-a lower andesite and an upper dacite. The lowest part of the dacite member is a crystal tuff about 100 m thick. This tuff is the outfall of a caldera centered near the village of Ojo de Agua, dated by 40Ar/39Ar at 65.8 Ma ?0.4. The Ojo de Agua Caldera is about 9 km in diameter and is filled by a light gray biotite dacite tuff with abundant flattened pumice fragments. The volume of the caldera is estimated to be 24 km3.

Runout distance and dynamic pressure of pyroclastic density currents: Evidence from 18 May 1980 blast surge of Mount St. Helens

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Gardner, J. E.; Andrews, B. J.

2016-12-01

Pyroclastic density currents (flows and surges) are one of the most deadly hazards associated with volcanic eruptions. Understanding what controls how far such currents will travel, and how their dynamic pressure evolves, could help mitigate their hazards. The distance a ground hugging, pyroclastic density current travels is partly limited by when it reverses buoyancy and lifts off into the atmosphere. The 1980 blast surge of Mount St. Helens offers an example of a current seen to lift off. Before lofting, it had traveled up to 20 km and leveled more than 600 km3 of thick forest (the blowdown zone). The outer edge of the devastated area - where burned trees that were left standing (the singe zone) - is where the surge is thought to have lifted off. We recently examined deposits in the outer parts of the blowdown and in the singe zone at 32 sites. The important finding is that the laterally moving surge travelled into the singe zone, and hence the change in tree damage does not mark the run out distance of the ground hugging surge. Eyewitness accounts and impacts on trees and vehicles reveal that the surge consisted of a fast, dilute "overcurrent" and a slower "undercurrent", where most of the mass (and heat) was retained. Reasonable estimates for flow density and velocity show that dynamic pressure of the surge (i.e., its ability to topple trees) peaked near the base of the overcurrent. We propose that when the overcurrent began to lift off, the height of peak dynamic pressure rose above the trees and stopped toppling them. The slower undercurrent continued forward, burning trees but it lacked the dynamic pressure needed to topple them. Grain-size variations argue that it slowed from 30 m/s when it entered the singe zone to 3 m/s at the far end. Buoyancy reversal and liftoff are thus not preserved in the deposits where the surge lofted upwards.

[Volcanoes: A Compilation of Four Articles Appearing in Issues of "Instructor,""Science and Children," and "Science Teacher" Magazines in September 1980 and March 1981.

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San Mateo County Office of Education, Redwood City, CA. SMERC Information Center.

This compilation of four journal articles (Instructor, September 1980; Science and Children, September 1980; and Science Teacher, September 1980 and March 1981) focuses on volcanoes, particularly Mount St. Helens in Oregon. The first article, "The Earth is Alive!" describes the eruptions of Mount St. Helens, provides basic information on…

Upper Carboniferous retroarc volcanism with submarine and subaerial facies at the western Gondwana margin of Argentina

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Koukharsky, M.; Kleiman, L.; Etcheverría, M.; Quenardelle, S.; Bercowski, F.

2009-04-01

During Late Carboniferous times a continental magmatic arc developed at the western margin of Gondwana in South America, as several marine sedimentary basins were formed at the same time in the retroarc region. North of 33°S, at Cordón Agua del Jagüel, Precordillera of Mendoza, Argentina, a volcanic sequence crops out which was emplaced in a submarine environment with some subaerial exposures, and it is intercalated in marine sediments of Agua del Jagüel Formation, which fills of one of these retroarc basins. This paper presents, for the first time, a facies analyses together with geochemical and isotopic data of this volcanic suite, suggesting its deposition in an ensialic retroarc marine basin. The volcanic succession comprises debris flows with either sedimentary or volcanic fragments, base surge, resedimented massive and laminated dacitic-andesitic hyaloclastite, pillow lava, basic hyaloclastite and dacitic-andesitic lavas and hyaloclastite facies. Its composition is bimodal, either basaltic or dacitic-andesitic. The geochemistry data indicate a subalkaline, low K calk-alkaline and metaluminous affinity. The geochemistry of the basalts points to an origin of the magmas from a depleted mantle source with some crustal contamination. Conversely, the geochemistry of the dacites-andesites shows an important participation of both crustal components and subduction related fluids. A different magmatic source for the basalts than for the dacites-andesites is also supported by Sr and Nd isotopic initial ratios and Nd model ages. The characteristics of this magmatic suite suggest its emplacement in an extensional setting probably associated with the presence of a steepened subduction zone at this latitude during Upper Carboniferous times.

Source mechanism of small long-period events at Mount St. Helens in July 2005 using template matching, phase-weighted stacking, and full-waveform inversion

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Matoza, Robin S.; Chouet, Bernard A.; Dawson, Phillip B.; Shearer, Peter M.; Haney, Matthew M.; Waite, Gregory P.; Moran, Seth C.; Mikesell, T. Dylan

2015-01-01

Long-period (LP, 0.5-5 Hz) seismicity, observed at volcanoes worldwide, is a recognized signature of unrest and eruption. Cyclic LP “drumbeating” was the characteristic seismicity accompanying the sustained dome-building phase of the 2004–2008 eruption of Mount St. Helens (MSH), WA. However, together with the LP drumbeating was a near-continuous, randomly occurring series of tiny LP seismic events (LP “subevents”), which may hold important additional information on the mechanism of seismogenesis at restless volcanoes. We employ template matching, phase-weighted stacking, and full-waveform inversion to image the source mechanism of one multiplet of these LP subevents at MSH in July 2005. The signal-to-noise ratios of the individual events are too low to produce reliable waveform-inversion results, but the events are repetitive and can be stacked. We apply network-based template matching to 8 days of continuous velocity waveform data from 29 June to 7 July 2005 using a master event to detect 822 network triggers. We stack waveforms for 359 high-quality triggers at each station and component, using a combination of linear and phase-weighted stacking to produce clean stacks for use in waveform inversion. The derived source mechanism pointsto the volumetric oscillation (~10 m3) of a subhorizontal crack located at shallow depth (~30 m) in an area to the south of Crater Glacier in the southern portion of the breached MSH crater. A possible excitation mechanism is the sudden condensation of metastable steam from a shallow pressurized hydrothermal system as it encounters cool meteoric water in the outer parts of the edifice, perhaps supplied from snow melt.

Magmatic controls on eruption dynamics of the 1950 yr B.P. eruption of San Antonio Volcano, Tacaná Volcanic Complex, Mexico-Guatemala

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Mora, Juan Carlos; Gardner, James Edward; Macías, José Luis; Meriggi, Lorenzo; Santo, Alba Patrizia

2013-07-01

San Antonio Volcano, in the Tacaná Volcanic Complex, erupted ~ 1950 yr. B.P., with a Pelean type eruption that produced andesitic pyroclastic surges and block-and-ash flows destroying part of the volcano summit and producing a horse-shoe shaped crater open to the SW. Between 1950 and 800 yr B.P. the eruption continued with effusive andesites followed by a dacite lava flow and a summit dome, all from a single magma batch. All products consist of phenocrysts and microphenocrysts of zoned plagioclase, amphibole, pyroxene, magnetite ± ilmenite, set in partially crystallized groundmass of glass and microlites of the same mineral phases, except for the lack of amphibole. Included in the andesitic blocks of the block-and-ash flow deposit are basaltic andesite enclaves with elongated and ellipsoidal forms and chilled margins. The enclaves have intersertal textures with brown glass between microphenocrysts of plagioclase, hornblende, pyroxene, and olivine, and minor proportions of phenocrysts of plagioclase, hornblende, and pyroxene. A compositional range obtained of blocks and enclaves resulted from mixing between andesite (866 °C ± 22) and basaltic andesite (enclaves, 932 °C ± 22), which may have triggered the explosive Pelean eruption. Vestiges of that mixing are preserved as complex compositional zones in plagioclase and clinopyroxene-rich reaction rims in amphibole in the andesite. Whole-rock chemistry, geothermometry, experimental petrology and modeling results suggest that after the mixing event the eruption tapped hybrid andesitic magma (≤ 900 °C) and ended with effusive dacitic magma (~ 825 °C), all of which were stored at ~ 200 MPa water pressure. A complex open-system evolution that involved crustal end-members best explains the generation of effusive dacite from the hybrid andesite. Amphibole in the dacite is rimmed by reaction products of plagioclase, orthopyroxene, and Fe-Ti oxides produced by decompression during ascent. Amphibole in the andesite

Eruptive history of Mount Katmai, Alaska

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Hildreth, Edward; Fierstein, Judith

2012-01-01

Mount Katmai has long been recognized for its caldera collapse during the great pyroclastic eruption of 1912 (which vented 10 km away at Novarupta in the Valley of Ten Thousand Smokes), but little has previously been reported about the geology of the remote ice-clad stratovolcano itself. Over several seasons, we reconnoitered all parts of the edifice and sampled most of the lava flows exposed on its flanks and caldera rim. The precipitous inner walls of the 1912 caldera remain too unstable for systematic sampling; so we provide instead a photographic and interpretive record of the wall sequences exposed. In contrast to the several andesite-dacite stratovolcanoes nearby, products of Mount Katmai range from basalt to rhyolite. Before collapse in 1912, there were two overlapping cones with separate vent complexes and craters; their products are here divided into eight sequences of lava flows, agglutinates, and phreatomagmatic ejecta. Latest Pleistocene and Holocene eruptive units include rhyodacite and rhyolite lava flows along the south rim; a major 22.8-ka rhyolitic plinian fall and ignimbrite deposit; a dacite-andesite zoned scoria fall; a thick sheet of dacite agglutinate that filled a paleocrater and draped the west side of the edifice; unglaciated leveed dacite lava flows on the southeast slope; and the Horseshoe Island dacite dome that extruded on the caldera floor after collapse. Pre-collapse volume of the glaciated Katmai edifice was ∼30 km3, and eruptive volume is estimated to have been 57±13 km3. The latter figure includes ∼40±6 km3 for the edifice, 5±2 km3 for off-edifice dacite pyroclastic deposits, and 12±5 km3 for the 22.8-ka rhyolitic pyroclastic deposits. To these can be added 13.5 km3 of magma that erupted at Novarupta in 1912, all or much of which is inferred to have been withdrawn from beneath Mount Katmai. The oldest part of the edifice exposed is a basaltic cone, which gave a 40Ar/39Ar plateau age of 89 ± 25 ka.

36 CFR 264.11 - Use of symbol.

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2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Use of symbol. 264.11 Section... MANAGEMENT Mount St. Helens National Volcanic Monument Symbol § 264.11 Use of symbol. Except as provided in § 264.12, use of the Mount St. Helens National Volcanic Monument official symbol, including a facsimile...

76 FR 11985 - Acquisition Regulation: Department of Energy Acquisition Regulation, Government Property

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2011-03-04

.... Comments by e-mail are encouraged. FOR FURTHER INFORMATION CONTACT: Helene Abbott at (202) 287-1593 or via e-mail: helene.abbott@hq.doe.gov . SUPPLEMENTARY INFORMATION: Background Section-by-Section Analysis... the Idaho National Lab and has been in use since the late 1990s. The PIDS system is used by both DOE...

Sr–Nd isotopic compositions of Paleoproterozoic metavolcanic rocks from the southern Ashanti volcanic belt, Ghana

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Dampare, Samuel; Shibata, Tsugio; Asiedu, Daniel; Okano, Osamu; Manu, Johnson; Sakyi, Patrick

2009-01-01

Neodymium (Nd) and strontium (Sr) isotopic data are presented for Paleoproterozoic metavolcanic rocks in the southern part of the Ashanti volcanic belt of Ghana. The metavolcanic rocks are predominantly basalts/basaltic andesites and andesites with minor dacites. Two types of basalts/basaltic andesites (B/A), Type I and Type II, have been identified. The Type I B/A are stratigraphically overlain by the Type II B/A, followed by the andesites and the dacites. The analyzed volcanic rocks commonl...

The plinian eruptions of 1912 at Novarupta, Katmai National Park, Alaska

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Fierstein, J.; Hildreth, W.

1992-01-01

The three-day eruption at Novarupta in 1912 consisted of three discrete episodes. Episode I began with plinian dispersal of rhyolitic fallout (Layer A) and contemporaneous emplacement of rhyolitic ignimbrites and associated proximal veneers. The plinian column was sustained throughout most of the interval of ash flow generation, in spite of progressive increases in the proportions of dacitic and andesitic ejecta at the expense of rhyolite. Accordingly, plinian Layer B, which fell in unbroken continuity with purely rhyolitic Layer A, is zoned from >99% to ???15% rhyolite and accumulated synchronously with emplacement of the correspondingly zoned ash flow sequence in Mageik Creek and the Valley of Ten Thousand Smokes (VTTS). Only the andesiterichest flow units that cap the flow sequence lack a widespread fallout equivalent, indicating that ignimbrite emplacement barely outlasted the plinian phase. On near-vent ridges, the passing ash flows left proximal ignimbrite veneers that share the compositional zonation of their valley-filling equivalents but exhibit evidence for turbulent deposition and recurrent scour. Episode II began after a break of a few hours and was dominated by plinian dispersal of dacitic Layers C and D, punctuated by minor proximal intraplinian flows and surges. After another break, dacitic Layers F and G resulted from a third plinian episode (III); intercalated with these proximally are thin intraplinian ignimbrites and several andesite-rich fall/flow layers. Both CD and FG were ejected from an inner vent much as 0.4 km3 of rhyolitic glass shards from eruptive Episode I fell with CDE and 1.1 km3 with FGH. Most of the rhyolitic ash in the dacitic fallout layers fell far downwind (SE of the vent); near the rhyolite-dominated ignimbrite, however, nearly all of Layers E and H are dacitic, showing that the downwind rhyolitic ash is of 'co-plinian' rather than co-ignimbrite origin. ?? 1992 Springer-Verlag.

The compositionally zoned eruption of 1912 in the Valley of Ten Thousand Smokes, Katmai National Park, Alaska

Science.gov (United States)

Hildreth, W.

1983-01-01

On June 6-8, 1912, ??? 15 km3 of magma erupted from the Novarupta caldera at the head of the Valley of Ten Thousand Smokes (VTTS), producing ??? 20 km3 of air-fall tephra and 11-15 km3 of ash-flow tuff within ??? 60 hours. Three discrete periods of ash-fall at Kodiak correlate, respectively, with Plinian tephra layers designated A, CD, and FG by Curtis (1968) in the VTTS. The ash-flow sequence overlapped with but outlasted pumice fall A, terminating within 20 hours of the initial outbreak and prior to pumice fall C. Layers E and H consist mostly of vitric dust that settled during lulls, and Layer B is the feather edge of the ash flow. The fall units filled and obscured the caldera, but arcuate and radial fissures outline a 6-km2 depression. The Novarupta lava dome and its ejecta ring were emplaced later within the depression. At Mt. Katmai, 10 km east of the 1912 vent, a 600-m-deep caldera of similar area also collapsed at about this time, probably owing to hydraulic connection with the venting magma system; but all known ejecta are thought to have erupted at Novarupta. Mingling of three distinctive magmas during the eruption produced an abundance of banded pumice, and mechanical mixing of chilled ejecta resulted in deposits with a wide range of bulk composition. Pumice in the initial fall unit (A) is 100% rhyolite, but fall units atop the ash flow are > 98% dacite; black andesitic scoria is common only in the ash flows and in near-vent air-fall tephra. Pumice counts show the first half of the ash-flow deposit to be 91-98% rhyolite, but progressive increases of dacite and andesite eventually reduced the rhyolitic component to 20 km to the lowermost VTTS, and deposited 1-8 m of debris there. Rhyolitic ejecta contain only 1-2% phenocrysts but andesite and dacite have 30-45%. Quartz is present and augite absent only in the rhyolite, but all ejecta contain plagioclase, orthopyroxene, titanomagnetite, ilmenite, apatite, and pyrrhotite; rare olivine occurs in the

The Chacana caldera complex in Ecuador

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Hall, Minard L; Mothes, Patricia A [Instituto Geofisico, Escuela Politecnica Nacional, Quito (Ecuador)], E-mail: volcan_pete@yahoo.com

2008-10-01

The Chacana caldera, located immediately east of Quito, capital of Ecuador, forms the most-northern edifice of Ecuadoros rhyolite province. It is a 50X30 km Pleistocene structure that has remained active into historic times. Vitrophyres, welded tuffs, and ignimbrites of rhyolitic and dacitic composition constitute the outer flanks, meantime syngenetic breccias and tuffs, capped later by extensive dacite lava flows and basin sediments, filled the calderaos depression. A notable resurgence occurred that lifted quiet-water sediments to over 4000 m in elevation. The area has numerous hot springs, and little seismic activity.

The Chacana caldera complex in Ecuador

International Nuclear Information System (INIS)

Hall, Minard L; Mothes, Patricia A

2008-01-01

The Chacana caldera, located immediately east of Quito, capital of Ecuador, forms the most-northern edifice of Ecuadoros rhyolite province. It is a 50X30 km Pleistocene structure that has remained active into historic times. Vitrophyres, welded tuffs, and ignimbrites of rhyolitic and dacitic composition constitute the outer flanks, meantime syngenetic breccias and tuffs, capped later by extensive dacite lava flows and basin sediments, filled the calderaos depression. A notable resurgence occurred that lifted quiet-water sediments to over 4000 m in elevation. The area has numerous hot springs, and little seismic activity.

Popmuusika / Helen Sildna

Index Scriptorium Estoniae

Sildna, Helen

2005-01-01

Uutest heliplaatidest Maxence Cyrin "Modern Rhapsodies", Mint Royale "See You In The Morning", Robbie Williams "Intesive", The Paddingtons "Fist Comes", Frank Sinatra With Tommy Dorsey "The Essential", Deep Purple "Rapture Of The Deep", Oleg Pissarenko "The Book's Burning"

Ignimbrite Analyses of Batur Caldera, Bali, based on 14C Dating

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Igan S. Sutawidjaja

2014-06-01

Full Text Available http://dx.doi.org/10.17014/ijog.vol4no3.20094The Batur Caldera, in the northeastern part of Bali Island, is an elliptical collapse structure 13.8 by 10 km in size and another circular composite collapse structure with a diameter of 7.5 km in its centre. Two stages of the collapse were interrupted by silicic andesite lavas and domes. The first collapse was initiated by the eruption of about 84 km3 of the dacitic "Ubud Ignimbrite", about 29,300 years B.P., which caused a steep-walled depression about 1 km deep. The second ignimbrite was erupted from a large crater about the present lake, and it  produced about 19 km3 of a similar voluminous dacitic ignimbrite, called the "Gunungkawi Ignimbrite" about 20,150 years B.P. This second eruption trig- gered a second collapse, which created the central circular caldera, and formed a basin structure. Both the Ubud and Gunungkawi Ignimbrites consist of a similar dacitic composition, white to red (the most abundant nearly 90 % and dark grey to black dacitic pumice clasts. The large clasts, up to 20 cm in diameter, are in the non-welded ignimbrite, particularly in the upper part of the Gunungkawi Ignimbrite. The intracaldera ignimbrite, called the "Batur Ignimbrite" about 5 km3  in volume is a densely welded ignimbrite and generally shows typical welded features. The ignimbrite comprises at least five different flow units, separated by thin (15 - 40 cm welded pumiceous airfall deposits, with flattened pumice clasts. Another large eruption occurred about 5,500 years B.P., producing around 0.09 km3  andesitic ignimbrite. This was initiated by phreatomagmatic eruptions, indicated by thick phreatomagmatic and surge deposits, underlying the ignimbrite. The caldera and its vicinity are partly filled, and variably mantled by later eruptive products of dacitic and andesitic phreatomagmatic and airfall deposits.  

The geology of Mount Taftan stratovolcano, southeast of Iran

International Nuclear Information System (INIS)

Biabangard, H.; Moradian, A.

2008-01-01

Mount Taftan is a double-peaked stratovolcano, located in southeast of Iran. This volcano constructed a number of calderas among which one of the most important is Anjerk. The magmas erupted from this multi-caldera complex range from andesi-basalt to dacite, but are dominated by andesite and dacite. Two terminal cones, Narkuh and Matherkuh, culminate at 4100 m and 3950 m, respectively. There are three evolutionary stages in the history of the volcanic complex (stage 1: Palaevolcanism, 6.95±0.72Ma, stage 2: Mesovolcanism, 6.01±0.15Ma and stage 3: Neo volcanism, 0.71± 0.03Ma). The eruptive products consist of lava flows, iguimbrites and pyroclastic rocks. The later include tuffs, nuees ardents, breccias and sometimes reworked as lahars. Textural and mineralogical data suggest that both magma mixing and fractional crystallization were involved in the generation of the andesites and dacites. The magmas erupted from this volcano show a calc-alkaline trend. The corresponding lavas are calk-alkaline with a potasic tendency.

Seismogenic frictional melting in the magmatic column as the driving force of stick-slip motion

Science.gov (United States)

Kendrick, J. E.; Lavallee, Y.; Hirose, T.; Di Toro, G.; Hornby, A.; De Angelis, S.; Henton De Angelis, S.; Ferk, A.; Hess, K.; Leonhardt, R.; Dingwell, D. B.

2013-12-01

Lava dome eruptions subjected to high extrusion rates commonly evolve from endogenous to exogenous growth and limits to their structural stability hold catastrophic potential as explosive eruption triggers. In the conduit strain localisation in magma, accompanied by seismogenic failure, marks the onset of brittle magma ascent dynamics. The rock record of exogenous dome structures preserves vestiges of cataclastic processes and of thermal anomalies, key to unravelling subsurface processes. A combined structural, thermal and magnetic investigation of shear bands from Mount St. Helens (MSH) and Soufrière Hills volcano (SHV) reveal evidence of faulting and frictional melting within the magmatic column. High velocity rotary shear (HVR) experiments demonstrate the propensity for melting of andesitic and dacitic material (from SHV and MSH respectively) at upper conduit stress conditions. Such melting events may be linked to the step-wise extrusion of magma accompanied by repetitive long-period (LP) seismicity. Using a source duration calculated from the waveforms at seismic stations around SHV, and slip distance per drumbeat calculated from extrusion rate, frictional melting of SHV andesite in a high velocity rotary shear apparatus can be achieved at small slip distances (HVR experiments which mimic rapid velocity fluctuations in stick-slip behavior demonstrate velocity-weakening behavior of melt, with a tendency for unstable slip. We postulate that pseudotachylyte generation could be the underlying cause of stick-slip motion and associated seismic 'drumbeats', which are so commonly observed at dome-building volcanoes, allowing for a fixed spatial locus and the occurrence of 'families' of similar seismic events. We conclude that, given the ease with which melting is achieved in volcanic rocks, and considering the high ambient temperatures in volcanic conduits, frictional melting is a highly probable consequence of viscous magma ascent.

(Southeast of Rayen, Kerman

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Leila Dargahi

2017-11-01

Full Text Available The Alishahi rhyodacitic-dacitic columnar joints are outcropped in the Middle-Upper Eocene Razak complex in the southeastern of Urumieh-Dokhtar volcanic belt in the Dehaj-Sarduieh volcano-sedimentary belt. The complex consists of intermittent of pyroclastic rocks, andesite, rhyolite, and rhyodacite-dacitic lava flows. The latter partially shows 5 to 6 unequal sided columnar structure in which entablature and colonnade sections along with stria are clearly visible. The predominant textures are phyritic, hyaloporphiritic, glomeroporphyritic, flow and sieve textures along with perlitic cracks. Mineralogically, the Alishahi rhyodacitic-dacitic rocks consist of plagioclase phenocrysts together with rare microphenocrysts of sanidine, orthoclase, hornblende, pyroxene, biotite and accessory minerals including apatite, titanite and opaques are setting in a cryptocrystalline glassy matrix. The matrix is partly in the verge of devitrification process and conversion to mixture of quartz and alkali feldspars. Geochemically, the Alishahi columnar joints are rhyodacitic-dacitic in composition with calc-alkaline nature. Negative Eu anomaly and decrease in Sr content along with increase in Si amount reveal the significance of plagioclase as a differentiated phase. Enrichment in large lithophile elements and depletion in high field strength elements normalized to primitive mantle such as Ti, Ta, Nb along with their chondrite normalized rare earth elements patterns are pointing to their magma formation in a volcanic arc setting in an active continental margin. The depletion in Nb and Ta could be related to their low solubility in aqueous fluids and melts formed under relatively low pressures in the shallow part of the subduction zone.

Topographic controls on pyroclastic density current dynamics: Insight from 18 May 1980 deposits at Mount St. Helens, Washington (USA)

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Brand, Brittany D.; Bendaña, Sylvana; Self, Stephen; Pollock, Nicholas

2016-07-01

Our ability to interpret the deposits of pyroclastic density currents (PDCs) is critical for understanding the transport and depositional processes that control PDC dynamics. This paper focuses on the influence of slope on flow dynamics and criticality as recorded in PDC deposits from the 18 May 1980 eruption of Mt. St. Helens (USA). PDC deposits are found along the steep flanks (10°-30°) and across the pumice plain ( 5°) up to 8 km north of the volcano. Granulometry, componentry and descriptions of depositional characteristics (e.g., bedform morphology) are recorded with distance from source. The pumice plain deposits are primarily thick (3-12 m), massive and poorly-sorted, and represent deposition from a series of concentrated PDCs. By contrast, the steep flank deposits are stratified to cross-stratified, suggesting deposition from PDCs where turbulence strongly influenced transport and depositional processes. We propose that acceleration of the concentrated PDCs along the steep flanks resulted in thinning of the concentrated, basal region of the current(s). Enhanced entrainment of ambient air, and autofluidization from upward fluxes of air from substrate interstices and plunging breakers across rugged, irregular topography further inflated the currents to the point that the overriding turbulent region strongly influenced transport and depositional mechanisms. Acceleration in combination with partial confinement in slot canyons and high surface roughness would also increase basal shear stress, further promoting shear and traction transport in the basal region of the current. Conditions along the steep flank resulted in supercritical flow, as recorded by regressive bedforms, which gradually transitioned to subcritical flow downstream as the concentrated basal region thickness increased as a function of decreasing slope and flow energy. We also find that (1) PDCs were erosive into the underlying granular substrate along high slopes (> 25°) where currents were

A closer look at the pyroclastic density current deposits of the May 18, 1980 eruption of Mt St Helens

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Mackaman-Lofland, C. A.; Brand, B. D.; Dufek, J.

2010-12-01

Pyroclastic Density Currents (PDCs) are the most dangerous hazard associated with explosive volcanic eruptions. Due to the danger associated with observing these ground-hugging currents of searing hot gas, ash, and rock in real time, their processes are poorly understood. In order to understand flow dynamics, including what controls how far PDCs travel and how they interact with topography, it is necessary to study their deposits. The May 18th, 1980 eruption of Mt. St. Helens produced multiple PDCs, burying the area north of the volcano under 10s of meters of PDC deposits. Because the eruption is one of the best observed on record, individual flow units can be correlated to changes in eruptive intensity throughout the day (e.g., Criswell, 1987). Deep drainage erosion over the past 30 years has exposed the three-dimensional structure of the PDC deposits, making this intensive study possible. Up to six flow units have been identified along the large western drainage of the pumice plain. Each flow unit has intricate vertical and lateral facies changes and complex cross-cutting relationships away from source. The most proximal PDC deposits associated with the afternoon flows on May 18 are exposed 4 km from source in tributaries of the large drainage on the western side of the pumice plain. Hummocks from the debris avalanche are also exposed above and within these proximal drainages. It is apparent that the PDCs were often erosional, entraining large blocks from the hummocks and depositing them in close proximity downstream. The currents were also depositional, as thick sequences of PDC deposits are found in areas between hummocks, which thin to veneers above them. This indicates that the currents were interacting with complex topography early in their propagation, and is reflected by spatially variable bed conditions including rapid changes in bedding and granulometry characteristics within individual flow units. For example, within 20 lateral meters of a given flow

Eruptive history of South Sister, Oregon Cascades

Science.gov (United States)

Fierstein, J.; Hildreth, W.; Calvert, A.T.

2011-01-01

South Sister is southernmost and highest of the Three Sisters, three geologically dissimilar stratovolcanoes that together form a spectacular 20km reach along the Cascade crest in Oregon. North Sister is a monotonously mafic edifice as old as middle Pleistocene, Middle Sister a basalt-andesite-dacite cone built between 48 and 14ka, and South Sister is a basalt-free edifice that alternated rhyolitic and intermediate modes from 50ka to 2ka (largely contemporaneous with Middle Sister). Detailed mapping, 330 chemical analyses, and 42 radioisotopic ages show that the oldest exposed South Sister lavas were initially rhyolitic ~50ka. By ~37ka, rhyolitic lava flows and domes (72-74% SiO2) began alternating with radially emplaced dacite (63-68% SiO2) and andesite (59-63% SiO2) lava flows. Construction of a broad cone of silicic andesite-dacite (61-64% SiO2) culminated ~30ka in a dominantly explosive sequence that began with crater-forming andesitic eruptions that left fragmental deposits at least 200m thick. This was followed at ~27ka by growth of a steeply dipping summit cone of agglutinate-dominated andesite (56-60.5% SiO2) and formation of a summit crater ~800m wide. This crater was soon filled and overtopped by a thick dacite lava flow and then by >150m of dacitic pyroclastic ejecta. Small-volume dacite lavas (63-67% SiO2) locally cap the pyroclastic pile. A final sheet of mafic agglutinate (54-56% SiO2) - the most mafic product of South Sister - erupted from and drapes the small (300-m-wide) present-day summit crater, ending a summit-building sequence that lasted until ~22ka. A 20kyr-long-hiatus was broken by rhyolite eruptions that produced (1) the Rock Mesa coulee, tephra, and satellite domelets (73.5% SiO2) and (2) the Devils Chain of ~20 domes and short coulees (72.3-72.8% SiO2) from N-S vent alignments on South Sister's flanks. The compositional reversal from mafic summit agglutinate to recent rhyolites epitomizes the frequently changing compositional modes of the

N-P Co-Limitation of Primary Production and Response of Arthropods to N and P in Early Primary Succession on Mount St. Helens Volcano

Science.gov (United States)

Bishop, John G.; O'Hara, Niamh B.; Titus, Jonathan H.; Apple, Jennifer L.; Gill, Richard A.; Wynn, Louise

2010-01-01

Background The effect of low nutrient availability on plant-consumer interactions during early succession is poorly understood. The low productivity and complexity of primary successional communities are expected to limit diversity and abundance of arthropods, but few studies have examined arthropod responses to enhanced nutrient supply in this context. We investigated the effects of nitrogen (N) and phosphorus (P) addition on plant productivity and arthropod abundance on 24-yr-old soils at Mount St. Helens volcano. Methodology/Principal Findings We measured the relative abundance of eight arthropod orders and five families in plots that received N, P, or no nutrients for 3–5 years. We also measured plant % cover, leaf %N, and plant diversity. Vegetation responded rapidly to N addition but showed a lagged response to P that, combined with evidence of increased N fixation, suggested P-limitation to N availability. After 3 yrs of fertilization, orthopterans (primarily Anabrus simplex (Tettigoniidae) and Melanoplus spp (Acrididae)) showed a striking attraction to P addition plots, while no other taxa responded to fertilization. After 5 yrs of fertilization, orthopteran density in the same plots increased 80%–130% with P addition and 40% with N. Using structural equation modeling, we show that in year 3 orthopteran abundance was associated with a P-mediated increase in plant cover (or correlated increases in resource quality), whereas in year 5 orthopteran density was not related to cover, diversity or plant %N, but rather to unmeasured effects of P, such as its influence on other aspects of resource quality. Conclusions/Significance The marked surprising response to P by orthopterans, combined with a previous observation of P-limitation in lepidopteran herbivores at these sites, suggests that P-mediated effects of food quantity or quality are critical to insect herbivores in this N-P co-limited primary successional system. Our results also support a previous

Tratado Sobre os gigantes, de Fílon de Alexandria: apresentação, tradução, notas

Directory of Open Access Journals (Sweden)

César Motta Rios

2008-03-01

Full Text Available A importância da obra de Fílon de Alexandria ainda hoje é múltipla e real inclusive para o judaísmo. Conforme observado por David Runia (RUNIA, 1990, p. 185-186, seu estudo é válido para qualquer um que se interesse por literatura judaico-­helenística, judaísmo do segundo templo, Novo Testamento, patrística e gnosticismo, cultura helenística e filosofia grega.

Magnetic and geoelectrical surveying in the Roman age town Porolissum (NW Romania)

Science.gov (United States)

Petrovszki, J.

2009-04-01

We present the results of magnetic and geoelectrical surveys carried out in a Roman age town Porolissum (NW Romania). Porolissum was the capital of the province Dacia Porolissensis in the 2nd and 3rd centuries, and it had 20000 inhabitants. After the Romans left Dacia the town was deserted. The buildings in the town were built from dacite mined in nearby quarries. The dacite has large magnetic susceptibility and large electric resistivity compared to the soil, which allows the detection of the ruins by magnetic and geoelectrical measurements. We made magnetic surveying using GSM-19 Overhauser magnetometers in the fortress, the town and the cemetery. We were able to map streets, foundations of different buildings: houses, sanctuaries, and in the cemetery roads, graves and graveyards. In those places where the interpretation of the results of the magnetic surveys was not clear, geoelectrical measurements were made to clarify the presence of dacite. The geophysical surveys help to reconstruct the structure of the archeological objects, and on large scale the structure of the town. Based upon our results, the archeologists dug more trenches, which confirmed the interpretation of geophysical measurements.

Tectono-volcanic control of fissure type vents for the 28 Ma Panalillo ignimbrite in the Villa de Reyes Graben, San Luis PotosI, Mexico

International Nuclear Information System (INIS)

Tristan-Gonzalez, Margarito; Labarthe-Hernandez, Guillermo; Aguillon-Robles, Alfredo; Aguirre-DIaz, Gerardo J

2008-01-01

The volcano-tectonic events at the Villa de Reyes Graben (VRG), in the southern Sierra Madre Occidental, Mexico, include 1) a regional NNE fault system developed before 32 Ma, 2) this pre-32 Ma faulting controlled the emplacement of 31.5 Ma dacitic domes, 3) NE faulting at 28 Ma that displaced the 31.5 Ma dacitic domes and formed the VRG, as well as the oblique grabens of Bledos and Enramadas oriented NW, 4) emplacement of Panalillo ignimbrite at 28 Ma filling the VRG and erupting from fissures related to the oblique grabens, and eruption of Placa basalt apparently also from fault-controlled vents.

Tectono-volcanic control of fissure type vents for the 28 Ma Panalillo ignimbrite in the Villa de Reyes Graben, San Luis PotosI, Mexico

Energy Technology Data Exchange (ETDEWEB)

Tristan-Gonzalez, Margarito; Labarthe-Hernandez, Guillermo; Aguillon-Robles, Alfredo [Instituto de Geologia/DES IngenierIa, UASLP, Av. Dr. Manuel Nava 5, Zona Universitaria, C.P. 78240, San Luis PotosI, S.L.P. (Mexico); Aguirre-DIaz, Gerardo J [Centro de Geociencias, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro, 76230 (Mexico)], E-mail: mtiistan@uasln.mx, E-mail: ger@geociencias.unam.mx

2008-10-01

The volcano-tectonic events at the Villa de Reyes Graben (VRG), in the southern Sierra Madre Occidental, Mexico, include 1) a regional NNE fault system developed before 32 Ma, 2) this pre-32 Ma faulting controlled the emplacement of 31.5 Ma dacitic domes, 3) NE faulting at 28 Ma that displaced the 31.5 Ma dacitic domes and formed the VRG, as well as the oblique grabens of Bledos and Enramadas oriented NW, 4) emplacement of Panalillo ignimbrite at 28 Ma filling the VRG and erupting from fissures related to the oblique grabens, and eruption of Placa basalt apparently also from fault-controlled vents.

100th International Women’s Day Celebrated at CERN

CERN Multimedia

Katarina Anthony

2011-01-01

In celebration of the 100th year of International Women’s Day on 8 March, a special colloquium looking at high energy physics from a gender studies perspective was held at CERN.   Addressing a packed conference room, Helene Goetschel, a visiting gender studies researcher from Uppsala University, gave a presentation on a subject unfamiliar to most physicists: sociology. And more specifically, on the findings of gender researchers examining the field of high energy physics. “It was heartening to see so many CERN physicists interested in hearing how sociologists and historians see their community,” said Helene. “Examining our personal issues with gender is difficult, and I applaud anyone who takes an interest in the subject.” Helene Goetschel began her academic career in high-energy physics, but encountered a 'glass ceiling' in her work. In 1990, she decided to change the focus of her studies to the history of science – specifically looking ...

Hot pressing and lithification of gouge during the Mount St. Helens 2004-2008 eruption: insights from high temperature deformation experiments

Science.gov (United States)

Ryan, Amy G.; Russell, James K.; Heap, Michael J.

2017-04-01

We present results from an experimental program designed to investigate the timescales, conditions and mechanisms responsible for the densification and lithification of volcanic gouge at Mount St. Helens (MSH). From 2004-2008, MSH produced a series of lava domes/spines that were mantled by thick layers of gouge resulting from fracturing and cataclasis at the conduit-wall rock interface. The gouge comprises fine crystal-rich rock powder containing little to no glass. The erupted gouge carapace is texturally diverse, and varies from loose granular material to moderately indurated coherent rock to fine-grained cataclasite within tens of centimeters. The spatial association of these materials suggests that the originally unconsolidated conduit-fault gouge is densified and lithified during ascent to the surface. At present the conditions, timescales and mechanisms for lithification of the glass-poor materials are unknown. Here, we present results from a series of high-temperature (T) uniaxial deformation experiments performed on natural gouge collected from MSH (spine 5). The experiments are intended to (1) establish the feasibility of experimentally densifying/lithifying natural gouge materials at laboratory conditions approximating those within the MSH conduit, and to (2) constrain the effects of T, load and time on the extents, rates and mechanisms of densification. Our experimental conditions include T up to 800°C (Tmelting), axial differential stresses up to 25 MPa and experimental times up to 90 hours. Experimental results will be compared to the physical properties (density, porosity, permeability, compressive strength and particle size distribution) of variably densified gouge samples from spines 4, 5 and 7 at MSH, tying the results from the lab to the natural system. Initial results show an increase in the amount and rate of densification with increasing experimental T, with an increase in sample shortening (axial strain) between experiments completed at 650

Field-trip guide for exploring pyroclastic density current deposits from the May 18, 1980, eruption of Mount St. Helens, Washington

Science.gov (United States)

Brand, Brittany D.; Pollock, Nicholas; Sarocchi, Damiano; Dufek, Josef; Clynne, Michael A.

2017-07-05

Pyroclastic density currents (PDCs) are one of the most dangerous phenomena associated with explosive volcanism. To help constrain damage potential, a combination of field studies, laboratory experiments, and numerical modeling are used to establish conditions that influence PDC dynamics and depositional processes, including runout distance. The objective of this field trip is to explore field relations that may constrain PDCs at the time of emplacement.The PDC deposits from the May 18, 1980, eruption of Mount St. Helens are well exposed along the steep flanks (10–30° slopes) and across the pumice plain (5–12° slopes) as far as 8 km north of the volcano. The pumice plain deposits represent deposition from a series of concentrated PDCs and are primarily thick (3–12 m), massive, and poorly sorted. In contrast, the steep east-flank deposits are stratified to cross-stratified, suggesting deposition from PDCs where turbulence strongly influenced transport and depositional processes.The PDCs that descended the west flank were largely nondepositional; they maintained a higher flow energy and carrying capacity than PDCs funneled through the main breach, as evidenced by the higher concentration of large blocks in their deposits. The PDC from the west flank collided with PDCs funneled through the breach at various points along the pumice plain. Evidence for flow collision will be explored and debated throughout the field trip.Evidence for substrate erosion and entrainment is found (1) along the steep eastern flank of the volcano, which has a higher degree of rough, irregular topography relative to the west flanks where PDCs were likely nonerosive, (2) where PDCs encountered debris-avalanche hummocks across the pumice plain, and (3) where PDCs eroded and entrained material deposited by PDCs produced during earlier phases of the eruption. Two features interpreted as large-scale (tens of meters wide) levees and a large (~200 m wide) channel scour-and-fill feature

Remoção de Pb2+ e Cr3+ em solução por zeólitas naturais associadas a rochas eruptivas da formação serra geral, bacia sedimentar do Paraná Removal of Pb2+ and Cr3+ from aqueous solution by natural zeolites associated with eruptive rocks from the serra geral formation, Paraná sedimentary basin

Directory of Open Access Journals (Sweden)

Mirian Chieko Shinzato

2009-01-01

Full Text Available The capacity of natural zeolites and its host rock (dacite to remove Pb2+ and Cr3+ from aqueous solutions has been investigated. Results showed that both samples prefer to remove Pb2+ instead of Cr3+. Almost 100% of Pb2+ was removed from solutions with concentration until 50 mg L-1 and 100 mg L-1 of this metal, respectively by dacite and zeolite. The equilibrium of metals adsorption process was reached during the first 30 min by both materials. Na+ can be used to recover Pb2+, but not to remove Cr3+ from the treated samples. The Sips model showed a good fit for experimental data of this study.

Põlisrahvaste deklaratsioon / Helen Arusoo

Index Scriptorium Estoniae

Arusoo, Helen, 1972-

2010-01-01

Urmas Sisask kuulutas Tuhala Nõiakaevu kaitseks välja Tuhala ja Nabala karstialadel rahvusvahelise tähtsusega looduskaitsealaks toetudes internetis kogutud 60 000 toetusallkirjale ja 2007. aastal Eesti poolt allkirjastatud ÜRO põlisrahvaste õiguste deklaratsioonile web-static.vm.ee/static/failid/298/Polisrahvaste_deklaratsioon_EST.pdf

Betoonist videograafika / Helen Kivisoo

Index Scriptorium Estoniae

Kivisoo, Helen

2001-01-01

12. augustini Helsingis MUU galeriis Jasper Zoova videoinstallatsioon "Hebel - Betoonehitus uuest aspektist" ja Tuukka Kaila (Soome) fotod "Heissulivei - Vaadake kui ilus - Check out me and my country".

Elastic source model of the North Mono eruption (1325-1368 A.D.) based on shoreline deformation

Science.gov (United States)

Shaffer, Wil; Bursik, Marcus; Renshaw, Carl

2010-12-01

Topographic data from the Shuttle Radar Topography Mission (SRTM) captures the permanent deformation of a prominent highstand of Mono Lake, California USA. Deformation of the Dechambeau Ranch highstand shoreline was measured using the elevation of the beach berm—shoreline bluff break-in-slope. Point source models and a boundary element dike model were used to approximate the source of deformation underneath the northern end of the Mono Craters. The point source model could not adequately explain the observed deformation. The dike model yielded the best results for a NW trending dike dipping 60° NE and inflated to widths greater than 60 m. The results suggest that the geometry of the source is more complex than a simple vertical dike and that the deformation is better explained with a dipping dike following a normal fault, or an elongated cryptodome.

BridgeUP: STEM. Creating Opportunities for Women through Tiered Mentorship

Science.gov (United States)

Secunda, Amy; Cornelis, Juliette; Ferreira, Denelis; Gomez, Anay; Khan, Ariba; Li, Anna; Soo, Audrey; Mac Low, Mordecai

2018-01-01

BridgeUP: STEM is an ambitious, and exciting initiative responding to the extensive gender and opportunity gaps that exist in the STEM pipeline for women, girls, and under-resourced youth. BridgeUP: STEM has developed a distinct identity in the landscape of computer science education by embedding programming in the context of scientific research. One of the ways in which this is accomplished is through a tiered mentorship program. Five Helen Fellows are chosen from a pool of female, postbaccalaureate applicants to be mentored by researchers at the American Museum of Natural History in a computational research project. The Helen Fellows then act as mentors to six high school women (Brown Scholars), guiding them through a computational project aligned with their own research. This year, three of the Helen Fellows, and by extension, eighteen Brown Scholars, are performing computational astrophysics research. This poster presents one example of a tiered mentorship working on modeling the migration of stellar mass black holes (BH) in active galactic nucleus (AGN) disks. Making an analogy from the well-studied migration and formation of planets in protoplanetary disks to the newer field of migration and formation of binary BH in AGN disks, the Helen Fellow is working with her mentors to make the necessary adaptations of an N-body code incorporating migration torques from the protoplanetary disk case to the AGN disk case to model how binary BH form. This is in order to better understand and make predictions for gravitational wave observations from the Laser Interferometer Gravitational-Wave Observatory (LIGO). The Brown Scholars then implement the Helen Fellow’s code for a variety of different distributions of initial stellar mass BH populations that they generate using python, and produce visualizations of the output to be used in a published paper. Over the course of the project, students will develop a basic understanding of the physics related to their project and

Les grandes étapes d'évolution d'un volcan andésitique composite: Exemple du Nevado de Toluca (Méxique)

Science.gov (United States)

Cantagrel, J. M.; Robin, C.; Vincent, P.

1981-06-01

The Nevado de Toluca, in the middle of the Mexican volcanic belt, has been built by two very dissimilar phases. The first one that lasted more than one million years is mainly andesitic. Numerous massive and autobrecciated lava flows of this phase pass outwards into thick conglomeratic formations. The volume of this primitive volcano represents the essential part of the Nevado. After an intense periode of erosion, the second phase is of very short duration (about 100.000 years) and is dacitic in nature. Three main episode can be distinguished: 1. Eruption of important ash and pumice pyroclastic flows related to caldera collapse above a shallow magmatic reservoir. 2. Extrusions of several dacitic domes within and outside the caldera with numerous associated «nuées ardentes» surrounding the volcano. 3. Plinian eruption leading to widespread pumiceous air-fall and to the opening of the present crater inside the caldera. Extrusion of a new small dacitic dome and late phreatic explosions. This second sequence of events can be interpreted as the progressive emptying of the crustal magmatic chamber without refilling by a new magma supply. The most recent activity in the area is represented by monogenic cones and flows of basic andesites outside the central vent system of the Nevado.

Preliminary chronostratigraphy of the Tetagouche and Fournier groups in northern New Brunswick

International Nuclear Information System (INIS)

Sullivan, R.W.; VanStaal, C.R.

1996-01-01

Seven U-Pb zircon ages of volcanic rocks from northern New Brunswick are reported and a preliminary stratigraphy of the middle Ordovician Tetagouche and Fournier groups is presented. Deposition of the Tetagouche Group started with calcareous rocks of the Vallee Lourdes Formation in the Late Arenig (>470 Ma). Quartz- and feldspar-phyric felsic volcanic rocks of the immediately overlying Nepisiquit Falls Formation yielded U-Pb zircon ages between ca. 471 and 469 Ma. These volcanic rocks are time stratigraphic equivalents of the feldspar-phyric dacites of the Spruce Lake Formation, which yielded a U-Pb zircon age of ca. 470 Ma, and tholeiitic and alkalic pillow basalts of the structurally overlying Canoe Landing Lake Formation. The final phase of rhyolitic to dacitic volcanism is marked by the emplacement of distinct quartz- and feldspar-phyric dacitic porphyries at ca. 465 Ma, thus limiting silicic volcanism to the Late Arenig and llanvim. During the Ilandeilo and Caradoc (ca. 464-457 Ma) volcanic activity in the Tetagouche Group was characterized by extrusion of alkali basalts and minor comendites, interlayered with dark shales and siltstones of the Boucher Brook Formation. Oceanic crust of the Fournier Group was also formed during this period. (author). 29 refs., 1 tab., 10 figs

Preliminary chronostratigraphy of the Tetagouche and Fournier groups in northern New Brunswick

Energy Technology Data Exchange (ETDEWEB)

Sullivan, R W; VanStaal, C R [Geological Survey of Canada, Ottawa, ON (Canada)

1997-12-31

Seven U-Pb zircon ages of volcanic rocks from northern New Brunswick are reported and a preliminary stratigraphy of the middle Ordovician Tetagouche and Fournier groups is presented. Deposition of the Tetagouche Group started with calcareous rocks of the Vallee Lourdes Formation in the Late Arenig (>470 Ma). Quartz- and feldspar-phyric felsic volcanic rocks of the immediately overlying Nepisiquit Falls Formation yielded U-Pb zircon ages between ca. 471 and 469 Ma. These volcanic rocks are time stratigraphic equivalents of the feldspar-phyric dacites of the Spruce Lake Formation, which yielded a U-Pb zircon age of ca. 470 Ma, and tholeiitic and alkalic pillow basalts of the structurally overlying Canoe Landing Lake Formation. The final phase of rhyolitic to dacitic volcanism is marked by the emplacement of distinct quartz- and feldspar-phyric dacitic porphyries at ca. 465 Ma, thus limiting silicic volcanism to the Late Arenig and llanvim. During the Ilandeilo and Caradoc (ca. 464-457 Ma) volcanic activity in the Tetagouche Group was characterized by extrusion of alkali basalts and minor comendites, interlayered with dark shales and siltstones of the Boucher Brook Formation. Oceanic crust of the Fournier Group was also formed during this period. (author). 29 refs., 1 tab., 10 figs.

Using program impact pathways to understand and improve program delivery, utilization, and potential for impact of Helen Keller International's homestead food production program in Cambodia.

Science.gov (United States)

Olney, Deanna K; Vicheka, Sao; Kro, Meng; Chakriya, Chhom; Kroeun, Hou; Hoing, Ly Sok; Talukder, Aminzzaman; Quinn, Victoria; Iannotti, Lora; Becker, Elisabeth; Roopnaraine, Terry

2013-06-01

Evidence of the impact of homestead food production programs on nutrition outcomes such as anemia and growth is scant. In the absence of information on program impact pathways, it is difficult to understand why these programs, which have been successful in increasing intake of micronutrient-rich foods, have had such limited documented impact on nutrition outcomes. To conduct a process evaluation of Helen Keller International's (HKI's) homestead food production program in Cambodia to assess whether the program was operating as planned (in terms of design, delivery, and utilization) and to identify ways in which the program might need to be strengthened in order to increase its potential for impact. A program theory framework, which laid out the primary components along the hypothesized program impact pathways, was developed in collaboration with HKI and used to design the research. Semistructured interviews and focus group discussions with program beneficiaries (n = 36 and 12, respectively), nonbeneficiaries (n = 12), and program implementers (n = 17 and 2, respectively) and observations of key program delivery points, including health and nutrition training sessions (n = 6), village model farms (n = 6), and household gardens of beneficiaries (n = 36) and nonbeneficiaries (n = 12), were conducted to assess the delivery and utilization of the primary program components along the impact pathways. The majority of program components were being delivered and utilized as planned. However, challenges with some of the key components posited to improve outcomes such as anemia and growth were noted. Among these were a gap in the expected pathway from poultry production to increased intake of eggs and poultry meat, and some weaknesses in the delivery of the health and nutrition training sessions and related improvements in knowledge among the village health volunteers and beneficiaries. Although the program has been successful in delivering the majority of the program

Komatiites and nickel sulphide orebodies of the Black Swan area, Yilgarn Craton, Western Australia. 1. Petrology and volcanology of host rocks

Science.gov (United States)

Hill, R. E. T.; Barnes, S. J.; Dowling, S. E.; Thordarson, T.

2004-11-01

The Black Swan Succession is a bimodal association of dacitic and komatiitic volcanic rocks located about 50 km NNE of Kalgoorlie, within the 2.7-Ga Eastern Goldfields greenstone province of the Yilgarn Craton. The komatiite stratigraphy comprises a steep dipping, east facing package about 700 m in maximum thickness and about 2.5 km in strike length (Fig. 1), which hosts a number of economically exploitable Ni sulphide orebodies including the Silver Swan massive ore shoot (approximately half a million tonnes at about 10.5% Ni). The sequence can be subdivided into a Lower Felsic Unit, comprising coherent and autobrecciated facies of multiple dacite lava flows; an upper Eastern and lower Western Ultramafic Unit, each showing marked lateral facies variation, and an Upper Felsic Unit coeval with the Eastern Ultramafic Unit. The komatiite sequence has been metamorphosed at sub-greenschist facies in the presence of high proportions of CO2-rich fluid, giving rise to pervasive talc carbonate and talc carbonate quartz assemblages, with extensive preservation of pseudomorphed igneous textures. Cores of lizardite serpentinite are present in the thickest parts of the ultramafic succession. The degree of penetrative deformation is generally very low, and original stratigraphic relationships are largely intact in much of the sequence. The Eastern Ultramafic Unit and Western Ultramafic Unit are interpreted as components of a single large komatiite flow field, representing overlapping stages in the emplacement of a series of distributory lava pathways and flanking sheet flows. The Western Ultramafic Unit which hosts the bulk of the high-grade massive and disseminated ores is a sequence dominated by coarse-grained olivine cumulates, 2 km wide and up to 500 m thick, with major magma pathways represented by thick, homogenous olivine mesocumulate piles at its northern and southern ends: respectively 400 and 200 m thick. The sequence between the two major pathways consists of olivine

Petrogenetic evolution of the felsic and mafic volcanic suite in the Siang window of Eastern Himalaya, Northeast India

Directory of Open Access Journals (Sweden)

A. Krishnakanta Singh

2012-09-01

Full Text Available The Abor volcanics outcroping in the core of the Siang window in the Eastern Himalaya comprise voluminous mafic volcanics (47%–56% w(SiO2, with subordinate felsic volcanics (67%–75% w(SiO2. The felsic volcanics are dacitic to rhyolitic in composition and are typically enriched in LREE (La/SmN = 3.09–3.90 with high REE contents (256–588 ppm, moderately fractionated REE patterns (CeN/YbN = 6.54–9.52 and pronounced negative Eu anomalies (Eu/Eu* = 0.55–0.72. Wide variations in Rb/Zr, K/Rb and La/Sm ratios suggest that they were derived from magmas which were randomly contaminated with crustal material. Chemical characteristics and petrogenetic modelling indicate that the dacites were generated by ∼15% partial melting of a mafic source leaving a residue with 55% plagioclase, 14% orthoclase, 18% clinopyroxene, 5% orthopyroxene, 8% hornblende. The silica-rich rhyodacites and rhyolites were derived from a dacite magma source by a higher degree (>45% fractional crystallization of an assemblage consisting of 70% plagioclase, 12% clinopyroxene, 7% amphibole and 11% magnetite. The associated LREE-LILE enrichment and pronounced negative anomalies for HFSE (Nb, P, and Ti exhibited by these felsic volcanics are characteristic of continental rift volcanism, implying that they were emplaced during lithospheric extension.

Modeling Surface Processes Occurring on Moons of the Outer Solar System

Science.gov (United States)

Umurhan, O. M.; White, O. L.; Moore, J. M.; Howard, A. D.; Schenk, P.

2016-12-01

A variety of processes, some with familiar terrestrial analogs, are known to take place on moon surfaces in the outer solar system. In this talk, we discuss the observed features of mass wasting and surface transport seen on both Jupiter's moon Calisto and one of Saturn's Trojan moons Helene. We provide a number of numerical models using upgraded version of MARSSIM in support of several hypotheses suggested on behalf of the observations made regarding these objects. Calisto exhibits rolling plains of low albedo materials surrounding relatively high jutting peaks harboring high albedo deposits. Our modeling supports the interpretation that Calisto's surface is a record of erosion driven by the sublimation of CO2 and H2O contained in the bedrock. Both solar insolation and surface re-radiation drives the sublimation leaving behind debris which we interpret to be the observed darkened regolith and, further, the high albedo peaks are water ice deposits on surface cold traps. On the other hand, the 45 km scale Helene, being a milligravity environment, exhibits mysterious looking streaks and grooves of very high albedo materials extending for several kilometers with a down-sloping grade of 7o-9o. Helene's cratered terrain also shows evidence of narrowed septa. The observed surface features suggest some type of advective processes are at play in this system. Our modeling lends support to the suggestion that Helene's surface materials behave as a Bingham plastic material - our flow modeling with such rheologies can reproduce the observed pattern of streakiness depending upon the smoothness of the underlying bedrock; the overall gradients observed; and the narrowed septa of inter-crater regions.

Structure Of Conduits Of The Acidic Volcanism And Related Deposits In The Paraná-Etendeka Magmatic Province, São Marcos Region, South Brazil

Science.gov (United States)

Guimarães, L. F.; De Campos, C. P.; Lima, E. F. D.; Janasi, V. A.

2015-12-01

Voluminous acidic volcanics from the Paraná-Etendeka Magmatic Province crop out in the southern part of Brazil. The conduits responsible for the feeding of this intermediate/acid volcanism are preserved and well exposed in the São Marcos region (Lima et al. 2012; Geologia USP 12:49-64). Conduits are aligned along a NW-SE trend and have thicknesses up to 1 km. These structures are often characterized by mixing between dacitic and rhyodacitic magmas, with intercalation between two major zones: 1) reddish or grayish vitrophiricdacite/rhyodacite, sub-divided in massive or vesiculated; 2) reddish or grayish vitrophiric fragmented dacite/rhyodacite composed of bubble-rich angular to rounded blocks. Such fragments commonly deform coeval to the flow. A third zone dominated by filaments depicts a chaotic stretching-and-folding process from the mixture of the acid magmas. We used classical field measurements of flow structures and recognized main flow directions in these feeder-dikes. They follow two preferential directions: NW, ranging from N272° to N 355°, and NE, varying from N20° to N85°. These directions are indicative of a transtensive fissural system, which seems to be related to conjugated fractures. Evidence of an important fragmentation process in the conduits point towards the presence of related products in this region, thus rheomorphic deposits such as those observed elsewhere (e.g. Uruguay and Namibia) are expected to occur. Possible vestiges of these deposits could be represented by restricted outcrops of lens-shaped and banded hipohyaline, occasionally bubble-rich, dacites. The presence of continuous pseudotachylitic levels, tightly folded bands with horizontal axial planes together with local deformed bubble-rich pumice-like lens could be indicative of remelting and rheomorphism of previous vulcanoclastic material. Coulees and compound (lobed) dacitic lava flows, reaching up to 5-8 meters length, occur as the uppermost deposits and correspond to the

Mineralogy and REE geochemistry at Gomish-Tappeh Zn-Pb-Cu (Ag deposit, southwest of Zanjan

Directory of Open Access Journals (Sweden)

Tooba Salehi

2010-11-01

Full Text Available Gomish-Tappeh Zn-Pb-Cu (Ag deposit is located 90 km southwest of Zanjan, in northwestern part of Urumieh-Dokhtar volcano-plutonic zone. Exposed rocks at the area include Oligo-Miocene volcano-sedimentary and sedimentary sequences as well as Pliocene volcano-plutonic sequence (andesite porphyry dykes, dacitic subvolcanic dome and rhyodacitic volcanics. Alteration in the deposit developed as silicic, silicic-sulfidic, sericitic, carbonate, argillic and propylitic. Main mineralization at the Gomish-Tappeh deposit is observed as veins occurring in a steeply-deeping normal fault defined by an NE-SW trend in host rocks such as dacitic crystal litic tuff, dacitic subvolcanic dome, specifically the rhyolitic tuff. Paragenetic minerals in the ore veins consist of pyrite, arsenopyrite, chalcopyrite, bornite, low-Fe sphalerite, galena, tetrahedrite and specularite. Gangue minerals accompanying the ores include quartz, calcite, chlorite, sericite and clay minerals. Based on geochemical data, average grades for samples from the ore veins at the Gomish-Tappeh deposit are: 4% Pb, 6% Zn, 2% Cu and 88 ppm Ag. Moreover, REE distribution patterns for altered samples of the dacitic subvolcanic dome and acidic tuff when compared with fresh samples, show enrichment in LREE, while HREE demonstrate various bahaviours. The negative Eu anomaly in chondrite-normalized REE patterns for these rocks is related to the increase in fluid/rock ratio and destruction of those grains of plagioclase enriched in Eu. REE distribution patterns for the silty tuff (footwall to the ore compared with acidic tuff represent enrichment in all REE as well as positive Eu anomalies. However, the ore samples indicate more enrichment in LREE/HREE ratios and higher Eu contents when compared with wallrock of the ore veins (silty tuff. This is due to the influence of chloric magmatic-hydrothermal fluids that caused alteration along the ore zone, releasing LREE and Eu from the host rocks and finally

Localized rejuvenation of a crystal mush recorded in zircon temporal and compositional variation at the Lassen Volcanic Center, northern California.

Directory of Open Access Journals (Sweden)

Erik W Klemetti

Full Text Available Zircon ages and trace element compositions from recent silicic eruptions in the Lassen Volcanic Center (LVC allow for an evaluation of the timing and conditions of rejuvenation (reheating and mobilization of crystals within the LVC magmatic system. The LVC is the southernmost active Cascade volcano and, prior to the 1980 eruption of Mount St. Helens, was the site of the only eruption in the Cascade arc during the last century. The three most recent silicic eruptions from the LVC were very small to moderate-sized lava flows and domes of dacite (1915 and 27 ka eruptions of Lassen Peak and rhyodacite (1.1 ka eruption of Chaos Crags. These eruptions produced mixed and mingled lavas that contain a diverse crystal cargo, including zircon. 238U-230Th model ages from interior and surface analyses of zircon reveal ages from ∼17 ka to secular equilibrium (>350 ka, with most zircon crystallizing during a period between ∼60-200 ka. These data support a model for localized rejuvenation of crystal mush beneath the LVC. This crystal mush evidently is the remnant of magmatism that ended ∼190 ka. Most zircon are thought to have been captured from "cold storage" in the crystal mush (670-725°C, Hf >10,000 ppm, Eu/Eu* 0.25-0.4 locally remobilized by intrusion of mafic magma. A smaller population of zircon (>730°C, Hf 0.4 grew in, and are captured from, rejuvenation zones. These data suggest the dominant method to produce eruptible melt within the LVC is small-scale, local rejuvenation of the crystal mush accompanied by magma mixing and mingling. Based on zircon stability, the time required to heat, erupt and then cool to background conditions is relatively short, lasting a maximum of 10 s-1000 s years. Rejuvenation events in the LVC are ephemeral and permit eruption within an otherwise waning and cooling magmatic body.

5S-menetelmän implementointi

OpenAIRE

Kaikula, Kari-Marko

2017-01-01

Tässä opinnäytetyössä tavoiteltiin siisteyden ja järjestyksen tuomista 5S-menetelmän avulla Helen Oy:n kunnossapidon varaosavarastoon Salmisaaren voimalaitoksella. Helen Oy on Helsingin kaupungin omistama energia-alan yritys. Kehittämistehtävänä työssä oli 5S-menetelmän implementointi. Tutkimuksen tarkoituksena oli tutkia niitä seikkoja, jotka vaikuttavat 5S-menetelmän käyttöönottoon. 5S on menetelmä, jolla tuodaan siisteyttä ja järjestystä työympäristöön. Tutkimusmenetelmänä oli toiminta...

Rb-Sr and Ar-Ar systematics of Malani volcanic rocks of southwest Rajasthan: evidence for a younger post-crystallization thermal event

International Nuclear Information System (INIS)

Rathore, S.S.; Srivastava, R.K.

1996-01-01

A new Rb-Sr age of 779 ± 10 Ma has been obtained for a suite of andesite-dacite-rhyolite from the Malani igneous province of southwestern Rajasthan, dated earlier at 745 ± 10 Ma by Crawford and Compston (1970). The associated basalts may be slightly younger than the felsic volcanics and have a mantle source. The felsic volcanics on the other hand were most probably derived by fractional crystallization of a crustal magma. 40 Ar- 39 Ar systematics of three samples viz., a basalt, a dacite and a rhyolite show disturbed age spectra indicating a thermal event around 500-550 Ma ago. This secondary thermal event is quite wide-spread and possibly related to the Pan-African thermo-tectonic episode observed in the Himalayas and south India. (author). 38 refs., 5 figs., 2 tabs

Olelusvõitlus bioloogiarindel / Helen Urbanik

Index Scriptorium Estoniae

Urbanik, Helen

2002-01-01

Ameerika koolides tahetakse lastele darvinismi asemel õpetada teooriat, mis ei püüagi elu tekkimist Maal selgitada. Mõtteviisist, mida nimetatakse mõistuspärase loomise teooriaks (intelligent design theory ehk lühidalt ID teooria)

Multielemental analyses of tree rings by inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Hall, G.S.

1990-01-01

Inductively coupled plasma mass spectrometry (ICP-MS) was evaluated for major, minor, trace, and ultra-trace elemental analyses of individual tree rings. The samples were obtained from an old-growth Douglas fir growing near Mount St. Helens volcano, and from trees at various other North American sites. Eightly percent of elements from Li to U had detection limits in the solid (wood) below 8.0 ng g -1 . Two anomalous peaks occur in Mount St. Helens samples at A.D. 1478 and 1490 that closely correlate with past eruptions of the volcano. These results show that ICP-MS is a rapid and sensitive analytical method for multielemental analyses of individual tree rings. (author) 16 refs.; 2 figs.; 2 tabs

Petrographic analysis of samples

African Journals Online (AJOL)

etemu

contents fall in the field of trachy-dacite, and those from the Kiejo volcano fall in the field of basaltic trachy-andesite .... Arrow indicates breach in Southern caldera wall. (b) Schematic structural ..... Geowissenschaften: FU Berlin: McBirney 1993 ...

Pärleid vanapaberi hulgast : kohtumisi inimeste ja vanaraamatuga / Uno Schultz

Index Scriptorium Estoniae

Schultz, Uno, 1956-

2010-01-01

Bibliofiil Uno Schultzi vanaraamatute kogu kujunemisest ning inimestest, kellega haruldaste raamatute leidmisel kohtutud, sh Kyra Robertist, Voldemar Millerist, Trivimi Vellistest, Oskar Kuningast, Helene Kulpast, Erik Tederist jt.

Ruumieksperiment nimega Arhitektuurikatel = A spatial experiment called Arhitektuurikatel (Architecture Hub) / Artur Ümar, Tõnu Laigu

Index Scriptorium Estoniae

Ümar, Artur

2014-01-01

Arhitektuurikatel Tallinnas Põhja puiesteel. Arhitektuur: Tõnu Laigu, Koit Ojaliiv (QP Arhitektid), võistlusel osalesid ka Helen Rebane ja Triinu Silla. Sisearhitektuur: Andres Labi, Janno Roos (Ruumilabor). Valmimisaasta: 2013

Mati Undi teater revisited / Luule Epner

Index Scriptorium Estoniae

Epner, Luule, 1953-

2009-01-01

Teatrilavastuste taastamisest üldisemalt. Pikemalt festivali UNT! programmis etendunud Mati Undi lavastustest "Majahoidja", "Vaimude tund Jannseni tänaval", "Helene, Marion ja Felix", originaali ja taastatud variandi võrdlus

Krokodill sõi karu mett / Eero Kangor

Index Scriptorium Estoniae

Kangor, Eero, 1982-

2007-01-01

Tartu Ülikooli, Tartu Kõrgema Kunstikooli ja Tartu Kunstikooli õpilaste näitusest Tartu Kunstimuuseumis, kuraator Liisa Kaljula. Pikemalt Ronald Baumanni, Helen Kikkase, Margit Lõhmuse maalidest, Jana Huuli skulptuurist

Naisfotograafid, kes avavad meie silmad / Katie Breen

Index Scriptorium Estoniae

Breen, Katie

2008-01-01

Fotograafid Ami Vitale, Helene David, Stephanie Sinclair, Lauren Greenfield, Deirdre Brennan, Veronique de Viguerie, Christine Spengler pildistavad võõraid kultuure Aafrikas, Alaskal, Afganistanis, Iraagis. 9 fotot. Portreefotod fotograafidest

Elizabeth II üle Diana ja Tony / Kristiina Davidjants

Index Scriptorium Estoniae

Davidjants, Kristiina, 1974-

2007-01-01

Stephen Frearsi mängufilm "Kuninganna" ("The Queen") : stsenarist Peter Morgan : kuninganna Elizabeth II kehastab Helen Mirren peaminister Tony Blair'i Michael Sheen: Suurbritannia - Ameerika Ühendriigid - Itaalia 2006

Tectonic and volcanic implications of a cratered seamount off Nicobar Island, Andaman Sea

Digital Repository Service at National Institute of Oceanography (India)

KameshRaju, K.A.; Ray, D.; Mudholkar, A.V.; Murty, G.P.S.; Gahalaut, V.K.; Samudrala, K.; Paropkari, A.L.; Ramachandran, R.; SuryaPrakash, L.

seamount with well-developed crater at the summit was discovered near to the center of the Nicobar swarm. Rock samples collected by TV-guided grab from the seamount crater are dacite, rhyolite and andesite type with a veneer of ferromanganese oxide coating...

Interrelations among pyroclastic surge, pyroclastic flow, and lahars in Smith Creek valley during first minutes of 18 May 1980 eruption of Mount St. Helens, USA

Science.gov (United States)

Brantley, S.R.; Waitt, R.B.

1988-01-01

A devastating pyroclastic surge and resultant lahars at Mount St. Helens on 18 May 1980 produced several catastrophic flowages into tributaries on the northeast volcano flank. The tributaries channeled the flows to Smith Creek valley, which lies within the area devastated by the surge but was unaffected by the great debris avalanche on the north flank. Stratigraphy shows that the pyroclastic surge preceded the lahars; there is no notable "wet" character to the surge deposits. Therefore the lahars must have originated as snowmelt, not as ejected water-saturated debris that segregated from the pyroclastic surge as has been inferred for other flanks of the volcano. In stratigraphic order the Smith Creek valley-floor materials comprise (1) a complex valley-bottom facies of the pyroclastic surge and a related pyroclastic flow, (2) an unusual hummocky diamict caused by complex mixing of lahars with the dry pyroclastic debris, and (3) deposits of secondary pyroclastic flows. These units are capped by silt containing accretionary lapilli, which began falling from a rapidly expanding mushroom-shaped cloud 20 minutes after the eruption's onset. The Smith Creek valley-bottom pyroclastic facies consists of (a) a weakly graded basal bed of fines-poor granular sand, the deposit of a low-concentration lithic pyroclastic surge, and (b) a bed of very poorly sorted pebble to cobble gravel inversely graded near its base, the deposit of a high-concentration lithic pyroclastic flow. The surge apparently segregated while crossing the steep headwater tributaries of Smith Creek; large fragments that settled from the turbulent surge formed a dense pyroclastic flow along the valley floor that lagged behind the front of the overland surge. The unusual hummocky diamict as thick as 15 m contains large lithic clasts supported by a tough, brown muddy sand matrix like that of lahar deposits upvalley. This unit contains irregular friable lenses and pods meters in diameter, blocks incorporated from

21. X avati Kaunase kunstibiennaal "Textile 2005"

Index Scriptorium Estoniae

2005-01-01

Eestist osalevad Mare Kelpmann, Marika Kööbi, Aet Ollisaar, Kadi Pajupuu, Ludmilla Svarzhevska, Hanna Tiidus, Helen Kauksi, Krista Leesi, Aune Taamal, Erika Tammpere, Milvi Thalheim ja Erle Võsa-Tangsoo

Applying Strategic Management in the Office of the Assistant Secretary of the Army for Financial Management and Comptroller (ASA(FM&C))

National Research Council Canada - National Science Library

Sturek, Frank

2000-01-01

The Assistant Secretary of the Army for Financial Management and Comptroller (ASA(FM&C)), the Honorable Mrs. Helen T. McCoy, started an organizational performance improvement initiative in September 1999...

The evolution of hydrous magmas in the Tongariro Volcanic Centre : the 10 ka Pahoka-Mangamate eruptions

International Nuclear Information System (INIS)

Auer, A.; Palin, J.M.; White, J.D.L.; Nakagawa, M.; Stirling, C.

2015-01-01

The majority of arc-type andesites in the Tongariro Volcanic Centre are highly porphyritic, hornblende-free, two-pyroxene andesites. An exception is tephras from the c. 10,000 ka Pahoka-Mangamate event. Magmas of these Plinian eruptions bypassed the extensive crustal mush columns under the central volcanoes and sequentially derived a series of almost aphyric rocks spanning a compositional range from dacite to basaltic andesite. Mineral composition, trace element and isotopic data suggest that this eruptive series tapped a mid-crustal magma reservoir, resulting in the initial eruption of an hydrous dacitic magma and several following eruptions characterised by less-evolved and less-hydrous compositions at progressively higher temperatures and substantially lower 87 Sr/ 86 Sr ratios. Systematic changes in magma chemistry are also reflected in a sequential change in phenocryst content starting with an early hornblende-plagioclase-dominated assemblage to a late olivine-plagioclase-dominated assemblage. (author).

The Mount Edgecumbe tephra deposits, a marker horizon in southeastern Alaska near the Pleistocene-Holocene boundary

Science.gov (United States)

Riehle, J.R.; Mann, D.H.; Peteet, D.M.; Engstrom, D.R.; Brew, D.A.; Meyer, C.E.

1992-01-01

Late Pleistocene tephra deposits found from Sitka to Juneau and Lituya Bay are assigned to a source at the Mount Edgecumbe volcanic field, based on similarity of glass compositions to nearvent deposits and on thinning away from Kruzof Island. The sequence of near-vent layers is basaltic andesite and andesite at the base, rhyolite, and mixed dacite and rhyolite on top. The only breaks in the tephra sequence are two 1-mm-thick silt partings in a lake-sediment core, indicating a depositional interval from basaltic andesite to dacite of no more than about a millennium. Tephra deposits at sites >30 km from the vent are solely dacite and rhyolite and are 10,600 to 11,400 14C yr old based on interpretation of 18 radiocarbon ages, including 5 by accelerator mass spectrometry (AMS). Basaltic andesite and andesite deposits nearer the vent are as much as 12,000 yr old. Discrepancy among radiocarbon ages of upland tephra deposits provisionally correlated as the same grainfall is resolvable within ??2 ?? of analytical uncertainty. Comparison of bulk and AMS ages in one sediment core indicates a systematic bias of +600 to +1100 yr for the bulk ages; correlation of tephra deposits among upland and lacustrine sites implies an additional discrepancy of 200-400 yr between upland (relatively too young) and lacustrine ages. In any case, the Mount Edgecumbe tephra deposits are a widespread, latest Pleistocene stratigraphic marker that serves to emphasize the uncertainty in dating biogenic material from southeastern Alaska. ?? 1992.

Belgia printsessi tervitatakse "Everybody" viisile tehtud lauluga

Index Scriptorium Estoniae

2001-01-01

Belgia kroonprintsessi Mathilde tõi eelmisel nädalal ilmale tütre, kelle nimeks on Elisabeth Therese Marie Helene. Belgia pensionärid tervitasid kroonprintsessi eesti eurolaulu viisile tehtud lauluga

Rahvuslikus stiilis lastetuba meeldis nii asjatundjatele kui ka publikule / Siret Mägi

Index Scriptorium Estoniae

Mägi, Siret

2007-01-01

Tallinna Mustika ostukeskuses kuulutati välja sisekujunduskonkursi "Rahvuslik tuba" võitjad. Parimaks tunnistati Eva Herrera, II koha pälvis Gudrun Vung ning III koha Helen Sarapuu ja Katrin Rooger

"Gerontiuse unenägu" Estonias / Igor Garšnek

Index Scriptorium Estoniae

Garšnek, Igor, 1958-

2010-01-01

2. aprillil Estonia kontserdisaalis toimunud Edward Elgari oratooriumi "Gerontiuse unenägu" ettekandest, esitasid: ERSO, Estonia ooperikoor, Estonia poistekoor, kammerkoor Voces Musicales, Helen Lokuta, Bernhard Gärtner, Priit Volmer, dirigent Carlos Spiereri

Resenha: Power, Interdependence and Nonstate Actors in World Politics

Directory of Open Access Journals (Sweden)

Katiuscia Moreno Galhera Espósito

2011-10-01

Full Text Available Resenha do livro: Moravcsik, Andrew; Milner, Helen V. (org.. Power, Interdependence and Nonstate Actors in World Politics. New Jersey: Princeton University Press, 2009. ISBN 978-0-691-14027-8

Нарвский киноэкран станет окном в Лондонский театр

Index Scriptorium Estoniae

2009-01-01

25. juunil stardib Forum Cinemas keti kinodes pilootprojekt, kus linale jõuab otseülekanne Londoni Rahvusteatri etendusest "Phaidra", lavastaja Nicholas Hytner, peaosas Helen Mirren. Projektis osaleb ka Narva kino Forum Cinemas Astri

Soome kirikudisain, Schjerfbecki autoportreed, Mucha juugend / Harry Liivrand

Index Scriptorium Estoniae

Liivrand, Harry, 1961-

2006-01-01

Näitus "Tuvi ja tall - Helsingi kirikute sakraalne disain" Helsingi disainimuuseumis. Helene Schjerfbecki (1862-1946) näitus Didrichseni kunstimuuseumis. Alphonse Mucha (1860-1939) ehete ja teatriplakatite näitus Amos Andersoni Taidemuseumis

Volcanoes: Coming Up from Under.

Science.gov (United States)

Science and Children, 1980

1980-01-01

Provides specific information about the eruption of Mt. St. Helens in March 1980. Also discusses how volcanoes are formed and how they are monitored. Words associated with volcanoes are listed and defined. (CS)

High-resolution digital elevation model of lower Cowlitz and Toutle Rivers, adjacent to Mount St. Helens, Washington, based on an airborne lidar survey of October 2007

Science.gov (United States)

Mosbrucker, Adam

2015-01-01

The lateral blast, debris avalanche, and lahars of the May 18th, 1980, eruption of Mount St. Helens, Washington, dramatically altered the surrounding landscape. Lava domes were extruded during the subsequent eruptive periods of 1980–1986 and 2004–2008. More than three decades after the emplacement of the 1980 debris avalanche, high sediment production persists in the Toutle River basin, which drains the northern and western flanks of the volcano. Because this sediment increases the risk of flooding to downstream communities on the Toutle and lower Cowlitz Rivers, the U.S. Army Corps of Engineers (USACE), under the direction of Congress to maintain an authorized level of flood protection, continues to monitor and mitigate excess sediment in North and South Fork Toutle River basins to help reduce this risk and to prevent sediment from clogging the shipping channel of the Columbia River. From October 22–27, 2007, Watershed Sciences, Inc., under contract to USACE, collected high-precision airborne lidar (light detection and ranging) data that cover 273 square kilometers (105 square miles) of lower Cowlitz and Toutle River tributaries from the Columbia River at Kelso, Washington, to upper North Fork Toutle River (below the volcano's edifice), including lower South Fork Toutle River. These data provide a digital dataset of the ground surface, including beneath forest cover. Such remotely sensed data can be used to develop sediment budgets and models of sediment erosion, transport, and deposition. The U.S. Geological Survey (USGS) used these lidar data to develop digital elevation models (DEMs) of the study area. DEMs are fundamental to monitoring natural hazards and studying volcanic landforms, fluvial and glacial geomorphology, and surface geology. Watershed Sciences, Inc., provided files in the LASer (LAS) format containing laser returns that had been filtered, classified, and georeferenced. The USGS produced a hydro-flattened DEM from ground-classified points at

Insights into magmatic evolution and recharge history in Capraia Volcano (Italy) from chemical and isotopic zoning in plagioclase phenocrysts

DEFF Research Database (Denmark)

Gagnevin, D.; Waight, Tod Earle; Daly, J.S.

2007-01-01

Plagioclase phenocrysts in dacites from the high-K calc-alkaline CapraiaVolcano were investigated for major, trace element and Sr isotope variations in order to gain better insight into the proposed open-system behaviour of the volcano. Repeated dissolution zone in plagioclases from the early-eru...

Bereaved Employee: Returning to Work

Science.gov (United States)

... Work Working Through Grief About Us The Bereaved Employee: Returning to Work By Helen Fitzgerald, CT After ... One employer called a grief therapist to help employees after a co-worker reported the death of ...

Novel competition 2015 : clowns and schoolboys, not to mention a footballer in love / Kärt Hellerma

Index Scriptorium Estoniae

Hellerma, Kärt, 1956-

2015-01-01

Eesti Kirjanike Liidu korraldatud romaanivõistluse võitis Armin Kõomägi romaaniga "Lui Vutoon", 2. koha sai Märt Lauri "Lahustumine", 3. koha Jim Ashilevi "Kehade mets" ning 4. koha Helen Eelranna "Suluseis"

Gorgias' and Isocrates' Use of the Encomium.

Science.gov (United States)

Poulakos, John

1986-01-01

Suggests that during the fifth and fourth centuries B.C. the encomium was not a rigid rhetorical genre, but a normative type both stable and elastic. Compares Gorgias and Isocrates' encomia of Helen. (MS)

Letters What causes an ice skater to accelerate? Note on the definitions of weight A-level physics is mathematical enough Correction to 'Confusion over the physics of circular motion'

Science.gov (United States)

2011-11-01

What causes an ice skater to accelerate? Hugh Fricker Note on the definitions of weight Nenad Stojilovic A-level physics is mathematical enough Helen Hare Correction to 'Confusion over the physics of circular motion'

Ajalooga aiad ja moodne harmoonia / Urmas Grishakov

Index Scriptorium Estoniae

Grišakov, Urmas, 1942-2013

2007-01-01

IT-firmade tehnopargist City West Business Campus (maastikulahendus: Martin Halliman), Saint Fiachari aiast, maastikuplaneerija William Robinsoni aiast, eraaiast Dublini eeslinnas Foxrockis (maastikuaednik Damian Keane), Helen Dilloni aiast Sandyford Roadil ja Killruddery lossipargist (1682) Iirimaal

"Hall mees" Linnateatris / Triin Sinissaar

Index Scriptorium Estoniae

Sinissaar, Triin

1999-01-01

Tallinn Linnateatri ja Raadioteatri ühislavastus "Hall mees" Gill Adamsi näidendi järgi, lavastaja Eero Spriit, osades Helene Vannari ja Väino Laes, kunstnik Kustav - Agu Püüman. Esietendus 22. okt

Uuslavastused Ugalas / Helle Leppik

Index Scriptorium Estoniae

Leppik, Helle

2007-01-01

Ugalas käib töö nelja uuslavastusega : Ott Aardam lavastab "Börs ja Börsitar", Helen Rekkor toob lavale "Nora/Maja", Peeter Tammearu suvelavastus on "Sirelikassid" ja Margus Vaher lavastab suvelavastuse "Naabri Mari"

Randomised controlled trial of the efficacy of misoprostol used as a ...

African Journals Online (AJOL)

Randomised controlled trial of the efficacy of misoprostol used as a cervical ripening agent prior to termination of pregnancy in the first trimester. Eric T M de Jonge, Rachel Jewkes, Jonathan Levin, Helen Rees ...

"Nimed marmortahvlil 2" ootab tegemist / Mihkel Raud

Index Scriptorium Estoniae

Raud, Mihkel, 1969-

2006-01-01

Stephen Frearsi mängufilm "Kuninganna" ("The Queen") : stsenarist Peter Morgan : kuninganna Elizabeth II kehastab Helen Mirren : Suurbritannia - Ameerika Ühendriigid - Itaalia 2006. Irooniline vihje teha ka Eestis poliitilise eliidi lepitamiseks rahvaga esimestest melodramaatilisi filme

Ascetismo, gênero e poder no Baixo Império Romano: Paládio de Helenópolis e o status das devotas cristãs Asceticism, gender and power in the Late Roman Empire: Palladius and the status of the holy women

Directory of Open Access Journals (Sweden)

Gilvan Ventura da Silva

2007-01-01

Full Text Available As diversas modalidades de ascetismo feminino que vigoraram nas comunidades cristãs ao longo dos três primeiros séculos do Império tenderão a se integrar numa nova experiência religiosa que começa a se esboçar por volta de 270 para alcançar uma expansão considerável no final do Mundo Antigo: o monacato. Mediante a análise da História Lausíaca, de Paládio de Helenópolis, obra escrita por volta de 420, investigamos a posição social das ascetas e o tipo de atuação que desempenharam no interior de um movimento dominado pelos homens, como foi o movimento monástico. Além disso, analisamos a capacidade das mulheres de exercer alguma modalidade de poder no âmbito das suas comunidades locais em comparação aos homens divinos cristãos do Baixo Império.The several kinds of female asceticism observed in the Roman Empire during the first three centuries A.D. will be gathered in a new religious experience that begins around 270 A.D.: the monasticism. Throughout the analysis of the Lausiac History, written by Palladius, bishop of Hellenopolis, in Bitinia, we aim at researching about the female ascetics social position and their actions as monastic movement members. Besides, we reflect over the kind of power women could exercise in their local communities compared with the holy men.

Systematische grondkaarteering van Zuid-Sumatra

NARCIS (Netherlands)

Idenburg, A.G.A.

1937-01-01

This systematic soil survey covers an area of about 50,000 sq.km, that consists of marshes, coastal plains, hills and mountains. Soils were classified as dry-land soils, marsh soils and peat soils, and subdivided as Residual and Sedimentary soils. Most soils are derived from liparitic, dacitic and

Rapid cooling rates at an active mid-ocean ridge from zircon thermochronology

Science.gov (United States)

Schmitt, Axel K.; Perfit, Michael R.; Rubin, Kenneth H.; Stockli, Daniel F.; Smith, Matthew C.; Cotsonika, Laurie A.; Zellmer, Georg F.; Ridley, W. Ian

2011-01-01

Oceanic spreading ridges are Earth's most productive crust generating environment, but mechanisms and rates of crustal accretion and heat loss are debated. Existing observations on cooling rates are ambiguous regarding the prevalence of conductive vs. convective cooling of lower oceanic crust. Here, we report the discovery and dating of zircon in mid-ocean ridge dacite lavas that constrain magmatic differentiation and cooling rates at an active spreading center. Dacitic lavas erupted on the southern Cleft segment of the Juan de Fuca ridge, an intermediate-rate spreading center, near the intersection with the Blanco transform fault. Their U–Th zircon crystallization ages (29.3-4.6+4.8 ka; 1δ standard error s.e.) overlap with the (U–Th)/He zircon eruption age (32.7 ± 1.6 ka) within uncertainty. Based on similar 238U-230Th disequilibria between southern Cleft dacite glass separates and young mid-ocean ridge basalt (MORB) erupted nearby, differentiation must have occurred rapidly, within ~ 10–20 ka at most. Ti-in-zircon thermometry indicates crystallization at 850–900 °C and pressures > 70–150 MPa are calculated from H2O solubility models. These time-temperature constraints translate into a magma cooling rate of ~ 2 × 10-2 °C/a. This rate is at least one order-of-magnitude faster than those calculated for zircon-bearing plutonic rocks from slow spreading ridges. Such short intervals for differentiation and cooling can only be resolved through uranium-series (238U–230Th) decay in young lavas, and are best explained by dissipating heat convectively at high crustal permeability.

Jaapani meditatsiooni, erootikat ja vägivalda / Margit Adorf

Index Scriptorium Estoniae

Adorf, Margit, 1974-

2011-01-01

Tallinna Kinomajas 25.-28. aug.-ni toimuvast Aasia sõltumatute filmide festivalist EVA - East via Asia. Festivali korraldaja Helen Merila. Festival sündis koostöös Zipangu Fest Japananarchy in UK peakorraldaja Jasper Sharpiga

Origin of the ca. 50 Ma Linzizong shoshonitic volcanic rocks in the eastern Gangdese arc, southern Tibet

Science.gov (United States)

Liu, An-Lin; Wang, Qing; Zhu, Di-Cheng; Zhao, Zhi-Dan; Liu, Sheng-Ao; Wang, Rui; Dai, Jin-Gen; Zheng, Yuan-Chuan; Zhang, Liang-Liang

2018-04-01

The origin of the Eocene shoshonitic rocks within the upper part of the extensive Linzizong volcanic succession (i.e., the Pana Formation) in the Gangdese arc, southern Tibet remains unclear, inhibiting the detailed investigations on the crust-mantle interaction and mantle dynamics that operate the generation of the coeval magmatic flare-up in the arc. We report mineral composition, zircon U-Pb age and zircon Hf isotope, whole-rock element and Sr-Nd-Hf isotope data for the Pana Formation volcanic rocks from Pangduo, eastern Gangdese arc in southern Tibet. The Pana volcanic rocks from Pangduo include basalts, basaltic andesites, and dacites. SIMS and LA-ICPMS zircon U-Pb dating indicates that the Pangduo dacites were erupted at 50 ± 1 Ma, representing the volcanic equivalent of the coeval Gangdese Batholith that define a magmatic flare-up at 51 ± 1 Ma. The Pangduo volcanic rocks are exclusively shoshonitic, differing from typical subduction-related calc-alkaline volcanic rocks. The basalts have positive whole-rock ƐNd(t) (+1.7) and ƐHf(t) (+3.8) with high Zr abundances (121-169 ppm) and Zr/Y ratios (4.3-5.2), most likely derived from the partial melting of an enriched garnet-bearing lithospheric mantle that was metasomatized by subduction-related components with input from asthenosphere. Compared to the basalts, similar trace elemental patterns and decreased whole-rock ƐNd(t) (-3.5 to -3.3) and ƐHf(t) (-2.5 to -1.6) of the basaltic andesites can be attributed to the input of the ancient basement-derived material of the central Lhasa subterrane into the basaltic magmas. The coherent whole-rock Sr-Nd-Hf isotopic compositions ((87Sr/86Sr)i = 0.7064-0.7069, ƐNd(t) = -6.0 to -5.2, ƐHf(t) = -5.6 to -5.0) and varying zircon ƐHf(t) (-6.0 to +4.1) of the dacites can be interpreted by the partial melting of a hybrid lower crust source (juvenile and ancient lower crust) with incorporation of basement-derived components. Calculations of zircon-Ti temperature and whole

Hydrothermal Alteration in an Acid-Sulphate Geothermal Field: Sulphur Springs, Saint Lucia

Science.gov (United States)

Joseph, E. P.; Barrett, T. J.

2017-12-01

Sulphur Springs is a vigorous geothermal field associated with the Soufrière Volcanic Centre in southern Saint Lucia. Bubbling hydrothermal pools are rich in sodium-calcium sulphate, with pHs of 3-7 and temperatures of 41-97ºC. Fumaroles have temperatures up to, and at times above, 100°C. Gases from bubbling pools and fumaroles have high contents of CO2 (601-993 mmol/mol) and H2S (3-190 mmol/mol). To investigate the nature and extent of hydrothermal alteration, detailed chemical analysis was carried out on 25 altered rocks, 10 sediments from pools and creeks in the main discharge area, and 15 little-altered rocks up to 2 km away from geothermal field. Eight altered samples were also analysed for stable isotope compositions, with mineralogy determined by X-ray diffraction and mineral liberation analysis. Least-altered host rocks comprise calc-alkaline feldspar-quartz-porphyritic dacites of near-uniform composition that form massive domes and volcaniclastic units. These rocks were emplaced 10-30 Ka ago (Lindsay et al. 2013). Within the geothermal field, the dacites have been highly altered to kaolinite, quartz, cristobalite, alunite, natroalunite, smectite, native sulphur, jarosite, gypsum and amorphous compounds. Muds from grey to blackish hydrothermal pools additionally contain iron sulphides, mainly pyrite. Despite intense alteration of the original dacites, Zr and Ti have remained essentially immobile, allowing the calculation of mass changes. Major depletions of Fe, Mg, Ca, Na and commonly Si occur over an area of at least 200 x 400 m. The most altered rocks also show losses of Al, light REE and Y, implying leaching by highly acidic waters. A few altered rocks have, however, gained Al together with Si and P. Also present are m-scale zones of silica + native sulphur, wherein the silica appears to represent a residue from the leaching of dacite, rather than a hydrothermal addition. Delta-34S values of samples containing mixtures of sulphates, native sulphur and

Uusi maalijaid Tartust

Index Scriptorium Estoniae

2007-01-01

Tartu Ülikooli maalikunsti eriala lõpetajate Veiko Klemmeri, Helen Kikkase ja Margit Lõhmuse tööde näitus Tartu Kunstimuuseumis ning Ronald Baumanni, Nadezhda Tshernobai ja Jäppe Johansoni näitus Tartu Kunstimajas

African Journal of Biotechnology - Vol 6, No 10 (2007)

African Journals Online (AJOL)

Anti-inflammatory activity of Ruta graveolens Linn on carrageenan induced paw edema in wistar male rats · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. M Ratheesh, A Helen ...

Õpetajaks õppimas / Mari-Helene Kaber

Index Scriptorium Estoniae

Kaber, Mari-Helene

2008-01-01

Humana People to people liikumise poolt loodud õpetajate koolitamise võrgustikust, mis tegutseb Angolas, Mosambiigis ja Malawis ja kus valmistatakse ette õpetajaid peamiselt maapiirkondade koolidesse

Uue oskuse võlu / Helen Talalaev

Index Scriptorium Estoniae

Talalaev, Helen

2009-01-01

Tutvustatakse kirjastuse TEA väljaantud õppekomplekte: Tomalin, Barry. Westminster English. Tallinn : TEA Kirjastus, 2009 ; Mangus, Inga. Vene keele õpik : algajale ja taasalustajale. Tallinn : TEA Kirjastus, 2008

"ARS 01", perspektiivide avamine / Helen Kivisoo

Index Scriptorium Estoniae

Kivisoo, Helen

2001-01-01

30. IX 2001-20. I 2002 Kiasmas kuuendat korda toimuvast rahvusvahelisest näitusest "ARS", kus Eestist osaleb Marko Mäetamm. Kuraatorid Tuula Arkio, Maaretta Jaukkuri, Patrik Nyberg, Jari-Pekka Vanhala. Teemaks "kolmas ruum". Näituse kajastamisest.

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Geochemical studies and modelling show that both volcanic and granitic magmas from the western part of the Johor National Park, Endau Rompin are different and probably have different sources. The geochemical plot suggests that both dacite/rhyolite and andesite probably have a common origin as in many of the ...

23. IV avati EKA galeriis projekti "Network Baltic" laureaatide graafikanäitus

Index Scriptorium Estoniae

2003-01-01

Rahvusvahelise kunstiprojekti "Network Baltic - a new dimension" algatas Grafikenshus Rootsis Mariefredis, Eestist osaleb EKA graafikaosakond, kuraator - Enno Ootsing. Näitusel esinevad Kevin Lytsen Taanist, Kaija Kesa Soomest, internetikonkursil ära märgitud Helen Tago ja Eveli Varik

Алексий II 1929-2008

Index Scriptorium Estoniae

2008-01-01

Aleksius II meenutavad: Kornelius, Tallinna ja kogu Eesti metropoliit ; Karin Jaani ; Marina Kaljurand ; Dmitri Medvedev, Venemaa president ; Helene Kamzol, Aleksius II sugulane ; Ain Seppik ; Vladimir Illjashevitsh ; Edgar Savisaar ; Jevgeni Tomberg ; Ene Ergma ; Toomas Hendrik Ilves, Eesti Vabariigi president

Viljandi kultuuriakadeemia tudengid lajatasid kolme tükiga / Andres Keil

Index Scriptorium Estoniae

Keil, Andres, 1974-

2007-01-01

Janusz Glowacki "Fortinbras jõi end täis" Viljandi Kultuuriakadeemia teatrikunsti eriala 6. lennu esituses, lavastaja Kalju Komissarov ja Sven Heiberg ; Ott Aardami "Börs ja börsitar" ja Henrik Ibseni "Nora/Maja", lavastaja Helen Rekkor

Viljandi paugutab kolme esietendusega / Andres Keil

Index Scriptorium Estoniae

Keil, Andres, 1974-

2007-01-01

Janusz Glowacki "Fortinbras jõi end täis" Viljandi Kultuuriakadeemia teatrikunsti eriala 6. lennu esituses, lavastaja Kalju Komissarov ja Sven Heiberg ; Ott Aardami "Börs ja börsitar" ja Henrik Ibseni "Nora/Maja", lavastaja Helen Rekkor

Medea’s Four Reasons

Directory of Open Access Journals (Sweden)

Marco Gemin

2014-11-01

Full Text Available The same motivations (eros, logos, bia, theos are attributed by Gorgias to Helen and by Euripides to Medea, which suggests the writers’ common intellectual ground, though the motivations are alternative in Gorgias, simultaneous in Euripides.

Kuula : Tuhkatriinu ooperilaval. Jazzkaare jõulujazz

Index Scriptorium Estoniae

2006-01-01

G. Rossini ooperi "Tuhkatriinu" esietendusest 10. nov. Rahvusooperis Estonia (peaosas Helen Lokuta). 11. jõulujazzist 29. nov.-14.dets. Eesti suuremates linnades. Prantsuse jazzlaulja Dee Dee Bridgewater'i kontserdist kavaga "J'ai deux amour" 2. dets. Estonia kontserdisaalis

Mõtteid raamatust / Koost. Heigi Aaviste

Index Scriptorium Estoniae

1995-01-01

Aut.: Maire Liivamets, Paul Luhtein, Paul-Eerik Rummo, Maksim Gorki, Johannes Semper, R.Descartes, Valmar Adams, Lilli Promet, Paul Rummo, Cicero, Honoré de Balzac, Aleksandr Pushkin, Epikuros, Debora Vaarandi, Arvi Siig, Helene Johani, Juhan Smuul, Friedebert Tuglas

Gender Studies transdisziplinär gestalten Designing Trans-Disciplinary Gender Studies

Directory of Open Access Journals (Sweden)

Sigrid Schmitz

2007-07-01

Full Text Available Robin Bauer und Helene Götschel stellen am Beispiel des Curriculum-Projektes „Degendering Science“ Inhalte und Didaktiken für transdisziplinäre Lehrkonzepte vor, um Naturwissenschaften und Gender Studies in einen konstruktiven Dialog zu bringen. Dieses Buch ist mit seinen vielen Beispielen eine Hilfestellung für alle Lehrenden der Gender Studies und es liefert wichtige Anregungen zu aktuellen Herausforderungen und Strategien bei der Institutionalisierung der Gender Studies.On the basis of the curriculum project, “Degendering Science,” Robin Bauer and Helene Götschel propose didactics and contents for trans-disciplinary pedagogical concepts that bring the natural sciences and Gender Studies into a constructive dialogue. Because of its many examples, this book will be helpful for all instructors of Gender Studies and offers important strategies and stimulation for approaching current challenges in the institutionalization of Gender Studies.

Wilding and weaving

DEFF Research Database (Denmark)

Stangeland, Siv Helene

2017-01-01

This doctoral research study is embedded in and developed through the creative practice Helen & Hards pursuit of making environmentally sound architecture in a professional market. The practice’s experience, through engaging in many projects, is that the current discourse on sustainable...... of developing, ongoing projects to tease out and explicate the embedded knowledge of the practice. The reational design practice of H&H can be understood within a triad of capacities: a sensitivity and respect for the singular, a nurturing of inclusive and emergent design development and a systemic agency...... in the context of the design practice, Helen & Hard (H&H). Furthermore, it investigates the relationship between an individuals creative access to this embodied knowledge and the systemic frameworks which can help to bring it forth in the collective endeavours of creating architecture. The research includes...

"Ethnography, Historiography, and the Making of History in the Tradition of the Anastenaria"

DEFF Research Database (Denmark)

Xygalatas, Dimitris

2011-01-01

In five villages of Northern Greece, the communities of the Anastenaria have a long tradi- tion of fire-walking rituals. The Anastenaria are Orthodox Christians, and their rituals are performed in honour of saints Constantine and Helen. However, the majority of Greek scholars have argued that the......In five villages of Northern Greece, the communities of the Anastenaria have a long tradi- tion of fire-walking rituals. The Anastenaria are Orthodox Christians, and their rituals are performed in honour of saints Constantine and Helen. However, the majority of Greek scholars have argued...... that these rituals originate from the ancient orgiastic cults of Dionysus. This theory was intentionally designed to serve specific political agendas, namely to prove the continuity of Greek civilization from ancient to modern Greece. Despite lacking any evidentiary support whatsoever, it became the dominant view...

Farmers on Welfare

DEFF Research Database (Denmark)

Knudsen, Ann-Christina

of deep archival research with nuanced political analysis makes it required reading for both historians and political scientists interested in this cornerstone of European integration." Helen Wallace, Centennial Professor, European Institute, London School of Economics and Political Science. "Farmers...

Frequency and severity of rheumatic heart disease in the catchment area of Gauteng hospitals, 1993-1995

NARCIS (Netherlands)

Clur, Sally-Ann

2006-01-01

OBJECTIVE: Identification of frequency and severity of rheumatic fever/rheumatic heart disease (RF/RHD) in the catchment area of Gauteng hospitals. DESIGN: A retrospective descriptive analysis using hospital-based computer databases. SETTING: Helen Joseph, Chris Hani Baragwanath and Johannesburg

Pärnu südalinna kavandatakse 17-korruselist uhket ärikeskust / Kristjan Jõevere

Index Scriptorium Estoniae

Jõevere, Kristjan

2006-01-01

Pärnu südalinna planeerimise ideekonkursi võitis töö "Flood", autorid eesti ja itaalia arhitektid Francesco De Luca, Paolo Gori, Romolo Nati, Mauro Olevano, Kerttu Koll, Antonio Capasso, Giuliana Mancinelli Bonafaccia ja Helen Sooväli

No conflict between SLAC and Japan's KEK

CERN Multimedia

2000-01-01

Letter from Helen Quinn from SLAC arguing that an article in Nature distorted her comments on the relationship between KEK and SLAC over their separate projects looking at CP violation. The author of the original article replies (1/2 page).

McCormick to Aid Frederick National Laboratory in Developing RAS Cancer Genetics Initiative | Frederick National Laboratory for Cancer Research

Science.gov (United States)

Frank McCormick, Ph.D., director of the Helen Diller Family Comprehensive Cancer Center at the University of California, San Francisco, and associate dean of the UCSF School of Medicine, has signed a consulting agreement with SAIC-Frederick Inc. to w

Richard Avedon ja Annie Leibovitz laulsid kaanonit / Marika Alver

Index Scriptorium Estoniae

Alver, Marika

2008-01-01

Richard Avedoni (1923-2004) retrospektiivnäitusest (fotod aastatest 1946-2004) kuraator Helle Crenzien (Lousiana Kaasaegse Kunsti muuseum Taanis), millega kaasnes ka Helen Whitney film "Richard Avedon : darkness and light" ja Annie Leibovitzi (1949) suurprojektist "A photographer's life 1990-2005" Pariisis

Help History Come Alive with Mannequins.

Science.gov (United States)

Wisdom, Cynthia Newman

1994-01-01

Describes a teacher's use of life-size mannequins donated by a dress shop to teach students about historical figures and periods. Christopher Columbus, Florence Nightingale, Abraham Lincoln, George Washington Carver, and Helen Keller, among other historical figures, have been portrayed. (MDM)

76 FR 60128 - Senior Executive Service; Legal Division Performance Review Board

Science.gov (United States)

2011-09-28

...; M.J.K. Maher, Jr., Deputy Assistant General Counsel (Enforcement & Intelligence); Margaret V... Counsel; Mark Monborne, Assistant General Counsel (Enforcement & Intelligence); Helen Morrison, Deputy Benefits Tax Counsel; Kevin Rice, Chief Counsel, Bureau of Engraving and Printing; Daniel P. Shaver, Chief...

New perspectives on the eruption of 1912 in the valley of ten thousand smokes, Katmai National Park, Alaska

Science.gov (United States)

Hildreth, W.

1987-01-01

New data extend our understanding of the 1912 eruption, its backfilled vent complex at Novarupta, and magma-storage systems beneath adjacent stratovolcanoes. Initial Plinian rhyolite fallout is confined to a narrow downwind sector, and its maximum thickness may occur as far as 13 km from source. In contrast, the partly contemporaneous rhyolite-rich ash flows underwent relatively low-energy emplacement, their generation evidently being decoupled from the high column. Flow veneers 1-13 m thick on near-vent ridge crests exhibit a general rhyolite-to-andesite sequence like that of the much thicker valley-confined ignimbrite into which they merge downslope. Lithics in both the initial Plinian and the ignimbrite are predominantly fragments of the Jurassic Naknek Formation, which extends from the surface to a depth of ca. 1500 m. Absence of lithics from the underlying sedimentary section limits to 100 m thick near source and 10 m thick 3 km away, which dip back into an inner vent <0.5 km wide, nested inside the earlier vent funnel of the ignimbrite. The dacite fallout is poor in Naknek lithics but contains abundant fragments of vitrophyre, most of which was vent-filling, densely welded tuff reejected during later phases of the 3-day eruption. Adjacent to the inner vent, a 225-m-high asymmetrical accumulation of coarse near-vent ejecta is stratigraphically continuous with the regional dacite fallout. Distensional faulting of its crest may reflect spreading related to compaction and welding. Nearby andesite-dacite stratovolcanoes, i.e., Martin, Mageik, Trident, and Katmai, display at least 12 vents that define a linear volcanic front trending N65??E. The 1912 vent and adjacent dacite domes are disposed parallel to the front and ca. 4 km behind it. Mount Griggs, 10 km behind the front, is more potassic than other centers, taps isotopically more depleted source materials, and reflects a wholly independent magmatic plumbing system. Geochemical differences among the

Magmatic storage conditions, decompression rate, and incipient caldera collapse of the 1902 eruption of Santa Maria Volcano, Guatemala

Science.gov (United States)

Andrews, Benjamin J.

2014-08-01

Phase equilibria experiments and analysis of natural pumice and phenocryst compositions indicate the 1902 Santa Maria dacite was stored at ~ 140-170 MPa and 840-850 °C prior to eruption. H2O-saturated, cold-seal experiments conducted in vessels with an intrinsic log fO2 of NNO + 1 ± 0.5 show that the natural phase assemblage (melt + plagioclase + amphibole + orthopyroxene + Fe-Ti oxides + apatite) is stable from approximately 115-140 MPa at temperatures below ~ 825 °C, to ~ 840-860 °C at 150 MPa, to > 850 and Ridolfi et al., 2010) applied to experimental samples suggest two populations of amphiboles, phenocrysts grown during the experiments and inherited xenocrysts, but the pressure-temperature conditions returned by the geothermobarometer are routinely > 50 MPa and > 50 °C greater than experimental run conditions; precise estimates of magmatic conditions based solely upon amphibole composition are likely inaccurate. The experimental results and analysis of natural crystals suggest that although the natural amphiboles likely record a broad range of magmatic conditions, only the lower bounds of that range reflect pre-eruptive storage conditions. Comparison of Santa Maria microlite abundances with decompression experiments examining other silicic systems from the literature suggests that the 1902 dacite decompressed at the rate of ~ 0.005 to 0.01 MPa/s during the eruption. Applying the decompression rate with the previously described eruption rate of approximately 2-3 × 108 kg/s (Williams and Self, 1983; Carey and Sparks, 1986) to the conduit model CONFLOW reveals that the eruption conduit was dike-like with an along-strike length > 1 km. Despite depositing ~ 20 km3 of dacite tephra (equivalent to ~ 8.5 km3 magma), the 1902 eruption did not form an obvious caldera. This work suggests that collapse of the dike-like conduit terminated the eruption, preventing full caldera collapse.

The 13 ka Pelée-Type Dome Collapse at Nevado de Toluca Volcano, México.

Science.gov (United States)

D'Antonio, M.; Capra, L.; Sarocchi, D.; Bellotti, F.

2007-05-01

The Nevado de Toluca is an active volcano located in the central sector of the Trans-Mexican Volcanic Belt, 80 km southwest of Mexico City. Activity at this andesitic to dacitic stratovolcano began ca. 2.6 Ma ago. During the last 42 ka, the volcano has been characterized by different eruptive styles, including five dome collapses dated at 37, 32, 28, 26, and 13 ka and five Plinian eruptions at 42 ka, 36 ka, 21.7 ka, 12.1 ka and 10.5 ka. The 13 ka dome collapse is the youngest event of this type, and originated a 0.11 km3 block-and-ash flow deposit on the north-eastern sector of the volcano. The deposit consists of two facies: channel-like, 10 m thick, monolitologic, that is composed of up to five units, with decimetric dacitic clasts set in a sandy matrix; and a lateral facies that consists of a gray, sandy horizon, up to 4 m thick, with a 30 cm-thick surge layer at the base. The main component is a dacitic lava, with different degree of vesciculation, with mineral association of Pl-Hbl-Opx. Plagioclases show two different textures: in equilibrium, with normal zoning (core = An37-64.3, rim = An30.7-45.8) or with spongy cellular texture with inverse zoning (core = An38-43.5, rim = An45-51.2). Hornblende is normally light green, barren of oxidation. The rock matrix contains up to 53 perc. of glass with abundant microlites, indicating over-pressure on the crystallizing magma and a rapid expulsion. All these stratigraphic and petrographic features indicate that the dome was quickly extruded on the summit of the volcano, probably triggered by a magma mixing process, and its collapse was accompanied by an explosive component, being classified as a Pelée-type event.

Volcanic geology and geochemistry of Motuhora (Whale Island), Bay of Plenty, New Zealand

International Nuclear Information System (INIS)

Burt, R.M.; Cole, J.W.; Vroon, P.Z.

1996-01-01

Motuhora (Whale Island) lies c. 11 km offshore from Whakatane in the Bay of Plenty, New Zealand, and comprises tuffaceous marine sediments of the Camp Bay and Motuhora Formations separated by lavas, volcanic breccias, and slope-wash deposits of the Whale Volcanics. Whale Volcanics can be divided into East Dome, Central Dome Complex, and Pa Hill Dome. East Dome is a flow banded, chaotically jointed dacite that is probably extrusive. Central Dome comprises lava flows, and extensive volcanic breccias and tuffs which thicken into a local depression to the north of the central high, suggesting rapid growth and erosion of the dome. Pa Hill Dome is largely intrusive into Camp Bay Formation, although blocks of Pa Hill dacite in an upper slope-wash cobble bed suggest it was partially extrusive. The lavas are porphyritic with phenocrysts of plagioclase, orthopyroxene, and titanomagnetite with subordinate clinopyroxene and amphibole (particularly in Pa Hill Dome), and rare biotite. Rounded or broken and embayed quartz crystals are found in the Central Dome Complex and Pa Hill domes. Magmatic xenoliths are common in all lavas. Chemically the lavas are medium-K, calc-alkaline andesites and dacites, and show relative LILE enrichment and HFSE depletion typical of arc volcanics. Isotopically, samples tend to have more radiogenic Sr and less radiogenic Nd than volcanics from neighbouring White Island. It is likely that Motuhora lavas were formed by a multi-stage process involving partial melting of N-MORB-type mantle that had been fluxed by fluids rich in incompatible elements derived from the dehydrating downgoing slab and followed by crystal fractionation of the magma. As the magma rose through the lower continental crust it was contaminated, probably by Torlesse metasediment. Petrographic textures and mineral chemistry indicate that magma mixing, while in an upper crustal magma chamber, is the norm for Motuhora lavas. (author). 69 refs., 12 figs., 2 tabs

Magma evolution in the Pliocene Pleistocene succession of Kos, South Aegean arc (Greece)

Science.gov (United States)

Pe-Piper, Georgia; Moulton, Ben

2008-11-01

This study investigates the petrogenesis of Pliocene-Quaternary andesites, dacites and rhyolites of the island of Kos. These volcanic rocks differ from other volcanic centres in the South Aegean arc in the narrow range of Pliocene volcanic products, the abundance of high-silica rhyolite, the lower ɛNd for a given Sr isotope composition, and greater depth to the subducting slab. Pliocene and early Pleistocene dacite stocks and rhyolite domes are succeeded by younger tuffs, notably the 0.16 Ma Kos Plateau Tuff derived from a super-eruption of an andesite stratocone now subsided beneath the sea south of Kos. Volcanic products in tuffs have been sampled from lithic clasts. Andesite, dacite and rhyolite all have ɛNd ˜+ 1.5 to -1.5 and 86Sr/ 87Sr ˜ 0.7042; this unusual composition is argued to be the result of subduction of sediments derived from the River Nile. All rock types show structures indicative of widespread magma mixing, including complexly zoned plagioclase, clinopyroxene and amphibole containing glass inclusions of trachyte and rhyolite compositions. The observed rocks result from fractionation and mixing of three principal magma types: (a) calc-alkaline high-Al basalt that fractionated to andesite at the base of crust; (b) partially melted metabasaltic amphibolite underplated at the base of crust, that fractionated to produce high-SiO 2 rhyolite; and (c) a minor component of trachytic magma from partial melting of enriched subcontinental lithospheric mantle. The complexly zoned phenocrysts with glass inclusions provide specific evidence for mixing of these three components. Specifically, it was the emplacement of the andesite into a voluminous rhyolite magma in a mid-crustal magma chamber that led to the explosive Kos Plateau Tuff super-eruption.

Geology and zircon fission track ages of volcanic rocks in the western part of Hoshino gold area, Fukuoka Prefecture, Japan

Energy Technology Data Exchange (ETDEWEB)

Belhadi, Ahmed; Himeno, Osamu; Watanabe, Koichiro; Izawa, Eiji [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering

1999-12-01

The Hoshino gold area is located in the western part of the Hohi volcanic zone, northern Kyushu. Volcanic rocks in this area vary from andesitic rocks in the north to dacite and rhyolite in the South. The basement is constituted by metamorphic rocks of pre-Cretaceous age. The volcanic rocks of Pliocene age were subdivided into eight volcanic units. Seven fission track ages of zircons from five volcanic units have been determined, using the external detector method. The age data obtained, combined with some previously reported ages, show that two main volcanic activities have occurred in the area. The first volcanic activity took place around 4.3 Ma, and resulted into the deposition of the Hoshino Andesite and the Ikenoyama Conglomerate. The second main volcanism started around 3.5 Ma, and was characterized by the eruption of the Shakadake Andesite and the Reiganji Andesite at the early stage, then, by more acidic rocks of the Takeyama Andesite, the Hyugami Dacite and the Kuroki Rhyolite at the later stage. The main volcanism in the area ceased around 2.6 Ma. (author)

Geologic map of the northwest quarter of the Bullfrog 15-minute quadrangle, Nye County, Nevada

International Nuclear Information System (INIS)

Maldonado, F.

1990-01-01

This study of the northwest quarter of the Bullfrog 15-minute quadrangle was undertaken to determine the stratigraphy and structural setting as part of a regional study in cooperation with the US Department of Energy. Geologic data were plotted on aerial photographs at a scale of 1:24,000. Alluvial deposits were mapped on aerial photographs, and, in some cases, field-checked. Thickness of bedded tuff as shown on the map and in the geologic sections was exaggerated in some cases in order to show distribution. Thicknesses of units are approximate due to varying degrees of internal deformation. A detachment fault is defined for this study as ''...a low-angle normal fault that formed at a low angle, has significant displacement, and is of subregional extent.'' Nomenclature for lavas and igneous dikes is based on field identifications, guided by some petrographic determinations; latite-type rocks are termed ''latitic, '' dacite-type, ''dacitic,'' and so forth. Age determinations where indicated for the rock units have been corrected for new K-Ar constants. 17 refs

Petrogenesis of Mount Rainier andesite: magma flux and geologic controls on the contrasting differentiation styles at stratovolcanoes of the southern Washington Cascades

Science.gov (United States)

Sisson, Thomas W.; Salters, V.J.M.; Larson, P.B.

2013-01-01

Quaternary Mount Rainier (Washington, USA) of the Cascades magmatic arc consists of porphyritic calc-alkaline andesites and subordinate dacites, with common evidence for mingling and mixing with less evolved magmas encompassing andesites, basaltic andesites, and rarely, basalts. Basaltic andesites and amphibole andesites (spessartites) that erupted from vents at the north foot of the volcano represent some of Mount Rainier's immediate parents and overlap in composition with regional basalts and basaltic andesites. Geochemical (major and trace elements) and isotopic (Sr, Nd, Pb, O) compositions of Mount Rainier andesites and dacites are consistent with modest assimilation (typically ≤20 wt%) of evolved sediment or sediment partial melt. Sandstones and shales of the Eocene Puget Group, derived from the continental interior, are exposed in regional anticlines flanking the volcano, and probably underlie it in the middle to lower crust, accounting for their assimilation. Mesozoic and Cenozoic igneous basement rocks are unsuitable as assimilants due to their high 143Nd/144Nd, diverse206Pb/204Pb, and generally high δ18O.

Oma ala meistriks saab igaüks isemoodi / Anna-Liisa Mets

Index Scriptorium Estoniae

Mets, Anna-Liisa

2014-01-01

Selgusid kutsemeistrivõistluse "Noor meister 2014" parimad. Edukalt esinenud õppurid meisterkondiiter Helen Laht, ehituspuussepp Mirko Pruus, logistik Karl-Erik Maripuu, keskkonnatehnika lukksepp Robert Born, elektrik Tiit Talts ja müürsepp Sander Hindrikus räägivad oma ametiõpingutest ja tulevikuplaanidest

Eesti klaasikunstnik lummab ameeriklasi / Meeli Kõiva ; interv. Robert Vaks

Index Scriptorium Estoniae

Kõiva, Meeli

1998-01-01

Meeli Kõiva, kellega intervjuu ja kelle vitraažide fotod ilmusid Ameerika Ühendriikide vitraažikunstnike Assotsiatsiooni ajakirja "Stained Glass" talvenumbris (Helene Weiss "Unistused transparentsest ruumist") vitraažist, selle kasutamisest Ameerikas ja Eestis, oma tööde lähtekohtadest.

Building a Better Strategic Analyst: A Critical Review of the U.S. Army’s All Source Analyst Training Program

Science.gov (United States)

2008-05-15

intelligence enterprise to describe the idea used in this monograph. 12 David Brooks, “The Elephantiasis of Reason,” The Atlantic Monthly. (January/February... Elephantiasis of Reason”. The Atlantic Monthly. (January/February, 2003). Boyd, Dennis & Bee, Helen. 2006. Lifespan Development. Fourth Edition. Allyn

Võru linnagaleriis avati kolm uut näitust

Index Scriptorium Estoniae

2009-01-01

26. oktoobrist 20 novembrini on Võru Linnagaleriis avatud Ruti Jõgi joonistuste ja Aivar Rumvoldi maalide näitus "Koos. Omaette", Marek Hämmelbergi isikunäitus "Tuvi ämm" ning grupi Sigmund Freud (Liina Guiter, Katrin Tees, Helen Melesk) näitus "Keemia"

What’s Sexual Violence Got to do with the Economy? The case of the DRC

NARCIS (Netherlands)

S. Cruz (Serena); H.M. Hintjens (Helen)

2015-01-01

markdownabstractIn this paper, Serena Cruz and Helen Hintjens propose that in the Democratic Republic of Congo the unholy alliance of economic interests, forced labour, sexual predation, and killings that King Leopold of Belgium established from 1884 onwards resulted in structures of predatory,

Erasmus

Index Scriptorium Estoniae

2013-01-01

Eesti kõrgkoolide üliõpilaste õpirändest Erasmus programmi raames. Tartus korraldati rahvusvaheline konverents "Üliõpilasmobiilsuse erinevad tahud", kus lisaks teistele jagasid oma kogemusi Tallinna Ülikooli üliõpilane Helen Margus ja Tallinna Ülikooli õppejõud Sirje Virkus

Ecology for conserving our sirenians

Science.gov (United States)

Bonde, Robert K.

2012-01-01

Review of: Ecology and conservation of the sirenia: dugongs and manatees. Helene Marsh, Thomas J. O'Shea and John E. Reynolds III. Cambridge University Press, Cambridge, 2012, 521 pp, ISBN 978-0-521-88828-8, US$135 and 978-0-521-71643-7, US$65.

Mõnda mõnusat teismelise tüdruku lugemislauale / Aidi Vallik

Index Scriptorium Estoniae

Vallik, Aidi, 1971-

2007-01-01

Kuuest tüdrukuteraamatust: Diana Leesalu "Kaks grammi hämaruseni", Helen Crossi "Minu armastuse suvi", Ann Brashare'i "Rändavate Pükste õeskond", Eva Ibbotsoni "Reis Merejõele", Sue Limbi "Tüdruk, 15, sarmikas, kuid sõge", Louise Rennisoni "Poisid, stringid ja ogar kass"

First world war: 'The first big test of professional nursing'.

Science.gov (United States)

Trueland, Jennifer

2017-08-16

When Helen Fairchild, a young nurse in Pennsylvania, volunteered to take her skills to Europe in the first world war, she was glad to go but felt sorry for her mother. 'If she would only not worry so much', she wrote to her brother Ned.

Valuing the Place of Young People with Learning Disabilities in the Arts

Science.gov (United States)

Goddard, Jennifer

2015-01-01

Methodologies of embodied learning, radical pedagogies and applied drama offer a lens through which to investigate the empowerment of young people with learning disabilities in Northern Ireland, thus counteracting more traditional, disempowering methods. According to Helen Nicholson, the "participatory, dialogic and dialectic qualities as…

78 FR 77673 - Proposed CERCLA Administrative Cost Recovery Settlement; Cadie Auto Salvage Site, Belvidere...

Science.gov (United States)

2013-12-24

... Recovery Settlement; Cadie Auto Salvage Site, Belvidere, Boone County, Illinois AGENCY: Environmental... Auto Salvage Site in Belvidere, Boone County, Illinois with the following settling party: Helen E... reference the Cadie Auto Salvage Site, Belvidere, Boone County, Illinois and EPA Docket No. and should be...

Blair üritab muuta USA Euroopa-meelsemaks / Neeme Raud

Index Scriptorium Estoniae

Raud, Neeme, 1969-

2004-01-01

USA presidendi George W. Bushi ja Suurbritannia peaministri Tony Blairi kohtumine Valges Majas. Blairi parteikaaslase Helen Jacksoni kriitika Blairi USA-poliitika kohta. Suurbritannia endise välisministri Robin Cooki sõnul on USA ja Euroopa poliitilised väärtushinnangud pigem lahknemas kui ühtimas

Kormašov puhus Leonardo autoportree intriigi lõkkele / Tiiu Leis

Index Scriptorium Estoniae

Leis, Tiiu

2010-01-01

Kadrioru Kunstimuuseumis eksponeeritakse Leonardo da Vinci arvatavat autoportreed. Lõuna-Itaalia erakogust leitud maali uurimisprotsessi kaasati Tallinna Ülikooli kunstiosakonna juhataja, maali ja maalitehnoloogia õppejõud Orest Kormašov, kes jagab selgitusi maali uuringute kohta. Ekspertiisis osales ka Eesti Kunstiakadeemia graafilise disaini tudeng Helen Kokk

"Siin me oleme!" = "Here we are!" / Hannes Praks

Index Scriptorium Estoniae

Praks, Hannes, 1973-

2013-01-01

Maarjamäe lossis avatud näituse "Siin me oleme! Eesti filmi esimene sajand" kujundusest. Autorid: Hannes Praks, Toomas Pääsuke, Helen Sarapuu. Graafiline disain: Stella Skulatšjova, Kerli Virk. Sisearhitekti ja ESLi aastapreemia žürii liikme Tea Tammelaane arvamus

Väikeste naiste oma ruum / Katrin Kivimaa

Index Scriptorium Estoniae

Kivimaa, Katrin, 1969-

1998-01-01

Näitus "(Meta)Dialoog" A. H. Tammsaare muuseumis ja Kastellaanimaja galeriis. Kuraator Reet Varblane. Osalejad : Kiwa, Mari Laanemets, Helen ? (Helena) Lehtmets, Ele Praks, Piia Ruber, Liina Siib, Helena Palm, Kadi Soosalu, Killu Sukmit. Kõik tööd näitusel käsitlevad naist.

ACCUMULATION AND TISSUE DISPOSITION OF PARTICLE ASSOCIATED ELEMENTS IN THE RAT AFTER REPEATED INTRATRACHAEL ADMINISTRATION OF SOURCE PARTICLES

Science.gov (United States)

The goal of this study was to determine the fate of source particle tracer elements following repeated intratracheal instillation (IT) to rats. PM samples comprised Mt. St. Helens ash (MSH) with no water-soluble metals, and oil flyash emission PM (EPM) with water-leachable solubl...

Selvskade som selvteknologi

DEFF Research Database (Denmark)

Rasmussen, Anna Lanken; Rasmussen, Svend Aage

2016-01-01

livshandlinger” – selvskade som social lidelse. Herefter argumenterer forfatterne med udgangspunkt i et feltstudie af Helen Gremillion for vigtigheden af at kaste et kritisk blik på behandlingskultur. Denne kritik videreføres i et afsnit om den postmoderne udfordring i forhold til selvskade. Afslutningsvis...

Kolm väärt väljapanekut Võru Linnagaleriis / Andrus Raag

Index Scriptorium Estoniae

Raag, Andrus, 1982-

2009-01-01

Helen Meleski, Katrin Teesi ja Liina Guiteri (ühisnimi Sigmund Freud) näitus "Keemia", Ruti Jõgi joonistuste ja Aivar Rumvoldi maalide näitus "Koos. Omaette", Marek Hämmelbergi (pseudonüüm Marek) joonistuste näitus "Tuvi ämm" 20. novembrini

The onset of the volcanism in the Ciomadul Volcanic Dome Complex (Eastern Carpathians): Eruption chronology and magma type variation

Science.gov (United States)

Molnár, Kata; Harangi, Szabolcs; Lukács, Réka; Dunkl, István; Schmitt, Axel K.; Kiss, Balázs; Garamhegyi, Tamás; Seghedi, Ioan

2018-04-01

Combined zircon U-Th-Pb and (U-Th)/He dating was applied to refine the eruption chronology of the last 2 Myr for the andesitic and dacitic Pilişca volcano and Ciomadul Volcanic Dome Complex (CVDC), the youngest volcanic area of the Carpathian-Pannonian region, located in the southernmost Harghita, eastern-central Europe. The proposed eruption ages, which are supported also by the youngest zircon crystallization ages, are much younger than the previously determined K/Ar ages. By dating every known eruption center in the CVDC, repose times between eruptive events were also accurately determined. Eruption of the andesite at Murgul Mare (1865 ± 87 ka) and dacite of the Pilişca volcanic complex (1640 ± 37 ka) terminated an earlier pulse of volcanic activity within the southernmost Harghita region, west of the Olt valley. This was followed by the onset of the volcanism in the CVDC, which occurred after several 100s kyr of eruptive quiescence. At ca. 1 Ma a significant change in the composition of erupted magma occurred from medium-K calc-alkaline compositions to high-K dacitic (Baba-Laposa dome at 942 ± 65 ka) and shoshonitic magmas (Malnaş and Bixad domes; 964 ± 46 ka and 907 ± 66 ka, respectively). Noteworthy, eruptions of magmas with distinct chemical compositions occurred within a restricted area, a few km from one another. These oldest lava domes of the CVDC form a NNE-SSW striking tectonic lineament along the Olt valley. Following a brief (ca. 100 kyr) hiatus, extrusion of high-K andesitic magma continued at Dealul Mare (842 ± 53 ka). After another ca. 200 kyr period of quiescence two high-K dacitic lava domes extruded (Puturosul: 642 ± 44 ka and Balvanyos: 583 ± 30 ka). The Turnul Apor lava extrusion occurred after a ca. 200 kyr repose time (at 344 ± 33 ka), whereas formation of the Haramul Mic lava dome (154 ± 16 ka) represents the onset of the development of the prominent Ciomadul volcano. The accurate determination of eruption dates shows that the

DANCE Your Way to Healthier Lungs

Science.gov (United States)

... good it feels to move your body to music. It exhilarates you physically and mentally. It makes you feel alive. But Helen Sorenson, a registered respiratory therapist, gerontologist, and assistant professor at the University of Texas Health Science Center at San Antonio, TX, has another version ...

The Modern First Lady and Public Policy: From Edith Wilson through Hillary Rodham Clinton.

Science.gov (United States)

Black, Allida M.

2001-01-01

Discusses the role in and influence on public policy of twentieth century First Ladies including Edith Roosevelt, Helen Taft, Ellen Wilson, Edith Wilson, Florence Harding, Lou Henry Hoover, Eleanor Roosevelt, Jacqueline Kennedy, Lady Bird Johnson, Rosalynn Carter, Nancy Reagan, Barbara Bush, and Hillary Rodham Clinton. (CMK)

How Sex Attitudes Develop

Science.gov (United States)

Arnstein, Helene S.

1976-01-01

Excerpt from "The Roots of Love" (Helene S. Arnstein, 1975). Book is concerned with feelings that are part of child's developmental stages. Included in excerpt are: genital self-discovery, masturbation, discovery of sex differences, and birth fantasies. Stresses importance of parent's feelings which are communicated to child.

Professor Gerhard Rägo nimelised medalid tema 115. sünniaastal / Tiit Lepmann

Index Scriptorium Estoniae

Lepmann, Tiit, 1949-

2012-01-01

Tänavused medalisaajad: Mare-Lee Hamer - Nõo Reallgümnaasiumi matemaatikaõpetaja ; Ülle Hüva - Tartu Hugo Treffneri Gümnaasiumi matemaatikaõpetaja ; Helen Kaasik - Tallinna Reaalkooli matemaatikaõpetaja ; Ellen Redi - Tallinna Ülikooli matemaatika-loodusteaduskonna dotsent ; Tiia Toobal - Pärnu Koidula Gümnaasiumi matemaatikaõpetaja

Eesti Kunstiakadeemia tootedisaini eriala magistritööde kaitsmised 3. juulil...

Index Scriptorium Estoniae

2001-01-01

Kaitsmisele tulevad tööd: Liis Ira "Säästev tootearendus ja tekstiilide recycling" (juh. Tiina Laurila); Ruth-Helene Kaasiku "Energiasäästmisvõimalused välisvalgustuses" (juh. Arvo Pärenson); Maria Pukk'i "Linnainventari kohereerumine vahelduvates maastikes" - "Green Way" (juh. A. Pärenson).

"Translated, It Is: …"--An Ethics of Transreading

Science.gov (United States)

Zhang, Huiwen

2014-01-01

Inspired by Friedrich Nietzsche's idea of philology and William Gass's concept of transreading, Huiwen (Helen) Zhang employs "transreader" to suggest the integration of four roles in one: reader, translator, writer, and scholar. "Transreader" recognizes that close reading, literary translation, creative writing, and…

Asie du sud | Page 97 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

The introduction and testing of small farm machineries such as iron plows, threshers, and dehullers (which remove the husk from the millet seed) have significantly ... Since 1998, Helen Keller International (HKI) has supported women in homestead-level production of nutrient-rich fruits, vegetables, and animal source foods.

Doing Home Works

DEFF Research Database (Denmark)

Nelund, Sidsel

2013-01-01

of aesthetic analysis of artworks and ethnographic fieldwork (Georgina Born); and 3) the use of generative ethnographic stories as a writing tool (Helen Verran). The latter two, especially, are then employed in analysing the Beirut-based extended exhibition, ‘Home Works: A Forum on Cultural Practices...

Leisure and Aging: An International Perspective.

Science.gov (United States)

Kaplan, Max, Ed.

This document contains an international collection of national position papers on leisure and aging. The following papers are included in the first section: "'Active' and 'Passive' Constructs of Elderly" (Max Kaplan); "Recreation and the Aged: A Review" (Helen J. Threlfall); "The Elderly in Bolivia"; "The Elderly…

Extrême-Orient | Page 92 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

The introduction and testing of small farm machineries such as iron plows, threshers, and dehullers (which remove the husk from the millet seed) have significantly ... Since 1998, Helen Keller International (HKI) has supported women in homestead-level production of nutrient-rich fruits, vegetables, and animal source foods.

South Asia | Page 97 | IDRC - International Development Research ...

International Development Research Centre (IDRC) Digital Library (Canada)

The introduction and testing of small farm machineries such as iron plows, threshers, and dehullers (which remove the husk from the millet seed) have significantly ... Since 1998, Helen Keller International (HKI) has supported women in homestead-level production of nutrient-rich fruits, vegetables, and animal source foods.

Retten til privathed i det danske sundhedsvæsen

DEFF Research Database (Denmark)

Bjerre, Hanne Pihl; Juel Vang, Katrine

2014-01-01

på en tilfredsstillende måde. Artiklens primære perspektiv er deontologisk, men for at nuancere vores diskussion inddrages lejlighedsvist også utilitaristiske argumenter. Endvidere inddrages i artiklen Helen Nissenbaum, Tom L. Beauchamp og James F. Childress samt John Rawls. I artiklen vil tre...

Fictional Narrative as Resistant Argument in Early Twentieth-Century Feminist Writing.

Science.gov (United States)

Allen, Julia M.

Helen Forbes, in her short story "The Hunky Woman," written in 1916 for "The Masses," an eclectic Socialist magazine, undermines particular categorical propositions. By using narration with a shifting of narrative voice, Forbes calls into question the validity of the traditional teaching of argumentation. Forbes demonstrates…

Best Not Forget Lesbian, Gay, Bisexual, and Transgender Themed Children's Literature: A Teacher's Reflections of a More Inclusive Multicultural Education and Literature Program

Science.gov (United States)

Flores, Gabriel

2016-01-01

For many years, educational practitioners have been implementing multicultural literature about African-American, Asian, and Latino families. Teachers have also presented literature about great leaders, such as Martin Luther King Jr. and Helen Keller. However, the same cannot be said about literature depicting lesbian, gay, bisexual, and…

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics; Volume 90; Issue 2. Thermal phenotypic plasticity of body size in Drosophila melanogaster: sexual dimorphism and genetic correlations. Jean R. David Amir Yassin Jean-Claude Moreteau Helene Legout Brigitte Moreteau. Research Article Volume 90 Issue 2 August 2011 pp 295-302 ...

Science stand-up at CERN

CERN Multimedia

Stephanie McClellan

2013-01-01

Supported by host Helen Keen from BBC4’s "It is Rocket Science", six amateur performers from CERN (Sam Gregson, Alex Brown, Benjamin Frisch, Claire Lee, Hugo Day and Clara Nellist) were joined on stage by geek-pop sensation Jonny Berliner and comedians Pierre Novellie and Lieven Scheire for a night of science stand-up comedy.   Host Helen Keen starts off the comedy event. (Image: Piotr Traczyk). Like the genesis of most great things, the LHComedy event began as an idea. Sam Gregson, a PhD student at CERN, had been a regular at the Cambridge Bright Club. This public engagement event promotes scientists’ research through stand-up comedy. Sam thought, “If people came to watch Bright Club at Cambridge and enjoyed the research, why can’t we do it at the biggest scientific experiment in the world?” Sam’s idea gained momentum after being introduced to FameLab participants at CERN. Similar to Bright Club, FameLab is a com...

Transformative Processes in Environmental Education: A Case Study

African Journals Online (AJOL)

social–ecological system, and on an environmental-education initiative that aimed to ... Helen Fox, Tally Palmer, Unilever Centre of Water Quality, ... Two methodologies supported insights shared in this paper: a contextual profile and action ..... lead and initiate action, as well as share decision-making, through an open ...

Nora ehk elu võimalikkusest naisena perekonnas, teatris ja kapitalismis / Anneli Saro

Index Scriptorium Estoniae

Saro, Anneli, 1968-

2008-01-01

Naistegelasest teatrist järgnevate lavastuste põhjal: Helen Rekkori lavastusest "Nora/Maja" Henrik Ibseni "Nukumaja" järgi Ugala teatris ja Elfriede Jelineki "Mis juhtus pärast seda, kui Nora oma mehe maha oli jätnud ehk Ühiskondade toed" Von Krahli Teatris, lavastaja Rainer Sarnet

Eestlased muugivad da Vinci koodi / Mart Zirnask

Index Scriptorium Estoniae

Zirnask, Mart

2009-01-01

Itaalia kunstiajaloolane Nicola Barbatelli leidis tuttava kunstikogu korrastades Leonardo da Vinci arvatava autoportree. Tallinna Ülikooli maaliosakonna juhataja Orest Kormašov voolis maali järgi skulptuuri, et pilti võrrelda Leonardo õpilase Francesco Melzi tööga. Graafiline disainer Helen Kokk modelleeris arvutil maalist kolmedimensioonilise mudeli

Estrogen Receptor Mutants/Variants in Human Breast Cancer.

Science.gov (United States)

1997-12-01

a recipient of a USAMRMC Postdoctoral Fellowship Award. The authors thank Caroline Cumins -Leygue and Helen Bergen for labora- tory assistance with...of their ER status as determined by ligand binding assay. It should be stressed that an additional band can be observed in most of the samples. This

A Poetics of Graphic Design?

Science.gov (United States)

Baker, Steve

1994-01-01

Proposes that the work of the French feminist writers Helene Cixous and Luce Irigaray could serve as the basis for devising a more imaginative form of critical writing that might help to draw the history and practice of graphic design into a closer and more purposeful relation. (SR)

77 FR 75622 - Intent To Prepare a Draft Supplemental Environmental Impact Statement for Development of a Long...

Science.gov (United States)

2012-12-21

... Supplemental Environmental Impact Statement for Development of a Long-Term Sediment Management Plan of the... authorized work is described in the October 1985 report of the Chief of Engineers titled, Mount St. Helens... open construction project that was authorized in August 1985. The State of Washington is the non...

Parimad noored lauljad on selgunud. Laval särasid noored lauljad / Ülle Jantson

Index Scriptorium Estoniae

Jantson, Ülle

2007-01-01

Pärnu linna ja maakonna noorte solistide konkursist "Sügisulg" (produtsendiks Helen Erastus), mille võitjad esindavad Pärnumaad üle-eestilisel laulukonkursil "Laulukarussell 2008". Finaalkontsertidest 10.-19aastastele 23. nov. Pärnu kontserdimajas ja 3-9aastastele 25. nov. Endla teatri Küünis, nimekiri võitjatest

IV rahvusvaheline turismikonverents "Ma armastan Eestimaad!"

Index Scriptorium Estoniae

2009-01-01

25. septembril Meriton Conference&Spa Hotellis toimunud turismikonverentsist Lühiülevaade Juhan Partsi, Maria Alajõe, Paul Flattersi, Gerald Broddelezi, Raul Rebase, Raivo Vare, Birgit Prikki, Mikko Fritze, Andres Toode, Merle Adamsi ja Helen Mahmastoli ettekannetest, konverentsi moderaator oli Eesti Kaubandus- ja Tööstuskoja peadirektor Siim Raie

Kuldlõvi võitis üllatusena Hiina film tammi ehitamisest / A. L.

Index Scriptorium Estoniae

A. L.

2006-01-01

Veneetsia filmifestivali parima filmi peaauhind Kuldlõvi läks Hiina režissööri Jia Zhang-Ke filmile "Vaikelu" ("Dong"). Parima näitleja Coppa Volpi said Helen Mirren ja Ben Affleck, elutööauhinna sai režissöör David Lynch

Review Symposium.

Science.gov (United States)

Fink, Dean; Harris, Alma; Strain, Michael; Willmott, Rob; Gunter, Helen

2002-01-01

The book "Leaders and Leadership in Education," by Helen Gunter, is the topic of four separate reviews and a response by the author. Each brief essay contains references. Dean Fink describes the book as "a breathtaking survey of contemporary management and leadership literature, particularly British." (Contains 68 references.) (MLF)

78 FR 21151 - Boise White Paper, LLC, A Subsidiary of Boise Paper Holdings, LLC, Including On-Site Leased...

Science.gov (United States)

2013-04-09

... Paper, LLC, A Subsidiary of Boise Paper Holdings, LLC, Including On-Site Leased Workers From Guardsmark.... Helens, OR; Boise White Paper, LLC, A Subsidiary of Boise Paper Holdings, LLC, Vancouver, WA; Amended... workers and former workers of Boise White Paper, LLC, a subsidiary of Boise Paper Holdings, LLC, St...

Thermal phenotypic plasticity of body size in Drosophila ...

Indian Academy of Sciences (India)

... body size in Drosophila melanogaster: sexual dimorphism and genetic correlations. Jean R. David, Amir Yassin, Jean-Claude Moreteau, Helene Legout and Brigitte Moreteau. J. Genet. 90, 295–302. Table 1. Correlations between wing and thorax length at the within (n = 420) and between line level (n = 30). Temperature.

"Middletown" as a Model for Community Studies (With Comparative Data from Erie, Pennsylvania).

Science.gov (United States)

Frank, Carl M.

1985-01-01

In 1920 Robert S. and Helen M. Lynd published the results of their exhaustive study of everyday life in Muncie, Indiana, dubbing the city "Middletown" as a symbol of the typical American community. Salient conclusions of the study are summarized, and significant recent literature on Middletown is assessed. (RM)

Kumus näeb maailmamuutjaid / Helen Teesalu

Index Scriptorium Estoniae

Teesalu, Helen

2008-01-01

Maailmamuutjate filmifestival näitab neljal järjestikusel kolmapäeval dokfilme eriliste inimeste erilistest ettevõtmistest. Täna on Kumus Chema Rodrigueze "Raudtee tähed", mida kommenteerivad Eda Mölder ja Artur Taevere

Ooperisse lipsu ja õhtukleidiga kohvris / Helen Ennok

Index Scriptorium Estoniae

Ennok, Helen

2014-01-01

Artikkel tutvustab lühidalt Euroopa ooperimaju: Viini Riigiooper, Milano La Scala, Pariisi Rahvusooper, Berliini Riigiooper, Royal Opera House, Rootsi Kuninglik Ooper, Taani kuninglik ooper, Brüsseli La Monnaie ooper, Helsingi Ooperimaja, Läti Rahvusooper

Marie N seisis pea peal / Helen Urbanik

Index Scriptorium Estoniae

Urbanik, Helen

2002-01-01

Tänavuse Eurovisiooni võitjast Marija Naumovast, tema heliplaatidest "Do svetlõh sljoz" ("Magusate pisarateni"), "Leskaties acis" ("Vaata mu silmadesse"), "Ma voix, ma vie" ("Minu hääl, minu tee")

Iisraeli innovatsioonipõhine majandusmudel eeskujuks / Helen Popp

Index Scriptorium Estoniae

Popp, Helen

2011-01-01

Iisrael on oma majandustegevuse planeerimisel keskendunud innovatsioonile ja start-up-firmadele, Iisrael on maailma üks suuremaid teadus- ja arendustegevusse investeerijaid. Eesti teadus- ja arenduskeskused, innovatsioonile suunatud ettevõtted ja ka teaduspargid võiksid koostööpartnerite otsingul suunata pilgu teiste hulgas ka Iisraeli poole

Kivisõõrid tuulisel saarel / Helen Arusoo

Index Scriptorium Estoniae

Arusoo, Helen, 1972-

2013-01-01

Eesti, Läti ja Rootsi looduslikke pühapaiku kaardistanud projekti Cult Identity, mille Eesti poolne partner oli Hiite Maja, käigus valmis kodulehelt www.ancientsites.eu ning toimus õppereis ajakirjanikele nende riikide pühapaikadesse. Pikemalt Rootsis Kuggörarna saarel ja ka mujal Rootsi rannikul asuvast kividest laotud labürintidest

Helen Mirren krooniti Veneetsias kuningannaks / Triin Tael

Index Scriptorium Estoniae

Tael, Triin

2006-01-01

Näitleja võitis parima naisnäitleja auhinna Elizabet II rolliga Stephen Frears'i filmis "Kuninganna" ("The Queen"). Parima filmi peaauhind Kuldlõvi läks Hiina režissööri Jia Zhang-Ke filmile "Vaikelu" ("Dong"). Ka teistest Veneetsia 63. filmifestivali võitjatest

Naised, keda mehed rajal kardavad / Helen Teesalu

Index Scriptorium Estoniae

Teesalu, Helen

2008-01-01

Vt. ka Postimees : na russkom jazõke : Avto i Tehnika 26. sept., lk. 4. CCG ehk Car Club Girls on Eesti ainuke ametlik naiste autoklubi, mille liikmed teevad võidusõidu- ja kiirendusrajal silmad ette nii mõnelegi mehele

Helen Mendes | IDRC - International Development Research Centre

International Development Research Centre (IDRC) Digital Library (Canada)

I think my health-related stories have made the greatest impact. ... find stories about local research, which has a greater impact on the lives of people here. ... Understanding the algorithms that rule news distribution on social media also helps.

Kosmosekostüümid ulmefilmides / Helen Valk

Index Scriptorium Estoniae

Valk, Helen

2011-01-01

Lõputöös uuritakse ulmefilmide kostüümides esinevaid korrapärasusi ja reegleid ning seoseid reaalsuse ja ulme vahel, samuti ulme ilminguid tänapäeva moes. Praktilise tööna valmis prêt-á-porter moekollektsioon "Nebula"

Pre-eruptive conditions of the ~31 ka rhyolitic magma of Tlaloc volcano, Sierra Nevada Volcanic Range, Central Mexico

Science.gov (United States)

Macias, J.; Arce, J.; Rueda, H.; Gardner, J.

2008-12-01

Tlaloc volcano is located at the northern tip of the Sierra Nevada Volcanic Range in Central Mexico. This Pleistocene to Recent volcanic range consists from north to south of Tlaloc-Telapón-Teyotl-Iztaccíhuatl-and- Popocatépetl volcanoes. While andesitic to barely dacitic volcanism dominates the southern part of the range (i.e. Popocatépetl and Iztaccíhuatl); dacitic and rare rhyolithic volcanism (i.e. Telapón, Tlaloc) dominates the northern end. The known locus of rhyolitic magmatism took place at Tlaloc volcano with a Plinian-Subplinian eruption that occurred 31 ka ago. The eruption emplaced the so-called multilayered fallout and pumiceous pyroclastic flows (~2 km3 DRE). The deposit consists of 95% vol. of juvenile particles (pumice + crystals) and minor altered lithics 5% vol. The mineral association of the pumice fragments (74-76 % wt. SiO2) consists of quartz + plagioclase + sanidine + biotite and rare oxides set in a glassy groundmass with voids. Melt inclusions in quartz phenocrysts suggest that prior to the eruption the rhyolitic contain ~7% of H2O and Nevado de Toluca volcano (~6 km) some 50 km to the southwest.

Death Education for the Health Professional.

Science.gov (United States)

Benoliel, Jeanne Quint, Ed.

The perspectives of a number of health professionals based on their experiences in providing death education courses are presented in essays. In "Interdisciplinary Death Education in a Nursing School" (Helen L. Swain and Kathleen V. Cowles), the development of an undergraduate elective course in death, dying, and bereavement at the…

Metaphor and the Rhetorical Invention of Cold War "Idealists."

Science.gov (United States)

Ivie, Robert L.

1987-01-01

Presents a procedure for identifying metaphorical concepts guiding the rhetorical invention of three Cold War "idealists": Henry Wallace, J. William Fulbright, and Helen Caldicott, whose collective failure to dispel threatening images of the Soviets is located in a recurrent system of metaphors that promotes a reversal of the enemy-image…

Journal for Language Teaching - Vol 39, No 2 (2005)

African Journals Online (AJOL)

Phonological awareness and the minimising of reading problems: a South African perspective · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Anna J Hugo, SG le Roux, Helene Muller, Norma Nel, 210-225. http://dx.doi.org/10.4314/jlt.v39i2.6058 ...

Kitsas silmaring on nuhtluseks endale, teistele, kogu riigile / Raivo Juurak, Kaiko Lippur

Index Scriptorium Estoniae

Juurak, Raivo, 1949-

2014-01-01

Westholmi Gümnaasiumi riigikaitseõpetuse õppetooli juhataja Kaiko Lippur selgitab, et riigikaitseõpetus on eelkõige õpilaste silmaringi laiendamiseks. Küsimusele, mida riigikaitseõpetus annab, vastavad Westholmi gümnaasiumi õpilased Jaan Kaarel Sepp, Marie Helen Lisete Kikas ja Kaisa-Mai Kallaste ning Rocca al Mare kooli lapsevanem Katariina L. Martens

Shame: The Emotional Basis of Library Anxiety

Science.gov (United States)

McAfee, Erin L.

2018-01-01

In 1986, Constance Mellon found that 75 to 85 percent of undergraduate students experienced library anxiety as well as shame about their anxiety. Fifteen years earlier, Helen Block Lewis began her groundbreaking research in shame theory. This paper explores the affective components of library anxiety using the pioneering research of Constance…

Prof dr Pasquale Pistone soovitab direktiive vahetult kohaldada / Pasquale Pistone ; interv. Erki Uustalu

Index Scriptorium Estoniae

Pistone, Pasquale

2005-01-01

Intervjuu Salerno Ülikooli teaduskonna dotsendiga, kes õpetas Eesti ametnikele Euroopa Kohtu pretsedendiõigust otseste maksude valdkonnas. Lisatud kommentaarid: Reimer, Ekkehart. Euroopa maksutaeva tõusev täht ; Uustalu, Erki. Särav isiksus, suurepärane suhtleja ; Pahapill Helen. Väljapaistev õigusteadlane ja hinnatud õppejõud. Lisatud ka Pasquale Pristone elulugu

Concluding Remarks | Ewing | Rwanda Journal

African Journals Online (AJOL)

Rwanda Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 2, No 2 (2015) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Concluding Remarks. Helen Ewing. Abstract. No Abstract. Full Text:.

A Comparison of HAART Outcomes between the US Military HIV Natural History Study (NHS) and HIV Atlanta Veterans Affairs Cohort Study (HAVACS)

Science.gov (United States)

2013-05-01

Acknowledgments The IDCRP HIV Working Group includes: Susan Banks, RN, CAPT Mary Bavaro, MD, Ionut Bebu, PhD, Helen Chun, MD, Nancy Crum- Cianflone, MD, MPH...Cathy Decker, MD, Conner Eggleston, LTC Tomas Ferguson, MD, COL Susan Fraser, MD, MAJ Joshua Hartzell, MD, MAJ Joshua Hawley, MD, LTC Gunther Hsue, MD

From neurotic guilt to existential guilt as grief: the road to interiority, agency, and compassion through mourning. Part II.

Science.gov (United States)

Kavaler-Adler, Susan

2006-12-01

This study is a continuation of an article that was published in the previous issue of The American Journal of Psychoanalysis (Volume 66, Number 3, September 2006). The case of Helen is illustrated in terms of the analysand's developmental mourning, countertransference, interiority, antilibidinal ego, and transformation of aggression into self-agency.

Fear of crime: The role of sex, neuroticism and prior victimization of ...

African Journals Online (AJOL)

Fear of crime: The role of sex, neuroticism and prior victimization of Ibadan, Nigeria. Helen O Osinowo. Abstract. No Abstract Available African Journal for the Psychological Study of Social Issues Vol.4(2) 1999: 275-285. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Kultuuripealinn kutsub sel nädalal tundmatuid katuseid käima / Heidi Kukk

Index Scriptorium Estoniae

Kukk, Heidi

2010-01-01

Tallinn 2011 ootussarja "52 üllatust ja ideed" raames 12. ja 13. augustil toimuvast projektist "Katustele", mille eestvedajateks on Eesti Kunstiakadeemia üliõpilased Helen Melesk ja Hello Upan. Järgmisena on kavas tantsu- ja laululine performance Anneli Leinbergi juhendamisel ja Tallinna merepiiri kasutule olekule pühendatud kunstiprojekt "Bassein"

Veneetsias võitis Hiina üllataja

Index Scriptorium Estoniae

2006-01-01

Veneetsia filmifestivali parima filmi peaauhind Kuldlõvi läks Hiina režissööri Jia Zhang-Ke filmile "Vaikelu" ("Dong"). Hõbelõvi said Alain Resnais' "Isiklikud hirmud avalikes kohtades" ("Coeurs") ja Emanuele Crialese "Kuldne uks" ("Nuodomondo"). Parima näitleja Coppa Volpi said Helen Mirren ja Ben Affleck

"Sügisulg" toob noored anded suurele lavale / Silja Joon

Index Scriptorium Estoniae

Joon, Silja, 1966-

2007-01-01

Pärnu linna ja maakonna noorte solistide konkursist "Sügisulg" (produtsendiks Helen Erastus), mille võitjad esindavad Pärnumaad üle-eestilisel laulukonkursil "Laulukarussell 2008" (finaalkontserdid 10.-19aastastele 23. nov. Pärnu kontserdimajas ja 3-9aastastele 25. nov. Endla teatri Küünis, finalistid vt. www.parnukontsert.ee)

75 FR 32778 - Change in Bank Control Notices; Acquisition of Shares of Bank or Bank Holding Companies

Science.gov (United States)

2010-06-09

... June 23, 2010. A. Federal Reserve Bank of Chicago (Colette A. Fried, Assistant Vice President) 230 South LaSalle Street, Chicago, Illinois 60690-1414: 1. John V. Tippmann, Sr., as an individual, and John V. Tippman, Sr.; John and Helen McCarthy; Richard and Sally Ley; John Tippman, Jr.; Patrick Tippman...

75 FR 38097 - Change in Bank Control Notices; Acquisition of Shares of Bank or Bank Holding Companies

Science.gov (United States)

2010-07-01

..., 2010. A. Federal Reserve Bank of Chicago (Colette A. Fried, Assistant Vice President) 230 South LaSalle Street, Chicago, Illinois 60690-1414: 1. John V. Tippmann, Sr., as an individual; John V. Tippmann, Sr.; John and Helen McCarthy; Richard and Sally Ley; John Tippmann, Jr.; Patrick Tippmann; and Brian and...

Novõi utshebnõi god budjet Godom dizaina / Ksenia Repson

Index Scriptorium Estoniae

Repson, Ksenia

2006-01-01

Eesti Kunstiakadeemia disainihariduse 40. aastapäeva tähistava Disainiaasta üritusi: rahvusvaheline disainikonverents Connecting, näitus "40 aastat disaini" Tarbekunsti- ja Disainimuuseumis, disainikonkurss, rändnäitused, seminarid, Tallinna disainikaart (koostab Kai Lobjakas, joonistavad Indrek Sirkel ja Mikk Heinsoo). Projekti "Disainiaasta" juht on Ruth Helene Melioranski

Tallinna ülikool ehitab uue Ursa maja / Mihkel Tamm

Index Scriptorium Estoniae

Tamm, Mihkel

2017-01-01

2018. a. veebruaris kavatseb Tallinna Ülikool hakata lammutama loodus- ja terviseteaduste õppehoonet ehk Ursa maja. Amortiseerunud hoone asemele ehitatakse uus, mille uksed loodetakse tudengitele avada 2019. aasta sügissemestriks. Selgitusi uue hoone kahta jagab TLÜ kantsler Peep Jonas ning kavandatava õueala kohta keskkonnakorralduse professor Helen Sooväli-Sepping

Browse Title Index

African Journals Online (AJOL)

Items 101 - 150 of 699 ... ... Bioassessment of the ecological integrity of river ecosystems using aquatic macroinvertebrates: an overview with a focus on South Africa, Abstract. Dean J Ollis, Helen F Dallas, Karen J Esler, Charles Boucher. Vol 40, No 1 (2015), Biochemical and haematological responses in African catfish Clarias ...

Achieving Equity in Higher Education: The Unfinished Agenda

Science.gov (United States)

Astin, Alexander W.; Astin, Helen S.

2015-01-01

In this retrospective account of their scholarly work over the past 45 years, Alexander and Helen Astin show how the struggle to achieve greater equity in American higher education is intimately connected to issues of character development, leadership, civic responsibility, and spirituality. While shedding some light on a variety of questions…

Meeli Kõiva vitraažid ajakirja Stained Glass talvenumbris / Rein Eriksson

Index Scriptorium Estoniae

Eriksson, Rein

1998-01-01

Intervjuust Meeli Kõivaga Ameerika Ühendriikide vitraažikunstnike Assotsiatsiooni ajakirja "Stained Glass" talvenumbris. Avaldati 8 fotot kunstniku vitraažidest. Artikli "Unistused transparentsest ruumist" autor - USA vitraažikunstnike Assotsiatsiooni endine president Helene Weiss. M. Kõiva esines aprillis 1997 akvarellidega grupinäitusel New Yorgis, Broadway galeriis Art 54.

Self Esteem, locus of control, self-efficacy and neuroticism as ...

African Journals Online (AJOL)

Self Esteem, locus of control, self-efficacy and neuroticism as correlates of job satisfaction among secondary school teachers in Nigeria. Helen O Nwagwu, SO Salami. Abstract. No Abstract Available African Journal for the Psychological Study of Social Issues Vol.4(1) 1999: 48-61. Full Text: EMAIL FULL TEXT EMAIL FULL ...

Mikroskopische Studien ueber Gesteine aus den Molukken. 1. Gesteine von Ambon und den Uliassern. Mit einem französischen Résumé

NARCIS (Netherlands)

Schroeder van der Kolk, J.L.C.

1888-01-01

Dans le traité précédent j’ai décrit les types les plus caractéristiques parmi les échantillons de roche recueillis par M. MARTIN pendant ses voyages dans les Moluques. Ainsi il s’agit des Granites à biotite, des Péridotites, des Dacites, des Andésites à pyroxène, des Brèches volcaniques et aussi

Silicic magma generation at Askja volcano, Iceland

Science.gov (United States)

Sigmarsson, O.

2009-04-01

Rate of magma differentiation is an important parameter for hazard assessment at active volcanoes. However, estimates of these rates depend on proper understanding of the underlying magmatic processes and magma generation. Differences in isotope ratios of O, Th and B between silicic and in contemporaneous basaltic magmas have been used to emphasize their origin by partial melting of hydrothermally altered metabasaltic crust in the rift-zones favoured by a strong geothermal gradient. An alternative model for the origin of silicic magmas in the Iceland has been proposed based on U-series results. Young mantle-derived mafic protolith is thought to be metasomatized and partially melted to form the silicic end-member. However, this model underestimates the compositional variations of the hydrothermally-altered basaltic crust. New data on U-Th disequilibria and O-isotopes in basalts and dacites from Askja volcano reveal a strong correlation between (230Th/232Th) and delta 18O. The 1875 AD dacite has the lowest Th- and O isotope ratios (0.94 and -0.24 per mille, respectively) whereas tephra of evolved basaltic composition, erupted 2 months earlier, has significantly higher values (1.03 and 2.8 per mille, respectively). Highest values are observed in the most recent basalts (erupted in 1920 and 1961) inside the Askja caldera complex and out on the associated fissure swarm (Sveinagja basalt). This correlation also holds for older magma such as an early Holocene dacites, which eruption may have been provoked by rapid glacier thinning. Silicic magmas at Askja volcano thus bear geochemical signatures that are best explained by partial melting of extensively hydrothermally altered crust and that the silicic magma source has remained constant during the Holocene at least. Once these silicic magmas are formed they appear to erupt rapidly rather than mixing and mingling with the incoming basalt heat-source that explains lack of icelandites and the bi-modal volcanism at Askja

Tectonic evolution of the central-eastern sector of Trans Mexican Volcanic Belt and its influence on the eruptive history of the Nevado de Toluca volcano (Mexico)

Science.gov (United States)

Bellotti, F.; Capra, L.; Groppelli, G.; Norini, G.

2006-11-01

The Nevado de Toluca is an andesitic to dacitic stratovolcano of Late Pliocene-Holocene age located within the central and eastern sectors of the Trans Mexican Volcanic Belt. Morphostructural analysis, aerial photograph and satellite image interpretation, structural analysis and geological fieldwork were methods used to investigate the relationship between the evolution of the volcano and the tectonic framework of its basement. The study revealed that the area of Nevado de Toluca is affected by three main fault systems that intersect close to the volcanic edifice. These are from oldest to youngest, the Taxco-Querétaro, San Antonio and Tenango fault systems. The NNW-SSE Taxco-Querétaro fault system was active in the area since Early Miocene, and is characterized by right-lateral transtensive movement. Its reactivation during Early to Middle Pleistocene was responsible for the emplacement of andesitic to dacitic lava flows and domes of La Cieneguilla Supersynthem. The NE-SW San Antonio fault system was active during Late Pliocene, before the reactivation of the Taxco-Querétaro fault system, and is characterized by extensional left-lateral oblique-slip kinematics. The youngest is the E-W Tenango fault system that has been active since Late Pleistocene. This fault system is characterized by transtensive left-lateral strike-slip movement, and partly coeval with the youngest eruptive phase, the Nevado Supersynthem, which formed the present summit cone of the Nevado de Toluca volcano. The stress re-orientation from the Taxco-Querétaro to the Tenango fault system during Late Pleistocene is responsible for the ˜ 1 Ma hiatus in the magmatic activity between 1.15 Ma and 42 ka. After this period of repose, the eruptive style drastically changed from effusive to explosive with the emission of dacitic products. The methodology presented here furnish new data that can be used to better assess the complex structural evolution of this sector of the Trans Mexican Volcanic Belt

The timing of compositionally-zoned magma reservoirs and mafic 'priming' weeks before the 1912 Novarupta-Katmai rhyolite eruption

Science.gov (United States)

Singer, Brad S.; Costa, Fidel; Herrin, Jason S.; Hildreth, Wes; Fierstein, Judith

2016-01-01

The June 6, 1912 eruption of more than 13 km3 of dense rock equivalent (DRE) magma at Novarupta vent, Alaska was the largest of the 20th century. It ejected >7 km3 of rhyolite, ~1.3 km3 of andesite and ~4.6 km3 of dacite. Early ideas about the origin of pyroclastic flows and magmatic differentiation (e.g., compositional zonation of reservoirs) were shaped by this eruption. Despite being well studied, the timing of events that led to the chemically and mineralogically zoned magma reservoir remain poorly known. Here we provide new insights using the textures and chemical compositions of plagioclase and orthopyroxene crystals and by reevaluating previous U-Th isotope data. Compositional zoning of the magma reservoir likely developed a few thousand years before the eruption by several additions of mafic magma below an extant silicic reservoir. Melt compositions calculated from Sr contents in plagioclase fill the compositional gap between 68 and 76% SiO2 in whole pumice clasts, consistent with uninterrupted crystal growth from a continuum of liquids. Thus, our findings support a general model in which large volumes of crystal-poor rhyolite are related to intermediate magmas through gradual separation of melt from crystal-rich mush. The rhyolite is incubated by, but not mixed with, episodic recharge pulses of mafic magma that interact thermochemically with the mush and intermediate magmas. Hot, Mg-, Ca-, and Al-rich mafic magma intruded into, and mixed with, deeper parts of the reservoir (andesite and dacite) multiple times. Modeling the relaxation of the Fe-Mg concentrations in orthopyroxene and Mg in plagioclase rims indicates that the final recharge event occurred just weeks prior to the eruption. Rapid addition of mass, volatiles, and heat from the recharge magma, perhaps aided by partial melting of cumulate mush below the andesite and dacite, pressurized the reservoir and likely propelled a ~10 km lateral dike that allowed the overlying rhyolite to reach the surface.

Teacher Labor Markets in Developed Countries

Science.gov (United States)

Ladd, Helen F.

2007-01-01

Helen Ladd takes a comparative look at policies that the world's industrialized countries are using to assure a supply of high-quality teachers. Her survey puts U.S. educational policies and practices into international perspective. Ladd begins by examining teacher salaries--an obvious, but costly, policy tool. She finds, perhaps surprisingly,…

76 FR 81940 - Change in Bank Control Notices; Acquisitions of Shares of a Bank or Bank Holding Company

Science.gov (United States)

2011-12-29

... Holding Company The notificants listed below have applied under the Change in Bank Control Act (12 U.S.C... bank holding company. The factors that are considered in acting on the notices are set forth in... South LaSalle Street, Chicago, Illinois 60690-1414: 1. Helen P. Johnson-Leipold, Imogene P. Johnson, all...

Pöffihunt kutsub kinno

Index Scriptorium Estoniae

2010-01-01

19.11.-5.12.2010 kestva Pimedate Ööde Filmifestivali alafestivalidest. Vestlusest noorte- ja lastefilmide festivali Just Film juhi Mikk Granströmiga, tudengi- ja lühifilmide festivali Sleepwalkers juhi Helen Vinogradoviga, Nokia Mobiilifilmide festivali MOFF juhi Maria Pleesiga ning Animafilmide festivali Animated Dreams tegevjuhi Mark Kuslapuu ja programmijuhi Heilika Pikkoviga

Product modelling: '20 years of stalemate'?

DEFF Research Database (Denmark)

Galle, Per

1998-01-01

In a recent special issue of Design Studies Michael Ramscar, John Lee, and Helen Pain level a severe criticism against a field of research known as product modeling; a criticism that would be rather damaging if it were based on cogent arguments. I shall argue in this paper that it is not....

South African Medical Journal - Vol 90, No 3 (2000)

African Journals Online (AJOL)

Randomised controlled trial of the efficacy of misoprostol used as a cervical ripening agent prior to termination of pregnancy in the first trimester · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Eric T M de Jonge, Rachel Jewkes, Jonathan Levin, Helen Rees, 256-261 ...

Kei hea te Ora? The Whereabouts of the Health of Children in the Early Childhood Curriculum of Aotearoa New Zealand

Science.gov (United States)

Gibbons, Andrew

2015-01-01

The policies and practices of early childhood teaching in Aotearoa New Zealand have been an ongoing site of political, economic, social and cultural contestation. Competing values and beliefs regarding experiences of both the child and the teacher have been central to the contesting. Helen May (2001, 2009) tracks these tensions through the waxing…

Elizabeth II / Fagira D. Morti

Index Scriptorium Estoniae

Fagira D. Morti, pseud., 1974-

2006-01-01

Järjejutt Elizabeth II elust. Järgneb nr. 80, lk. 30-33, nr. 81, lk. 30-32, nr. 82, lk. 34-36, nr. 83, lk. 34-37, nr. 84, lk. 42-45, nr. 85, lk. 36-38, 86, lk. 44-47, nr. 87, lk. 32-35. Nr. 86 ja 87 autor: Helene Wait

Pärnumaa "Kultuuripärl" on Bruno Sõmeri / Silja Joon

Index Scriptorium Estoniae

Joon, Silja, 1966-

2006-01-01

28. dets. Pärnu kontserdimajas toimunud Pärnumaa kultuuri- ja sporditegijate aastalõpu galaõhtul "Tähesära 2006" pälvisid teisete seas preemiad ka lauluõpetaja Anne Uusna, laulukonkursi "Sügisulg" korraldaja Helen Erastus, koorijuht Toomas Voll, rahvatantsurühma Kajakas juht Rita Mändla ja kunstnik Toomas Kuusing

Kõrgharidusprogramm Erasmus : [2011

Index Scriptorium Estoniae

2012-01-01

Eesti kõrgkoolide üliõpilaste õpirändest Erasmus programmi raames. Euroopa Komisjon kuulutas 2011. a. märtsis välja Erasmuse programmi 25. aastapäeva riiklike saadikute konkursi 2012. aastaks. Eestist valiti saadikuteks Tallinna Ülikooli üliõpilane Helen Margus ja Tallinna Ülikooli õppejõud Sirje Virkus

Acute mental health care according to recent mental health ...

African Journals Online (AJOL)

Objective: This is the third of three reports on the follow-up review of mental health care at Helen Joseph Hospital (HJH). The study reviewed existing South African standards for mental health care facilities. Architectural principles and implications for the use of space were deducted from recent legislation. Objectives were to ...

Tartu Ülikooli Narva Kolledž = University of Tartu Narva College / Hannes Praks

Index Scriptorium Estoniae

Praks, Hannes, 1973-

2013-01-01

Eesti Sisearhitektide Liidu 2012. aasta parima avaliku ruumi preemia pälvinud TÜ Narva Kolledzi sisekujundusest. Autorid: Hannes Praks, Kadri Tamme, Kristjan Holm, Liisi Murula, Toomas Pääsuke, Ahti Grüngerg, Daniel Marius Reisser, Helen Sarapuu. Arhitektuur: Kavakava. ESLi aastapreemiate žürii liikmete Raivo Puusepa ja Mari Kurismaa arvamused

Kolmanda raamatu kiituseks / Peeter Olesk

Index Scriptorium Estoniae

Olesk, Peeter, 1953-

2009-01-01

Tutvustus: Isaacson, Walter. Einstein : tema elu ja universum / tõlkinud Matti Piirimaa. Tallinn : Eesti Raamat, 2009; Fortey, Jacqueline. Kuulsad teadlased (Silmaring) / tõlkinud Ülle Haav ja Helen Haav. Tallinn : Koolibri, 2009; Vaim ja aeg (Lehed ja tähed : looduse ja teaduse aastaraamat, 5) / koostanud Indrek Rohtmets ja Toomas Kukk. Tallinn : Loodusajakiri, 2009

Anne Veesaar astus Valgas üles uudses rollis / Jaan Rapp

Index Scriptorium Estoniae

Rapp, Jaan

2010-01-01

2010. aasta iga kuu viimasel reedel esitab näitlejanna Anne Veesaar Raadio Ruudus katkendeid Valgamaa kirjanike loomingust. 14. jaanuaril kohtumisel lugejatega rääkis Valgas sündinud näitlejanna oma elulooraamatust "Anne Veesaar : elus, see on kõige tähtsam", mille on kirja pannud Helen Eelrand, ja oma praegustest tegemistest

Kaubamaja "Lemon" - Arco Ärikeskus : Estonia pst. 1, Tallinn

Index Scriptorium Estoniae

2002-01-01

1958. a. valminud hoone rekonstrueerimine. Projekteerija: EA Reng. Arhitekt Martin Aunin. Ehituskonstruktsioonid: Riho Märtson. Insenertehnilised osad: Karmo Pajo, Maarika Kurvits, Eha Treial. Valgusinstallatsioon: Meeli Kõiva. Kaupluste mööbel, kohtvalgustus: Priit Põldme, Ants Tolli, Ruth-Helene Kaasik, Hugo Mitt, Mart Vesker, Tarmo Piirmets. Projekt 2001, valmis 2002. I korruse põhiplaan, 4 vaadet

A Comparative Analysis of Educational Teaching in Shahnameh and Iliad

Science.gov (United States)

Shahverdi, Elham; Sepahvandi, Masood

2018-01-01

Ferdowsi's Shahnameh and Homer's Iliad are among the first literary masterpieces of Iran and Greece. These teachings include the educational teachings of Zal and Roudabeh, and Paris and Helen. This paper presents a comparative look at the immortal effect of this Iranian poet with Homer's poem--the Greek blind poet. In this comparison, using a…

Integrating Social Science and Ecosystem Management: A National Challenge

Science.gov (United States)

Cordell; H. Ken; Linda Caldwell

1995-01-01

These proceedings contain the contributed papers and panel presentations, as well as a paper presented at the National Workshop, of the Conference on Integrating Social Sciences and Ecosystem Management, which was held at Unicoi Lodge and Conference Center, Helen, GA, December 12-14, 1995. The overall purpose of this Conference was to improve understanding, integration...

The Makah Whale Hunt: A Social Studies Symposium in the Classroom

Science.gov (United States)

Bornstein-Grove, Matthew; Hamel, Fred L.

2013-01-01

The conversation starts quickly as two students come together in a 10th grade social studies classroom, half-way through a role play activity a symposium begins. Both students are sporting "Hello, my name is…" stickers on their shirts, and each attempts to speak in character. One represents an anti-whaling activist. Helen stands holding…

Noore õpetaja stardiraha tekitab kultuurikomisjonis vaidlusi / Kai Kalamees

Index Scriptorium Estoniae

Kalamees, Kai

2007-01-01

24. oktoobril esimese lugemise läbinud eelnõu, mis tagab 2008. aasta 1. septembrist esimest korda koolis tööd alustavatele õpetajatele stardiraha, jõuab uuesti riigikogu ette detsembris. Tallinna Ülikoolis kolmandal kursusel klassiõpetajaks õppiv Helen Tuga seob oma tuleviku õpetajatööga ka ilma riigi antava 200 000 kroonita

Acute mental health care according to recent mental health ...

African Journals Online (AJOL)

Objective: This is the second of three reports on the follow-up review of mental health care at Helen Joseph Hospital (HJH). Objectives for the review were to provide realistic estimates of cost for unit activities and to establish a quality assurance cycle that may facilitate cost centre management. Method: The study described ...

College and University Governance: The University of Virginia Governing Board's Attempt to Remove the President

Science.gov (United States)

American Association of University Professors, 2013

2013-01-01

The report documents a major breakdown in governance at UVA, focusing on the role of the board of visitors and its rector, Helen Dragas, who initiated the effort to force the president's resignation. It finds that the events at the university resulted from "a failure by those charged with institutional oversight to understand the institution…

Viewing Volcanoes

Science.gov (United States)

Wighting, Mervyn J.

2005-01-01

When Mount St. Helens threatened to erupt again in 2004, it grabbed headlines and captured the imagination of the country. Science classrooms nationwide used the event as an opportunity to make real-world connections to Earth science concepts introduced in the classroom. Thanks to modern technology, teachers no longer have to wait for the next…

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Further, Hudhud and Helen, is compared to a deep depression formed over Bay of Bengal to highlight the significance of the mid-level vortex in the genesis of a tropical cyclone. Major results obtained are as follows: stronger positive PV anomalies are noticed over upper and lower levels of troposphere near the storm center ...

Development and validation of a new fallout transport method using variable spectral winds

International Nuclear Information System (INIS)

Hopkins, A.T.

1984-01-01

A new method was developed to incorporate variable winds into fallout transport calculations. The method uses spectral coefficients derived by the National Meteorological Center. Wind vector components are computed with the coefficients along the trajectories of falling particles. Spectral winds are used in the two-step method to compute dose rate on the ground, downwind of a nuclear cloud. First, the hotline is located by computing trajectories of particles from an initial, stabilized cloud, through spectral winds to the ground. The connection of particle landing points is the hotline. Second, dose rate on and around the hotline is computed by analytically smearing the falling cloud's activity along the ground. The feasibility of using spectral winds for fallout particle transport was validated by computing Mount St. Helens ashfall locations and comparing calculations to fallout data. In addition, an ashfall equation was derived for computing volcanic ash mass/area on the ground. Ashfall data and the ashfall equation were used to back-calculate an aggregated particle size distribution for the Mount St. Helens eruption cloud

Alternative Tsunami Models

Science.gov (United States)

Tan, A.; Lyatskaya, I.

2009-01-01

The interesting papers by Margaritondo (2005 "Eur. J. Phys." 26 401) and by Helene and Yamashita (2006 "Eur. J. Phys." 27 855) analysed the great Indian Ocean tsunami of 2004 using a simple one-dimensional canal wave model, which was appropriate for undergraduate students in physics and related fields of discipline. In this paper, two additional,…

Perspective and Doing Good Work

Directory of Open Access Journals (Sweden)

Brett Bonfield

2012-01-01

Full Text Available This post is adapted from a speech I gave at Drexel University’s Beta Phi Mu initiation on December 6, 2011. The text of the original is available on Scribd, and a video of my speech, which includes a brief introduction by Helen Snowden is available on Vimeo. Greek Picnic is a reunion and gathering of [...

Hämmastavad esikteosed / Aita Kivi

Index Scriptorium Estoniae

Kivi, Aita, 1954-

2002-01-01

Sisu : Andrew Miller. Salakaval valu; Helen Dewitt. Viimane samurai; Michel Faber. Naha all; Ana̐s Nin. Venuse delta; Eeva Park. Vaba langemine; Henri Troyat. Kohutavad keisrinnad; 11. september : terrorirünnaku tagamaad : / [koost. Stefan Aust, Cordt Schnibben... jt.]; Deepak Chopra. Täiuslik tervis; Charlie Jones. Elu on võrratu; Matt Ridley, Matt. Vooruse lätted

Sõda meie ümber / Heigo Kaldra

Index Scriptorium Estoniae

Kaldra, Heigo

2006-01-01

Rets. rmt.: Ed Michaels, Helen Handfield-Jones, Beth Axelrod. "Sõda talentide pärast". Raamat tugineb põhjalikule uurimusele, kus toodud numbrid, protsendid ja näited viitavad ühele ja samale: inimene, tema oskused, teadmised ja kogemused on ettevõtte kalleim vara, mille hoidmisele ja arendamisele tuleb juhtida kõikide juhtide põhitähelepanu

Järelehüüd sovhoosi kronule / Mats Traat

Index Scriptorium Estoniae

Traat, Mats, 1936-

2003-01-01

Sisu: Järelehüüd sovhoosi kronule ; Laul viiekümnest tiisikerist ; Ballaad Eestimaa kulakust ; Laul lüpsipiigast ; Ballaad lüürikust ja raudtee kassipojast ; Ballaad Villem Koogist ja lutikast ; Nüüdisnovelli süžee ; Avarii ; Reinvaldi teekond ; Harala elulood : Andrei Suikkunen ; Alviine Birkenbaum ; Jadwiga Purre ; Hendrik Liira ; Helen Laidmaa ; Manivald Sell ; Pauline Allikas

"Zombievõluri" võlumine / Marianne Ostrat

Index Scriptorium Estoniae

Ostrat, Marianne

2007-01-01

10. Pimedate Ööde Filmifestivali käigus tehti telefoniga Nokia N93 mobiilifilm "Zombievõlur" : stsenarist Jim Ashilevi : režissöör Birgit Demidova : operaator Christian Johannes Kask : produtsent Helen Tootsi : peaosalised Beatrice ja Bert Pringi. Filmitegijad jutustavad filmi saamisloost. Lisatud Nokia turundusjuhi Ülle Rohtla ja PÖFFi tegevjuhi Kristo Tohveri kommentaarid

Предполагаемый автопортрет Леонардо да Винчи в Эстонии

Index Scriptorium Estoniae

2010-01-01

Kadrioru Kunstimuuseumis eksponeeritakse 5.-12. veebruarini 2010 Leonardo da Vinci arvatavat autoportreed, 6. veebruaril toimub Tallinna Ülikoolis rahvusvaheline konverents "A Key to Leonardo". Lõuna-Itaalia erakogust leitud maali analüüsimisega tegelesid Tallinna Ülikooli maali ja maalitehnoloogia õppejõud Orest Kormašov, kes valmistas klassikalise portreeskulptuuri, arvutisimulatsiooni teostas Eesti Kunstiakadeemia graafilise disaini tudeng Helen Kokk

Ümar laud = A round table / Kalle Komissarov

Index Scriptorium Estoniae

Komissarov, Kalle, 1976-

2010-01-01

8. oktoobril 2009 toimunud konverentsile "Kohaliku kogukonna roll avatud ja jätkusuutliku linnaruumi kujundamisel" järgnenud ümarlauast, kuhu olid kutsutud Helen Sooväli Tallinna Ülikooli linnakorralduse osakonnast, Kerttu Märtin Tallinna Linnaplaneerimise Ametist ja arhitekt Kalle Komissarov. Elanike kaasamisest planeerimistegevusse, elukeskkonna planeerimisest kasutaja seisukohalt. Avatud linnast, kus arhitekti ja urbanisti roll on kuraatorilaadne

Nargen Opera toob vaataja ette uue eesti kammerooperi / Priit Pruul

Index Scriptorium Estoniae

Pruul, Priit

2006-01-01

20. apr. esietendub Von Krahli Teatris Peeter Jalaka lavastuses Tõnu Kõrvitsa kammerooper "Mu luiged, mu mõtted", mille aluseks on luuletaja Marie Heibergi saatus. Libreto autor on Maarja Kangro. Kammerooper tuleb lavale Von Krahli Teatri ja Nargen Opera koostöös. Esitavad Kädy Plaas, Helen Lokuta, Nargen Opera koor ja Tallinna Kammerorkester, dirigent Tõnu Kaljuste

Nargen Opera lummas Kõrvitsa muusikaga / Ruth Alaküla, Andres Laasik

Index Scriptorium Estoniae

Alaküla, Ruth, 1957-

2006-01-01

Von Krahli Teatris Peeter Jalaka lavastuses esietendunud Tõnu Kõrvitsa uued kammerooperid "Tuleaed" ja "Mu luiged, mu mõtted", mille aluseks on luuletaja Marie Heibergi saatus. Libretode autor on Maarja Kangro. Kammerooperid tulevad lavale Von Krahli Teatri ja Nargen Opera koostöös. Esitavad Kädy Plaas, Helen Lokuta, Nargen Opera koor ja Tallinna Kammerorkester, dirigent Tõnu Kaljuste

Zaman Talukder : L'autonomisation des femmes au moyen de la ...

International Development Research Centre (IDRC) Digital Library (Canada)

27 mars 2015 ... Le programme Enhanced Homestead Food Production (EHFP) de l'organisme Helen Keller International bénéficie du soutien technique de Zaman Talukder, expert en agriculture, sécurité alimentaire et nutrition établi au Cambodge. Le travail de Zaman vise à intégrer l'aquaculture d'espèces diverses en ...

Katrin Denev pokazala harakter

Index Scriptorium Estoniae

2006-01-01

Veneetsia 63. filmifestivali auhinnatutest, kellest vaid Stephen Frears'i filmis "Kuninganna" ("The Queen") peaosa kehastanud Helen Mirren oli üks favoriitidest. Parima filmi peaauhind Kuldlõvi läks üllatuslikult Hiina režissööri Jia Zhang-Ke filmile "Vaikelu" ("Dong"). Ka teistest Veneetsia 63. filmifestivali võitjatest. Festivali žüriid juhatas Catherine Deneuve

A Baseline Description of DTIC Scientific and Technical Information Support System

Science.gov (United States)

1986-09-01

discussed below. Operations Research And Economic Analysis Office (DTIC-LO) This organizational element is currently being staffed. Its primary planned... Analysis Centers DASIAC - Ed Martin, Dave Reitz GACIAC - Richard Bartl* MCIAC - Helen Pestel * MMIAC - Sarah Ellingsworth...Overall Organization 2-5 Office Of The Administrator And Personal Staff 2-7 Equal Employment Opportunity Manager 2-7 Information Analysis

African Stories

African Journals Online (AJOL)

Owner

en dié van sy “vriende”, onder wie baie oud- soldate. Die boek begin met 'n roerende vertelling van Venter se besoek in 1964 aan die bekende. Duitse dokter en sendeling Albert Schweitzer in die hedendaagse Gaboen. Schweitzer, wat in 1913 saam met sy vrou Helene 'n hospitaal diep in die ekwatoriale reënwoud op die.

Acute mental health care and South African mental health legislation ...

African Journals Online (AJOL)

Objective: This is the first of three reports on a follow-up review of mental health care at Helen Joseph Hospital (HJH). In this first part, qualitative and quantitative descriptions were made of the services and of demographic and clinical data on acute mental health care users managed at HJH, in a retrospective review of ...

On the Shoulders of Sir Isaac Newton and Arthur Storer

Science.gov (United States)

Martin, Helen E.; Evans-Gondo, Bonita

2013-01-01

Helen E. Martin, the author of this article, is a retired National Board Certified Teacher who has been researching Sir Isaac Newton's unpublished manuscripts for over three decades. While researching the work of Newton, a teacher she was mentoring asked for some hands-on activities to study planetary motion. The description of the activity…

Kas sinul on juba pääsukesed kõhus? / Maris Meiessaar

Index Scriptorium Estoniae

Meiessaar, Maris

2007-01-01

Tallinna Ülikooli reklaami ja imagoloogia eriala tudengid osalesid projektis The Pitch, et leida ideed Eesti toidu ja seda tähistava pääsukese logo reklaamimiseks. Võistluse võitis projekt "Kõhu tunne", autoriteks Birgit Jõgeva, Mariliis Lill, Liina Karo, Helen Kask ja Markko Toppi. Võistlust kommenteerib TLÜ reklaami ja meedia osakonna juhataja Tiina Hiob

Helenistic Encomium: A Reflection on Comics and Rhetoric

Science.gov (United States)

Helms, Jason

2009-01-01

This video reflection starts in a presentation on comics at the Thomas R. Watson Conference last October, which prompted the author to explore the etymology of cosmos and comos through an alternate reading of Gorgias' "Encomium of Helen". The author then works with comos, as revelry, to offer thoughts on comics as a form of multimodal composition…

US Geological Survey activities, fiscal year 1981

International Nuclear Information System (INIS)

1981-01-01

Activities in Alaska, Mount St. Helens, leasing and regulatory procedure, coal, royalty management, water data telemetry, acid rain, hazardous wastes, oil and gas resources, and digital cartography are reviewed. Chemical and nuclear wastes and petroleum exploration in Alaska are discussed. Management issues are addressed. Mapping activities are reported. Water resources, conservation, and earth sciences, are also reviewed

Eesti noor kunst Pariisis

Index Scriptorium Estoniae

2007-01-01

Pariisis Montrouge'is 22. IX-12. X avatud rahvusvahelisel noorte kunstnike näirusel "Jeune creation europeenne / Euroopa noored loojad" näeb ka eesti kunstnike Maarit Murka, Alvar Reisneri, Jaanus Samma, Noolegrupi (Villem Jahu, Triinu Jürves, Harry Rull, Rannar Laur), Laura Kuuse, Helen Meleski, Marge Monko ja Reimo Võsa-Tangsoo töid. Kuraator Anneli Porri

Hydrothermal alteration in Dumoga Barat, Bolaang Mongondow area North Sulawesi

International Nuclear Information System (INIS)

Agus Harjanto' Sutanto; Sutarto; Achmad Subandrio; I Made Suasta; Juanito Salamat; Giri Hartono; Putu Suputra; I Gde Basten; Muhammad Fauzi; Rosdiana

2016-01-01

Bolaang Mongondow is located in central north Sulawesi arm, which is composed of Neogen magmatic arc and potentially contain economic minerals. This condition is behind the research purpose to study the mineral resources potencies. Research aim is to study alteration caused by hydrothermal process and its relation with gold (Au) deposit based on field study and laboratory analysis. Methodologies used for the research are literature study, geological survey, rocks sampling, laboratory analysis, and data processing. Research area is a multiply diorite intrusion complex. Andesite, volcaniclastic rocks, and dacite, the older rocks, were intruded by this complex. Later, dacitic tuff, volcanic sandstone, and alluvium deposited above them. There are three measured and mapped major faults heading NE-SW crossed by E-W fault and NW-SE fault lately crossed all the older faults. Early stage hydrothermal alteration related to the existence of young quartz diorite, showing alteration stage from the potassic center to distal prophylatic. Final stage hydrothermal alteration consist of argilic, advanced argilic, and silica-clay mineral±magnetite±chlorite alteration overlapping the earlier alteration. Mineralization of Cu-Au±Ag in central part of research area or Tayap-Kinomaligan area is mostly associated with potassic altered young quartz diorite and crossed by parallel and stock worked quartz-magnetite-chalcopyrite±bornite vein. (author)

{sup 40}K-{sup 40}Ar dating of the Late Miocene transition from calc-alkaline to alkali basalt series, Northwestern Algeria; Datation {sup 40}K-{sup 40}Ar de la transition du volcanisme calco-alcalin au volcanisme alcalin en Oranie au Miocene superieur

Energy Technology Data Exchange (ETDEWEB)

Louni-Hacini, A; Megartsi, M; Semroud, B [Algiers Univ. (Algeria). Faculte des Sciences; Bellon, H; Maury, R C; Cotten, J; Coutelle, A [Brest Univ., 29 (France); Coulon, C [Aix-Marseille-3 Univ., 13 - Marseille (France)

1995-12-01

Neogene volcanic rocks from the northwestern coast of Algeria include calc-alkaline to shoshonitic andesites and dacites (Sahel of Oran and M`Sirda areas) and alkali basalts (Tafna valley). Seventeen new {sup 40}K-{sup 40}Ar ages indicate that these volcanics were emplaced during two distinct periods, from 11.7 to 7.2 Ma and ca. 4 Ma, respectively. All the andesites and dacites were emplaced during the first period, and their trace element characteristics are typical of subduction -and/or collision- related magmas. They are enriched in large-ion lithophile elements and display negative Nb anomalies. The associated alkali basalts are chemically heterogeneous, and contain variable amounts of TiO{sub 2} and P{sub 2}O{sub 5}. Their multielement plots show either positive or slightly negative Nb anomalies. These features suggest that the Neogene volcanics studied derive from two different types of mantle sources, i.e. an enriched sub-continental mantle and an upper mantle carrying a subduction-related geochemical imprint. The latter component may have inherited its specific signature from an earlier subduction event. This ``orogenic`` imprint tends to disappear through time as the contribution of the sub-continental mantle increases. (authors). 12 refs., 4 figs., 2 tabs.

Textural evidence for high-grade ignimbrites formed by low-explosivity eruptions, Paraná Magmatic Province, southern Brazil

Science.gov (United States)

Luchetti, Ana Carolina F.; Gravley, Darren M.; Gualda, Guilherme A. R.; Nardy, Antonio J. R.

2018-04-01

The Paraná-Etendeka Province is a Lower Cretaceous huge bimodal tholeiitic volcanic province (1 million·km3) that predated the Gondwana breakup. Its silicic portion makes up a total volume of at least 20,000 km3 and in southern Brazil it comprises the Chapecó porphyritic high-Ti trachydacites-dacites and the Palmas microporphyritic-aphyric low-Ti dacites-rhyolites. The widespread silicic sheets are debated in the literature because they bear similarities between lavas and high grade ignimbrites. Here we provide new observations and interpretations for flow units with large, dark, and vesicle-poor lens-shaped blobs surrounded by a light-colored matrix. The textural features (macro- to micro-scale) of these blobs are different from typical pumice and/or fiamme and support a low explosivity pyroclastic origin, possibly low-column fountain eruptions with discharge rates high enough to produce laterally extensive high-grade ignimbrites. Such an interpretation, combined with a conspicuous absence of lithic fragments in the deposits, is aligned with a lack of identified calderas in the Paraná-Etendeka Province. Maximum timescales of crystallization associated with the juvenile blobs and estimated from CSD slopes are on the order of millennia for phenocryst populations and on the order of decades for microphenocryst populations.

Multivariate Analysis, Mass Balance Techniques, and Statistical Tests as Tools in Igneous Petrology: Application to the Sierra de las Cruces Volcanic Range (Mexican Volcanic Belt)

Science.gov (United States)

Velasco-Tapia, Fernando

2014-01-01

Magmatic processes have usually been identified and evaluated using qualitative or semiquantitative geochemical or isotopic tools based on a restricted number of variables. However, a more complete and quantitative view could be reached applying multivariate analysis, mass balance techniques, and statistical tests. As an example, in this work a statistical and quantitative scheme is applied to analyze the geochemical features for the Sierra de las Cruces (SC) volcanic range (Mexican Volcanic Belt). In this locality, the volcanic activity (3.7 to 0.5 Ma) was dominantly dacitic, but the presence of spheroidal andesitic enclaves and/or diverse disequilibrium features in majority of lavas confirms the operation of magma mixing/mingling. New discriminant-function-based multidimensional diagrams were used to discriminate tectonic setting. Statistical tests of discordancy and significance were applied to evaluate the influence of the subducting Cocos plate, which seems to be rather negligible for the SC magmas in relation to several major and trace elements. A cluster analysis following Ward's linkage rule was carried out to classify the SC volcanic rocks geochemical groups. Finally, two mass-balance schemes were applied for the quantitative evaluation of the proportion of the end-member components (dacitic and andesitic magmas) in the comingled lavas (binary mixtures). PMID:24737994

Geology, alteration, mineralization and geochemistry at south of Arghash (Neyshabour

Directory of Open Access Journals (Sweden)

Zahra Karimi Saeid Abadi

2010-11-01

Full Text Available The Arghash area is located 45 km to southwest of Neyshabour. The subvolcanic rocks in the area consist of biotite hornblende quartz monzodiorite porphyry, hornblende biotite quartz monzodiorite porphyry, hornblende monzonite porphyry, biotite hornblende monzonite porphyry, monzodiorite porphyry and biotite quartz monzodiorite porphyry units. The volcanic rocks consist of hornblende biotite dacite, biotite hornblende dacite, and andesite and pillow lava. The plutonic rocks consist of hornblende monzodiorite, hornblende monzonite, quartz monzonite, hornblende quartz monzodiorite, biotite granodiorite, hornblende granodiorite, biotite hornblende granodiorite, biotite quartz diorite and pyroxene dolerite units. Five types of alteration including propylitic, carbonate, argillic, silicification and sericitic were recognized. Those are subdivided into twelve sub-zones based on the mineral abundances and intensity of alteration. Primary pyrite, 3-4%, is found mainly as disseminated. Secondary mineralization includes limonite, hematite and jarosite. Twenty rock chip and 8 stream sediment samples were collected for geochemical exploration. The samples were analysed for Cu, Zn, Pb, Ag and Sb using Atomic Absorbtion Spectrophotometric (AAS method. In stream sediment samples, Cu abundance is 34-58 ppm, Zn 45-422 ppm, Pb 28-42 ppm and Ag 2-12 ppm; whereas in rock chip samples, Cu abundance is 8-1137 ppm, Zn 13-411 ppm, Pb 15-97 ppm and Ag 3-32 ppm.

Multivariate Analysis, Mass Balance Techniques, and Statistical Tests as Tools in Igneous Petrology: Application to the Sierra de las Cruces Volcanic Range (Mexican Volcanic Belt

Directory of Open Access Journals (Sweden)

Fernando Velasco-Tapia

2014-01-01

Full Text Available Magmatic processes have usually been identified and evaluated using qualitative or semiquantitative geochemical or isotopic tools based on a restricted number of variables. However, a more complete and quantitative view could be reached applying multivariate analysis, mass balance techniques, and statistical tests. As an example, in this work a statistical and quantitative scheme is applied to analyze the geochemical features for the Sierra de las Cruces (SC volcanic range (Mexican Volcanic Belt. In this locality, the volcanic activity (3.7 to 0.5 Ma was dominantly dacitic, but the presence of spheroidal andesitic enclaves and/or diverse disequilibrium features in majority of lavas confirms the operation of magma mixing/mingling. New discriminant-function-based multidimensional diagrams were used to discriminate tectonic setting. Statistical tests of discordancy and significance were applied to evaluate the influence of the subducting Cocos plate, which seems to be rather negligible for the SC magmas in relation to several major and trace elements. A cluster analysis following Ward’s linkage rule was carried out to classify the SC volcanic rocks geochemical groups. Finally, two mass-balance schemes were applied for the quantitative evaluation of the proportion of the end-member components (dacitic and andesitic magmas in the comingled lavas (binary mixtures.

Comparison between the chemistry of igneous and hydrothermal biotite in the igneous rocks of Sakhtehesar mountain

OpenAIRE

Farima Ayati; Sayide Mahdevari

2015-01-01

Sakhtehesar mountain is located in Urumieh-Dokhtar magmatic belt and is composed of volcanic and subvolcanic rocks (Pliocene andesite to dacite) which intruded the volcanics and pyroclastics of Paleocene age. Three alteration zones including potassic, phyllic and propylitic are recognized in the area. In this paper, the mineral chemistry of magmatic and primary biotite and the mineral chemistry of biotite in potassic and phyllic alteration zones have been studied. Investigations show that pri...

Ausambad Newfoundlandi eestisoost seenesõpradele / foto: Helen Spencer

Index Scriptorium Estoniae

2008-01-01

Newfoundlandis asuva Brother Brennan Environmental Education Centre (BBEEC) poolt korraldadavatest seenekursustest, mille õppejõuks kutsuti Newfoundlandis seenehuvilistena tuntud Maria ja Andrus Voitk

Helen Mirren viis koju kaks Kuldgloobust / Triin Tael

Index Scriptorium Estoniae

Tael, Triin

2007-01-01

Kuldse Gloobuse auhinna draamakategoorias sai mängufilm "Paabel" ("Babel") : režissöör Alejandro Gonzalez Inarritu : Ameerika Ühendriigid - Mehhiko, 2006. Ka teised Golden Globe filmiauhinna saajad

Eesti jalajälg on tohutu / Helen Urbanik

Index Scriptorium Estoniae

Urbanik, Helen

2006-01-01

Maailma Looduse Fond (WWF) avaldas raporti, mille kohaselt Eesti nn ökoloogiline jalajälg on maailmas suuruselt seitsmes. Lisaks tabel: Riikide ökoloogiline jalajälg inimese kohta aastal 2003 globaalsetes hektarites

Eesti tudengid välismaale õpetajaks / Helen Uldrich

Index Scriptorium Estoniae

Uldrich, Helen

2006-01-01

Tudengiprojekti "Include Me" pakub kahenädalst õpetajapraktikat välismaal. Tallinna koolidesse saabusid õpetajapraktikale noored Saksamaalt, Belgiast ja Hollandist. Eelmisel aastal käisid Tallinna Ülikooli tudengid Belgias ja Saksamaal õpetajapraktikal

Mount St. Helens Future Expected Deposition Scenario (FEDS)

Science.gov (United States)

2011-04-14

sediment plain for the period from 2008 to 2035 is estimated to be 215 M Tons. Sediment transport models using both 1-D HEC - RAS and 2-D MIKE 21C... HEC - RAS software. This mobile-bed tool was developed from a hydraulically-calibrated fixed- bed model utilized in the 2009 Level of Protection...38 3.2 1-D HEC - RAS Model .............................................................................................38 3.2.1 Model

Hitler, Stalin ja Vana Toomas koos / Helen Eelrand

Index Scriptorium Estoniae

Eelrand, Helen, 1971-

2004-01-01

Ajalooliste esemete, eelkõige kommunistliku ja natsionaalsotsialistliku sümboolika müügist. Kommentaarid Riigikogu liikmelt Helir-Valdor Seederilt, okupatsioonimuuseumi töötajalt Rasmus Rausbergilt ja siseministeeriumi pressinõunikult Katrin Videselt. Lisa: Lenin läheb idablokis kaubaks

Isogloss: language and legacy on Mount St. Helens

Science.gov (United States)

E. Dodd

2012-01-01

Nothing standing aboveground today was here thirty years ago. The ground itself wasn't here. Oh, there was ground, but much of it lay below the surface where my boot soles slip a little in the loose pebbles of pumice. Rolling on loose rock and big ideas, for a moment I lose my sense of balance, glancing first at the sky above, then at the nearby peak of Mount St...

Viiv enne kojuminekut / Leo Kunnas ; interv. Helen Arak

Index Scriptorium Estoniae

Kunnas, Leo, 1967-

2006-01-01

Kaitsejõudude Peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas oma perekonnast, lapsepõlvekodust Põlvamaal ja praegusest elamisest Tallinnas, missioonil viibivate sõjaväelaste probleemidest ning eluolust Iraagis. Lisa: Katkend Leo Kunnase raamatust "Viiv pikas sõjas"

A preliminary study of the deterioration of alder and Douglas-fir chips in outdoor piles.

Science.gov (United States)

Ernest. Wright

1954-01-01

In the fall of 1952, E. E. Matson of the Pacific Northwest Forest and Range Experiment Station learned that the Fir-Tex Insulating Board Company bf St. Helens, Oregon was considering mixing alder with Douglas-fir chips for outside storage. Since alder heartwood i s more susceptible to decay than that of Douglas-fir, the question arose whether mixing the two might...

Pärnu Keskkonnahariduskeskus = Pärnu Environmental Education Centre

Index Scriptorium Estoniae

2015-01-01

Pärnu Keskkonnahariduskeskus A.H. Tammsaare puiestee 57, valminud 2013. Arhitektuurivõistlus 2006, jagatud III koht. Võistlustöö autorid Maarja Kask, Karli Luik, Ralf Lõoke (Salto Arhitektuuribüroo). Arhitektid Maarja Kask, Karli Luik, Ralf Lõoke, Helin Kukk, Andro Mänd, Helen Rebane, Margus Tamm. Pärnumaa püsinäituse kujundus Malle Jürgenson, Krista Lepland (Laika, Belka & Strelka)

Browse Author Index

African Journals Online (AJOL)

Skinner, Donald · Skinner, Donald · Skovdal, Morten · Sliep, Yvonne · Smillie, Kirsten · Smit, Jennifer A. Smith, Dawn K · Smith, Helen · Smith, Julia · Smith, Sarah · Snipstad, Mai Bente · Sodemann, Morten · Soko, Mavis · Sone, Albert Mouelle · Souza, Emmanuel · Spark-du Preez1, N · Spiegel, Paul B · Sprague, Courtenay

Camera formation and more, but what comes next? an analysis of volcanic threat of Nisyros island, Greece

International Nuclear Information System (INIS)

Winson, A; Kinvig, H; Gottsmann, J; Partington, E; Geyer, A

2008-01-01

We present an analysis of volcanic threat of Nisyros island (Greece) based on a catalogue of questions compiled for the USGS National Volcano Early Warning System (NVEWS). We find that the score puts Nisyros in the league of volcanoes posing a very high threat. US volcanoes with a comparable threat level include Mt. St. Helens, Augustine and the Long Valley caldera.

Kas tõesti Leonardo da Vinci? / Orest Kormašov

Index Scriptorium Estoniae

Kormašov, Orest, 1964-

2010-01-01

Kadrioru Kunstimuuseumis eksponeeritakse 5.-12. veebruarini 2010 Leonardo da Vinci arvatavat autoportreed ning 6. veebruaril toimub Tallinna Ülikoolis rahvusvaheline konverents "Võti Leonardo juurde" ("A Key to Leonardo"). Maalist, mille itaalia kunstiajaloolane Nicola Barbatelli leidis 2008. a. ühest erakogust Lõuna-Itaalias. Maali uuringutest, milles osalevad Orest Kormašov ja Helen Kokk, kes on loonud Leonardo da Vinci peast kolmedimensioonilise mudeli

Suurbritannias võttis võidu "Kuninganna", kes muu

Index Scriptorium Estoniae

2007-01-01

Stephen Frearsi mängufilm "Kuninganna" ("The Queen") sai parima filmi tiitli ja kuninganna Elizabeth II kehastanud Helen Mirren parima naisnäitleja Bafta (Briti filmiakadeemia auhind). Ka teistest võitjatest : parim lavastaja Paul Greengrass ("United 93"), parim meesnäitleja Forest Whitaker (parim briti film "Shotimaa viimane kuningas"), parim võõrkeelne film "Paani labürint" (Guillermo del Toro)

Vaade minevikku kaljult mere ääres / Helju Koger

Index Scriptorium Estoniae

Koger, Helju, 1943-

2005-01-01

Eesti Vabaõhumuuseumis asuvast Kochidele kuulunud Liberty suvemõisast (arhitekt Otto Schott, 1905), puiesteest Via Appia, Arthur Girard de Soucantoni hävinud villast (arhitekt Rudolf Knüpffer), G. de Soucantoni tütre Helene ja Eugen Von Nottbecki suvilast nr. 15, raidkividest, Etienne Girard de Soucantoni šveitsi villast (praegu muuseumi teadurite töömaja) jm. 11 ill

Trichtlinnburg tõi esile asjad, mida turist ei näe / Liina Siib

Index Scriptorium Estoniae

Siib, Liina

2005-01-01

Ajaloolise linnaruumi säilitamist ja arendamist uuriva Euroopa kultuuriprojekti Trichtlinnburg (TLB) Tallinnas toimunud kunstiprojektidest. Sanja Ivekovici video "(If) I Lived Here", Silja Saarepuu ja Villu Plingi objekt "Plats", Anna-Karin Stjerlofi näidispostkaardid, Jüri Ojaveri projekt "Pääsla", Tiina Tammetalu projekt "Seirajad", Katrin Essensoni ja Helen Becki performance'id, David Bate'i fotosari, TLB jalutuskäigud Tallinnas

Üks uks Eesti ja Jaapani vahel : köitekunst kohtub animatsiooniga / Maarja Undusk

Index Scriptorium Estoniae

Undusk, Maarja

2003-01-01

Eestis viibiv jaapanlanna Maya Yonesho (sünd. 1965) hakkab tegema stipendiaadifilmi "Üks uks". Raamat-uksed teevad valmis eesti nahakunstnikud Külli Grünbach, Rene Haljasmäe, Pille Kivihall, Helen Maran-Poll, Lennart Mänd, Tiina Piisang, Jane Rannamets ja Maarja Undusk. Filmi muusika autor Sven Grünberg. M. Yonesho juhendas nahakunstnik Kadri Halliku diplomitööd

Camera formation and more, but what comes next? an analysis of volcanic threat of Nisyros island, Greece

Energy Technology Data Exchange (ETDEWEB)

Winson, A; Kinvig, H; Gottsmann, J; Partington, E; Geyer, A [Department of Earth Sciences, University of Bristol (United Kingdom)

2008-10-01

We present an analysis of volcanic threat of Nisyros island (Greece) based on a catalogue of questions compiled for the USGS National Volcano Early Warning System (NVEWS). We find that the score puts Nisyros in the league of volcanoes posing a very high threat. US volcanoes with a comparable threat level include Mt. St. Helens, Augustine and the Long Valley caldera.

The eruptive chronology of the Ampato-Sabancaya volcanic complex (Southern Peru)

Science.gov (United States)

Samaniego, Pablo; Rivera, Marco; Mariño, Jersy; Guillou, Hervé; Liorzou, Céline; Zerathe, Swann; Delgado, Rosmery; Valderrama, Patricio; Scao, Vincent

2016-09-01

We have reconstructed the eruptive chronology of the Ampato-Sabancaya volcanic complex (Southern Peru) on the basis of extensive fieldwork, and a large dataset of geochronological (40K-40Ar, 14C and 3He) and geochemical (major and trace element) data. This volcanic complex is composed of two successive edifices that have experienced discontinuous volcanic activity from Middle Pleistocene to Holocene times. The Ampato compound volcano consists of a basal edifice constructed over at least two cone-building stages dated at 450-400 ka and 230-200 ka. After a period of quiescence, the Ampato Upper edifice was constructed firstly during an effusive stage (80-70 ka), and then by the formation of three successive peaks: the Northern, Southern (40-20 ka) and Central cones (20-10 ka). The Southern peak, which is the biggest, experienced large explosive phases, resulting in deposits such as the Corinta plinian fallout. During the Holocene, eruptive activity migrated to the NE and constructed the mostly effusive Sabancaya edifice. This cone comprised many andesitic and dacitic blocky lava flows and a young terminal cone, mostly composed of pyroclastic material. Most samples from the Ampato-Sabancaya define a broad high-K magmatic trend composed of andesites and dacites with a mineral assemblage of plagioclase, amphibole, biotite, ortho- and clino-pyroxene, and Fe-Ti oxides. A secondary trend also exists, corresponding to rare dacitic explosive eruptions (i.e. Corinta fallout and flow deposits). Both magmatic trends are derived by fractional crystallisation involving an amphibole-rich cumulate with variable amounts of upper crustal assimilation. A marked change in the overall eruptive rate has been identified between Ampato ( 0.1 km3/ka) and Sabancaya (0.6-1.7 km3/ka). This abrupt change demonstrates that eruptive rates have not been homogeneous throughout the volcano's history. Based on tephrochronologic studies, the Late Holocene Sabancaya activity is characterised by strong

Late Neoproterozoic adakitic lavas in the Arabian-Nubian shield, Sinai Peninsula, Egypt

Science.gov (United States)

Abdelfadil, Khaled M.; Obeid, Mohamed A.; Azer, Mokhles K.; Asimow, Paul D.

2018-06-01

The Sahiya and Khashabi volcano-sedimentary successions are exposed near the southern tip of the Sinai Peninsula, the northernmost segment of the Arabian-Nubian Shield (ANS). These Neoproterozoic successions include a series of intermediate to acidic lavas and associated pyroclastic deposits. Field observations and geochemical data reveal two distinct eruptive phases. The lavas representing each phase are intercalated with volcaniclastic greywackes and siltstones. The first eruptive phase, well exposed at Wadi Sahiya, includes basaltic andesite, andesite and dacite with minor rhyolite. The rocks of this sequence are at most weakly deformed and slightly metamorphosed. The second eruptive phase, well exposed at Wadi Khashabi, includes only undeformed and unmetamorphosed dacite and rhyolite. The two volcano-sedimentary successions were separated and dismembered during intrusion of post-collisional calc-alkaline and alkaline granites. Geochemical compositions of the Sahiya and Khashabi volcanic rocks confirm the field data indicating discrete phases of magmatism, however all the compositions observed might plausibly be derived from a common source and be related to one another dominantly through fractional crystallization. The low and variable Mg# values (55-33) measured in the basaltic andesites and andesites preclude their equilibration with a mantle source. Rather, even the most primitive observed lavas are already the products of significant fractional crystallization, dominated by removal of amphibole and plagioclase. Continued fractionation eventually produced dacite and rhyolite marked by significant depletion in Y and HREE. The gradual appearance of negative Nb-Ta anomalies with increasing SiO2 through both suites suggests at least some component of progressive crustal contamination. The medium- to high-K calc-alkaline character of the Sahiya and Khashabi volcanics could be explained either by their formation at an active continental margin or by a two

Extensive young silicic volcanism produces large deep submarine lava flows in the NE Lau Basin

Science.gov (United States)

Embley, Robert W.; Rubin, Kenneth H.

2018-04-01

New field observations reveal that extensive (up to 402 km2) aphyric, glassy dacite lavas were erupted at multiple sites in the recent past in the NE Lau basin, located about 200 km southwest of Samoa. This discovery of volumetrically significant and widespread submarine dacite lava flows extends the domain for siliceous effusive volcanism into the deep seafloor. Although several lava flow fields were discovered on the flank of a large silicic seamount, Niuatahi, two of the largest lava fields and several smaller ones ("northern lava flow fields") were found well north of the seamount. The most distal portion of the northernmost of these fields is 60 km north of the center of Niuatahi caldera. We estimate that lava flow lengths from probable eruptive vents to the distal ends of flows range from a few km to more than 10 km. Camera tows on the shallower, near-vent areas show complex lava morphology that includes anastomosing tube-like pillow flows and ropey surfaces, endogenous domes and/or ridges, some with "crease-like" extrusion ridges, and inflated lobes with extrusion structures. A 2 × 1.5 km, 30-m deep depression could be an eruption center for one of the lava flow fields. The Lau lava flow fields appear to have erupted at presumptive high effusion rates and possibly reduced viscosity induced by presumptive high magmatic water content and/or a high eruption temperature, consistent with both erupted composition ( 66% SiO2) and glassy low crystallinity groundmass textures. The large areal extent (236 km2) and relatively small range of compositional variation ( σ = 0.60 for wt% Si02%) within the northern lava flow fields imply the existence of large, eruptible batches of differentiated melt in the upper mantle or lower crust of the NE Lau basin. At this site, the volcanism could be controlled by deep crustal fractures caused by the long-term extension in this rear-arc region. Submarine dacite flows exhibiting similar morphology have been described in ancient

Assembling an ignimbrite: Compositionally defined eruptive packages in the 1912 Valley of Ten Thousand Smokes ignimbrite, Alaska

Science.gov (United States)

Fierstein, J.; Wilson, C.J.N.

2005-01-01

The 1912 Valley of Ten Thousand Smokes (VTTS) ignimbrite was constructed from 9 compositionally distinct, sequentially emplaced packages, each with distinct proportions of rhyolite (R), dacite (D), and andesite (A) pumices that permit us to map package boundaries and flow paths from vent to distal extents. Changing pumice proportions and interbedding relationships link ignimbrite formation to coeval fall deposition during the first ???16 h (Episode I) of the eruption. Pumice compositional proportions in the ignimbrite were estimated by counts on ???100 lapilli at multiple levels in vertical sections wherever accessible and more widely over most of the ignimbrite surface in the VTTS. The initial, 100% rhyolite ignimbrite package (equivalent to regional fall Layer A and occupying ???3.5 h) was followed by packages with increasing proportions of andesite, then dacite, emplaced over ???12.5 h and equivalent to regional fall Layers B1-B3. Coeval fall deposits are locally intercalated with the ignimbrite and show parallel changes in R:D (rhyolite:dacite) proportions, but lack significant amounts of andesite. Andesite was thus dominantly a low-fountaining component in the eruption column and is preferentially represented in packages filling the VTTS north of the vent. The most extensive packages (3 and 4) occur in B1 and early B2 times where flow mobility and volume were optimized; earlier all-rhyolite flows (Package 1) were highly energetic but less voluminous, while later packages (5-9) were both less voluminous and emplaced at lower velocities. Package boundaries are expressed as one or more of the following: sharp color changes corresponding to compositional variations; persistent finer-grained basal parts of flow units; compaction swales filled by later packages; erosional channels cut by the flows that fill them; lobate accumulations of one package; and (mostly south of the vent) intercalated fall deposit layers. Clear flow-unit boundaries are best developed between

Irish Baking Book

OpenAIRE

Ross, Ruth Isabel

1995-01-01

Published by Gill & Macmillan, Goldenbridge, Dublin 8 in 1995 at a cost of £4.99 Irish pounds.Editorial consultant Roberta Reeners, Illustrations by Tom Brady, Design and print origination by Identikit Design Consultants Dublin, index compiled by Helen Litton, printed by the Guernsey Press Ltd. 98p., 19cm., paperback. Access the publisher's website here http://arrow.dit.ie/irckbooks/1006/thumbnail.jpg

The spirituality of 'atheist' student in the secondary school of Athena royal of René Magritte of Lessines

OpenAIRE

Derjacques, Erica Agnes Rita

2017-01-01

This thesis analyses the spirituality of adolescent in two public schools in Belgium. The analysis is done using the book, Cultivating the spirit: How college can enhance students' inner lives by Jennifer Lindholm, Alexander and Helen Astin. The study focused on Five Spiritual Qualities: Spiritual Quest; Equanimity; Ethic of Caring; Charitable Involvement; and Ecumenical Worldview and Five Religious Qualities: Religious Commitment; Religious Engagement; Religious/Social Conservatism; Religiou...

Industry's focus on benefits 'Creates public distrust'

Energy Technology Data Exchange (ETDEWEB)

Mitev, Lubomir [NucNet, Brussels (Belgium)

2015-03-15

The Eagle Project, aimed at identifying and disseminating good practices in information and communication related to ionising radiation, has been carrying out public opinion polls in Europe. NucNet spoke to Genevieve Baumont, senior expert member of the French Expert Commission, and Marie-Helene Eljammal, co-writer of a French Institute for Radiological Protection and Nuclear Safety (IRSN) report on one of the polls, about the results.

"Da Vinci kood" ja Eesti / Reet Rast

Index Scriptorium Estoniae

Rast, Reet, 1964-

2010-01-01

Möödunud kuu kunstisündmuseks oli "Da Vinci koodi avamine" Kadrioru Kunstimuuseumis ja Tallinna Ülikoolis. 5.-12. veebruarini eksponeeriti Kadrioru kunstimuuseumis Leonardo da Vinci arvatavat autoportreed. Lõuna-Itaalia erakogust leitud maali analüüsimisega tegelesid Tallinna Ülikooli maali ja maalitehnoloogia õppejõud Orest Kormašov, kes valmistas klassikalise portreeskulptuuri, arvutisimulatsiooni teostas Eesti Kunstiakadeemia graafilise disaini tudeng Helen Kokk

PÖFF-i alafestivalid lükati käima

Index Scriptorium Estoniae

2010-01-01

14. korda toimuva Pimedate Ööde Filmifestivali tänavune fookus on soome filmidel ja Euroopa filmiauhindade nominentide töödel. PÖFF-i põhiprogrammi tutvustab peakorraldaja Tiina Lokk, tudengi- ja lühifilmide festivali Sleepwalkers kava festivali juht Helen Vinogradov, animafilmide festivali Animated Dreams kava programmijuht Heilika Pikkov, laste- ja noortefilmide festivali Just Film kava festivali juht Mikk Granström

Kiikuv maja / Anu Arm

Index Scriptorium Estoniae

Arm, Anu

2006-01-01

Eesti Kunstiakadeemia esimese kursuse arhitektuuriüliõpilaste II semestri töö. Juhendaja arhitekt Andres Alver, ehitamise Pedaspeale organiseeris suvepraktika juhendaja arhitekt Jaan Tiidemann. Autor Anu Arm, kaasa töötasid ja valmis ehitasid: Ott Alver, Maarja Elm, Mari Hunt, Alvin Järving, Marten Kaevats, Riho Kerge, Reedik Poopuu, Anu Põime, Helen Rebane, Kaisa Saarva, Martin Tago, Reet Volt. Valmis: 19. VIII 2006

Hullud päevad von Krahlis

Index Scriptorium Estoniae

2006-01-01

Von Krahli Teatris mängitakse neil päevi neli korda Peeter Jalaka lavastuses Tõnu Kõrvitsa kammeroopereid "Tuliaed" ja "Mu luiged, mu mõtted", mille aluseks on luuletaja Marie Heibergi saatus. Libreto autor on Maarja Kangro. Kammerooperid tulevad lavale Von Krahli Teatri ja Nargen Opera koostöös. Esitavad Kädy Plaas, Helen Lokuta, Nargen Opera koor ja Tallinna Kammerorkester, dirigent Tõnu Kaljuste

Director murrab pead : Meeskond versus staar / Ergo Metsla

Index Scriptorium Estoniae

Metsla, Ergo

2008-01-01

Küsimusele, kuidas säilitada hästi töötav meeskond ja ka võimekas müügimees, otsivad lahendusi CV-Onlineþi turundusjuht Helen Hinno, Invicta tegevjuht Peeter Puskai, OÜ Sirje Tammiste Konsultatsioonibüroo koolitaja Sirje Tammiste, AS-i NT Marine müügi- ja teenindusjuht Jaan Lember. Vt. ka vastukaja Director nr. 2 lk. 42

Earth observations during Space Shuttle mission STS-45 Mission to Planet Earth - March 24-April 2, 1992

Science.gov (United States)

Pitts, David E.; Helfert, Michael R.; Lulla, Kamlesh P.; Mckay, Mary F.; Whitehead, Victor S.; Amsbury, David L.; Bremer, Jeffrey; Ackleson, Steven G.; Evans, Cynthia A.; Wilkinson, M. J.

1992-01-01

A description is presented of the activities and results of the Space Shuttle mission STS-45, known as the Mission to Planet Earth. Observations of Mount St. Helens, Manila Bay and Mt. Pinatubo, the Great Salt Lake, the Aral Sea, and the Siberian cities of Troitsk and Kuybyshev are examined. The geological features and effects of human activity seen in photographs of these areas are pointed out.

Measuring the Foundation of Homeland Security

Science.gov (United States)

2007-03-01

Pirak Kevin Eack Susan Pyle Chuck Eaneff Joseph Saitta Susan Fernandez Shelly Schechter Helen Fitzpatrick Rick Schwein Jay...multiple disciplines. The scope of this literature review is to cast a broad net and then narrow to specific literature related to Homeland Security...Suez Canal. His successes as a planner, diplomat and promoter made him the most celebrated man in Europe. Because of these successes, De Lesseps

Cultural Resources Investigations of the East and West Bayou Sale Tie-In Levee, St. Mary Parish, Louisiana.

Science.gov (United States)

1998-10-01

Mendez , and Tara Bond 1994 Archaeological Data Recovery at Ashland-Belle Helene Plantation (16AN26), Ascension Parish, Louisiana, Volume III... Caro - lina. Miller, Daniel 1987 Material Culture and Mass Consumption. Basil Blackwell, Oxford, UK. Miller, Daniel and Christopher Tilley 1984...Jones, R. Mendez , H. Franks, and T. Bond. Volume 1, pp. II- I - 1 1-40. Submitted to the Louisiana Division of Archaeology, Baton Rouge. Weinstein

Air pollution dry deposition: radioisotopes as particles and volatiles

International Nuclear Information System (INIS)

Anon.

1981-01-01

This study focuses on determining volcanic ash and ambient airborne solids concentrations at various sampling sites subsequent to the Mt. St. Helens' eruption in order to develop an experimental basis for models predicting removal of airborne particles and gases by dry deposition onto outdoor surfaces. In addition, deposition rates were determined using dual tracer techniques in the field and in a wind tunnel in the laboratory

Tartu Ülikooli Narva Kolledž = Narva College of the University of Tartu

Index Scriptorium Estoniae

2015-01-01

Tartu Ülikooli Narva Kolledž Raekoja plats 2, valminud 2012. Eesti kultuurkapitali aastapreemia 2013. Arhitektid Siiri Vallner, Katrin Koov, Indrek Peil (Kavakava), kaasautorid Heidi Urb, Andro Mänd, Sten-Mark Mändmaa, Maarja Tüür, sisearhitekt Hannes Praks. Kaasa töötasid Kadri Tamme, Kristjan Holm, Liisi Murula, Toomas Pääsuke, Ahti Grünberg, Daniel Marius Reisser, Helen Sarapuu

Transcriptional Regulation by KLF6, A Novel Tumor Suppressor Gene in Prostate Cancer, Through Interaction with HATS and HDACS

Science.gov (United States)

2006-03-01

Kimmelman1, Rui F Qiao1, Goutham Narla2, Asoka Banno1, Nelson Lau3, Paula D Bos1, Nelson Nuñez Rodriguez1, Bertrand C Liang4, Abhijit Guha3, John A...Shen Yao, 1 Asoka Banno, 3 Eldad Hod, 1 Helen L. Reeves, 1 Rui F. Qiao, 3 Olga Camacho-Vanegas, 2 Alice Levine, 1 Alexander Kirschenbaum, 1,4 Andrew M

Industry's focus on benefits 'Creates public distrust'

International Nuclear Information System (INIS)

Mitev, Lubomir

2015-01-01

The Eagle Project, aimed at identifying and disseminating good practices in information and communication related to ionising radiation, has been carrying out public opinion polls in Europe. NucNet spoke to Genevieve Baumont, senior expert member of the French Expert Commission, and Marie-Helene Eljammal, co-writer of a French Institute for Radiological Protection and Nuclear Safety (IRSN) report on one of the polls, about the results.

El miedo como arma de dominación: admiración, pavor y victoria en la imagen del rey guerrero en el helenismo inicial

Directory of Open Access Journals (Sweden)

Molina Marín, Antonio Ignacio

2014-12-01

Full Text Available The King was the most important figure of all the Hellenistic period. He was an invincible warrior, wise ruler, god, general and medicine man. All these aspects of Hellenistic kingship are well known, however there is one subject that has not been studied by scholars, namely the capacity of Hellenistic kings to scare their enemies with their mere presence. In this paper we analyze stories attaching to Perdiccas, Olympias, Pyrrhus and Alexander the Great. Our opinion is that all these stories are based on the same model, the fight between Achilles and Trojans in the Iliad (XVIII 203-23. The aegis is studied as the mythical justification of the invincibility and terribleness of the kings. Furthermore, we consider the possibility that this phenomenon was associated with the Macedonian kings prior to Alexander.El rey fue la figura más importante de todo el período helenístico. Fue un guerrero invencible, un gobernante sabio, dios, general y curador. Todos estos aspectos sobre la monarquía helenística son bien conocidos, sin embargo hay una cuestión que no ha sido estudiada por los investigadores, es decir, la capacidad de los reyes helenísticos para hacer huir a sus enemigos conmoviéndolos por el miedo con su mera presencia. En este artículo analizamos historias relacionadas con Pérdicas, Olimpíade, Pirro y Alejandro Magno. Nuestra opinión es que todas estas historias están basadas en el mismo modelo, la lucha entre Aquiles y los troyanos en la Ilíada (XVIII 203-23. La égida es estudiada como la justificación mítica de la invencibilidad y terribilidad de los reyes. Además, contemplamos la posibilidad de que este fenómeno estuviese asociado con los reyes de Macedonia antes de Alejandro.

Effects of catastrophic floods and debris flows on the sediment retention structure, North Fork Toutle River, Washington

Science.gov (United States)

Denlinger, Roger P.

2012-01-01

The eruption of Mount St. Helens in 1980 produced a debris avalanche that flowed down the upper reaches of the North Fork Toutle River in southwestern Washington, clogging this drainage with sediment. In response to continuous anomalously high sediment flux into the Toutle and Cowlitz Rivers resulting from this avalanche and associated debris flows, the U.S. Army Corps of Engineers completed a Sediment Retention Structure (SRS) on the North Fork Toutle River in May 1989. For one decade, the SRS effectively blocked most of the sediment transport down the Toutle River. In 1999, the sediment level behind the SRS reached the elevation of the spillway base. Since then, a higher percentage of sediment has been passing the SRS and increasing the flood risk in the Cowlitz River. Currently (2012), the dam is filling with sediment at a rate that cannot be sustained for its original design life, and the U.S. Army Corps of Engineers is concerned with the current ability of the SRS to manage floods. This report presents an assessment of the ability of the dam to pass large flows from three types of scenarios (it is assumed that no damage to the spillway will occur). These scenarios are (1) a failure of the debris-avalanche blockage forming Castle Lake that produces a dambreak flood, (2) a debris flow from failure of that blockage, or (3) a debris flow originating in the crater of Mount St. Helens. In each case, the flows are routed down the Toutle River and through the SRS using numerical models on a gridded domain produced from a digital elevation model constructed with existing topography and dam infrastructure. The results of these simulations show that a structurally sound spillway is capable of passing large floods without risk of overtopping the crest of the dam. In addition, large debris flows originating from Castle Lake or the crater of Mount St. Helens never reach the SRS. Instead, debris flows fill the braided channels upstream of the dam and reduce its storage

Revised tephra volumes for Cascade Range volcanoes

Science.gov (United States)

Nathenson, Manuel

2017-01-01

Isopach maps from tephra eruptions from Mount St. Helens were reported in Carey et al. (1995) and for tephra eruptions from Glacier Peak in Gardner et al. (1998). For exponential thinning, the isopach data only define a single slope on a log thickness versus square root of area plot. Carey et al. (1995) proposed a model that was used to estimate a second slope, and volumes were presented in both studies using this model. A study by Sulpizio (2005) for estimating the second slope and square root of area where the lines intersect involves a systematic analysis of many eruptions to provide correlation equations. The purpose of this paper is to recalculate the volumes of Cascades eruptions and compare results from the two methods. In order to gain some perspective on the methods for estimating the second slope, we use data for thickness versus distance beyond the last isopach that are available for some of the larger eruptions in the Cascades. The thickness versus square root of area method is extended to thickness versus distance by developing an approximate relation between the two assuming elliptical isopachs with the source at one of the foci. Based on the comparisons made between the Carey et al. (1995) and Sulpizio (2005) methods, it is felt that the later method provides a better estimate of the second slope. For Mount St. Helens, the estimates of total volume using the Sulpizio (2005) method are generally smaller than those using the Carey et al. (1995) method. For the volume estimates of Carey et al. (1995), the volume of the May 18, 1980, eruption of Mount St. Helens is smaller than six of the eight previous eruptions. With the new volumes using the Sulpizio (2005) method, the 1980 eruption is smaller in volume than the upper end of the range for only three of the layers (Wn, Ye, and Yn) and is the same size as layer We. Thus the 1980 eruption becomes representative of the mid-range of volumes rather than being in the lower range.

Alterasi Akibat Proses Hidrothermal di Bolaang Mongondow, Provinsi Sulawesi Utara

Directory of Open Access Journals (Sweden)

Agus Harjanto

2016-05-01

Full Text Available Bolaang Mongondow is located in central north Sulawesi arm, which is composed of Neogen magmatic arc and potentially contain economic minerals. This condition is behind the research purpose to study the mineral resources potencies. Research aim is to study alteration caused by hydrothermal process and its relation with gold (Au deposit based on field study and laboratory analysis. Methodologies used for the research are literature study, geological survey, rocks sampling, laboratory analysis, and data processing. Research area is a multiply diorite intrusion complex. Andesite, volcaniclastic rocks, and dacite, the older rocks, were intruded by this complex. Later, dacitic tuff, volcanic sandstone, and alluvium deposited above them. There are three measured and mapped major faults heading NE-SW crossed by E-W fault and NW-SE fault lately crossed all the older faults. Early stage hydrothermal alteration related to the existence of young quartz diorite, showing alteration stage from the potassic center to distal prophyllitic. Final stage hydrothermal alteration consist of argilic, advanced argilic, and silica-clay mineral±magnetite±chlorite alteration overlapping the earlier alteration. Mineralization of Cu-Au±Ag in central part of research area or Tayap-Kinomaligan area is mostly asociated with potassic altered young quartz diorite and crossed by paralel and stockworked quartz-magnetite-chalcopyrite±bornite vein.

The Chahnaly low sulfidation epithermal gold deposit, western Makran volcanic arc, southeastern Iran

Science.gov (United States)

Sholeh, Ali; Rastad, Ebrahim; Huston, David L.; Gemmell, J. Bruce; Taylor, Ryan D.

2016-01-01

The Chahnaly low-sulfidation epithermal Au deposit and nearby Au prospects are located northwest of the intermittently active Bazman stratovolcano on the western end of the Makran volcanic arc, which formed as the result of subduction of the remnant Neo-Tethyan oceanic crust beneath the Lut block. The arc hosts the Siah Jangal epithermal and Kharestan porphyry prospects, near Taftan volcano, as well as the Saindak Cu-Au porphyry deposit and world-class Reko Diq Cu-Au porphyry deposit, near Koh-i-Sultan volcano to the east-northeast in Pakistan. The host rocks for the Chahnaly deposit include early Miocene andesite and andesitic volcaniclastic rocks that are intruded by younger dacitic domes. Unaltered late Miocene dacitic ignimbrites overlie these rocks. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb zircon geochronology data yield ages between 21.8 and 9.9 Ma for the acidic-intermediate regional volcanism. The most recent volcanic activity of the Bazman stratovolcano involved extrusion of an olivine basalt during Pliocene to Quaternary times. Interpretation of geochemical data indicate that the volcanic rocks are synsubduction and calc-alkaline to subalkaline. The lack of a significant negative Eu anomaly, a listric-shaped rare earth element pattern, and moderate La/Yb ratios of host suites indicate a high water content of the source magma.

Geology of the hills in the region of the City of Santiago de Chile: New isotopic constraints

International Nuclear Information System (INIS)

Vergara, M; Lopez-Escobar, I; Palma, J.L; Hickey-Vargas, R

2001-01-01

Geological, geochronological and geochemical data demonstrate that the area where the city of Santiago de Chile is established used to be a huge volcanic field. At present, it is possible to distinguish in the area at least three volcanic cycles, which are geographically superimposed and deeply eroded. The first is Oligocene in age, the second Lower to Middle Miocene and the third is Middle to Upper Miocene. The Oligocene cycle is represented by volcanic and volcanoclastic rocks of the Provincia-San Ramon-Abanico and Conchali belts, and welded tuffs of the San Cristobal and Renca hills. The Lower to Middle Miocene cycle consists of subvolcanic rocks, mostly of basaltic to basaltic-andesite composition, characterized by the presence of clino- and orthopyroxene. The Middle to Upper Miocene cycle is composed predominantly of amphibole-bearing subvolcanic rocks of dacitic composition. The latter are found at the Manquehue hill, which limits the northern part of the city, and the hills at the Rinconada de Conchali. In this communication, we present new Sr-, Nd- and Pb- isotope data obtained from two subvolcanic samples of basaltic composition collected from the San Cristobal hill and at the Santa Lucia hill (Lower to Middle Miocene) and one amphibole-bearing subvolcanic sample of dacitic composition from the Manquehue hill (Middle to Upper Miocene) (au)

Komatiites and nickel sulfide ores of the Black Swan area, Yilgarn Craton, Western Australia. 2: Geology and genesis of the orebodies

Science.gov (United States)

Dowling, S. E.; Barnes, S. J.; Hill, R. E. T.; Hicks, J. D.

2004-11-01

The Black Swan Ultramafic Succession hosts a number of magmatic Fe Ni Cu PGE sulfide ore shoots, ranging from high grade massive ore to low grade disseminated sulfides. Of these, the most economically significant is the Silver Swan massive sulfide orebody, associated with the basal contact of the succession. The deposit varies in thickness between 5 and 20 m, reaches a N S strike length of 75 m, extends for at least 1.2 km of vertical plunge and is open at depth. Overlying matrix (net-textured) ore is rare. Inclusions of dacite are abundant within the lower 5 m of the massive sulfide. They range from angular fragments through smooth sinuous and plumose morphologies to fine lace-like intergrowths with the sulfide matrix, and comprise variable proportions of cores of porphyritic dacite and carapaces with skeletal plagioclase phenocrysts. Dynamic crystallisation and kinetic melting textures in the carapaces indicate that the inclusions have been heated to various temperatures, some well above their liquidus temperature. The composition of the inclusions ranges from a perfect match with the immediate footwall dacites to mixtures of dacite with up to 30% komatiite. The consistent thickness of the inclusion-bearing basal layer within the massive sulphide is interpreted as the extent of 3-D physical connectivity between the inclusions and a partially molten underlying hybrid layer. Primary contacts between the Silver Swan massive sulfide orebody and overlying ultramafic rocks are marked by thin rinds containing coarse-grained chevron-textured chromites with skeletal textures. Compositions of these chromites match those from Kambalda, Perseverance and other localities, and are inconsistent with a metamorphic origin. They are interpreted as markers of primary magmatic contacts. The combination of this feature with the general paucity of matrix ore implies that the massive ore accumulated and solidified before the accumulation of the overlying thick sequence of olivine

Reconstructing multiple arc-basin systems in the Altai-Junggar area (NW China): Implications for the architecture and evolution of the western Central Asian Orogenic Belt

Science.gov (United States)

Li, Di; He, Dengfa; Tang, Yong

2016-05-01

The Altai-Junggar area in northwestern China is a critical region to gain insights on the tectonic framework and geological evolution of the western Central Asian Orogenic Belt (CAOB). In this study, we report results from integrated geological, geochemical and geophysical investigations on the Wulungu Depression of the Junggar Basin to determine the basement nature of the basin and understand its amalgamation history with the Chinese Altai, within the broad tectonic evolution of the Altai-Junggar area. Based on borehole and seismic data, the Wulungu Depression is subdivided into two NW-trending tectonic units (Suosuoquan Sag and Hongyan High) by southward-vergent thrust faults. The Suosuoquan Sag consists of the Middle-Late Devonian basaltic andesite, andesite, dacite, tuff, tuffaceous sandstone and tuffite, and the overlying Early Carboniferous volcano-sedimentary sequence with lava flows and shallow marine sediments from a proximal juvenile provenance (zircon εHf(t) = 6.0-14.9), compared to the Late Carboniferous andesite and rhyolite in the Hongyan High. Zircon SIMS U-Pb ages for dacites and andesites indicate that these volcanics in the Suosuoquan Sag and Hongyan High erupted at 376.3 Ma and 313.4 Ma, respectively. The Middle-Late Devonian basaltic andesites from well LC1 are calc-alkaline and exhibit primitive magma-like MgO contents (7.9-8.6%) and Mg# values (66-68), with low initial 87Sr/86Sr (0.703269-0.704808) and positive εNd(t) values (6.6-7.6), and relatively high Zr abundance (98.2-116.0 ppm) and Zr/Y ratios (5.1-5.4), enrichment in LREEs and LILEs (e.g., Th and U) and depletion in Nb, Ta and Ti, suggesting that they were probably derived from a metasomatized depleted mantle in a retro-arc extensional setting. The well LC1 andesitic tuffs, well L8 dacites, well WL1 dacitic tuffs and well L5 andesites belong to calc-alkaline and metaluminous to peraluminous (A/CNK = 0.8-1.7) series, and display low Mg# values (35-46) and variably positive εNd(t) (4

An Arab NATO in the Making Middle Eastern Military Cooperation Since 2011

Science.gov (United States)

2016-09-01

more pressing every day.”43 King Hamad of Bahrain shortly thereafter backed this call, whereas Tunisia’s foreign minister called it “neither...ava- lon.law.yale.edu/20th_century/arabjoin.asp. 6. Helene von Bismarck, British Policy in the Persian Gulf, 1961-1968: Conceptions of Informal...military cooperation deal,” BBC Monitoring, September 25, 2014; Ammun News website, “ King Abdullah attends joint Jordanian-Emirati military drill

A Sparsity-based Framework for Resolution Enhancement in Optical Fault Analysis of Integrated Circuits

Science.gov (United States)

2015-01-01

discussions and collaboration. I also want to thank other co-workers for discussions and their contributions, Dr. Helen Fawcett, Dr. Euan Ramsay , Dr...optical fault analysis techniques Gordon E. Moore predicted the rapid decrease in IC dimensions (Moore, 1998) and this decrease continues as predicted...Serrels, K. A., Ramsay , E., Warburton, R. J., and Reid, D. T. (2008). Nanoscale optical microscopy in the vectorial focusing regime. Nature Photonics, 2(5

From Humanitarian Intervention to the Responsibility to Protect: From Kosovo to Libya and Beyond

Science.gov (United States)

2011-12-01

attacking bridges, highways, airports, telecommunications facilities, electrical production, factories, and oil refineries. 13 Many of these targets...22, no. 3 (September 2008): 285. 29 MAJ Helene E. Caras , ―Humanitarian Intervention in Kosovo: The Importance of Legal and Moral Issues‖ (monograph...Libya resolution to crusades.‖ reuters.com. 21 March 2011. http://www.reuters.com/article/2011/03/21/us-libya-russia-idUSTRE72K3JR20110321. Caras

Emergency Support Function 15: Communication Synchronization during Defense Support of Civil Authorities Operations

Science.gov (United States)

2015-06-12

for the future. I would like to thank my parents Juan and Helen for their love, support, and guidance; your hard work and sacrifices have given me...required support to civil authortities during emergency relief operations.9 Once civil authorites are capable of resuming responsibility for the...Freeman posit the researcher has an understanding of the cognitive styles of the program stakeholders which will increase access and comprehension of

Fifth international fungus spore conference

Energy Technology Data Exchange (ETDEWEB)

Timberlake, W.E.

1993-04-01

This folio contains the proceedings of the Fifth International Fungal Spore Conference held August 17-21, 1991 at the Unicoi State Park at Helen, Georgia. The volume contains abstracts of each oral presentation as well as a collection of abstracts describing the poster sessions. Presentations were organized around the themes (1) Induction of Sporulation, (2) Nuclear Division, (3) Spore Formation, (4) Spore Release and Dispersal, and (4) Spore Germination.

Fifth international fungus spore conference. [Abstracts]: Final technical report

Energy Technology Data Exchange (ETDEWEB)

Timberlake, W.E.

1993-04-01

This folio contains the proceedings of the Fifth International Fungal Spore Conference held August 17-21, 1991 at the Unicoi State Park at Helen, Georgia. The volume contains abstracts of each oral presentation as well as a collection of abstracts describing the poster sessions. Presentations were organized around the themes (1) Induction of Sporulation, (2) Nuclear Division, (3) Spore Formation, (4) Spore Release and Dispersal, and (4) Spore Germination.

Eestisse jõuab arvatav Leonardo da Vinci autoportree / Maiki Voore

Index Scriptorium Estoniae

Voore, Maiki, 1983-

2010-01-01

5.-12. veebruarini eksponeeritakse Kadrioru kunstimuuseumis Leonardo da Vinci arvatavat autoportreed. 5. veebruaril on kunstimuuseumis maali pidulik esitlus, 6. veebruaril avatakse Tallinna ülikoolis maali analüüse tutvustav rahvusvaheline konverents "Da Vinci kood". Lõuna-Itaalia erakogust leitud maali analüüsimisega tegelesid Tallinna Ülikooli maali ja maalitehnoloogia õppejõud Orest Kormašov, kes valmistas klassikalise portreeskulptuuri, arvutisimulatsiooni teostas Eesti Kunstiakadeemia graafilise disaini tudeng Helen Kokk

Sul on miljoni dollari idee? Nemad aitavad sul selle rahaks teha / Tanel Veenre

Index Scriptorium Estoniae

Veenre, Tanel, 1977-

2010-01-01

Eesti kultuurivahendajatest, nende nappusest. Kultuurikorraldusest, loomest ja ettevõtlusest, kultuuriturundusest, loomemajandusest, mänedžeri ja looja koostööst, kultuuri ekspordist. Kultuurikorraldajate koolitusest Tartu Ülikoolis ning Eesti Muusika- ja Teatriakadeemias. Arvamust avaldavad galerist Olga Temnikova, Eesti Disainerite Liidu esimees Ilona Gurjanova, kontserdikorraldaja Helen Sildna, Ville Jehe disainibüroost Keha3, Von Krahli Teatri projektijuht Elo-Liis Parmas, moekorraldaja Merilyn Kesküla jt.

Waterborne Commerce of the United States Calendar Year 1987. Part 4. Waterways and Harbors Pacific Coast, Alaska and Hawaii

Science.gov (United States)

1989-05-31

AND UNAR OR DRY CARGO TANKER AN TASER DRY CARGO TUGBOAT DR CARGO RUGASO SK3G4 AY IARBOR, ALASKA..(CONTINJED) INJ8IJJND OJTBOJND 25...122 Colombia River Entrance, Oreg., and Lewis River, Wash. ---- 59, 119 Wash. ------------ 40, 115 Long Beach Harbor, Calif. ,----- 4 105...6, 105 Colombia Rsver, Portn other than Portland, Lynn Canal, blask--------5. 128 Astoria, St. Helens, Longvien, Vanvoover, and Kala -------- 4