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Sample records for volcano chile continues

  1. Chiliques volcano, Chile

    Science.gov (United States)

    2002-01-01

    A January 6, 2002 ASTER nighttime thermal infrared image of Chiliques volcano in Chile shows a hot spot in the summit crater and several others along the upper flanks of the edifice, indicating new volcanic activity. Examination of an earlier nighttime thermal infrared image from May 24,2000 showed no thermal anomaly. Chiliques volcano was previously thought to be dormant. Rising to an elevation of 5778 m, Chiliques is a simple stratovolcano with a 500-m-diameter circular summit crater. This mountain is one of the most important high altitude ceremonial centers of the Incas. It is rarely visited due to its difficult accessibility. Climbing to the summit along Inca trails, numerous ruins are encountered; at the summit there are a series of constructions used for rituals. There is a beautiful lagoon in the crater that is almost always frozen.The daytime image was acquired on November 19, 2000 and was created by displaying ASTER bands 1,2 and 3 in blue, green and red. The nighttime image was acquired January 6, 2002, and is a color-coded display of a single thermal infrared band. The hottest areas are white, and colder areas are darker shades of red. Both images cover an area of 7.5 x 7.5 km, and are centered at 23.6 degrees south latitude, 67.6 degrees west longitude.Both images cover an area of 7.5 x 7.5 km, and are centered at 23.6 degrees south latitude, 67.6 degrees west longitude.These images were acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.ASTER is one of five Earth-observing instruments launched December 18,1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U

  2. Interdisciplinary studies of eruption at Chaiten Volcano, Chile

    Science.gov (United States)

    John S. Pallister; Jon J. Major; Thomas C. Pierson; Richard P. Hoblitt; Jacob B. Lowenstern; John C. Eichelberger; Lara. Luis; Hugo Moreno; Jorge Munoz; Jonathan M. Castro; Andres Iroume; Andrea Andreoli; Julia Jones; Fred Swanson; Charlie Crisafulli

    2010-01-01

    There was keen interest within the volcanology community when the first large eruption of high-silica rhyolite since that of Alaska's Novarupta volcano in 1912 began on 1 May 2008 at Chaiten volcano, southern Chile, a 3-kilometer-diameter caldera volcano with a prehistoric record of rhyolite eruptions. Vigorous explosions occurred through 8 May 2008, after which...

  3. A dynamical analysis of the seismic activity of Villarrica volcano (Chile) during September-October 2000

    Energy Technology Data Exchange (ETDEWEB)

    Tarraga, Marta [Departamento de Volcanologia. Museo Nacional de Ciencias Naturales, CSIC, Madrid (Spain)], E-mail: martat@mncn.csic.es; Carniel, Roberto [Dipartimento di Georisorse e Territorio, Universita di Udine, Via Cotonificio 114, 33100 Udine (Italy)], E-mail: roberto.carniel@uniud.it; Ortiz, Ramon; Garcia, Alicia [Departamento de Volcanologia. Museo Nacional de Ciencias Naturales, CSIC, Madrid (Spain); Moreno, Hugo [Observatorio Volcanologico de los Andes del Sur (OVDAS), Servicio Nacional de Geologia y Mineria de Chile (SERNAGEOMIN), Temuco, IX Region (Chile)

    2008-09-15

    Although Villarrica volcano in Chile is one of the most active in the southern Andes, the literature studying its seismic activity is relatively scarce. An interesting problem recently tackled is the possibility for a regional tectonic event to trigger a change in the volcanic activity of this basaltic to basaltic-andesitic volcano, which is in turn reflected in the time evolution of the properly volcanic seismicity, especially in the form of a continuous volcanic tremor. In this work, we conduct a spectral, dynamical and statistical analysis of the tremor recorded during September and October 2000, in order to characterize the anomalous behaviour of the volcano following a tectonic event recorded on 20th September 2000. The observed dynamical transitions are compared with remote sensing and visual observations describing the changes in the eruptive style of the volcano.

  4. A dynamical analysis of the seismic activity of Villarrica volcano (Chile) during September-October 2000

    International Nuclear Information System (INIS)

    Tarraga, Marta; Carniel, Roberto; Ortiz, Ramon; Garcia, Alicia; Moreno, Hugo

    2008-01-01

    Although Villarrica volcano in Chile is one of the most active in the southern Andes, the literature studying its seismic activity is relatively scarce. An interesting problem recently tackled is the possibility for a regional tectonic event to trigger a change in the volcanic activity of this basaltic to basaltic-andesitic volcano, which is in turn reflected in the time evolution of the properly volcanic seismicity, especially in the form of a continuous volcanic tremor. In this work, we conduct a spectral, dynamical and statistical analysis of the tremor recorded during September and October 2000, in order to characterize the anomalous behaviour of the volcano following a tectonic event recorded on 20th September 2000. The observed dynamical transitions are compared with remote sensing and visual observations describing the changes in the eruptive style of the volcano

  5. Observations of rapid-fire event tremor at Lascar volcano, Chile

    Directory of Open Access Journals (Sweden)

    H. Rademacher

    1996-06-01

    Full Text Available During the Proyecto de Investigaciòn Sismològica de la Cordillera Occidental (PISCO '94 in the Atacama desert of Northern Chile, a continuously recording broadband seismic station was installed to the NW of the currently active volcano, Lascar. For the month of April, 1994, an additional network of three, short period, three-component stations was deployed around the volcano to help discriminate its seismic signals from other local seismicity. During the deployment, the volcanic activity at Lascar appeared to be limited mainly to the emission of steam and SO2. Tremor from Lascar is a random, «rapid-fire» series of events with a wide range of amplitudes and a quasi-fractal structure. The tremor is generated by an ensemble of independent elementary sources clustered in the volcanic edifice. In the short-term, the excitation of the sources fluctuates strongly, while the long-term power spectrum is very stationary.

  6. Continuous monitoring of volcanoes with borehole strainmeters

    Science.gov (United States)

    Linde, Alan T.; Sacks, Selwyn

    Monitoring of volcanoes using various physical techniques has the potential to provide important information about the shape, size and location of the underlying magma bodies. Volcanoes erupt when the pressure in a magma chamber some kilometers below the surface overcomes the strength of the intervening rock, resulting in detectable deformations of the surrounding crust. Seismic activity may accompany and precede eruptions and, from the patterns of earthquake locations, inferences may be made about the location of magma and its movement. Ground deformation near volcanoes provides more direct evidence on these, but continuous monitoring of such deformation is necessary for all the important aspects of an eruption to be recorded. Sacks-Evertson borehole strainmeters have recorded strain changes associated with eruptions of Hekla, Iceland and Izu-Oshima, Japan. Those data have made possible well-constrained models of the geometry of the magma reservoirs and of the changes in their geometry during the eruption. The Hekla eruption produced clear changes in strain at the nearest instrument (15 km from the volcano) starting about 30 minutes before the surface breakout. The borehole instrument on Oshima showed an unequivocal increase in the amplitude of the solid earth tides beginning some years before the eruption. Deformational changes, detected by a borehole strainmeter and a very long baseline tiltmeter, and corresponding to the remote triggered seismicity at Long Valley, California in the several days immediately following the Landers earthquake are indicative of pressure changes in the magma body under Long Valley, raising the question of whether such transients are of more general importance in the eruption process. We extrapolate the experience with borehole strainmeters to estimate what could be learned from an installation of a small network of such instruments on Mauna Loa. Since the process of conduit formation from the magma sources in Mauna Loa and other

  7. The 2008 Eruption of Chaitén Volcano, Chile and National Volcano-Monitoring Programs in the U.S. and Chile

    Science.gov (United States)

    Ewert, J. W.; Lara, L. E.; Moreno, H.

    2008-12-01

    Chaitén volcano, southern Chile, began erupting on 2 May 2008. The eruption produced 3 Plinian eruption pulses between May 2 and 8. Between Plinian phases the volcano emitted a constant column of ash to approximately 10 km, gradually diminishing to approximately 3 km by the end of June. The eruption of Chaitén was remarkable on several counts--it was the first rhyolite eruption on the planet since Novarupta (Katmai) erupted in 1912, and Chaitén had apparently lain dormant for approximately 9300 years. Though Chaitén is located in a generally sparsely populated region, the eruption had widespread impacts. More than 5000 people had to be quickly evacuated from proximal areas and aviation in southern South America was disrupted for weeks. Within 10 days secondary lahars had overrun much of the town of Chaitén complicating the prospects of the townspeople to return to their homes. Prior to the eruption onset, the nearest real-time seismic station was 300 km distant, and earthquakes were not felt by local citizens until approximately 30 hours before the eruption onset. No other signs of unrest were noted. Owing to the lack of near-field monitoring, and the nighttime eruption onset, there was initial confusion about which volcano was erupting: Chaitén or nearby Michinmahuida. Lack of monitoring systems at Chaitén meant that warning time for the public at risk was extremely short, and owing to the nature of the eruption and the physical geography of the area, it was very difficult to install monitoring instruments to track its progress after the eruption started. The lack of geophysical monitoring also means that an important data set on precursory behavior for silicic systems was not collected. With more than 120 Pleistocene to Holocene-age volcanoes within its continental territory, Chile is one of the more volcanically active countries in the world. The eruption of Chaitén has catalyzed the creation of a new program within the Servicio Nacional de Geología y

  8. Effects of volcanic and hydrologic processes on forest vegetation: Chaitén Volcano, Chile

    Science.gov (United States)

    Frederick J. Swanson; Julia A. Jones; Charles M. Crisafulli; Antonio. Lara

    2013-01-01

    The 2008-2009 eruption of Chaiten Volcano (Chile) involved a variety of volcanic and associated hydrologic processes that damaged nearby forests. These processes included coarse (gravel) and fine (silt to sand) tephra fall, a laterally directed blast, fluvial deposition of remobilized tephra, a variety of low-temperature mass-movement processes, and a pyroclastic flow...

  9. Intense Seismic Activity at Chiles and Cerro Negro Volcanoes on the Colombia-Ecuador Border

    Science.gov (United States)

    Torres, R. A.; Cadena, O.; Gomez, D.; Ruiz, M. C.; Prejean, S. G.; Lyons, J. J.; White, R. A.

    2015-12-01

    The region of Chiles and Cerro Negro volcanoes, located on the Colombian-Ecuadorian border, has experienced an ongoing seismic swarm beginning in Aug. 2013. Based on concern for local residents and authorities, a cooperative broadband monitoring network was installed by the Servicio Geológico Colombiano in Colombia and the Instituto Geofísico of the Escuela Politécnica Nacional in Ecuador. Since November 2013 more than 538,000 earthquakes were recorded; although since May 2015 the seismicity has decreased significantly to an average of 70 events per day. Three large earthquake swarms with increasing energy occurred in Aug.-Oct. 2013, March-May 2014, and Sept.-Dec. 2014. By the end of 2014, roughly 400 earthquakes greater than M 3 had occurred with a maximum rate of 8000 earthquakes per day. The largest earthquake was a 5.6 ML on Oct. 20, 2014. This event produced an InSAR coseismic deformation of ~23 cm (S. Ebmeier, personal communication). Most events are typical brittle failure volcano-tectonic (VT) earthquakes that are located in a cluster beneath the southern flank of Chiles volcano, with depths between 1.5 and 10 km. Although the great majority of earthquakes are VT, some low-frequency (LF, ~0.5 Hz) and very-low-frequency (VLF) events have occurred. Particle motion analysis suggests that the VLF source migrated with time. While a VLF on Oct. 15, 2014 was located south of Chiles volcano, near the InSAR source, the VLF registered on Feb. 14, 2015 was likely located very close to Chiles Volcano. We infer that magma intrusion and resulting fluid exsolution at depths greater than 5 km are driving seismicity in the Chiles-Cerro Negro region. However earthquakes are failing in a manner consistent with regional tectonics. Relative relocations reveal a structure consistent with mapped regional faults. Thus seismicity is likely controlled by an interaction of magmatic and tectonic processes. Because the regional stress field is highly compressional and the volcanoes

  10. Effects of volcanic and hydrologic processes on forest vegetation: Chaitén Volcano, Chile

    OpenAIRE

    Swanson,Frederick J; Jones,Julia A; Crisafulli,Charles M; Lara,Antonio

    2013-01-01

    The 2008-2009 eruption of Chaitén Volcano (Chile) involved a variety of volcanic and associated hydro-logic processes that damaged nearby forests. These processes included coarse (gravel) and fine (silt to sand) tephra fall, a laterally directed blast, fluvial deposition of remobilized tephra, a variety of low-temperature mass-movement processes, and a pyroclastic flow. Each of these geophysical processes constitutes a type of ecosystem disturbance which involves a distinctive suite of distur...

  11. Interdisciplinary Studies of Eruption at Chaitén Volcano, Chile

    Science.gov (United States)

    Pallister, John S.; Major, Jon J.; Pierson, Thomas C.; Hoblitt, Richard P.; Lowenstern, Jacob B.; Eichelberger, John C.; Lara, Luis; Moreno, Hugo; Muñoz, Jorge; Castro, Jonathan M.; Iroumé, Andrés; Andreoli, Andrea; Jones, Julia; Swanson, Fred; Crisafulli, Charlie

    2010-10-01

    High-silica rhyolite magma fuels Earth's largest and most explosive eruptions. Recurrence intervals for such highly explosive eruptions are in the 100- to 100,000­year time range, and there have been few direct observations of such eruptions and their immediate impacts. Consequently, there was keen interest within the volcanology community when the first large eruption of high-silica rhyolite since that of Alaska's Novarupta volcano in 1912 began on 1 May 2008 at Chaitén volcano, southern Chile, a 3-kilometer­diameter caldera volcano with a prehistoric record of rhyolite eruptions [Naranjo and Stern, 2004; Servicio Nacional de Geología y Minería (SERNAGEOMIN), 2008; Carn et al., 2009; Castro and Dingwell, 2009; Lara, 2009; Muñoz et al., 2009]. Vigorous explosions occurred through 8 May 2008, after which explosive activity waned and a new lava dome was extruded.

  12. Properties of Repetitive Long-Period Seismicity at Villarrica Volcano, Chile

    Science.gov (United States)

    Richardson, J.; Waite, G. P.; Palma, J.; Johnson, J. B.

    2011-12-01

    Villarrica Volcano, Chile hosts a persistent lava lake and is characterized by degassing and long-period seismicity. In order to better understand the relationship between outgassing and seismicity, we recorded broadband seismic and acoustic data along with high-rate SO2 emission data. We used both a densely-spaced linear array deployed on the northern flank of Villarrica, during the austral summer of 2011, and a wider aperture array of stations distributed around the volcano that was active in the austral summer of 2010. Both deployments consisted of three-component broadband stations and were augmented with broadband infrasound sensors. Of particular interests are repetitive, ~1 Hz seismic and coincident infrasound signals that occurred approximately every 2 minutes. Because these events are typically very low amplitude, we used a matched filter approach to identify them. We windowed several high-amplitude records of these events from broadband seismic stations near the vent. The record section of each event served as a template to compare with the entire dataset by cross-correlation. This approach identified ~20,000 nearly identical events during the ~7 day deployment of the linear array, which were otherwise difficult to identify in the raw records. Assuming that all of the events that we identified have identical source mechanisms and depths, we stack the large suite of events to produce low-noise records and particle motions at receivers farther than 5 km from the vent. We find that the records from stations near the edifice are dominated by tangential particle motion, suggesting the influence of near-field components. Correlation of these data with broadband acoustic data collected at the summit suggest that these repeatable seismic processes are linked to acoustic emissions, probably due to gas bubbles bursting at the magma free surface, as no eruptive products besides gas were being emitted by the volcano during the instrument deployment. The acoustic

  13. Volcano ecology at Chaiten, Chile: geophysical processes interact with forest ecosystems

    Science.gov (United States)

    Swanson, F. J.; Crisafulli, C.; Jones, J. A.; Lara, A.

    2010-12-01

    The May 2008 eruption of Chaiten Volcano (Chile) offers many insights into volcano ecology -ecological responses to volcanic and associated hydrologic processes and ecosystem development in post-eruption landscapes. Varied intensities of pyroclastic density currents (PDC) and thickness of tephra fall deposits (to 50+ cm) created strong gradients of disturbance in several hundred square kilometers of native forest in a sector north to southeast from the volcano. A gradient from tree removal to toppled forest to standing, scorched forest extends 1.5 km northward from the caldera rim along the trajectory of a PDC. Close to the vent (e.g., 2 km NE from rim) a rain of ca. 10 cm of gravel tephra stripped foliage and twigs from tree canopies; farther away (23 km SE) 10 cm of fine tephra loaded the canopy, causing extensive fall of limbs >8 cm diameter. Even in the severely disturbed, north-flank PDC zone, surviving bamboo, ferns, and other herbs sprouted from pre-eruption soil and other refugia; sprouts of new foliage appeared on the boles and major limbs of several species of toppled and scorched, standing trees; animals including vertebrates (rodents and amphibians) and terrestrial invertebrates (e.g., insects and arachnids) either survived or quickly recolonized; and a diverse fungal community began decomposing the vast dead wood resource. During the second growing season we documented the presence of some plant species that had colonized by seed. Within two years after the eruption secondary ecological disturbances resulting from channel change and overbank deposition of fluvially transported tephra created new patches of damaged forest in riparian zones of streams draining the north flank and along the Rio Rayas and Rio Chaiten. These features parallel observations in the intensively-studied, post-1980-eruption landscape of Mount St. Helens over a similar time period. However, several aspects of ecological response to the two eruptions differ because of differences

  14. Listening carefully. Unique observations of harmonic tremor at Lascar volcano, Chile

    Energy Technology Data Exchange (ETDEWEB)

    Hellweg, M. [Stuttgart Univ., Stuttgart (Germany). Inst. fuer Geophysik

    1999-06-01

    During the deployment of Proyecto de Investigacion Sismologica de la Cordillera Occidental 94 (PISCO '94) in the Atacama Desert of Northern Chile, a broadband seismic station and a network od three short-period three-component stations were installed around the active volcano Lascar (Chile). The paper analyzes the resulting data set, which include a sequence of harmonic tremor with a fundamental at a about 0.63 Hz and up to 30 overtones lasting 18 h. Power spectra and spectrograms of Lascar's harmonic tremor from the various stations demonstrate that the frequencies recorded cannot be explained as path effects, and must therefore be attributed to mechanisms at or near the source.

  15. Post-depositional fracturing and subsidence of pumice flow deposits: Lascar Volcano, Chile.

    Science.gov (United States)

    Whelley, Patrick L; Jay, J; Calder, E S; Pritchard, M E; Cassidy, N J; Alcaraz, S; Pavez, A

    Unconsolidated pyroclastic flow deposits of the 1993 eruption of Lascar Volcano, Chile, have, with time, become increasingly dissected by a network of deeply penetrating fractures. The fracture network comprises orthogonal sets of decimeter-wide linear voids that form a pseudo-polygonal grid visible on the deposit surface. In this work, we combine shallow surface geophysical imaging tools with remote sensing observations and direct field measurements of the deposit to investigate these fractures and their underlying causal mechanisms. Based on ground penetrating radar images, the fractures are observed to have propagated to depths of up to 10 m. In addition, orbiting radar interferometry shows that deposit subsidence of up to 1 cm/year -1 occurred between 1993 and 1996 with continued subsidence occurring at a slower rate thereafter. In situ measurements show that 1 m below the surface, the 1993 deposits remain 5°C to 15°C hotter, 18 years after emplacement, than adjacent deposits. Based on the observed subsidence as well as estimated cooling rates, the fractures are inferred to be the combined result of deaeration, thermal contraction, and sedimentary compaction in the months to years following deposition. Significant environmental factors, including regional earthquakes in 1995 and 2007, accelerated settling at punctuated moments in time. The spatially variable fracture pattern relates to surface slope and lithofacies variations as well as substrate lithology. Similar fractures have been reported in other ignimbrites but are generally exposed only in cross section and are often attributed to formation by external forces. Here we suggest that such interpretations should be invoked with caution, and deformation including post-emplacement subsidence and fracturing of loosely packed ash-rich deposits in the months to years post-emplacement is a process inherent in the settling of pyroclastic material.

  16. The Quaternary calc-alkaline volcanism of the Patagonian Andes close to the Chile triple junction: geochemistry and petrogenesis of volcanic rocks from the Cay and Maca volcanoes (˜45°S, Chile)

    Science.gov (United States)

    D'Orazio, M.; Innocenti, F.; Manetti, P.; Tamponi, M.; Tonarini, S.; González-Ferrán, O.; Lahsen, A.; Omarini, R.

    2003-08-01

    Major- and trace-element, Sr-Nd isotopes, and mineral chemistry data were obtained for a collection of volcanic rock samples erupted by the Cay and Maca Quaternary volcanoes, Patagonian Andes (˜45°S, Chile). Cay and Maca are two large, adjacent stratovolcanoes that rise from the Chiloe block at the southern end of the southern volcanic zone (SVZ) of the Andes. Samples from the two volcanoes are typical medium-K, calc-alkaline rocks that form two roughly continuous, largely overlapping series from subalkaline basalt to dacite. The overall geochemistry of the samples studied is very similar to that observed for most volcanoes from the southern SVZ. The narrow range of Sr-Nd isotope compositions ( 87Sr/ 86Sr=0.70389-0.70431 and 143Nd/ 144Nd=0.51277-0.51284) and the major- and trace-element distributions indicate that the Cay and Maca magmas differentiated by crystal fractionation without significant contribution by crustal contamination. This is in accordance with the thin (Maca magmas is investigated by means of the relative concentration of fluid mobile (e.g. Ba) and fluid immobile (e.g. Nb, Ta, Zr, Y) elements and other relevant trace-element ratios (e.g. Sr/Y). The results indicate that small amounts (Maca volcanoes and that, despite the very young age (Maca magma sources to the northern edge of the slab window generated by the subduction of the Chile ridge under the South American plate, we did not find any geochemical evidence for a contribution of a subslab asthenospheric mantle. However, this mantle has been used to explain the peculiar geochemical features (e.g. the mild alkalinity and relatively low ratios between large ion lithophile and high field strength elements) of the Hudson volcano, which is located even closer to the slab window than the Cay and Maca volcanoes are.

  17. Listening carefully: unique observations of harmonic tremor at Lascar volcano, Chile

    Directory of Open Access Journals (Sweden)

    M. Hellweg

    1999-06-01

    Full Text Available During the deployment of Proyecto de Investigación Sismológica de la Cordillera Occidental 94 (PISCO'94 in the Atacama Desert of Northern Chile, a broadband seismic station and a network of three short-period three-component stations were installed around the active volcano Lascar. The resulting data set includes a sequence of harmonic tremor with a fundamental at about 0.63 Hz and up to 30 overtones lasting 18 h. Power spectra and spectrograms of Lascar's harmonic tremor from the various stations demonstrate that the frequencies recorded cannot be explained as path effects, and must therefore be attributed to mechanisms at or near the source. The polarization of the wavefield cannot simply be explained as the propagation of any of the classical types of seismic waves, thus we apply new methods to the data to investigate the narrowband signals of the harmonic peaks. While the amplitude characteristics of these signals cannot be correlated across the network, frequency characteristics of the harmonic wavefield are consistent across stations and components. The tremor's fundamental frequency changes at the same time at all stations, indicating that such changes must be caused at the source. In addition, a change in the frequency of the fundamental, f1, is reflected exactly in the frequencies of the overtones, nf1 and peak-broadening in the power spectrum is the result of shifts in the fundamental frequency. It is therefore unlikely that the overtones are produced as resonances. This spectral behavior indicates rather that the source is some resonance at a single frequency within the magma, magma/gas or gas parts of the volcano whose amplitude exceeds the range for which the assumptions of linear acoustics are valid.

  18. Continuous monitoring of Hawaiian volcanoes with thermal cameras

    Science.gov (United States)

    Patrick, Matthew R.; Orr, Tim R.; Antolik, Loren; Lee, Robert Lopaka; Kamibayashi, Kevan P.

    2014-01-01

    Continuously operating thermal cameras are becoming more common around the world for volcano monitoring, and offer distinct advantages over conventional visual webcams for observing volcanic activity. Thermal cameras can sometimes “see” through volcanic fume that obscures views to visual webcams and the naked eye, and often provide a much clearer view of the extent of high temperature areas and activity levels. We describe a thermal camera network recently installed by the Hawaiian Volcano Observatory to monitor Kīlauea’s summit and east rift zone eruptions (at Halema‘uma‘u and Pu‘u ‘Ō‘ō craters, respectively) and to keep watch on Mauna Loa’s summit caldera. The cameras are long-wave, temperature-calibrated models protected in custom enclosures, and often positioned on crater rims close to active vents. Images are transmitted back to the observatory in real-time, and numerous Matlab scripts manage the data and provide automated analyses and alarms. The cameras have greatly improved HVO’s observations of surface eruptive activity, which includes highly dynamic lava lake activity at Halema‘uma‘u, major disruptions to Pu‘u ‘Ō‘ō crater and several fissure eruptions.

  19. Coupled geohazards at Southern Andes (Copahue-Lanín volcanoes): Chile's GEO supersite proposal

    Science.gov (United States)

    Lara, Luis E.; Cordova, Loreto

    2017-04-01

    volcanism (the so-called Red Nacional de Vigilancia Volcánica at Sernageomin) and tectonics (Centro Sismólogico Nacional at Universidad de Chile) allow a good complement with space-borne data (e.g., we observed deformation by GPS and InSAR at Villarrica volcano related to the March 3, 2015 eruption) in order to promote basic and applied research for a successful national strategy of disaster risk reduction. In addition, at least 3 active national research grants focus in this area and a number of young scientists are working there. Thus, we propose the Copahue-Lanín (37.5-39.5°S) segment of the Southern Volcanic Zone as a Geohazards Supersite and look forward for an enhanced engagement of the scientific community in this area.

  20. Rapid ascent of rhyolitic magma at Chaitén volcano, Chile.

    Science.gov (United States)

    Castro, Jonathan M; Dingwell, Donald B

    2009-10-08

    Rhyolite magma has fuelled some of the Earth's largest explosive volcanic eruptions. Our understanding of these events is incomplete, however, owing to the previous lack of directly observed eruptions. Chaitén volcano, in Chile's northern Patagonia, erupted rhyolite magma unexpectedly and explosively on 1 May 2008 (ref. 2). Chaitén residents felt earthquakes about 24 hours before ash fell in their town and the eruption escalated into a Plinian column. Although such brief seismic forewarning of a major explosive basaltic eruption has been documented, it is unprecedented for silicic magmas. As precursory volcanic unrest relates to magma migration from the storage region to the surface, the very short pre-eruptive warning at Chaitén probably reflects very rapid magma ascent through the sub-volcanic system. Here we present petrological and experimental data that indicate that the hydrous rhyolite magma at Chaitén ascended very rapidly, with velocities of the order of one metre per second. Such rapid ascent implies a transit time from storage depths greater than five kilometres to the near surface in about four hours. This result has implications for hazard mitigation because the rapidity of ascending rhyolite means that future eruptions may provide little warning.

  1. Magma evolution at Copahue volcano (Chile/Argentina border): insights from melt inclusions

    Science.gov (United States)

    Cannatelli, C.; Aracena, C.; Leisen, M.; Moncada, D.; Roulleau, E.; Vinet, N.; Petrelli, M.; Paolillo, A.; Barra, F.; Morata, D.

    2016-12-01

    Copahue volcano is an active stratovolcano in the Andean Southern Volcanic Zone (SVZ), straddling at the border between Central Chile and Argentina. The volcano's eruptive style during its history has changed from mainly effusive in the Pleistocene to explosive in the Holocene. The prehistoric eruptions can be divided into pre-glacial (PG), syn-glacial (SG) and post-glacial (PM) stages, with products ranging from basaltic andesites to andesites. In order to investigate the evolution of the magma source and volatiles through time, we have focused our study on the eruptive products from the SG to the 2014 eruption (SUM2014). Sampled rocks are glomero-porphyritic, with a paragenetic mineral sequence of feldspars, ortho- and clinopyroxene, and olivine in order of abundance. All samples present a variable number of vesicles, with SUM2014 samples containing the biggest amount. Feldspar composition varies from Na-rich (andesine) in SG to Ca-rich (labradorite) in SUM2014. Two pyroxene types are present in SG and PM samples (augite and enstatite), while SUM2014 presents augite, pigeonite and enstatite. Thermobarometric estimation, based on mineral chemistry, show a bimodal distribution for SG and SUM2014 (P=10-12 kbars and 5-8 kbars) and only one interval for PM (P=7-8 kbars). Melt Inclusions Assemblages (MIAs) are found in all mineral phases, mostly re-crystallized, with one or more bubbles and daughter oxide minerals. Compositions vary from trachy-andesitic to dacitic for SG, andesitic to trachydacitic for PM, and basaltic andesitic to trachydacitic for SUM2014. Major elements systematics show the existence of a bimodal distribution of pyroxene and feldspar hosted-MIA in SUM2014, which together with the co-presence of pigeonite (low-Ca pyroxene) and augite and the bimodal distribution of P, can be interpreted as evidence of mixing of two types of magmas, evolving at different depths. Trace elements systematics for MIA in SG, PM and SUM2014 show a negative anomaly for Nb

  2. Long-range volcanic ash transport and fallout during the 2008 eruption of Chaiten volcano, Chile

    Science.gov (United States)

    Durant, A. J.; Prata, A. J.; Villarosa, G.; Rose, W. I.; Delmelle, P.; Viramonte, J.

    2012-04-01

    The May 2008 eruption of Chaitén volcano, Chile, provided a rare opportunity to measure the long-range transport of volcanic emissions and characteristics of a widely-dispersed terrestrial ash deposit. Airborne ash mass, quantified using thermal infrared satellite remote sensing, ranged between 0.2-0.4 Tg during the period 3-7 May 2008. A high level of spatiotemporal correspondence was observed between cloud trajectories and changes in surface reflectivity, which was inferred to indicate ash deposition. The evolution of the deposit was mapped for the first time using satellite-based observations of surface reflectivity. The distal (>80 km) ash deposit was poorly sorted and fine grained, and mean particle size varied very little beyond a distance >300 km. There were 3 consistent particle size subpopulations in fallout at distances >300 km which suggests that aggregation influenced particle settling. Discrete temporal sampling and characterisation of fallout demonstrated contributions from specific eruptive phases. Some evidence for winnowing was identified through comparison of samples collected at the time of deposition to bulk samples collected months after deposition. X-Ray Photoelectron Spectroscopy (XPS) analyses revealed surface enrichments in Ca, Na and Fe and the presence of coatings of mixed Ca-, Na- and Fe-rich salts on ash particles prior to deposition. XPS analyses revealed strong surface Fe enrichments (in contrast to the results from bulk leachate analyses), which indicates that surface analysis techniques should be applied to investigate potential influences on ocean productivity in response to volcanic ash fallout over oceans. Low S:Cl ratios in leachates indicate that the eruption had a low S content, and high Cl:F ratios imply gas-ash interaction within a Cl-rich environment. We estimate that ash fallout had potential to scavenge ~42 % of total S released into the atmosphere prior to deposition.

  3. Volcanoes

    Science.gov (United States)

    ... rock, steam, poisonous gases, and ash reach the Earth's surface when a volcano erupts. An eruption can also cause earthquakes, mudflows and flash floods, rock falls and landslides, acid rain, fires, and even tsunamis. Volcanic gas ...

  4. Volcanic lightning and plume behavior reveal evolving hazards during the April 2015 eruption of Calbuco volcano, Chile

    Science.gov (United States)

    Van Eaton, Alexa; Amigo, Álvaro; Bertin, Daniel; Mastin, Larry G.; Giacosa, Raúl E; González, Jerónimo; Valderrama, Oscar; Fontijn, Karen; Behnke, Sonja A

    2016-01-01

    Soon after the onset of an eruption, model forecasts of ash dispersal are used to mitigate the hazards to aircraft, infrastructure and communities downwind. However, it is a significant challenge to constrain the model inputs during an evolving eruption. Here we demonstrate that volcanic lightning may be used in tandem with satellite detection to recognize and quantify changes in eruption style and intensity. Using the eruption of Calbuco volcano in southern Chile on 22-23 April 2015, we investigate rates of umbrella cloud expansion from satellite observations, occurrence of lightning, and mapped characteristics of the fall deposits. Our remote-sensing analysis gives a total erupted volume that is within uncertainty of the mapped volume (0.56 ±0.28 km3 bulk). Observations and volcanic plume modeling further suggest that electrical activity was enhanced both by ice formation in the ash clouds >10 km asl and development of a low-level charge layer from ground-hugging currents.

  5. A study of SO2 emissions and ground surface displacements at Lastarria volcano, Antofagasta Region, Northern Chile

    Science.gov (United States)

    Krewcun, Lucie G.

    Lastarria volcano (Chile) is located at the North-West margin of the 'Lazufre' ground inflation signal (37x45 km2), constantly uplifting at a rate of ˜2.5 cm/year since 1996 (Pritchard and Simons 2002; Froger et al. 2007). The Lastarria volcano has the double interest to be superimposed on a second, smaller-scale inflation signal and to be the only degassing area of the Lazufre signal. In this project, we compared daily SO2 burdens recorded by AURA's OMI mission for 2005-2010 with Ground Surface Displacements (GSD) calculated from the Advanced Synthetic Aperture Radar (ASAR) images for 2003-2010. We found a constant maximum displacement rate of 2.44 cm/year for the period 2003-2007 and 0.80- 0.95 cm/year for the period 2007-2010. Total SO 2 emitted is 67.0 kT for the period 2005-2010, but detection of weak SO2 degassing signals in the Andes remains challenging owing to increased noise in the South Atlantic radiation Anomaly region.

  6. Origin of fumarolic fluids from Tupungatito Volcano (Central Chile): interplay between magmatic, hydrothermal, and shallow meteoric sources

    Science.gov (United States)

    Benavente, Oscar; Tassi, Franco; Gutiérrez, Francisco; Vaselli, Orlando; Aguilera, Felipe; Reich, Martin

    2013-08-01

    Tupungatito is a poorly known volcano located about 100 km eastward of Santiago (Chile) in the northernmost sector of the South Volcanic Zone. This 5,682 m high volcano shows intense fumarolic activity. It hosts three crater lakes within the northwestern portion of the summit area. Chemical compositions of fumarolic gases and isotopic signatures of noble gases (3He/4He and 40Ar/36Ar are up to 6.09 Ra and 461, respectively), and steam (δ18O and δD) suggest that they are produced by mixing of fluids from a magmatic source rich in acidic gas compounds (SO2, HCl, and HF), and meteoric water. The magmatic-hydrothermal fluids are affected by steam condensation that controls the outlet fumarolic temperatures (contamination from the subducting slab, (2) the sedimentary basement, and (3) limited contribution from crustal sediments. Gas geothermometry based on the kinetically rapid H2-CO equilibria indicates equilibrium temperatures 200 °C and redox conditions are consistent with those inferred by the presence of the SO2-H2S redox pair, typical of fluids that have attained equilibrium in magmatic environment. A comprehensive conceptual geochemical model describing the circulation pattern of the Tupungatito hydrothermal-magmatic fluids is proposed. It includes fluid source regions and re-equilibration processes affecting the different gas species due to changing chemical-physical conditions as the magmatic-hydrothermal fluids rise up toward the surface.

  7. Chile.

    Science.gov (United States)

    1992-05-01

    The background notes on Chile provide a statistical summary of the population, geography, government, and the economy, and more descriptive text on the history, population, government, economy, defense, and foreign relations. In brief, Chile has 13.3 million Spanish Indian (Mestizos), European, and Indian inhabitants and an annual growth rate of 1.6%. 96% are literate. Infant mortality is 18/1000. 34% of the population are involved in industry and commerce, 30% in services, 19% in agriculture and forestry and fishing, 7% in construction, and 2% in mining. The major city is Santiago. The government, which gained independence in 1810, is a republic with executive, legislative, and judicial branches. There are 12 regions. There are 6 major political parties. Suffrage is universal at 18 years. Gross domestic product (GDP) is $29.2 billion. The annual growth rate is 5% and inflation is 19%. Copper, timber, fish, iron ore, nitrates, precious metals, and molybdenum are its natural resources. Agricultural products are 9% of GDP and include wheat, potatoes, corn, sugar beets, onions, beans, fruits, and livestock. Industry is 21% of GDP and includes mineral refining, metal manufacturing, food and fish processing, paper and wood products, and finished textiles. $8.3 billion is the value of exports and $7 billion of imports. Export markets are in Japan, the US, Germany, Brazil, and the United Kingdom. Chile received $3.5 billion in economic aid between 1949-85, but little in recent years. 83% live in urban centers, principally around Santiago. Congressional representation is made on the basis of elections by a unique binomial majority system. Principal government officials are identified. Chile has a diversified free market economy and is almost self-sufficient in food production. The US is a primary trading partner. 49% of Chile's exports are minerals. Chile maintains diplomatic relations with 70 countries, however, relations are strained with Argentina and Bolivia. Relations

  8. Chile.

    Science.gov (United States)

    1988-09-01

    Chile is a long (2650 miles), narrow (250 miles at widest point) country sandwiched between the Andes mountains and the Pacific. The northern desert is rich in copper and nitrates; the temperate middle region is agricultural and supports the major cities, including Santiago, the capital, and the port of Valparaiso; and the southern region is a cold and damp area of forests, grasslands, lakes, and fjords. The country is divided into 12 administrative regions. Chile's population of 12.5 million are mainly of Spanish or Indian descent or mestizos. Literacy is 92.3%, and the national language is Spanish. Infant mortality is 18.1/1000, and life expectancy is 68.2 years. 82% of the people are urban, and most are Roman Catholics. Chile was settled by the Spanish in 1541 and attached to the Viceroyalty of Peru. Independence was won in 1818 under the leadership of Bernardo O'Higgins. In the 1880s Chile extended its sovereignty over the Strait of Magellan in the south and areas of southern Peru and Bolivia in the north. An officially parliamentary government, elected by universal suffrage, drifted into oligarchy and finally into a military dictatorship under Carlos Ibanez in 1924. Constitutional government was restored in 1932. The Christian Democratic government of Eduardo Frei (1964-70) inaugurated major reforms, including land redistribution, education, and far-reaching social and economic policies. A Marxist government under Salvador Allende lasted from 1970 to 1973 when the present military government of General Pinochet Ugarte took power, overthrew Allende, abolished the Congress, and banned political parties. It has moved the country in the direction of a free market economy but at the cost of systematic violations of human rights. A new constitution was promulgated in 1981, and congressional elections have been scheduled for October, 1989. A "National Accord for Transition to Full Democracy" was mediated by the Catholic Church in 1985. The social reforms of the

  9. A remote sensing assessment of the impact of the 2010 Maule, Chile earthquake (Mw 8.8) on the volcanoes of the southern Andes

    Science.gov (United States)

    Pritchard, M. E.; Welch, M.; Jay, J.; Button, N.

    2011-12-01

    There are tantalizing, but controversial, indications that great earthquakes affect arc-wide volcanic activity. For example, analysis of historic eruptions at volcanoes of the southern Andes has shown that 3-4 eruptions were likely seismically triggered by Mw > 8 earthquakes in the Chile subduction zone -- particularly the 1906 and 1960 earthquakes (e.g., Watt et al., 2009). However, the 27 February 2010 Mw 8.8 Maule, Chile earthquake that ruptured the subduction zone between the 1960 and 1906 earthquakes does not appear to have triggered 3-4 volcanic eruptions in the same area in the 12 months after the event. In an effort to understand the relation between a large earthquake and volcanic unrest, we use a variety of satellite instruments to look for more subtle (i.e., not leading to eruption), but detectable change in thermal or deformation activity at the volcanoes of the southern Andes after the Maule earthquake and its aftershocks. For all of the volcanoes in the catalog of the Smithsonian Institution (approximately 80), we use nighttime MODIS and ASTER data to assess the thermal activity and ALOS InSAR data to characterize the surface deformation before and after the earthquake. The ALOS InSAR data are not ideal for detecting changes in deformation before and after the earthquake because of the small number of acquisitions in austral summer as well as ionospheric and tropospheric artifacts. We estimate that we could detect deformation > 5 cm/year. Similarly, the ASTER and MODIS data suffer respectively from poor temporal and spatial resolution of thermal anomalies. We update previous InSAR work that identified at least 8 areas of volcanic deformation in the southern Andes related to eruptive processes, subsidence of past lava flows, or surface uplift not associated with an eruption (Fournier et al., 2010). Of greatest interest are the two volcanic areas with the largest deformation signals between 2007-2008 (both > 15 cm/yr in the radar line of sight): Laguna

  10. Late Pleistocene to Holocene tephrostratigraphy of the Lonquimay Volcano, South Central Chile

    Science.gov (United States)

    Gilbert, D.; Freundt, A.; Kutterolf, S.; Burkert, C.

    2010-12-01

    The Lonquimay Volcanic Complex (LVC) in South Central Chile (38.38°S, 71.58°W) is part of the Southern Volcanic Zone of the Andes, which formed in response to the subduction of the Nazca Plate beneath the South American Plate. During the course of its magmatic evolution, the LVC produced explosive eruptions documented in the succession of widespread tephra deposits, as well as large lava flows that originated from the main edifice and several adjacent minor eruptive centers. The last eruptive phase in Lonquimays volcanic evolution occurred from 1988-1990. It led to the formation of the Navidad cinder cone with its associated 10.2 km long lava flow, and a widely distributed tephra blanket of andesitic composition (Moreno and Gardeweg, 1989). During recent field work we reinvestigated and complemented the LVC tephrostratigraphy as originally established by Polanco (1998)by detailed logging of 22 outcrops and collecting 126 stratigraphically controlled samples that were analyzed for their matrix glass, mineral and bulk rock compositions. This data set allows us to verify and extend the field-based correlations, and to establish a tephrostratigraphy for the LVC that comprises 15 stratigraphic units (LQA-LQO) and provides a framework for ongoing investigations of the petrogenetic evolution of the LVC. The stratigraphic record identifies at least 13 explosive eruptions of VEI > 3 that occurred since the last glaciation period (17150 a BP, McCulloch et al. 2000). Magmatic compositions of the tephra deposits range from basaltic scoriae (51wt% SiO2) to evolved dacitic pumice lapilli layers (67wt% SiO2), and thus have a wider compositional range than the chemically distinct andesitic lavas (57-63wt%) of the LVC. The vertical succession of tephra compositions reflects four periods of progressive magmatic differentiation, each successively tapped by several eruptions. The maximum degree of fractionation reached during these periods increases to younger ages. The

  11. Spatial analysis of the impacts of the Chaitén volcano eruption (Chile) in three fluvial systems

    Science.gov (United States)

    Ulloa, H.; Iroumé, A.; Picco, L.; Mohr, C. H.; Mazzorana, B.; Lenzi, M. A.; Mao, L.

    2016-08-01

    The eruption of the Chaitén volcano in May 2008 generated morphological and ecological disturbances in adjacent river basins, and the magnitude of these disturbances depended on the type of dominant volcanic process affecting each of them. The aim of this study is to analyse the morphological changes in different periods in river segments of the Blanco, El Amarillo and Rayas river basins located near the Chaitén volcano. These basins suffered disturbances of different intensity and spatial distribution caused by tephra fall, dome collapses and pyroclastic density currents that damaged hillslope forests, widened channels and destroyed island and floodplain vegetation. Changes continued to occur in the fluvial systems in the years following the eruption, as a consequence of the geomorphic processes indirectly induced by the eruption. Channel changes were analyzed by comparing remote images of pre and post-eruption conditions. Two periods were considered: the first from 2008 to 2009-2010 associated with the explosive and effusive phases of the eruption and the second that correspond to the post-eruption stage from 2009-2010 to 2013. Following the first phases channel segments widened 91% (38 m/yr), 6% (7 m/yr) and 7% (22 m/yr) for Blanco, Rayas and El Amarillo Rivers, respectively, compared to pre-eruption condition. In the second period, channel segments additionally widened 42% (8 m/yr), 2% (2 m/yr) and 5% (4 m/yr) for Blanco, Rayas and El Amarillo Rivers, respectively. In the Blanco River 62 and 82% of the islands disappeared in the first and second period, respectively, which is 6-8 times higher than in the El Amarillo approximately twice the Rayas. Sinuosity increased after the eruption only in the Blanco River but the three study channels showed a high braiding intensity mainly during the first post-eruption period. The major disturbances occurred during the eruptive and effusive phases of Chaitén volcano, and the intensity of these disturbances reflects the

  12. January 30, 1997 eruptive event on Kilauea Volcano, Hawaii, as monitored by continuous GPS

    Science.gov (United States)

    Owen, S.; Segall, P.; Lisowski, M.; Miklius, Asta; Murray, M.; Bevis, M.; Foster, J.

    2000-01-01

    A continuous Global Positioning System (GPS) network on Kilauea Volcano captured the most recent fissure eruption in Kilauea's East Rift Zone (ERZ) in unprecedented spatial and temporal detail. The short eruption drained the lava pond at Pu'u O' o, leading to a two month long pause in its on-going eruption. Models of the GPS data indicate that the intrusion's bottom edge extended to only 2.4 km. Continuous GPS data reveal rift opening 8 hours prior to the eruption. Absence of precursory summit inflation rules out magma storage overpressurization as the eruption's cause. We infer that stresses in the shallow rift created by the continued deep rift dilation and slip on the south flank decollement caused the rift intrusion.

  13. Volcano Monitoring in Ecuador: Three Decades of Continuous Progress of the Instituto Geofisico - Escuela Politecnica Nacional

    Science.gov (United States)

    Ruiz, M. C.; Yepes, H. A.; Hall, M. L.; Mothes, P. A.; Ramon, P.; Hidalgo, S.; Andrade, D.; Vallejo Vargas, S.; Steele, A. L.; Anzieta, J. C.; Ortiz, H. D.; Palacios, P.; Alvarado, A. P.; Enriquez, W.; Vasconez, F.; Vaca, M.; Arrais, S.; Viracucha, G.; Bernard, B.

    2014-12-01

    In 1988, the Instituto Geofisico (IG) began a permanent surveillance of Ecuadorian volcanoes, and due to activity on Guagua Pichincha, SP seismic stations and EDM control lines were then installed. Later, with the UNDRO and OAS projects, telemetered seismic monitoring was expanded to Tungurahua, Cotopaxi, Cuicocha, Chimborazo, Antisana, Cayambe, Cerro Negro, and Quilotoa volcanoes. In 1992 an agreement with the Instituto Ecuatoriano de Electrificacion strengthened the monitoring of Tungurahua and Cotopaxi volcanoes with real-time SP seismic networks and EDM lines. Thus, background activity levels became established, which was helpful because of the onset of the 1999 eruptive activity at Tungurahua and Guagua Pichincha. These eruptions had a notable impact on Baños and Quito. Unrest at Cotopaxi volcano was detected in 2001-2002, but waned. In 2002 Reventador began its eruptive period which continues to the present and is closely monitored by the IG. In 2006 permanent seismic BB stations and infrasound sensors were installed at Tungurahua and Cotopaxi under a cooperative program supported by JICA, which allowed us to follow Tungurahua's climatic eruptions of 2006 and subsequent eruptions up to the present. Programs supported by the Ecuadorian Secretaria Nacional de Ciencia y Tecnologia and the Secretaria Nacional de Planificacion resulted in further expansion of the IG's monitoring infrastructure. Thermal and video imagery, SO2 emission monitoring, geochemical analyses, continuous GPS and tiltmeters, and micro-barometric surveillance have been incorporated. Sangay, Soche, Ninahuilca, Pululahua, and Fernandina, Cerro Azul, Sierra Negra, and Alcedo in the Galapagos Islands are now monitored in real-time. During this time, international cooperation with universities (Blaise Pascal & Nice-France, U. North Carolina, New Mexico Tech, Uppsala-Sweden, Nagoya, etc.), and research centers (USGS & UNAVCO-USA, IRD-France, NIED-Japan, SGC-Colombia, VAAC, MIROVA) has introduced

  14. Exceptional mobility of an advancing rhyolitic obsidian flow at Cordón Caulle volcano in Chile.

    Science.gov (United States)

    Tuffen, Hugh; James, Mike R; Castro, Jonathan M; Schipper, C Ian

    2013-01-01

    The emplacement mechanisms of rhyolitic lava flows are enigmatic and, despite high lava viscosities and low inferred effusion rates, can result in remarkably, laterally extensive (>30 km) flow fields. Here we present the first observations of an active, extensive rhyolitic lava flow field from the 2011-2012 eruption at Cordón Caulle, Chile. We combine high-resolution four-dimensional flow front models, created using automated photo reconstruction techniques, with sequential satellite imagery. Late-stage evolution greatly extended the compound lava flow field, with localized extrusion from stalled, ~35 m-thick flow margins creating >80 breakout lobes. In January 2013, flow front advance continued ~3.6 km from the vent, despite detectable lava supply ceasing 6-8 months earlier. This illustrates how efficient thermal insulation by the lava carapace promotes prolonged within-flow horizontal lava transport, boosting the extent of the flow. The unexpected similarities with compound basaltic lava flow fields point towards a unifying model of lava emplacement.

  15. Decoupling of soil development and plant succession along a 60000 years chronosequence in Llaima Volcano, Chile Desacoplamiento del desarrollo del suelo y la sucesión vegetal a lo largo de una cronosecuencia de 60 mil años en el volcán Llaima, Chile

    OpenAIRE

    MARÍA-BELÉN GALLARDO; CECILIA PÉREZ; MARIELA NÚÑEZ-ÁVILA; JUAN J. ARMESTO

    2012-01-01

    Few studies have investigated the long-term evolution of nutrient limitation in ecosystems developed on volcanic soils. To approach the problem, we used "space for time substitution" to compare sites with the same state factors, except for the time elapsed since disturbance. Forests of Conguillio National Park in southern of Chile occur on volcanic soils that developed from lava flows and ash deposits of different ages originated from the activity of Llaima volcano. In this study we evaluate ...

  16. A contribution to the hazards assessment at Copahue volcano (Argentina-Chile) by facies analysis of a recent pyroclastic density current deposit

    Science.gov (United States)

    Balbis, C.; Petrinovic, I. A.; Guzmán, S.

    2016-11-01

    We recognised and interpreted a recent pyroclastic density current (PDC) deposit at the Copahue volcano (Southern Andes), through a field survey and a sedimentological study. The relationships between the behaviour of the PDCs, the morphology of the Río Agrio valley and the eruptive dynamics were interpreted. We identified two lithofacies in the deposit that indicate variations in the eruptive dynamics: i) the opening of the conduit and the formation of a highly explosive eruption that formed a diluted PDC through the immediate collapse of the eruptive column; ii) a continued eruption which followed immediately and records the widening of the conduit, producing a dense PDC. The eruption occurred in 2000 CE, was phreatomagmatic (VEI ≤ 2), with a vesiculation level above 4000 m depth and fragmentation driven by the interaction of magma with an hydrothermal system at ca. 1500 m depth. As deduced from the comparison between the accessory lithics of this deposit and those of the 2012 CE eruption, the depth of onset of vesiculation and fragmentation level in this volcano is constant in depth. In order to reproduce the distribution pattern of this PDC's deposit and to simulate potential PDC's forming-processes, we made several computational modelling from "denser" to "more diluted" conditions. The latter fairly reproduces the distribution of the studied deposit and represents perhaps one of the most dangerous possible scenarios of the Copahue volcanic activity. PDCs occurrence has been considered in the last volcanic hazards map as a low probability process; evidences found in this contribution suggest instead to include them as more probable and thus very important for the hazards assessment of the Copahue volcano.

  17. Modeling continuous seismic velocity changes due to ground shaking in Chile

    Science.gov (United States)

    Gassenmeier, Martina; Richter, Tom; Sens-Schönfelder, Christoph; Korn, Michael; Tilmann, Frederik

    2015-04-01

    In order to investigate temporal seismic velocity changes due to earthquake related processes and environmental forcing, we analyze 8 years of ambient seismic noise recorded by the Integrated Plate Boundary Observatory Chile (IPOC) network in northern Chile between 18° and 25° S. The Mw 7.7 Tocopilla earthquake in 2007 and the Mw 8.1 Iquique earthquake in 2014 as well as numerous smaller events occurred in this area. By autocorrelation of the ambient seismic noise field, approximations of the Green's functions are retrieved. The recovered function represents backscattered or multiply scattered energy from the immediate neighborhood of the station. To detect relative changes of the seismic velocities we apply the stretching method, which compares individual autocorrelation functions to stretched or compressed versions of a long term averaged reference autocorrelation function. We use time windows in the coda of the autocorrelations, that contain scattered waves which are highly sensitive to minute changes in the velocity. At station PATCX we observe seasonal changes in seismic velocity as well as temporary velocity reductions in the frequency range of 4-6 Hz. The seasonal changes can be attributed to thermal stress changes in the subsurface related to variations of the atmospheric temperature. This effect can be modeled well by a sine curve and is subtracted for further analysis of short term variations. Temporary velocity reductions occur at the time of ground shaking usually caused by earthquakes and are followed by a recovery. We present an empirical model that describes the seismic velocity variations based on continuous observations of the local ground acceleration. Our hypothesis is that not only the shaking of earthquakes provokes velocity drops, but any small vibrations continuously induce minor velocity variations that are immediately compensated by healing in the steady state. We show that the shaking effect is accumulated over time and best described by

  18. Resistivity variations related to the large March 9, 1998 eruption at La Fournaise volcano inferred by continuous MT monitoring

    Science.gov (United States)

    Wawrzyniak, Pierre; Zlotnicki, Jacques; Sailhac, Pascal; Marquis, Guy

    2017-11-01

    The 2645 m-high La Fournaise volcano, located in the Southwest of Réunion Island (Indian Ocean), is a shield basaltic volcano where effusive eruptions generally occur along long fissures starting from the summit, alongside major fractures that characterize the eruptions' dynamism and effusivity. Between 1992 and 1998, the volcano underwent a quiet period during which few earthquakes were recorded. Minor seismic activity returned after 1997 and picked up in March 1998 during the 35 h preceding the March 9 eruption. From 1996, two autonomous stations (CSV and BAV) were installed on the volcano. CSV was located inside the Enclos Fouqué caldera while BAV was positioned 8.2 km NW of the volcano summit. Horizontal components of the electric and magnetic fields were sampled every 20 s. Continuous time-series were available from 1996 to 1999 at CSV, and from 1997 to March 1998 at BAV. Data have been processed using both single-station and remote-reference processing. Both results show apparent resistivity variations synchronous to the eruption. Time-lapse impedance estimates are computed on overlapping time windows of about two days at both stations. The only major decrease of the observed impedance coincides with the March 1998 eruption. At CSV, the resistivity started to drop about five days before the eruption, reached several local minima until April, and then slowly increased as the volcanic crisis reduced in activity. After the end of the crisis in September 1998, the apparent resistivity recovered its pre-crisis value. The time-lapse results also show variability in directionality: sharp and elongated phase tensor ellipse residuals appear during the eruption with a N105° orientation, suggesting the emergence of an almost NS-striking dyke. A 1D background model built from MT soundings performed during the quiet period (1996 to February 1998) on which a 3D NS-striking dyke was added shows a good agreement with phase tensor residuals and spatial distribution of the

  19. Development of an Infrared Remote Sensing System for Continuous Monitoring of Stromboli Volcano

    Science.gov (United States)

    Harig, R.; Burton, M.; Rausch, P.; Jordan, M.; Gorgas, J.; Gerhard, J.

    2009-04-01

    In order to monitor gases emitted by Stromboli volcano in the Eolian archipelago, Italy, a remote sensing system based on Fourier-transform infrared spectroscopy has been developed and installed on the summit of Stromboli volcano. Hot rocks and lava are used as sources of infrared radiation. The system is based on an interferometer with a single detector element in combination with an azimuth-elevation scanning mirror system. The mirror system is used to align the field of view of the instrument. In addition, the system is equipped with an infrared camera. Two basic modes of operation have been implemented: The user may use the infrared image to align the system to a vent that is to be examined. In addition, the scanning system may be used for (hyperspectral) imaging of the scene. In this mode, the scanning mirror is set sequentially move to all positions within a region of interest which is defined by the operator using the image generated from the infrared camera. The spectral range used for the measurements is 1600 - 4200 cm-1 allowing the quantification of many gases such as CO, CO2, SO2, and HCl. The spectral resolution is 0.5 cm-1. In order to protect the optical, mechanical and electrical parts of the system from the volcanic gases, all components are contained in a gas-tight aluminium housing. The system is controlled via TCP/IP (data transfer by WLAN), allowing the user to operate it from a remote PC. The infrared image of the scene and measured spectra are transferred to and displayed by a remote PC at INGV or TUHH in real-time. However, the system is capable of autonomous operation on the volcano, once a measurement has been started. Measurements are stored by an internal embedded PC.

  20. Location and wavefield attributes of long-period signals at Villarrica volcano (Chile) determined by array and polarization-moveout analysis

    Science.gov (United States)

    Lehr, Johanna; Thorwart, Martin; Rabbel, Wolfgang

    2016-04-01

    Villarrica Volcano is the most active volcano in Chile whose latest eruption occurred in March 2015. Increasing the knowledge on its processes, structure and behavior is thus crucial to an effective monitoring and hazard assessment. In this context, long-period volcanic signals (LP) are considered to be a key to the understanding of fluid dynamics and volcanic plumbing systems, accessible by seismological observations. However, standard seismological location tools usually fail due to the emergent onset of the signal and its serious distortion caused by attenuation and scattering in a complex geology. Therefore, alternative methods are needed. In March 2012, a dense seismic network was installed at Villarrica for two weeks with 50 stations covering the volcanic edifice including 6 subarrays. About 400 LP events were identified. LP-events recorded on crater stations look similar to typical earthquakes arrivals with distinguishable P- and S-wave onsets indicating a source near the crater. But with increasing source distance waveforms gradually change into typical LP-events. To investigate how to locate these LP-events we tested two approaches at the basis of a show-case event. In a first trial, records of the subarrays were used to determine backazimuths and slowness by beamforming in the time domain. The analysis was performed in a moving window, using semblance to measure the beam quality. The epicenter was derived by intersecting azimuthal rays. It locates ca. 1 km southeast of the summit crater. Slownesses range from 0.5 s/km up to 2.0 s/km. At frequencies above 2 Hz, additional maxima appear in the semblance distribution of near-summit arrays which can be interpreted as side-scattered signals. Since the crossing points of the backazimuth rays showed some scattering we tested polarization analysis (applied to the subset of 3-component stations) as an alternative location method. Although the direct interpretation of the backazimuths was unreliable, we identified

  1. Continuous gravity measurements reveal a low-density lava lake at Kīlauea Volcano, Hawai‘i

    Science.gov (United States)

    Carbone, Daniele; Poland, Michael P.; Patrick, Matthew R.; Orr, Tim R.

    2013-01-01

    On 5 March 2011, the lava lake within the summit eruptive vent at Kīlauea Volcano, Hawai‘i, began to drain as magma withdrew to feed a dike intrusion and fissure eruption on the volcanoʼs east rift zone. The draining was monitored by a variety of continuous geological and geophysical measurements, including deformation, thermal and visual imagery, and gravity. Over the first ∼14 hours of the draining, the ground near the eruptive vent subsided by about 0.15 m, gravity dropped by more than 100 μGal, and the lava lake retreated by over 120 m. We used GPS data to correct the gravity signal for the effects of subsurface mass loss and vertical deformation in order to isolate the change in gravity due to draining of the lava lake alone. Using a model of the eruptive vent geometry based on visual observations and the lava level over time determined from thermal camera data, we calculated the best-fit lava density to the observed gravity decrease — to our knowledge, the first geophysical determination of the density of a lava lake anywhere in the world. Our result, 950 +/- 300 kg m-3, suggests a lava density less than that of water and indicates that Kīlaueaʼs lava lake is gas-rich, which can explain why rockfalls that impact the lake trigger small explosions. Knowledge of such a fundamental material property as density is also critical to investigations of lava-lake convection and degassing and can inform calculations of pressure change in the subsurface magma plumbing system.

  2. An automated SO2 camera system for continuous, real-time monitoring of gas emissions from Kīlauea Volcano's summit Overlook Crater

    Science.gov (United States)

    Kern, Christoph; Sutton, Jeff; Elias, Tamar; Lee, Robert Lopaka; Kamibayashi, Kevan P.; Antolik, Loren; Werner, Cynthia A.

    2015-01-01

    SO2 camera systems allow rapid two-dimensional imaging of sulfur dioxide (SO2) emitted from volcanic vents. Here, we describe the development of an SO2 camera system specifically designed for semi-permanent field installation and continuous use. The integration of innovative but largely “off-the-shelf” components allowed us to assemble a robust and highly customizable instrument capable of continuous, long-term deployment at Kīlauea Volcano's summit Overlook Crater. Recorded imagery is telemetered to the USGS Hawaiian Volcano Observatory (HVO) where a novel automatic retrieval algorithm derives SO2 column densities and emission rates in real-time. Imagery and corresponding emission rates displayed in the HVO operations center and on the internal observatory website provide HVO staff with useful information for assessing the volcano's current activity. The ever-growing archive of continuous imagery and high-resolution emission rates in combination with continuous data from other monitoring techniques provides insight into shallow volcanic processes occurring at the Overlook Crater. An exemplary dataset from September 2013 is discussed in which a variation in the efficiency of shallow circulation and convection, the processes that transport volatile-rich magma to the surface of the summit lava lake, appears to have caused two distinctly different phases of lake activity and degassing. This first successful deployment of an SO2 camera for continuous, real-time volcano monitoring shows how this versatile technique might soon be adapted and applied to monitor SO2 degassing at other volcanoes around the world.

  3. A New, Continuous 5400 Yr-long Paleotsunami Record from Lake Huelde, Chiloe Island, South Central Chile.

    Science.gov (United States)

    Kempf, P.; Moernaut, J.; Vandoorne, W.; Van Daele, M. E.; Pino, M.; Urrutia, R.; De Batist, M. A. O.

    2014-12-01

    After the last decade of extreme tsunami events with catastrophic damage to infrastructure and a horrendous amount of casualties, it is clear that more and better paleotsunami records are needed to improve our understanding of the recurrence intervals and intensities of large-scale tsunamis. Coastal lakes (e.g. Bradley Lake, Cascadia; Kelsey et al., 2005) have the potential to contain long and continuous sedimentary records, which is an important asset in view of the centennial- to millennial-scale recurrence times of great tsunami-triggering earthquakes. Lake Huelde on Chiloé Island (42.5°S), Chile, is a coastal lake located in the middle of the Valdivia segment, which is known for having produced the strongest ever instrumentally recorded earthquake in 1960 AD (MW: 9.5), and other large earthquakes prior to that: i.e. 1837 AD, 1737 AD (no report of a tsunami) and 1575 AD (Lomnitz, 1970, 2004, Cisternas et al., 2005). We present a new 5400 yr-long paleotsunami record with a Bayesian age-depth model based on 23 radiocarbon dates that exceeds all previous paleotsunami records from the Valdivia segment, both in terms of length and of continuity. 18 events are described and a semi-quantitative measure of the event intensity at the study area is given, revealing at least two predecessors of the 1960 AD event in the mid to late Holocene that are equal in intensity. The resulting implications from the age-depth model and from the semi-quantitative intensity reconstruction are discussed in this contribution.

  4. Seismicity preliminary results in a geothermal and volcano activity area: study case Liquiñe-Ofqui fault system in Southern Andes, Chile

    Science.gov (United States)

    Estay, N. P.; Yáñez Morroni, G.; Crempien, J. G. F.; Roquer, T.

    2017-12-01

    Fluid transport through the crust takes place in domains with high permeability. For this reason, fault damage zones are a main feature where fluids may circulate unimpeded, since they have much larger permeability than normal country rocks. With the location of earthquakes, it is possible to infer fault geometry and stress field of the crust, therefore we can determine potential places where fluid circualtion is taking place. With that purpose, we installed a seismic network in an active volcanic-geothermal system, the Liquiñe-Ofqui Fault System (LOFS), located in Puyuhuapi, Southern Andes (44°-45°S). This allowed to link epicentral seismicity, focal mechanisms and surface expression of fluid circulation (hot-springs and volcanos). The LOFS is composed by two NS-striking dextral master faults, and several secondary NE-striking dextral and normal faults. Surface manifestation of fluid circulation in Puyuhuapi area are: 1) six hot-springs, most of them spatially associated with different mapped faults; 2) seven minor eruptive centers aligned over a 10-km-along one of the master NS-striking fault, and; 3) the Melimouyu strato-volcano without any spatial relationship with mapped faults. The network consists of 6 short period seismometers (S31f-2.0a sensor of IESE, with natural frequency of 2Hz), that were installed between July 2016 and August 2017; also 4 permanent broad-band seismometers (Guralp 6TD/ CD 24 sensor) which belong to the Volcano Observatory of Southern Andes (OVDAS). Preliminary results show a correlation between seismicity and surface manifestation of fluid circulation. Seismicity has a heterogeneous distribution: most of the earthquake are concentrated is the master NS-striking fault with fluid circulation manifestations; however along the segments without surface manifestation of fluids do not have seismicity. These results suggest that fluid circulation mostly occur in areas with high seismicity, and thus, the increment in fluid pressure enhances

  5. Linking space observations to volcano observatories in Latin America: Results from the CEOS DRM Volcano Pilot

    Science.gov (United States)

    Delgado, F.; Pritchard, M. E.; Biggs, J.; Arnold, D. W. D.; Poland, M. P.; Ebmeier, S. K.; Wauthier, C.; Wnuk, K.; Parker, A. L.; Amelug, F.; Sansosti, E.; Mothes, P. A.; Macedo, O.; Lara, L.; Zoffoli, S.; Aguilar, V.

    2015-12-01

    Within Latin American, about 315 volcanoes that have been active in the Holocene, but according to the United Nations Global Assessment of Risk 2015 report (GAR15) 202 of these volcanoes have no seismic, deformation or gas monitoring. Following the 2012 Santorini Report on satellite Earth Observation and Geohazards, the Committee on Earth Observation Satellites (CEOS) has developed a 3-year pilot project to demonstrate how satellite observations can be used to monitor large numbers of volcanoes cost-effectively, particularly in areas with scarce instrumentation and/or difficult access. The pilot aims to improve disaster risk management (DRM) by working directly with the volcano observatories that are governmentally responsible for volcano monitoring, and the project is possible thanks to data provided at no cost by international space agencies (ESA, CSA, ASI, DLR, JAXA, NASA, CNES). Here we highlight several examples of how satellite observations have been used by volcano observatories during the last 18 months to monitor volcanoes and respond to crises -- for example the 2013-2014 unrest episode at Cerro Negro/Chiles (Ecuador-Colombia border); the 2015 eruptions of Villarrica and Calbuco volcanoes, Chile; the 2013-present unrest and eruptions at Sabancaya and Ubinas volcanoes, Peru; the 2015 unrest at Guallatiri volcano, Chile; and the 2012-present rapid uplift at Cordon Caulle, Chile. Our primary tool is measurements of ground deformation made by Interferometric Synthetic Aperture Radar (InSAR) but thermal and outgassing data have been used in a few cases. InSAR data have helped to determine the alert level at these volcanoes, served as an independent check on ground sensors, guided the deployment of ground instruments, and aided situational awareness. We will describe several lessons learned about the type of data products and information that are most needed by the volcano observatories in different countries.

  6. The 2008 eruption of the Chaitén Volcano, Chile: a preliminary report La erupción 2008 del volcán Chaitén, Chile: informe preliminar

    Directory of Open Access Journals (Sweden)

    Luis E Lara

    2009-01-01

    Full Text Available On May 2, 2008 a Plinian eruption began on Chaiten volcano. Dome growing stage would have started on May 10-12 and extensive lahars and floods affected Chaiten town (ca. 5,000 inhabitants on May 12. A volume up to ca. 4 km³ (non DRE of rhyolitic magma would be extruded mostly during the explosive phase. Eruptive activity has not completely finished by the end of November. Because of the wide impact of this type of volcanism, this eruption poses a series of questions regarding explosive volcanism that should be addressed in the near future.El 2 de mayo se inició una erupción pliniana en el volcán Chaitén. Entre el 10 y el 12 de mayo, se habría iniciado la construcción de un domo y el día 12 de mayo lahares e inundaciones afectaron la ciudad de Chaitén (ca. 5.000 habitantes. Aproximadamente hasta 4 km³ de magma riolítico (no ERD habría sido evacuado principalmente durante la fase explosiva. Hacia fines de noviembre, la actividad eruptiva no había terminado por completo. Esta erupción plantea una serie de interrogantes científicas que deberían ser enfrentadas en un futuro cercano dado el amplio impacto que este tipo de volcanismo representa.

  7. 226Ra-230Th Disequilibria in Magmas from Llaima and Lonquimay Volcanoes, Chile: On the Roles and Rates of Subvolcanic Magmatic Processes.

    Science.gov (United States)

    Reubi, O.; Cooper, L. B.; Dungan, M. A.; Bourdon, B.

    2014-12-01

    226Ra excesses in mafic arc magmas are generally attributed to recent (contamination had a secondary influence on 226Ra-230Th disequilibria. Magmas with the highest AFC contribution have 226Ra-230Th close to equilibrium, implying that (226Ra-230Th) are mostly affected by either differentiation on time scales of ~8 kyr, or more likely, mixing with mush bodies several kyr old. Lonquimay magmas (52 to 64 wt% SiO2) are almost aphyric. Their evolution was controlled by fractional crystallization with limited crustal contamination. (226Ra-230Th) range from moderate 226Ra excesses to small deficits, and are negatively correlated with Ba/Th and MgO. These observations are difficult to reconcile with only slab-fluid addition and mantle melting. We posit that this (226Ra-230Th) range results from diffusive Ra-exchange between young recharge melts and an old crystal mush. A similar process may also explain 226Ra deficits at some other SVZ volcanoes. Thus (226Ra-230Th) in erupted magmas reflect modification of mantle-derived signatures by open-system magmatic processes in the crust. 1Sigmarsson et al., 2002, Earth and Planet. Sc. Lett. 196, 189-196. 2 Reubi et al., 2011, Earth and Planet. Sc. Lett. 303, 37-47.

  8. Geochemical characterisation of Taal volcano-hydrothermal system and temporal evolution during continued phases of unrest (1991-2017)

    Science.gov (United States)

    Maussen, Katharine; Villacorte, Edgardo; Rebadulla, Ryan R.; Maximo, Raymond Patrick; Debaille, Vinciane; Bornas, Ma. Antonia; Bernard, Alain

    2018-02-01

    Taal volcano (Luzon Island, Philippines) has last erupted in 1977 but has known some periods of increased activity, characterised by seismic swarms, ground deformation, increased carbon dioxide flux and in some cases temperature anomalies and the opening of fissures. We studied major, trace element and sulphur and strontium isotopic composition of Taal lake waters and hot springs over a period of 25 years to investigate the geochemical evolution of Taal volcano's hydrothermal system and its response to volcanic unrest. Long-term evolution of Main Crater Lake (MCL) composition shows a slow but consistent decrease of acidity, SO4, Mg, Fe and Al concentrations and a trend from light to heavy sulphate, consistent with a general decrease of volcanic gases dissolving in the hydrothermal system. Na, K and Cl concentrations remain constant indicating a non-volcanic origin for these elements. Sulphate and strontium isotopic data suggest this neutral chloride-rich component represents input of geothermal water into Taal hydrothermal system. A significant deviation from the long-term baseline can be seen in two samples from 1995. That year, pH dropped from 2.6 to 2.2, F, Si and Fe concentrations increased and Na, K and Cl concentrations decreased. Sulphate was depleted in 34S and temperature was 4 °C above baseline level at the time of sampling. We attribute these changes to the shallow intrusion of a degassing magma body during the unrest in 1991-1994. More recent unrest periods have not caused significant changes in the geochemistry of Taal hydrothermal waters and are therefore unlikely to have been triggered by shallow magma intrusion. A more likely cause for these events is thus pressurisation of the hydrothermal reservoir by increasing degassing from a stagnant magma reservoir. Our study indicates that new magmatic intrusions that might lead to the next eruption of Taal volcano are expected to change the geochemistry of MCL in the same way as in 1994-1995, with the most

  9. Insights into shallow magmatic processes at Kīlauea Volcano, Hawaiʻi, from a multiyear continuous gravity time series

    Science.gov (United States)

    Poland, Michael P.; Carbone, Daniele

    2016-01-01

    Continuous gravity data collected near the summit eruptive vent at Kīlauea Volcano, Hawaiʻi, during 2011–2015 show a strong correlation with summit-area surface deformation and the level of the lava lake within the vent over periods of days to weeks, suggesting that changes in gravity reflect variations in volcanic activity. Joint analysis of gravity and lava level time series data indicates that over the entire time period studied, the average density of the lava within the upper tens to hundreds of meters of the summit eruptive vent remained low—approximately 1000–1500 kg/m3. The ratio of gravity change (adjusted for Earth tides and instrumental drift) to lava level change measured over 15 day windows rose gradually over the course of 2011–2015, probably reflecting either (1) a small increase in the density of lava within the eruptive vent or (2) an increase in the volume of lava within the vent due to gradual vent enlargement. Superimposed on the overall time series were transient spikes of mass change associated with inflation and deflation of Kīlauea's summit and coincident changes in lava level. The unexpectedly strong mass variations during these episodes suggest magma flux to and from the shallow magmatic system without commensurate deformation, perhaps indicating magma accumulation within, and withdrawal from, void space—a process that might not otherwise be apparent from lava level and deformation data alone. Continuous gravity data thus provide unique insights into magmatic processes, arguing for continued application of the method at other frequently active volcanoes.

  10. Multifractal investigation of continuous seismic signal recorded at El Hierro volcano (Canary Islands) during the 2011-2012 pre- and eruptive phases

    Science.gov (United States)

    Telesca, Luciano; Lovallo, Michele; Martì Molist, Joan; López Moreno, Carmen; Abella Meléndez, Rafael

    2015-02-01

    The Multifractal Detrended Fluctuation Analysis (MF-DFA) is an effective method that allows detecting multifractality in non-stationary signals. We applied the MF-DFA to the continuous seismic signal recorded at El Hierro volcano (Canary Islands), which was affected by a submarine monogenetic eruption in October 2011. We investigated the multifractal properties of the continuous seismic signal before the onset of the eruption and after. We analysed three frames of the signal, one measured before the onset of eruption that occurred on October 10, 2011; and two after, but corresponding to two distinct eruptive episodes, the second one started on November 22, 2011 and lasting until late February 2012. The results obtained show a striking difference in the width of the multifractal spectrum, which is generally used to quantify the multifractal degree of a signal: the multifractal spectra of the signal frames recorded during the eruptive episodes are almost identical and much narrower than that of the signal frame measured before the onset of the eruption. Such difference indicates that the seismic signal recorded during the unrest reflects mostly the fracturing of the host rock under the overpressure exerted by the intruding magma, while that corresponding to the eruptive phases was mostly influenced by the flow of magma through the plumbing system, even some fracturing remains, not being possible to distinguish among the two eruptive episodes in terms of rock fracture mechanics.

  11. What Are Volcano Hazards?

    Science.gov (United States)

    ... Sheet 002-97 Revised March 2008 What Are Volcano Hazards? Volcanoes give rise to numerous geologic and ... as far as 15 miles from the volcano. Volcano Landslides A landslide or debris avalanche is a ...

  12. Darwin's triggering mechanism of volcano eruptions

    Science.gov (United States)

    Galiev, Shamil

    2010-05-01

    Charles Darwin wrote that ‘… the elevation of many hundred square miles of territory near Concepcion is part of the same phenomenon, with that splashing up, if I may so call it, of volcanic matter through the orifices in the Cordillera at the moment of the shock;…' and ‘…a power, I may remark, which acts in paroxysmal upheavals like that of Concepcion, and in great volcanic eruptions,…'. Darwin reports that ‘…several of the great chimneys in the Cordillera of central Chile commenced a fresh period of activity ….' In particular, Darwin reported on four-simultaneous large eruptions from the following volcanoes: Robinson Crusoe, Minchinmavida, Cerro Yanteles and Peteroa (we cite the Darwin's sentences following his The Voyage of the Beagle and researchspace. auckland. ac. nz/handle/2292/4474). Let us consider these eruptions taking into account the volcano shape and the conduit. Three of the volcanoes (Minchinmavida (2404 m), Cerro Yanteles (2050 m), and Peteroa (3603 m)) are stratovolcanos and are formed of symmetrical cones with steep sides. Robinson Crusoe (922 m) is a shield volcano and is formed of a cone with gently sloping sides. They are not very active. We may surmise, that their vents had a sealing plug (vent fill) in 1835. All these volcanoes are conical. These common features are important for Darwin's triggering model, which is discussed below. The vent fill material, usually, has high level of porosity and a very low tensile strength and can easily be fragmented by tension waves. The action of a severe earthquake on the volcano base may be compared with a nuclear blast explosion of the base. It is known, that after a underground nuclear explosion the vertical motion and the surface fractures in a tope of mountains were observed. The same is related to the propagation of waves in conical elements. After the explosive load of the base. the tip may break and fly off at high velocity. Analogous phenomenon may be generated as a result of a

  13. Hawaii's volcanoes revealed

    Science.gov (United States)

    Eakins, Barry W.; Robinson, Joel E.; Kanamatsu, Toshiya; Naka, Jiro; Smith, John R.; Takahashi, Eiichi; Clague, David A.

    2003-01-01

    Hawaiian volcanoes typically evolve in four stages as volcanism waxes and wanes: (1) early alkalic, when volcanism originates on the deep sea floor; (2) shield, when roughly 95 percent of a volcano's volume is emplaced; (3) post-shield alkalic, when small-volume eruptions build scattered cones that thinly cap the shield-stage lavas; and (4) rejuvenated, when lavas of distinct chemistry erupt following a lengthy period of erosion and volcanic quiescence. During the early alkalic and shield stages, two or more elongate rift zones may develop as flanks of the volcano separate. Mantle-derived magma rises through a vertical conduit and is temporarily stored in a shallow summit reservoir from which magma may erupt within the summit region or be injected laterally into the rift zones. The ongoing activity at Kilauea's Pu?u ?O?o cone that began in January 1983 is one such rift-zone eruption. The rift zones commonly extend deep underwater, producing submarine eruptions of bulbous pillow lava. Once a volcano has grown above sea level, subaerial eruptions produce lava flows of jagged, clinkery ?a?a or smooth, ropy pahoehoe. If the flows reach the ocean they are rapidly quenched by seawater and shatter, producing a steep blanket of unstable volcanic sediment that mantles the upper submarine slopes. Above sea level then, the volcanoes develop the classic shield profile of gentle lava-flow slopes, whereas below sea level slopes are substantially steeper. While the volcanoes grow rapidly during the shield stage, they may also collapse catastrophically, generating giant landslides and tsunami, or fail more gradually, forming slumps. Deformation and seismicity along Kilauea's south flank indicate that slumping is occurring there today. Loading of the underlying Pacific Plate by the growing volcanic edifices causes subsidence, forming deep basins at the base of the volcanoes. Once volcanism wanes and lava flows no longer reach the ocean, the volcano continues to submerge, while

  14. Continuous terrestrial geodetic monitoring of the 2007 Lava Fan in the Sciara de Fuoco (Stromboli volcano, Italy)

    Science.gov (United States)

    Puglisi, G.; Bonforte, A.; Cantarero, M.; Spata, A.

    2009-12-01

    At the end of the 2002-2003 eruption, a terrestrial monitoring system was set up to regularly measure the movements of benchmarks installed inside the Sciara del Fuoco (hereafter SdF) (Puglisi et al., 2005). This system, named THEODOROS, is based on a remotely controlled robotized Total Station installed near Punta Labronzo, on the northern border of the SdF. The 2007 eruption caused a dramatic change in the operations of THEODOROS. Indeed, the 2007 lava flows destroyed all the benchmarks installed on the northern part of the SdF, leaving only those on its central part. This eruption produced a lava fan at the base of the SdF, due to the rapid cooling of the lava flows on entering the sea. The continuous overlapping of several flows during the eruption built a thick lava body (the fan); it was emplaced on a very steep slope, partially originated during the landslides occurring in December 2002, producing a hazardous condition due to the potential sudden sliding of this fan into the sea. In order to monitor the stability of this lava fan, a new terrestrial geodetic network, was implemented on 6 April 2007, by installing 5 reflectors along a profile crossing the lava body, approximately over the old coastline. Later, in June 2007, 4 more reflectors were installed at higher and lower altitudes with respect to the previous profile, to obtain more information on the overall deformation of the lava body. Measurements were rather noisy during the first months, but a better definition of the reference system strongly improved the quality of the data. The position of the 9 benchmarks over the lava fan enable the areal distribution of the deformation to be drawn. The measurements carried out every 10 minutes allow following their motion with high temporal detail. The data collected since the end of the eruption highlighted a significant downslope motion of the entire lava fan, decreasing from the South to the North, where the body is buttressed by the rocky northern wall of

  15. Radon emanometry in active volcanoes

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, J.L.; Monnin, M. (CNRS, IN2P3, BP45/F63170 Aubiere (France)); Cejudo, J. (Instituto Nacional de Investigaciones Nucleares, Mexico City)

    1984-01-01

    Radon emission measurements from active volcanoes has, since 1981, been continuously measured at monitoring stations in Mexico and in Costa Rica. Counting of etched alpha tracks on cellulose nitrate LR-115 detectors give varying results at the several stations. Radon emanation at Chichon, where an explosive eruption occurred in 1982, fell down. Radon detection at the active volcano in Colima shows a pattern of very low emission. At the Costa Rica stations located at Poas, Arenal and Irazu, the radon emanation shows regularity.

  16. Geology of kilauea volcano

    Science.gov (United States)

    Moore, R.B.; Trusdell, F.A.

    1993-01-01

    This paper summarizes studies of the structure, stratigraphy, petrology, drill holes, eruption frequency, and volcanic and seismic hazards of Kilauea volcano. All the volcano is discussed, but the focus is on its lower cast rift zone (LERZ) because active exploration for geothermal energy is concentrated in that area. Kilauea probably has several separate hydrothermal-convection systems that develop in response to the dynamic behavior of the volcano and the influx of abundant meteoric water. Important features of some of these hydrothermal-convection systems are known through studies of surface geology and drill holes. Observations of eruptions during the past two centuries, detailed geologic mapping, radiocarbon dating, and paleomagnetic secular-variation studies indicate that Kilauea has erupted frequently from its summit and two radial rift zones during Quaternary time. Petrologic studies have established that Kilauea erupts only tholeiitic basalt. Extensive ash deposits at Kilauea's summit and on its LERZ record locally violent, but temporary, disruptions of local hydrothermal-convection systems during the interaction of water or steam with magma. Recent drill holes on the LERZ provide data on the temperatures of the hydrothermal-convection systems, intensity of dike intrusion, porosity and permeability, and an increasing amount of hydrothermal alteration with depth. The prehistoric and historic record of volcanic and seismic activity indicates that magma will continue to be supplied to deep and shallow reservoirs beneath Kilauea's summit and rift zones and that the volcano will be affected by eruptions and earthquakes for many thousands of years. ?? 1993.

  17. From Chaitén to the Chilean volcano monitoring network Jorge Munoz, Hugo Moreno, Servicio Nacional de Geología y Minería, Chile, jmunoz@sernageomin.cl

    Science.gov (United States)

    Muñoz, J.; Moreno, H.

    2010-12-01

    Chaitén volcano in southern Andes started a plinian to subplinian rhyolitic eruption on May 2008 following a long period of quiescence. A new dome complex grew up at high rates during 2008-2009 inside a 2 kilometers caldera like structure. Pyroclastic, laharic, block and ash flows and ash falls deposits have been affecting the surrounding populations, ground, vegetation, ocean and rivers, such as the laharic flows burying the currently evacuated Chaitén city. The geological, volcanologic and seismic knowledge produced during the eruption and the determination of evolutionary sceneries were properly transferred and consequently taken in account during complex decisions of authorities in charge of the emergency. As a result, no fatalities or major people injuries were produced during this rhyolitic eruption. Mainly as the consequence of the eruption of the Chaitén volcano but also due to the valuable technical advice during the crisis management, evacuation, hazards evolution, volcanic alerts and selection of sites for relocation of the Chaitén city provided by geologist and volcanologist from SERNAGEOMIN, the funding for the National Volcano Monitoring Network (RNVV) was approved during 2008 and it was integrated as a Bicentenary initiative. During the lapse of 5 year, RNVV need to create professional capacity and working teams, improve the current volcano observatory at Temuco and conform three new observatories at Coihaique, Talca and Antofagasta cities to implement volcano monitoring networks at the 43 hazardous volcanoes along the Chilean Andes. Monitoring net is currently conformed by seismic stations in 10 volcanoes or volcanic groups (San Pedro-San Pablo in Central Volcanic Andes and Llaima, Villlarrica, Mocho-Choshuenco, Carrán-Los Venados, Cordón Caulle, Osorno, Calbuco, Chaitén and Melimoyu in the southern volcanic Andes), in addition to gas measure and video camera stations in Llaima, Villarrica and Chaitén volcanoes. In addition, the geologic and

  18. A multidisciplinary and multi-sensor assessment of continuous degassing at Turrialba volcano, Costa Rica; insights and their application to hazard management

    Science.gov (United States)

    van Manen, S. M.; Tortini, R.; Burson, B.; Carn, S. A.

    2013-12-01

    Turrialba is an active stratovolcano located in the Central Cordillera of Costa Rica with an elevation of 3,340 m. Located just 35 km northeast of Costa Rica's capital city San Jose it looms over Costa Rica's Central Valley, the social and economic hub of the country. After more than 100 years of quiescence Turrialba resumed activity in 1996, marked by progressive increases in degassing and seismic activity with gas emissions becoming continuous in 2007. Intermittent phreatic explosions accompanied by ash emissions that have reached the capital have been occurring since 2010. The activity has resulted in the evacuation of two villages, closure of the National Park that comprises the summit region of the volcano and devastation of the local ecosystem. In this work we present a multi-disciplinary and multi-sensor assessment of the persistent degassing and its impacts on the local ecosystem. Combining a variety of high temporal and high spatial resolution satellite-based time series with ground-based measurements of ambient gas concentrations, element deposition and surveys of species richness, enables a comprehensive assessment of SO2 emissions and changes in vegetation. Satellite-based time-series were obtained from Landsat TM and ETM+, Terra ASTER and MODIS, Aqua MODIS, EO-1 and Aura OMI, with some of the data dating back to 2000. Preliminary results show exposure to the volcanic plume results in high soil acidity and significant uptake of certain heavy metals (e.g. Cd, Co, Cu, Hg and Pb) by vegetation, in contrast other elements such as Ba, Ca and Sr are leached from the soil as a result of the acid deposition. These factors are likely to be responsible for decreased species richness and physiological damage observed downwind of Turrialba. Ambient SO2 concentrations that exceed WHO guideline values have been recorded, which has potentially important consequences for human health in the area. Analyzing and relating the remote observations to conditions and impacts

  19. Satellite and ground-based analysis of the effects on vegetation of continuous SO2 degassing at Turrialba volcano (Costa Rica) and its application to hazard management

    Science.gov (United States)

    Tortini, R.; van Manen, S. M.; Burson, B.; Carn, S. A.

    2014-12-01

    Turrialba is an active stratovolcano located 35 km northeast of San Jose, Costa Rica's capital city and socioeconomic hub. After over 100 years of quiescence Turrialba resumed activity in 1996 progressively increasing its degassing and seismic activity, showing continuous gas emissions since 2007. Intermittent phreatic explosions with ash emissions that have reached the capital have occurred since 2010. This activity has resulted in the temporary evacuation of two villages, closure of the National Park that comprises the summit region of the volcano and devastation of the local ecosystem. We combined a variety of satellite-based time series with ground-based measurements of ambient gas concentrations, element deposition and surveys of species richness to enable a comprehensive assessment of SO2 emissions and changes in vegetation. Satellite-based time-series were obtained from Landsat ETM+, Terra ASTER, Terra/Aqua MODIS and Aura OMI, with some of the data dating back to 2000. From 2007-2010 we observed emissions of SO2 and loss of vegetation healthiness (i.e. decrease of EVI2) downwind of the vents. From 2010 onwards these stabilized, but we observe an apparent decrease in agriculture. Other multi-temporal products, such as the ALOS PALSAR FNF data, confirm our observations. The exposure to the volcanic plume resulted in high soil acidity and significant uptake of certain heavy metals by vegetation; in contrast other elements are leached from the soil as a result of the acid deposition. These factors are likely to be responsible for decreased species richness and physiological damage observed at Turrialba. Our study shows ecological impacts, in terms of soil characteristics, vegetation composition and diversity and physiological damage of vegetation, which all correlate to fumigation by Turrialba's plume. Analyzing and relating the remote observations to conditions and impacts on the ground provides a better understanding of volcanic degassing, its impacts on

  20. Central Chile

    Science.gov (United States)

    2002-01-01

    The beginning of spring in central Chile looked like this to SeaWiFS. The snow-covered Andes mark the country's eastern border, and phytoplankton blooms and river sediment plumes fill the waters off its west coast. A large eddy due west of Concepcion is highlighted by the phytoplankton it contains.

  1. Geology of Kilauea volcano

    Energy Technology Data Exchange (ETDEWEB)

    Moore, R.B. (Geological Survey, Denver, CO (United States). Federal Center); Trusdell, F.A. (Geological Survey, Hawaii National Park, HI (United States). Hawaiian Volcano Observatory)

    1993-08-01

    This paper summarizes studies of the structure, stratigraphy, petrology, drill holes, eruption frequency, and volcanic and seismic hazards of Kilauea volcano. All the volcano is discussed, but the focus is on its lower east rift zone (LERZ) because active exploration for geothermal energy is concentrated in that area. Kilauea probably has several separate hydrothermal-convection systems that develop in response to the dynamic behavior of the volcano and the influx of abundant meteoric water. Important features of some of these hydrothermal-convection systems are known through studies of surface geology and drill holes. Observations of eruptions during the past two centuries, detailed geologic mapping, radiocarbon dating, and paleomagnetic secular-variation studies indicate that Kilauea has erupted frequently from its summit and two radial rift zones during Quaternary time. Petrologic studies have established that Kilauea erupts only tholeiitic basalt. Extensive ash deposits at Kilauea's summit and on its LERZ record locally violent, but temporary, disruptions of local hydrothermal-convection systems during the interaction of water or steam with magma. Recent drill holes on the LERZ provide data on the temperatures of the hydrothermal-convection systems, intensity of dike intrusion, porosity and permeability, and an increasing amount of hydrothermal alteration with depth. The prehistoric and historic record of volcanic and seismic activity indicates that magma will continue to be supplied to deep and shallow reservoirs beneath Kilauea's summit and rift zones and that the volcano will be affected by eruptions and earthquakes for many thousands of years. 71 refs., 2 figs.

  2. Strontium isotope data for recent andesites in Ecuador and North Chile

    International Nuclear Information System (INIS)

    Francis, P.W.; Thorpe, R.S.; Moorbath, S.

    1977-01-01

    New Sr isotope data are presented for andesite lavas from active volcanoes in Ecuador and North Chile. Twenty-three samples from five Ecuadorian volcanoes have 87 Sr/ 86 Sr ratios most of which are essentially within analytical error, and average 0.7044. In contrast, 16 samples from the San Pedro-San Pablo volcano complex in North Chile have 87 Sr/ 86 Sr ratios between 0.7058 and 0.7072. These samples show no correlation between 87 Sr/ 86 Sr and 87 Rb/ 86 Sr, nor between 87 Sr/ 86 Sr and other elements or ratios. The major difference in setting between the two volcanic provinces lies in the thickness of the continental crust; 40-50 km beneath Ecuador, 70 km beneath North Chile. Andesites from both areas are derived primarily from the mantle, but those from North Chile show evidence of a significant Sr isotopic contribution from the continental crust. (Auth.)

  3. Chile; Staff Report for the 2003 Article IV Consultation

    OpenAIRE

    International Monetary Fund

    2003-01-01

    Chile has successfully resisted contagion from neighboring countries difficulties. Chile's inflation targeting framework has successfully anchored inflation expectations and increased the economy's resilience to external shocks while maintaining price stability. The floating exchange rate regime is an essential part of the macroeconomic policy framework and continues to serve Chile well. The interest in recapitalizing the central bank is welcomed. Executive Directors commend Chile for the tra...

  4. Tourism in Chile | CTIO

    Science.gov (United States)

    Program PIA Program GO-FAAR Program Other Opportunities Tourism Visits to Tololo Astro tourism in Chile Tourism in Chile Information for travelers Visit Tololo Media Relations News Press Release Publications ‹› You are here CTIO Home » Outreach » Tourism » Tourism in Chile Tourism in Chile Map of

  5. Global Volcano Locations Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC maintains a database of over 1,500 volcano locations obtained from the Smithsonian Institution Global Volcanism Program, Volcanoes of the World publication. The...

  6. A Scientific Excursion: Volcanoes.

    Science.gov (United States)

    Olds, Henry, Jr.

    1983-01-01

    Reviews an educationally valuable and reasonably well-designed simulation of volcanic activity in an imaginary land. VOLCANOES creates an excellent context for learning information about volcanoes and for developing skills and practicing methods needed to study behavior of volcanoes. (Author/JN)

  7. Volcano seismology

    Science.gov (United States)

    Chouet, B.

    2003-01-01

    A fundamental goal of volcano seismology is to understand active magmatic systems, to characterize the configuration of such systems, and to determine the extent and evolution of source regions of magmatic energy. Such understanding is critical to our assessment of eruptive behavior and its hazardous impacts. With the emergence of portable broadband seismic instrumentation, availability of digital networks with wide dynamic range, and development of new powerful analysis techniques, rapid progress is being made toward a synthesis of high-quality seismic data to develop a coherent model of eruption mechanics. Examples of recent advances are: (1) high-resolution tomography to image subsurface volcanic structures at scales of a few hundred meters; (2) use of small-aperture seismic antennas to map the spatio-temporal properties of long-period (LP) seismicity; (3) moment tensor inversions of very-long-period (VLP) data to derive the source geometry and mass-transport budget of magmatic fluids; (4) spectral analyses of LP events to determine the acoustic properties of magmatic and associated hydrothermal fluids; and (5) experimental modeling of the source dynamics of volcanic tremor. These promising advances provide new insights into the mechanical properties of volcanic fluids and subvolcanic mass-transport dynamics. As new seismic methods refine our understanding of seismic sources, and geochemical methods better constrain mass balance and magma behavior, we face new challenges in elucidating the physico-chemical processes that cause volcanic unrest and its seismic and gas-discharge manifestations. Much work remains to be done toward a synthesis of seismological, geochemical, and petrological observations into an integrated model of volcanic behavior. Future important goals must include: (1) interpreting the key types of magma movement, degassing and boiling events that produce characteristic seismic phenomena; (2) characterizing multiphase fluids in subvolcanic

  8. Continuous gravity and tilt reveal anomalous pressure and density changes associated with gas pistoning within the summit lava lake of Kīlauea Volcano, Hawaiʻi

    Science.gov (United States)

    Poland, Michael; Carbone, Daniele

    2018-01-01

    Gas piston events within the summit eruptive vent of Kīlauea Volcano, Hawai‘i, are characterized by increases in lava level and by decreases in seismic energy release, spattering, and degassing. During 2010–2011, gas piston events were especially well manifested, with lava level rises of tens of meters over the course of several hours, followed by a sudden drop to preevent levels. The changes in lava level were accompanied by directly proportional changes in gravity, but ground deformation determined from tilt was anticorrelative. The small magnitude of the gravity changes, compared to the large changes in volume within the vent during gas pistons, suggests that pistoning involves the accumulation of a very low‐density (100–200 kg/m3) foam at the top of the lava column. Co‐event ground tilt indicates that rise in lava level is paradoxically associated with deflation (the opposite is usually true), which can be modeled as an increase in the gas content of the magma column between the source reservoir and the surface. Gas pistoning behavior is therefore associated with not only accumulation of a shallow magmatic foam but also more bubbles within the feeder conduit, probably due to the overall decrease in gas emissions from the lava lake during piston events.

  9. Seismic-induced accelerations detected by two parallel gravity meters in continuous recording with a high sampling rate at Etna volcano

    Directory of Open Access Journals (Sweden)

    P. Stefanelli

    2008-06-01

    Full Text Available We analyse a microgravity data set acquired from two spring LaCoste & Romberg gravity meters operated in parallel at the same site on Etna volcano (Italy for about two months (August – September 2005. The high sampling rate acquisition (2Hz allowed the correlation of short-lasting gravity fluctuations with seismic events. After characterizing the oscillation behavior of the meters, through the study of spectral content and the background noise level of both sequences, we recognized fluctuations in the gravity data, spanning a range of periods from 1 second to about 30 seconds dominated by components with a period of about 15 ÷ 25 seconds, during time intervals encompassing both local seismic events and large worldwide earthquakes. The data analyses demonstrate that observed earthquake-induced gravity fluctuations have some differences due to diverse spectral content of the earthquakes. When local seismic events which present high frequency content excite the meters, the correlation between the two gravity signals is poor (factor < 0.3. Vice versa, when large worldwide earthquakes occur and low frequency seismic waves dominate the ensuing seismic wavefield, the resonance frequencies of the meters are excited and they react according to more common features. In the latter case, the signals from the two instruments are strongly correlated to each other (up to 0.9. In this paper the behaviors of spring gravimeters in the frequency range of the disturbances produced by local and large worldwide earthquakes are presented and discussed.

  10. Geology, petrology and geochemistry of the dome complex of Huequi volcano, southern Chile Geología, petrología y geoquímica de los domos volcánicos del volcán Huequi, Chile meridional

    Directory of Open Access Journals (Sweden)

    Sebastian F.L Watt

    2011-07-01

    Full Text Available Huequi, a little-known volcano in the southern part of the Andean southern volcanic zone (SSVZ, shows a regionally unusual eruption style, mineralogy and geochemistry. The volcano comprises multiple highly-eroded lava domes. Past eruptions were accompanied by relatively minor explosive activity, most recently from 1890-1920. The rocks erupted by Huequi range from basaltic andesite to dacite, and are highly distinctive when compared to other volcanoes of the SSVZ, being K-poor and Al-rich, and containing euhedral hornblende phenocrysts. Overall compositions suggest a notably water-rich magma source, evolving through high levels of fractionation and subsequent degassing to produce highly porphyritic dome-forming andesites. The ultimate causes of water-rich magmas at this point in the arc remain unclear.El volcán Huequi es poco conocido, que se ubica en la provincia sur de la zona Volcánica Sur de los Andes (ZVSS. Sus tipos de erupción y características mineralógicas y geoquímicas son poco comunes a nivel regional. El volcán presenta múltiples domos poco erosionados. Las erupciones estuvieron acompañadas por una actividad explosiva secundaria, siendo las más recientes las ocurridas entre los años 1890 y 1920. Los magmas del Huequi son de composición andesítico-basáltica a dacítica. Si se las compara con rocas eruptadas por otros centros volcánicos de la ZVSS de los Andes, las del Huequi se caracterizan por ser pobres en K, ricas en Al y por presentar fenocristales euhedrales de anfíbola. Las composiciones totales sugieren una fuente magmática rica en H2O, que se desarrolla a través de niveles de cristalización fraccionada y desgasificación subsecuente, que producen domos volcánicos andesíticos altamente porfíricos. Sin embargo, la causa última que genera magmas ricos en H2O, en esta parte de los Andes, sigue aún sin explicación.

  11. Characteristics of Hawaiian volcanoes

    Science.gov (United States)

    Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.

    2014-01-01

    Founded in 1912 at the edge of the caldera of Kīlauea Volcano, HVO was the vision of Thomas A. Jaggar, Jr., a geologist from the Massachusetts Institute of Technology, whose studies of natural disasters around the world had convinced him that systematic, continuous observations of seismic and volcanic activity were needed to better understand—and potentially predict—earthquakes and volcanic eruptions. Jaggar summarized the aim of HVO by stating that “the work should be humanitarian” and have the goals of developing “prediction and methods of protecting life and property on the basis of sound scientific achievement.” These goals align well with those of the USGS, whose mission is to serve the Nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage natural resources; and enhance and protect our quality of life.

  12. Soufriere Hills Volcano

    Science.gov (United States)

    2002-01-01

    In this ASTER image of Soufriere Hills Volcano on Montserrat in the Caribbean, continued eruptive activity is evident by the extensive smoke and ash plume streaming towards the west-southwest. Significant eruptive activity began in 1995, forcing the authorities to evacuate more than 7,000 of the island's original population of 11,000. The primary risk now is to the northern part of the island and to the airport. Small rockfalls and pyroclastic flows (ash, rock and hot gases) are common at this time due to continued growth of the dome at the volcano's summit.This image was acquired on October 29, 2002 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. Science team leader; Bjorn Eng of JPL is the project manager. The Terra mission is part of NASA

  13. Volcanoes: Nature's Caldrons Challenge Geochemists.

    Science.gov (United States)

    Zurer, Pamela S.

    1984-01-01

    Reviews various topics and research studies on the geology of volcanoes. Areas examined include volcanoes and weather, plate margins, origins of magma, magma evolution, United States Geological Survey (USGS) volcano hazards program, USGS volcano observatories, volcanic gases, potassium-argon dating activities, and volcano monitoring strategies.…

  14. Chile Energy Policy Review 2009

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-10-22

    Since 1990, Chile has been the fastest growing economy in Latin America thanks to sound economic management and integration into the global economy. Chile can also be proud of its energy policy achievements. The pioneering privatisation and liberalisation of its electricity sector in the 1980s was the foundation for a competitive energy sector, which has sustained the rapid growth of the Chilean economy over the past two decades. Nonetheless, Chile faces the continuing challenge of finding additional energy supplies to fuel economic growth. Chile has limited fossil energy resources and depends on imports to meet three-quarters of its energy needs. The country's electricity sector has faced three periods of significant stress over the past decade. The last episode took place in 2007/2008, when the loss of natural gas imports from Argentina was further exacerbated by a drought in the central system, where hydropower normally accounts for over half of electricity generation. Drawing on the experience of IEA member countries, the Review assesses Chile's major energy challenges and provides recommendations. Six main themes emerge: the successful liberalisation of the power sector in the 1980s; the essential role played by the state in ensuring energy security; the re-formulation of Chile's long-term energy policy; the proposed reorganisation of the institutional framework; greater independence for the system operators; and the need for a clear framework of regulation so that long-term investment decisions integrate social and environmental costs. This publication is essential reading for all who are interested in Chilean energy issues and in learning about the important role sound energy policy can play in developing a nation's economic and social welfare.

  15. Volcanoes: observations and impact

    Science.gov (United States)

    Thurber, Clifford; Prejean, Stephanie G.

    2012-01-01

    Volcanoes are critical geologic hazards that challenge our ability to make long-term forecasts of their eruptive behaviors. They also have direct and indirect impacts on human lives and society. As is the case with many geologic phenomena, the time scales over which volcanoes evolve greatly exceed that of a human lifetime. On the other hand, the time scale over which a volcano can move from inactivity to eruption can be rather short: months, weeks, days, and even hours. Thus, scientific study and monitoring of volcanoes is essential to mitigate risk. There are thousands of volcanoes on Earth, and it is impractical to study and implement ground-based monitoring at them all. Fortunately, there are other effective means for volcano monitoring, including increasing capabilities for satellite-based technologies.

  16. Robotics research in Chile

    Directory of Open Access Journals (Sweden)

    Javier Ruiz-del-Solar

    2016-12-01

    Full Text Available The development of research in robotics in a developing country is a challenging task. Factors such as low research funds, low trust from local companies and the government, and a small number of qualified researchers hinder the development of strong, local research groups. In this article, and as a case of study, we present our research group in robotics at the Advanced Mining Technology Center of the Universidad de Chile, and the way in which we have addressed these challenges. In 2008, we decided to focus our research efforts in mining, which is the main industry in Chile. We observed that this industry has needs in terms of safety, productivity, operational continuity, and environmental care. All these needs could be addressed with robotics and automation technology. In a first stage, we concentrate ourselves in building capabilities in field robotics, starting with the automation of a commercial vehicle. An important outcome of this project was the earn of the local mining industry confidence. Then, in a second stage started in 2012, we began working with the local mining industry in technological projects. In this article, we describe three of the technological projects that we have developed with industry support: (i an autonomous vehicle for mining environments without global positioning system coverage; (ii the inspection of the irrigation flow in heap leach piles using unmanned aerial vehicles and thermal cameras; and (iii an enhanced vision system for vehicle teleoperation in adverse climatic conditions.

  17. Volcano monitoring with an infrared camera: first insights from Villarrica Volcano

    Science.gov (United States)

    Rosas Sotomayor, Florencia; Amigo Ramos, Alvaro; Velasquez Vargas, Gabriela; Medina, Roxana; Thomas, Helen; Prata, Fred; Geoffroy, Carolina

    2015-04-01

    This contribution focuses on the first trials of the, almost 24/7 monitoring of Villarrica volcano with an infrared camera. Results must be compared with other SO2 remote sensing instruments such as DOAS and UV-camera, for the ''day'' measurements. Infrared remote sensing of volcanic emissions is a fast and safe method to obtain gas abundances in volcanic plumes, in particular when the access to the vent is difficult, during volcanic crisis and at night time. In recent years, a ground-based infrared camera (Nicair) has been developed by Nicarnica Aviation, which quantifies SO2 and ash on volcanic plumes, based on the infrared radiance at specific wavelengths through the application of filters. Three Nicair1 (first model) have been acquired by the Geological Survey of Chile in order to study degassing of active volcanoes. Several trials with the instruments have been performed in northern Chilean volcanoes, and have proven that the intervals of retrieved SO2 concentration and fluxes are as expected. Measurements were also performed at Villarrica volcano, and a location to install a ''fixed'' camera, at 8km from the crater, was discovered here. It is a coffee house with electrical power, wifi network, polite and committed owners and a full view of the volcano summit. The first measurements are being made and processed in order to have full day and week of SO2 emissions, analyze data transfer and storage, improve the remote control of the instrument and notebook in case of breakdown, web-cam/GoPro support, and the goal of the project: which is to implement a fixed station to monitor and study the Villarrica volcano with a Nicair1 integrating and comparing these results with other remote sensing instruments. This works also looks upon the strengthen of bonds with the community by developing teaching material and giving talks to communicate volcanic hazards and other geoscience topics to the people who live "just around the corner" from one of the most active volcanoes

  18. United States-Chile binational exchange for volcanic risk reduction, 2015—Activities and benefits

    Science.gov (United States)

    Pierson, Thomas C.; Mangan, Margaret T.; Lara Pulgar, Luis E.; Ramos Amigo, Álvaro

    2017-07-25

    In 2015, representatives from the United States and Chile exchanged visits to discuss and share their expertise and experiences dealing with volcano hazards. Communities in both countries are at risk from various volcano hazards. Risks to lives and property posed by these hazards are a function not only of the type and size of future eruptions but also of distances from volcanoes, structural integrity of volcanic edifices, landscape changes imposed by recent past eruptions, exposure of people and resources to harm, and any mitigative measures taken (or not taken) to reduce risk. Thus, effective risk-reduction efforts require the knowledge and consideration of many factors, and firsthand experience with past volcano crises provides a tremendous advantage for this work. However, most scientists monitoring volcanoes and most officials delegated with the responsibility for emergency response and management in volcanic areas have little or no firsthand experience with eruptions or volcano hazards. The reality is that eruptions are infrequent in most regions, and individual volcanoes may have dormant periods lasting hundreds to thousands of years. Knowledge may be lacking about how to best plan for and manage future volcanic crises, and much can be learned from the sharing of insights and experiences among counterpart specialists who have had direct, recent, or different experiences in dealing with restless volcanoes and threatened populations. The sharing of information and best practices can help all volcano scientists and officials to better prepare for future eruptions or noneruptive volcano hazards, such as large volcanic mudflows (lahars), which could affect their communities.

  19. Current Discussions Between ESO and Chile

    Science.gov (United States)

    1995-04-01

    [Joint Press Release by the Government of the Republic of Chile and the European Southern Observatory. The text is issued simultaneously in Santiago de Chile (in Spanish) and at the ESO Headquarters in Garching (in English).] Today, Tuesday, 18 April 1995, at the ESO Headquarters in Garching (Germany), Mr. Roberto Cifuentes, Plenipotentiary Ambassador representing the Government of the Republic of Chile, and the Director General of the European Southern Observatory, Professor Riccardo Giacconi, have signed a Supplementary, Interpretative and Amending Agreement to the Convention of 6 November 1963 which governs the relations between Chile and this International Organisation. This Agreement which in practice signifies a widening and strengthening of the cooperative relations between the Organisation and the Chilean scientific community will hereafter be submitted for ratification by the National Congress of the Republic of Chile (the Parliament) and by the ESO Council. According to the Agreement signed today, Chilean astronomers will have privileged access within up to 10 percent observing time on all present and future ESO telescopes in Chile. Moreover, ESO accepts to incorporate into its labour regulations for Chilean personnel concepts like freedom of association and collective bargaining. This signing of the Supplementary, Interpretative and Amending Agreement to the original Convention of 1963 follows after months of constructive dialogue between the parties. It constitutes an important step towards a solution of some of the pending points on the current agenda for discussions between the Government of Chile and ESO. Among the issues still pending, ESO has informed the Government of Chile that respect for its immunities by the Chilean State is of vital importance for the continuation of the construction of the world's largest telescope at Paranal, as well as the continued presence of the Organisation in Chile. The Chilean Government, on its side, and concerning

  20. Visions of Volcanoes

    Directory of Open Access Journals (Sweden)

    David M. Pyle

    2017-12-01

    Full Text Available The long nineteenth century marked an important transition in the understanding of the nature of combustion and fire, and of volcanoes and the interior of the earth. It was also a period when dramatic eruptions of Vesuvius lit up the night skies of Naples, providing ample opportunities for travellers, natural philosophers, and early geologists to get up close to the glowing lavas of an active volcano. This article explores written and visual representations of volcanoes and volcanic activity during the period, with the particular perspective of writers from the non-volcanic regions of northern Europe. I explore how the language of ‘fire’ was used in both first-hand and fictionalized accounts of peoples’ interactions with volcanoes and experiences of volcanic phenomena, and see how the routine or implicit linkage of ‘fire’ with ‘combustion’ as an explanation for the deep forces at play within and beneath volcanoes slowly changed as the formal scientific study of volcanoes developed. I show how Vesuvius was used as a ‘model’ volcano in science and literature and how, later, following devastating eruptions in Indonesia and the Caribbean, volcanoes took on a new dimension as contemporary agents of death and destruction.

  1. Caída de tefra y su influencia sobre la estructura y dinámica de los bosques andinos de Nothofagus en el Parque Nacional Puyehue, Chile

    Science.gov (United States)

    Mauricio Montiel; Mauro E González; Charles M Crisafulli

    2016-01-01

    Tephra fall influences the structure and dynamics of Andean Nothofagus (beech) forests in Puyehue National Park, Chile. Forest mortality and subsequent establishment, structure and composition have been affected by the eruption of the Puyehue-Cordon Caulle volcano complex.

  2. Volcano-tectonic deformation in the Kivu Region, Central Africa: Results from six years of continuous GNSS observations of the Kivu Geodetic Network (KivuGNet)

    Science.gov (United States)

    Geirsson, Halldor; d'Oreye, Nicolas; Mashagiro, Niche; Syauswa, Muhindo; Celli, Gilles; Kadufu, Benjamin; Smets, Benoît; Kervyn, François

    2017-10-01

    We present an overview of the installation, operation, and initial results of the 15-station KivuGNet (Kivu Geodetic Network) in the Kivu Region, Central Africa. The network serves primarily as a research and monitoring tool for active volcanic, earthquake, and plate boundary processes in the region. Continuous operation of in-situ measurement networks in naturally and politically harsh environments is challenging, but has proven fruitful in this case. During the operation of the network since 2009, KivuGNet has captured: co-eruptive deformation from two eruptions of Nyamulagira (in 2010 and 2011-2012); inter-eruptive deformation, which we interpret as a combination of plate motion across the Western - East Africa Rift, and decreasing deep-seated magma accumulation under the Nyiragongo-Nyamulagira region; co-seismic deformation from the Mw5.8 August 7, 2015 Lwiro earthquake at the western border of Lake Kivu. We hope that this study will serve as a motivation for further implementation of in-situ geodetic networks in under-monitored and under-studied sections of the East African Rift.

  3. 75 FR 3756 - Preserved Mushrooms from Chile, China, India, and Indonesia

    Science.gov (United States)

    2010-01-22

    ...)] Preserved Mushrooms from Chile, China, India, and Indonesia AGENCY: United States International Trade... preserved mushrooms from Chile, China, India, and Indonesia. SUMMARY: The Commission hereby gives notice of... mushrooms from Chile, China, India, and Indonesia would be likely to lead to continuation or recurrence of...

  4. Delineation of the High Enthalpy Reservoirs of the Sierra Nevada Volcanic Geothermal System, South-Central Chile

    Science.gov (United States)

    Alam, M.; Muñoz, M.; Parada, M.

    2011-12-01

    Geothermal system associated with the Pleistocene-Holocene Sierra Nevada volcano (SNVGS) in the Araucanía Region of Chile has surface manifestations from the north-western flank of the volcano, up to Manzanar and Malalcahuello. Baños del Toro, located on the northwestern flank of the volcano, has numerous fumaroles and acid pools (acid sulfate waters, T=~90°C, pH=2.1, TDS=3080 mg/L); while Aguas de la Vaca, near the base of the volcano, has a bubbling spring (chloride-sulfate waters, T=~60°C, pH=7.0, TDS=950 mg/L). Five shallow (Geotermia) of the Ministry of Energy and Mining, Government of Chile.

  5. Advances in volcano monitoring and risk reduction in Latin America

    Science.gov (United States)

    McCausland, W. A.; White, R. A.; Lockhart, A. B.; Marso, J. N.; Assitance Program, V. D.; Volcano Observatories, L. A.

    2014-12-01

    We describe results of cooperative work that advanced volcanic monitoring and risk reduction. The USGS-USAID Volcano Disaster Assistance Program (VDAP) was initiated in 1986 after disastrous lahars during the 1985 eruption of Nevado del Ruiz dramatizedthe need to advance international capabilities in volcanic monitoring, eruption forecasting and hazard communication. For the past 28 years, VDAP has worked with our partners to improve observatories, strengthen monitoring networks, and train observatory personnel. We highlight a few of the many accomplishments by Latin American volcano observatories. Advances in monitoring, assessment and communication, and lessons learned from the lahars of the 1985 Nevado del Ruiz eruption and the 1994 Paez earthquake enabled the Servicio Geológico Colombiano to issue timely, life-saving warnings for 3 large syn-eruptive lahars at Nevado del Huila in 2007 and 2008. In Chile, the 2008 eruption of Chaitén prompted SERNAGEOMIN to complete a national volcanic vulnerability assessment that led to a major increase in volcano monitoring. Throughout Latin America improved seismic networks now telemeter data to observatories where the decades-long background rates and types of seismicity have been characterized at over 50 volcanoes. Standardization of the Earthworm data acquisition system has enabled data sharing across international boundaries, of paramount importance during both regional tectonic earthquakes and during volcanic crises when vulnerabilities cross international borders. Sharing of seismic forecasting methods led to the formation of the international organization of Latin American Volcano Seismologists (LAVAS). LAVAS courses and other VDAP training sessions have led to international sharing of methods to forecast eruptions through recognition of precursors and to reduce vulnerabilities from all volcano hazards (flows, falls, surges, gas) through hazard assessment, mapping and modeling. Satellite remote sensing data

  6. Eso's Situation in Chile

    Science.gov (United States)

    1995-02-01

    ESO, the European Southern Observatory, in reply to questions raised by the international media, as well as an ongoing debate about the so-called "Paranal case" in Chilean newspapers, would like to make a number of related observations concerning its status and continued operation in that country [1]. THE ESO OBSERVATORY SITES IN CHILE The European Southern Observatory, an international organisation established and supported by eight European countries, has been operating more than 30 years in the Republic of Chile. Here ESO maintains one of the world's prime astronomical observatories on the La Silla mountain in the southern part of the Atacama desert. This location is in the Fourth Chilean Region, some 600 km north of Santiago de Chile. In order to protect the La Silla site against dust and light pollution from possible future mining industries, roads and settlements, ESO early acquired the territory around this site. It totals about 825 sq. km and has effectively contributed to the preservation of its continued, excellent "astronomical" quality. Each year, more than 500 astronomers from European countries, Chile and elsewhere profit from this when they come to La Silla to observe with one or more of the 15 telescopes now located there. In 1987, the ESO Council [2] decided to embark upon one of the most prestigious and technologically advanced projects ever conceived in astronomy, the Very Large Telescope (VLT). It will consist of four interconnected 8.2-metre telescopes and will become the largest optical telescope in the world when it is ready. It is safe to predict that many exciting discoveries will be made with this instrument, and it will undoubtedly play a very important role in our exploration of the distant universe and its many mysteries during the coming decades. THE VLT AND PARANAL In order to find the best site for the VLT, ESO performed a thorough investigation of many possible mountain tops, both near La Silla and in Northern Chile. They showed

  7. Establishment, test and evaluation of a prototype volcano surveillance system

    Science.gov (United States)

    Ward, P. L.; Eaton, J. P.; Endo, E.; Harlow, D.; Marquez, D.; Allen, R.

    1973-01-01

    A volcano-surveillance system utilizing 23 multilevel earthquake counters and 6 biaxial borehole tiltmeters is being installed and tested on 15 volcanoes in 4 States and 4 foreign countries. The purpose of this system is to give early warning when apparently dormant volcanoes are becoming active. The data are relayed through the ERTS-Data Collection System to Menlo Park for analysis. Installation was completed in 1972 on the volcanoes St. Augustine and Iliamna in Alaska, Kilauea in Hawaii, Baker, Rainier and St. Helens in Washington, Lassen in California, and at a site near Reykjavik, Iceland. Installation continues and should be completed in April 1973 on the volcanoes Santiaguito, Fuego, Agua and Pacaya in Guatemala, Izalco in El Salvador and San Cristobal, Telica and Cerro Negro in Nicaragua.

  8. Cook Inlet and Kenai Peninsula, Alaska ESI: VOLCANOS (Volcano Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains the locations of volcanos in Cook Inlet and Kenai Peninsula, Alaska. Vector points in the data set represent the location of the volcanos....

  9. Effects of Volcanoes on the Natural Environment

    Science.gov (United States)

    Mouginis-Mark, Peter J.

    2005-01-01

    The primary focus of this project has been on the development of techniques to study the thermal and gas output of volcanoes, and to explore our options for the collection of vegetation and soil data to enable us to assess the impact of this volcanic activity on the environment. We originally selected several volcanoes that have persistent gas emissions and/or magma production. The investigation took an integrated look at the environmental effects of a volcano. Through their persistent activity, basaltic volcanoes such as Kilauea (Hawaii) and Masaya (Nicaragua) contribute significant amounts of sulfur dioxide and other gases to the lower atmosphere. Although primarily local rather than regional in its impact, the continuous nature of these eruptions means that they can have a major impact on the troposphere for years to decades. Since mid-1986, Kilauea has emitted about 2,000 tonnes of sulfur dioxide per day, while between 1995 and 2000 Masaya has emotted about 1,000 to 1,500 tonnes per day (Duffel1 et al., 2001; Delmelle et al., 2002; Sutton and Elias, 2002). These emissions have a significant effect on the local environment. The volcanic smog ("vog" ) that is produced affects the health of local residents, impacts the local ecology via acid rain deposition and the generation of acidic soils, and is a concern to local air traffic due to reduced visibility. Much of the work that was conducted under this NASA project was focused on the development of field validation techniques of volcano degassing and thermal output that could then be correlated with satellite observations. In this way, we strove to develop methods by which not only our study volcanoes, but also volcanoes in general worldwide (Wright and Flynn, 2004; Wright et al., 2004). Thus volcanoes could be routinely monitored for their effects on the environment. The selected volcanoes were: Kilauea (Hawaii; 19.425 N, 155.292 W); Masaya (Nicaragua; 11.984 N, 86.161 W); and Pods (Costa Rica; 10.2OoN, 84.233 W).

  10. Volcano-tectonic interactions at Sabancaya and other Peruvian volcanoes revealed by InSAR and seismicity

    Science.gov (United States)

    Jay, J.; Pritchard, M. E.; Aron, F.; Delgado, F.; Macedo, O.; Aguilar, V.

    2013-12-01

    southeast. We investigate a possible relationship between the seismicity and the subsidence and find that the swarm generates a stress field which may encourage the opening of fractures oriented parallel to both the elongation of the subsidence signal and the trend of regional faults. Thus, we hypothesize that the Ticsani swarm triggered the subsidence to the southeast by allowing migration of hydrothermal fluids through cracks, similar to the volcanic subsidence observed in southern Chile following the 2010 Maule earthquake and in Japan following the 2011 Tohoku earthquake, though other explanations for the subsidence cannot be ruled out. A noteworthy null result of our InSAR survey is the lack of deformation at Ubinas volcano, one of the most active volcanoes in Peru, even spanning its 2006 eruption.

  11. 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)

  12. Volcano geodesy in the Cascade arc, USA

    Science.gov (United States)

    Poland, Michael; Lisowski, Michael; Dzurisin, Daniel; Kramer, Rebecca; McLay, Megan; Pauk, Benjamin

    2017-01-01

    Experience during historical time throughout the Cascade arc and the lack of deep-seated deformation prior to the two most recent eruptions of Mount St. Helens might lead one to infer that Cascade volcanoes are generally quiescent and, specifically, show no signs of geodetic change until they are about to erupt. Several decades of geodetic data, however, tell a different story. Ground- and space-based deformation studies have identified surface displacements at five of the 13 major Cascade arc volcanoes that lie in the USA (Mount Baker, Mount St. Helens, South Sister, Medicine Lake, and Lassen volcanic center). No deformation has been detected at five volcanoes (Mount Rainier, Mount Hood, Newberry Volcano, Crater Lake, and Mount Shasta), and there are not sufficient data at the remaining three (Glacier Peak, Mount Adams, and Mount Jefferson) for a rigorous assessment. In addition, gravity change has been measured at two of the three locations where surveys have been repeated (Mount St. Helens and Mount Baker show changes, while South Sister does not). Broad deformation patterns associated with heavily forested and ice-clad Cascade volcanoes are generally characterized by low displacement rates, in the range of millimeters to a few centimeters per year, and are overprinted by larger tectonic motions of several centimeters per year. Continuous GPS is therefore the best means of tracking temporal changes in deformation of Cascade volcanoes and also for characterizing tectonic signals so that they may be distinguished from volcanic sources. Better spatial resolution of volcano deformation can be obtained through the use of campaign GPS, semipermanent GPS, and interferometric synthetic aperture radar observations, which leverage the accumulation of displacements over time to improve signal to noise. Deformation source mechanisms in the Cascades are diverse and include magma accumulation and withdrawal, post-emplacement cooling of recent volcanic deposits, magmatic

  13. Volcano geodesy in the Cascade arc, USA

    Science.gov (United States)

    Poland, Michael P.; Lisowski, Michael; Dzurisin, Daniel; Kramer, Rebecca; McLay, Megan; Pauk, Ben

    2017-08-01

    Experience during historical time throughout the Cascade arc and the lack of deep-seated deformation prior to the two most recent eruptions of Mount St. Helens might lead one to infer that Cascade volcanoes are generally quiescent and, specifically, show no signs of geodetic change until they are about to erupt. Several decades of geodetic data, however, tell a different story. Ground- and space-based deformation studies have identified surface displacements at five of the 13 major Cascade arc volcanoes that lie in the USA (Mount Baker, Mount St. Helens, South Sister, Medicine Lake, and Lassen volcanic center). No deformation has been detected at five volcanoes (Mount Rainier, Mount Hood, Newberry Volcano, Crater Lake, and Mount Shasta), and there are not sufficient data at the remaining three (Glacier Peak, Mount Adams, and Mount Jefferson) for a rigorous assessment. In addition, gravity change has been measured at two of the three locations where surveys have been repeated (Mount St. Helens and Mount Baker show changes, while South Sister does not). Broad deformation patterns associated with heavily forested and ice-clad Cascade volcanoes are generally characterized by low displacement rates, in the range of millimeters to a few centimeters per year, and are overprinted by larger tectonic motions of several centimeters per year. Continuous GPS is therefore the best means of tracking temporal changes in deformation of Cascade volcanoes and also for characterizing tectonic signals so that they may be distinguished from volcanic sources. Better spatial resolution of volcano deformation can be obtained through the use of campaign GPS, semipermanent GPS, and interferometric synthetic aperture radar observations, which leverage the accumulation of displacements over time to improve signal to noise. Deformation source mechanisms in the Cascades are diverse and include magma accumulation and withdrawal, post-emplacement cooling of recent volcanic deposits, magmatic

  14. Organizational changes at Earthquakes & Volcanoes

    Science.gov (United States)

    Gordon, David W.

    1992-01-01

    Primary responsibility for the preparation of Earthquakes & Volcanoes within the Geological Survey has shifted from the Office of Scientific Publications to the Office of Earthquakes, Volcanoes, and Engineering (OEVE). As a consequence of this reorganization, Henry Spall has stepepd down as Science Editor for Earthquakes & Volcanoes(E&V).

  15. IDRC in Chile

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

    occupied by Morocco). SENEGAL. GUINEA BISSAU. CHILE. Santiago. %. 0. 300 km. ARGENTINA. BOLIVIA. PERU. Arica. Punta Arenas . Puerto Montt . South. Pacific. Ocean. South. Atlantic. Ocean. Antofagasta. Coquimbo. Valparaiso. Concepcíon.

  16. Copper Bioleaching in Chile

    OpenAIRE

    Juan Carlos Gentina; Fernando Acevedo

    2016-01-01

    Chile has a great tradition of producing and exporting copper. Over the last several decades, it has become the first producer on an international level. Its copper reserves are also the most important on the planet. However, after years of mineral exploitation, the ease of extracting copper oxides and ore copper content has diminished. To keep the production level high, the introduction of new technologies has become necessary. One that has been successful is bioleaching. Chile had the first...

  17. Anatomy of a volcano

    NARCIS (Netherlands)

    Hooper, A.; Wassink, J.

    2011-01-01

    The Icelandic volcano Eyjafjallajökull caused major disruption in European airspace last year. According to his co-author, Freysteinn Sigmundsson, the reconstruction published in Nature six months later by aerospace engineering researcher, Dr Andy Hooper, opens up a new direction in volcanology. “We

  18. Spying on volcanoes

    Science.gov (United States)

    Watson, Matthew

    2017-07-01

    Active volcanoes can be incredibly dangerous, especially to those who live nearby, but how do you get close enough to observe one in action? Matthew Watson explains how artificial drones are providing volcanologists with insights that could one day save human lives

  19. Improving Quality and Child Outcomes in Early Childhood Education by Redefining the Role Afforded to Teachers in Professional Development: A Continuous Quality Improvement Learning Collaborative among Public Preschools in Chile

    Science.gov (United States)

    Arbour, MaryCatherine; Yoshikawa, Hirokazu; Atwood, Sid; Duran Mellado, Francis Romina; Godoy Ossa, Felipe; Trevino Villareal, Ernesto; Snow, Catherine E.

    2016-01-01

    Based on evidence derived from studies conducted mostly in the United States, many low- and middle-income countries are investing in early childhood education (ECE), with high expectations that it will improve academic outcomes, increase human capital, promote economic growth and reduce economic inequality. In Chile, there has been a great…

  20. Geologic Map of the Summit Region of Kilauea Volcano, Hawaii

    Science.gov (United States)

    Neal, Christina A.; Lockwood, John P.

    2003-01-01

    This report consists of a large map sheet and a pamphlet. The map shows the geology, some photographs, description of map units, and correlation of map units. The pamphlet gives the full text about the geologic map. The area covered by this map includes parts of four U.S. Geological Survey 7.5' topographic quadrangles (Kilauea Crater, Volcano, Ka`u Desert, and Makaopuhi). It encompasses the summit, upper rift zones, and Koa`e Fault System of Kilauea Volcano and a part of the adjacent, southeast flank of Mauna Loa Volcano. The map is dominated by products of eruptions from Kilauea Volcano, the southernmost of the five volcanoes on the Island of Hawai`i and one of the world's most active volcanoes. At its summit (1,243 m) is Kilauea Crater, a 3 km-by-5 km collapse caldera that formed, possibly over several centuries, between about 200 and 500 years ago. Radiating away from the summit caldera are two linear zones of intrusion and eruption, the east and the southwest rift zones. Repeated subaerial eruptions from the summit and rift zones have built a gently sloping, elongate shield volcano covering approximately 1,500 km2. Much of the volcano lies under water; the east rift zone extends 110 km from the summit to a depth of more than 5,000 m below sea level; whereas the southwest rift zone has a more limited submarine continuation. South of the summit caldera, mostly north-facing normal faults and open fractures of the Koa`e Fault System extend between the two rift zones. The Koa`e Fault System is interpreted as a tear-away structure that accommodates southward movement of Kilauea's flank in response to distension of the volcano perpendicular to the rift zones.

  1. Astro Tourism in Chile | CTIO

    Science.gov (United States)

    Program PIA Program GO-FAAR Program Other Opportunities Tourism Visits to Tololo Astro tourism in Chile Tourism in Chile Information for travelers Visit Tololo Media Relations News Press Release Publications ‹› You are here CTIO Home » Outreach » Tourism » Astro Tourism in Chile Astro Tourism in

  2. Mauna Kea volcano's ongoing 18-year swarm

    Science.gov (United States)

    Wech, A.; Thelen, W. A.

    2017-12-01

    Mauna Kea is a large postshield-stage volcano that forms the highest peak on Hawaii Island. The 4,205-meter high volcano erupted most recently between 6,000 and 4,500 years ago and exhibits relatively low rates of seismicity, which are mostly tectonic in origin resulting from lithospheric flexure under the weight of the volcano. Here we identify deep repeating earthquakes occurring beneath the summit of Mauna Kea. These earthquakes, which are not part of the Hawaiian Volcano Observatory's regional network catalog, were initially detected through a systematic search for coherent seismicity using envelope cross-correlation, and subsequent analysis revealed the presence of a long-term, ongoing swarm. The events have energy concentrated at 2-7 Hz, and can be seen in filtered waveforms dating back to the earliest continuous data from a single station archived at IRIS from November 1999. We use a single-station (3 component) match-filter analysis to create a catalog of the repeating earthquakes for the past 18 years. Using two templates created through phase-weighted stacking of thousands of sta/lta-triggers, we find hundreds of thousands of M1.3-1.6 earthquakes repeating every 7-12 minutes throughout this entire time period, with many smaller events occurring in between. The earthquakes occur at 28-31 km depth directly beneath the summit within a conspicuous gap in seismicity surrounding the flanks of the volcano. Magnitudes and periodicity are remarkably stable long-term, but do exhibit slight variability and occasionally display higher variability on shorter time scales. Network geometry precludes obtaining a reliable focal mechanism, but we interpret the frequency content and hypocenters to infer a volcanic source distinct from the regional tectonic seismicity responding to the load of the island. In this model, the earthquakes may result from the slow, persistent degassing of a relic magma chamber at depth.

  3. Catalogue of Icelandic Volcanoes

    Science.gov (United States)

    Ilyinskaya, Evgenia; Larsen, Gudrún; Gudmundsson, Magnús T.; Vogfjörd, Kristin; Jonsson, Trausti; Oddsson, Björn; Reynisson, Vidir; Pagneux, Emmanuel; Barsotti, Sara; Karlsdóttir, Sigrún; Bergsveinsson, Sölvi; Oddsdóttir, Thorarna

    2017-04-01

    The Catalogue of Icelandic Volcanoes (CIV) is a newly developed open-access web resource (http://icelandicvolcanoes.is) intended to serve as an official source of information about volcanoes in Iceland for the public and decision makers. CIV contains text and graphic information on all 32 active volcanic systems in Iceland, as well as real-time data from monitoring systems in a format that enables non-specialists to understand the volcanic activity status. The CIV data portal contains scientific data on all eruptions since Eyjafjallajökull 2010 and is an unprecedented endeavour in making volcanological data open and easy to access. CIV forms a part of an integrated volcanic risk assessment project in Iceland GOSVÁ (commenced in 2012), as well as being part of the European Union funded effort FUTUREVOLC (2012-2016) on establishing an Icelandic volcano supersite. The supersite concept implies integration of space and ground based observations for improved monitoring and evaluation of volcanic hazards, and open data policy. This work is a collaboration of the Icelandic Meteorological Office, the Institute of Earth Sciences at the University of Iceland, and the Civil Protection Department of the National Commissioner of the Iceland Police, with contributions from a large number of specialists in Iceland and elsewhere.

  4. El IDRC en Chile

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

    prácticas para promover la innovación ... Estudios para Latino américa sentaron las ... Argentina, Brasil, Canadá, Chile y Colombia. ... soluciones locales innovadoras y duraderas que apuntan a proporcionar opciones y cambios a aquellos ...

  5. Checklist, diversity and distribution of testate amoebae in Chile.

    Science.gov (United States)

    Fernández, Leonardo D; Lara, Enrique; Mitchell, Edward A D

    2015-10-01

    Bringing together more than 170 years of data, this study represents the first attempt to construct a species checklist and analyze the diversity and distribution of testate amoebae in Chile, a country that encompasses the southwestern region of South America, countless islands and part of the Antarctic. In Chile, known diversity includes 416 testate amoeba taxa (64 genera, 352 infrageneric taxa), 24 of which are here reported for the first time. Species-accumulation plots show that in Chile, the number of testate amoeba species reported has been continually increasing since the mid-19th century without leveling off. Testate amoebae have been recorded in 37 different habitats, though they are more diverse in peatlands and rainforest soils. Only 11% of species are widespread in continental Chile, while the remaining 89% of the species exhibit medium or short latitudinal distribution ranges. Also, species composition of insular Chile and the Chilean Antarctic territory is a depauperated subset of that found in continental Chile. Nearly, the 10% of the species reported here are endemic to Chile and many of them are distributed only within the so-called Chilean biodiversity hotspot (ca. 25° S-47° S). These findings are here thoroughly discussed in a biogeographical and evolutionary context. Copyright © 2015 Elsevier GmbH. All rights reserved.

  6. Antarctic volcanoes: A remote but significant hazard

    Science.gov (United States)

    Geyer, Adelina; Martí, Alex; Folch, Arnau; Giralt, Santiago

    2017-04-01

    Ash emitted during explosive volcanic eruptions can be dispersed over massive areas of the globe, posing a threat to both human health and infrastructures, such as the air traffic. Some of the last eruptions occurred during this decade (e.g. 14/04/2010 - Eyjafjallajökull, Iceland; 24/05/2011-Grímsvötn, Iceland; 05/06/2011-Puyehue-Cordón Caulle, Chile) have strongly affected the air traffic in different areas of the world, leading to economic losses of billions of euros. From the tens of volcanoes located in Antarctica, at least nine are known to be active and five of them have reported volcanic activity in historical times. However, until now, no attention has been paid to the possible social, economical and environmental consequences of an eruption that would occur on high southern latitudes, perhaps because it is considered that its impacts would be minor or local, and mainly restricted to the practically inhabited Antarctic continent. We show here, as a case study and using climate models, how volcanic ash emitted during a regular eruption of one of the most active volcanoes in Antarctica, Deception Island (South Shetland Islands), could reach the African continent as well as Australia and South America. The volcanic cloud could strongly affect the air traffic not only in the region and at high southern latitudes, but also the flights connecting Africa, South America and Oceania. Results obtained are crucial to understand the patterns of volcanic ash distribution at high southern latitudes with obvious implications for tephrostratigraphical and chronological studies that provide valuable isochrones with which to synchronize palaeoclimate records. This research was partially funded by the MINECO grants VOLCLIMA (CGL2015-72629-EXP)and POSVOLDEC(CTM2016-79617-P)(AEI/FEDER, UE), the Ramón y Cajal research program (RYC-2012-11024) and the NEMOH European project (REA grant 34 agreement n° 289976).

  7. Ruiz Volcano: Preliminary report

    Science.gov (United States)

    Ruiz Volcano, Colombia (4.88°N, 75.32°W). All times are local (= GMT -5 hours).An explosive eruption on November 13, 1985, melted ice and snow in the summit area, generating lahars that flowed tens of kilometers down flank river valleys, killing more than 20,000 people. This is history's fourth largest single-eruption death toll, behind only Tambora in 1815 (92,000), Krakatau in 1883 (36,000), and Mount Pelée in May 1902 (28,000). The following briefly summarizes the very preliminary and inevitably conflicting information that had been received by press time.

  8. The 2012-2014 eruptive cycle of Copahue Volcano, Southern Andes. Magmatic-Hydrothermal system interaction and manifestations.

    Science.gov (United States)

    Morales, Sergio; Alarcón, Alex; Basualto, Daniel; Bengoa, Cintia; Bertín, Daniel; Cardona, Carlos; Córdova, Maria; Franco, Luis; Gil, Fernando; Hernandez, Erasmo; Lara, Luis; Lazo, Jonathan; Mardones, Cristian; Medina, Roxana; Peña, Paola; Quijada, Jonathan; San Martín, Juan; Valderrama, Oscar

    2015-04-01

    Copahue Volcano (COPV), in Southern Andes of Chile, is an andesitic-basaltic stratovolcano, which is located on the western margin of Caviahue Caldera. The COPV have a NE-trending fissure with 9 aligned vents, being El Agrio the main currently active vent, with ca. 400 m in diameter. The COPV is placed into an extensive hydrothermal system which has modulated its recent 2012-2014 eruptive activity, with small phreatic to phreatomagmatic eruptions and isolated weak strombolian episodes and formation of crater lakes inside the main crater. Since 2012, the Southern Andes Volcano Observatory (OVDAS) carried out the real-time monitoring with seismic broadband stations, GPS, infrasound sensors and webcams. In this work, we report pre, sin, and post-eruptive seismic activity of the last two main eruptions (Dec, 2012 and Oct, 2014) both with different seismic precursors and superficial activity, showing the second one a particularly appearance of seismic quiescence episodes preceding explosive activity, as an indicator of interaction between magmatic-hydrothermal systems. The first episode, in late 2012, was characterized by a low frequency (0.3-0.4 Hz and 1.0-1.5 Hz) continuous tremor which increased gradually from background noise level amplitude to values of reduced displacement (DR), close to 50 cm2 at the peak of the eruption, reaching an eruptive column of ~1.5 km height. After few months of recording low energy seismicity, a sequence of low frequency, repetitive and low energy seismic events arose, with a frequency of occurrence up to 300 events/hour. Also, the VLP earthquakes were added to the record probably associated with magma intrusion into a deep magmatic chamber during all stages of eruptive process, joined to the record of VT seismicity during the same period, which is located throughout the Caviahue Caldera area. Both kind of seismic patterns were again recorded in October 2014, being the precursor of the new eruptive cycle at this time as well as the

  9. 2004 Deformation of Okmok Volcano,Alaska, USA

    Science.gov (United States)

    Fournier, T. J.; Freymueller, J. T.

    2004-12-01

    Okmok Volcano is a basaltic shield volcano with a 10km diameter caldera located on Umnak Island in the Aleutian Arc, Alaska. Okmok has had frequent effusive eruptions, the latest in 1997. In 2002 the Alaska Volcano Observatory installed a seismic network and three continuous GPS stations. Two stations are located in the caldera and one is located at the base of the volcano at Fort Glenn. Because of instrumentation problems the GPS network was not fully operational until August 2003. A fourth GPS site, located on the south flank of the volcano, came online in September 2004. The three continuous GPS instruments captured a rapid inflation event at Okmok Volcano spanning 6 months from March to August 2004. The instruments give a wonderful time-series of the episode but poor spatial coverage. Modeling the deformation is accomplished by supplementing the continuous data with campaign surveys conducted in the summers of 2002, 2003 and 2004. Displacements between the 2002 and 2003 campaigns show a large inflation event between those time periods. The continuous and campaign data suggest that deformation at Okmok is characterized by short-lived rapid inflation interspersed with periods of moderate inflation. Velocities during the 2004 event reached a maximum of 31cm/yr in the vertical direction and 15cm/yr eastward at the station OKCD, compared with the pre-inflation velocities of 4cm/yr in the vertical and 2.5cm/yr southeastward. Using a Mogi point source model both prior to and during the inflation gives a source location in the center of the caldera and a depth of about 3km. The source strength rate is three times larger during the inflation event than the period preceding it. Based on the full time series of campaign and continuous GPS data, it appears that the variation in inflation rate results from changes in the magma supply rate and not from changes in the depth of the source.

  10. ESO and Chile: 10 Years of Productive Scientific Collaboration

    Science.gov (United States)

    2006-06-01

    ESO and the Government of Chile launched today the book "10 Years Exploring the Universe", written by the beneficiaries of the ESO-Chile Joint Committee. This annual fund provides grants for individual Chilean scientists, research infrastructures, scientific congresses, workshops for science teachers and astronomy outreach programmes for the public. In a ceremony held in Santiago on 19 June 2006, the European Organisation for Astronomical Research in the Southern Hemisphere (ESO) and the Chilean Ministry of Foreign Affairs marked the 10th Anniversary of the Supplementary Agreement, which granted to Chilean astronomers up to 10 percent of the total observing time on ESO telescopes. This agreement also established an annual fund for the development of astronomy, managed by the so-called "ESO-Chile Joint Committee". ESO PR Photo 21/06 ESO PR Photo 21/06 Ten Years ESO-Chile Agreement Ceremony The celebration event was hosted by ESO Director General, Dr. Catherine Cesarsky, and the Director of Special Policy for the Chilean Ministry of Foreign Affairs, Ambassador Luis Winter. "ESO's commitment is, and always will be, to promote astronomy and scientific knowledge in the country hosting our observatories", said ESO Director General, Dr. Catherine Cesarsky. "We hope Chile and Europe will continue with great achievements in this fascinating joint adventure, the exploration of the universe." On behalf of the Government of Chile, Ambassador Luis Winter outlined the historical importance of the Supplementary Agreement, ratified by the Chilean Congress in 1996. "Such is the magnitude of ESO-Chile Joint Committee that, only in 2005, this annual fund represented 8 percent of all financing sources for Chilean astronomy, including those from Government and universities", Ambassador Winter said. The ESO Representative and Head of Science in Chile, Dr. Felix Mirabel, and the appointed Chilean astronomer for the ESO-Chile Joint Committee, Dr. Leonardo Bronfman, also took part in the

  11. Spent Fuel in Chile

    International Nuclear Information System (INIS)

    López Lizana, F.

    2015-01-01

    The government has made a complete and serious study of many different aspects and possible road maps for nuclear electric power with strong emphasis on safety and energy independence. In the study, the chapter of SFM has not been a relevant issue at this early stage due to the fact that it has been left for later implementation stage. This paper deals with the options Chile might consider in managing its Spent Fuel taking into account foreign experience and factors related to safety, economics, public acceptance and possible novel approaches in spent fuel treatment. The country’s distinctiveness and past experience in this area taking into account that Chile has two research reactors which will have an influence in the design of the Spent Fuel option. (author)

  12. Eruptive viscosity and volcano morphology

    International Nuclear Information System (INIS)

    Posin, S.B.; Greeley, R.

    1988-01-01

    Terrestrial central volcanoes formed predominantly from lava flows were classified as shields, stratovolcanoes, and domes. Shield volcanoes tend to be large in areal extent, have convex slopes, and are characterized by their resemblance to inverted hellenic war shields. Stratovolcanoes have concave slopes, whereas domes are smaller and have gentle convex slopes near the vent that increase near the perimeter. In addition to these differences in morphology, several other variations were observed. The most important is composition: shield volcanoes tend to be basaltic, stratovolcanoes tend to be andesitic, and domes tend to be dacitic. However, important exceptions include Fuji, Pico, Mayon, Izalco, and Fuego which have stratovolcano morphologies but are composed of basaltic lavas. Similarly, Ribkwo is a Kenyan shield volcano composed of trachyte and Suswa and Kilombe are shields composed of phonolite. These exceptions indicate that eruptive conditions, rather than composition, may be the primary factors that determine volcano morphology. The objective of this study is to determine the relationships, if any, between eruptive conditions (viscosity, erupted volume, and effusion rate) and effusive volcano morphology. Moreover, it is the goal of this study to incorporate these relationships into a model to predict the eruptive conditions of extraterrestrial (Martian) volcanoes based on their morphology

  13. Volcanoes, Third Edition

    Science.gov (United States)

    Nye, Christopher J.

    It takes confidence to title a smallish book merely “Volcanoes” because of the impliction that the myriad facets of volcanism—chemistry, physics, geology, meteorology, hazard mitigation, and more—have been identified and addressed to some nontrivial level of detail. Robert and Barbara Decker have visited these different facets seamlessly in Volcanoes, Third Edition. The seamlessness comes from a broad overarching, interdisciplinary, professional understanding of volcanism combined with an exceptionally smooth translation of scientific jargon into plain language.The result is a book which will be informative to a very broad audience, from reasonably educated nongeologists (my mother loves it) to geology undergraduates through professional volcanologists. I bet that even the most senior professional volcanologists will learn at least a few things from this book and will find at least a few provocative discussions of subjects they know.

  14. Volcanoes in Eruption - Set 1

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The word volcano is used to refer to the opening from which molten rock and gas issue from Earth's interior onto the surface, and also to the cone, hill, or mountain...

  15. Volcanoes in Eruption - Set 2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The word volcano is used to refer to the opening from which molten rock and gas issue from Earth's interior onto the surface, and also to the cone, hill, or mountain...

  16. Volcano warning systems: Chapter 67

    Science.gov (United States)

    Gregg, Chris E.; Houghton, Bruce F.; Ewert, John W.

    2015-01-01

    Messages conveying volcano alert level such as Watches and Warnings are designed to provide people with risk information before, during, and after eruptions. Information is communicated to people from volcano observatories and emergency management agencies and from informal sources and social and environmental cues. Any individual or agency can be both a message sender and a recipient and multiple messages received from multiple sources is the norm in a volcanic crisis. Significant challenges to developing effective warning systems for volcanic hazards stem from the great diversity in unrest, eruption, and post-eruption processes and the rapidly advancing digital technologies that people use to seek real-time risk information. Challenges also involve the need to invest resources before unrest to help people develop shared mental models of important risk factors. Two populations of people are the target of volcano notifications–ground- and aviation-based populations, and volcano warning systems must address both distinctly different populations.

  17. Rule of Repression in Chile.

    Science.gov (United States)

    American Indian Journal, 1979

    1979-01-01

    This report on the current condition of the Mapuche Indians of Chile is edited from a document on the "Situation of Human Rights in Chile" and details the repressive and inhumane treatment of the largest indigenous ethnic minority in the country. (Author/RTS)

  18. Primary Medical Care in Chile

    DEFF Research Database (Denmark)

    Scarpaci, Joseph L.

    Primary medical care in Chile: accessibility under military rule [Front Cover] [Front Matter] [Title Page] Contents Tables Figures Preface Chapter 1: Introduction Chapter 2: The Restructuring of Medical Care Financing in Chile Chapter 3: Inflation and Medical Care Accessibility Chapter 4: Help......-Seeking Behavior of the Urban Poor Chapter 5: Spatial Organization and Medical Care Accessibility Chapter 6: Conclusion...

  19. GLACIERS OF THE KORYAK VOLCANO

    Directory of Open Access Journals (Sweden)

    T. M. Manevich

    2012-01-01

    Full Text Available The paper presents main glaciological characteristics of present-day glaciers located on the Koryaksky volcano. The results of fieldwork (2008–2009 and high-resolution satellite image analysis let us to specify and complete information on modern glacial complex of Koryaksky volcano. Now there are seven glaciers with total area 8.36 km2. Three of them advance, two are in stationary state and one degrades. Moreover, the paper describes the new crater glacier.

  20. Data assimilation strategies for volcano geodesy

    Science.gov (United States)

    Zhan, Yan; Gregg, Patricia M.

    2017-09-01

    Ground deformation observed using near-real time geodetic methods, such as InSAR and GPS, can provide critical information about the evolution of a magma chamber prior to volcanic eruption. Rapid advancement in numerical modeling capabilities has resulted in a number of finite element models targeted at better understanding the connection between surface uplift associated with magma chamber pressurization and the potential for volcanic eruption. Robust model-data fusion techniques are necessary to take full advantage of the numerical models and the volcano monitoring observations currently available. In this study, we develop a 3D data assimilation framework using the Ensemble Kalman Filter (EnKF) approach in order to combine geodetic observations of surface deformation with geodynamic models to investigate volcanic unrest. The EnKF sequential assimilation method utilizes disparate data sets as they become available to update geodynamic models of magma reservoir evolution. While the EnKF has been widely applied in hydrologic and climate modeling, the adaptation for volcano monitoring is in its initial stages. As such, our investigation focuses on conducting a series of sensitivity tests to optimize the EnKF for volcano applications and on developing specific strategies for assimilation of geodetic data. Our numerical experiments illustrate that the EnKF is able to adapt well to the spatial limitations posed by GPS data and the temporal limitations of InSAR, and that specific strategies can be adopted to enhance EnKF performance to improve model forecasts. Specifically, our numerical experiments indicate that: (1) incorporating additional iterations of the EnKF analysis step is more efficient than increasing the number of ensemble members; (2) the accuracy of the EnKF results are not affected by initial parameter assumptions; (3) GPS observations near the center of uplift improve the quality of model forecasts; (4) occasionally shifting continuous GPS stations to

  1. Protecting Dark Skies in Chile

    Science.gov (United States)

    Smith, R. Chris; Sanhueza, Pedro; Phillips, Mark

    2018-01-01

    Current projections indicate that Chile will host approximately 70% of the astronomical collecting area on Earth by 2030, augmenting the enormous area of ALMA with that of three next-generation optical telescopes: LSST, GMTO, and E-ELT. These cutting-edge facilities represent billions of dollars of investment in the astronomical facilities hosted in Chile. The Chilean government, Chilean astronomical community, and the international observatories in Chile have recognized that these investments are threatened by light pollution, and have formed a strong collaboration to work at managing the threats. We will provide an update on the work being done in Chile, ranging from training municipalities about new lighting regulations to exploring international recognition of the dark sky sites of Northern Chile.

  2. Chile rural electrification cooperation

    Energy Technology Data Exchange (ETDEWEB)

    Flowers, L. [National Renewable Energy Lab., Golden, CO (United States)

    1997-12-01

    The author describes a joint program to use renewables for rural electrification projects in Chile. The initial focus was in a limited part of the country, involving wind mapping, pilot project planning, training, and development of methodologies for comparative evaluations of resources. To this point three wind hybrid systems have been installed in one region, as a part of the regional private utility, and three additional projects are being designed. Additional resource assessment and training is ongoing. The author points out the difficulties in working with utilities, the importance of signed documentation, and the need to look at these programs as long term because of the time involved in introducing such new technologies.

  3. Vertical Motions of Oceanic Volcanoes

    Science.gov (United States)

    Clague, D. A.; Moore, J. G.

    2006-12-01

    Oceanic volcanoes offer abundant evidence of changes in their elevations through time. Their large-scale motions begin with a period of rapid subsidence lasting hundreds of thousands of years caused by isostatic compensation of the added mass of the volcano on the ocean lithosphere. The response is within thousands of years and lasts as long as the active volcano keeps adding mass on the ocean floor. Downward flexure caused by volcanic loading creates troughs around the growing volcanoes that eventually fill with sediment. Seismic surveys show that the overall depression of the old ocean floor beneath Hawaiian volcanoes such as Mauna Loa is about 10 km. This gross subsidence means that the drowned shorelines only record a small part of the total subsidence the islands experienced. In Hawaii, this history is recorded by long-term tide-gauge data, the depth in drill holes of subaerial lava flows and soil horizons, former shorelines presently located below sea level. Offshore Hawaii, a series of at least 7 drowned reefs and terraces record subsidence of about 1325 m during the last half million years. Older sequences of drowned reefs and terraces define the early rapid phase of subsidence of Maui, Molokai, Lanai, Oahu, Kauai, and Niihau. Volcanic islands, such as Maui, tip down toward the next younger volcano as it begins rapid growth and subsidence. Such tipping results in drowned reefs on Haleakala as deep as 2400 m where they are tipped towards Hawaii. Flat-topped volcanoes on submarine rift zones also record this tipping towards the next younger volcano. This early rapid subsidence phase is followed by a period of slow subsidence lasting for millions of years caused by thermal contraction of the aging ocean lithosphere beneath the volcano. The well-known evolution along the Hawaiian chain from high to low volcanic island, to coral island, and to guyot is due to this process. This history of rapid and then slow subsidence is interrupted by a period of minor uplift

  4. Cataloging tremor at Kilauea Volcano, Hawaii

    Science.gov (United States)

    Thelen, W. A.; Wech, A.

    2013-12-01

    Tremor is a ubiquitous seismic feature on Kilauea volcano, which emanates from at least three distinct sources. At depth, intermittent tremor and earthquakes thought to be associated with the underlying plumbing system of Kilauea (Aki and Koyanagi, 1981) occurs approximately 40 km below and 40 km SW of the summit. At the summit of the volcano, nearly continuous tremor is recorded close to a persistently degassing lava lake, which has been present since 2008. Much of this tremor is correlated with spattering at the lake surface, but tremor also occurs in the absence of spattering, and was observed at the summit of the volcano prior to the appearance of the lava lake, predominately in association with inflation/deflation events. The third known source of tremor is in the area of Pu`u `O`o, a vent that has been active since 1983. The exact source location and depth is poorly constrained for each of these sources. Consistently tracking the occurrence and location of tremor in these areas through time will improve our understanding of the plumbing geometry beneath Kilauea volcano and help identify precursory patterns in tremor leading to changes in eruptive activity. The continuous and emergent nature of tremor precludes the use of traditional earthquake techniques for automatic detection and location of seismicity. We implement the method of Wech and Creager (2008) to both detect and localize tremor seismicity in the three regions described above. The technique uses an envelope cross-correlation method in 5-minute windows that maximizes tremor signal coherency among seismic stations. The catalog is currently being built in near-realtime, with plans to extend the analysis to the past as time and continuous data availability permits. This automated detection and localization method has relatively poor depth constraints due to the construction of the envelope function. Nevertheless, the epicenters distinguish activity among the different source regions and serve as

  5. Design of smart sensing components for volcano monitoring

    Science.gov (United States)

    Xu, M.; Song, W.-Z.; Huang, R.; Peng, Y.; Shirazi, B.; LaHusen, R.; Kiely, A.; Peterson, N.; Ma, A.; Anusuya-Rangappa, L.; Miceli, M.; McBride, D.

    2009-01-01

    In a volcano monitoring application, various geophysical and geochemical sensors generate continuous high-fidelity data, and there is a compelling need for real-time raw data for volcano eruption prediction research. It requires the network to support network synchronized sampling, online configurable sensing and situation awareness, which pose significant challenges on sensing component design. Ideally, the resource usages shall be driven by the environment and node situations, and the data quality is optimized under resource constraints. In this paper, we present our smart sensing component design, including hybrid time synchronization, configurable sensing, and situation awareness. Both design details and evaluation results are presented to show their efficiency. Although the presented design is for a volcano monitoring application, its design philosophy and framework can also apply to other similar applications and platforms. ?? 2009 Elsevier B.V.

  6. Mauna Loa--history, hazards and risk of living with the world's largest volcano

    Science.gov (United States)

    Trusdell, Frank A.

    2012-01-01

    Mauna Loa on the Island Hawaiʻi is the world’s largest volcano. People residing on its flanks face many hazards that come with living on or near an active volcano, including lava flows, explosive eruptions, volcanic smog, damaging earthquakes, and local tsunami (giant seawaves). The County of Hawaiʻi (Island of Hawaiʻi) is the fastest growing County in the State of Hawaii. Its expanding population and increasing development mean that risk from volcano hazards will continue to grow. U.S. Geological Survey (USGS) scientists at the Hawaiian Volcano Observatory (HVO) closely monitor and study Mauna Loa Volcano to enable timely warning of hazardous activity and help protect lives and property.

  7. [Eugenic abortion could explain the lower infant mortality in Cuba compared to that in Chile].

    Science.gov (United States)

    Donoso S, Enrique; Carvajal C, Jorge A

    2012-08-01

    Cuba and Chile have the lower infant mortality rates of Latin America. Infant mortality rate in Cuba is similar to that of developed countries. Chilean infant mortality rate is slightly higher than that of Cuba. To investigate if the lower infant mortality rate in Cuba, compared to Chile, could be explained by eugenic abortion, considering that abortion is legal in Cuba but not in Chile. We compared total and congenital abnormalities related infant mortality in Cuba and Chile during 2008, based on vital statistics of both countries. In 2008, infant mortality rates in Chile were significantly higher than those of Cuba (7.8 vs. 4.7 per 1,000 live born respectively, odds ratio (OR) 1.67; 95% confidence intervals (Cl) 1.52-1.83). Congenital abnormalities accounted for 33.8 and 19.2% of infant deaths in Chile and Cuba, respectively. Discarding infant deaths related to congenital abnormalities, infant mortality rate continued to be higher in Chile than in Cuba (5.19 vs. 3.82 per 1000 live born respectively, OR 1.36; 95%CI 1.221.52). Considering that antenatal diagnosis is widely available in both countries, but abortion is legal in Cuba but not in Chile, we conclude that eugenic abortion may partially explain the lower infant mortality rate observed in Cuba compared to that observed in Chile.

  8. Forensic psychiatry in Chile.

    Science.gov (United States)

    St Denis, Emily E; Sepúlveda, Enrique; Téllez, Carlos; Arboleda-Flórez, Julio; Stuart, Heather; Lam, Miu

    2012-01-01

    Mental disorders are among the most prevalent of chronic disorders, and a high prevalence of these disorders has been consistently found in jails and prisons. This study was a retrospective case series that described the population of adults charged with a criminal offense who were court ordered to undergo a psychiatric assessment within the Medical Legal Service in Santiago, Chile from 2005 to 2006. Characteristics were explored in order to better understand this population in light of the recent reforms in the judicial and health systems of Chile. Ninety percent of sampled individuals were male, primarily between the ages of 18-39 years. Seventy percent of the evaluations came from the pre-reformed judicial system and 30% were from the reformed system. Approximately 63% of evaluated offenders were considered to have a psychiatric pathology, the most common being the personality disorders. Of the evaluated offenders, approximately 84% were considered by a psychiatrist to be criminally responsible for their crime, 7% were regarded as having diminished criminal responsibility, 4% were considered to be not criminally responsible for their crime, and 4% were cases where criminal responsibility was not applicable. Profession status, municipality of residence, type of residence, ICD-10 diagnosis, treatment recommendation, and criminal responsibility were found to be significantly different between male and female evaluated offenders. Results from this investigation will contribute to knowledge about forensic psychiatry and mental health in Latin America, and will hopefully pave the way for more research and international comparisons. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Geophysical Observations Supporting Research of Magmatic Processes at Icelandic Volcanoes

    Science.gov (United States)

    Vogfjörd, Kristín. S.; Hjaltadóttir, Sigurlaug; Roberts, Matthew J.

    2010-05-01

    Magmatic processes at volcanoes on the boundary between the European and North American plates in Iceland are observed with in-situ multidisciplinary geophysical networks owned by different national, European or American universities and research institutions, but through collaboration mostly operated by the Icelandic Meteorological Office. The terrestrial observations are augmented by space-based interferometric synthetic aperture radar (InSAR) images of the volcanoes and their surrounding surface. Together this infrastructure can monitor magma movements in several volcanoes from the base of the crust up to the surface. The national seismic network is sensitive enough to detect small scale seismicity deep in the crust under some of the voclanoes. High resolution mapping of this seismicity and its temporal progression has been used to delineate the track of the magma as it migrates upwards in the crust, either to form an intrusion at shallow levels or to reach the surface in an eruption. Broadband recording has also enabled capturing low frequency signals emanating from magmatic movements. In two volcanoes, Eyjafjallajökull and Katla, just east of the South Iceland Seismic Zone (SISZ), seismicity just above the crust-mantle boundary has revealed magma intruding into the crust from the mantle below. As the magma moves to shallower levels, the deformation of the Earth‘s surface is captured by geodetic systems, such as continuous GPS networks, (InSAR) images of the surface and -- even more sensitive to the deformation -- strain meters placed in boreholes around 200 m below the Earth‘s surface. Analysis of these signals can reveal the size and shape of the magma as well as the temporal evolution. At near-by Hekla volcano flanking the SISZ to the north, where only 50% of events are of M>1 compared to 86% of earthquakes in Eyjafjallajökull, the sensitivity of the seismic network is insufficient to detect the smallest seismicity and so the volcano appears less

  10. Modeling volcano growth on the Island of Hawaii: deep-water perspectives

    Science.gov (United States)

    Lipman, Peter W.; Calvert, Andrew T.

    2013-01-01

    Recent ocean-bottom geophysical surveys, dredging, and dives, which complement surface data and scientific drilling at the Island of Hawaii, document that evolutionary stages during volcano growth are more diverse than previously described. Based on combining available composition, isotopic age, and geologically constrained volume data for each of the component volcanoes, this overview provides the first integrated models for overall growth of any Hawaiian island. In contrast to prior morphologic models for volcano evolution (preshield, shield, postshield), growth increasingly can be tracked by age and volume (magma supply), defining waxing alkalic, sustained tholeiitic, and waning alkalic stages. Data and estimates for individual volcanoes are used to model changing magma supply during successive compositional stages, to place limits on volcano life spans, and to interpret composite assembly of the island. Volcano volumes vary by an order of magnitude; peak magma supply also varies sizably among edifices but is challenging to quantify because of uncertainty about volcano life spans. Three alternative models are compared: (1) near-constant volcano propagation, (2) near-equal volcano durations, (3) high peak-tholeiite magma supply. These models define inconsistencies with prior geodynamic models, indicate that composite growth at Hawaii peaked ca. 800–400 ka, and demonstrate a lower current rate. Recent age determinations for Kilauea and Kohala define a volcano propagation rate of 8.6 cm/yr that yields plausible inception ages for other volcanoes of the Kea trend. In contrast, a similar propagation rate for the less-constrained Loa trend would require inception of Loihi Seamount in the future and ages that become implausibly large for the older volcanoes. An alternative rate of 10.6 cm/yr for Loa-trend volcanoes is reasonably consistent with ages and volcano spacing, but younger Loa volcanoes are offset from the Kea trend in age-distance plots. Variable magma flux

  11. The added value of time-variable microgravimetry to the understanding of how volcanoes work

    Science.gov (United States)

    Carbone, Daniele; Poland, Michael; Greco, Filippo; Diament, Michel

    2017-01-01

    During the past few decades, time-variable volcano gravimetry has shown great potential for imaging subsurface processes at active volcanoes (including some processes that might otherwise remain “hidden”), especially when combined with other methods (e.g., ground deformation, seismicity, and gas emissions). By supplying information on changes in the distribution of bulk mass over time, gravimetry can provide information regarding processes such as magma accumulation in void space, gas segregation at shallow depths, and mechanisms driving volcanic uplift and subsidence. Despite its potential, time-variable volcano gravimetry is an underexploited method, not widely adopted by volcano researchers or observatories. The cost of instrumentation and the difficulty in using it under harsh environmental conditions is a significant impediment to the exploitation of gravimetry at many volcanoes. In addition, retrieving useful information from gravity changes in noisy volcanic environments is a major challenge. While these difficulties are not trivial, neither are they insurmountable; indeed, creative efforts in a variety of volcanic settings highlight the value of time-variable gravimetry for understanding hazards as well as revealing fundamental insights into how volcanoes work. Building on previous work, we provide a comprehensive review of time-variable volcano gravimetry, including discussions of instrumentation, modeling and analysis techniques, and case studies that emphasize what can be learned from campaign, continuous, and hybrid gravity observations. We are hopeful that this exploration of time-variable volcano gravimetry will excite more scientists about the potential of the method, spurring further application, development, and innovation.

  12. Global Volcano Mortality Risks and Distribution

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Volcano Mortality Risks and Distribution is a 2.5 minute grid representing global volcano mortality risks. The data set was constructed using historical...

  13. Fires in Chile

    Science.gov (United States)

    2002-01-01

    On February 5, 2002, the dense smoke from numerous forest fires stretched out over the Pacific Ocean about 400 miles south of Santiago, Chile. This true-color Moderate-resolution Imaging Spectroradiometer (MODIS) image shows the fires, which are located near the city of Temuco. The fires are indicated with red dots (boxes in the high-resolution imagery). The fires were burning near several national parks and nature reserves in an area of the Chilean Andes where tourism is very popular. Southeast of the fires, the vegetation along the banks of the Rio Negro in Argentina stands out in dark green. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  14. Global Volcano Model

    Science.gov (United States)

    Sparks, R. S. J.; Loughlin, S. C.; Cottrell, E.; Valentine, G.; Newhall, C.; Jolly, G.; Papale, P.; Takarada, S.; Crosweller, S.; Nayembil, M.; Arora, B.; Lowndes, J.; Connor, C.; Eichelberger, J.; Nadim, F.; Smolka, A.; Michel, G.; Muir-Wood, R.; Horwell, C.

    2012-04-01

    Over 600 million people live close enough to active volcanoes to be affected when they erupt. Volcanic eruptions cause loss of life, significant economic losses and severe disruption to people's lives, as highlighted by the recent eruption of Mount Merapi in Indonesia. The eruption of Eyjafjallajökull, Iceland in 2010 illustrated the potential of even small eruptions to have major impact on the modern world through disruption of complex critical infrastructure and business. The effects in the developing world on economic growth and development can be severe. There is evidence that large eruptions can cause a change in the earth's climate for several years afterwards. Aside from meteor impact and possibly an extreme solar event, very large magnitude explosive volcanic eruptions may be the only natural hazard that could cause a global catastrophe. GVM is a growing international collaboration that aims to create a sustainable, accessible information platform on volcanic hazard and risk. We are designing and developing an integrated database system of volcanic hazards, vulnerability and exposure with internationally agreed metadata standards. GVM will establish methodologies for analysis of the data (eg vulnerability indices) to inform risk assessment, develop complementary hazards models and create relevant hazards and risk assessment tools. GVM will develop the capability to anticipate future volcanism and its consequences. NERC is funding the start-up of this initiative for three years from November 2011. GVM builds directly on the VOGRIPA project started as part of the GRIP (Global Risk Identification Programme) in 2004 under the auspices of the World Bank and UN. Major international initiatives and partners such as the Smithsonian Institution - Global Volcanism Program, State University of New York at Buffalo - VHub, Earth Observatory of Singapore - WOVOdat and many others underpin GVM.

  15. Relative chronology of Martian volcanoes

    International Nuclear Information System (INIS)

    Landheim, R.; Barlow, N.G.

    1991-01-01

    Impact cratering is one of the major geological processes that has affected the Martian surface throughout the planet's history. The frequency of craters within particular size ranges provides information about the formation ages and obliterative episodes of Martian geologic units. The Barlow chronology was extended by measuring small craters on the volcanoes and a number of standard terrain units. Inclusions of smaller craters in units previously analyzed by Barlow allowed for a more direct comparison between the size-frequency distribution data for volcanoes and established chronology. During this study, 11,486 craters were mapped and identified in the 1.5 to 8 km diameter range in selected regions of Mars. The results are summarized in this three page report and give a more precise estimate of the relative chronology of the Martian volcanoes. Also, the results of this study lend further support to the increasing evidence that volcanism has been a dominant geologic force throughout Martian history

  16. Systematic radon survey over active volcanoes

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, J.L.; Monnin, M.; Garcia Vindas, J.R. [Centre National de la Recherche Cientifique, Montpellier (France). Lab. GBE; Ricard, L.P.; Staudacher, T. [Observatoire Volcanologique Du Pitou de la Fournaise, La Plaine des Cafres (France)

    1999-08-01

    Data obtained since 1993 on Costa Rica volcanos are presented and radon anomalies recorded before the eruption of the Irazu volcano (December 8, 1994) are discussed. The Piton de la Fournaise volcano is inactive since mid 1992. The influence of the external parameters on the radon behaviour is studied and the type of perturbations induced on short-term measurements are individuate.

  17. The Varve Record of Puyehue Lake (Meridional Chile), AD 1412-2002 .

    Science.gov (United States)

    Boes, X.; Arnaud, F.; Fagel, N.

    2004-12-01

    Puyehue Lake is located in the Southern Volcanic Zone of Chile (Southern Lake District, 40°S). This monomictic lake is under the influence of the oceanic winter polar front (WPF) and constitutes a powerful sedimentary archive for paleoenvironmental reconstruction. The underflow (PUI) and interflow (PUII) coring sites were selected by a high resolution seismic survey (RUG). The sedimentation is driven by the annual blooms of diatoms in association with thermal lake cycles. For each site, one short core (50-60 cm) is analyzed by continuous cover of thin sections for varve counting and chronology for the AD 1412-2002 time window. The varve chronology is constrained by 210Pb,137Cs sedimentation rate estimates, and by the AD 1960 Valdivia'seismite. The sediment laminations are especially emphasized by the continuous grey-scale measurements from thin sections. Detrital clayey material characterizes the dark levels, and biogenic diatom mud defines the light levels. Varve counting is derived from the occurrence of light layers, i.e. formed at the end of winter after nutrient turn-over. In both cores, the grey-scale is influenced by instantaneous tephra layers related to the regional volcanic activity (Puyehue and Cordon Caulle volcanoes). For instance, in PUII, we identify major historical eruptions (AD 1921, 1837, 1790, 1564, and 1544) in accordance with the varve age model. In addition, we measure the total varve thickness. Lower than 500 µm until AD 1780, the varve thickness gradually increases by a factor of four in PUII. The first period suggests a decrease of lake productivity, in agreement with a cooling. The age fits with the end of Little Ice Age in Southern America. Between AD 1780-2002, the thicker varves could be driven by a reinforcement of the WPF since the 19e century. Our local observations require further investigations to be extrapolated over regional or global scale.

  18. Multiphase modelling of mud volcanoes

    Science.gov (United States)

    Colucci, Simone; de'Michieli Vitturi, Mattia; Clarke, Amanda B.

    2015-04-01

    Mud volcanism is a worldwide phenomenon, classically considered as the surface expression of piercement structures rooted in deep-seated over-pressured sediments in compressional tectonic settings. The release of fluids at mud volcanoes during repeated explosive episodes has been documented at numerous sites and the outflows resemble the eruption of basaltic magma. As magma, the material erupted from a mud volcano becomes more fluid and degasses while rising and decompressing. The release of those gases from mud volcanism is estimated to be a significant contributor both to fluid flux from the lithosphere to the hydrosphere, and to the atmospheric budget of some greenhouse gases, particularly methane. For these reasons, we simulated the fluid dynamics of mud volcanoes using a newly-developed compressible multiphase and multidimensional transient solver in the OpenFOAM framework, taking into account the multicomponent nature (CH4, CO2, H2O) of the fluid mixture, the gas exsolution during the ascent and the associated changes in the constitutive properties of the phases. The numerical model has been tested with conditions representative of the LUSI, a mud volcano that has been erupting since May 2006 in the densely populated Sidoarjo regency (East Java, Indonesia), forcing the evacuation of 40,000 people and destroying industry, farmland, and over 10,000 homes. The activity of LUSI mud volcano has been well documented (Vanderkluysen et al., 2014) and here we present a comparison of observed gas fluxes and mud extrusion rates with the outcomes of numerical simulations. Vanderkluysen, L.; Burton, M. R.; Clarke, A. B.; Hartnett, H. E. & Smekens, J.-F. Composition and flux of explosive gas release at LUSI mud volcano (East Java, Indonesia) Geochem. Geophys. Geosyst., Wiley-Blackwell, 2014, 15, 2932-2946

  19. El proceso emprendedor en Chile

    OpenAIRE

    José Miguel Benavente

    2004-01-01

    Este estudio analiza los factores que afectan en forma positiva y negativa el proceso de creación de emprendimientos dinámicos en Chile. Se basa en una encuesta a 200 empresas jóvenes, la cual es parte de una muestra de casi 2000 empresas de América Latina. El presente estudio se enfoca básicamente en el segmento de nuevos emprendimientos existentes en Chile.

  20. Evolution of ice-dammed proglacial lakes in Última Esperanza, Chile: implications from the late-glacial R1 eruption of Reclús volcano, Andean Austral Volcanic Zone Evolución de lagos proglaciales embalsados por hielo en Última Esperanza, Chile: Implicancias de la explosión volcánica tardiglacial R1 del volcán Reclús, Zona Volcánica Austral Andina

    Directory of Open Access Journals (Sweden)

    Charles R Stern

    2011-01-01

    Full Text Available Newly described outerops, excavations and sediment cores from the region of Última Esperanza, Magallanes, contain tephra derived from the large late-glacial explosive Rl eruption of the Reclús volcano in the Andean Austral Volcanic Zone. New radiocarbon dates associated to these deposits refine previous estimates of the age, to 14.9 cal kyrs BP (12,670±240 14C yrs BP, and volume, to >5 km³, of this tephra. The geographic and stratigraphic distribution of Rl also place constraints on the evolution of the ice-dammed proglacial lake that existed east of the cordillera in this area between the termination of the Last Glacial Maximum (LGM and the Holocene. This proglacial lake generated wave-cut terraces, and also caves, such as the Cueva de Milodón, along the highest prominent terrace. The current elevation of these terraces depends on the total amount of post-glacial isostatic rebound, which is unknown. Due to differential rebound, the highest prominent lake terraces decrease in height from west-to-east, from -170 m a.s.l. on Península Antonio Varas west of Seno Ultima Esperanza, to-150 m a.s.l. aroundLago Sofía, anddownto-125 m a.s.l. along their easternmost margin. The presence of thick deposits of Rl tephra in some of the caves around Lago Sofía implies that the proglacial lake had already dropped below its highest level prior to the time of this eruption, and, in fact, even earlier, prior to 16.1 cal kyrs BP (13,560±180 14C yrs BP, when land mammals first oceupied these caves. The depositional environment of Rl in a core from Dumestre bog suggests that the lake level was in fact 70 m a.s.l. until 12.8 cal kyrs BP (10,695±40 14C yrs BP. However, a 14.2 cal kyrs BP (12,125±85 14C yrs BF Mylodon pelvis from a nearby site, located at only -7 m a.s.l., suggests that the lake could have emptied, for at least a brief period, to this low level at this time. This latter datum, combined with the lack of any prominent terraces between the

  1. Alaska volcanoes guidebook for teachers

    Science.gov (United States)

    Adleman, Jennifer N.

    2011-01-01

    Alaska’s volcanoes, like its abundant glaciers, charismatic wildlife, and wild expanses inspire and ignite scientific curiosity and generate an ever-growing source of questions for students in Alaska and throughout the world. Alaska is home to more than 140 volcanoes, which have been active over the last 2 million years. About 90 of these volcanoes have been active within the last 10,000 years and more than 50 of these have been active since about 1700. The volcanoes in Alaska make up well over three-quarters of volcanoes in the United States that have erupted in the last 200 years. In fact, Alaska’s volcanoes erupt so frequently that it is almost guaranteed that an Alaskan will experience a volcanic eruption in his or her lifetime, and it is likely they will experience more than one. It is hard to imagine a better place for students to explore active volcanism and to understand volcanic hazards, phenomena, and global impacts. Previously developed teachers’ guidebooks with an emphasis on the volcanoes in Hawaii Volcanoes National Park (Mattox, 1994) and Mount Rainier National Park in the Cascade Range (Driedger and others, 2005) provide place-based resources and activities for use in other volcanic regions in the United States. Along the lines of this tradition, this guidebook serves to provide locally relevant and useful resources and activities for the exploration of numerous and truly unique volcanic landscapes in Alaska. This guidebook provides supplemental teaching materials to be used by Alaskan students who will be inspired to become educated and prepared for inevitable future volcanic activity in Alaska. The lessons and activities in this guidebook are meant to supplement and enhance existing science content already being taught in grade levels 6–12. Correlations with Alaska State Science Standards and Grade Level Expectations adopted by the Alaska State Department of Education and Early Development (2006) for grades six through eleven are listed at

  2. Geology of El Chichon volcano, Chiapas, Mexico

    Science.gov (United States)

    Duffield, Wendell A.; Tilling, Robert I.; Canul, Rene

    1984-03-01

    The (pre-1982) 850-m-high andesitic stratovolcano El Chichón, active during Pleistocene and Holocene time, is located in rugged, densely forested terrain in northcentral Chiapas, México. The nearest neighboring Holocene volcanoes are 275 km and 200 km to the southeast and northwest, respectively. El Chichón is built on Tertiary siltstone and sandstone, underlain by Cretaceous dolomitic limestone; a 4-km-deep bore hole near the east base of the volcano penetrated this limestone and continued 770 m into a sequence of Jurassic or Cretaceous evaporitic anhydrite and halite. The basement rocks are folded into generally northwest-trending anticlines and synclines. El Chichón is built over a small dome-like structure superposed on a syncline, and this structure may reflect cumulative deformation related to growth of a crustal magma reservoir beneath the volcano. The cone of El Chichón consists almost entirely of pyroclastic rocks. The pre-1982 cone is marked by a 1200-m-diameter (explosion?) crater on the southwest flank and a 1600-m-diameter crater apparently of similar origin at the summit, a lava dome partly fills each crater. The timing of cone and dome growth is poorly known. Field evidence indicates that the flank dome is older than the summit dome, and K-Ar ages from samples high on the cone suggest that the flank dome is older than about 276,000 years. At least three pyroclastic eruptions have occurred during the past 1250 radiocarbon years. Nearly all of the pyroclastic and dome rocks are moderately to highly porphyritic andesite, with plagioclase, hornblende and clinopyroxene the most common phenocrysts. Geologists who mapped El Chichón in 1980 and 1981 warned that the volcano posed a substantial hazard to the surrounding region. This warning was proven to be prophetic by violent eruptions that occurred in March and April of 1982. These eruptions blasted away nearly all of the summit dome, blanketed the surrounding region with tephra, and sent pyroclastic

  3. Conservation and sustainable use in the buffer zone of the moorland of Chiles, Department of Nariño

    Directory of Open Access Journals (Sweden)

    Jorge Anibal Maya Pantoja

    2011-05-01

    Full Text Available this project was able to determine the need of strengthen the indigenous communities in Chiles, so they claim to nature, by prioritizing projects that can generate income to low income people which allow to decrease the negative impact on the moorland. the Chiles moorland is inhabited by 3.637 people of which 100% belong to indigenous council with Sisben level one, sidewalks nearby that are part of it are Calera, Chiles, Cristo Rey, and Marpi Nazate, the moorland of Chile has 5.626 hectares, soils formed entirely of pyroclastic material from volcanoes: Chiles, Azufral, Cumbal, their use is destined in a 3.8% for agriculture, 8.2% for pasture, devoted to dairy farming and a 78% is considered protected area without any use. Human activities that threaten the integrity of this ecosystem, are deforestation (8 ha/year and burning (10 ha/ year, 70% of the population of the indigenous reserve of Chiles perceives an average monthly income below $ 50,000 (USD$20 from activities such as farmers, laborers, masons, carpenters, among others. Every year, the agricultural frontier is expanding into 10 ha/year, 120 to 150 trees / ha per year of species such as yellow, oak, quasar, colla, capulicillo are cut and around 30 families residing in Marpi and Nazate are dedicated to charcoal production, using around 80 trees / year.

  4. Laboratory volcano geodesy

    Science.gov (United States)

    Færøvik Johannessen, Rikke; Galland, Olivier; Mair, Karen

    2014-05-01

    intrusion can be excavated and photographed from several angles to compute its 3D shape with the same photogrammetry method. Then, the surface deformation pattern can be directly compared with the shape of underlying intrusion. This quantitative dataset is essential to quantitatively test and validate classical volcano geodetic models.

  5. Stratigraphy, sedimentology, and geothermal reservoir potential of the volcaniclastic Cura-Mallín succession at Lonquimay, Chile

    Science.gov (United States)

    Pedroza, Viviana; Le Roux, Jacobus P.; Gutiérrez, Néstor M.; Vicencio, Vladimir E.

    2017-08-01

    The Tolhuaca Volcano near Lonquimay in south-central Chile has been the subject of several studies due to its geothermal manifestations, but little is known about the stratigraphy and reservoir potential of the Cura-Mallín Formation forming its basement. Field work and U-Pb dating of detrital zircons allow us to redefine this succession as the Cura-Mallín Group, consisting of the volcano-sedimentary Guapitrío Formation, sedimentary Río Pedregoso Formation, and volcano-sedimentary Mitrauquén Formation. The Río Pedregoso Formation can be subdivided into three formal units, namely the Quilmahue Member, Rucañanco Member, and Bío-Bío Member. The base of the Quilmahue Member interfingers laterally with the base of the Guapitrío Formation, for which a previous K/Ar date of 22.0 ± 0.9 Ma was apparently discarded by the original authors. However, this date is consistent with the stratigraphic position of the Quilmahue Member and new zircon dates from the overlying units, also coinciding with the initiation of an extensional phase in the Bíobío-Aluminé Basin. Deposition of the Quilmahue Member continued throughout the early Miocene, as confirmed by dates of 17.5 Ma reported by previous authors and 16.5 Ma obtained in this study. The Rucañanco Member was deposited during the Serravalian around 12.6 Ma, whereas the Bío-Bío Member was dated at the Serravalian-Tortonian limit (11.6 Ma). Although all three members were deposited in a fluvio-lacustrine environment, they were dominated respectively by flood plains with crevasse splays, lake margins with distributary mouth bars and Gilbert-type deltas, and distal braided and meandering rivers. Whereas the Quilmahue Member was deposited during basin extension, the Rucañanco Member was formed during a period of basin inversion and compression. Temporary tectonic quiescence during deposition of the Bío-Bío Member allowed denudation of the landscape, but around 9.5 Ma tectonism was renewed again during deposition of

  6. What Happened to Our Volcano?

    Science.gov (United States)

    Mangiante, Elaine Silva

    2006-01-01

    In this article, the author presents an investigative approach to "understanding Earth changes." The author states that students were familiar with earthquakes and volcanoes in other regions of the world but never considered how the land beneath their feet had experienced changes over time. Here, their geology unit helped them understand…

  7. Foreshocks and aftershocks locations of the 2014 Pisagua, N. Chile earthquake: history of a megathrust earthquake nucleation

    Science.gov (United States)

    Fuenzalida Velasco, Amaya; Rietbrock, Andreas; Tavera, Hernando; Ryder, Isabelle; Ruiz, Sergio; Thomas, Reece; De Angelis, Silvio; Bondoux, Francis

    2015-04-01

    The April 2014 Mw 8.1 Pisagua earthquake occurred in the Northern Chile seismic gap: a region of the South American subduction zone lying between Arica city and the Mejillones Peninsula. It is believed that this part of the subduction zone has not experienced a large earthquake since 1877. Thanks to the identification of this seismic gap, the north of Chile was well instrumented before the Pisagua earthquake, including the Integrated Plate boundary Observatory Chile (IPOC) network and the Chilean local network installed by the Centro Sismologico Nacional (CSN). These instruments were able to record the full foreshock and aftershock sequences, allowing a unique opportunity to study the nucleation process of large megathrust earthquakes. To improve azimuthal coverage of the Pisagua seismic sequence, after the earthquake, in collaboration with the Instituto Geofisico del Peru (IGP) we installed a temporary seismic network in south of Peru. The network comprised 12 short-period stations located in the coastal area between Moquegua and Tacna and they were operative from 1st May 2014. We also installed three stations on the slopes of the Ticsiani volcano to monitor any possible change in volcanic activity following the Pisagua earthquake. In this work we analysed the continuous seismic data recorded by CSN and IPOC networks from 1 March to 30 June to obtain the catalogue of the sequence, including foreshocks and aftershocks. Using an automatic algorithm based in STA/LTA we obtained the picks for P and S waves. Association in time and space defined the events and computed an initial location using Hypo71 and the 1D local velocity model. More than 11,000 events were identified with this method for the whole period, but we selected the best resolved events that include more than 7 observed arrivals with at least 2 S picks of them, to relocate these events using NonLinLoc software. For the main events of the sequence we carefully estimate event locations and we obtained

  8. Galactic Super-volcano in Action

    Science.gov (United States)

    2010-08-01

    A galactic "super-volcano" in the massive galaxy M87 is erupting and blasting gas outwards, as witnessed by NASA's Chandra X-ray Observatory and NSF's Very Large Array. The cosmic volcano is being driven by a giant black hole in the galaxy's center and preventing hundreds of millions of new stars from forming. Astronomers studying this black hole and its effects have been struck by the remarkable similarities between it and a volcano in Iceland that made headlines earlier this year. At a distance of about 50 million light years, M87 is relatively close to Earth and lies at the center of the Virgo cluster, which contains thousands of galaxies. M87's location, coupled with long observations over Chandra's lifetime, has made it an excellent subject for investigations of how a massive black hole impacts its environment. "Our results show in great detail that supermassive black holes have a surprisingly good control over the evolution of the galaxies in which they live," said Norbert Werner of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University and the SLAC National Accelerator Laboratory, who led one of two papers describing the study. "And it doesn't stop there. The black hole's reach extends ever farther into the entire cluster, similar to how one small volcano can affect practically an entire hemisphere on Earth." The cluster surrounding M87 is filled with hot gas glowing in X-ray light, which is detected by Chandra. As this gas cools, it can fall toward the galaxy's center where it should continue to cool even faster and form new stars. However, radio observations with the Very Large Array suggest that in M87 jets of very energetic particles produced by the black hole interrupt this process. These jets lift up the relatively cool gas near the center of the galaxy and produce shock waves in the galaxy's atmosphere because of their supersonic speed. The scientists involved in this research have found the interaction of this cosmic

  9. [Protomedicato in Chile].

    Science.gov (United States)

    Pérez-Olea, J

    1991-09-01

    In 1566 Alonso de Villadiego was nominated by the Chilean Cabildo as "Adviser and Examiner in Surgery". By means of this edict, the Spanish Crown paralleled its classical health organization, inspired in rules coming from XIIIth century. The Hospital del Socorro was the focal point of these activities. It turned to be prosperous under the administration of "San Juan de Dios" monks (1617), who rebaptized the Hospital with their name. During the administration of the "Universidad de San Felipe" (1738-1839), the Protomedicato followed the standards imposed by the Cahir of Prima Medicina. Domingo Nevin, Frenchman, and José Antonio Ríos, Chilean, were the first and the last doctors in charge of this task. Ríos conducted the antivariolic campaign, supervised the "Midwifery Law" and controlled the medical and paramedical practice. Afterwards, the Institution plunged into a profound crisis to reflourish in 1833 when it was incorporated within the structure of the School of Medicine. Blest, Cox, Bustillos and Moran were the architects of its splendour. With the foundation of the Universidad de Chile in 1842, its Faculty of Medicine took over the Protomedicato functions. The Institution came to an end in 1892.

  10. Country watch: Chile.

    Science.gov (United States)

    Montoya Leiva, M

    1996-01-01

    Servicio Paz y Justicia (SERPAJ) is a nongovernmental organization (NGO) established in Chile in 1977. It supports fundamental human dignity and rights by fighting discrimination and exclusion based upon individual differences. SERPAJ promotes training, organization, and the political participation of community members as part of the democratic process, working mainly with the at risk women, street children, and youth of Santiago's working-class neighborhoods. Groups participate in workshops and training courses on human rights and development, civic education, and methods of non-violent community action. In 1987, SERPAJ-Sur Oriente began to include the topic of sexuality and AIDS/STDs in courses training working-class women as community human rights agents. The NGO is therefore one of the first mainstream Chilean human rights organizations to incorporate HIV/AIDS issues. A basic facts brochure was developed, followed by a pilot education project developed in one neighborhood which was then systematically replicated in other neighborhoods. The comments of some people who have participated in SERPAJ workshops are presented.

  11. complejidad en Chile

    Directory of Open Access Journals (Sweden)

    Miguel Alejandro Bustamante-Ubilla

    2015-01-01

    Full Text Available El presente estudio tiene por objetivo caracterizar el clima organizacional al interior de 2 hospitales dealta complejidad de Chile, determinando las dimensiones más y menos influyentes. Para su desarrollose aplicó un cuestionario que consta de 71 variables agrupadas en 14 dimensiones a una muestra de561 funcionarios. La interpretación de los resultados se realizó a través del análisis del valor prome-dio estandarizado y su confiabilidad ratificada mediante el alfa de Cronbach. A partir de lo anterior, sedeterminó que las dimensiones que influyen por encima del promedio fueron: identidad, motivaciónlaboral y responsabilidad; en tanto que las dimensiones que muestran un nivel de impacto por debajodel promedio resultaron ser: equipo y distribución de personas y material, administración del conflictoy comunicación.© 2015 Universidad ICESI. Publicado por Elsevier España, S.L.U. Este es un artículo Open Access bajo lalicencia CC BY (http://creativecommons.org/licenses/by/4.0/.

  12. Morphometry of terrestrial shield volcanoes

    Science.gov (United States)

    Grosse, Pablo; Kervyn, Matthieu

    2018-03-01

    Shield volcanoes are described as low-angle edifices built primarily by the accumulation of successive lava flows. This generic view of shield volcano morphology is based on a limited number of monogenetic shields from Iceland and Mexico, and a small set of large oceanic islands (Hawaii, Galápagos). Here, the morphometry of 158 monogenetic and polygenetic shield volcanoes is analyzed quantitatively from 90-meter resolution SRTM DEMs using the MORVOLC algorithm. An additional set of 24 lava-dominated 'shield-like' volcanoes, considered so far as stratovolcanoes, are documented for comparison. Results show that there is a large variation in shield size (volumes from 0.1 to > 1000 km3), profile shape (height/basal width (H/WB) ratios mostly from 0.01 to 0.1), flank slope gradients (average slopes mostly from 1° to 15°), elongation and summit truncation. Although there is no clear-cut morphometric difference between shield volcanoes and stratovolcanoes, an approximate threshold can be drawn at 12° average slope and 0.10 H/WB ratio. Principal component analysis of the obtained database enables to identify four key morphometric descriptors: size, steepness, plan shape and truncation. Hierarchical cluster analysis of these descriptors results in 12 end-member shield types, with intermediate cases defining a continuum of morphologies. The shield types can be linked in terms of growth stages and shape evolution, related to (1) magma composition and rheology, effusion rate and lava/pyroclast ratio, which will condition edifice steepness; (2) spatial distribution of vents, in turn related to the magmatic feeding system and the tectonic framework, which will control edifice plan shape; and (3) caldera formation, which will condition edifice truncation.

  13. Iridium emissions from Hawaiian volcanoes

    International Nuclear Information System (INIS)

    Finnegan, D.L.; Zoller, W.H.; Miller, T.M.

    1988-01-01

    Particle and gas samples were collected at Mauna Loa volcano during and after its eruption in March and April, 1984 and at Kilauea volcano in 1983, 1984, and 1985 during various phases of its ongoing activity. In the last two Kilauea sampling missions, samples were collected during eruptive activity. The samples were collected using a filterpack system consisting of a Teflon particle filter followed by a series of 4 base-treated Whatman filters. The samples were analyzed by INAA for over 40 elements. As previously reported in the literature, Ir was first detected on particle filters at the Mauna Loa Observatory and later from non-erupting high temperature vents at Kilauea. Since that time Ir was found in samples collected at Kilauea and Mauna Loa during fountaining activity as well as after eruptive activity. Enrichment factors for Ir in the volcanic fumes range from 10,000 to 100,000 relative to BHVO. Charcoal impregnated filters following a particle filter were collected to see if a significant amount of the Ir was in the gas phase during sample collection. Iridium was found on charcoal filters collected close to the vent, no Ir was found on the charcoal filters. This indicates that all of the Ir is in particulate form very soon after its release. Ratios of Ir to F and Cl were calculated for the samples from Mauna Loa and Kilauea collected during fountaining activity. The implications for the KT Ir anomaly are still unclear though as Ir was not found at volcanoes other than those at Hawaii. Further investigations are needed at other volcanoes to ascertain if basaltic volcanoes other than hot spots have Ir enrichments in their fumes

  14. Iridium emissions from Hawaiian volcanoes

    Science.gov (United States)

    Finnegan, D. L.; Zoller, W. H.; Miller, T. M.

    1988-01-01

    Particle and gas samples were collected at Mauna Loa volcano during and after its eruption in March and April, 1984 and at Kilauea volcano in 1983, 1984, and 1985 during various phases of its ongoing activity. In the last two Kilauea sampling missions, samples were collected during eruptive activity. The samples were collected using a filterpack system consisting of a Teflon particle filter followed by a series of 4 base-treated Whatman filters. The samples were analyzed by INAA for over 40 elements. As previously reported in the literature, Ir was first detected on particle filters at the Mauna Loa Observatory and later from non-erupting high temperature vents at Kilauea. Since that time Ir was found in samples collected at Kilauea and Mauna Loa during fountaining activity as well as after eruptive activity. Enrichment factors for Ir in the volcanic fumes range from 10,000 to 100,000 relative to BHVO. Charcoal impregnated filters following a particle filter were collected to see if a significant amount of the Ir was in the gas phase during sample collection. Iridium was found on charcoal filters collected close to the vent, no Ir was found on the charcoal filters. This indicates that all of the Ir is in particulate form very soon after its release. Ratios of Ir to F and Cl were calculated for the samples from Mauna Loa and Kilauea collected during fountaining activity. The implications for the KT Ir anomaly are still unclear though as Ir was not found at volcanoes other than those at Hawaii. Further investigations are needed at other volcanoes to ascertain if basaltic volcanoes other than hot spots have Ir enrichments in their fumes.

  15. Collaborative Monitoring and Hazard Mitigation at Fuego Volcano, Guatemala

    Science.gov (United States)

    Lyons, J. J.; Bluth, G. J.; Rose, W. I.; Patrick, M.; Johnson, J. B.; Stix, J.

    2007-05-01

    A portable, digital sensor network has been installed to closely monitor changing activity at Fuego volcano, which takes advantage of an international collaborative effort among Guatemala, U.S. and Canadian universities, and the Peace Corps. The goal of this effort is to improve the understanding shallow internal processes, and consequently to more effectively mitigate volcanic hazards. Fuego volcano has had more than 60 historical eruptions and nearly-continuous activity make it an ideal laboratory to study volcanic processes. Close monitoring is needed to identify base-line activity, and rapidly identify and disseminate changes in the activity which might threaten nearby communities. The sensor network is comprised of a miniature DOAS ultraviolet spectrometer fitted with a system for automated plume scans, a digital video camera, and two seismo-acoustic stations and portable dataloggers. These sensors are on loan from scientists who visited Fuego during short field seasons and donated use of their sensors to a resident Peace Corps Masters International student from Michigan Technological University for extended data collection. The sensor network is based around the local volcano observatory maintained by Instituto National de Sismologia, Vulcanologia, Metrologia e Hidrologia (INSIVUMEH). INSIVUMEH provides local support and historical knowledge of Fuego activity as well as a secure location for storage of scientific equipment, data processing, and charging of the batteries that power the sensors. The complete sensor network came online in mid-February 2007 and here we present preliminary results from concurrent gas, seismic, and acoustic monitoring of activity from Fuego volcano.

  16. Taking the pulse of Mars via dating of a plume-fed volcano.

    Science.gov (United States)

    Cohen, Benjamin E; Mark, Darren F; Cassata, William S; Lee, Martin R; Tomkinson, Tim; Smith, Caroline L

    2017-10-03

    Mars hosts the solar system's largest volcanoes. Although their size and impact crater density indicate continued activity over billions of years, their formation rates are poorly understood. Here we quantify the growth rate of a Martian volcano by 40 Ar/ 39 Ar and cosmogenic exposure dating of six nakhlites, meteorites that were ejected from Mars by a single impact event at 10.7 ± 0.8 Ma (2σ). We find that the nakhlites sample a layered volcanic sequence with at least four discrete eruptive events spanning 93 ± 12 Ma (1416 ± 7 Ma to 1322 ± 10 Ma (2σ)). A non-radiogenic trapped 40 Ar/ 36 Ar value of 1511 ± 74 (2σ) provides a precise and robust constraint for the mid-Amazonian Martian atmosphere. Our data show that the nakhlite-source volcano grew at a rate of ca. 0.4-0.7 m Ma -1 -three orders of magnitude slower than comparable volcanoes on Earth, and necessitating that Mars was far more volcanically active earlier in its history.Mars hosts the solar system's largest volcanoes, but their formation rates remain poorly constrained. Here, the authors have measured the crystallization and ejection ages of meteorites from a Martian volcano and find that its growth rate was much slower than analogous volcanoes on Earth.

  17. Recent Inflation of Kilauea Volcano

    Science.gov (United States)

    Miklius, A.; Poland, M.; Desmarais, E.; Sutton, A.; Orr, T.; Okubo, P.

    2006-12-01

    Over the last three years, geodetic monitoring networks and satellite radar interferometry have recorded substantial inflation of Kilauea's magma system, while the Pu`u `O`o eruption on the east rift zone has continued unabated. Combined with the approximate doubling of carbon dioxide emission rates at the summit during this period, these observations indicate that the magma supply rate to the volcano has increased. Since late 2003, the summit area has risen over 20 cm, and a 2.5 km-long GPS baseline across the summit area has extended almost half a meter. The center of inflation has been variable, with maximum uplift shifting from an area near the center of the caldera to the southeastern part of the caldera in 2004-2005. In 2006, the locus of inflation shifted again, to the location of the long-term magma reservoir in the southern part of the caldera - the same area that had subsided more than 1.5 meters during the last 23 years of the ongoing eruption. In addition, the southwest rift zone reversed its long-term trend of subsidence and began uplifting in early 2006. The east rift zone has shown slightly accelerated rates of extension, but with a year-long hiatus following the January 2005 south flank aseismic slip event. Inflation rates have varied greatly. Accelerated rates of extension and uplift in early 2005 and 2006 were also associated with increased seismicity. Seismicity occurred not only at inflation centers, but was also triggered on the normal faulting area northwest of the caldera and the strike-slip faulting area in the upper east rift zone. In early 2006, at about the time that we started recording uplift on the southwest rift zone, the rate of earthquakes extending from the summit into the southwest rift zone at least quadrupled. The most recent previous episode of inflation at Kilauea, in 2002, may have resulted from reduced lava- transport capacity, as it was associated with decreased outflow at the eruption site. In contrast, eruption volumes

  18. HIV ISSUES AND MAPUCHES IN CHILE

    Science.gov (United States)

    Cianelli, Rosina; Ferrer, Lilian; Cabieses, Báltica; Araya, Alejandra; Matsumoto, Cristina; Miner, Sarah

    2015-01-01

    Chile is a country with an incipient HIV epidemic. Just as in other countries, disadvantaged groups in Chile are contributing to the increased incidence of the disease. The Mapuche indigenous population is one such group that has been affected by the spread of HIV. However, no prevention programs are tailored to the culturally specific needs of this community. In recognition of this discrepancy, an academic-community partnership was formed to develop an HIV educational module for a Mapuche community. The module was developed for use as part of an already established health-related program. The aims of the module were to identify perceptions about HIV among Mapuches and present information specific to HIV and its prevention. Focus was placed on cultural sensitivity. The module was carried out in connection with a first-aid course in an attempt to increase effectiveness of the intervention by working jointly with an established community program. Sixteen (16) Mapuches participated voluntarily and demonstrated some knowledge regarding HIV, but they lacked an overall understanding as to how it is transmitted and why prevention strategies are affective. Participants correctly identified sexual contact as a means of transmission, but when asked why, one person stated, “I just know it, I read it.” There were significant barriers to communication within the group, secondary to cultural practices related to age and gender. Major obstacles in controlling HIV are the lack of prevention strategies targeted to disadvantaged groups. The module developed for this intervention was the first effort of the Academic Community Partnership established between the Pontificia Universidad Católica de Chile and the Mapuche group around HIV prevention. Continued collaboration between academia and affected communities as well as incorporating HIV information into established programs are effective strategies for delivering prevention information to disadvantaged populations and for

  19. Modernitet og forbrugskultur i Chile

    DEFF Research Database (Denmark)

    Cristoffanini, Pablo Rolando

    2012-01-01

    I de sidste årtier er Chile blevet et egentligt forbrugersamfund. Udbredelsen af forbrugskulturen og forbrugerismen er centrale fænomener i chilenernes dagligliv og har nået et omfang, som har konsekvenser for de borgere, der ikke kan deltage fuldt ud heri, noget som er typisk for et samfund med en...... ujævn økonomisk udvikling og med store sociale forskelle. Denne proces er ikke et produkt af en stille, fredelig og naturlig samfundsudvikling, således som magteliten og de toneangivende intellektuelle i Chile har fremstillet det. Som jeg vil vise, er skabelsen af et egentlig forbrugssamfund knyttet til...... til i dag. Ifølge disse er Chile blevet et moderne samfund netop i kraft af, at Chile er et ægte forbrugersamfund med alt, hvad dette indebærer, såvel materielt som symbolsk. For det tredje er billedet af Chile som en ”supermoderne” nation i den latinamerikanske kontekst en udbredt forestilling hos...

  20. Strategies for the implementation of a European Volcano Observations Research Infrastructure

    Science.gov (United States)

    Puglisi, Giuseppe

    2015-04-01

    Active volcanic areas in Europe constitute a direct threat to millions of people on both the continent and adjacent islands. Furthermore, eruptions of "European" volcanoes in overseas territories, such as in the West Indies, an in the Indian and Pacific oceans, can have a much broader impacts, outside Europe. Volcano Observatories (VO), which undertake volcano monitoring under governmental mandate and Volcanological Research Institutions (VRI; such as university departments, laboratories, etc.) manage networks on European volcanoes consisting of thousands of stations or sites where volcanological parameters are either continuously or periodically measured. These sites are equipped with instruments for geophysical (seismic, geodetic, gravimetric, electromagnetic), geochemical (volcanic plumes, fumaroles, groundwater, rivers, soils), environmental observations (e.g. meteorological and air quality parameters), including prototype deployment. VOs and VRIs also operate laboratories for sample analysis (rocks, gases, isotopes, etc.), near-real time analysis of space-borne data (SAR, thermal imagery, SO2 and ash), as well as high-performance computing centres; all providing high-quality information on the current status of European volcanoes and the geodynamic background of the surrounding areas. This large and high-quality deployment of monitoring systems, focused on a specific geophysical target (volcanoes), together with the wide volcanological phenomena of European volcanoes (which cover all the known volcano types) represent a unique opportunity to fundamentally improve the knowledge base of volcano behaviour. The existing arrangement of national infrastructures (i.e. VO and VRI) appears to be too fragmented to be considered as a unique distributed infrastructure. Therefore, the main effort planned in the framework of the EPOS-PP proposal is focused on the creation of services aimed at providing an improved and more efficient access to the volcanological facilities

  1. International Uranium Resources Evaluation Project (IUREP) national favourability studies: Chile

    International Nuclear Information System (INIS)

    1977-08-01

    Chile has an area of 740,760 square kilometers. The capital is Santiago. The country is 4,183 km. long and ranges from 22.5 to about 354 km. in width. Its chief topographic features para]lei each other - the Coastal Range, Andes Mountains and Central Valley. The Coastal Range rises to 2,130 meters in the north, but averages from 610 to 700 meters high generally. The range plunges into the Pacific Ocean far south of Valparaiso and reappears in the southern archipelagic islands. The Andes extend along nearly the entire length of Chile and contain 100 volcanoes. Andean peaks range mostly from 3,000 to 6,700 meters in elevation. In southern Chile the Andes are lower, and contain about a dozen major lakes. The mountains disappear in Chilean Patagonia, but reappear at Cape Horn. The Central Valley lies between the Coastal Range and the Andes, being best defined in the midland region as a 64 to 72 km sloping plain. It is the Chilean heartland with three-quarters of the country's population. Salt basins are found over much of northern Chile in the very arid desert, while the region south of the Gulf of Reloncavi consists of unpopulated islands, fjords, channels and heavily forested mountains. The Strait of Magellan, the Tierra del Fuego archipelago and a flat grassland area make up the extreme southern end of the country. Much of Chile is subject to flash floods, earthquakes, volcanic eruptions, landslides and avalanches. In September 1976 the Comision Chilena de Energia Nuclear (CCEN) was given exclusive rights to negotiate contracts with private companies for the exploration, development and mining of uranium and other radioactive minerals. The new law provides the CCEN with considerable flexibility in the terms of the contracts. Pre-964 owners of uranium deposits may reach agreements with foreign companies to mine the uranium, but since 1964 all uranium has belonged to the state. Uranium produced in the country can only be exported after Chile's needs have been met. The

  2. Internationalization of SMES: business opportunities in Chile

    OpenAIRE

    Correia, João Filipe Amado

    2016-01-01

    The main goal of this study is to identify the main business opportunities in Chile, legal advantages in the business perspective and entry strategies for small and medium sized enterprises (SMEs). The methodology used was qualitative, by conducting several interviews with chamber of commerce representative from Portugal in Chile and Chile in Portugal, several young entrepreneurs from different nations operating in Chile, the CEO of a Spanish company that decided to not internationalize to...

  3. Honey as a bioindicator of arsenic contamination due to volcanic and mining activities in Chile

    OpenAIRE

    Bastías, José M; Jambon, Philippe; Muñoz, Ociel; Manquián, Nimia; Bahamonde, Patricia; Neira, Miguel

    2013-01-01

    The content of heavy metals in honey is indicative of natural or anthropogenic pollution and has therefore been proposed as a feasible bioindicator for arsenic contamination in different regions of Chile. Total arsenic (t-As) and inorganic As (i-As) concentrations were determined in 227 samples of honey harvested during the years 2007, 2008, and 2009 in the areas of San Pedro de Atacama, Atacama, Chiloé, and Futaleufú, with the last town located 156 km from the Chaitén Volcano (latest eruptio...

  4. Database for the Geologic Map of the Summit Region of Kilauea Volcano, Hawaii

    Science.gov (United States)

    Dutton, Dillon R.; Ramsey, David W.; Bruggman, Peggy E.; Felger, Tracey J.; Lougee, Ellen; Margriter, Sandy; Showalter, Patrick; Neal, Christina A.; Lockwood, John P.

    2007-01-01

    INTRODUCTION The area covered by this map includes parts of four U.S. Geological Survey (USGS) 7.5' topographic quadrangles (Kilauea Crater, Volcano, Ka`u Desert, and Makaopuhi). It encompasses the summit, upper rift zones, and Koa`e Fault System of Kilauea Volcano and a part of the adjacent, southeast flank of Mauna Loa Volcano. The map is dominated by products of eruptions from Kilauea Volcano, the southernmost of the five volcanoes on the Island of Hawai`i and one of the world's most active volcanoes. At its summit (1,243 m) is Kilauea Crater, a 3 km-by-5 km collapse caldera that formed, possibly over several centuries, between about 200 and 500 years ago. Radiating away from the summit caldera are two linear zones of intrusion and eruption, the east and the southwest rift zones. Repeated subaerial eruptions from the summit and rift zones have built a gently sloping, elongate shield volcano covering approximately 1,500 km2. Much of the volcano lies under water: the east rift zone extends 110 km from the summit to a depth of more than 5,000 m below sea level; whereas, the southwest rift zone has a more limited submarine continuation. South of the summit caldera, mostly north-facing normal faults and open fractures of the Koa`e Fault System extend between the two rift zones. The Koa`e Fault System is interpreted as a tear-away structure that accommodates southward movement of Kilauea's flank in response to distension of the volcano perpendicular to the rift zones. This digital release contains all the information used to produce the geologic map published as USGS Geologic Investigations Series I-2759 (Neal and Lockwood, 2003). The main component of this digital release is a geologic map database prepared using ArcInfo GIS. This release also contains printable files for the geologic map and accompanying descriptive pamphlet from I-2759.

  5. Wildfires in Chile: A review

    Science.gov (United States)

    Úbeda, Xavier; Sarricolea, Pablo

    2016-11-01

    This paper reviews the literature examining the wildfire phenomenon in Chile. Since ancient times, Chile's wildfires have shaped the country's landscape, but today, as in many other parts of the world, the fire regime - pattern, frequency and intensity - has grown at an alarming rate. In 2014, > 8000 fires were responsible for burning c. 130,000 ha, making it the worst year in Chile's recent history. The reasons for this increase appear to be the increment in the area planted with flammable species; the rejection of these landscape modifications on the part of local communities that target these plantations in arson attacks; and, the adoption of intensive forest management practices resulting in the accumulation of a high fuel load. These trends have left many native species in a precarious situation and forest plantation companies under considerable financial pressure. An additional problem is posed by fires at the wildland urban interface (WUI), threatening those inhabitants that live in Chile's most heavily populated cities. The prevalence of natural fires in Chile; the relationship between certain plant species and fire in terms of seed germination strategies and plant adaptation; the relationship between fire and invasive species; and, the need for fire prevention systems and territorial plans that include fire risk assessments are some of the key aspects discussed in this article. Several of the questions raised will require further research, including just how fire-dependent the ecosystems in Chile are, how the forest at the WUI can be better managed to prevent human and material damage, and how best to address the social controversy that pits the Mapuche population against the timber companies.

  6. Volcano geodesy: Challenges and opportunities for the 21st century

    Science.gov (United States)

    Dzurisin, D.

    2000-01-01

    Intrusions of magma beneath volcanoes deform the surrounding rock and, if the intrusion is large enough, the overlying ground surface. Numerical models generally agree that, for most eruptions, subsurface volume changes are sufficient to produce measurable deformation at the surface. Studying this deformation can help to determine the location, volume, and shape of a subsurface magma body and thus to anticipate the onset and course of an eruption. This approach has been successfully applied at many restless volcanoes, especially basaltic shields and silicic calderas, using various geodetic techniques and sensors. However, its success at many intermediate-composition strato-volcanoes has been limited by generally long repose intervals, steep terrain, and structural influences that complicate the history and shape of surface deformation. These factors have made it difficult to adequately characterize deformation in space and time at many of the world's dangerous volcanoes. Recent technological advances promise to make this task easier by enabling the acquisition of geodetic data of high spatial and temporal resolution from Earth-orbiting satellites. Synthetic aperture radar interferometry (InSAR) can image ground deformation over large areas at metre-scale resolution over time-scales of a month to a few years. Global Positioning System (GPS) stations can provide continuous information on three-dimensional ground displacements at a network of key sites -information that is especially important during volcanic crises. By using InSAR to determine the shape of the displacement field and GPS to monitor temporal changes at key sites, scientists have a much better chance to capture geodetic signals that have so far been elusive at many volcanoes. This approach has the potential to provide longer-term warnings of impending volcanic activity than is possible with other monitoring techniques.

  7. Aleutian Islands Coastal Resources Inventory and Environmental Sensitivity Maps: VOLCANOS (Volcano Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains point locations of active volcanoes as compiled by Motyka et al., 1993. Eighty-nine volcanoes with eruptive phases in the Quaternary are...

  8. Alaska - Russian Far East connection in volcano research and monitoring

    Science.gov (United States)

    Izbekov, P. E.; Eichelberger, J. C.; Gordeev, E.; Neal, C. A.; Chebrov, V. N.; Girina, O. A.; Demyanchuk, Y. V.; Rybin, A. V.

    2012-12-01

    The Kurile-Kamchatka-Alaska portion of the Pacific Rim of Fire spans for nearly 5400 km. It includes more than 80 active volcanoes and averages 4-6 eruptions per year. Resulting ash clouds travel for hundreds to thousands of kilometers defying political borders. To mitigate volcano hazard to aviation and local communities, the Alaska Volcano Observatory (AVO) and the Institute of Volcanology and Seismology (IVS), in partnership with the Kamchatkan Branch of the Geophysical Survey of the Russian Academy of Sciences (KBGS), have established a collaborative program with three integrated components: (1) volcano monitoring with rapid information exchange, (2) cooperation in research projects at active volcanoes, and (3) volcanological field schools for students and young scientists. Cooperation in volcano monitoring includes dissemination of daily information on the state of volcanic activity in neighboring regions, satellite and visual data exchange, as well as sharing expertise and technologies between AVO and the Kamchatkan Volcanic Eruption Response Team (KVERT) and Sakhalin Volcanic Eruption Response Team (SVERT). Collaboration in scientific research is best illustrated by involvement of AVO, IVS, and KBGS faculty and graduate students in mutual international studies. One of the most recent examples is the NSF-funded Partnerships for International Research and Education (PIRE)-Kamchatka project focusing on multi-disciplinary study of Bezymianny volcano in Kamchatka. This international project is one of many that have been initiated as a direct result of a bi-annual series of meetings known as Japan-Kamchatka-Alaska Subduction Processes (JKASP) workshops that we organize together with colleagues from Hokkaido University, Japan. The most recent JKASP meeting was held in August 2011 in Petropavlovsk-Kamchatsky and brought together more than 130 scientists and students from Russia, Japan, and the United States. The key educational component of our collaborative program

  9. Flank tectonics of Martian volcanoes

    International Nuclear Information System (INIS)

    Thomas, P.J.; Squyres, S.W.; Carr, M.H.

    1990-01-01

    On the flanks of Olympus Mons is a series of terraces, concentrically distributed around the caldera. Their morphology and location suggest that they could be thrust faults caused by compressional failure of the cone. In an attempt to understand the mechanism of faulting and the possible influences of the interior structure of Olympus Mons, the authors have constructed a numerical model for elastic stresses within a Martian volcano. In the absence of internal pressurization, the middle slopes of the cone are subjected to compressional stress, appropriate to the formation of thrust faults. These stresses for Olympus Mons are ∼250 MPa. If a vacant magma chamber is contained within the cone, the region of maximum compressional stress is extended toward the base of the cone. If the magma chamber is pressurized, extensional stresses occur at the summit and on the upper slopes of the cone. For a filled but unpressurized magma chamber, the observed positions of the faults agree well with the calculated region of high compressional stress. Three other volcanoes on Mars, Ascraeus Mons, Arsia Mons, and Pavonis Mons, possess similar terraces. Extending the analysis to other Martian volcanoes, they find that only these three and Olympus Mons have flank stresses that exceed the compressional failure strength of basalt, lending support to the view that the terraces on all four are thrust faults

  10. Earthquakes and Volcanic Processes at San Miguel Volcano, El Salvador, Determined from a Small, Temporary Seismic Network

    Science.gov (United States)

    Hernandez, S.; Schiek, C. G.; Zeiler, C. P.; Velasco, A. A.; Hurtado, J. M.

    2008-12-01

    The San Miguel volcano lies within the Central American volcanic chain in eastern El Salvador. The volcano has experienced at least 29 eruptions with Volcano Explosivity Index (VEI) of 2. Since 1970, however, eruptions have decreased in intensity to an average of VEI 1, with the most recent eruption occurring in 2002. Eruptions at San Miguel volcano consist mostly of central vent and phreatic eruptions. A critical challenge related to the explosive nature of this volcano is to understand the relationships between precursory surface deformation, earthquake activity, and volcanic activity. In this project, we seek to determine sub-surface structures within and near the volcano, relate the local deformation to these structures, and better understand the hazard that the volcano presents in the region. To accomplish these goals, we deployed a six station, broadband seismic network around San Miguel volcano in collaboration with researchers from Servicio Nacional de Estudios Territoriales (SNET). This network operated continuously from 23 March 2007 to 15 January 2008 and had a high data recovery rate. The data were processed to determine earthquake locations, magnitudes, and, for some of the larger events, focal mechanisms. We obtained high precision locations using a double-difference approach and identified at least 25 events near the volcano. Ongoing analysis will seek to identify earthquake types (e.g., long period, tectonic, and hybrid events) that occurred in the vicinity of San Miguel volcano. These results will be combined with radar interferometric measurements of surface deformation in order to determine the relationship between surface and subsurface processes at the volcano.

  11. The biomethane potential in Chile

    International Nuclear Information System (INIS)

    Seiffert, M.; Kaltschmitt, M.; Miranda, J.A.

    2009-01-01

    Within the last decade natural gas gained considerable importance in Chile. The contribution of natural gas within the energy system will increase in the future by predicted 3.6% annually until the year 2015. Due to limited resources within its own country, the energy system of Chile depends on natural gas imports preferential from Argentina. Therefore, the aim of several stakeholders from policy and industry is to reduce the share of imported primary energy within the overall energy system. In order to reach this goal, the use of domestic resources and particularly the utilisation of biomass as one of the most important renewable sources of energy in Chile could play an important role. Against this background, the goal of this paper is the analysis of the technical potentials of biomethane as a substitute for natural gas. For the production of biomethane the anaerobic or bio-chemical (i.e. Biogas) as well as the thermo-chemical conversion pathways (i.e. Bio-SNG) are considered. The results of this analysis show that biomass converted to biomethane is a promising energy provision option for Chile and it contributes to the reduction of greenhouse gas emissions

  12. Forest nursery management in Chile

    Science.gov (United States)

    Rene Escobar R.; Manuel Sanchez O.; Guillermo Pereira C.

    2002-01-01

    The forest economy in Chile is based on products from artificial reforestation efforts on approximately 2 million ha. From these, about 1.5 million ha (75%) are planted with Pinus radiata, 400,000 ha (20%) with species of Eucalyptus, principally E. globulus and E. nitens, and the rest (5%) composed by other...

  13. Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico.

    Science.gov (United States)

    Kraft, Kraig H; de Jesús Luna-Ruíz, José; Gepts, Paul

    2010-12-01

    Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico. The process of selecting and saving seed is the most basic and oldest of agricultural practices. In today's modern and highly capital-intensive agriculture, seeds are often treated like another chemical input. This study sought to examine seed selection and saving practices among chile farmers in Aguascalientes, Mexico, where both industrial and traditional agriculture are practiced. We observed a clear division among farmers who plant chile peppers commercially. Sixty-eight chile pepper farmers were surveyed in order to document seed selection and saving practices. Fifteen respondents (22%) planted chile peppers destined for the fresh market and all utilized purchased commercial seed of F1 hybrid varieties. Fifty-three farmers (78%) planted chiles to be dried and either saved their own or purchased seeds that others had saved and selected. Farmers who saved their own seed sought to maintain an ideotype, rather than directionally select for certain traits, much like Cleveland et al. (2000) chronicled in central Mexican maize farmers. Farmers would benefit from a participatory plant-breeding program in order to maintain productive seed stock for the continued cultivation of dried chile pepper in the state.

  14. [Health research and health technology assessment in Chile].

    Science.gov (United States)

    Espinoza, Manuel Antonio; Cabieses, Báltica; Paraje, Guillermo

    2014-01-01

    Health research is considered an essential element for the improvement of population health and it has been recommended that a share of the national health budget should be allocated to develop this field. Chile has undertaken efforts in the last decades in order to improve the governmental structure created to promote the development of health research, which has increased human resources and funding opportunities. On the other hand, the sustained economic growth of Chile in the last decades suggests that the health expenditure will maintain its increasing trend in the following years. This additional funding could be used to improve coverage of current activities performed in the health system, but also to address the incorporation of new strategies. More recently, health technology assessment (HTA) has been proposed as a process to support decisions about allocation of resources based on scientific evidence. This paper examines the relationship between the development of health research and the HTA process. First, it presents a brief diagnosis of the situation of health research in Chile. Second, it reviews the conceptual basis and the methods that account for the relationship between a HTA process and the development of health research. In particular, it emphasizes the relevance of identifying information gaps where funding additional research can be considered a good use of public resources. Finally, it discusses the challenges and possible courses of action that Chile could take in order to guarantee the continuous improvement of an articulated structure for health research and HTA.

  15. Ash and Steam, Soufriere Hills Volcano, Monserrat

    Science.gov (United States)

    2002-01-01

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

  16. K-Ar ages of the Hiruzen volcano group and the Daisen volcano

    International Nuclear Information System (INIS)

    Tsukui, Masashi; Nishido, Hirotsugu; Nagao, Keisuke.

    1985-01-01

    Seventeen volcanic rocks of the Hiruzen volcano group and the Daisen volcano, in southwest Japan, were dated by the K-Ar method to clarify the age of volcanic activity in this region and the evolution of these composite volcanoes. The eruption ages of the Hiruzen volcano group were revealed to be about 0.9 Ma to 0.5 Ma, those of the Daisen volcano to be about 1 Ma to very recent. These results are consistent with geological and paleomagnetic data of previous workers. Effusion of lavas in the area was especially vigorous at 0.5+-0.1 Ma. It was generally considered that the Hiruzen volcano group had erupted during latest Pliocene to early Quaternary and it is older than the Daisen volcano, mainly from their topographic features. However, their overlapping eruption ages and petrographical similarities of the lavas of the Hiruzen volcano group and the Daisen volcano suggest that they may be included in the Daisen volcano in a broad sense. The aphyric andesite, whose eruption age had been correlated to Wakurayama andesite (6.34+-0.19 Ma) in Matsue city and thought to be the basement of the Daisen volcano, was dated to be 0.46+-0.04 Ma. It indicates that petrographically similar aphyric andesite erupted sporadically at different time and space in the San'in district. (author)

  17. Unrest of Chiles - Cerro Negro volcanic complex: A binational Ecuador - Colombia effort

    Science.gov (United States)

    Ruiz, M. C.; Gomez, D.; Torres, R.; Cadena, O.; Mothes, P. A.; Anzieta, J. C.; Pacheco, D. A.; Bernard, B.; Acero, W.; Hidalgo, S.; Enriquez, W.; Cordova, A.

    2014-12-01

    The increasing seismic activity at the area of Chiles - Cerro Negro volcanic complex, located at the Ecuador-Colombian border, has been jointly monitored by the Instituto Geofisico - Ecuador and the Observatorio Vulcanologico y Sismologico de Pasto OVSP, a division of the Servicio Geologico Colombiano. Since April 2013, three seismic swarms have been detected in this area and more than 100.000 events are recorded since November 2013. The largest and more recent swarm has a daily average of 676 events between March and June 2014. Currently a seismic network of 8 seismic stations (5 in the Colombian and 3 in Ecuadorean side) are deployed in this area. Epicenters of more than 315 seismic events with magnitudes Ml>2.0 and 10 or more phases are located in an area 1-4 km south of Chiles volcano with shallow depths (up to 14 km). Most of events have magnitudes between 1.0 to 4.0. Nine events have magnitudes larger than 4.0 and the largest event occurred on April 30. 2014 with a local magnitude of 4.7 and inverse-transcurrent component focal mechanism. Waveforms and spectral patterns define these events as volcano-tectonic. Events with large magnitudes (above 3.0) show a very long-period component. Hot spring and deformation measurements also show signals of volcanic unrest.

  18. Geoflicks Reviewed--Films about Hawaiian Volcanoes.

    Science.gov (United States)

    Bykerk-Kauffman, Ann

    1994-01-01

    Reviews 11 films on volcanic eruptions in the United States. Films are given a one- to five-star rating and the film's year, length, source and price are listed. Top films include "Inside Hawaiian Volcanoes" and "Kilauea: Close up of an Active Volcano." (AIM)

  19. Orographic Flow over an Active Volcano

    Science.gov (United States)

    Poulidis, Alexandros-Panagiotis; Renfrew, Ian; Matthews, Adrian

    2014-05-01

    Orographic flows over and around an isolated volcano are studied through a series of numerical model experiments. The volcano top has a heated surface, so can be thought of as "active" but not erupting. A series of simulations with different atmospheric conditions and using both idealised and realistic configurations of the Weather Research and Forecast (WRF) model have been carried out. The study is based on the Soufriere Hills volcano, located on the island of Montserrat in the Caribbean. This is a dome-building volcano, leading to a sharp increase in the surface skin temperature at the top of the volcano - up to tens of degrees higher than ambient values. The majority of the simulations use an idealised topography, in order for the results to have general applicability to similar-sized volcanoes located in the tropics. The model is initialised with idealised atmospheric soundings, representative of qualitatively different atmospheric conditions from the rainy season in the tropics. The simulations reveal significant changes to the orographic flow response, depending upon the size of the temperature anomaly and the atmospheric conditions. The flow regime and characteristic features such as gravity waves, orographic clouds and orographic rainfall patterns can all be qualitatively changed by the surface heating anomaly. Orographic rainfall over the volcano can be significantly enhanced with increased temperature anomaly. The implications for the eruptive behaviour of the volcano and resulting secondary volcanic hazards will also be discussed.

  20. Socialisme i Chile efter Pinochet

    DEFF Research Database (Denmark)

    Cristoffanini, Pablo Rolando

    2008-01-01

    Chile bliver ofte præsenteret som et paradigme for resten af det latinamerikanske kontinent: Et land med høj økonomisk vækst og politisk stabilitet. Landet har endda haft to socialistiske præsidenter siden 2000, den sidste den første kvindelige præsident. Succeshistorien har en bagside: De...... socialistiske regeringer har accepteret et begrænset demokrati og videreført en nyliberal økonomisk politik, der har bragt dem på konfrontationskurs med massebevægelserne og isoleret Chile fra de andre lande i regionen, der søger integration og gensidig støøte. Udgivelsesdato: Februar...

  1. Emplacement of Holocene silicic lava flows and domes at Newberry, South Sister, and Medicine Lake volcanoes, California and Oregon

    Science.gov (United States)

    Fink, Jonathan H.; Anderson, Steven W.

    2017-07-19

    This field guide for the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) Scientific Assembly 2017 focuses on Holocene glassy silicic lava flows and domes on three volcanoes in the Cascade Range in Oregon and California: Newberry, South Sister, and Medicine Lake volcanoes. Although obsidian-rich lava flows have been of interest to geologists, archaeologists, pumice miners, and rock hounds for more than a century, many of their emplacement characteristics had not been scientifically observed until two very recent eruptions in Chile. Even with the new observations, several eruptive processes discussed in this field trip guide can only be inferred from their final products. This makes for lively debates at outcrops, just as there have been in the literature for the past 30 years.Of the three volcanoes discussed in this field guide, one (South Sister) lies along the main axis defined by major peaks of the Cascade Range, whereas the other two lie in extensional tectonic settings east of the axis. These two tectonic environments influence volcano morphology and the magmatic and volcanic processes that form silicic lava flows and domes. The geomorphic and textural features of glass-rich extrusions provide many clues about their emplacement and the magma bodies that fed them.The scope of this field guide does not include a full geologic history or comprehensive explanation of hazards associated with a particular volcano or volcanic field. The geochemistry, petrology, tectonics, and eruption history of Newberry, South Sister, and Medicine Lake volcanic centers have been extensively studied and are discussed on other field excursions. Instead, we seek to explore the structural, textural, and geochemical evolution of well-preserved individual lava flows—the goal is to understand the geologic processes, rather than the development, of a specific volcano.

  2. The 2014 eruptions of Pavlof Volcano, Alaska

    Science.gov (United States)

    Waythomas, Christopher F.; Haney, Matthew M.; Wallace, Kristi; Cameron, Cheryl E.; Schneider, David J.

    2017-12-22

    Pavlof Volcano is one of the most frequently active volcanoes in the Aleutian Island arc, having erupted more than 40 times since observations were first recorded in the early 1800s . The volcano is located on the Alaska Peninsula (lat 55.4173° N, long 161.8937° W), near Izembek National Wildlife Refuge. The towns and villages closest to the volcano are Cold Bay, Nelson Lagoon, Sand Point, and King Cove, which are all within 90 kilometers (km) of the volcano (fig. 1). Pavlof is a symmetrically shaped stratocone that is 2,518 meters (m) high, and has about 2,300 m of relief. The volcano supports a cover of glacial ice and perennial snow roughly 2 to 4 cubic kilometers (km3) in volume, which is mantled by variable amounts of tephra fall, rockfall debris, and pyroclastic-flow deposits produced during historical eruptions. Typical Pavlof eruptions are characterized by moderate amounts of ash emission, lava fountaining, spatter-fed lava flows, explosions, and the accumulation of unstable mounds of spatter on the upper flanks of the volcano. The accumulation and subsequent collapse of spatter piles on the upper flanks of the volcano creates hot granular avalanches, which erode and melt snow and ice, and thereby generate watery debris-flow and hyperconcentrated-flow lahars. Seismic instruments were first installed on Pavlof Volcano in the early 1970s, and since then eruptive episodes have been better characterized and specific processes have been documented with greater certainty. The application of remote sensing techniques, including the use of infrasound data, has also aided the study of more recent eruptions. Although Pavlof Volcano is located in a remote part of Alaska, it is visible from Cold Bay, Sand Point, and Nelson Lagoon, making distal observations of eruptive activity possible, weather permitting. A busy air-travel corridor that is utilized by a numerous transcontinental and regional air carriers passes near Pavlof Volcano. The frequency of air travel

  3. Exploring Geology on the World-Wide Web--Volcanoes and Volcanism.

    Science.gov (United States)

    Schimmrich, Steven Henry; Gore, Pamela J. W.

    1996-01-01

    Focuses on sites on the World Wide Web that offer information about volcanoes. Web sites are classified into areas of Global Volcano Information, Volcanoes in Hawaii, Volcanoes in Alaska, Volcanoes in the Cascades, European and Icelandic Volcanoes, Extraterrestrial Volcanism, Volcanic Ash and Weather, and Volcano Resource Directories. Suggestions…

  4. Geophysical Exploration on the Structure of Volcanoes: Two Case Histories

    Energy Technology Data Exchange (ETDEWEB)

    Furumoto, A. S.

    1974-01-01

    Geophysical methods of exploration were used to determine the internal structure of Koolau Volcano in Hawaii and of Rabaul Volcano in New Guinea. By use of gravity and seismic data the central vent or plug of Koolau Volcano was outlined. Magnetic data seem to indicate that the central plug is still above the Curie Point. If so, the amount of heat energy available is tremendous. As for Rabaul Volcano, it is located in a region characterized by numerous block faulting. The volcano is only a part of a large block that has subsided. Possible geothermal areas exist near the volcano but better potential areas may exist away from the volcano.

  5. Instrumentation Recommendations for Volcano Monitoring at U.S. Volcanoes Under the National Volcano Early Warning System

    Science.gov (United States)

    Moran, Seth C.; Freymueller, Jeff T.; LaHusen, Richard G.; McGee, Kenneth A.; Poland, Michael P.; Power, John A.; Schmidt, David A.; Schneider, David J.; Stephens, George; Werner, Cynthia A.; White, Randall A.

    2008-01-01

    As magma moves toward the surface, it interacts with anything in its path: hydrothermal systems, cooling magma bodies from previous eruptions, and (or) the surrounding 'country rock'. Magma also undergoes significant changes in its physical properties as pressure and temperature conditions change along its path. These interactions and changes lead to a range of geophysical and geochemical phenomena. The goal of volcano monitoring is to detect and correctly interpret such phenomena in order to provide early and accurate warnings of impending eruptions. Given the well-documented hazards posed by volcanoes to both ground-based populations (for example, Blong, 1984; Scott, 1989) and aviation (for example, Neal and others, 1997; Miller and Casadevall, 2000), volcano monitoring is critical for public safety and hazard mitigation. Only with adequate monitoring systems in place can volcano observatories provide accurate and timely forecasts and alerts of possible eruptive activity. At most U.S. volcanoes, observatories traditionally have employed a two-component approach to volcano monitoring: (1) install instrumentation sufficient to detect unrest at volcanic systems likely to erupt in the not-too-distant future; and (2) once unrest is detected, install any instrumentation needed for eruption prediction and monitoring. This reactive approach is problematic, however, for two reasons. 1. At many volcanoes, rapid installation of new ground-1. based instruments is difficult or impossible. Factors that complicate rapid response include (a) eruptions that are preceded by short (hours to days) precursory sequences of geophysical and (or) geochemical activity, as occurred at Mount Redoubt (Alaska) in 1989 (24 hours), Anatahan (Mariana Islands) in 2003 (6 hours), and Mount St. Helens (Washington) in 1980 and 2004 (7 and 8 days, respectively); (b) inclement weather conditions, which may prohibit installation of new equipment for days, weeks, or even months, particularly at

  6. Unzipping of the volcano arc, Japan

    Science.gov (United States)

    Stern, R.J.; Smoot, N.C.; Rubin, M.

    1984-01-01

    A working hypothesis for the recent evolution of the southern Volcano Arc, Japan, is presented which calls upon a northward-progressing sundering of the arc in response to a northward-propagating back-arc basin extensional regime. This model appears to explain several localized and recent changes in the tectonic and magrnatic evolution of the Volcano Arc. Most important among these changes is the unusual composition of Iwo Jima volcanic rocks. This contrasts with normal arc tholeiites typical of the rest of the Izu-Volcano-Mariana and other primitive arcs in having alkaline tendencies, high concentrations of light REE and other incompatible elements, and relatively high silica contents. In spite of such fractionated characteristics, these lavas appear to be very early manifestations of a new volcanic and tectonic cycle in the southern Volcano Arc. These alkaline characteristics and indications of strong regional uplift are consistent with the recent development of an early stage of inter-arc basin rifting in the southern Volcano Arc. New bathymetric data are presented in support of this model which indicate: 1. (1) structural elements of the Mariana Trough extend north to the southern Volcano Arc. 2. (2) both the Mariana Trough and frontal arc shoal rapidly northwards as the Volcano Arc is approached. 3. (3) rugged bathymetry associated with the rifted Mariana Trough is replaced just south of Iwo Jima by the development of a huge dome (50-75 km diameter) centered around Iwo Jima. Such uplifted domes are the immediate precursors of rifts in other environments, and it appears that a similar situation may now exist in the southern Volcano Arc. The present distribution of unrifted Volcano Arc to the north and rifted Mariana Arc to the south is interpreted not as a stable tectonic configuration but as representing a tectonic "snapshot" of an arc in the process of being rifted to form a back-arc basin. ?? 1984.

  7. Volcanoes

    Science.gov (United States)

    ... Extreme Heat Older Adults (Aged 65+) Infants and Children Chronic Medical Conditions Low Income Athletes Outdoor Workers Pets Hot Weather Tips Warning Signs and Symptoms FAQs Social Media How to Stay Cool Missouri Cooling Centers Extreme ...

  8. Common processes at unique volcanoes – a volcanological conundrum

    OpenAIRE

    Katharine eCashman; Juliet eBiggs

    2014-01-01

    An emerging challenge in modern volcanology is the apparent contradiction between the perception that every volcano is unique, and classification systems based on commonalities among volcano morphology and eruptive style. On the one hand, detailed studies of individual volcanoes show that a single volcano often exhibits similar patterns of behavior over multiple eruptive episodes; this observation has led to the idea that each volcano has its own distinctive pattern of behavior (or “personali...

  9. Estimating Sulfur Dioxide in Volcanic Plumes Using an Ultraviolet Camera. First Results from Lascar, Ollagüe and Irruputuncu Volcanoes

    Science.gov (United States)

    Geoffroy, C. A.; Amigo, A.

    2014-12-01

    Volcanic gas fluxes give important information on both the amount of degassing and magma reservoirs. In most of magmas, water vapor (H2O) and carbon dioxide (CO2) are major components of volcanic gas. However, sulfur dioxide (SO2) is one of the targets of remote sensing due to their low concentration in the environment and easy detection by ultraviolet spectroscopy. Accordingly, plume imaging using passive ultraviolet cameras is a relatively simple method to study volcanic degassing, expeditious manner and can be used up from distances of about 10 km from source of emissions. We estimated SO2 concentrations and fluxes in volcanic plumes with the ultraviolet camera Envicam-2, developed by Nicarnica Aviation, acquired by the Geological Survey of Chile (SERNAGEOMIN). The camera has filters that allow passage of ultraviolet radiation at wavelengths of interest. For determining whether there is absorption of radiation associated with the presence of SO2 the Beer-Lambert law was used for quantifying concentrations using appropriate calibration cells. SO2 emissions to the atmosphere were estimated using wind speed as an approximation to the plume transport. In this study we reported the implementation of a new methodology for using Envicam-2 and subsequent collection of SO2 concentrations and fluxes in passive degassing volcanoes. Measurements were done at Lascar, Ollagüe and Irruputuncu volcanoes, located in northern Chile. The volcanoes were chosen because of optimal atmospheric conditions for ultraviolet imaging. Results indicate concentrations within the expected ranges for three volcanoes generally between 400-1700 ppm•m. In the case of Láscar volcano, the emission rates of SO2 range from 250 to 500 tonnes/day for a same image of the plume. In particular, wind speed was determined from scaling images and are consistent with data from regional numerical models, as well as records of the meteorological stations installed at the ALMA astronomical center, located

  10. Holocene tephrostratigraphy of southern Chiloé Continental (Andean southern volcanic zone; ~43°S), Chile

    Science.gov (United States)

    Lachowycz, S.; Smith, V. C.; Pyle, D. M.; Mather, T. A.

    2012-12-01

    The eruptive history of the volcanoes in the southern part of the Andean Southern Volcanic Zone (42.5-45°S) is very poorly constrained: only several late Quaternary eruptions have been identified, mostly from study of sparse roadcuts [1]. In this study, we further constrain the Holocene explosive eruption history around 43°S by identifying and analysing tephra layers preserved in a ~3.25m long peat core from Cuesta Moraga [2], ~35km east of Yanteles volcano. Cryptotephra was extracted following the method of [3], in addition to macrotephra; owing to the vicinity of the sampling site to the tephra sources, cryptotephra was found throughout the core stratigraphy, but was sufficiently variable in concentration that discrete layers were identifiable and attributed to specific eruptions. Chemical analysis of the glass by electron microprobe shows that the tephra layers originate from a number of volcanoes in the region. This new tephrostratigraphy improves our knowledge of the important history of explosive volcanism in this area, potentially tying the tephrostratigraphies of surrounding areas (e.g., [4]) and allowing improved evaluation of regional volcanic risk. [1] Naranjo, J.A.., and C. R. Stern, 2004. Holocene tephrochronology of the southernmost part (42°30'-45°S) of the Andean Southern Volcanic Zone. Revista geológica de Chile, 31, pp. 225-240. [2] Heusser, C.J., et al., 1992. Paleoecology of late Quaterary deposits in Chiloé Continental, Chile. Revista Chilena de Historia Natural, 65, pp. 235-245. [3] Blockley, S.P.E., et al., 2005. A new and less destructive laboratory procedure for the physical separation of distal glass tephra shards from sediments. Quaternary Science Reviews, 24, pp. 1952-1960. [4] Watt, S.F.L., et al., 2011. Holocene tephrochronology of the Hualaihue region (Andean southern volcanic zone, ~42°S), southern Chile. Quaternary International, 246, pp. 324-343.

  11. Hydrothermal systems and volcano geochemistry

    Science.gov (United States)

    Fournier, R.O.

    2007-01-01

    The upward intrusion of magma from deeper to shallower levels beneath volcanoes obviously plays an important role in their surface deformation. This chapter will examine less obvious roles that hydrothermal processes might play in volcanic deformation. Emphasis will be placed on the effect that the transition from brittle to plastic behavior of rocks is likely to have on magma degassing and hydrothermal processes, and on the likely chemical variations in brine and gas compositions that occur as a result of movement of aqueous-rich fluids from plastic into brittle rock at different depths. To a great extent, the model of hydrothermal processes in sub-volcanic systems that is presented here is inferential, based in part on information obtained from deep drilling for geothermal resources, and in part on the study of ore deposits that are thought to have formed in volcanic and shallow plutonic environments.

  12. Pattern Matching for Volcano Status Assessment: what monitoring data alone can say about Mt. Etna activity

    Science.gov (United States)

    Cannavo, F.; Cannata, A.; Cassisi, C.

    2017-12-01

    The importance of assessing the ongoing status of active volcanoes is crucial not only for exposures to the local population but due to possible presence of tephra also for airline traffic. Adequately monitoring of active volcanoes, hence, plays a key role for civil protection purposes. In last decades, in order to properly monitor possible threats, continuous measuring networks have been designed and deployed on most of potentially hazardous volcanos. Nevertheless, at the present, volcano real-time surveillance is basically delegated to one or more human experts in volcanology, who interpret data coming from different kind of monitoring networks using their experience and non-measurable information (e.g. information from the field) to infer the volcano status. In some cases, raw data are used in some models to obtain more clues on the ongoing activity. In the last decades, with the development of volcano monitoring networks, huge amount of data of different geophysical, geochemical and volcanological types have been collected and stored in large databases. Having such big data sets with many examples of volcanic activity allows us to study volcano monitoring from a machine learning perspective. Thus, exploiting opportunities offered by the abundance of volcano monitoring time-series data we can try to address the following questions: Are the monitored parameters sufficient to discriminate the volcano status? Is it possible to infer/distinguish the volcano status only from the multivariate patterns of measurements? Are all the kind of measurements in the pattern equally useful for status assessment? How accurate would be an automatic system of status inference based only on pattern recognition of data? Here we present preliminary results of the data analysis we performed on a set of data and activity covering the period 2011-2017 at Mount Etna (Italy). In the considered period, we had 52 events of lava fountaining and long periods of Strombolian activity. We

  13. Communication Between Volcanoes: a Possible Path

    Science.gov (United States)

    Linde, A. T.; Sacks, I. S.

    2002-12-01

    The Japan Meteorological Agency installed and operates a network of Sacks-Evertson type borehole strainmeters in south-east Honshu. One of these instruments is on Izu-Oshima, a volcanic island at the northern end of the Izu-Bonin arc. That strainmeter recorded large strain changes associated with the 1986 eruption of Miharayama on the island and, over the period from 1980 to the 1986 eruption, the amplitude of the solid earth tides changed by almost a factor of two. Miyake-jima, about 75 km south of Izu-Oshima, erupted in October 1983. No deformation monitoring was available on Miyake but several changes occurred in the strain record at Izu-Oshima. There was a clear decrease in amplitude of the long-term strain rate. Short period (~hour) events recorded by the strainmeter became much more frequent about 6 months before the Miyake eruption and ceased following the eruption. At the time of the Miyake eruption, the rate of increase of the tidal amplitude also decreased. While all of these changes were observed on a single instrument, they are very different types of change. From a number of independent checks, we can be sure that the strainmeter did not experience any change in performance at that time. Thus it recorded a change in deformation behavior in three very different frequency bands: over very long term, at tidal periods (~day) and at very short periods (~hour). It appears that the distant eruption in 1983 had an effect on the magmatic system under Izu-Oshima. It is likely that these changes were enhanced to the observed level because Izu-Oshima was itself close to eruption failure. More recent tomographic and seismic attenuation work in the Tohoku (northern Honshu) area has shown the existence of a low velocity, high attenuation horizontally elongated structure under the volcanic front. This zone, likely to contain partial melt, is horizontally continuous along the front. If such a structure exists in the similar tectonic setting for these volcanoes, it

  14. Rising Expectations in Brazil and Chile

    Science.gov (United States)

    Elacqua, Gregory; Alves, Fatima

    2014-01-01

    Two themes connect Brazil and Chile: one is economic success; the other is social unrest. Protests rocked cities across Brazil in June 2013, and in Chile, recent student protests turned violent. Yet living conditions in both nations are better now than they've ever been. Successful economic and social reforms over the last two decades have led to…

  15. Remote Triggering of Microearthquakes in the Piton de la Fournaise and Changbaishan Volcanoes

    Science.gov (United States)

    Li, C.; Liu, G.; Peng, Z.; Brenguier, F.; Dufek, J.

    2015-12-01

    Large earthquakes are capable of triggering seismic, aseismic and hydrological responses at long-range distances. In particular, recent studies have shown that microearthquakes are mostly triggered in volcanic/geothermal regions. However, it is still not clear how widespread the phenomenon is, and whether there are any causal links between large earthquakes and subsequent volcanic unrest/eruptions. In this study we conduct a systematic search for remotely triggered activity at the Piton de la Fournaise (PdlF) and Changbaishan (CBS) volcanoes. The PdlF is a shield volcano located on the east-southern part of the Reunion Island in Indian Ocean. It is one of the most active volcanoes around the world. The CBS volcano is an intraplate stratovolcano on the border between China and North Korea, and it was active with a major eruption around 1100 years ago and has been since dormant from AD 1903, however, it showed signals of unrest recently. We choose these regions because they are well instrumented and spatially close to recent large earthquakes, such as the 2004/12/26 Mw9.1 Sumatra, 2011/03/11 Mw9.0 Tohoku, and the 2012/04/11 Mw8.6 Indian Ocean Earthquakes. By examining continuous waveforms a few hours before and after many earthquakes since 2000, we find many cases of remote triggering around the CBS volcano. In comparison, we only identify a few cases of remotely triggered seismicity around the PdlF volcano, including the 2004 Sumatra earthquake. Notably, the 2012 Indian Ocean earthquake and its M8.2 aftershock did not trigger any clear increase of seismicity, at least during their surface waves. Our next step is to apply a waveform matching method to automatically detect volcano-seismicity in both regions, and then use them to better understand potential interactions between large earthquakes and volcanic activities.

  16. Lahar hazards at Mombacho Volcano, Nicaragua

    Science.gov (United States)

    Vallance, J.W.; Schilling, S.P.; Devoli, G.

    2001-01-01

    Mombacho volcano, at 1,350 meters, is situated on the shores of Lake Nicaragua and about 12 kilometers south of Granada, a city of about 90,000 inhabitants. Many more people live a few kilometers southeast of Granada in 'las Isletas de Granada and the nearby 'Peninsula de Aseses. These areas are formed of deposits of a large debris avalanche (a fast moving avalanche of rock and debris) from Mombacho. Several smaller towns with population, in the range of 5,000 to 12,000 inhabitants are to the northwest and the southwest of Mombacho volcano. Though the volcano has apparently not been active in historical time, or about the last 500 years, it has the potential to produce landslides and debris flows (watery flows of mud, rock, and debris -- also known as lahars when they occur on a volcano) that could inundate these nearby populated areas. -- Vallance, et.al., 2001

  17. Analysis of volcano rocks by Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Sitek, J.; Dekan, J.

    2012-01-01

    In this work we have analysed the basalt rock from Mount Ba tur volcano situated on the Island of Bali in Indonesia.We compared our results with composition of basalt rocks from some other places on the Earth. (authors)

  18. Moessbauer Spectroscopy study of Quimsachata Volcano materials

    International Nuclear Information System (INIS)

    Dominguez, A.G.B.

    1988-01-01

    It has been studied volcanic lava from Quimsachata Volcano in Pem. Moessbauer Spectroscopy, X-ray diffraction, electronic and optical microscopy allowed the identification of different mineralogical phases. (A.C.AS.) [pt

  19. Lahar hazards at Agua volcano, Guatemala

    Science.gov (United States)

    Schilling, S.P.; Vallance, J.W.; Matías, O.; Howell, M.M.

    2001-01-01

    At 3760 m, Agua volcano towers more than 3500 m above the Pacific coastal plain to the south and 2000 m above the Guatemalan highlands to the north. The volcano is within 5 to 10 kilometers (km) of Antigua, Guatemala and several other large towns situated on its northern apron. These towns have a combined population of nearly 100,000. It is within about 20 km of Escuintla (population, ca. 100,000) to the south. Though the volcano has not been active in historical time, or about the last 500 years, it has the potential to produce debris flows (watery flows of mud, rock, and debris—also known as lahars when they occur on a volcano) that could inundate these nearby populated areas.

  20. [Antimicrobial susceptibility in Chile 2012].

    Science.gov (United States)

    Cifuentes-D, Marcela; Silva, Francisco; García, Patricia; Bello, Helia; Briceño, Isabel; Calvo-A, Mario; Labarca, Jaime

    2014-04-01

    Bacteria antimicrobial resistance is an uncontrolled public health problem that progressively increases its magnitude and complexity. The Grupo Colaborativo de Resistencia, formed by a join of experts that represent 39 Chilean health institutions has been concerned with bacteria antimicrobial susceptibility in our country since 2008. In this document we present in vitro bacterial susceptibility accumulated during year 2012 belonging to 28 national health institutions that represent about 36% of hospital discharges in Chile. We consider of major importance to report periodically bacteria susceptibility so to keep the medical community updated to achieve target the empirical antimicrobial therapies and the control measures and prevention of the dissemination of multiresistant strains.

  1. 2015 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory

    Science.gov (United States)

    Dixon, James P.; Cameron, Cheryl E.; Iezzi, Alexandra M.; Wallace, Kristi

    2017-09-28

    The Alaska Volcano Observatory (AVO) responded to eruptions, volcanic unrest or suspected unrest, and seismic events at 14 volcanic centers in Alaska during 2015. The most notable volcanic activity consisted of continuing intermittent ash eruptions from Cleveland and Shishaldin volcanoes in the Aleutian Islands. Two eruptive episodes, at Veniaminof and Pavlof, on the Alaska Peninsula ended in 2015. During 2015, AVO re-established the seismograph network at Aniakchak, installed six new broadband seismometers throughout the Aleutian Islands, and added a Multiple component Gas Analyzer System (MultiGAS) station on Augustine.

  2. Characterization of individual aerosol particles from the eruption of Lonquimay volcano in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Koltay, E. E-mail: koltay@atomki.hu; Rajta, I.; Morales, J.R.; Borbely-Kiss, I.; Kiss, A.Z

    1999-04-02

    A set of aerosol samples collected during major volcanic activities around the Chilean site Lonquimay in the years 1988-1990 has been subjected to measurements in conventional and microPIXE modes in the Debrecen institute. The aim of the study was the completion of the earlier results with comparative PIXE data and microPIXE measurements for the characterization of individual particles. Results have been obtained on separate particles in terms of their elemental composition, on separate particle groups of different composition by statistical dissimilarity analysis. Si/Al and K/Si elemental ratios have been used for a comparison with published data from other volcanic locations.

  3. Teenage sexuality and rights in Chile: from denial to punishment.

    Science.gov (United States)

    Casas, Lidia; Ahumada, Claudia

    2009-11-01

    While Chile sees itself as a country that has fully restored human rights since its return to democratic rule in 1990, the rights of teenagers to comprehensive sexuality education are still not being met. This paper reviews the recent history of sexuality education in Chile and related legislation, policies and programmes. It also reports a 2008 review of the bylaws of 189 randomly selected Chilean schools, which found that although such bylaws are mandatory, the absence of bylaws to prevent discrimination on grounds of pregnancy, HIV and sexuality was common. In relation to how sexual behaviour and discipline were addressed, bylaws that were non-compliant with the law were very common. Opposition to sexuality education in schools in Chile is predicated on the denial of teenage sexuality, and many schools punish sexual behaviour where transgression is perceived to have taken place. While the wider Chilean society has been moving towards greater recognition of individual autonomy and sexual diversity, this cultural shift has yet to be reflected in the government's political agenda, in spite of good intentions. Given this state of affairs, the Chilean polity needs to recognise its youth as having human rights, or will continue to fail in its commitment to them.

  4. Active volcanoes observed through Art: the contribution offered by the social networks

    Science.gov (United States)

    Neri, Marco; Neri, Emilia

    2015-04-01

    Volcanoes have always fascinated people for the wild beauty of their landscapes and also for the fear that they arouse with their eruptive actions, sometimes simply spectacular, but other times terrifying and catastrophic for human activities. In the past, volcanoes were sometimes imagined as a metaphysical gateway to the otherworld; they have inspired the creation of myths and legends ever since three thousand years ago, also represented by paintings of great artistic impact. Modern technology today offers very sophisticated and readily accessed digital tools, and volcanoes continue to be frequently photographed and highly appreciated natural phenomena. Moreover, in recent years, the spread of social networks (Facebook, Twitter, YouTube, Instagram, etc.) have made the widespread dissemination of graphic contributions even easier. The result is that very active and densely inhabited volcanoes such as Etna, Vesuvius and Aeolian Islands, in Italy, have become among the most photographed subjects in the world, providing a popular science tool with formidable influence and usefulness. The beauty of these landscapes have inspired both professional artists and photographers, as well as amateurs, who compete in the social networks for the publication of the most spectacular, artistic or simply most informative images. The end result of this often frantic popular scientific activity is at least two-fold: on one hand, it provides geoscientists and science communicators a quantity of documentation that is almost impossible to acquire through the normal systems of volcano monitoring, while on the other it raises awareness and respect for the land among the civil community.

  5. Volcano-ice interaction as a microbial habitat on Earth and Mars.

    Science.gov (United States)

    Cousins, Claire R; Crawford, Ian A

    2011-09-01

    Volcano-ice interaction has been a widespread geological process on Earth that continues to occur to the present day. The interaction between volcanic activity and ice can generate substantial quantities of liquid water, together with steep thermal and geochemical gradients typical of hydrothermal systems. Environments available for microbial colonization within glaciovolcanic systems are wide-ranging and include the basaltic lava edifice, subglacial caldera meltwater lakes, glacier caves, and subsurface hydrothermal systems. There is widespread evidence of putative volcano-ice interaction on Mars throughout its history and at a range of latitudes. Therefore, it is possible that life on Mars may have exploited these habitats, much in the same way as has been observed on Earth. The sedimentary and mineralogical deposits resulting from volcano-ice interaction have the potential to preserve evidence of any indigenous microbial populations. These include jökulhlaup (subglacial outflow) sedimentary deposits, hydrothermal mineral deposits, basaltic lava flows, and subglacial lacustrine deposits. Here, we briefly review the evidence for volcano-ice interactions on Mars and discuss the geomicrobiology of volcano-ice habitats on Earth. In addition, we explore the potential for the detection of these environments on Mars and any biosignatures these deposits may contain.

  6. Rapid mixing and short storage timescale in the magma dynamics of a steady-state volcano

    Science.gov (United States)

    Petrone, Chiara Maria; Braschi, Eleonora; Francalanci, Lorella; Casalini, Martina; Tommasini, Simone

    2018-06-01

    Steady-state volcanic activity implies equilibrium between the rate of magma replenishment and eruption of compositionally homogeneous magmas, lasting for tens to thousands of years in an open conduit system. The Present-day activity of Stromboli volcano (Aeolian Islands, Southern Italy) has long been recognised as typical of a steady-state volcano, with a shallow magmatic reservoir (highly porphyritic or hp-magma) continuously refilled by more mafic magma (with low phenocryst content or lp-magma) at a constant rate and accompanied by mixing, crystallisation and eruption. Our aim is to clarify the timescale and dynamics of the plumbing system at the establishment of the Present-day steady-state activity (volcanoes.

  7. President of Chile at CERN

    CERN Multimedia

    2007-01-01

    The President of Chile, Michelle Bachelet, in the ATLAS cavern with, from left to right, Peter Jenni, ATLAS Spokesman, Vivian Heyl, CONICYT President, and Robert Aymar, CERN Director-General. Robert Aymar, CERN Director-General, and Vivian Heyl, CONICYT President, signing a cooperation agreement between CERN and Chile’s Comisión Nacional de Investigación Científica y Tecnológica (CONICYT).The President of Chile, Michelle Bachelet, paid a visit to CERN during her three-day tour of Switzerland. The charismatic Michelle Bachelet and her large delegation were greeted by the CERN Director-General and then taken to see the ATLAS experiment and the LHC. She also took time to meet the Chilean community working at CERN, comprising several physicists in the Theory Group and the ATLAS experiment. The meeting was followed by the signing of a cooperation agreement between CERN and Chile’s Comisión Nacional de Investigación Científi...

  8. Tremor Source Location at Okmok Volcano

    Science.gov (United States)

    Reyes, C. G.; McNutt, S. R.

    2007-12-01

    Initial results using an amplitude-based tremor location program have located several active tremor episodes under Cone A, a vent within Okmok volcano's 10 km caldera. Okmok is an andesite volcano occupying the north-eastern half of Umnak Island, in the Aleutian islands. Okmok is defined by a ~2000 y.b.p. caldera that contains multiple cinder cones. Cone A, the youngest of these, extruded lava in 1997 covering the caldera floor. Since April 2003, continuous seismic data have been recorded from eight vertical short-period stations (L4-C's) installed at distances from Cone A ranging from 2 km to 31 km. In 2004 four additional 3- component broadband stations were added, co-located with continuous GPS stations. InSAR and GPS measurements of post-eruption deformation show that Okmok experienced several periods of rapid inflation (Mann and Freymueller, 2002), from the center of the 10 km diameter caldera. While there are few locatable VT earthquakes, there has been nearly continuous low-level tremor with stronger amplitude bursts occurring at variable rates and durations. The character of occurrence remained relatively constant over the course of days to weeks until the signal ceased in mid 2005. Within any day, tremor behavior remains fairly consistent, with bursts closely resembling each other, suggesting a single main process or source location. The tremor is composed of irregular waves with a broad range of frequencies, though most energy resides between ~2 Hz and 6 Hz. Attempts to locate the tremor using traditional arrival time methods fail because the signal is emergent, with envelopes too ragged to correlate on time scales that hold much hope for a location. Instead, focus was shifted to the amplitude ratios at various stations. Candidates for the tremor source include the center of inflation and Cone A, 3 km to the south-west. For all dates on record, data were band pass filtered between 1 and 5 Hz, then evaluated in 20.48 second windows (N=2048, sampling rate

  9. Space volcano observatory (SVO): a metric resolution system on-board a micro/mini-satellite

    Science.gov (United States)

    Briole, P.; Cerutti-Maori, G.; Kasser, M.

    2017-11-01

    1500 volcanoes on the Earth are potentially active, one third of them have been active during this century and about 70 are presently erupting. At the beginning of the third millenium, 10% of the world population will be living in areas directly threatened by volcanoes, without considering the effects of eruptions on climate or air-trafic for example. The understanding of volcanic eruptions, a major challenge in geoscience, demands continuous monitoring of active volcanoes. The only way to provide global, continuous, real time and all-weather information on volcanoes is to set up a Space Volcano Observatory closely connected to the ground observatories. Spaceborne observations are mandatory and implement the ground ones as well as airborne ones that can be implemented on a limited set of volcanoes. SVO goal is to monitor both the deformations and the changes in thermal radiance at optical wavelengths from high temperature surfaces of the active volcanic zones. For that, we propose to map at high resolution (1 to 1,5 m pixel size) the topography (stereoscopic observation) and the thermal anomalies (pixel-integrated temperatures above 450°C) of active volcanic areas in a size of 6 x 6 km to 12 x 12 km, large enough for monitoring most of the target features. A return time of 1 to 3 days will allow to get a monitoring useful for hazard mitigation. The paper will present the concept of the optical payload, compatible with a micro/mini satellite (mass in the range 100 - 400 kg), budget for the use of Proteus platform in the case of minisatellite approach will be given and also in the case of CNES microsat platform family. This kind of design could be used for other applications like high resolution imagery on a limited zone for military purpose, GIS, evolution cadaster…

  10. Letter from Chile: Re-establishing health care in Chile

    Science.gov (United States)

    Jiménez, Jorge

    1993-01-01

    Chile's long term social policy has produced very impressive outcomes in general health indicators, with a national health service established as early as 1952. During the years of the Pinochet dictatorship (1973-89) public health institutions were greatly affected, with sharp diminution in financing which affected investment and salaries. The democratic government initiated in 1990 faced a difficult situation, with underpaid staff and decrepit hospitals. The ministry took immediate action to improve salaries and start an ambitious health sector reform including investment in infrastructure, technology, and modern management. Decentralisation and autonomy, changes in payment for service mechanisms, and a public-private mix are the main objectives of this reform, keeping the public role as predominant in the proposed structure. This process has been affected by union unrest and public opinion dissatisfaction, which tend to present obstacles to progress in this complicated issue. Imagesp729-ap730-a

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

    Science.gov (United States)

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

    2014-12-01

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

  12. Understanding the monotonous life of open vent mafic volcanoes

    Science.gov (United States)

    Costa Rodriguez, F.; Ruth, D. C. S.; Bornas, M.; Rivera, D. J. V. I.

    2016-12-01

    Mafic open vent volcanoes display prominent degassing plumes during quiescence but also erupt frequently, every few months or years. Their small and mildly explosive eruptions (volatile contents indicate that the magma reservoir system extends at least to 5 km depth. Mg/Fe pyroxene zoning and diffusion modeling suggests that mafic magma intrusion in a shallow, crystal-rich and more evolved reservoir has occurred repeatedly. The time scale for this process is the same for all 9 events, starting about 2 years prior and continuing up to eruption. We estimate the relative proportions of injecting to resident magma that vary from about 0.2 to 0.7, probably reflecting the local crystal-melt interaction during intrusion. The near constant magma composition is probably the result of buffering of new incoming magma by a crystal-rich upper reservoir, and erupted magmas are physical mixtures. However, we do not find evidence of large-scale crystal recycling from one eruption to another, implying the resetting of the system after each event. The recurrent eruptions and intrusions could be driven by the near continuous degassing of the volcano that induces a mass imbalance which leads to magma movement from depth to the shallow system [e.g., 1]. [1] Girona et al. (2016). Science Reports doi:10.1038/srep18212

  13. Chile: los mapuches y el Bicentenario Chile: Mapuches e do Bicentenario Chile: Mapuche and the Bicentennial

    Directory of Open Access Journals (Sweden)

    José Bengoa

    2011-12-01

    Full Text Available El Bicentenario de la República de Chile se conmemoró en el mes de septiembre del año 2010. Además de marcar un importante hito histórico, coincidió con un cambio político en el Gobierno del país, el que pasó de la Concertación de Partidos por la Democracia a la Alianza de partidos formada por la derecha chilena. Se cumplieron por tanto 20 años desde que en el año 1990 cambiara el Gobierno militar presidido por el general Pinochet. Ese largo tiempo, dos décadas, coincide con un período de políticas que el Estado ha implementado hacia los Pueblos Indígenas. El Proyecto “Conmemoraciones y Memorias Subalternas” ha realizado durante el año 2010 un conjunto de investigaciones de terreno y documentales tendientes a comprender del modo más objetivo y científico lo ocurrido en el período y por tanto la situación actual de las sociedades mapuches en sus complejas relaciones con la chilena.O Bicentenario da República do Chile comemorou-se no mês de Setembro do ano 2010. Junto com transformar-se num marco histórico, coincidiu com uma mudança política no Governo do país, que passou da Concertação de Partidos pela Democracia (centro-esquerda à Aliança de partidos formada pela direita chilena. Cumpriram-se por tanto 20 anos desde que em 1990 mudasse o Governo militar presidido pelo general Pinochet. Esse longo tempo, duas décadas, coincide com um período de políticas que o Estado implementou para com os Povos Indígenas. O Projeto “Comemorações e Memórias Subalternas” realizou durante o ano 2010 um conjunto de pesquisas de campo e documentais tendentes a compreender do modo mais objetivo e científico o ocorrido no período e, por tanto, a situação atual das sociedades mapuches em suas complexas relações com a chilena.The conmeration of the 200 years of the Independence of Chile was in September 2010. This year was also the political change from the Concertación de Partidos por la Democracia to the right

  14. May 2011 eruption of Telica Volcano, Nicaragua: Multidisciplinary observations

    Science.gov (United States)

    Witter, M. R.; Geirsson, H.; La Femina, P. C.; Roman, D. C.; Rodgers, M.; Muñoz, A.; Morales, A.; Tenorio, V.; Chavarria, D.; Feineman, M. D.; Furman, T.; Longley, A.

    2011-12-01

    Telica volcano, an andesitic stratovolcano in north-western Nicaragua, erupted in May 2011. The eruption, produced ash but no lava and required the evacuation of over 500 people; no injuries were reported. We present the first detailed report of the eruption, using information from the TElica Seismic ANd Deformation (TESAND) network, that provides real-time data, along with visual observations, ash leachate analysis, and fumarole temperature measurements. Telica is located in the Maribios mountain range. It is one of the most active volcanoes in Nicaragua and has frequent small explosions and rare large (VEI 4) eruptions, with the most recent sizable eruptions (VEI 2) occurring in 1946 and 1999. The 2011 eruption is the most explosive since 1999. The eruption consisted of a series of ash explosions, with the first observations from May 8, 2011 when local residents reported ash fall NE of the active crater. Popping sounds could be heard coming from the crater on May 10. On May 13, the activity intensified and continued with some explosions every day for about 2 weeks. The well-defined plumes originated from the northern part of the crater. Ash fall was reported 4 km north of the active crater on May 14. The largest explosion at 2:54 pm (local time) on May 21 threw rocks from the crater and generated a column 2 km in height. Fresh ash samples were collected on May 16, 18, and 21 and preliminary inspection shows that the majority of the material is fragmented rock and crystalline material, i.e. not juvenile. Ash leachates (ash:water = 1:25) contain a few ppb As, Se, and Cd; tens of ppb Co and Ni; and up to a few hundred ppb Cu and Zn. Telica typically has hundreds of small seismic events every day, even when the volcano is not erupting. The TESAND network detected an increase in the rate and magnitude of seismic activity, with a maximum magnitude of 3.3. Elevated fumarole temperatures at locations near the active vent were also observed throughout the May 2011

  15. Geopolitics representation: Chile and Argentina in southern ice fields

    Directory of Open Access Journals (Sweden)

    Karen Isabel Manzano Itura

    2015-11-01

    Full Text Available Geopolitics, from concept named in 1917 by Rudolf Kjellén has been in continuous evolution until today. Since the incorporation of the representations, the first concept has been of vital importance in different territorial conflicts’ analysis. By means of a geopolitical analysis, the present article intends to understand the geopolitical representations in the area of southern ice fields, the last boundaries issue that still remains in abeyance between Chile and Argentina and how is that both countries have discussed the problem on a basis of representations, in which maps have been the image of each one facing the other, favoring in this way competition between states.

  16. Dendroecological analysis of a Fitzroya cupressoides and a Nothofagus nitida stand in the Cordillera Pelada, Chile

    Science.gov (United States)

    Margaret S. Devall; Bernard R. Parresol; Juan J. Armesto

    1998-01-01

    Lumbering of Fitzroya cupressoides in Chile began in 1599 and continued until 1976, when the species was declared a national monument and cutting of live trees was prohibited. Today, F. cupressoides is threatened; many of the remaining stands in the coastal range appear to be declining, with a predominance of standing dead stems and patchy, sparse regeneration. The...

  17. Mujeres inmigrantes peruanas en Chile

    Directory of Open Access Journals (Sweden)

    Carolina Stefoni

    2002-01-01

    Full Text Available Este artículo reflexiona en torno a la situación de la migración peruana en Chile, en particular sobre la situación de exclusión social y laboral que enfrentan las mujeres inmigrantes en Santiago. La migración peruana se caracteriza por ser eminentemente femenina y con una alta concentración laboral de este grupo en el trabajo doméstico. ¿Por qué se han vuelto las labores la fuente principal de trabajo para estas mujeres?, ¿basta con señalar que se debe a mano de obra más barata o existen otros argumentos de tipo cultural y social que explican por qué empleadores/as chilenos contratan y prefieren a mujeres peruanas?

  18. Intercultural bilingual education in Chile

    Directory of Open Access Journals (Sweden)

    Williams Ibarra Figueroa

    2016-08-01

    Full Text Available This article is based on analysis of the actions of public bodies and institutions that are being created in Chile to meet demand in Intercultural Bilingual Education (IBE. The aim is to analyze the practical training of students in initial teacher training in intercultural basic education at the Catholic University of Temuco. In addition, reveal the working methods of collaborative field between family-school- community partnership in key initial identification and subsequent components and devices in the proper relationship of individuals, in order to establish criteria by biopsychosocial processes from the identity the Other and You as host in the plural diversity of human beings, with aim is to recommend  a public policy with an emphasis on multicultural values of each community, enriching the human condition and biopolitics regarding the integration from the educational training and the role that fits the state.

  19. Chile: perspectives in school health.

    Science.gov (United States)

    Langdon, M C; Gazmuri, C; Venegas, L

    1990-09-01

    The leading health problems of children and adolescents in Chile is reviewed. The Chilean educational system and how the system addresses its principal health problems are described. A school health program is described as well as other educational programs designed and developed by nongovernmental institutions which have a smaller coverage. Current research studies regarding growth and development, child morbidity, nutritional level, and mental health studies are reviewed. In addition, principal challenges that include developing more efficient ways of referring children, enriching the curriculum and teacher training, assigning school hours for health teachers, and enlarging coverage of the health care evaluation programs are outlined. Of special importance is developing prevention programs for parents and children using school and community leaders to prevent health problems in areas such as human sexuality education, decision-making, social abilities, and alcohol and drug abuse. Main efforts should be directed toward low-income families and children to improve life conditions.

  20. Village microgrids: The Chile project

    Energy Technology Data Exchange (ETDEWEB)

    Baring-Gould, E.I.

    1997-12-01

    This paper describes a village application in Chile. The objective was to demonstrate the technical, economic and institutional viability of renewable energy for rural electrification, as well as to allow local partners to gain experience with hybrid/renewable technology, resource assessment, system siting and operation. A micro-grid system is viewed as a small village system, up to 1200 kWh/day load with a 50 kW peak load. It can consist of components of wind, photovoltaic, batteries, and conventional generators. It is usually associated with a single generator source, and uses batteries to cover light day time loads. This paper looks at the experiences learned from this project with regard to all of the facets of planning and installing this project.

  1. Volcanoes in the Classroom--an Explosive Learning Experience.

    Science.gov (United States)

    Thompson, Susan A.; Thompson, Keith S.

    1996-01-01

    Presents a unit on volcanoes for third- and fourth-grade students. Includes demonstrations; video presentations; building a volcano model; and inviting a scientist, preferably a vulcanologist, to share his or her expertise with students. (JRH)

  2. Volcanostratigraphic Approach for Evaluation of Geothermal Potential in Galunggung Volcano

    Science.gov (United States)

    Ramadhan, Q. S.; Sianipar, J. Y.; Pratopo, A. K.

    2016-09-01

    he geothermal systems in Indonesia are primarily associated with volcanoes. There are over 100 volcanoes located on Sumatra, Java, and in the eastern part of Indonesia. Volcanostratigraphy is one of the methods that is used in the early stage for the exploration of volcanic geothermal system to identify the characteristics of the volcano. The stratigraphy of Galunggung Volcano is identified based on 1:100.000 scale topographic map of Tasikmalaya sheet, 1:50.000 scale topographic map and also geological map. The schematic flowchart for evaluation of geothermal exploration is used to interpret and evaluate geothermal potential in volcanic regions. Volcanostratigraphy study has been done on Galunggung Volcano and Talaga Bodas Volcano, West Java, Indonesia. Based on the interpretation of topographic map and analysis of the dimension, rock composition, age and stress regime, we conclude that both Galunggung Volcano and Talaga Bodas Volcano have a geothermal resource potential that deserve further investigation.

  3. Glaciers of Avacha group of volcanoes in Neoholocene

    Directory of Open Access Journals (Sweden)

    T. M. Manevich

    2016-01-01

    Full Text Available The study of moraines at the Avacha volcano group revealed that glaciers changes at all volcanoes within the group happened almost synchronously. Glacial deposits could be grouped into three generations, corresponding to three periods of glacier fluctuations in Neoholocene. The largest glaciation within the group occurred ~2000 years ago. Fragments of moraine, corresponding to that period were found only in the moraine complex of the Ditmar Glacier which was 15% larger then today at that time. The most of moraines at the Avacha volcano group were formed during the Little Ice Age, which in the studied region continued up to the first decades of XX centuries. The maximal advance of glaciers probably happened in XVII century. The moraine corresponding to that period was found at the Kozelsky Glacier valley. At present time the total area of glaciers which moraines were described and dated approaches 21.46  km2. The area of reconstructed moraines corresponding to the Little Ice Age is estimated to be 2.79 km2, therefore at that period the total glaciation area reaches 24,25 км2 exceeding the present area by 13%. It could be claimed that in general during the time past the Little Ice Age the glaciation nature and glacier types did not change sufficiently. The rate of glacier degradation at various parts of the group is different and depends mainly on exposition. At the valleys of four glaciers we found moraines formed in the middle of XX century. They may appear in 1941–1952 when the unfavorable weather conditions leaded to stable negative anomalies in accumulation have happened.

  4. Geodetic Volcano Monitoring Research in Canary Islands: Recent Results

    Science.gov (United States)

    Fernandez, J.; Gonzalez, P. J.; Arjona, A.; Camacho, A. G.; Prieto, J. F.; Seco, A.; Tizzani, P.; Manzo, M. R.; Lanari, R.; Blanco, P.; Mallorqui, J. J.

    2009-05-01

    The Canarian Archipelago is an oceanic island volcanic chain with a long-standing history of volcanic activity (> 40 Ma). It is located off the NW coast of the African continent, lying over a transitional crust of the Atlantic African passive margin. At least 12 eruptions have been occurred on the islands of Lanzarote, Tenerife and La Palma in the last 500 years. Volcanism manifest predominantly as basaltic strombolian monogenetic activity (whole archipelago) and central felsic volcanism (active only in Tenerife Island). We concentrate our studies in the two most active islands, Tenerife and La Palma. In these islands, we tested different methodologies of geodetic monitoring systems. We use a combination of ground- and space-based techniques. At Tenerife Island, a differential interferometric study was performed to detect areas of deformation. DInSAR detected two clear areas of deformation, using this results a survey-based GPS network was designed and optimized to control those deformations and the rest of the island. Finally, using SBAS DInSAR results weak spatial long- wavelength subsidence signals has been detected. At La Palma, the first DInSAR analysis have not shown any clear deformation, so a first time series analysis was performed detecting a clear subsidence signal at Teneguia volcano, as for Tenerife a GPS network was designed and optimized taking into account stable and deforming areas. After several years of activities, geodetic results served to study ground deformations caused by a wide variety of sources, such as changes in groundwater levels, volcanic activity, volcano-tectonics, gravitational loading, etc. These results proof that a combination of ground-based and space-based techniques is suitable tool for geodetic volcano monitoring in Canary Islands. Finally, we would like to strength that those results could have serious implications on the continuous geodetic monitoring system design and implementation for the Canary Islands which is under

  5. Chile and Mercosur: One Strategic Perspective

    National Research Council Canada - National Science Library

    Oviedo, Humberto

    2000-01-01

    ... a big free trade area. Chile has been proactive to open its economy unilaterally and now is looking for creating the best conditions to participate in some important economic blocks, as a NAFTA, MERCOSUR, the Asian-Pacific...

  6. A decade towards better health in Chile.

    Science.gov (United States)

    Helmke, Irene

    2011-10-01

    In 1990, after 17 years of dictatorship, Chile started rebuilding its political system with a focus on improving social conditions and health. A recent study of the last 10 years shows some positive results. Irene Helmke reports.

  7. May 1960 Puerto Montt, Valdivia, Chile Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — On May 22, 1960, a Mw 9.5 earthquake, the largest earthquake ever instrumentally recorded, occurred in southern Chile. The series of earthquakes that followed...

  8. Surface Observations from Punta Arenas, Chile

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surface Observations from Punta Arenas, in extreme southern Chile. WMO station ID 85934. Period of record 1896-1954. The original forms were scanned at the Museo...

  9. Volcano Trial Case on GEP: Systematically processing EO data

    OpenAIRE

    Baumann, Andreas Bruno Graziano

    2017-01-01

    Volcanoes can be found all over the world; on land and below water surface. Even nowadays not all volcanoes are known. About 600 erupted in geologically recent times and about 50-70 volcanoes are currently active. Volcanoes can cause earthquakes; throw out blasts and tephras; release (toxic) gases; lava can flow relatively slow down the slopes; mass movements like debris avalanches, and landslides can cause tsunamis; and fast and hot pyroclastic surge, flows, and lahars can travel fast down ...

  10. Chile ushers in new hydro era

    International Nuclear Information System (INIS)

    Moxon, S.

    1997-01-01

    The planned construction of two hydroelectric power plants at Peuchen and Mampil, will help to meet Chile's growing electricity demand. Securing finance for the project has been straight forward thanks to the optimal hydrological conditions, rivers with a very strong flow providing a large head of water over short distance. Hydropower plays a central role in Chile's generating capacity providing 70% of total energy consumption. Thus, the future of these projects will be highly successful, it is argued. (UK)

  11. Volcano Geodesy: Recent developments and future challenges

    Science.gov (United States)

    Fernandez, Jose F.; Pepe, Antonio; Poland, Michael; Sigmundsson, Freysteinn

    2017-01-01

    Ascent of magma through Earth's crust is normally associated with, among other effects, ground deformation and gravity changes. Geodesy is thus a valuable tool for monitoring and hazards assessment during volcanic unrest, and it provides valuable data for exploring the geometry and volume of magma plumbing systems. Recent decades have seen an explosion in the quality and quantity of volcano geodetic data. New datasets (some made possible by regional and global scientific initiatives), as well as new analysis methods and modeling practices, have resulted in important changes to our understanding of the geodetic characteristics of active volcanism and magmatic processes, from the scale of individual eruptive vents to global compilations of volcano deformation. Here, we describe some of the recent developments in volcano geodesy, both in terms of data and interpretive tools, and discuss the role of international initiatives in meeting future challenges for the field.

  12. Soil radon response around an active volcano

    International Nuclear Information System (INIS)

    Segovia, N.; Valdes, C.; Pena, P.; Mena, M.; Tamez, E.

    2001-01-01

    Soil radon behavior related to the volcanic eruptive period 1997-1999 of Popocatepetl volcano has been studied as a function of the volcanic activity. Since the volcano is located 60 km from Mexico City, the risk associated with an explosive eruptive phase is high and an intense surveillance program has been implemented. Previous studies in this particular volcano showed soil radon pulses preceding the initial phase of the eruption. The radon survey was performed with LR-115 track detectors at a shallow depth and the effect of the soil moisture during the rainy season has been observed on the detectors response. In the present state of the volcanic activity the soil radon behavior has shown more stability than in previous eruptive stages

  13. Predicting the Timing and Location of the next Hawaiian Volcano

    Science.gov (United States)

    Russo, Joseph; Mattox, Stephen; Kildau, Nicole

    2010-01-01

    The wealth of geologic data on Hawaiian volcanoes makes them ideal for study by middle school students. In this paper the authors use existing data on the age and location of Hawaiian volcanoes to predict the location of the next Hawaiian volcano and when it will begin to grow on the floor of the Pacific Ocean. An inquiry-based lesson is also…

  14. How Do Volcanoes Affect Human Life? Integrated Unit.

    Science.gov (United States)

    Dayton, Rebecca; Edwards, Carrie; Sisler, Michelle

    This packet contains a unit on teaching about volcanoes. The following question is addressed: How do volcanoes affect human life? The unit covers approximately three weeks of instruction and strives to present volcanoes in an holistic form. The five subject areas of art, language arts, mathematics, science, and social studies are integrated into…

  15. Living with Volcanoes: Year Eleven Teaching Resource Unit.

    Science.gov (United States)

    Le Heron, Kiri; Andrews, Jill; Hooks, Stacey; Larnder, Michele; Le Heron, Richard

    2000-01-01

    Presents a unit on volcanoes and experiences with volcanoes that helps students develop geography skills. Focuses on four volcanoes: (1) Rangitoto Island; (2) Lake Pupuke; (3) Mount Smart; and (4) One Tree Hill. Includes an answer sheet and resources to use with the unit. (CMK)

  16. Volcanoes muon imaging using Cherenkov telescopes

    International Nuclear Information System (INIS)

    Catalano, O.; Del Santo, M.; Mineo, T.; Cusumano, G.; Maccarone, M.C.; Pareschi, G.

    2016-01-01

    A detailed understanding of a volcano inner structure is one of the key-points for the volcanic hazards evaluation. To this aim, in the last decade, geophysical radiography techniques using cosmic muon particles have been proposed. By measuring the differential attenuation of the muon flux as a function of the amount of rock crossed along different directions, it is possible to determine the density distribution of the interior of a volcano. Up to now, a number of experiments have been based on the detection of the muon tracks crossing hodoscopes, made up of scintillators or nuclear emulsion planes. Using telescopes based on the atmospheric Cherenkov imaging technique, we propose a new approach to study the interior of volcanoes detecting of the Cherenkov light produced by relativistic cosmic-ray muons that survive after crossing the volcano. The Cherenkov light produced along the muon path is imaged as a typical annular pattern containing all the essential information to reconstruct particle direction and energy. Our new approach offers the advantage of a negligible background and an improved spatial resolution. To test the feasibility of our new method, we have carried out simulations with a toy-model based on the geometrical parameters of ASTRI SST-2M, i.e. the imaging atmospheric Cherenkov telescope currently under installation onto the Etna volcano. Comparing the results of our simulations with previous experiments based on particle detectors, we gain at least a factor of 10 in sensitivity. The result of this study shows that we resolve an empty cylinder with a radius of about 100 m located inside a volcano in less than 4 days, which implies a limit on the magma velocity of 5 m/h.

  17. Volcanoes muon imaging using Cherenkov telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, O. [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Del Santo, M., E-mail: melania@ifc.inaf.it [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Mineo, T.; Cusumano, G.; Maccarone, M.C. [INAF, Istituto di Astrofisica Spaziale e Fisica cosmica di Palermo, via U. La Malfa 153, I-90146 Palermo (Italy); Pareschi, G. [INAF Osservatorio Astronomico di Brera, Via E. Bianchi 46, I-23807, Merate (Italy)

    2016-01-21

    A detailed understanding of a volcano inner structure is one of the key-points for the volcanic hazards evaluation. To this aim, in the last decade, geophysical radiography techniques using cosmic muon particles have been proposed. By measuring the differential attenuation of the muon flux as a function of the amount of rock crossed along different directions, it is possible to determine the density distribution of the interior of a volcano. Up to now, a number of experiments have been based on the detection of the muon tracks crossing hodoscopes, made up of scintillators or nuclear emulsion planes. Using telescopes based on the atmospheric Cherenkov imaging technique, we propose a new approach to study the interior of volcanoes detecting of the Cherenkov light produced by relativistic cosmic-ray muons that survive after crossing the volcano. The Cherenkov light produced along the muon path is imaged as a typical annular pattern containing all the essential information to reconstruct particle direction and energy. Our new approach offers the advantage of a negligible background and an improved spatial resolution. To test the feasibility of our new method, we have carried out simulations with a toy-model based on the geometrical parameters of ASTRI SST-2M, i.e. the imaging atmospheric Cherenkov telescope currently under installation onto the Etna volcano. Comparing the results of our simulations with previous experiments based on particle detectors, we gain at least a factor of 10 in sensitivity. The result of this study shows that we resolve an empty cylinder with a radius of about 100 m located inside a volcano in less than 4 days, which implies a limit on the magma velocity of 5 m/h.

  18. Intense magmatic degassing through the lake of Copahue volcano, 2013-2014

    Science.gov (United States)

    Tamburello, G.; Agusto, M.; Caselli, A.; Tassi, F.; Vaselli, O.; Calabrese, S.; Rouwet, D.; Capaccioni, B.; Di Napoli, R.; Cardellini, C.; Chiodini, G.; Bitetto, M.; Brusca, L.; Bellomo, S.; Aiuppa, A.

    2015-09-01

    Here we report on the first assessment of volatile fluxes from the hyperacid crater lake hosted within the summit crater of Copahue, a very active volcano on the Argentina-Chile border. Our observations were performed using a variety of in situ and remote sensing techniques during field campaigns in March 2013, when the crater hosted an active fumarole field, and in March 2014, when an acidic volcanic lake covered the fumarole field. In the latter campaign, we found that 566 to 1373 t d-1 of SO2 were being emitted from the lake in a plume that appeared largely invisible. This, combined with our derived bulk plume composition, was converted into flux of other volcanic species (H2O ~ 10989 t d-1, CO2 ~ 638 t d-1, HCl ~ 66 t d-1, H2 ~ 3.3 t d-1, and HBr ~ 0.05 t d-1). These levels of degassing, comparable to those seen at many open-vent degassing arc volcanoes, were surprisingly high for a volcano hosting a crater lake. Copahue's unusual degassing regime was also confirmed by the chemical composition of the plume that, although issuing from a hot (65°C) lake, preserves a close-to-magmatic signature. EQ3/6 models of gas-water-rock interaction in the lake were able to match observed compositions and demonstrated that magmatic gases emitted to the atmosphere were virtually unaffected by scrubbing of soluble (S and Cl) species. Finally, the derived large H2O flux (10,988 t d-1) suggested a mechanism in which magmatic gas stripping drove enhanced lake water evaporation, a process likely common to many degassing volcanic lakes worldwide.

  19. Diversidad de la familia Carabidae (Coleoptera en Chile Diversity of the family Carabidae (Coleoptera in Chile

    Directory of Open Access Journals (Sweden)

    SERGIO ROIG-JUÑENT

    2001-09-01

    Full Text Available Carabidae constituye dentro de los coléopteros chilenos, la cuarta familia en importancia por su cantidad de especies. El presente trabajo incluye una breve compilación acerca de la historia de la familia y de las primeras expediciones realizadas en Chile. También se realizan comparaciones de la diversidad de carábidos chilenos con respecto a otros países y el Neotrópico. Para Chile, se conocen 21 tribus, con 95 géneros y 365 especies, que representan el 38,8, 28,8 y 7,9 % de la fauna del Neotrópico, respectivamente. Chile posee un bajo número de tribus comparado con otros países, sin embargo, constituye un área importante por la presencia de seis tribus relictuales, principalmente pangeicas o gondwánicas. Chile posee 18 géneros endémicos (18,5 % de su fauna de Carabidae, 28 cuya distribución está restringida a Chile y Argentina y seis restringidos a Chile, Argentina y Uruguay. La cantidad de especies presentes en Chile es inferior a la que poseen otros países de América del Sur, pero la cantidad de especies endémicas es muy alta (204 y representa el 55,8 % de su fauna de carábidos. El alto grado de endemismo que posee Chile con respecto a otros países de América del Sur puede deberse a su condición de aislamiento, siendo las barreras más importantes la región desértica del norte y la cordillera de Los Andes. Este hecho también se vislumbra por la ausencia de importantes tribus neotropicales como Galeritini, Scaritini y Brachinini. También se incluyen en este trabajo claves para la identificación de todas las tribus y géneros presentes en Chile, como así también una breve descripción acerca de la diversidad y ambientes en los que se encuentra cada géneroThe family Carabidae is the fourth largest Coleoptera family in Chile. The present work includes a brief compilation on the taxonomic history of the family and the first expeditions to Chile. In addition, knowledge of carabid diversity in Chile is compared with

  20. The origin of the Hawaiian Volcano Observatory

    International Nuclear Information System (INIS)

    Dvorak, John

    2011-01-01

    I first stepped through the doorway of the Hawaiian Volcano Observatory in 1976, and I was impressed by what I saw: A dozen people working out of a stone-and-metal building perched at the edge of a high cliff with a spectacular view of a vast volcanic plain. Their primary purpose was to monitor the island's two active volcanoes, Kilauea and Mauna Loa. I joined them, working for six weeks as a volunteer and then, years later, as a staff scientist. That gave me several chances to ask how the observatory had started.

  1. Volcanology and volcano sedimentology of Sahand region

    International Nuclear Information System (INIS)

    Moine Vaziri, H.; Amine Sobhani, E.

    1977-01-01

    There was no volcano in Precambrian and Mesozoic eras in Iran, but in most place of Iran during the next eras volcanic rocks with green series and Dacites were seen. By the recent survey in Sahand mountain in NW of Iran volcanography, determination of rocks and the age of layers were estimated. The deposits of Precambrian as sediment rocks are also seen in the same area. All of volcanic periods in this place were studied; their extrusive rocks, their petrography and the result of their analytical chemistry were discussed. Finally volcano sedimentology of Sahand mountain were described

  2. The origin of the Hawaiian Volcano Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Dvorak, John [University of Hawaii' s Institute for Astronomy (United States)

    2011-05-15

    I first stepped through the doorway of the Hawaiian Volcano Observatory in 1976, and I was impressed by what I saw: A dozen people working out of a stone-and-metal building perched at the edge of a high cliff with a spectacular view of a vast volcanic plain. Their primary purpose was to monitor the island's two active volcanoes, Kilauea and Mauna Loa. I joined them, working for six weeks as a volunteer and then, years later, as a staff scientist. That gave me several chances to ask how the observatory had started.

  3. Nature's refineries — Metals and metalloids in arc volcanoes

    Science.gov (United States)

    Henley, R.W.; Berger, Byron R.

    2013-01-01

    Chemical data for fumaroles and for atmospheric gas and ash plumes from active arc volcanoes provide glimpses of the rates of release of metal and metalloids, such as Tl and Cd, from shallow and mid-crust magmas. Data from copper deposits formed in ancient volcanoes at depths of up to about 1500 m in the fractures below paleo-fumaroles, and at around 2000–4000 m in association with sub-volcanic intrusions (porphyry copper deposits) provide evidence of sub-surface deposition of Cu–Au–Ag–Mo and a range of other minor elements including Te, Se, As and Sb. These deposits, or ‘sinks’, of metals consistently record sustained histories of magmatic gas streaming through volcanic systems interspersed by continuing intrusive and eruptive activity. Here we integrate data from ancient and modern volcanic systems and show that the fluxes of metals and metalloids are controlled by a) the maintenance of fracture permeability in the stressed crust below volcanoes and b) the chemical processes that are triggered as magmatic gas, initially undersaturated with metals and metalloids, expands from lithostatic to very low pressure conditions through fracture arrays. The recognition of gas streaming may also account for the phenomenon of ‘excess degassing’, and defines an integral, but generally understated, component of active volcanic systems – a volcanic gas core – that is likely to be integral to the progression of eruptions to Plinean state.Destabilization of solvated molecular metal and metalloid species in magmatic gas mixtures and changes in their redox state are triggered, as it expands to the surface by abrupt pressure drops, or throttles' in the fracture array that guides expansion to the surface. The electronically harder, low electronegativity metals, such as copper and iron, deposit rapidly in response to expansion followed more slowly by arsenic with antimony as sulfosalts. Heavy, large radius, softer elements such as bismuth, lead, and thallium

  4. Constructing a reference tephrochronology for Augustine Volcano, Alaska

    Science.gov (United States)

    Wallace, Kristi; Coombs, Michelle L.

    2013-01-01

    -proximal sites, along with an off-island section 20 km to the west, provide the first continuous tephrochronology for Augustine that extends from the earliest to latest Holocene. Because examined pumice-fall exposures are limited to a narrow azimuth on the south side of the volcano, the on-island record is likely an incomplete catalog of major eruptions. It is possible however, that the coarse-grained near vent exposures (within 2 km) represent large eruptions that blanketed the entire island in tephra and are representative of the entire Holocene record. The major Holocene tephra units exposed on-island are composed of coarse-grained (cm-scale) pumice ranging in color from white to cream (variably oxidized), and light to medium gray as well as banded varieties. Accidental lithic assembles are highly variable and often unique for individual eruptions. Pumices range from 60-66 wt % SiO2 in whole-rock composition and are distinguishable using trace and minor element abundances and field context. Glass geochemistry is often distinguishable between tephras, but more overlap exists among deposits and presents challenges for correlating to regional tephras.

  5. Where Do Mexico and Chile Stand on Inclusive Education? Short Title: Inclusion in Mexico and Chile

    Science.gov (United States)

    García-Cedillo, Ismael; Romero-Contreras, Silvia; Ramos-Abadie, Liliana

    2015-01-01

    This paper discusses the background, current situation and challenges of educational integration and inclusive education in Mexico and Chile. These countries obtained similar low results on the academic achievement of their students (Mexico last and Chile second last) among OECD countries; and above average scores, among Latin-American countries.…

  6. Slope instability related to permafrost changes on Mexican volcanoes

    Science.gov (United States)

    Delgado Granados, Hugo; Molina, Victor Soto

    2015-04-01

    Permafrost is present above 4,500 meters at the three highest Mexican mountains, Citlaltépetl, Popocatépetl and Iztaccihuatl (5,675, 5,452 and 5,286m asl, respectively), all active volcanoes. During the rainy season in the central region of Mexico, the occurrence of small debris-flows in the ice-free parts of the mountains, as well as small lanslides is frequent. At Popocatépetl volcano, flows are mostly related to a combination of the eruptive activity and climatic factors. However, the volcanic activity is different at Citlaltépetl and Iztaccihuatl where there is no eruptive activity, but landslides have occurred in recent years on their steep slopes because its stability has been altered as a result of an increase in the air temperature which in turn has caused variations in the thickness of the active layer of permafrost, causing as a consequence, the increase of an even more unstable soil. Additionally, cracks in the rock walls are subject to an increasing hydrostatic pressure due to continuous daily freezing and thawing of seasonal water produced by a warmer and less solid precipitation accumulating in the cracks over time and in the unconsolidated potentially unstable material.

  7. Volcano monitoring using the Global Positioning System: Filtering strategies

    Science.gov (United States)

    Larson, K.M.; Cervelli, Peter; Lisowski, M.; Miklius, Asta; Segall, P.; Owen, S.

    2001-01-01

    Permanent Global Positioning System (GPS) networks are routinely used for producing improved orbits and monitoring secular tectonic deformation. For these applications, data are transferred to an analysis center each day and routinely processed in 24-hour segments. To use GPS for monitoring volcanic events, which may last only a few hours, real-time or near real-time data processing and subdaily position estimates are valuable. Strategies have been researched for obtaining station coordinates every 15 min using a Kalman filter; these strategies have been tested on data collected by a GPS network on Kilauea Volcano. Data from this network are tracked continuously, recorded every 30 s, and telemetered hourly to the Hawaiian Volcano Observatory. A white noise model is heavily impacted by data outages and poor satellite geometry, but a properly constrained random walk model fits the data well. Using a borehole tiltmeter at Kilauea's summit as ground-truth, solutions using different random walk constraints were compared. This study indicates that signals on the order of 5 mm/h are resolvable using a random walk standard deviation of 0.45 cm/???h. Values lower than this suppress small signals, and values greater than this have significantly higher noise at periods of 1-6 hours. Copyright 2001 by the American Geophysical Union.

  8. A Late Holocene explosive mafic eruption of Villarrica volcano, Southern Andes: The Chaimilla deposit

    Science.gov (United States)

    Costantini, L.; Pioli, L.; Bonadonna, C.; Clavero, J.; Longchamp, C.

    2011-03-01

    Villarrica (Chile) is one of the most active volcanoes in South America having erupted about 60 times in the last 460 years. Although its historical eruptive activity has been mainly effusive and weakly explosive, it had strong explosive behaviour in postglacial times. Chaimilla (activity. The deposit is dispersed over an area of 250 km 2 and consists of 8 units (A-H) which were grouped into four sequences. Stratigraphic data suggest that the eruption had a relatively short duration and evolved from i) an Opening phase, dispersing ash, lapilli clasts, accretionary lapilli, blocks and bombs, to ii) a Pulsatory phase, originating a series of magmatic explosions, to iii) a Collapsing phase, characterised by unstable plumes which emplaced a series of pyroclastic density currents intercalated with thin fallout layers and finally to iv) a Climactic phase forming a more sustained plume which eventually collapsed generating the final pyroclastic density currents. The deposit (fall and flow) has a minimum cumulative volume of 0.6 km 3, with the main sustained phase being associated with a VEI 4 and the flow units having a minimum estimated total volume of 0.04 km 3. The erupted material has a homogenous chemical composition but displays a remarkable variability in both textural and physical properties. The density distribution of juvenile products shows a clear bimodality characterised by two main populations: P1 and P2. Population P1 consists of highly vesicular clasts (modal density around 1000 kg m - 3 ) with mostly sub-spherical bubbles and moderately crystallised groundmass with large-sized microlites. Clasts from population P2 are poorly vesicular (modal density around 1600 kg m - 3 ) with irregular to collapsed bubbles and numerous smaller microlites. The variability of both vesicularity and microlite characteristics suggests the involvement of two magma batches with distinct pre-eruptive degassing and rising histories. Our eruption conceptual model implies the

  9. Automated tracking of lava lake level using thermal images at Kīlauea Volcano, Hawai’i

    Science.gov (United States)

    Patrick, Matthew R.; Swanson, Don; Orr, Tim R.

    2016-01-01

    Tracking the level of the lava lake in Halema‘uma‘u Crater, at the summit of Kīlauea Volcano, Hawai’i, is an essential part of monitoring the ongoing eruption and forecasting potentially hazardous changes in activity. We describe a simple automated image processing routine that analyzes continuously-acquired thermal images of the lava lake and measures lava level. The method uses three image segmentation approaches, based on edge detection, short-term change analysis, and composite temperature thresholding, to identify and track the lake margin in the images. These relative measurements from the images are periodically calibrated with laser rangefinder measurements to produce real-time estimates of lake elevation. Continuous, automated tracking of the lava level has been an important tool used by the U.S. Geological Survey’s Hawaiian Volcano Observatory since 2012 in real-time operational monitoring of the volcano and its hazard potential.

  10. Patterns of deformation and volcanic flows associated with lithospheric loading by large volcanoes on Venus

    Science.gov (United States)

    Mcgovern, Patrick J.; Solomon, Sean C.

    1993-01-01

    Magellan radar imaging and topography data are now available for a number of volcanoes on Venus greater than 100 km in radius. These data can be examined to reveal evidence of the flexural response of the lithosphere to the volcanic load. On Venus, erosion and sediment deposition are negligible, so tectonic evidence of deformation around large volcanoes should be evident except where buried by very young flows. Radar images reveal that most tectonic features and flow units on the flanks of these volcanoes have predominantly radial orientations. However, both Tepev Mons in Bell Regio and Sapas Mons in Atla Regio exhibit circumferential graben on their flanks. In addition, images reveal several flow units with an annular character around the north and west flanks of Tepev Mons. This pattern most likely results from ponding of flows in an annular flexural moat. Maat Mons in Atla Regio and Sif Mons in Eistla Regio are examples of volcanoes that lack circumferential graben and annular flows; discernible flow units and fractures on these constructs appear to be predominantly radial. Altimetry data can also provide evidence of flexural response. Tepev Mons is partially encircled by depressions that may be sections of a flexural moat that has not been completely filled. The locations of these depressions generally coincide with the annular flows described above. There is weaker evidence for such depressions around Maat Mons as well. The lack of circumferential tectonic features around most volcanoes on Venus might be explained by gradual moat filling and coverage by radial flows. The depressions around Tepev (and possible Maat) may indicate that this process is currently continuing. We use analytic models of plate flexure in an axisymmetric geometry to constrain the elastic plate thickness supporting Tepev Mons. If we consider the outer radius of the ponded flows to be the edge of a moat, we find that models with elastic plate thickness of 10-20 km fit best. Finite element

  11. Ecología trófica del jabalí europeo (Sus scrofa silvestre en Chile Trophic ecology of the wild boar (Sus scrofa in Chile

    Directory of Open Access Journals (Sweden)

    ÓSCAR SKEWES

    2007-09-01

    Full Text Available Documentamos la dieta del jabalí silvestre en el centro-sur de Chile basados en el examen de 20 estómagos colectados en los faldeos de volcán Mocho-Choshuenco (39°54' S, 72°02' O y en el Parque Nacional Vicente Pérez Rosales (41°03' S, 71°54' O. La dieta está representada por animales, vegetales y hongos. Entre los vegetales y hongos son consumidas tanto las partes epígeas como hipógeas, lo mismo que frutos y semillas. Hongos y rizomas de Gunnera tinctoria constituyen ítemes vegetales cuantitativamente importantes en la alimentación. El jabalí forrajea en general en ambiente boscoso, pero las especies vegetales más frecuentes en la dieta se encuentran en espacios abiertos o fuera del bosque. El ambiente dominado por Chusquea spp. constituye un importante sitio de alimentación. Los roedores de la familia Muridae dominan entre los animales determinados en la dieta del jabalí. Esta situación, sin embargo, parece obedecer a la ocurrencia de una ratada producto de la semillación masiva de Chusquea spp. durante la época de muestreo. Las aves de la familia Rhinocryptidae e invertebrados (en especial larvas del coleóptero Chiasognathus grantii constituyen parte frecuente de los ítemes animales de la dieta del jabalí. En comparación a estudios en otras partes del mundo, el jabalí silvestre en Chile consume hongos en porcentaje de ocurrencia similar (65 % a su dieta en Estados Unidos de América pero bastante más alta que su dieta en Europa (5-32 %. En relación al volumen del componente animal, el jabalí en Chile consume más (16,1 % que en Estados Unidos de América (6 % y que en Europa (7-13 %We document the diet of wild boar in south-central Chile based on analysis of 20 stomachs collected on the outskirts of Mocho-Choshuenco volcano (39°54' S, 72°02' W and of Vicente Pérez Rosales National Park (41°03' S, 71°54' W. The diet incorporates animals, plants and fungi. Among the latter two, both epigeal and hypogeal parts

  12. [Papillomavirus and cervical cancer in Chile].

    Science.gov (United States)

    O'Ryan, Miguel; Valenzuela, María Teresa

    2008-11-01

    Molecular, clinical and epidemiological studies have established beyond doubt that human papiloma viruses (HPV) cause cervical cancer. The virus is also associated with genital warts and other less common cancers in oropharynx, vulva, vagina and penis. Worldwide, VPH genotypes 16 and 18 are the most common high risk genotypes, detected in near 70% of women with cervical cancer. The discovery of a cause-effect relationship between several carcinogenic microorganisms and cancer open avenues for new diagnostic, treatment and prevention strategies. In this issue of Revista Médica de Chile, two papers on HPV are presented. Guzman and colleagues demonstrate that HPV can be detected in 66% to 77% of healthy male adolescents bypolymerase chain reaction and that positivity depends on the site of the penis that is sampled. These results support the role of male to female transmission of high risk HPVs in Chile and should lead to even more active educational campaigns. The second paper provides recommendations for HPV vaccine use in Chile, generated by the Immunization Advisory Committee of the Chilean Infectious Disease Society. To issue these recommendations, the Committee analyzes the epidemiological information available on HPV infection and cervical cancer in Chile, vaccine safety and effectiveness data, and describes cost-effectiveness studies. Taking into account that universal vaccination is controversial, the Committee favors vaccine use in Chile and it's incorporation into a national program. However, there is an indication that the country requires the implementation of an integrated surveillance approach including cross matching of data obtained from HPV genotype surveillance, monitoring of vaccination coverage, and surveillance of cervical cancer. The final decision of universal vaccine use in Chile should be based on a through analysis of information.ev Mid Chile

  13. Growth and degradation of Hawaiian volcanoes: Chapter 3 in Characteristics of Hawaiian volcanoes

    Science.gov (United States)

    Clague, David A.; Sherrod, David R.; Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.

    2014-01-01

    The 19 known shield volcanoes of the main Hawaiian Islands—15 now emergent, 3 submerged, and 1 newly born and still submarine—lie at the southeast end of a long-lived hot spot chain. As the Pacific Plate of the Earth’s lithosphere moves slowly northwestward over the Hawaiian hot spot, volcanoes are successively born above it, evolve as they drift away from it, and eventually die and subside beneath the ocean surface.

  14. Honey as a bioindicator of arsenic contamination due to volcanic and mining activities in Chile

    Directory of Open Access Journals (Sweden)

    José M Bastías

    2013-06-01

    Full Text Available The content of heavy metals in honey is indicative of natural or anthropogenic pollution and has therefore been proposed as a feasible bioindicator for arsenic contamination in different regions of Chile. Total arsenic (t-As and inorganic As (i-As concentrations were determined in 227 samples of honey harvested during the years 2007, 2008, and 2009 in the areas of San Pedro de Atacama, Atacama, Chiloé, and Futaleufú, with the last town located 156 km from the Chaitén Volcano (latest eruption in 2008. These analyses were conducted using an atomic absorption spectrophotometer coupled with a hydride generator. In the honey samples, the concentrations of t-As ranged from 2.2 to 171.9 μg kg-1, and the i-As concentrations ranged from none detected (ND to 24.6 μg kg-1, with the area of San Pedro de Atacama having the highest As concentrations. The samples of honey from Futaleufú showed higher As concentrations after the eruption of the Chaitén Volcano in 2008. This study demonstrates that As pollution in honey may originate from both natural and anthropogenic sources. The results indicate that it is appropriate to use honey as a bioindicator of environmental pollution. In addition, the consumption of the honey studied herein does not pose any health hazards to the consumer due to its As content.

  15. The Hawaiian Volcano Observatory: a natural laboratory for studying basaltic volcanism: Chapter 1 in Characteristics of Hawaiian volcanoes

    Science.gov (United States)

    Tilling, Robert I.; Kauahikaua, James P.; Brantley, Steven R.; Neal, Christina A.; Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.

    2014-01-01

    In the beginning of the 20th century, geologist Thomas A. Jaggar, Jr., argued that, to fully understand volcanic and associated hazards, the expeditionary mode of studying eruptions only after they occurred was inadequate. Instead, he fervently advocated the use of permanent observatories to record and measure volcanic phenomena—at and below the surface—before, during, and after eruptions to obtain the basic scientific information needed to protect people and property from volcanic hazards. With the crucial early help of American volcanologist Frank Alvord Perret and the Hawaiian business community, the Hawaiian Volcano Observatory (HVO) was established in 1912, and Jaggar’s vision became reality. From its inception, HVO’s mission has centered on several goals: (1) measuring and documenting the seismic, eruptive, and geodetic processes of active Hawaiian volcanoes (principally Kīlauea and Mauna Loa); (2) geological mapping and dating of deposits to reconstruct volcanic histories, understand island evolution, and determine eruptive frequencies and volcanic hazards; (3) systematically collecting eruptive products, including gases, for laboratory analysis; and (4) widely disseminating observatory-acquired data and analysis, reports, and hazard warnings to the global scientific community, emergency-management authorities, news media, and the public. The long-term focus on these goals by HVO scientists, in collaboration with investigators from many other organizations, continues to fulfill Jaggar’s career-long vision of reducing risks from volcanic and earthquake hazards across the globe.

  16. Regulated electricity retailing in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Galetovic, Alexander, E-mail: alexander@galetovic.cl [Facultad de Ciencias Economicas y Empresariales, Universidad de los Andes, Santiago, Chile. Av. San Carlos de Apoquindo 2200, Las Condes, Santiago (Chile); Munoz, Cristian M., E-mail: cmunozm@aes.com [AES Gener and Departamento de Ingenieria Electrica, Universidad Catolica de Chile (Chile)

    2011-10-15

    While some countries have unbundled distribution and retailing, skeptics argue that the physical attributes of electricity make retailers redundant. Instead, it is claimed that passive pass through of wholesale prices plus regulated charges for transmission and distribution suffice for customers to benefit from competitive generation markets. We review the Chilean experience with regulated retailing and pass through of wholesale prices. We argue that when energy wholesale prices are volatile and prices are stabilized, distortions emerge. Regulated retailers gain little by mitigating or correcting them. On the contrary, sometimes price distortions increase their profits. We estimate the cost of three distortions that neither regulated retailers nor the regulator have shown any interest in correcting. - Highlights: > We review Chile's experience with regulated electricity retailing. > Distortions emerge when energy wholesale prices are volatile and prices stabilized. > Regulated retailers gain little by mitigating or correcting distortions. > Sometimes price distortions increase retailers' profits. > We estimate the cost of three distortions, which retailers have not corrected.

  17. A unique collaboration in Chile.

    Science.gov (United States)

    1989-01-01

    The Chilean Red Cross Society and the family planning association--APROFA, International Planned Parenthood Federation's affiliate, are joining forces to help prevent the spread of the acquired immunodeficiency syndrome (AIDS) and human immunodeficiency virus (HIV) infection. APROFA established a working group to study the knowledge, attitudes, and sexual behavior of students at the National Training Institute, INACAP. 7000 students were sampled in 11 Chilean cities. The study found that 36% of the females, and 77% of males were sexually active before the age of 20. Nearly 1/2 of the women and 1/5 of the men did not know that condoms could protect them against sexually transmitted diseases (STDs) and pregnancy. APROFA designed a program to increase students knowledge of AIDS, reduce promiscuity and increase knowledge of and use of condoms. In October, 1988 an educational package distributed, consisting of a training manual, slides, educational booklets, a poster, and a video of 3 films. It has proved so successful that APROFA has adapted it for community groups, educational institutions, and its youth program. APROFA/Red Cross nurses and Red Cross volunteers have participated in workshops and training with the package. The Red Cross has organized AIDS-related activities in Chile since 1986, including education campaigns, information for blood donors, and a telephone hotline to provide AIDS counseling. Goals are to target more poor areas and groups outside of society's mainstream in the next year for sex education and information on STDs.

  18. Regulated electricity retailing in Chile

    International Nuclear Information System (INIS)

    Galetovic, Alexander; Munoz, Cristian M.

    2011-01-01

    While some countries have unbundled distribution and retailing, skeptics argue that the physical attributes of electricity make retailers redundant. Instead, it is claimed that passive pass through of wholesale prices plus regulated charges for transmission and distribution suffice for customers to benefit from competitive generation markets. We review the Chilean experience with regulated retailing and pass through of wholesale prices. We argue that when energy wholesale prices are volatile and prices are stabilized, distortions emerge. Regulated retailers gain little by mitigating or correcting them. On the contrary, sometimes price distortions increase their profits. We estimate the cost of three distortions that neither regulated retailers nor the regulator have shown any interest in correcting. - Highlights: → We review Chile's experience with regulated electricity retailing. → Distortions emerge when energy wholesale prices are volatile and prices stabilized. → Regulated retailers gain little by mitigating or correcting distortions. → Sometimes price distortions increase retailers' profits. → We estimate the cost of three distortions, which retailers have not corrected.

  19. Carbonate assimilation at Merapi volcano, Java Indonesia

    DEFF Research Database (Denmark)

    Chadwick, J.P; Troll, V.R; Ginibre,, C.

    2007-01-01

    Recent basaltic andesite lavas from Merapi volcano contain abundant, complexly zoned, plagioclase phenocrysts, analysed here for their petrographic textures, major element composition and Sr isotope composition. Anorthite (An) content in individual crystals can vary by as much as 55 mol% (An40^95...

  20. Probing magma reservoirs to improve volcano forecasts

    Science.gov (United States)

    Lowenstern, Jacob B.; Sisson, Thomas W.; Hurwitz, Shaul

    2017-01-01

    When it comes to forecasting eruptions, volcano observatories rely mostly on real-time signals from earthquakes, ground deformation, and gas discharge, combined with probabilistic assessments based on past behavior [Sparks and Cashman, 2017]. There is comparatively less reliance on geophysical and petrological understanding of subsurface magma reservoirs.

  1. Biological Studies on a Live Volcano.

    Science.gov (United States)

    Zipko, Stephen J.

    1992-01-01

    Describes scientific research on an Earthwatch expedition to study Arenal, one of the world's most active volcanoes, in north central Costa Rica. The purpose of the two-week project was to monitor and understand the past and ongoing development of a small, geologically young, highly active stratovolcano in a tropical, high-rainfall environment.…

  2. Of volcanoes, saints, trash, and frogs

    DEFF Research Database (Denmark)

    Andersen, Astrid Oberborbeck

    , at the same time as political elections and economic hardship. During one year of ethnographic fieldwork volcanoes, saints, trash and frogs were among the nonhuman entities referred to in conversations and engaged with when responding to the changes that trouble the world and everyday life of Arequipans...

  3. Geophysical monitoring of the Purace volcano, Colombia

    Directory of Open Access Journals (Sweden)

    M. Arcila

    1996-06-01

    Full Text Available Located in the extreme northwestern part of the Los Coconucos volcanic chain in the Central Cordillera, the Purace is one of Colombia's most active volcanoes. Recent geological studies indicate an eruptive history of mainly explosive behavior which was marked most recently by a minor ash eruption in 1977. Techniques used to forecast the renewal of activity of volcanoes after a long period of quiescence include the monitoring of seismicity and ground deformation near the volcano. As a first approach toward the monitoring of the Purace volcano, Southwest Seismological Observatory (OSSO, located in the city of Cali, set up one seismic station in 1986. Beginning in June 1991, the seismic signals have also been transmitted to the Colombian Geological Survey (INGEOMINAS at the Volcanological and Seismological Observatory (OVS-UOP, located in the city of Popayan. Two more seismic stations were installed early in 1994 forming a minimum seismic network and a geodetic monitoring program for ground deformation studies was established and conducted by INGEOMINAS.

  4. Muons reveal the interior of volcanoes

    CERN Multimedia

    Francesco Poppi

    2010-01-01

    The MU-RAY project has the very challenging aim of providing a “muon X-ray” of the Vesuvius volcano (Italy) using a detector that records the muons hitting it after traversing the rock structures of the volcano. This technique was used for the first time in 1971 by the Nobel Prize-winner Louis Alvarez, who was searching for unknown burial chambers in the Chephren pyramid.   The location of the muon detector on the slopes of the Vesuvius volcano. Like X-ray scans of the human body, muon radiography allows researchers to obtain an image of the internal structures of the upper levels of volcanoes. Although such an image cannot help to predict ‘when’ an eruption might occur, it can, if combined with other observations, help to foresee ‘how’ it could develop and serves as a powerful tool for the study of geological structures. Muons come from the interaction of cosmic rays with the Earth's atmosphere. They are able to traverse layers of ro...

  5. Relative Seismic Velocity Variations Correlate with Deformation at Kīlauea Volcano.

    Science.gov (United States)

    Donaldson, C.; Caudron, C.; Green, R. G.; White, R. S.

    2016-12-01

    Passive interferometry using ambient seismic noise is an appealing monitoring tool at volcanoes. The continuous nature of seismic noise provides better temporal resolution than earthquake interferometry and ambient noise may be sensitive to changes at depths that do not deform the volcano surface. Despite this, to our knowledge, no studies have yet comprehensively compared deformation and velocity at a volcano over a significant length of time. We use a volcanic tremor source (approximately 0.3 - 1.0 Hz) at Kīlauea volcano as a source for interferometry to measure relative velocity changes with time. The tremor source that dominates the cross correlations is located under the Halema'uma'u caldera at Kīlauea summit. By cross-correlating the vertical component of day-long seismic records between 200 pairs of stations, we extract coherent and temporally consistent coda wave signals with time lags of up to 70 seconds. Our resulting time series of relative velocity shows a remarkable correlation with the tilt record measured at Kīlauea summit. Kīlauea summit is continually inflating and deflating as the level of the lava lake rises and falls. During these deflation-inflation (DI) events the tilt increases (inflation), as the velocity increases, on the scale of days to weeks. In contrast, we also detect a longer-term velocity decrease between 2011-2015 as the volcano slowly inflates. We suggest that variations in velocity result from opening and closing cracks and pores due to changes in magma pressurization. Early modeling results indicate that pressurizing magma reservoirs at different depths can result in opposite changes in compression/extension at the surface. The consistent correlation of relative velocity and deformation in this study provides an opportunity to better understand the mechanism causing velocity changes, which currently limits the scope of passive interferometry as a monitoring tool.

  6. False Color Image of Volcano Sapas Mons

    Science.gov (United States)

    1991-01-01

    This false-color image shows the volcano Sapas Mons, which is located in the broad equatorial rise called Atla Regio (8 degrees north latitude and 188 degrees east longitude). The area shown is approximately 650 kilometers (404 miles) on a side. Sapas Mons measures about 400 kilometers (248 miles) across and 1.5 kilometers (0.9 mile) high. Its flanks show numerous overlapping lava flows. The dark flows on the lower right are thought to be smoother than the brighter ones near the central part of the volcano. Many of the flows appear to have been erupted along the flanks of the volcano rather than from the summit. This type of flank eruption is common on large volcanoes on Earth, such as the Hawaiian volcanoes. The summit area has two flat-topped mesas, whose smooth tops give a relatively dark appearance in the radar image. Also seen near the summit are groups of pits, some as large as one kilometer (0.6 mile) across. These are thought to have formed when underground chambers of magma were drained through other subsurface tubes and lead to a collapse at the surface. A 20 kilometer-diameter (12-mile diameter) impact crater northeast of the volcano is partially buried by the lava flows. Little was known about Atla Regio prior to Magellan. The new data, acquired in February 1991, show the region to be composed of at least five large volcanoes such as Sapas Mons, which are commonly linked by complex systems of fractures or rift zones. If comparable to similar features on Earth, Atla Regio probably formed when large volumes of molten rock upwelled from areas within the interior of Venus known as'hot spots.' Magellan is a NASA spacecraft mission to map the surface of Venus with imaging radar. The basic scientific instrument is a synthetic aperture radar, or SAR, which can look through the thick clouds perpetually shielding the surface of Venus. Magellan is in orbit around Venus which completes one turn around its axis in 243 Earth days. That period of time, one Venus day

  7. Hazard maps of Colima volcano, Mexico

    Science.gov (United States)

    Suarez-Plascencia, C.; Nunez-Cornu, F. J.; Escudero Ayala, C. R.

    2011-12-01

    Colima volcano, also known as Volcan de Fuego (19° 30.696 N, 103° 37.026 W), is located on the border between the states of Jalisco and Colima and is the most active volcano in Mexico. Began its current eruptive process in February 1991, in February 10, 1999 the biggest explosion since 1913 occurred at the summit dome. The activity during the 2001-2005 period was the most intense, but did not exceed VEI 3. The activity resulted in the formation of domes and their destruction after explosive events. The explosions originated eruptive columns, reaching attitudes between 4,500 and 9,000 m.a.s.l., further pyroclastic flows reaching distances up to 3.5 km from the crater. During the explosive events ash emissions were generated in all directions reaching distances up to 100 km, slightly affected nearby villages as Tuxpan, Tonila, Zapotlán, Cuauhtemoc, Comala, Zapotitlan de Vadillo and Toliman. During the 2005 this volcano has had an intense effusive-explosive activity, similar to the one that took place during the period of 1890 through 1900. Intense pre-plinian eruption in January 20, 1913, generated little economic losses in the lower parts of the volcano due to low population density and low socio-economic activities at the time. Shows the updating of the volcanic hazard maps published in 2001, where we identify whit SPOT satellite imagery and Google Earth, change in the land use on the slope of volcano, the expansion of the agricultural frontier on the east and southeast sides of the Colima volcano, the population inhabiting the area is approximately 517,000 people, and growing at an annual rate of 4.77%, also the region that has shown an increased in the vulnerability for the development of economic activities, supported by the construction of highways, natural gas pipelines and electrical infrastructure that connect to the Port of Manzanillo to Guadalajara city. The update the hazard maps are: a) Exclusion areas and moderate hazard for explosive events

  8. All projects related to chile | IDRC - International Development ...

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

    Strengthen the use of scientific evidence to inform climate policy, negotiations ... Evaluating the impact of digital tools to teach math and science in Chile ... Business Cooperation and Regional Productive Development in Chile, El Salvador, ...

  9. Geochemical studies on island arc volcanoes

    International Nuclear Information System (INIS)

    Notsu, Kenji

    1998-01-01

    This paper summarizes advances in three topics of geochemical studies on island arc volcanoes, which I and my colleagues have been investigating. First one is strontium isotope studies of arc volcanic rocks mainly from Japanese island arcs. We have shown that the precise spatial distribution of the 87 Sr/ 86 Sr ratio reflects natures of the subduction structure and slab-mantle interaction. Based on the 87 Sr/ 86 Sr ratio of volcanic rocks in the northern Kanto district, where two plates subduct concurrently with different directions, the existence of an aseismic portion of the Philippine Sea plate ahead of the seismic one was suggested. Second one is geochemical monitoring of active arc volcanoes. 3 He/ 4 He ratio of volcanic volatiles was shown to be a good indicator to monitor the behavior of magma: ascent and drain-back of magma result in increase and decrease in the ratio, respectively. In the case of 1986 eruptions of Izu-Oshima volcano, the ratio began to increase two months after big eruptions, reaching the maximum and decreased. Such delayed response is explained in terms of travelling time of magmatic helium from the vent area to the observation site along the underground steam flow. Third one is remote observation of volcanic gas chemistry of arc volcanoes, using an infrared absorption spectroscopy. During Unzen eruptions starting in 1990, absorption features of SO 2 and HCl of volcanic gas were detected from the observation station at 1.3 km distance. This was the first ground-based remote detection of HCl in volcanic gas. In the recent work at Aso volcano, we could identify 5 species (CO, COS, CO 2 , SO 2 and HCl) simultaneously in the volcanic plume spectra. (author)

  10. [The Revista Médica the Chile and medical education].

    Science.gov (United States)

    Goic, Alejandro

    2002-07-01

    With this issue, Revista Médica de Chile will have been published uninterruptedly, for 130 years. Formal medical education had an early development since Chile became independent from Spain (1817). The first Medical Sciences Course was organized in 1833 by the Irish physician William C Blest. The Santiago Medical Society was founded in 1869 and its journal-Revista Médica de Chile--in 1872. Its first director was Dr. German Schneider. Revista Medica is the oldest serial publication in South America and the second oldest in the Spanish speaking world. This is a remarkable fact for a comparatively young country. With the creation of the Medical Society and Revista Medica, a process of continuous medical education was started and they became a real Graduate School. The Journal has adopted the main changes in knowledge and technology. Some important milestones of its development, during the second half of the 20th century, were the definition of its objectives and structure, the incorporation of peer review of manuscripts (even with foreign reviewers) the adoption of international guidelines for publication, its incorporation into the main biomedical journal indexes, the modernization of its printing process, the making of a computer generated index of all papers published since 1872, its incorporation into a digital library in INTERNET and the active participation of its editors in the World Association of Medical Journal Editors. The success of the journal is influenced by the independence that the Medical Society has conferred to the editors (all outstanding University Professors), as well as to the characteristics of an educational campus "invisible and without tumult" (Ingelfinger).

  11. Radioactive wastes management development in Chile

    International Nuclear Information System (INIS)

    Mir, S.A.; Cruz, P.F.; Rivera, J.D.; Jorquera, O.H.

    1994-01-01

    A Facility for immobilizing and conditioning of radioactive wastes generated in Chile, has recently started in operation. It is a Radioactive Wastes Treatment Plant, RWTP, whose owner is Comision Chilena de Energia Nuclear, CCHEN. A Storgement Building of Conditioned Wastes accomplishes the facility for medium and low level activity wastes. The Project has been carried with participation of chilean professionals at CCHEN and Technical Assistance of International Atomic Energy Agency, IAEA. Processes developed are volume reduction by compaction; immobilization by cementation and conditioning. Equipment has been selected to process radioactive wastes into a 200 liters drum, in which wastes are definitively conditioned, avoiding exposition and contamination risks. The Plant has capacity to treat low and medium activity radioactive wastes produced in Chile due to Reactor Experimental No. 1 operation, and annex Laboratories in Nuclear Research Centers, as also those produced by users of nuclear techniques in Industries, Hospitals, Research Centers and Universities, in the whole country. With the infrastructure developed in Chile, a centralization of Radioactive Wastes Management activities is achieved. A data base system helps to control and register radioactive wastes arising in Chile. Generation of radioactive wastes in Chile, has found solution for the present production and that of near future

  12. Micro-earthquake signal analysis and hypocenter determination around Lokon volcano complex

    Energy Technology Data Exchange (ETDEWEB)

    Firmansyah, Rizky, E-mail: rizkyfirmansyah@hotmail.com [Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, 40132 (Indonesia); Nugraha, Andri Dian, E-mail: nugraha@gf.itb.ac.id [Global Geophysical Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, 40132 (Indonesia); Kristianto, E-mail: kris@vsi.esdm.go.id [Center for Volcanology and Geological Hazard Mitigation (CVGHM), Geological Agency, Bandung, 40122 (Indonesia)

    2015-04-24

    Mount Lokon is one of five active volcanoes which is located in the North Sulawesi region. Since June 26{sup th}, 2011, standby alert set by the Center for Volcanology and Geological Hazard Mitigation (CVGHM) for this mountain. The Mount Lokon volcano erupted on July 4{sup th}, 2011 and still continuously erupted until August 28{sup th}, 2011. Due to its high seismic activity, this study is focused to analysis of micro-earthquake signal and determine the micro-earthquake hypocenter location around the complex area of Lokon-Empung Volcano before eruption phase in 2011 (time periods of January, 2009 up to March, 2010). Determination of the hypocenter location was conducted with Geiger Adaptive Damping (GAD) method. We used initial model from previous study in Volcan de Colima, Mexico. The reason behind the model selection was based on the same characteristics that shared between Mount Lokon and Colima including andesitic stratovolcano and small-plinian explosions volcanian types. In this study, a picking events was limited to the volcano-tectonics of A and B types, hybrid, long-period that has a clear signal onset, and local tectonic with different maximum S – P time are not more than three seconds. As a result, we observed the micro-earthquakes occurred in the area north-west of Mount Lokon region.

  13. Frictional-faulting model for harmonic tremor before Redoubt Volcano eruptions

    Science.gov (United States)

    Dmitrieva, Ksenia; Hotovec-Ellis, Alicia J.; Prejean, Stephanie G.; Dunham, Eric M.

    2013-01-01

    Seismic unrest, indicative of subsurface magma transport and pressure changes within fluid-filled cracks and conduits, often precedes volcanic eruptions. An intriguing form of volcano seismicity is harmonic tremor, that is, sustained vibrations in the range of 0.5–5 Hz. Many source processes can generate harmonic tremor. Harmonic tremor in the 2009 eruption of Redoubt Volcano, Alaska, has been linked to repeating earthquakes of magnitudes around 0.5–1.5 that occur a few kilometres beneath the vent. Before many explosions in that eruption, these small earthquakes occurred in such rapid succession—up to 30 events per second—that distinct seismic wave arrivals blurred into continuous, high-frequency tremor. Tremor abruptly ceased about 30 s before the explosions. Here we introduce a frictional-faulting model to evaluate the credibility and implications of this tremor mechanism. We find that the fault stressing rates rise to values ten orders of magnitude higher than in typical tectonic settings. At that point, inertial effects stabilize fault sliding and the earthquakes cease. Our model of the Redoubt Volcano observations implies that the onset of volcanic explosions is preceded by active deformation and extreme stressing within a localized region of the volcano conduit, at a depth of several kilometres.

  14. Micro-earthquake signal analysis and hypocenter determination around Lokon volcano complex

    International Nuclear Information System (INIS)

    Firmansyah, Rizky; Nugraha, Andri Dian; Kristianto

    2015-01-01

    Mount Lokon is one of five active volcanoes which is located in the North Sulawesi region. Since June 26 th , 2011, standby alert set by the Center for Volcanology and Geological Hazard Mitigation (CVGHM) for this mountain. The Mount Lokon volcano erupted on July 4 th , 2011 and still continuously erupted until August 28 th , 2011. Due to its high seismic activity, this study is focused to analysis of micro-earthquake signal and determine the micro-earthquake hypocenter location around the complex area of Lokon-Empung Volcano before eruption phase in 2011 (time periods of January, 2009 up to March, 2010). Determination of the hypocenter location was conducted with Geiger Adaptive Damping (GAD) method. We used initial model from previous study in Volcan de Colima, Mexico. The reason behind the model selection was based on the same characteristics that shared between Mount Lokon and Colima including andesitic stratovolcano and small-plinian explosions volcanian types. In this study, a picking events was limited to the volcano-tectonics of A and B types, hybrid, long-period that has a clear signal onset, and local tectonic with different maximum S – P time are not more than three seconds. As a result, we observed the micro-earthquakes occurred in the area north-west of Mount Lokon region

  15. Zahraničně obchodní politika Chile

    OpenAIRE

    Horáková, Anna

    2009-01-01

    The Diploma thesis focuses on foreign trade policy of Chile. The first part is a brief summary of socio-economic characteristics of the country. The following section deals with the individual strategies in the approach to foreign trade policy applied in Chile since independence to the present. It exams the determinants of changes in foreign trade policy of Chile and monitors changes in territorial and commodity structure of the foreign trade of Chile. In the final section assesses the curren...

  16. [Beginning of the Microbiology education in Chile: formation centers].

    Science.gov (United States)

    Osorio, Carlos

    2015-08-01

    The first Chair of Microbiology in Chile was created in the School of Medicine of the Cañadilla at the University of Chile in 1892. Dr. Alejandro del Río Soto Aguilar was its first Professor. For almost three decades it was the only educational center for microbiologists in Chile. Among them were the first Professors of the new School of Medicine of the Catholic University of Chile and of the University of Concepción.

  17. Retail Bank Interest Rate Pass-Through; Is Chile Atypical?

    OpenAIRE

    Alessandro Rebucci; Marco A Espinosa-Vega

    2003-01-01

    This paper investigates empirically the pass-through of money market interest rates to retail banking interest rates in Chile, the United States, Canada, Australia, New Zealand, and five European countries. Overall, Chile's pass-through does not appear atypical. Based on a standard error-correction model, we find that, as in most countries considered, Chile's measured pass-through is incomplete. But Chile's pass-through is also faster than in many other countries considered and is comparable ...

  18. The Agency's Technical Co-operation programme in Chile, 1981-1991. Country programme evaluation

    International Nuclear Information System (INIS)

    1992-01-01

    Agency support for nuclear activities in Chile dates back to the early 1960s. During the last ten years, the period covered by this evaluation, this support has considerably expanded. In the period 1981-1991, 62 Agency projects with allotments amounting to over $7 million were completed or are under implementation. Through this co-operation Chile has received 360 man-months of expert services, $3.4 million worth of equipment, and 105 fellowships for some 390 man-months of training. In addition, 262 Chileans attended 219 Agency regional and interregional training courses, and Chilean institutions were awarded 40 research contracts worth over $325,000. This evaluation covers ten years of Agency technical co-operation with Chile, during which 35 projects were completed and 27 are still being implemented. Eight major sectors received assistance: general atomic energy development; nuclear physics; nuclear raw materials; nuclear engineering and technology; nuclear techniques in agriculture; nuclear medicine; hydrology; and nuclear safety. The evaluation concluded that, overall, the Agency's technical co-operation activities have, in keeping with the national priorities concerning peaceful nuclear applications, contributed substantially to the establishment of Chile's nuclear scientific and technical infrastructure, and played a major role in Chile's efforts to introduce nuclear applications in a number of sectors of the economy, with many benefits for broader national development objectives. Another strength of the Agency's programme with Chile is the high level of commitment and dedication that was noted in the great majority of recipient institutions, and in particular at the Comision Chilena de Energia Nuclear, CChEN. Mention should also be made of the fact that bureaucracy appears to be less severe than in some other developing countries, and that constraints that frequently affect other countries, such as insufficient counterpart commitment and lack of continuity of

  19. Expanding Geophysical and Geochemical Investigation of Causes of Extraordinary Unrest at the Laguna del Maule (Rhyolitic) Volcanic Field, Southern Andes, Chile

    Science.gov (United States)

    Singer, B. S.

    2014-12-01

    The Laguna del Maule Volcanic Field, Chile, includes an unusually large and recent concentration of silicic eruptions. Since 2007 the crust here has been inflating at an astonishing rate of 25 cm/yr. Findings thus far lead to the hypothesis that the silicic vents have tapped an extensive layer of crystal-poor, rhyolitic melt that began to form atop a magmatic mush zone that was established by ~20 ka with a renewed phase of rhyolite eruptions during the Holocene. Modeling of surface deformation, magnetotelluric data, and gravity changes suggest that magma is currently intruding at a depth of ~5 km. Swarms of volcano-tectonic and long period earthquakes, mostly of M San Juan-Argentina, Nanyang Technological University-Singapore, SERNAGEOMIN, OVDAS, USGS, and SEGEMAR-Argentina. Team members will be introduced in this presentation. Our approach includes augmenting the OVDAS array of 6 permanent seisic stations with 40 additional instruments to conduct tomographic, receiver function and ambient noise studies. We continue to collect 4-D gravity data from 37 stations. Surface deformation is monitored via cGPS at 5 permanent receivers and InSAR data. A magnetotelluric survey across the Andes at 36o S is planned. Geochemical studies include mineral zoning and U-Th disequilibrium of zircons to constrain the timing of magma intrusion and mixing events prior to the current unrest. The overall aim is to integrate these observations and to construct numerical models of system dynamics. We are developing communications protocols and a web site to facilitate sharing of findings among the team members and with the public.

  20. Radon soil increases before volcano-tectonic earthquakes in Colombia

    International Nuclear Information System (INIS)

    Garzon, G.; Serna, D.; Diago, J.; Moran, C.

    2003-01-01

    Continuous studies of radon concentration changes in soils for the purpose of earthquake monitoring have been carried out in three colombian districts and in the edifices of Galeras and nevado del Ruiz volcanoes since 1995. In zones of active faulting have been measured radon soil emissions between 1000 and 2500 pCi/L. In an intersection of two active geological faults have been measured levels of 25 000 pCi/L. In the present work appears a compilation of examples of the registered anomalous radon emissions in several stations before earthquakes of tectonic character. Examples of registered radon increases before: (1) events of magnitudes between 2 and 4; (2) the occurrence of seismic swarms; and (3) the Quindio (Colombia) earthquake (M w = 6, 2) of January 1999, are described. A model of transport mechanism for the studied isotopes is presented. (orig.)

  1. Expedition Atacama - project AMOS in Chile

    Science.gov (United States)

    Tóth, J.; Kaniansky, S.

    2016-01-01

    The Slovak Video Meteor Network operates since 2009 (Tóth et al., 2011). It currently consists of four semi-automated all-sky video cameras, developed at the Astronomical Observatory in Modra, Comenius University in Bratislava, Slovakia. Two new generations of AMOS (All-sky Meteor Orbit System) cameras operate fully automatically at the Canary Islands, Tenerife and La Palma, since March 2015 (Tóth et al., 2015). As a logical step, we plan to cover the southern hemisphere from Chile. We present observational experiences in meteor astronomy from the Atacama Desert and other astronomical sites in Chile. This summary of the observations lists meteor spectra records (26) between Nov.5-13, 2015 mostly Taurid meteors, single and double station meteors as well as the first light from the permanent AMOS stations in Chile.

  2. Space Radar Image of Colombian Volcano

    Science.gov (United States)

    1999-01-01

    This is a radar image of a little known volcano in northern Colombia. The image was acquired on orbit 80 of space shuttle Endeavour on April 14, 1994, by the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR). The volcano near the center of the image is located at 5.6 degrees north latitude, 75.0 degrees west longitude, about 100 kilometers (65 miles) southeast of Medellin, Colombia. The conspicuous dark spot is a lake at the bottom of an approximately 3-kilometer-wide (1.9-mile) volcanic collapse depression or caldera. A cone-shaped peak on the bottom left (northeast rim) of the caldera appears to have been the source for a flow of material into the caldera. This is the northern-most known volcano in South America and because of its youthful appearance, should be considered dormant rather than extinct. The volcano's existence confirms a fracture zone proposed in 1985 as the northern boundary of volcanism in the Andes. The SIR-C/X-SAR image reveals another, older caldera further south in Colombia, along another proposed fracture zone. Although relatively conspicuous, these volcanoes have escaped widespread recognition because of frequent cloud cover that hinders remote sensing imaging in visible wavelengths. Four separate volcanoes in the Northern Andes nations ofColombia and Ecuador have been active during the last 10 years, killing more than 25,000 people, including scientists who were monitoring the volcanic activity. Detection and monitoring of volcanoes from space provides a safe way to investigate volcanism. The recognition of previously unknown volcanoes is important for hazard evaluations because a number of major eruptions this century have occurred at mountains that were not previously recognized as volcanoes. Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves allowing detailed observations at any time, regardless of

  3. Socioeconomic determinants of disability in Chile.

    Science.gov (United States)

    Zitko Melo, Pedro; Cabieses Valdes, Báltica

    2011-10-01

    Disability is a worldwide public health priority. A shift from a biomedical perspective of dysfunction to a broader social understanding of disability has been proposed. Among many different social factors described in the past, socioeconomic position remains as a key multidimensional determinant of health. The study goal was to analyze the relationship between disability and different domains of socioeconomic position in Chile. Cross-sectional analysis of an anonymized population-based survey conducted in Chile in 2006. Any disability (dichotomous variable) and 6 different types of disability were analyzed on the bases of their relationship with income quintiles, occupational status, educational level, and material living standards (quality of the housing, overcrowding rate and sanitary conditions). Confounding and interaction effects were explored using R statistical program. Income, education, occupation, and material measures of socioeconomic position, along with some sociodemographic characteristics of the population, were independently associated with the chance of being disabled in Chile. Interestingly, classic measures of socioeconomic position (income, education, and occupation) were consistently associated with any disability in Chile, whereas material living conditions were partially confounded by these classic measures. In addition to this, each type of disability showed a particular pattern of related social determinants, which also varied by age group. This study contributed to the understanding of disability in Chile and how different domains of socioeconomic position might be associated with this prevalent condition. Disability remains a complex multidimensional public health problem in Chile that requires the inclusion of a wide range of risk factors, of which socioeconomic position is particularly relevant. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Common processes at unique volcanoes – a volcanological conundrum

    Directory of Open Access Journals (Sweden)

    Katharine eCashman

    2014-11-01

    Full Text Available An emerging challenge in modern volcanology is the apparent contradiction between the perception that every volcano is unique, and classification systems based on commonalities among volcano morphology and eruptive style. On the one hand, detailed studies of individual volcanoes show that a single volcano often exhibits similar patterns of behaviour over multiple eruptive episodes; this observation has led to the idea that each volcano has its own distinctive pattern of behaviour (or personality. In contrast, volcano classification schemes define eruption styles referenced to type volcanoes (e.g. Plinian, Strombolian, Vulcanian; this approach implicitly assumes that common processes underpin volcanic activity and can be used to predict the nature, extent and ensuing hazards of individual volcanoes. Actual volcanic eruptions, however, often include multiple styles, and type volcanoes may experience atypical eruptions (e.g., violent explosive eruptions of Kilauea, Hawaii1. The volcanological community is thus left with a fundamental conundrum that pits the uniqueness of individual volcanic systems against generalization of common processes. Addressing this challenge represents a major challenge to volcano research.

  5. Geochemical evolution of the acid crater lake of Poas volcano (Costa Rica): Insights into volcanic-hydrothermal processes

    NARCIS (Netherlands)

    Martínez Cruz, María

    2008-01-01

    This thesis describes the evolution of Laguna Caliente, an acid crater lake at the summit of Po:is, a persistently active volcano in central Costa Rica. The appearance, volume, temperature and chemical composition of the lake have continuously changed over the entire known period of its

  6. The role of viscous magma mush spreading in volcanic flank motion at Kīlauea Volcano, Hawai'i

    NARCIS (Netherlands)

    Plattner, C.; Amelung, F.; Baker, S.; Govers, R.; Poland, M.

    2013-01-01

    Multiple mechanisms have been suggested to explain seaward motion of the south flank of Kīlauea Volcano, Hawai'i. The consistency of flank motion during both waxing and waning magmatic activity at Kīlauea suggests that a continuously acting force, like gravity body force, plays a substantial role.

  7. Magma-carbonate interaction processes and associated CO2 release at Merapi volcano, Indonesia: insights from experimental petrology

    NARCIS (Netherlands)

    Deegan, F.M.; Troll, V.R.; Freda, C.; Misti, V.; Chadwick, J.P.

    2010-01-01

    There is considerable evidence for continuing, late-stage interaction between the magmatic system at Merapi volcano, Indonesia, and local crustal carbonate (limestone). Calc-silicate xenoliths within Merapi basaltic-andesite eruptive rocks display textures indicative of intense interaction between

  8. Regiones-commodities: Crisis y contagio en Chile

    Directory of Open Access Journals (Sweden)

    Antonio Daher

    2003-05-01

    Full Text Available La hipótesis de un nuevo dualismo entre una capital subglobal y sus "regiones-commodities" subyace en el estudio del impacto diferencial de las tres últimas crisis internacionales en las regiones de Chile, cuantificado a través de cuatro indicadores: el producto, el empleo, la inversión externa y las exportaciones, cuya variación permite verificar la disímil vulnerabilidad de cada región y su desigual exposición al riesgo de contagio de crisis. Fundamentado en un marco conceptual que sostiene que las crisis siguen siendo más regionales que globales, y que existe una verdadera geografía del contagio, el estudio muestra evidencia empírica que permite constatar: 1 la reproducción de un desbalance norte-sur al interior de Chile; 2 la doble paradoja de Santiago, cuya economía es la más diversificada y la más vulnerable, la más recesiva y la de mayor crecimiento; 3 la emergencia de Antofagasta como segunda economía regional de Chile, desplazando a Valparaíso y Concepción; 4 el paralelismo de Santiago y Antofagasta como regiones con el mayor producto, la mayor inversión extranjera y mayores exportaciones; y 5 la "mercosurización" de Santiago, capital subglobal, y la globalización de sus "regiones-commodities".The hypothesis of a new dualism between a sub-global capital city and its "commodities regions" underlies the study of the differential impact of the three last international crises on the regions of Chile. This impact is quantified through four indicators: product, employment, foreign investment and exports, and their variability allow the verification of the dissimilar vulnerability of each region and its dissimilar exposure to the risk of crisis contamination. The study is based on a conceptual frame that states that crisis continue to be more regional-like than global, and that there is a real geography of contamination. On the other hand, this study shows empirical evidence which makes it possible to verify: 1 the

  9. [Medical specialization in Chile. A centralized vision].

    Science.gov (United States)

    Clouet-Huerta, Diego E; González, Bárbara; Correa, Katherine

    2017-11-01

    Medical graduates face different postgraduate training options, but their priority is to obtain a primary medical specialty, defined as a specialty that does not derive from other. There are different specialty training programs in Chile, which can be dependent or independent of the Ministry of Health. The information about these programs is available in different Internet sites. However a centralized information service that groups and synthetize these programs is lacking, hampering graduate choice decisions. This article aims to review all specialization program modalities, providing a general vision of the institutional structure and implications that govern the specialization process in Chile.

  10. The "Mud-volcanoes route" (Emilia Apennines, northern Italy)

    Science.gov (United States)

    Coratza, Paola; Castaldini, Doriano

    2016-04-01

    In the present paper the "Mud-volcanoes route" (MVR), an itinerary unfolds across the districts of Viano, Sassuolo, Fiorano Modenese and Maranello, in which part of the Emilia mud volcanoes fields are located, is presented. The Mud-volanoes route represents an emotional journey that connects places and excellences through the geological phenomenon of mud volcanoes, known with the local name "Salse". The Mud Volcanoes are created by the surfacing of salt water and mud mixed with gaseous and liquid hydrocarbons along faults and fractures of the ground. The name "Salsa"- from Latin salsus - results from the"salt" content of these muddy waters, ancient heritage of the sea that about a million years ago was occupying the current Po Plain. The "Salse" may take the shape of a cone or a level-pool according to the density of the mud. The Salse of Nirano, in the district of Fiorano Modenese, is one of the most important in Italy and among the most complex in Europe. Less extensive but equally charming and spectacular, are the "Salse" located in the districts of Maranello (locality Puianello), Sassuolo (locality Montegibbio) and Viano (locality Casola Querciola and Regnano). These fascinating lunar landscapes have always attracted the interest of researchers and tourist.The presence on the MVR territory of ancient settlements, Roman furnaces and mansions, fortification systems and castles, besides historic and rural buildings, proves the lasting bond between this land and its men. In these places, where the culture of good food has become a resource, we can find wine cellars, dairy farms and Balsamic vinegar factories that enable us to appreciate unique worldwide products. This land gave also birth to some personalities who created unique worldwide famous values, such as the myth of the Ferrrari, the ceramic industry and the mechatronics. The MVR is represented in a leaflet containing, short explanation, photos and a map in which are located areas with mud volcanoes, castles

  11. Internet-accessible, near-real-time volcano monitoring data for geoscience education: the Volcanoes Exploration Project—Pu`u `O`o

    Science.gov (United States)

    Poland, M. P.; Teasdale, R.; Kraft, K.

    2010-12-01

    Internet-accessible real- and near-real-time Earth science datasets are an important resource for geoscience education, but relatively few comprehensive datasets are available, and background information to aid interpretation is often lacking. In response to this need, the U.S. Geological Survey’s (USGS) Hawaiian Volcano Observatory, in collaboration with the National Aeronautics and Space Administration and the University of Hawai‘i, Mānoa, established the Volcanoes Exploration Project: Pu‘u ‘O‘o (VEPP). The VEPP Web site provides access, in near-real time, to geodetic, seismic, and geologic data from the Pu‘u ‘O‘o eruptive vent on Kilauea Volcano, Hawai‘i. On the VEPP Web site, a time series query tool provides a means of interacting with continuous geophysical data. In addition, results from episodic kinematic GPS campaigns and lava flow field maps are posted as data are collected, and archived Webcam images from Pu‘u ‘O‘o crater are available as a tool for examining visual changes in volcanic activity over time. A variety of background information on volcano surveillance and the history of the 1983-present Pu‘u ‘O‘o-Kupaianaha eruption puts the available monitoring data in context. The primary goal of the VEPP Web site is to take advantage of high visibility monitoring data that are seldom suitably well-organized to constitute an established educational resource. In doing so, the VEPP project provides a geoscience education resource that demonstrates the dynamic nature of volcanoes and promotes excitement about the process of scientific discovery through hands-on learning. To support use of the VEPP Web site, a week-long workshop was held at Kilauea Volcano in July 2010, which included 25 participants from the United States and Canada. The participants represented a diverse cross-section of higher learning, from community colleges to research universities, and included faculty who teach both large introductory non-major classes

  12. Vocanic Deformations During Repose Interval Revealed by GPS Measurements, Batur Volcano, Indonesia

    Science.gov (United States)

    Nishimae, K.; Fujii, N.; Kimata, F.; Murase, M.; Suganda, O. K.; Abidin, H. Z.

    2005-12-01

    Batur volcano is located north west of Bali Island in Indonesia.This volcano has two calderas with more than 10 km in diameter. Recent eruptions with lava flow occurred in 1963 and 1974. No effusion of lava has been observed since 1990, although steam explosions occurred August 1994, November 1997 and June 1998.This suggests that magmatic activity of this volcano would keep its high level since 1994.GPS observation network of this volcano has been kept by Institute Technology of Bandung (ITB) and Volcano Survey of Indonesia (VSI).The network was consisted of 10 observation points at the beginning in 1999, and now it becomes 23 observation points. We have made GPS campaign observations about five times from 2003 to 2005. Each campaign observation consisted of a couple of days of measurements for each observation point. In order to keep the quality of data as high as possible, observations have been made at least 12 hours of continuous data for each point. In this report, results of two campaign observations (December 2004 and July 2005) are used for the analysis. The data thus obtained are fitted to the Mogi source (i.e. a point source model) to locate the depth and amount of volume changes for 7 months. Location of the Mogi source was obtained about 4km southeast of the summit of central cone, and 3km depth with deflation volume change of 1.3_~106 m3 for about 7months. For the period from 1999 to 2004, estimated volume change suggests a continuous deflation throughout this period, although the reliability of data was not so high. Continuous deflations might be likely after the last effusive eruption in 1974, would suggest that shallow part of magma beneath the central cone would probably be drained down to further deep, or shrinkage of magma associated with the cooling or solidification. Further data are obviously needed to discriminate the mechanisms of the deformation process during the repose period in this volcano.

  13. The story of the Hawaiian Volcano Observatory -- A remarkable first 100 years of tracking eruptions and earthquakes

    Science.gov (United States)

    Babb, Janet L.; Kauahikaua, James P.; Tilling, Robert I.

    2011-01-01

    The year 2012 marks the centennial of the Hawaiian Volcano Observatory (HVO). With the support and cooperation of visionaries, financiers, scientists, and other individuals and organizations, HVO has successfully achieved 100 years of continuous monitoring of Hawaiian volcanoes. As we celebrate this milestone anniversary, we express our sincere mahalo—thanks—to the people who have contributed to and participated in HVO’s mission during this past century. First and foremost, we owe a debt of gratitude to the late Thomas A. Jaggar, Jr., the geologist whose vision and efforts led to the founding of HVO. We also acknowledge the pioneering contributions of the late Frank A. Perret, who began the continuous monitoring of Kīlauea in 1911, setting the stage for Jaggar, who took over the work in 1912. Initial support for HVO was provided by the Massachusetts Institute of Technology (MIT) and the Carnegie Geophysical Laboratory, which financed the initial cache of volcano monitoring instruments and Perret’s work in 1911. The Hawaiian Volcano Research Association, a group of Honolulu businessmen organized by Lorrin A. Thurston, also provided essential funding for HVO’s daily operations starting in mid-1912 and continuing for several decades. Since HVO’s beginning, the University of Hawaiʻi (UH), called the College of Hawaii until 1920, has been an advocate of HVO’s scientific studies. We have benefited from collaborations with UH scientists at both the Hilo and Mänoa campuses and look forward to future cooperative efforts to better understand how Hawaiian volcanoes work. The U.S. Geological Survey (USGS) has operated HVO continuously since 1947. Before then, HVO was under the administration of various Federal agencies—the U.S. Weather Bureau, at the time part of the Department of Agriculture, from 1919 to 1924; the USGS, which first managed HVO from 1924 to 1935; and the National Park Service from 1935 to 1947. For 76 of its first 100 years, HVO has been

  14. The isotope systematics of a juvenile intraplate volcano: Pb, Nd, and Srisotope ratios of basalts from Loihi Seamount, Hawaii

    International Nuclear Information System (INIS)

    Staudigel, H.; Zindler, A.; Leslie, T.

    1984-01-01

    Sr, Nd, and Pb isotope ratios for a representative suite of 15 basanites, alkali basalts, transitional basalts and tholeiites from Loihi Seamount, Hawaii, display unusually large variations for a single volcano, but lie within known ranges for Hawaiian basalts. Nd isotope ratios in alkali basalts show the largest relative variation (0.51291 - 0.51305), and include the nearly constant tholeiite value (approx.= 0.51297). Pb isotope ratios show similarly large ranges for tholeiites and alkali basalts and continue Tatsumoto's [31] 'Loa' trend towards higher 206 Pb/ 204 Pb, ratios, resulting in a substantial overlap with the 'Kea' trend. 206 Pb/ 204 Pb ratios for Loihi and other volcanoes along the Loa and Kea trends [31] are observed to correlate with the age of the underlying lithosphere suggesting lithosphere involvement in the formation of Hawaiian tholeiites. Loihi lavas display no correlation of Nd, Sr, or Pb isotope ratios with major element compositions or eruptive age, in contrast with observations of some other Hawaiian volcanoes. Isotope data for Loihi, as well as average values for Hawaiian volcanoes, are not adequately explained by previously proposed two-end-member models; new models for the origin and the development of Hawaiian volcanoes must include mixing of at least three geochemically distinct source regions and allow for the involvement of heterogeneous oceanic lithosphere. (orig.)

  15. Inventory of gas flux measurements from volcanoes of the global Network for Observation of Volcanic and Atmospheric Change (NOVAC)

    Science.gov (United States)

    Galle, B.; Arellano, S.; Norman, P.; Conde, V.

    2012-04-01

    NOVAC, the Network for Observation of Volcanic and Atmospheric Change, was initiated in 2005 as a 5-year-long project financed by the European Union. Its main purpose is to create a global network for the monitoring and research of volcanic atmospheric plumes and related geophysical phenomena by using state-of-the-art spectroscopic remote sensing technology. Up to 2012, 64 instruments have been installed at 24 volcanoes in 13 countries of Latin America, Italy, Democratic Republic of Congo, Reunion, Iceland, and Philippines, and efforts are being done to expand the network to other active volcanic zones. NOVAC has been a pioneer initiative in the community of volcanologists and embraces the objectives of the Word Organization of Volcano Observatories (WOVO) and the Global Earth Observation System of Systems (GEOSS). In this contribution, we present the results of the measurements of SO2 gas fluxes carried out within NOVAC, which for some volcanoes represent a record of more than 7 years of continuous monitoring. The network comprises some of the most strongly degassing volcanoes in the world, covering a broad range of tectonic settings, levels of unrest, and potential risk. We show a global perspective of the output of volcanic gas from the covered regions, specific trends of degassing for a few selected volcanoes, and the significance of the database for further studies in volcanology and other geosciences.

  16. 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

  17. Decision Analysis Tools for Volcano Observatories

    Science.gov (United States)

    Hincks, T. H.; Aspinall, W.; Woo, G.

    2005-12-01

    Staff at volcano observatories are predominantly engaged in scientific activities related to volcano monitoring and instrumentation, data acquisition and analysis. Accordingly, the academic education and professional training of observatory staff tend to focus on these scientific functions. From time to time, however, staff may be called upon to provide decision support to government officials responsible for civil protection. Recognizing that Earth scientists may have limited technical familiarity with formal decision analysis methods, specialist software tools that assist decision support in a crisis should be welcome. A review is given of two software tools that have been under development recently. The first is for probabilistic risk assessment of human and economic loss from volcanic eruptions, and is of practical use in short and medium-term risk-informed planning of exclusion zones, post-disaster response, etc. A multiple branch event-tree architecture for the software, together with a formalism for ascribing probabilities to branches, have been developed within the context of the European Community EXPLORIS project. The second software tool utilizes the principles of the Bayesian Belief Network (BBN) for evidence-based assessment of volcanic state and probabilistic threat evaluation. This is of practical application in short-term volcano hazard forecasting and real-time crisis management, including the difficult challenge of deciding when an eruption is over. An open-source BBN library is the software foundation for this tool, which is capable of combining synoptically different strands of observational data from diverse monitoring sources. A conceptual vision is presented of the practical deployment of these decision analysis tools in a future volcano observatory environment. Summary retrospective analyses are given of previous volcanic crises to illustrate the hazard and risk insights gained from use of these tools.

  18. Geothermal Exploration of Newberry Volcano, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    Waibel, Albert F. [Columbia Geoscience, Pasco, WA (United States); Frone, Zachary S. [Southern Methodist Univ., Dallas, TX (United States); Blackwell, David D. [Southern Methodist Univ., Dallas, TX (United States)

    2014-12-01

    Davenport Newberry (Davenport) has completed 8 years of exploration for geothermal energy on Newberry Volcano in central Oregon. Two deep exploration test wells were drilled by Davenport on the west flank of the volcano, one intersected a hydrothermal system; the other intersected isolated fractures with no hydrothermal interconnection. Both holes have bottom-hole temperatures near or above 315°C (600°F). Subsequent to deep test drilling an expanded exploration and evaluation program was initiated. These efforts have included reprocessing existing data, executing multiple geological, geophysical, geochemical programs, deep exploration test well drilling and shallow well drilling. The efforts over the last three years have been made possible through a DOE Innovative Exploration Technology (IET) Grant 109, designed to facilitate innovative geothermal exploration techniques. The combined results of the last 8 years have led to a better understanding of the history and complexity of Newberry Volcano and improved the design and interpretation of geophysical exploration techniques with regard to blind geothermal resources in volcanic terrain.

  19. Electrical structure of Newberry Volcano, Oregon

    Science.gov (United States)

    Fitterman, D.V.; Stanley, W.D.; Bisdorf, R.J.

    1988-01-01

    From the interpretation of magnetotelluric, transient electromagnetic, and Schlumberger resistivity soundings, the electrical structure of Newberry Volcano in central Oregon is found to consist of four units. From the surface downward, the geoelectrical units are 1) very resistive, young, unaltered volcanic rock, (2) a conductive layer of older volcanic material composed of altered tuffs, 3) a thick resistive layer thought to be in part intrusive rocks, and 4) a lower-crustal conductor. This model is similar to the regional geoelectrical structure found throughout the Cascade Range. Inside the caldera, the conductive second layer corresponds to the steep temperature gradient and alteration minerals observed in the USGS Newberry 2 test-hole. Drill hole information on the south and north flanks of the volcano (test holes GEO N-1 and GEO N-3, respectively) indicates that outside the caldera the conductor is due to alteration minerals (primarily smectite) and not high-temperature pore fluids. On the flanks of Newberry the conductor is generally deeper than inside the caldera, and it deepens with distance from the summit. A notable exception to this pattern is seen just west of the caldera rim, where the conductive zone is shallower than at other flank locations. The volcano sits atop a rise in the resistive layer, interpreted to be due to intrusive rocks. -from Authors

  20. Monitoring active volcanoes: The geochemical approach

    Directory of Open Access Journals (Sweden)

    Takeshi Ohba

    2011-06-01

    Full Text Available

    The geochemical surveillance of an active volcano aims to recognize possible signals that are related to changes in volcanic activity. Indeed, as a consequence of the magma rising inside the volcanic "plumbing system" and/or the refilling with new batches of magma, the dissolved volatiles in the magma are progressively released as a function of their relative solubilities. When approaching the surface, these fluids that are discharged during magma degassing can interact with shallow aquifers and/or can be released along the main volcano-tectonic structures. Under these conditions, the following main degassing processes represent strategic sites to be monitored.

    The main purpose of this special volume is to collect papers that cover a wide range of topics in volcanic fluid geochemistry, which include geochemical characterization and geochemical monitoring of active volcanoes using different techniques and at different sites. Moreover, part of this volume has been dedicated to the new geochemistry tools.

  1. Nanoscale volcanoes: accretion of matter at ion-sculpted nanopores.

    Science.gov (United States)

    Mitsui, Toshiyuki; Stein, Derek; Kim, Young-Rok; Hoogerheide, David; Golovchenko, J A

    2006-01-27

    We demonstrate the formation of nanoscale volcano-like structures induced by ion-beam irradiation of nanoscale pores in freestanding silicon nitride membranes. Accreted matter is delivered to the volcanoes from micrometer distances along the surface. Volcano formation accompanies nanopore shrinking and depends on geometrical factors and the presence of a conducting layer on the membrane's back surface. We argue that surface electric fields play an important role in accounting for the experimental observations.

  2. Sistema de salud de Chile The health system of Chile

    Directory of Open Access Journals (Sweden)

    Víctor Becerril-Montekio

    2011-01-01

    Full Text Available En este trabajo se describe el sistema de salud de Chile, incluyendo su estructura, financiamiento, beneficiarios y recursos físicos, materiales y humanos de los que dispone. Este sistema está compuesto por dos sectores, público y privado. El sector público está formado por todos los organismos que constituyen el Sistema Nacional de Servicios de Salud y cubre aproximadamente a 70% de la población, incluyendo a los pobres del campo y las ciudades, la clase media baja y los jubilados, así como los profesionales y técnicos. El sector privado cubre aproximadamente a 17.5% de la población perteneciente a los grupos sociales de mayores ingresos. Un pequeño sector de la población, perteneciente a la clase alta, realiza pagos directos de bolsillo a proveedores privados de servicios de atención a la salud. Alrededor de 10% de la población está cubierta por otras agencias públicas, fundamentalmente los Servicios de Salud de las Fuerzas Armadas. Recientemente el sistema se reformó creando el Régimen General de Garantías en Salud, que establece un Sistema Universal con Garantías Explícitas que se tradujo, en 2005, en el Plan de Acceso Universal con Garantías Explícitas (AUGE, que garantiza el acceso oportuno a servicios de calidad para 56 problemas de salud, incluyendo cáncer en niños, cáncer de mama, trastornos isquémicos del corazón, VIH/SIDA y diabetes.This paper describes the Chilean health system, including its structure, financing, beneficiaries, and its physical, material and human resources. This system has two sectors, public and private. The public sector comprises all the organisms that constitute the National System of Health Services, which covers 70% of the population, including the rural and urban poor, the low middle-class, the retired, and the self-employed professionals and technicians.The private sector covers 17.5% of the population, mostly the upper middle-class and the high-income population. A small

  3. Nuclear public information activities in Chile

    International Nuclear Information System (INIS)

    Munoz Quintana; R

    1995-01-01

    Nuclear plans and developing programs in developing and developed countries are facing-in a higher or lower degree- opposition from public opinion. The objectives and contents of the public education program on nuclear energy in Chile are dealt with in this paper

  4. Doing Business 2014 Economy Profile : Chile

    OpenAIRE

    World Bank; International Finance Corporation

    2013-01-01

    This economy profile presents the Doing Business indicators for Chile In a series of annual reports, Doing Business assesses regulations affecting domestic firms in 189 economies and ranks the economies in 10 areas of business regulation, such as starting a business, resolving insolvency and trading across borders. This year's report data cover regulations measured from June 2012 through M...

  5. A solar radiation database for Chile.

    Science.gov (United States)

    Molina, Alejandra; Falvey, Mark; Rondanelli, Roberto

    2017-11-01

    Chile hosts some of the sunniest places on earth, which has led to a growing solar energy industry in recent years. However, the lack of high resolution measurements of solar irradiance becomes a critical obstacle for both financing and design of solar installations. Besides the Atacama Desert, Chile displays a large array of "solar climates" due to large latitude and altitude variations, and so provides a useful testbed for the development of solar irradiance maps. Here a new public database for surface solar irradiance over Chile is presented. This database includes hourly irradiance from 2004 to 2016 at 90 m horizontal resolution over continental Chile. Our results are based on global reanalysis data to force a radiative transfer model for clear sky solar irradiance and an empirical model based on geostationary satellite data for cloudy conditions. The results have been validated using 140 surface solar irradiance stations throughout the country. Model mean percentage error in hourly time series of global horizontal irradiance is only 0.73%, considering both clear and cloudy days. The simplicity and accuracy of the model over a wide range of solar conditions provides confidence that the model can be easily generalized to other regions of the world.

  6. DEZVOLTAREA CONTEMPORANĂ A TURISMULUI DIN CHILE

    Directory of Open Access Journals (Sweden)

    Maria-Mihaela Győri

    2011-01-01

    Full Text Available The contemporary development of the Chilean Tourism sector is analyzed mainly on thebasis of data supplied by the National Service of Tourism in Chile. Figures on inboundtourism, domestic tourism, lodging, employment, receipts, as well as the existing structurewithin the sector, were taken into consideration for the investigated period of 1999-2006.

  7. [Notes about other epidemics in Colonial Chile].

    Science.gov (United States)

    Laval, Enrique

    2015-10-01

    In chronicles or in the historiography of the Colony in Chile there are few references about epidemics different to smallpox; like typhus, typhoid fever, dysentery, etc. Almost all, fast spreading in the country and some with high lethality, which led to overflowing the capacity of hospitals in the Chilean colonial period.

  8. Soviet Policy in Cuba and Chile.

    Science.gov (United States)

    1980-05-06

    critical stance to the USSR for much of the rest of the decade. Along with Castro’s efforts to establish the Cuban experience of a rural guerrilla-based...Neresidades de Financamento Externo parea el Desarrollo de Chile, January 28. 1974, p. V-9. 17. New aid loans from the United States declined to $S.5 million

  9. Deformation at Lava Lake Volcanoes: Lessons from Karthala

    Science.gov (United States)

    Biggs, J.; Rust, A.; Owens, C.

    2014-12-01

    To remain hot, permanent lava lakes require a continuous connection to a magma reservoir. Depending on the state of the conduit, changes in magma pressure could result in changes in the lake level (hydraulic head) or be accommodated elastically leading to surface deformation. Observing deformation is therefore key to understanding the plumbing system associated with lava lakes. However, the majority of the world's lava lakes lie in difficult socio-economic or remote locations meaning that there are few ground-based observations, and it is often necessary to rely on satellite imagery. Karthala volcano experienced a sequence of eruptions in April 2005, Nov 2005, May 2006 and Jan 2007. The first 3 took place at the Choungou Chahale crater, which typically contains either a water or lava lake; the last formed a new pit crater to the north. Satellite thermal imagery (Hirn et al, 2008) does not show an anomaly during the first eruption, which had a phreatomagmatic component, but large thermal anomalies, associated with an ephemeral lava lake were detected during the Nov 2005 and May 2006 eruptions. The final eruption produced a smaller anomaly attributed to a minor lava flow. Here we present InSAR observations from 2004-2010. We find no significant deformation associated with the first three eruptions, but the January 2007 eruption was associated with ~25 cm of deformation near the volcano's summit, characteristic of a dyke intrusion aligned with the northern rift zone. We also observe an unusual pattern deformation along the coast which may be attributed to rapid settling of soft sediment or recent volcanic deposits triggered by seismic activity. We propose that the first eruption cleared the reservoir-summit connection and interacted with the water in Choungou Chahale. The following eruptions formed a lava lake, but without causing deformation. By the final eruption, the conduit had become blocked and magma intruded along the rift zone causing deformation but no

  10. [The 140th anniversary of Revista Médica de Chile].

    Science.gov (United States)

    Reyes, B Humberto; Andresen, H Max; Palma, H Joaquín

    2012-01-01

    Revista Médica de Chile was founded in 1872 and thus is one of the oldest medical journals being published since the 19th Century. The sponsoring institution--"Sociedad Médica de Santiago", founded in 1869--initially was the only scientific society in Chile, gathering medical doctors from every existing specialty. With the splitting of independent organizations representing specific specialties, including subspecial-ties of internal medicine, Sociedad Médica de Santiago focused its scope of action to become the "Chilean Society of Internal Medicine". Its official journal -Revista Médica de Chile--is currently a general and internal medicine journal that also publishes articles on scientific and technological advances in many fields of medicine and health sciences. While initially all authors were Chilean, the journal is now open to submissions from abroad and since the year 2000 articles are published in English when the local language of authors is not Spanish. The number of articles received determines an increasing administrative and editorial burden and, together with the high cost of publishing, will require changes in publication policies. The journal will participate in continuing medical education programs as soon as reaccreditation of medical specialties becomes officially organized in Chile.

  11. Efficient inversion of volcano deformation based on finite element models : An application to Kilauea volcano, Hawaii

    Science.gov (United States)

    Charco, María; González, Pablo J.; Galán del Sastre, Pedro

    2017-04-01

    The Kilauea volcano (Hawaii, USA) is one of the most active volcanoes world-wide and therefore one of the better monitored volcanoes around the world. Its complex system provides a unique opportunity to investigate the dynamics of magma transport and supply. Geodetic techniques, as Interferometric Synthetic Aperture Radar (InSAR) are being extensively used to monitor ground deformation at volcanic areas. The quantitative interpretation of such surface ground deformation measurements using geodetic data requires both, physical modelling to simulate the observed signals and inversion approaches to estimate the magmatic source parameters. Here, we use synthetic aperture radar data from Sentinel-1 radar interferometry satellite mission to image volcano deformation sources during the inflation along Kilauea's Southwest Rift Zone in April-May 2015. We propose a Finite Element Model (FEM) for the calculation of Green functions in a mechanically heterogeneous domain. The key aspect of the methodology lies in applying the reciprocity relationship of the Green functions between the station and the source for efficient numerical inversions. The search for the best-fitting magmatic (point) source(s) is generally conducted for an array of 3-D locations extending below a predefined volume region. However, our approach allows to reduce the total number of Green functions to the number of the observation points by using the, above mentioned, reciprocity relationship. This new methodology is able to accurately represent magmatic processes using physical models capable of simulating volcano deformation in non-uniform material properties distribution domains, which eventually will lead to better description of the status of the volcano.

  12. Geologic map of Medicine Lake volcano, northern California

    Science.gov (United States)

    Donnelly-Nolan, Julie M.

    2011-01-01

    Medicine Lake volcano forms a broad, seemingly nondescript highland, as viewed from any angle on the ground. Seen from an airplane, however, treeless lava flows are scattered across the surface of this potentially active volcanic edifice. Lavas of Medicine Lake volcano, which range in composition from basalt through rhyolite, cover more than 2,000 km2 east of the main axis of the Cascade Range in northern California. Across the Cascade Range axis to the west-southwest is Mount Shasta, its towering volcanic neighbor, whose stratocone shape contrasts with the broad shield shape of Medicine Lake volcano. Hidden in the center of Medicine Lake volcano is a 7 km by 12 km summit caldera in which nestles its namesake, Medicine Lake. The flanks of Medicine Lake volcano, which are dotted with cinder cones, slope gently upward to the caldera rim, which reaches an elevation of nearly 8,000 ft (2,440 m). The maximum extent of lavas from this half-million-year-old volcano is about 80 km north-south by 45 km east-west. In postglacial time, 17 eruptions have added approximately 7.5 km3 to its total estimated volume of 600 km3, and it is considered to be the largest by volume among volcanoes of the Cascades arc. The volcano has erupted nine times in the past 5,200 years, a rate more frequent than has been documented at all other Cascades arc volcanoes except Mount St. Helens.

  13. The critical role of volcano monitoring in risk reduction

    Directory of Open Access Journals (Sweden)

    R. I. Tilling

    2008-01-01

    Full Text Available Data from volcano-monitoring studies constitute the only scientifically valid basis for short-term forecasts of a future eruption, or of possible changes during an ongoing eruption. Thus, in any effective hazards-mitigation program, a basic strategy in reducing volcano risk is the initiation or augmentation of volcano monitoring at historically active volcanoes and also at geologically young, but presently dormant, volcanoes with potential for reactivation. Beginning with the 1980s, substantial progress in volcano-monitoring techniques and networks – ground-based as well space-based – has been achieved. Although some geochemical monitoring techniques (e.g., remote measurement of volcanic gas emissions are being increasingly applied and show considerable promise, seismic and geodetic methods to date remain the techniques of choice and are the most widely used. Availability of comprehensive volcano-monitoring data was a decisive factor in the successful scientific and governmental responses to the reawakening of Mount St. elens (Washington, USA in 1980 and, more recently, to the powerful explosive eruptions at Mount Pinatubo (Luzon, Philippines in 1991. However, even with the ever-improving state-of-the-art in volcano monitoring and predictive capability, the Mount St. Helens and Pinatubo case histories unfortunately still represent the exceptions, rather than the rule, in successfully forecasting the most likely outcome of volcano unrest.

  14. Volcano-Monitoring Instrumentation in the United States, 2008

    Science.gov (United States)

    Guffanti, Marianne; Diefenbach, Angela K.; Ewert, John W.; Ramsey, David W.; Cervelli, Peter F.; Schilling, Steven P.

    2010-01-01

    The United States is one of the most volcanically active countries in the world. According to the global volcanism database of the Smithsonian Institution, the United States (including its Commonwealth of the Northern Mariana Islands) is home to about 170 volcanoes that are in an eruptive phase, have erupted in historical time, or have not erupted recently but are young enough (eruptions within the past 10,000 years) to be capable of reawakening. From 1980 through 2008, 30 of these volcanoes erupted, several repeatedly. Volcano monitoring in the United States is carried out by the U.S. Geological Survey (USGS) Volcano Hazards Program, which operates a system of five volcano observatories-Alaska Volcano Observatory (AVO), Cascades Volcano Observatory (CVO), Hawaiian Volcano Observatory (HVO), Long Valley Observatory (LVO), and Yellowstone Volcano Observatory (YVO). The observatories issue public alerts about conditions and hazards at U.S. volcanoes in support of the USGS mandate under P.L. 93-288 (Stafford Act) to provide timely warnings of potential volcanic disasters to the affected populace and civil authorities. To make efficient use of the Nation's scientific resources, the volcano observatories operate in partnership with universities and other governmental agencies through various formal agreements. The Consortium of U.S. Volcano Observatories (CUSVO) was established in 2001 to promote scientific cooperation among the Federal, academic, and State agencies involved in observatory operations. Other groups also contribute to volcano monitoring by sponsoring long-term installation of geophysical instruments at some volcanoes for specific research projects. This report describes a database of information about permanently installed ground-based instruments used by the U.S. volcano observatories to monitor volcanic activity (unrest and eruptions). The purposes of this Volcano-Monitoring Instrumentation Database (VMID) are to (1) document the Nation's existing

  15. [Human resources for health in Chile: the reform's pending challenge].

    Science.gov (United States)

    Méndez, Claudio A

    2009-09-01

    Omission of human resources from health policy development has been identified as a barrier in the health sector reform's adoption phase. Since 2002, Chile's health care system has been undergoing a transformation based on the principles of health as a human right, equity, solidarity, efficiency, and social participation. While the reform has set forth the redefinition of the medical professions, continuing education, scheduled accreditation, and the introduction of career development incentives, it has not considered management options tailored to the new setting, a human resources strategy that has the consensus of key players and sector policy, or a process for understanding the needs of health care staff and professionals. However, there is still time to undo the shortcomings, in large part because the reform's implementation phase only recently has begun. Overcoming this challenge is in the hands of the experts charged with designing public health strategies and policies.

  16. Business Incubation in Chile: Development, Financing and Financial Services

    Directory of Open Access Journals (Sweden)

    Aruna Chandra

    2012-07-01

    Full Text Available Business incubation in Chile is still in its nascent stages, with approximately 27 incubators supported primarily by a coalition of government and universities. Chilean business incubators tend to capitalize on regional resource strengths and have a strategic focus on high growth, high innovation, high impact businesses as a result of a government mandate to focus on developing business with high potential for economic development and job creation. The government’s efforts to create the framework conditions for entrepreneurship by investing in business incubators, organizing risk capital for early stage ventures to fill capital market gaps and support for angel networks as well as incubator funding are discussed. Policy implications for the continued growth of the incubation industry are provided.

  17. Cultural experiences of immigrant nurses at two hospitals in Chile.

    Science.gov (United States)

    Rodríguez, Gabriel; Angélica-Muñoz, Luz; Hoga, Luiza Akiko Komura

    2014-01-01

    to explore the cultural experiences of nurses who immigrated to Chile. The study's theoretical framework was the Purnell Model for Cultural Competence. Leininger's Observation-Participation-Reflection method was developed at two hospitals in the city of Santiago, and ethnographic interviews were held with 15 immigrant nurses. among Purnell's 12 domains, the following were identified: Overview/heritage, Communication, Workforce issues, Family roles and organization, Biocultural ecology and Health-care practices. The difficulties were related to the language and its semantic meaning, the new responsibilities and the difficult relationship with colleagues. "In search of better horizons - the decision to immigrate", "Gaining confidence and establishing a support network - employability and professional performance" and "Seeking for people's acceptance - professional adaptation in a new cultural scenario" are cultural themes that represent their experiences. the competence to offer cultural care demands the development of public policies and continuing education programs at health institutions, specifically focused on immigrant nurses.

  18. Developing geophysical monitoring at Mayon volcano, a collaborative project EOS-PHIVOLCS

    Science.gov (United States)

    Hidayat, D.; Laguerta, E.; Baloloy, A.; Valerio, R.; Marcial, S. S.

    2011-12-01

    Mayon is an openly-degassed volcano, producing mostly small, frequent eruptions, most recently in Aug-Sept 2006 and Dec 2009. Mayon volcano status is level 1 with low seismicity dominated mostly local and regional tectonic earthquakes with continuous emission of SO2 from its crater. A research collaboration between Earth Observatory of Singapore-NTU and Philippine Institute of Volcanology and Seismology (PHIVOLCS) have been initiated in 2010 with effort to develop a multi-disciplinary monitoring system around Mayon includes geophysical monitoring, gas geochemical monitoring, and petrologic studies. Currently there are 4 broadband seismographs, 3 short period instruments, and 4 tiltmeters. These instruments will be telemetered to the Lignon Hill Volcano Observatory through radio and 3G broadband internet. We also make use of our self-made low-cost datalogger which has been operating since Jan 2011, performing continuous data acquisition with sampling rate of 20 minute/sample and transmitted through gsm network. First target of this monitoring system is to obtain continuous multi parameter data transmitted in real time to the observatory from different instruments. Tectonically, Mayon is located in the Oas Graben, a northwest-trending structural depression. Previous study using InSAR data, showing evidence of a left-lateral oblique slip movement of the fault North of Mayon. Understanding on what structures active deformation is occurring and how deformation signal is currently partitioned between tectonic and volcanic origin is a key for characterizing magma movement in the time of unrest. Preliminary analysis of the tangential components of tiltmeters (particularly the stations 5 and 7.5 NE from the volcano) shows gradual inflation movement over a few months period. The tangential components for tiltmeters are roughly perpendicular to the fault north of Mayon. This may suggest downward tilting of the graben in the northern side of Mayon. Another possibility is that

  19. Comparison of six green chile (capsicum annum) cultivars for efficiency of Etgar® machine harvest

    Science.gov (United States)

    As U.S. demand for fresh market green chile rises green chile acreage in the U.S. is declining due to limited availability and high cost of hand labor to harvest it. Many farmers are opting to grow crops other than green chile. Green chile is a New Mexican pod-type chile that is harvested when the...

  20. Source model for the Copahue volcano magmaplumbing system constrained by InSARsurface deformation observations

    Science.gov (United States)

    Lundgren, P.; Nikkhoo, M.; Samsonov, S. V.; Milillo, P.; Gil-Cruz, F., Sr.; Lazo, J.

    2017-12-01

    Copahue volcano straddling the edge of the Agrio-Caviahue caldera along the Chile-Argentinaborder in the southern Andes has been in unrest since inflation began in late 2011. We constrain Copahue'ssource models with satellite and airborne interferometric synthetic aperture radar (InSAR) deformationobservations. InSAR time series from descending track RADARSAT-2 and COSMO-SkyMed data span theentire inflation period from 2011 to 2016, with their initially high rates of 12 and 15 cm/yr, respectively,slowing only slightly despite ongoing small eruptions through 2016. InSAR ascending and descending tracktime series for the 2013-2016 time period constrain a two-source compound dislocation model, with a rate ofvolume increase of 13 × 106 m3/yr. They consist of a shallow, near-vertical, elongated source centered at2.5 km beneath the summit and a deeper, shallowly plunging source centered at 7 km depth connecting theshallow source to the deeper caldera. The deeper source is located directly beneath the volcano tectonicseismicity with the lower bounds of the seismicity parallel to the plunge of the deep source. InSAR time seriesalso show normal fault offsets on the NE flank Copahue faults. Coulomb stress change calculations forright-lateral strike slip (RLSS), thrust, and normal receiver faults show positive values in the north caldera forboth RLSS and normal faults, suggesting that northward trending seismicity and Copahue fault motion withinthe caldera are caused by the modeled sources. Together, the InSAR-constrained source model and theseismicity suggest a deep conduit or transfer zone where magma moves from the central caldera toCopahue's upper edifice.

  1. A survey of volcano deformation in the central Andes using InSAR: Evidence for deep, slow inflation

    Science.gov (United States)

    Pritchard, M. E.; Simons, M.

    2001-12-01

    We use interferometric synthetic aperture radar (InSAR) to survey about 50 volcanos of the central Andes (15-27o S) for deformation during the 1992-2000 time interval. Because of the remote location of these volcanos, the activity of most are poorly constrained. Using the ERS-1/2 C-band radars (5.6 cm), we observe good interferometric correlation south of about 21o S, but poor correlation north of that latitude, especially in southern Peru. This variation is presumably related to regional climate variations. Our survey reveals broad (10's of km), roughly axisymmetric deformation at 2 volcanic centers with no previously documented deformation. At Uturuncu volcano, in southwestern Bolivia, the deformation rate can be constrained with radar data from several satellite tracks and is about 1 cm/year between 1992 and 2000. We find a second source of volcanic deformation located between Lastarria and Cordon del Azufre volcanos near the Chile/Argentina border. There is less radar data to constrain the deformation in this area, but the rate is also about 1 cm/yr between 1996 and 2000. While the spatial character of the deformation field appears to be affected by atmosphere at both locations, we do not think that the entire signal is atmospheric, because the signal is observed in several interferograms and nearby edifices do not show similar patterns. The deformation signal appears to be time-variable, although it is difficult to determine whether this is due to real variations in the deformation source or atmospheric effects. We model the deformation with both a uniform point-source source of inflation, and a tri-axial point-source ellipsoid, and compare both elastic half-space and layered-space models. We also explore the effects of local topography upon the deformation field using the method of Williams and Wadge (1998). We invert for source parameters using the global search Neighborhood Algorithm of Sambridge (1998). Preliminary results indicate that the sources at both

  2. Estado del conocimiento y principales amenazas de los humedales boscosos de agua dulce de Chile Knowledge status and principal threats to freshwater forested wetlands of Chile

    Directory of Open Access Journals (Sweden)

    FRANCISCO CORREA-ARANEDA

    2011-09-01

    en el tiempo.Forested freshwater wetlands are naturally flooded or saturated areas with hydrophilic forest vegetation which is worldwide distributed and is known as "pitrantos, hualves o hualhues" in Chile. This paper gives to know the state of art of these wetlands in Chile, through a description of its biological, physical-chemical and hydro-dynamic characteristics, identifying the main threats to its conservation and the main research needs. These environments can be permanently or temporarily flooded, depending on microclimatic, biological and edaphical processes. Its vegetation is dominated by species of the family Myrtaceae. Both hydric behavior and vegetation structure are major aspects that directly determine the water physical-chemical characteristics and the distribution patterns of biological communities. Chile's forested wetlands have been studied broadly from a vegetation and floristic point of view, but basic studies on limnology, hydrology or fauna are lacking, which results on a total lack of knowledge about its functioning at the ecosystem level and the effects that human activities on basins (e.g., agricultural, stockbreeding, forest could have on its hydric and biological components. In spite of being ecosystems of great cultural and ecological significance, important weakness can be identified on its state of conservation, as they are not protected by conservation tools that exist in Chile nowadays. Therefore, forested wetlands emerge as unique ecosystems of global importance, nearly unknown in Chile and of great interest on developing an important number of research lines, even though their high susceptibility facing anthropic disturbances threaten their continuance.

  3. Preliminary Volcano-Hazard Assessment for Gareloi Volcano, Gareloi Island, Alaska

    Science.gov (United States)

    Coombs, Michelle L.; McGimsey, Robert G.; Browne, Brandon L.

    2008-01-01

    Gareloi Volcano (178.794 degrees W and 51.790 degrees N) is located on Gareloi Island in the Delarof Islands group of the Aleutian Islands, about 2,000 kilometers west-southwest of Anchorage and about 150 kilometers west of Adak, the westernmost community in Alaska. This small (about 8x10 kilometer) volcano has been one of the most active in the Aleutians since its discovery by the Bering expedition in the 1740s, though because of its remote location, observations have been scant and many smaller eruptions may have gone unrecorded. Eruptions of Gareloi commonly produce ash clouds and lava flows. Scars on the flanks of the volcano and debris-avalanche deposits on the adjacent seafloor indicate that the volcano has produced large landslides in the past, possibly causing tsunamis. Such events are infrequent, occurring at most every few thousand years. The primary hazard from Gareloi is airborne clouds of ash that could affect aircraft. In this report, we summarize and describe the major volcanic hazards associated with Gareloi.

  4. Volcano art at Hawai`i Volcanoes National Park—A science perspective

    Science.gov (United States)

    Gaddis, Ben; Kauahikaua, James P.

    2018-03-26

    Long before landscape photography became common, artists sketched and painted scenes of faraway places for the masses. Throughout the 19th century, scientific expeditions to Hawaiʻi routinely employed artists to depict images for the people back home who had funded the exploration and for those with an interest in the newly discovered lands. In Hawaiʻi, artists portrayed the broad variety of people, plant and animal life, and landscapes, but a feature of singular interest was the volcanoes. Painters of early Hawaiian volcano landscapes created art that formed a cohesive body of work known as the “Volcano School” (Forbes, 1992). Jules Tavernier, Charles Furneaux, and D. Howard Hitchcock were probably the best known artists of this school, and their paintings can be found in galleries around the world. Their dramatic paintings were recognized as fine art but were also strong advertisements for tourists to visit Hawaiʻi. Many of these masterpieces are preserved in the Museum and Archive Collection of Hawaiʻi Volcanoes National Park, and in this report we have taken the opportunity to match the artwork with the approximate date and volcanological context of the scene.

  5. Evolution of deep crustal magma structures beneath Mount Baekdu volcano (MBV) intraplate volcano in northeast Asia

    Science.gov (United States)

    Rhie, J.; Kim, S.; Tkalcic, H.; Baag, S. Y.

    2017-12-01

    Heterogeneous features of magmatic structures beneath intraplate volcanoes are attributed to interactions between the ascending magma and lithospheric structures. Here, we investigate the evolution of crustal magmatic stuructures beneath Mount Baekdu volcano (MBV), which is one of the largest continental intraplate volcanoes in northeast Asia. The result of our seismic imaging shows that the deeper Moho depth ( 40 km) and relatively higher shear wave velocities (>3.8 km/s) at middle-to-lower crustal depths beneath the volcano. In addition, the pattern at the bottom of our model shows that the lithosphere beneath the MBV is shallower (interpret the observations as a compositional double layering of mafic underplating and a overlying cooled felsic structure due to fractional crystallization of asthenosphere origin magma. To achieve enhanced vertical and horizontal model coverage, we apply two approaches in this work, including (1) a grid-search based phase velocity measurement using real-coherency of ambient noise data and (2) a transdimensional Bayesian joint inversion using multiple ambient noise dispersion data.

  6. Understanding cyclic seismicity and ground deformation patterns at volcanoes: Intriguing lessons from Tungurahua volcano, Ecuador

    Science.gov (United States)

    Neuberg, Jürgen W.; Collinson, Amy S. D.; Mothes, Patricia A.; Ruiz, Mario C.; Aguaiza, Santiago

    2018-01-01

    Cyclic seismicity and ground deformation patterns are observed on many volcanoes worldwide where seismic swarms and the tilt of the volcanic flanks provide sensitive tools to assess the state of volcanic activity. Ground deformation at active volcanoes is often interpreted as pressure changes in a magmatic reservoir, and tilt is simply translated accordingly into inflation and deflation of such a reservoir. Tilt data recorded by an instrument in the summit area of Tungurahua volcano in Ecuador, however, show an intriguing and unexpected behaviour on several occasions: prior to a Vulcanian explosion when a pressurisation of the system would be expected, the tilt signal declines significantly, hence indicating depressurisation. At the same time, seismicity increases drastically. Envisaging that such a pattern could carry the potential to forecast Vulcanian explosions on Tungurahua, we use numerical modelling and reproduce the observed tilt patterns in both space and time. We demonstrate that the tilt signal can be more easily explained as caused by shear stress due to viscous flow resistance, rather than by pressurisation of the magmatic plumbing system. In general, our numerical models prove that if magma shear viscosity and ascent rate are high enough, the resulting shear stress is sufficient to generate a tilt signal as observed on Tungurahua. Furthermore, we address the interdependence of tilt and seismicity through shear stress partitioning and suggest that a joint interpretation of tilt and seismicity can shed new light on the eruption potential of silicic volcanoes.

  7. Managing the effects of accelerated glacial melting on volcanic collapse and debris flows: Planchon-Peteroa Volcano, Southern Andes

    Science.gov (United States)

    Tormey, Daniel

    2010-11-01

    Glaciated mountains are among the most sensitive environments to climatic changes, and recent work has shown that large-scale glacial melting, including at the end of the Pleistocene, caused a significant increase in the incidence of large volcanic sector collapse and debris flows on then-active volcanoes. With current accelerated rates of glacial melting, glaciated active volcanoes are at an increasing risk of sector collapse, debris flow and landslide. These catastrophic events are Earth's most damaging erosion phenomenon, causing extensive property damage and loss of life. This paper illustrates these effects in well-studied settings, focusing on the end-Pleistocene to Holocene glaciovolcanic growth and destruction of the cone of the active volcano Planchon-Peteroa in the Andean Southern Volcanic Zone at latitude 35° 15' S, along the border between Chile and Argentina. The development of the volcano over the last 14,000 years illustrates how glacial melting and magmatic activity can trigger landslides and sector collapses. Planchon had a large sector collapse that produced a highly mobile and erosive debris avalanche 11,000 years BP, and other slope instabilities during the end-Pleistocene/early Holocene deglaciation. The summit amphitheater left after the sector collapse was subject to alternating periods of glaciation and melting-induced lake formation. Breaching of the moraine dams then formed lahars and landslides originating at the western edge of the summit amphitheater, and the deposits are preserved along the western flank of the volcano. Deep incision of moraine deposits further down the western slope of the volcano indicates that the lahars and landslides were water-rich and had high erosive power. As illustrated by Planchon-Peteroa, the interplay among glacial growth and melting, magmatic activity, and slope stability is complex, but must be accounted for in volcanic hazard assessment. Planchon-Peteroa currently has the southernmost temperate zone

  8. Imaging magma plumbing beneath Askja volcano, Iceland

    Science.gov (United States)

    Greenfield, Tim; White, Robert S.

    2015-04-01

    Volcanoes during repose periods are not commonly monitored by dense instrumentation networks and so activity during periods of unrest is difficult to put in context. We have operated a dense seismic network of 3-component, broadband instruments around Askja, a large central volcano in the Northern Volcanic Zone, Iceland, since 2006. Askja last erupted in 1961, with a relatively small basaltic lava flow. Since 1975 the central caldera has been subsiding and there has been no indication of volcanic activity. Despite this, Askja has been one of the more seismically active volcanoes in Iceland. The majority of these events are due to an extensive geothermal area within the caldera and tectonically induced earthquakes to the northeast which are not related to the magma plumbing system. More intriguing are the less numerous deeper earthquakes at 12-24km depth, situated in three distinct areas within the volcanic system. These earthquakes often show a frequency content which is lower than the shallower activity, but they still show strong P and S wave arrivals indicative of brittle failure, despite their location being well below the brittle-ductile boundary, which, in Askja is ~7km bsl. These earthquakes indicate the presence of melt moving or degassing at depth while the volcano is not inflating, as only high strain rates or increased pore fluid pressures would cause brittle fracture in what is normally an aseismic region in the ductile zone. The lower frequency content must be the result of a slower source time function as earthquakes which are both high frequency and low frequency come from the same cluster, thereby discounting a highly attenuating lower crust. To image the plumbing system beneath Askja, local and regional earthquakes have been used as sources to solve for the velocity structure beneath the volcano. Travel-time tables were created using a finite difference technique and the residuals were used to solve simultaneously for both the earthquake locations

  9. Mineralogical and geochemical study of mud volcanoes in north ...

    African Journals Online (AJOL)

    The gulf of Cadiz is one of the most interesting areas to study mud volcanoes and structures related to cold fluid seeps since their discovery in 1999. In this study, we present results from gravity cores collected from Ginsburg and Meknes mud volcanoes and from circular structure located in the gulf of Cadiz (North Atlantic ...

  10. Fuego Volcano eruption (Guatemala, 1974): evidence of a tertiary fragmentation?

    International Nuclear Information System (INIS)

    Brenes-Andre, Jose

    2014-01-01

    Values for mode and dispersion calculated from SFT were analyzed using the SFT (Sequential Fragmentation/Transport) model to Fuego Volcano eruption (Guatemala, 1974). Analysis results have showed that the ideas initially proposed for Irazu, can be applied to Fuego Volcano. Experimental evidence was found corroborating the existence of tertiary fragmentations. (author) [es

  11. 36 CFR 7.25 - Hawaii Volcanoes National Park.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Hawaii Volcanoes National Park. 7.25 Section 7.25 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.25 Hawaii Volcanoes National Park. (a...

  12. Using Google Earth to Study the Basic Characteristics of Volcanoes

    Science.gov (United States)

    Schipper, Stacia; Mattox, Stephen

    2010-01-01

    Landforms, natural hazards, and the change in the Earth over time are common material in state and national standards. Volcanoes exemplify these standards and readily capture the interest and imagination of students. With a minimum of training, students can recognize erupted materials and types of volcanoes; in turn, students can relate these…

  13. Volcano ecology: Disturbance characteristics and assembly of biological communities

    Science.gov (United States)

    Volcanic eruptions are powerful expressions of Earth’s geophysical forces which have shaped and influenced ecological systems since the earliest days of life. The study of the interactions of volcanoes and ecosystems, termed volcano ecology, focuses on the ecological responses of organisms and biolo...

  14. Copahue volcano and its regional magmatic setting

    Science.gov (United States)

    Varekamp, J C; Zareski, J E; Camfield, L M; Todd, Erin

    2016-01-01

    Copahue volcano (Province of Neuquen, Argentina) has produced lavas and strombolian deposits over several 100,000s of years, building a rounded volcano with a 3 km elevation. The products are mainly basaltic andesites, with the 2000–2012 eruptive products the most mafic. The geochemistry of Copahue products is compared with those of the main Andes arc (Llaima, Callaqui, Tolhuaca), the older Caviahue volcano directly east of Copahue, and the back arc volcanics of the Loncopue graben. The Caviahue rocks resemble the main Andes arc suite, whereas the Copahue rocks are characterized by lower Fe and Ti contents and higher incompatible element concentrations. The rocks have negative Nb-Ta anomalies, modest enrichments in radiogenic Sr and Pb isotope ratios and slightly depleted Nd isotope ratios. The combined trace element and isotopic data indicate that Copahue magmas formed in a relatively dry mantle environment, with melting of a subducted sediment residue. The back arc basalts show a wide variation in isotopic composition, have similar water contents as the Copahue magmas and show evidence for a subducted sedimentary component in their source regions. The low 206Pb/204Pb of some backarc lava flows suggests the presence of a second endmember with an EM1 flavor in its source. The overall magma genesis is explained within the context of a subducted slab with sediment that gradually looses water, water-mobile elements, and then switches to sediment melt extracts deeper down in the subduction zone. With the change in element extraction mechanism with depth comes a depletion and fractionation of the subducted complex that is reflected in the isotope and trace element signatures of the products from the main arc to Copahue to the back arc basalts.

  15. Isotopic evolution of Mauna Loa volcano

    International Nuclear Information System (INIS)

    Kurz, M.D.; Kammer, D.P.

    1991-01-01

    In an effort to understand the temporal helium isotopic variations in Mauna Loa volcano, we have measured helium, strontium and lead isotopes in a suite of Mauna Loa lavas that span most of the subaerial eruptive history of the volcano. The lavas range in age from historical flows to Ninole basalt which are thought to be several hundred thousand years old. Most of the samples younger than 30 ka in age (Kau Basalt) are radiocarbon-dated flows, while the samples older than 30 ka are stratigraphically controlled (Kahuku and Ninole Basalt). The data reveal a striking change in the geochemistry of the lavas approximately 10 ka before present. The lavas older than 10 ka are characterized by high 3 He/ 4 He (≅ 16-20 times atmospheric), higher 206 Pb/ 204 Pb (≅ 18.2), and lower 87 Sr/ 86 Sr(≅ 0.70365) ratios than the younger Kau samples (having He, Pb and Sr ratios of approximately 8.5 x atmospheric, 18.1 and 0.70390, respectively). The historical lavas are distinct in having intermediate Sr and Pb isotopic compositions with 3 He/ 4 He ratios similar to the other young Kau basalt (≅ 8.5 x atmospheric). The isotopic variations are on a shorter time scale (100 to 10,000 years) than has previously been observed for Hawaiian volcanoes, and demonstrate the importance of geochronology and stratigraphy to geochemical studies. The data show consistency between all three isotope systems, which suggests that the variations are not related to magma chamber degassing processes, and that helium is not decoupled from the other isotopes. However, the complex temporal evolution suggests that three distinct mantle sources are required to explain the isotopic data. Most of the Mauna Loa isotopic variations could be explained by mixing between a plume type source, similar to Loihi, and an asthenospheric source with helium isotopic composition close to MORB and elevated Sr isotopic values. (orig./WL)

  16. Monte Carlo Volcano Seismic Moment Tensors

    Science.gov (United States)

    Waite, G. P.; Brill, K. A.; Lanza, F.

    2015-12-01

    Inverse modeling of volcano seismic sources can provide insight into the geometry and dynamics of volcanic conduits. But given the logistical challenges of working on an active volcano, seismic networks are typically deficient in spatial and temporal coverage; this potentially leads to large errors in source models. In addition, uncertainties in the centroid location and moment-tensor components, including volumetric components, are difficult to constrain from the linear inversion results, which leads to a poor understanding of the model space. In this study, we employ a nonlinear inversion using a Monte Carlo scheme with the objective of defining robustly resolved elements of model space. The model space is randomized by centroid location and moment tensor eigenvectors. Point sources densely sample the summit area and moment tensors are constrained to a randomly chosen geometry within the inversion; Green's functions for the random moment tensors are all calculated from modeled single forces, making the nonlinear inversion computationally reasonable. We apply this method to very-long-period (VLP) seismic events that accompany minor eruptions at Fuego volcano, Guatemala. The library of single force Green's functions is computed with a 3D finite-difference modeling algorithm through a homogeneous velocity-density model that includes topography, for a 3D grid of nodes, spaced 40 m apart, within the summit region. The homogenous velocity and density model is justified by long wavelength of VLP data. The nonlinear inversion reveals well resolved model features and informs the interpretation through a better understanding of the possible models. This approach can also be used to evaluate possible station geometries in order to optimize networks prior to deployment.

  17. Two magma bodies beneath the summit of Kilauea Volcano unveiled by isotopically distinct melt deliveries from the mantle

    Science.gov (United States)

    Pietruszka, Aaron J.; Heaton, Daniel E.; Marske, Jared P.; Garcia, Michael O.

    2015-01-01

    The summit magma storage reservoir of Kīlauea Volcano is one of the most important components of the magmatic plumbing system of this frequently active basaltic shield-building volcano. Here we use new high-precision Pb isotopic analyses of Kīlauea summit lavas—from 1959 to the active Halema‘uma‘u lava lake—to infer the number, size, and interconnectedness of magma bodies within the volcano's summit reservoir. From 1971 to 1982, the 206Pb/204Pb ratios of the lavas define two separate magma mixing trends that correlate with differences in vent location and/or pre-eruptive magma temperature. These relationships, which contrast with a single magma mixing trend for lavas from 1959 to 1968, indicate that Kīlauea summit eruptions since at least 1971 were supplied from two distinct magma bodies. The locations of these magma bodies are inferred to coincide with two major deformation centers identified by geodetic monitoring of the volcano's summit region: (1) the main locus of the summit reservoir ∼2–4 km below the southern rim of Kīlauea Caldera and (2) a shallower magma body 4 km3 of lava erupted), must therefore be sustained by a nearly continuous supply of new melt from the mantle. The model results show that a minimum of four compositionally distinct, mantle-derived magma batches were delivered to the volcano (at least three directly to the summit reservoir) since 1959. These melt inputs correlate with the initiation of energetic (1959 Kīlauea Iki) and/or sustained (1969–1974 Mauna Ulu, 1983-present Pu‘u ‘Ō‘ō and 2008-present Halema‘uma‘u) eruptions. Thus, Kīlauea's eruptive behavior is partly tied to the delivery of new magma batches from the volcano's source region within the Hawaiian mantle plume.

  18. Volcano morphometry and volume scaling on Venus

    Science.gov (United States)

    Garvin, J. B.; Williams, R. S., Jr.

    1994-01-01

    A broad variety of volcanic edifices have been observed on Venus. They ranged in size from the limits of resolution of the Magellan SAR (i.e., hundreds of meters) to landforms over 500 km in basal diameter. One of the key questions pertaining to volcanism on Venus concerns the volume eruption rate or VER, which is linked to crustal productivity over time. While less than 3 percent of the surface area of Venus is manifested as discrete edifices larger than 50 km in diameter, a substantial component of the total crustal volume of the planet over the past 0.5 Ga is related to isolated volcanoes, which are certainly more easily studied than the relatively diffusely defined plains volcanic flow units. Thus, we have focused our efforts on constraining the volume productivity of major volcanic edifices larger than 100 km in basal diameter. Our approach takes advantage of the topographic data returned by Magellan, as well as our database of morphometric statistics for the 20 best known lava shields of Iceland, plus Mauna Loa of Hawaii. As part of this investigation, we have quantified the detailed morphometry of nearly 50 intermediate to large scale edifices, with particular attention to their shape systematics. We found that a set of venusian edifices which include Maat, Sapas, Tepev, Sif, Gula, a feature at 46 deg S, 215 deg E, as well as the shield-like structure at 10 deg N, 275 deg E are broadly representative of the approx. 400 volcanic landforms larger than 50 km. The cross-sectional shapes of these 7 representative edifices range from flattened cones (i.e., Sif) similar to classic terrestrial lava shields such as Mauna Loa and Skjaldbreidur, to rather dome-like structures which include Maat and Sapas. The majority of these larger volcanoes surveyed as part of our study displayed cross-sectional topographies with paraboloidal shaped, in sharp contrast with the cone-like appearance of most simple terrestrial lava shields. In order to more fully explore the

  19. The deep structure of Axial Volcano

    Science.gov (United States)

    West, Michael Edwin

    The subsurface structure of Axial Volcano, near the intersection of the Juan de Fuca Ridge and the Cobb-Eickelberg seamount chain in the northeast Pacific, is imaged from an active source seismic experiment. At a depth of 2.25 to 3.5 km beneath Axial lies an 8 km x 12 km region of very low seismic velocities that can only be explained by the presence of magma. In the center of this magma storage chamber at 2--3.5 km below sea floor, the crust is at least 10--20% melt. At depths of 4--5 km there is evidence of additional low concentrations of magma (a few percent) over a larger area. In total, 5--11 km3 of magma are stored in the mid-crust beneath Axial. This is more melt than has been positively identified under any basaltic volcano on Earth. It is also far more than the 0.1--0.2 km3 emplaced during the 1998 eruption. The implied residence time in the magma reservoir of a few hundred to a few thousand years agrees with geochemical trends which suggest prolonged storage and mixing of magmas. The large volume of melt bolsters previous observations that Axial provides much of the material to create crust along its 50 km rift zones. A high velocity ring-shaped feature sits above the magma chamber just outside the caldera walls. This feature is believed to be the result of repeated dike injections from the magma body to the surface during the construction of the volcanic edifice. A rapid change in crustal thickness from 8 to 11 km within 15 km of the caldera implies focused delivery of melt from the mantle. The high flux of magma suggests that melting occurs deeper in the mantle than along the nearby ridge. Melt supply to the volcano is not connected to any plumbing system associated with the adjacent segments of the Juan de Fuca Ridge. This suggests that, despite Axial's proximity to the ridge, the Cobb hot spot currently drives the supply of melt to the volcano.

  20. Degassing Processes at Persistently Active Explosive Volcanoes

    Science.gov (United States)

    Smekens, Jean-Francois

    Among volcanic gases, sulfur dioxide (SO2) is by far the most commonly measured. More than a monitoring proxy for volcanic degassing, SO 2 has the potential to alter climate patterns. Persistently active explosive volcanoes are characterized by short explosive bursts, which often occur at periodic intervals numerous times per day, spanning years to decades. SO 2 emissions at those volcanoes are poorly constrained, in large part because the current satellite monitoring techniques are unable to detect or quantify plumes of low concentration in the troposphere. Eruption plumes also often show high concentrations of ash and/or aerosols, which further inhibit the detection methods. In this work I focus on quantifying volcanic gas emissions at persistently active explosive volcanoes and their variations over short timescales (minutes to hours), in order to document their contribution to natural SO2 flux as well as investigate the physical processes that control their behavior. In order to make these measurements, I first develop and assemble a UV ground-based instrument, and validate it against an independently measured source of SO2 at a coal-burning power plant in Arizona. I establish a measurement protocol and demonstrate that the instrument measures SO 2 fluxes with Indonesia), a volcano that has been producing cycles of repeated explosions with periods of minutes to hours for the past several decades. Semeru produces an average of 21-71 tons of SO2 per day, amounting to a yearly output of 8-26 Mt. Using the Semeru data, along with a 1-D transient numerical model of magma ascent, I test the validity of a model in which a viscous plug at the top of the conduit produces cycles of eruption and gas release. I find that it can be a valid hypothesis to explain the observed patterns of degassing at Semeru. Periodic behavior in such a system occurs for a very narrow range of conditions, for which the mass balance between magma flux and open-system gas escape repeatedly

  1. Mud Volcanoes as Exploration Targets on Mars

    Science.gov (United States)

    Allen, Carlton C.; Oehler, Dorothy Z.

    2010-01-01

    Tens of thousands of high-albedo mounds occur across the southern part of the Acidalia impact basin on Mars. These structures have geologic, physical, mineralogic, and morphologic characteristics consistent with an origin from a sedimentary process similar to terrestrial mud volcanism. The potential for mud volcanism in the Northern Plains of Mars has been recognized for some time, with candidate mud volcanoes reported from Utopia, Isidis, northern Borealis, Scandia, and the Chryse-Acidalia region. We have proposed that the profusion of mounds in Acidalia is a consequence of this basin's unique geologic setting as the depocenter for the tune fraction of sediments delivered by the outflow channels from the highlands.

  2. [Haiti, new immigrant community in Chile].

    Science.gov (United States)

    Sánchez P, Katherin; Valderas J, Jaime; Messenger C, Karen; Sánchez G, Carolina; Barrera Q, Francisco

    2018-04-01

    Migration is a growing phenomenon in Latin America influenced by several factors such as economic stability, employment, social welfare, education and health system. Currently Chile has a positive migration flow rate. Particularly, a significant number of Haitian immigrants has been observed du ring the last years, especially after earthquake of 2010. These immigrants present a different cultural background expressed in relevant aspects of living including parenting and healthcare. Knowing the Haitian culture and its health situation is relevant for a better understanding of their health needs. Haitian people come to Chile looking for a cordial reception and willing to find a place with better perspectives of wellbeing in every sense. Immigration represents a major challenge for Chilean health system that must be embraced. Integration efforts in jobs, health, education system and community living should be enhanced to ensure a prosper settlement in our country. A new immigration law is crucial to solving major problems derived from current law created in 1975.

  3. [Mental disorders among immigrants in Chile].

    Science.gov (United States)

    Rojas, Graciela; Fritsch, Rosemarie; Castro, Ariel; Guajardo, Viviana; Torres, Pamela; Díaz, Berta

    2011-10-01

    Chile is receiving immigrant populations coming from other Latin-American countries. To determine the prevalence of Common Mental Disorders (CMD) among immigrants who live in Independencia, a quarter in Santiago, Chile. A cross sectional study was carried out in the primary health care clinic and in the state-funded school of Independencia. A representative sample of 282 adults and 341 children were interviewed. Mental disorders were diagnosed using CIS-R and MINI structured interviews. The interviewed immigrants came mostly from Peru. The prevalence of mental disorders in the adult population was 17.8% and among children, it was 29.3%. The adult immigrants have a lower prevalence of mental disorders than the Chilean population but it increases among children. Barriers of access to health services, that should be solved, were detected.

  4. Mud Volcanoes of Trinidad as Astrobiological Analogs for Martian Environments

    Directory of Open Access Journals (Sweden)

    Riad Hosein

    2014-10-01

    Full Text Available Eleven onshore mud volcanoes in the southern region of Trinidad have been studied as analog habitats for possible microbial life on Mars. The profiles of the 11 mud volcanoes are presented in terms of their physical, chemical, mineralogical, and soil properties. The mud volcanoes sampled all emitted methane gas consistently at 3% volume. The average pH for the mud volcanic soil was 7.98. The average Cation Exchange Capacity (CEC was found to be 2.16 kg/mol, and the average Percentage Water Content was 34.5%. Samples from three of the volcanoes, (i Digity; (ii Piparo and (iii Devil’s Woodyard were used to culture bacterial colonies under anaerobic conditions indicating possible presence of methanogenic microorganisms. The Trinidad mud volcanoes can serve as analogs for the Martian environment due to similar geological features found extensively on Mars in Acidalia Planitia and the Arabia Terra region.

  5. Measurements of radon and chemical elements: Popocatepetl volcano

    International Nuclear Information System (INIS)

    Pena, P.; Segovia, N.; Lopez, B.; Reyes, A.V.; Armienta, M.A.; Valdes, C.; Mena, M.; Seidel, J.L.; Monnin, M.

    2002-01-01

    The Popocatepetl volcano is a higher risk volcano located at 60 Km from Mexico City. Radon measurements on soil in two fixed seasons located in the north slope of volcano were carried out. Moreover the radon content, major chemical elements and tracks in water samples of three springs was studied. The radon of soil was determined with solid detectors of nuclear tracks (DSTN). The radon in subterranean water was evaluated through the liquid scintillation method and it was corroborated with an Alpha Guard equipment. The major chemical elements were determined with conventional chemical methods and the track elements were measured using an Icp-Ms equipment. The radon on soil levels were lower, indicating a moderate diffusion of the gas across the slope of the volcano. The radon in subterranean water shown few changes in relation with the active scene of the volcano. The major chemical elements and tracks showed a stable behavior during the sampling period. (Author)

  6. Mud Volcanoes of Trinidad as Astrobiological Analogs for Martian Environments

    Science.gov (United States)

    Hosein, Riad; Haque, Shirin; Beckles, Denise M.

    2014-01-01

    Eleven onshore mud volcanoes in the southern region of Trinidad have been studied as analog habitats for possible microbial life on Mars. The profiles of the 11 mud volcanoes are presented in terms of their physical, chemical, mineralogical, and soil properties. The mud volcanoes sampled all emitted methane gas consistently at 3% volume. The average pH for the mud volcanic soil was 7.98. The average Cation Exchange Capacity (CEC) was found to be 2.16 kg/mol, and the average Percentage Water Content was 34.5%. Samples from three of the volcanoes, (i) Digity; (ii) Piparo and (iii) Devil’s Woodyard were used to culture bacterial colonies under anaerobic conditions indicating possible presence of methanogenic microorganisms. The Trinidad mud volcanoes can serve as analogs for the Martian environment due to similar geological features found extensively on Mars in Acidalia Planitia and the Arabia Terra region. PMID:25370529

  7. Tsunamis generated by eruptions from mount st. Augustine volcano, alaska.

    Science.gov (United States)

    Kienle, J; Kowalik, Z; Murty, T S

    1987-06-12

    During an eruption of the Alaskan volcano Mount St. Augustine in the spring of 1986, there was concern about the possibility that a tsunami might be generated by the collapse of a portion of the volcano into the shallow water of Cook Inlet. A similar edifice collapse of the volcano and ensuing sea wave occurred during an eruption in 1883. Other sea waves resulting in great loss of life and property have been generated by the eruption of coastal volcanos around the world. Although Mount St. Augustine remained intact during this eruptive cycle, a possible recurrence of the 1883 events spurred a numerical simulation of the 1883 sea wave. This simulation, which yielded a forecast of potential wave heights and travel times, was based on a method that could be applied generally to other coastal volcanos.

  8. Mud volcanoes of trinidad as astrobiological analogs for martian environments.

    Science.gov (United States)

    Hosein, Riad; Haque, Shirin; Beckles, Denise M

    2014-10-13

    Eleven onshore mud volcanoes in the southern region of Trinidad have been studied as analog habitats for possible microbial life on Mars. The profiles of the 11 mud volcanoes are presented in terms of their physical, chemical, mineralogical, and soil properties. The mud volcanoes sampled all emitted methane gas consistently at 3% volume. The average pH for the mud volcanic soil was 7.98. The average Cation Exchange Capacity (CEC) was found to be 2.16 kg/mol, and the average Percentage Water Content was 34.5%. Samples from three of the volcanoes, (i) Digity; (ii) Piparo and (iii) Devil's Woodyard were used to culture bacterial colonies under anaerobic conditions indicating possible presence of methanogenic microorganisms. The Trinidad mud volcanoes can serve as analogs for the Martian environment due to similar geological features found extensively on Mars in Acidalia Planitia and the Arabia Terra region.

  9. Utilizing NASA Earth Observations to Model Volcanic Hazard Risk Levels in Areas Surrounding the Copahue Volcano in the Andes Mountains

    Science.gov (United States)

    Keith, A. M.; Weigel, A. M.; Rivas, J.

    2014-12-01

    Copahue is a stratovolcano located along the rim of the Caviahue Caldera near the Chile-Argentina border in the Andes Mountain Range. There are several small towns located in proximity of the volcano with the two largest being Banos Copahue and Caviahue. During its eruptive history, it has produced numerous lava flows, pyroclastic flows, ash deposits, and lahars. This isolated region has steep topography and little vegetation, rendering it poorly monitored. The need to model volcanic hazard risk has been reinforced by recent volcanic activity that intermittently released several ash plumes from December 2012 through May 2013. Exposure to volcanic ash is currently the main threat for the surrounding populations as the volcano becomes more active. The goal of this project was to study Copahue and determine areas that have the highest potential of being affected in the event of an eruption. Remote sensing techniques were used to examine and identify volcanic activity and areas vulnerable to experiencing volcanic hazards including volcanic ash, SO2 gas, lava flow, pyroclastic density currents and lahars. Landsat 7 Enhanced Thematic Mapper Plus (ETM+), Landsat 8 Operational Land Imager (OLI), EO-1 Advanced Land Imager (ALI), Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Shuttle Radar Topography Mission (SRTM), ISS ISERV Pathfinder, and Aura Ozone Monitoring Instrument (OMI) products were used to analyze volcanic hazards. These datasets were used to create a historic lava flow map of the Copahue volcano by identifying historic lava flows, tephra, and lahars both visually and spectrally. Additionally, a volcanic risk and hazard map for the surrounding area was created by modeling the possible extent of ash fallout, lahars, lava flow, and pyroclastic density currents (PDC) for future eruptions. These model results were then used to identify areas that should be prioritized for disaster relief and evacuation orders.

  10. Characteristics and management of the 2006-2008 volcanic crisis at the Ubinas volcano (Peru)

    Science.gov (United States)

    Rivera, Marco; Thouret, Jean-Claude; Mariño, Jersy; Berolatti, Rossemary; Fuentes, José

    2010-12-01

    Ubinas volcano is located 75 km East of Arequipa and ca. 5000 people are living within 12 km from the summit. This composite cone is considered the most active volcano in southern Peru owing to its 24 low to moderate magnitude (VEI 1-3) eruptions in the past 500 years. The onset of the most recent eruptive episode occurred on 27 March 2006, following 8 months of heightened fumarolic activity. Vulcanian explosions occurred between 14 April 2006 and September 2007, at a time ejecting blocks up to 40 cm in diameter to distances of 2 km. Ash columns commonly rose to 3.5 km above the caldera rim and dispersed fine ash and aerosols to distances of 80 km between April 2006 and April 2007. Until April 2007, the total volume of ash was estimated at 0.004 km 3, suggesting that the volume of fresh magma was small. Ash fallout has affected residents, livestock, water supplies, and crop cultivation within an area of ca. 100 km 2 around the volcano. Continuous degassing and intermittent mild vulcanian explosions lasted until the end of 2008. Shortly after the initial explosions on mid April 2006 that spread ash fallout within 7 km of the volcano, an integrated Scientific Committee including three Peruvian institutes affiliated to the Regional Committee of Civil Defense for Moquegua, aided by members of the international cooperation, worked together to: i) elaborate and publish volcanic hazard maps; ii) inform and educate the population; and iii) advise regional authorities in regard to the management of the volcanic crisis and the preparation of contingency plans. Although the 2006-2008 volcanic crisis has been moderate, its management has been a difficult task even though less than 5000 people now live around the Ubinas volcano. However, the successful management has provided experience and skills to the scientific community. This volcanic crisis was not the first one that Peru has experienced but the 2006-2008 experience is the first long-lasting crisis that the Peruvian civil

  11. UPDATE: MAJOR EARTHQUAKE IN CHILE (II) | CTIO

    Science.gov (United States)

    Preserving the Dark Skies La Oficina de Protección de la Calidad del Cielo del Norte de Chile - OPCC Light el acceso a ambas cumbres. Los tanques de agua sobre Tololo fueron dañados causando una fuga importante, y las líneas de control se cortaron poniendo fuera de operación las bombas de agua. Las

  12. The Neutral Interest Rate: Estimates for Chile

    OpenAIRE

    Rodrigo Fuentes S; Fabián Gredig U.

    2008-01-01

    To estimate the neutral real interest rate for Chile, we use a variety of methods that can be classified into three categories: those derived from economic theory, the neutral rate implicit in financial assets, and statistical procedures using macroeconomic data. We conclude that the neutral rate is not constant over time, but it is closely related with—though not equivalent to—the potential GDP growth rate. The application of the different methods yields fairly similar results. The neutral r...

  13. Chile's pipelines - who's out in the cold?

    International Nuclear Information System (INIS)

    Bellhouse, G.

    1998-01-01

    There is a battle on in Northern Chile to supply the region with gas and electricity. Two pipelines and a transmission line are being built, but there is insufficient demand to merit the construction of all of these projects. It is widely believed that the first pipeline to be finished will be the overall winner, but the situation is not that simple. A more sensible conclusion could be the merger of the two pipeline projects, rationalising supply of gas to the region. (Author)

  14. The current situation for gastric cancer in Chile.

    Science.gov (United States)

    Caglevic, Christian; Silva, Shirley; Mahave, Mauricio; Rolfo, Christian; Gallardo, Jorge

    2016-01-01

    Gastric cancer is a neoplasm with a high incidence and mortality rate in Chile where more than 3000 people die every year from this type of cancer. This study shows the clinical and epidemiological considerations of this disease, information about translational research on this pathology in Chile, the contribution of Chilean doctors to the development of gastric cancer management awareness and the general situation of gastric cancer in Chile.

  15. Chile: Civil-Military Relations and Democratic Consolidation

    Science.gov (United States)

    1998-12-01

    Publishers, 1992), 41. 26 Javier Martinez and Alvaro Diaz , Chile The Great Transformation (Harrisonburg, Virginia: The Brookings Institution, 1996...the world economy, by means of technological advancements, makes it necessary to reduce 32 Javier Martinez and Alvaro Diaz , Chile the Great...disapproves the executive’s budget. There is no 60 Alicia Frohman, "Chile: External Actors and the Transition to Democracy," in Beyond Sovereignty

  16. Translating Volcano Hazards Research in the Cascades Into Community Preparedness

    Science.gov (United States)

    Ewert, J. W.; Driedger, C. L.

    2015-12-01

    Research by the science community into volcanic histories and physical processes at Cascade volcanoes in the states of Washington, Oregon, and California has been ongoing for over a century. Eruptions in the 20th century at Lassen Peak and Mount St. Helen demonstrated the active nature of Cascade volcanoes; the 1980 eruption of Mount St. Helens was a defining moment in modern volcanology. The first modern volcano hazards assessments were produced by the USGS for some Cascade volcanoes in the 1960s. A rich scientific literature exists, much of which addresses hazards at these active volcanoes. That said community awareness, planning, and preparation for eruptions generally do not occur as a result of a hazard analyses published in scientific papers, but by direct communication with scientists. Relative to other natural hazards, volcanic eruptions (or large earthquakes, or tsunami) are outside common experience, and the public and many public officials are often surprised to learn of the impacts volcanic eruptions could have on their communities. In the 1980s, the USGS recognized that effective hazard communication and preparedness is a multi-faceted, long-term undertaking and began working with federal, state, and local stakeholders to build awareness and foster community action about volcano hazards. Activities included forming volcano-specific workgroups to develop coordination plans for volcano emergencies; a concerted public outreach campaign; curriculum development and teacher training; technical training for emergency managers and first responders; and development of hazard information that is accessible to non-specialists. Outcomes include broader ownership of volcano hazards as evidenced by bi-national exchanges of emergency managers, community planners, and first responders; development by stakeholders of websites focused on volcano hazards mitigation; and execution of table-top and functional exercises, including evacuation drills by local communities.

  17. Adding the human dimension to drought: an example from Chile

    Science.gov (United States)

    Rangecroft, Sally; Van Loon, Anne; Maureira, Héctor; Rojas, Pablo; Alejandro Gutiérrez Valdés, Sergio; Verbist, Koen

    2016-04-01

    Drought and water scarcity are important hazards and can lead to severe socio-economic impacts in many regions of the world. Given the interlinked interactions and feedbacks of hydrological droughts and their impacts and management, we need tools to evaluate these complexities and effects on the availability of water resources. Here we use a real-world case study of the Huasco basin (Northern Chile) in which we quantify the influence of human activities on hydrological drought signals. In this arid region, Andean snowmelt provides water essential for users, with agriculture acting as the main water consumer (85% of total). An increasing water demand from different water sectors (agriculture, mining, and domestic water usage) has increased pressure on available water and its management. Consequently, the Santa Juana dam was built by 1995 to increase irrigation security for downstream users, and recent management and restrictions have been established with the objective to limit impacts of hydrological droughts across the basin. The feedbacks between water availability and water management are explored for this water stressed region in Chile. Hydro-meteorological (e.g. precipitation, temperature, streamflow, reservoir levels) variables have been analysed to assess trends and drought patterns. Data over the past three decades has indicated a decrease in surface water supply, with the basin entering a situation of water scarcity during the recent multiyear drought (2007 - to-date), partly caused by meteorological drought and partly by abstraction. During this period, water supply failed to meet the demands of water users, resulting in the implementation of water restrictions. As well as the necessary continuous hydro-meteorological data, here we used information on human water users and scenario modeling, allowing for the analysis and quantification of feedbacks. This work highlights the importance of local knowledge, especially in understanding water laws, rights

  18. Radiological protection in interventional cardiology in Chile

    International Nuclear Information System (INIS)

    Ramirez, A.; Leyton, F.A.; Farias, E.; Silva, A.M.; Vano, E.; Oyarzun, C.; Gamarra, J.; Ortiz, P.

    2001-01-01

    In September 2000, an expert mission was assigned to Chile, under the regional project named 'International BBS in Medical Practices Radiation Protection and Quality Assurance In Interventional Radiology' (ARCAL XLIX). The objective of the mission was to evaluate the level of radiation protection (RP) and safety in interventional cardiology ( IC ) installations. A team of local cardiologists, medical physicists and technologists was created for this purpose and during one week, several cardiology laboratories were evaluated and some basic quality controls (QC) were carried out. A basic pilot training course in radiation protection was imparted at the Hospital of the University of Chile in Santiago de Chile and some of the key objectives for a future national quality assurance programme were presented during the national congress of IC. In addition, a national survey on radiation protection aspects was circulated and its results evaluated. These activities enabled the local team to become familiar with the methodology of assessment of the level of protection and the organization of a programme, which was illustrated with the examples of similar European programmes. As result of these actions, several proposals were made to both the local authorities and the IAEA. The most important were: a) to initiate a basic QC programme, b) to organize a training in RP for cardiologists in order to formalize their accreditation, c) to improve personal occupational dosimetry, d) to initiate a programme of patient dosimetry, e) to optimize the technical and clinical protocols, f) to create a national registry of incidents with skin injuries. (author)

  19. Registro nuevo de Amphipyrinae en Chile A new record of Amphipyrinae from Chile

    Directory of Open Access Journals (Sweden)

    Tania S. Olivares

    2006-12-01

    Full Text Available Se registra por primera vez en Chile la especie Agrotisia subhyalina Hampson, entre las latitudes 18° 29' S 70° 20' O hasta 29° 54' S 71° 16' O (I-IV regiones en Chile. Se redescriben los genitales del macho y de la hembra y se presentan algunos aspectos taxonómicos de la especie.The species Agrotisia subhyalina Hampson is recorded for the first time from Chile (18° 29' S 70° 20' W to 29° 54' S 71° 16' W, I to IV Chilean regions. Redescriptions of male and female are presented, along with some taxonomic aspects of the species.

  20. Continuous auditing & continuous monitoring : Continuous value?

    NARCIS (Netherlands)

    van Hillo, Rutger; Weigand, Hans; Espana, S; Ralyte, J; Souveyet, C

    2016-01-01

    Advancements in information technology, new laws and regulations and rapidly changing business conditions have led to a need for more timely and ongoing assurance with effectively working controls. Continuous Auditing (CA) and Continuous Monitoring (CM) technologies have made this possible by

  1. The 2011-2012 eruption of Cordón Caulle volcano (Southern Andes): Evolution, crisis management and current hazards

    Science.gov (United States)

    Silva Parejas, C.; Lara, L. E.; Bertin, D.; Amigo, A.; Orozco, G.

    2012-04-01

    A new kind of integrated approach was for first time achieved during the eruptive crisis of Cordón Caulle volcano (Southern Andes, 40.59°S, 72.12°W) in Chile. The monitoring network of SERNAGEOMIN around the volcano detected the increasing precursory seismicity, alerting the imminence of an eruption about 5 hours before its onset, on June 4, 2011. In addition, SERNAGEOMIN generated daily forecasts of tephra dispersal and fall (ASHFALL advection-diffusion model), and prepared simulations of areas affected by the possible occurrence of lahars and pyroclastic flows. Models were improved with observed effects on the field and satellite imagery, resulting in a good correlation. The information was timely supplied to the authorities as well as recommendations in order to better precise the vulnerable areas. Eruption has initially occurred from a couple of overlapped cones located along the eastern fault scarp of the Pleistocene-Holocene extensional graben of Cordón Caulle. Eruptive products have virtually the same bulk composition as those of the historical 1921 and 1960 eruptions, corresponding to phenocryst-poor rhyodacites (67-70 % SiO2). During the first eruptive stage, a ca. 15-km strong Plinian column lasting 27 hours emitted 0.2-0.4 km3 of magma (DRE). Thick tephra deposits have been accumulated in Chile and Argentina, whereas fine particles and aerosols dispersion disrupted air navigation across the Southern Hemisphere. The second ongoing eruptive stage, which started in mid-June, has been characterized by lava emission already covering a total area comparable to the 1960 lava flows with a total estimated volume Argentina until the end of the year. Main current hazards at Cordón Caulle volcano are fine tephra fallout, secondary lahars, minor explosions and lava flow front collapse. Even if this case can be considered successful from the point of view of eruption forecast and hazard assessment, a new protocol of volcanic alerts has been recently signed

  2. Volcano-ice interactions on Mars

    International Nuclear Information System (INIS)

    Allen, C.C.

    1979-01-01

    Central volcanic eruptions beneath terrestrial glaciers have built steep-sided, flat-topped mountains composed of pillow lava, glassy tuff, capping flows, and cones of basalt. Subglacial fissure eruptions produced ridges of similar compostion. In some places the products from a number of subglacial vents have combined to form widespread deposits. The morphologies of these subglacial volcanoes are distinctive enough to allow their recognition at the resolutions characteristic of Viking orbiter imagery. Analogs to terrestrial subglacial volcanoes have been identified on the northern plains and near the south polar cap of Mars. The polar feature provides probable evidence of volcanic eruptions beneath polar ice. A mixed unit of rock and ice is postulated to have overlain portions of the northern plains, with eruptions into this ground ice having produced mountains and ridges analogous to those in Iceland. Subsequent breakdown of this unit due to ice melting revealed the volcanic features. Estimated heights of these landforms indicate that the ice-rich unit once ranged from approximately 100 to 1200 m thick

  3. Rapid response of a hydrologic system to volcanic activity: Masaya volcano, Nicaragua

    Science.gov (United States)

    Pearson, S.C.P.; Connor, C.B.; Sanford, W.E.

    2008-01-01

    Hydrologic systems change in response to volcanic activity, and in turn may be sensitive indicators of volcanic activity. Here we investigate the coupled nature of magmatic and hydrologic systems using continuous multichannel time series of soil temperature collected on the flanks of Masaya volcano, Nicaragua, one of the most active volcanoes in Central America. The soil temperatures were measured in a low-temperature fumarole field located 3.5 km down the flanks of the volcano. Analysis of these time series reveals that they respond extremely rapidly, on a time scale of minutes, to changes in volcanic activity also manifested at the summit vent. These rapid temperature changes are caused by increased flow of water vapor through flank fumaroles during volcanism. The soil temperature response, ~5 °C, is repetitive and complex, with as many as 13 pulses during a single volcanic episode. Analysis of the frequency spectrum of these temperature time series shows that these anomalies are characterized by broad frequency content during volcanic activity. They are thus easily distinguished from seasonal trends, diurnal variations, or individual rainfall events, which triggered rapid transient increases in temperature during 5% of events. We suggest that the mechanism responsible for the distinctive temperature signals is rapid change in pore pressure in response to magmatism, a response that can be enhanced by meteoric water infiltration. Monitoring of distal fumaroles can therefore provide insight into coupled volcanic-hydrologic-meteorologic systems, and has potential as an inexpensive monitoring tool.

  4. Monitoring changes in seismic velocity related to an ongoing rapid inflation event at Okmok volcano, Alaska

    Science.gov (United States)

    Bennington, Ninfa; Haney, Matt; De Angelis, Silvio; Thurber, Clifford; Freymueller, Jeff

    2015-01-01

    Okmok is one of the most active volcanoes in the Aleutian Arc. In an effort to improve our ability to detect precursory activity leading to eruption at Okmok, we monitor a recent, and possibly ongoing, GPS-inferred rapid inflation event at the volcano using ambient noise interferometry (ANI). Applying this method, we identify changes in seismic velocity outside of Okmok’s caldera, which are related to the hydrologic cycle. Within the caldera, we observe decreases in seismic velocity that are associated with the GPS-inferred rapid inflation event. We also determine temporal changes in waveform decorrelation and show a continual increase in decorrelation rate over the time associated with the rapid inflation event. Themagnitude of relative velocity decreases and decorrelation rate increases are comparable to previous studies at Piton de la Fournaise that associate such changes with increased production of volatiles and/ormagmatic intrusion within the magma reservoir and associated opening of fractures and/or fissures. Notably, the largest decrease in relative velocity occurs along the intrastation path passing nearest to the center of the caldera. This observation, along with equal amplitude relative velocity decreases revealed via analysis of intracaldera autocorrelations, suggests that the inflation sourcemay be located approximately within the center of the caldera and represent recharge of shallow magma storage in this location. Importantly, there is a relative absence of seismicity associated with this and previous rapid inflation events at Okmok. Thus, these ANI results are the first seismic evidence of such rapid inflation at the volcano.

  5. Crustal movements due to Iceland's shrinking ice caps mimic magma inflow signal at Katla volcano.

    Science.gov (United States)

    Spaans, Karsten; Hreinsdóttir, Sigrún; Hooper, Andrew; Ófeigsson, Benedikt Gunnar

    2015-05-20

    Many volcanic systems around the world are located beneath, or in close proximity to, ice caps. Mass change of these ice caps causes surface movements, which are typically neglected when interpreting surface deformation measurements around these volcanoes. These movements can however be significant, and may closely resemble movements due to magma accumulation. Here we show such an example, from Katla volcano, Iceland. Horizontal movements observed by GPS on the flank of Katla have led to the inference of significant inflow of magma into a chamber beneath the caldera, starting in 2000, and continuing over several years. We use satellite radar interferometry and GPS data to show that between 2001 and 2010, the horizontal movements seen on the flank can be explained by the response to the long term shrinking of ice caps, and that erratic movements seen at stations within the caldera are also not likely to signify magma inflow. It is important that interpretations of geodetic measurements at volcanoes in glaciated areas consider the effect of ice mass change, and previous studies should be carefully reevaluated.

  6. Operational tracking of lava lake surface motion at Kīlauea Volcano, Hawai‘i

    Science.gov (United States)

    Patrick, Matthew R.; Orr, Tim R.

    2018-03-08

    Surface motion is an important component of lava lake behavior, but previous studies of lake motion have been focused on short time intervals. In this study, we implement the first continuous, real-time operational routine for tracking lava lake surface motion, applying the technique to the persistent lava lake in Halema‘uma‘u Crater at the summit of Kīlauea Volcano, Hawai‘i. We measure lake motion by using images from a fixed thermal camera positioned on the crater rim, transmitting images to the Hawaiian Volcano Observatory (HVO) in real time. We use an existing optical flow toolbox in Matlab to calculate motion vectors, and we track the position of lava upwelling in the lake, as well as the intensity of spattering on the lake surface. Over the past 2 years, real-time tracking of lava lake surface motion at Halema‘uma‘u has been an important part of monitoring the lake’s activity, serving as another valuable tool in the volcano monitoring suite at HVO.

  7. [Who finances medical research in Chile?].

    Science.gov (United States)

    Reyes, H; Kauffmann, R; Goic, A

    1995-10-01

    To identify those institutions granting medical research in Chile, every issue of Revista Médica de Chile published between 1987 and 1994 was reviewed, under the assumption that a vast majority (over 70%) of papers released by Chilean authors in topics of internal medicine and related subspecialties would have been submitted for publication in this journal. This assumption was based in the solid prestige of Revista Médica de Chile among Chilean physicians and investigators: it is one of the oldest medical journals in the world (founded in 1872) and its inclusion in the most important international indexes (e.g. Index Medicus, Current Contents) qualifies it in the "mainstream literature". Papers classified as "Original Articles", "Clinical Experiences", "Review Articles", "Public Health", "Case Reports", "Clinical Laboratory", "Special Articles" and "Medical Education" were screened for acknowledgment of financial support beyond the resources needed for routine clinical work. Among 1,528 manuscripts published, 344 were "Original Articles" and 61.3% of them acknowledged special financial support. Five hundred and one manuscripts were "Clinical Experiences" and 21.5% of them received special financial support; similar proportions were detected in "Review Articles" and "Public Health" topics. The institution ranked as providing support most often was the "Fondo Nacional de Ciencias y Tecnología" (FONDECYT), a governmental fund that assigns resources to research in all areas of science and technology through a peer-reviewed nationwide annual contest. FONDECYT was identified as provider of financial support to 45.2% of the "Original Articles" and "Clinical Experiences"; Chilean universities were mentioned by 33.6% and other entities (including pharmaceutical companies, other national and foreign organizations) by 23.1%. The University of Chile was the main Chilean university mentioned in the acknowledgments. The proportion of papers receiving special financial support

  8. Local Perception of Drought Impacts in a Changing Climate: The Mega-Drought in Central Chile

    Directory of Open Access Journals (Sweden)

    Paulina Aldunce

    2017-11-01

    Full Text Available Droughts are a recurrent and complex natural hazard whose frequency and magnitude are expected to increase with climate change. Despite the advances in responding and adapting to droughts (with the development of new policies, for example, droughts continue to cause serious impacts and suffering. Developing well-targeted public policies requires further research on adaptation. Specifically, understanding the public perception of drought can help to identify drivers of and barriers to adaptation and options. This research seeks to understand the public perception of drought in central Chile in order to inform adaptation-related policies and decision-making processes. This study focused on the Mega-drought, which was a protracted dry spell afflicting central Chile since 2010.

  9. Chile shadow report to the United Nations sheds light on women's rights.

    Science.gov (United States)

    Farmer, A

    1999-07-01

    Three Chilean women's rights organizations and CRLP presented a Shadow Report to the UN Committee on the Elimination of All Forms of Discrimination Against Women (CEDAW). The 25-page Shadow Report indicates in summary the disappointment of the Chilean women in their government. Although Chile has emerged from its history of military dictatorship and is taking its first steps toward returning to a democratic-style of government, the military and the Catholic Church still exert a very strong influence, especially when it comes to policy making. Chilean people especially women, continue to be tyrannized by repressive attitudes, laws, and policies. This tyrannization is exemplified by the rampant discrimination against women in the prisons and the punishment of those undergoing illegal abortions. In short, women have no rights in Chile, and the government has not done enough to eliminate discrimination against them.

  10. Three-dimensional stochastic adjustment of volcano geodetic network in Arenal volcano, Costa Rica

    Science.gov (United States)

    Muller, C.; van der Laat, R.; Cattin, P.-H.; Del Potro, R.

    2009-04-01

    Volcano geodetic networks are a key instrument to understanding magmatic processes and, thus, forecasting potentially hazardous activity. These networks are extensively used on volcanoes worldwide and generally comprise a number of different traditional and modern geodetic surveying techniques such as levelling, distances, triangulation and GNSS. However, in most cases, data from the different methodologies are surveyed, adjusted and analysed independently. Experience shows that the problem with this procedure is the mismatch between the excellent correlation of position values within a single technique and the low cross-correlation of such values within different techniques or when the same network is surveyed shortly after using the same technique. Moreover one different independent network for each geodetic surveying technique strongly increase logistics and thus the cost of each measurement campaign. It is therefore important to develop geodetic networks which combine the different geodetic surveying technique, and to adjust geodetic data together in order to better quantify the uncertainties associated to the measured displacements. In order to overcome the lack of inter-methodology data integration, the Geomatic Institute of the University of Applied Sciences of Western Switzerland (HEIG-VD) has developed a methodology which uses a 3D stochastic adjustment software of redundant geodetic networks, TRINET+. The methodology consists of using each geodetic measurement technique for its strengths relative to other methodologies. Also, the combination of the measurements in a single network allows more cost-effective surveying. The geodetic data are thereafter adjusted and analysed in the same referential frame. The adjustment methodology is based on the least mean square method and links the data with the geometry. Trinet+ also allows to run a priori simulations of the network, hence testing the quality and resolution to be expected for a determined network even

  11. Systematics of Alkali Metals in Pore Fluids from Serpentinite Mud Volcanoes: IODP Expedition 366

    Science.gov (United States)

    Wheat, C. G.; Ryan, J.; Menzies, C. D.; Price, R. E.; Sissmann, O.

    2017-12-01

    IODP Expedition 366 focused, in part, on the study of geo­chemical cycling, matrix alteration, material and fluid transport, and deep biosphere processes within the subduction channel in the Mariana forearc. This was accomplished through integrated sampling of summit and flank regions of three active serpentinite mud volcanoes (Yinazao (Blue Moon), Asùt Tesoro (Big Blue), and Fantangisña (Celestial) Seamounts). These edifices present a transect of depths to the Pacific Plate, allowing one to characterize thermal, pressure and compositional effects on processes that are associated with the formation of serpentinite mud volcanoes and continued activity below and within them. Previous coring on ODP Legs 125 and 195 at two other serpentinite mud volcanoes (Conical and South Chamorro Seamounts) and piston, gravity, and push cores from several other Mariana serpentinite mud volcanoes add to this transect of sites where deep-sourced material is discharged at the seafloor. Pore waters (149 samples) were squeezed from serpentinite materials to determine the composition of deep-sourced fluid and to assess the character, extent, and effect of diagenetic reactions and mixing with seawater on the flanks of the seamounts as the serpentinite matrix weathers. In addition two Water Sampler Temperature Tool (WSTP) fluid samples were collected within two of the cased boreholes, each with at least 30 m of screened casing that allows formations fluids to discharge into the borehole. Shipboard results for Na and K record marked seamount-to-seamount differences in upwelling summit fluids, and complex systematics in fluids obtained from flank sites. Here we report new shore-based Rb and Cs measurements, two elements that have been used to constrain the temperature of the deep-sourced fluid. Data are consistent with earlier coring and drilling expeditions, resulting in systematic changes with depth (and by inference temperature) to the subduction channel.

  12. Episodic inflation and complex surface deformation of Akutan volcano, Alaska revealed from GPS time-series

    Science.gov (United States)

    DeGrandpre, Kimberly; Wang, Teng; Lu, Zhong; Freymueller, Jeffrey T.

    2017-11-01

    Akutan is one of the most active volcanoes in the Aleutian island arc. Studies involving seismic, GPS, and InSAR data have observed activity and deformation on the island since 1996. In this study we inverted measurements of volcanic deformation, observed using three components of motions at 12 continuous GPS sites to define magma source parameters using Mogi point source, Okada dislocation, and Yang spheroid and ellipsoid models. In order to analyze the evolution of this magma source we split the GPS data into five consecutive time periods, and one period that incorporates all available data. These time periods were designed around two inflation events in 2008 and 2014, when a sudden and significant increase in vertical velocity was observed. Inversion of these time periods independently allowed us to create a magma volume time-series that is related to the physical migration of magma defined by the estimated source parameters. The best fit model parameters resulting from these inversions describes magma storage in the form of an oblate spheroid centered on the northeastern rim of the caldera of Akutan volcano, extending from a depth of 7 km to 8 km, with a length of 3.5 km, a strike of N165°E, and a dip of 63° from the horizontal to the southwest. Our model results were compared with seismic studies and found to support previous interpretations of episodic inflation beneath Akutan volcano with complicated magma storage at intermediate depths. The inflation event observed in 2008 was estimated to be the result of an injection of magma of 0.08 km3 that was followed in 2014 by an additional increase in volume of 0.06 km3. No periods of deflation were observed in the GPS data after these events, and we believe the total volume of magma accumulated in this region, 0.2 km3, remains in a shallow storage system beneath Akutan Volcano.

  13. Standardisation of the USGS Volcano Alert Level System (VALS): analysis and ramifications

    Science.gov (United States)

    Fearnley, C. J.; McGuire, W. J.; Davies, G.; Twigg, J.

    2012-11-01

    The standardisation of volcano early warning systems (VEWS) and volcano alert level systems (VALS) is becoming increasingly common at both the national and international level, most notably following UN endorsement of the development of globally comprehensive early warning systems. Yet, the impact on its effectiveness, of standardising an early warning system (EWS), in particular for volcanic hazards, remains largely unknown and little studied. This paper examines this and related issues through evaluation of the emergence and implementation, in 2006, of a standardised United States Geological Survey (USGS) VALS. Under this upper-management directive, all locally developed alert level systems or practices at individual volcano observatories were replaced with a common standard. Research conducted at five USGS-managed volcano observatories in Alaska, Cascades, Hawaii, Long Valley and Yellowstone explores the benefits and limitations this standardisation has brought to each observatory. The study concludes (1) that the process of standardisation was predominantly triggered and shaped by social, political, and economic factors, rather than in response to scientific needs specific to each volcanic region; and (2) that standardisation is difficult to implement for three main reasons: first, the diversity and uncertain nature of volcanic hazards at different temporal and spatial scales require specific VEWS to be developed to address this and to accommodate associated stakeholder needs. Second, the plural social contexts within which each VALS is embedded present challenges in relation to its applicability and responsiveness to local knowledge and context. Third, the contingencies of local institutional dynamics may hamper the ability of a standardised VALS to effectively communicate a warning. Notwithstanding these caveats, the concept of VALS standardisation clearly has continuing support. As a consequence, rather than advocating further commonality of a standardised

  14. Catastrophic precipitation-triggered lahar at Casita volcano, Nicaragua: Occurrence, bulking and transformation

    Science.gov (United States)

    Scott, K.M.; Vallance, J.W.; Kerle, N.; Macias, J.L.; Strauch, W.; Devoli, G.

    2005-01-01

    A catastrophic lahar began on 30 October 1998, as hurricane precipitation triggered a small flank collapse of Casita volcano, a complex and probably dormant stratovolcano. The initial rockslide-debris avalanche evolved on the flank to yield a watery debris flood with a sediment concentration less than 60 per cent by volume at the base of the volcano. Within 2-5 km, however, the watery flow entrained (bulked) enough sediment to transform entirely to a debris flow. The debris flow, 6 km downstream and 1??2 km wide and 3 to 6 m deep, killed 2500 people, nearly the entire populations of the communities of El Porvenir and Rolando Rodriguez. These 'new towns' were developed in a prehistoric lahar pathway: at least three flows of similar size since 8330 14C years BP are documented by stratigraphy in the same 30-degree sector. Travel time between perception of the flow and destruction of the towns was only 2??5-3??0 minutes. The evolution of the flow wave occurred with hydraulic continuity and without pause or any extraordinary addition of water. The precipitation trigger of the Casita lahar emphasizes the nee d, in volcano hazard assessments, for including the potential for non-eruption-related collapse lahars with the more predictable potential of their syneruption analogues. The flow behaviour emphasizes that volcano collapses can yield not only volcanic debris avalanches with restricted runouts, but also mobile lahars that enlarge by bulking as they flow. Volumes and hence inundation areas of collapse-runout lahars can increase greatly beyond their sources: the volume of the Casita lahar bulked to at least 2??6 times the contributing volume of the flank collapse and 4??2 times that of the debris flood. At least 78 per cent of the debris flow matrix (sediment < -1??0??; 2 mm) was entrained during flow. Copyright c 2004 John Wiley & Sons, Ltd.

  15. The violent Strombolian eruption of 10 ka Pelado shield volcano, Sierra Chichinautzin, Central Mexico

    Science.gov (United States)

    Lorenzo-Merino, A.; Guilbaud, M.-N.; Roberge, J.

    2018-03-01

    Pelado volcano is a typical example of an andesitic Mexican shield with a summital scoria cone. It erupted ca. 10 ka in the central part of an elevated plateau in what is today the southern part of Mexico City. The volcano forms a roughly circular, 10-km wide lava shield with two summital cones, surrounded by up to 2.7-m thick tephra deposits preserved up to a distance of 3 km beyond the shield. New cartographic, stratigraphic, granulometric, and componentry data indicate that Pelado volcano was the product of a single, continuous eruption marked by three stages. In the early stage, a > 1.5-km long fissure opened and was active with mild explosive activity. Intermediate and late stages were mostly effusive and associated with the formation of a 250-m high lava shield. Nevertheless, during these stages, the emission of lava alternated and/or coexisted with highly explosive events that deposited a widespread tephra blanket. In the intermediate stage, multiple vents were active along the fissure, but activity was centered at the main cone during the late stage. The final activity was purely effusive. The volcano emitted > 0.9 km3 dense-rock equivalent (DRE) of tephra and up to 5.6 km3 DRE of lavas. Pelado shares various features with documented "violent Strombolian" eruptions, including a high fragmentation index, large dispersal area, occurrence of plate tephra, high eruptive column, and simultaneous explosive and effusive activity. Our results suggest that the associated hazards (mostly tephra fallout and emplacement of lava) would seriously affect areas located up to 25 km from the vent for fallout and 5 km from the vent for lava, an important issue for large cities built near or on potentially active zones, such as Mexico City.

  16. Spectrogram analysis of selected tremor signals using short-time Fourier transform and continuous wavelet transform

    Energy Technology Data Exchange (ETDEWEB)

    Bartosch, T. [Erlanger-Nuernberg Univ., Erlanger (Germany). Lehrstul fuer Nachrichtentechnik I; Seidl, D. [Seismologisches Zentralobservatorium Graefenberg, Erlanegen (Greece). Bundesanstalt fuer Geiwissenschaften und Rohstoffe

    1999-06-01

    Among a variety of spectrogram methods short-time Fourier transform (STFT) and continuous wavelet transform (CWT) were selected to analyse transients in non-stationary signals. Depending on the properties of the tremor signals from the volcanos Mt. Stromboli, Mt. Semeru and Mt. Pinatubo were analyzed using both methods. The CWT can also be used to extend the definition of coherency into a time-varying coherency spectrogram. An example is given using array data from the volcano Mt. Stromboli (Italy).

  17. Q-values and Attenuation of the Shallow Crust Under Uturuncu Volcano, Bolivia

    Science.gov (United States)

    Mcfarlin, H. L.; McNutt, S. R.; Thompson, G.

    2017-12-01

    Uturuncu Volcano, located in the Altiplano-Puna region of the central Andes, near the border of Bolivia and Chile, has been shown to be inflating at a rate of 1-2 cm/yr over an area that is about 70 km wide. The PLUTONS project deployed 28 broadband seismometers around Uturuncu from April 2009 to October 2012. Several thousand shallow (depth < 20 km) local earthquakes were recorded. Attenuation of seismic waves along travel paths for these local crustal earthquakes can be measured by calculating Q-values, which we have performed using the method of single station spectral ratios by Frankel (1982). Large scatter in the Q-values for various distances and travel times appear to be a function of variations in source depth, focal mechanism, and back azimuth. Preliminary Q-values were calculated for azimuths in 30° increments in sectors around each station. Estimates for Q range from about 60 to 700, with many showing a low Q in the direction of the summit from each station. This suggests that the volcanic pile is more highly attenuating than the surrounding crust.

  18. Volcano hazards in the San Salvador region, El Salvador

    Science.gov (United States)

    Major, J.J.; Schilling, S.P.; Sofield, D.J.; Escobar, C.D.; Pullinger, C.R.

    2001-01-01

    San Salvador volcano is one of many volcanoes along the volcanic arc in El Salvador (figure 1). This volcano, having a volume of about 110 cubic kilometers, towers above San Salvador, the country’s capital and largest city. The city has a population of approximately 2 million, and a population density of about 2100 people per square kilometer. The city of San Salvador and other communities have gradually encroached onto the lower flanks of the volcano, increasing the risk that even small events may have serious societal consequences. San Salvador volcano has not erupted for more than 80 years, but it has a long history of repeated, and sometimes violent, eruptions. The volcano is composed of remnants of multiple eruptive centers, and these remnants are commonly referred to by several names. The central part of the volcano, which contains a large circular crater, is known as El Boquerón, and it rises to an altitude of about 1890 meters. El Picacho, the prominent peak of highest elevation (1960 meters altitude) to the northeast of the crater, and El Jabali, the peak to the northwest of the crater, represent remnants of an older, larger edifice. The volcano has erupted several times during the past 70,000 years from vents central to the volcano as well as from smaller vents and fissures on its flanks [1] (numerals in brackets refer to end notes in the report). In addition, several small cinder cones and explosion craters are located within 10 kilometers of the volcano. Since about 1200 A.D., eruptions have occurred almost exclusively along, or a few kilometers beyond, the northwest flank of the volcano, and have consisted primarily of small explosions and emplacement of lava flows. However, San Salvador volcano has erupted violently and explosively in the past, even as recently as 800 years ago. When such eruptions occur again, substantial population and infrastructure will be at risk. Volcanic eruptions are not the only events that present a risk to local

  19. Chemical compositions of lavas from Myoko volcano group

    International Nuclear Information System (INIS)

    Hasenaka, Toshiaki; Yoshida, Takeyoshi; Hayatsu, Kenji.

    1995-01-01

    In the volcanic rocks produced in island arc and continental margin arc, the phenomena of magma mixing is observed considerably generally. The research on these phenomena has been carried out also in Japan, and the periodically refilled magma chamber model has been proposed. In this report, the results of the photon activation analysis for the volcanic rock samples of Myoko volcano, for which the magma chamber model that the supply of basalt magma is periodically received was proposed, and of which the age of eruption and the stratigraphy are clearly known, are shown, and the above model is examined together with the published data of fluorescent X-ray analysis and others. The history of activities and the rate of magma extrusion of Myoko volcano group are described. The modal compositions of the volcanic rock samples of Myoko and Kurohime volcanos, for which photon activation analysis was carried out, are shown and discussed. The results of the analysis of the chemical composition of 39 volcanic rock samples from Myoko, Kurohime and Iizuna volcanos are shown. The primary magma in Myoko volcano group, the crystallization differentiation depth and moisture content of magma in Myoko and Kurohime volcanos, the presumption of Felsic and Mafic end-members in R type andesite in Myoko volcano group, and the change of magma composition with lapse of time are described. (K.I.)

  20. Chemical compositions of lavas from Myoko volcano group

    Energy Technology Data Exchange (ETDEWEB)

    Hasenaka, Toshiaki; Yoshida, Takeyoshi [Tohoku Univ., Sendai (Japan). Faculty of Science; Hayatsu, Kenji

    1995-08-01

    In the volcanic rocks produced in island arc and continental margin arc, the phenomena of magma mixing is observed considerably generally. The research on these phenomena has been carried out also in Japan, and the periodically refilled magma chamber model has been proposed. In this report, the results of the photon activation analysis for the volcanic rock samples of Myoko volcano, for which the magma chamber model that the supply of basalt magma is periodically received was proposed, and of which the age of eruption and the stratigraphy are clearly known, are shown, and the above model is examined together with the published data of fluorescent X-ray analysis and others. The history of activities and the rate of magma extrusion of Myoko volcano group are described. The modal compositions of the volcanic rock samples of Myoko and Kurohime volcanos, for which photon activation analysis was carried out, are shown and discussed. The results of the analysis of the chemical composition of 39 volcanic rock samples from Myoko, Kurohime and Iizuna volcanos are shown. The primary magma in Myoko volcano group, the crystallization differentiation depth and moisture content of magma in Myoko and Kurohime volcanos, the presumption of Felsic and Mafic end-members in R type andesite in Myoko volcano group, and the change of magma composition with lapse of time are described. (K.I.)

  1. SAR interferometry applications on active volcanoes. State of the art and perspectives for volcano monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Puglisi, G.; Coltelli, M. [Istituto Nazionale di Geofisica e Vulcanologia, Catania (Italy)

    2001-02-01

    In this paper the application of the Synthetic Aperture Radar Interferometry (INSAR) on volcanology is analysed. Since it is not a real novelty among the different applications of INSAR in Earth Observation activities, at the beginning of this paper it is analysed the state of the art of the researches in this field. During the discussion, the point of view of volcanologists is favoured because it is considered that the first applications were often badly aimed. Consequently, the initial INSAR performances in volcanology were overrated with respect to the real capabilities of this technique. This fact lead to discover some unexpected limitations in INSAR usage in volcano monitoring, but, at the same time, spurred on scientists to overcome these drawbacks. The results achieved recently allow to better apply SAR to volcanology; in the paper a possible operative work-plan aimed at introducing INSAR in the volcano monitoring system is presented.

  2. Mount Meager Volcano, Canada: a Case Study for Landslides on Glaciated Volcanoes

    Science.gov (United States)

    Roberti, G. L.; Ward, B. C.; van Wyk de Vries, B.; Falorni, G.; Perotti, L.; Clague, J. J.

    2015-12-01

    Mount Meager is a strato-volcano massif in the Northern Cascade Volcanic Arc (Canada) that erupted in 2350 BP, the most recent in Canada. To study the stability of the Massif an international research project between France ( Blaise Pascal University), Italy (University of Turin) and Canada (Simon Fraser University) and private companies (TRE - sensing the planet) has been created. A complex history of glacial loading and unloading, combined with weak, hydrothermally altered rocks has resulted in a long record of catastrophic landslides. The most recent, in 2010 is the third largest (50 x 106 m3) historical landslide in Canada. Mount Meager is a perfect natural laboratory for gravity and topographic processes such as landslide activity, permafrost and glacial dynamics, erosion, alteration and uplift on volcanoes. Research is aided by a rich archive of aerial photos of the Massif (1940s up to 2006): complete coverage approximately every 10 years. This data set has been processed and multi-temporal, high resolution Orthophoto and DSMs (Digital Surface Models) have been produced. On these digital products, with the support on field work, glacial retreat and landslide activity have been tracked and mapped. This has allowed for the inventory of unstable areas, the identification of lava flows and domes, and the general improvement on the geologic knowledge of the massif. InSAR data have been used to monitor the deformation of the pre-2010 failure slope. It will also be used to monitor other unstable slopes that potentially can evolve to catastrophic collapses of up to 1 km3 in volume, endangering local communities downstream the volcano. Mount Meager is definitively an exceptional site for studying the dynamics of a glaciated, uplifted volcano. The methodologies proposed can be applied to other volcanic areas with high erosion rates such as Alaska, Cascades, and the Andes.

  3. Spatial Distribution of b-value of the Copahue volcano during 2012-2014 eruptive period: Relationship between magmatic and hydrothermal system

    Science.gov (United States)

    Lazo, Jonathan; Basualto, Daniel; Bengoa, Cintia; Cardona, Carlos; Franco, Luis; Gil-Cruz, Fernando; Hernández, Erasmo; Lara, Luis; Lundgren, Paul; Medina, Roxana; Morales, Sergio; Peña, Paola; Quijada, Jonathan; Samsonov, Sergey; San Martin, Juan; Valderrama, Oscar

    2015-04-01

    Temporal and spatial variations of b-value have been interpreted as regional stress changes on active tectonic zones or magma ascent and/or hydrothermal fluids mobilization that could affect to active volcanic arc. Increasing of fluids pressure, medium heterogeneities or temperature changes would be the cause of these variations. The Copahue volcano is a shield strato-volcano that has been edified on the western margin of the Caviahue Caldera, located in the international border between Chile and Argentina, which contain an important geothermic field and is located at a horse-tail structure of the Liquiñe-Ofqui Fault Zone. The pre-fracture nature of its basement, as well as an extensive geothermic field, would be producing very complex conditions to fluids movement that could be exploring to use the 'b' value of the recorded seismicity between 2012 and 2014. Based in the database of VT seismic events, we used 2.073 events to calculate the b-value to obtain the 2D and 3D distribution maps. Results showed two anomalous zones: the first one located 9 Km to NE of the active crater, 3-6 Km depth, with high b-values (>1.2) that is associated with a very high production rate of small earthquakes that could suggest a brittle zone, located in the active geothermal field. The second zone, showed a low b-values (~ 0.7), located to east of the volcano edifice at volcano sitting on top of a geothermal system, the b-value offers a tool to understand the distribution of the seismic sources and hence a physical constrain for the coupled magmatic/hydrothermal system.

  4. 3D electrical conductivity tomography of volcanoes

    Science.gov (United States)

    Soueid Ahmed, A.; Revil, A.; Byrdina, S.; Coperey, A.; Gailler, L.; Grobbe, N.; Viveiros, F.; Silva, C.; Jougnot, D.; Ghorbani, A.; Hogg, C.; Kiyan, D.; Rath, V.; Heap, M. J.; Grandis, H.; Humaida, H.

    2018-05-01

    Electrical conductivity tomography is a well-established galvanometric method for imaging the subsurface electrical conductivity distribution. We characterize the conductivity distribution of a set of volcanic structures that are different in terms of activity and morphology. For that purpose, we developed a large-scale inversion code named ECT-3D aimed at handling complex topographical effects like those encountered in volcanic areas. In addition, ECT-3D offers the possibility of using as input data the two components of the electrical field recorded at independent stations. Without prior information, a Gauss-Newton method with roughness constraints is used to solve the inverse problem. The roughening operator used to impose constraints is computed on unstructured tetrahedral elements to map complex geometries. We first benchmark ECT-3D on two synthetic tests. A first test using the topography of Mt. St Helens volcano (Washington, USA) demonstrates that we can successfully reconstruct the electrical conductivity field of an edifice marked by a strong topography and strong variations in the resistivity distribution. A second case study is used to demonstrate the versatility of the code in using the two components of the electrical field recorded on independent stations along the ground surface. Then, we apply our code to real data sets recorded at (i) a thermally active area of Yellowstone caldera (Wyoming, USA), (ii) a monogenetic dome on Furnas volcano (the Azores, Portugal), and (iii) the upper portion of the caldera of Kīlauea (Hawai'i, USA). The tomographies reveal some of the major structures of these volcanoes as well as identifying alteration associated with high surface conductivities. We also review the petrophysics underlying the interpretation of the electrical conductivity of fresh and altered volcanic rocks and molten rocks to show that electrical conductivity tomography cannot be used as a stand-alone technique due to the non-uniqueness in

  5. Muon imaging of volcanoes with Cherenkov telescopes

    Science.gov (United States)

    Carbone, Daniele; Catalano, Osvaldo; Cusumano, Giancarlo; Del Santo, Melania; La Parola, Valentina; La Rosa, Giovanni; Maccarone, Maria Concetta; Mineo, Teresa; Pareschi, Giovanni; Sottile, Giuseppe; Zuccarello, Luciano

    2017-04-01

    The quantitative understanding of the inner structure of a volcano is a key feature to model the processes leading to paroxysmal activity and, hence, to mitigate volcanic hazards. To pursue this aim, different geophysical techniques are utilized, that are sensitive to different properties of the rocks (elastic, electrical, density). In most cases, these techniques do not allow to achieve the spatial resolution needed to characterize the shallowest part of the plumbing system and may require dense measurements in active zones, implying a high level of risk. Volcano imaging through cosmic-ray muons is a promising technique that allows to overcome the above shortcomings. Muons constantly bombard the Earth's surface and can travel through large thicknesses of rock, with an energy loss depending on the amount of crossed matter. By measuring the absorption of muons through a solid body, one can deduce the density distribution inside the target. To date, muon imaging of volcanic structures has been mainly achieved with scintillation detectors. They are sensitive to noise sourced from (i) the accidental coincidence of vertical EM shower particles, (ii) the fake tracks initiated from horizontal high-energy electrons and low-energy muons (not crossing the target) and (iii) the flux of upward going muons. A possible alternative to scintillation detectors is given by Cherenkov telescopes. They exploit the Cherenkov light emitted when charged particles (like muons) travel through a dielectric medium, with velocity higher than the speed of light. Cherenkov detectors are not significantly affected by the above noise sources. Furthermore, contrarily to scintillator-based detectors, Cherenkov telescopes permit a measurement of the energy spectrum of the incident muon flux at the installation site, an issue that is indeed relevant for deducing the density distribution inside the target. In 2014, a prototype Cherenkov telescope was installed at the Astrophysical Observatory of Serra

  6. Large-N in Volcano Settings: Volcanosri

    Science.gov (United States)

    Lees, J. M.; Song, W.; Xing, G.; Vick, S.; Phillips, D.

    2014-12-01

    We seek a paradigm shift in the approach we take on volcano monitoring where the compromise from high fidelity to large numbers of sensors is used to increase coverage and resolution. Accessibility, danger and the risk of equipment loss requires that we develop systems that are independent and inexpensive. Furthermore, rather than simply record data on hard disk for later analysis we desire a system that will work autonomously, capitalizing on wireless technology and in field network analysis. To this end we are currently producing a low cost seismic array which will incorporate, at the very basic level, seismological tools for first cut analysis of a volcano in crises mode. At the advanced end we expect to perform tomographic inversions in the network in near real time. Geophone (4 Hz) sensors connected to a low cost recording system will be installed on an active volcano where triggering earthquake location and velocity analysis will take place independent of human interaction. Stations are designed to be inexpensive and possibly disposable. In one of the first implementations the seismic nodes consist of an Arduino Due processor board with an attached Seismic Shield. The Arduino Due processor board contains an Atmel SAM3X8E ARM Cortex-M3 CPU. This 32 bit 84 MHz processor can filter and perform coarse seismic event detection on a 1600 sample signal in fewer than 200 milliseconds. The Seismic Shield contains a GPS module, 900 MHz high power mesh network radio, SD card, seismic amplifier, and 24 bit ADC. External sensors can be attached to either this 24-bit ADC or to the internal multichannel 12 bit ADC contained on the Arduino Due processor board. This allows the node to support attachment of multiple sensors. By utilizing a high-speed 32 bit processor complex signal processing tasks can be performed simultaneously on multiple sensors. Using a 10 W solar panel, second system being developed can run autonomously and collect data on 3 channels at 100Hz for 6 months

  7. Surface deformation monitoring of Sinabung volcano using multi temporal InSAR method and GIS analysis for affected area assessment

    Science.gov (United States)

    Aditiya, A.; Aoki, Y.; Anugrah, R. D.

    2018-04-01

    Sinabung Volcano which located in northern part of Sumatera island is part of a hundred active volcano in Indonesia. Surface deformation is detected over Sinabung Volcano and surrounded area since the first eruption in 2010 after 400 years long rest. We present multi temporal Interferometric Synthetic Aperture Radar (InSAR) time-series method of ALOS-2 L-band SAR data acquired from December 2014 to July 2017 to reveal surface deformation with high spatial resolution. The method includes focusing the SAR data, generating interferogram and phase unwrapping using SNAPHU tools. The result reveal significant deformation over Sinabung Volcano areas at rates up to 10 cm during observation period and the highest deformation occurs in western part which is trajectory of lava. We concluded the observed deformation primarily caused by volcanic activity respectively after long period of rest. In addition, Geographic Information System (GIS) analysis produces disaster affected areas of Sinabung eruption. GIS is reliable technique to estimate the impact of the hazard scenario to the exposure data and develop scenarios of disaster impacts to inform their contingency and emergency plan. The GIS results include the estimated affected area divided into 3 zones based on pyroclastic lava flow and pyroclastic fall (incandescent rock and ash). The highest impact is occurred in zone II due to many settlements are scattered in this zone. This information will be support stakeholders to take emergency preparation for disaster reduction. The continuation of this high rate of decline tends to endanger the population in next periods.

  8. Overview of gas flux measurements from volcanoes of the global Network for Observation of Volcanic and Atmospheric Change (NOVAC)

    Science.gov (United States)

    Galle, Bo; Arellano, Santiago; Conde, Vladimir

    2015-04-01

    NOVAC, the Network for Observation of Volcanic and Atmospheric Change, was initiated in 2005 as a 5-years-long project financed by the European Union. Its main purpose is to create a global network for the study of volcanic atmospheric plumes and related geophysical phenomena by using state-of-the-art spectroscopic remote sensing technology. Up to 2014, 67 instruments have been installed at 25 volcanoes in 13 countries of Latin America, Italy, Democratic Republic of Congo, Reunion, Iceland, and Philippines, and efforts are being done to expand the network to other active volcanic zones. NOVAC has been a pioneer initiative in the community of volcanologists and embraces the objectives of the Word Organization of Volcano Observatories (WOVO) and the Global Earth Observation System of Systems (GEOSS). In this contribution, we present the results of the measurements of SO2 gas fluxes carried out within NOVAC, which for some volcanoes represent a record of more than 8 years of semi-continuous monitoring. The network comprises some of the most strongly degassing volcanoes in the world, covering a broad range of tectonic settings, levels of unrest, and potential risk. Examples of correlations with seismicity and other geophysical phenomena, environmental impact studies and comparisons with previous global estimates will be discussed as well as the significance of the database for further studies in volcanology and other geosciences.

  9. Dynamic triggering of volcano drumbeat-like seismicity at the Tatun volcano group in Taiwan

    Science.gov (United States)

    Lin, Cheng-Horng

    2017-07-01

    Periodical seismicity during eruptions has been observed at several volcanoes, such as Mount St. Helens and Soufrière Hills. Movement of magma is often considered one of the most important factors in its generation. Without any magma movement, drumbeat-like (or heartbeat-like) periodical seismicity was detected twice beneath one of the strongest fumarole sites (Dayoukeng) among the Tatun volcano group in northern Taiwan in 2015. Both incidences of drumbeat-like seismicity were respectively started after felt earthquakes in Taiwan, and then persisted for 1-2 d afterward with repetition intervals of ∼18 min between any two adjacent events. The phenomena suggest both drumbeat-like (heartbeat-like) seismicity sequences were likely triggered by dynamic waves generated by the two felt earthquakes. Thus, rather than any involvement of magma, a simplified pumping system within a degassing conduit is proposed to explain the generation of drumbeat-like seismicity. The collapsed rocks within the conduit act as a piston, which was repeatedly lifted up by ascending gas from a deeper reservoir and dropped down when the ascending gas was escaping later. These phenomena show that the degassing process is still very strong in the Tatun volcano group in Taiwan, even though it has been dormant for about several thousand years.

  10. Chile: Una Vision Politica, Economica y Social (Chile: A Political, Economic, and Social View).

    Science.gov (United States)

    Cortes-Hwang, Adriana

    1972-01-01

    This address seeks to explain in brief the historical background and political, economic, and social conditions leading to the democratic election of a Marxist president in Chile. A historical sketch of Chilean government from independence in 1810 is provided with a description of the situation just before Salvador Allende's election in 1969. Some…

  11. Nuclear public information activities in Chile; Programa de educacion publica de la energia nuclear en Chile

    Energy Technology Data Exchange (ETDEWEB)

    Munoz Quintana, R [Comision Chilena de Energia Nuclear, Santiago (Chile)

    1995-10-01

    Nuclear plans and developing programs in developing and developed countries are facing-in a higher or lower degree- opposition from public opinion. The objectives and contents of the public education program on nuclear energy in Chile are dealt with in this paper.

  12. The Mass Media and Political Socialization: Chile, 1970-2000

    Science.gov (United States)

    Walter, Amy R.

    2005-01-01

    This project seeks to determine the effect of the mass media on political attitudes and behaviors in Chile between the years 1970 and 2000. The relationship between the media and "political socialization" is just now gaining recognition in scholarly research, and Chile offers an excellent case study. This paper traces these two variables…

  13. Studies to Control Endemic Typhoid Fever in Chile

    Science.gov (United States)

    1985-09-01

    Society for Microbiology, Chapter 16. 10. Medina E, Yrarrazaval M. (1983) Fiebre tifoidea en Chile: Consideraciones epideniologicas. Revista Medica de...epidesiologia de la fiebre tifoidea . Boletin de !a Escuela de Medicina, Pontificia universidad catolica de Chile. 30:113-119. 14. Reyes H, Olea M, Hernandez

  14. Primer registro de Heliotropium amplexicaule (Heliotropiaceae) en Chile

    OpenAIRE

    Ibáñez, Sergio; Luebert, Federico; Gómez, Miguel

    2011-01-01

    The presence of the commonly known weed Heliotropium amplexicaule (Heliotropiaceae) is reported for Chile first time, from a collection recently made in Santiago. Its potential as weed in Chile is discussed in the context of the experience of other countries where the species has become naturalised.

  15. Adapting to climate variability and change in Chile's Maipo basin ...

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

    2014-04-09

    Apr 9, 2014 ... Given the region's role in Chile's national economy, a strategy for adapting to ... to Chile's economy, and may be threatened by future water stress. ... for the project, with the goal of bringing together government, business, and ...

  16. The Revolutionary Left and Terrorist Violence in Chile.

    Science.gov (United States)

    1986-06-01

    Fraude Electoral Designada por la Facultad de Derecho de la Pontifica Universidad de Chile," in Libro Blanco del Cambio de Gobierno de Chile, Editorial...Chilean law, could not be invaded by the police. The MIR never became a formal political party. It completely rejected the electoral process

  17. All projects related to Chile | Page 2 | IDRC - International ...

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

    ... living in poverty in the rural-urban territories of Chile, Colombia, and Mexico. ... Region: Brazil, Chile, Colombia, India ... Enhancing Women's Economic Empowerment Through Better Policies in Latin America ... Program: Employment and Growth ... Understanding Think Tank-University Relationships in Latin America.

  18. Childcare in Chile. The role of ethnicity and socioeconomic inequalities

    NARCIS (Netherlands)

    Cárcamo Leiva, Rodrigo Alejandro

    2014-01-01

    Chile has embarked on a road that must lead to the reduction of inequality gaps for the population. A public policy called Chile Growths With You has focused on an increase in the breadth of coverage of non-maternal care through childcare centers to provide equal opportunities in early childhood and

  19. [Health inequality gap in inmigrant versus local children in Chile].

    Science.gov (United States)

    Cabieses, Baltica; Chepo, Macarena; Oyarte, Marcela; Markkula, Niina; Bustos, Patricia; Pedrero, Víctor; Delgado, Iris

    2017-12-01

    Children and young international migrants face different health challenges compa red with the local population, particularly if they live in insecure environments or adverse social conditions. This study seeks to identify gaps in health outcomes of children between immigrant and local population in Chile. This study analyses data from three sources: (i) Born in Chile: Electronic records of antenatal visits from all municipal antenatal clinics of Recoleta in 2012; (ii) Growing up in Chile: Population survey "National Socioeconomic Characterization" (CASEN) from 2013 and (iii) Getting sick in Chile: Data of all hospital discharges in 2012, provided by the department of statistics and health information (DEIS) of the Ministry of Health. (I) Born in Chile: Im migrants more frequently have psychosocial risk (62.3% vs 50.1% in Chileans) and enter later into the program (63.1% vs 33.4% enter later than 14 weeks of pregnancy). All birth outcomes were better among immigrants (e.g. caesarean sections rates: 24.2% immigrants vs % Chileans). (ii) Growing up in Chile: A higher proportion of migrant children is outside the school system and lives in multidi mensional poverty (40% immigrants vs 23.2% Chileans). (iii) Getting sick in Chile: Injuries and other external causes were more frequent cause of hospitalisation among migrants (23.6%) than the local population (16.7%) aged between 7 and 14 years. Addressing the needs of the children in Chile, regardless of their immigration status, is an ethical, legal and moral imperative.

  20. Deep magma transport at Kilauea volcano, Hawaii

    Science.gov (United States)

    Wright, T.L.; Klein, F.W.

    2006-01-01

    The shallow part of Kilauea's magma system is conceptually well-understood. Long-period and short-period (brittle-failure) earthquake swarms outline a near-vertical magma transport path beneath Kilauea's summit to 20 km depth. A gravity high centered above the magma transport path demonstrates that Kilauea's shallow magma system, established early in the volcano's history, has remained fixed in place. Low seismicity at 4-7 km outlines a storage region from which magma is supplied for eruptions and intrusions. Brittle-failure earthquake swarms shallower than 5 km beneath the rift zones accompany dike emplacement. Sparse earthquakes extend to a decollement at 10-12 km along which the south flank of Kilauea is sliding seaward. This zone below 5 km can sustain aseismic magma transport, consistent with recent tomographic studies. Long-period earthquake clusters deeper than 40 km occur parallel to and offshore of Kilauea's south coast, defining the deepest seismic response to magma transport from the Hawaiian hot spot. A path connecting the shallow and deep long-period earthquakes is defined by mainshock-aftershock locations of brittle-failure earthquakes unique to Kilauea whose hypocenters are deeper than 25 km with magnitudes from 4.4 to 5.2. Separation of deep and shallow long-period clusters occurs as the shallow plumbing moves with the volcanic edifice, while the deep plumbing is centered over the hotspot. Recent GPS data agrees with the volcano-propagation vector from Kauai to Maui, suggesting that Pacific plate motion, azimuth 293.5?? and rate of 7.4 cm/yr, has been constant over Kilauea's lifetime. However, volcano propagation on the island of Hawaii, azimuth 325??, rate 13 cm/yr, requires southwesterly migration of the locus of melting within the broad hotspot. Deep, long-period earthquakes lie west of the extrapolated position of Kilauea backward in time along a plate-motion vector, requiring southwesterly migration of Kilauea's magma source. Assumed ages of 0

  1. Space Radar Image of Kilauea Volcano, Hawaii

    Science.gov (United States)

    1994-01-01

    This is a deformation map of the south flank of Kilauea volcano on the big island of Hawaii, centered at 19.5 degrees north latitude and 155.25 degrees west longitude. The map was created by combining interferometric radar data -- that is data acquired on different passes of the space shuttle which are then overlayed to obtain elevation information -- acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar during its first flight in April 1994 and its second flight in October 1994. The area shown is approximately 40 kilometers by 80 kilometers (25 miles by 50 miles). North is toward the upper left of the image. The colors indicate the displacement of the surface in the direction that the radar instrument was pointed (toward the right of the image) in the six months between images. The analysis of ground movement is preliminary, but appears consistent with the motions detected by the Global Positioning System ground receivers that have been used over the past five years. The south flank of the Kilauea volcano is among the most rapidly deforming terrains on Earth. Several regions show motions over the six-month time period. Most obvious is at the base of Hilina Pali, where 10 centimeters (4 inches) or more of crustal deformation can be seen in a concentrated area near the coastline. On a more localized scale, the currently active Pu'u O'o summit also shows about 10 centimeters (4 inches) of change near the vent area. Finally, there are indications of additional movement along the upper southwest rift zone, just below the Kilauea caldera in the image. Deformation of the south flank is believed to be the result of movements along faults deep beneath the surface of the volcano, as well as injections of magma, or molten rock, into the volcano's 'plumbing' system. Detection of ground motions from space has proven to be a unique capability of imaging radar technology. Scientists hope to use deformation data acquired by SIR-C/X-SAR and future imaging

  2. Modernization of the USGS Hawaiian Volcano Observatory Seismic Processing Infrastructure

    Science.gov (United States)

    Antolik, L.; Shiro, B.; Friberg, P. A.

    2016-12-01

    The USGS Hawaiian Volcano Observatory (HVO) operates a Tier 1 Advanced National Seismic System (ANSS) seismic network to monitor, characterize, and report on volcanic and earthquake activity in the State of Hawaii. Upgrades at the observatory since 2009 have improved the digital telemetry network, computing resources, and seismic data processing with the adoption of the ANSS Quake Management System (AQMS) system. HVO aims to build on these efforts by further modernizing its seismic processing infrastructure and strengthen its ability to meet ANSS performance standards. Most notably, this will also allow HVO to support redundant systems, both onsite and offsite, in order to provide better continuity of operation during intermittent power and network outages. We are in the process of implementing a number of upgrades and improvements on HVO's seismic processing infrastructure, including: 1) Virtualization of AQMS physical servers; 2) Migration of server operating systems from Solaris to Linux; 3) Consolidation of AQMS real-time and post-processing services to a single server; 4) Upgrading database from Oracle 10 to Oracle 12; and 5) Upgrading to the latest Earthworm and AQMS software. These improvements will make server administration more efficient, minimize hardware resources required by AQMS, simplify the Oracle replication setup, and provide better integration with HVO's existing state of health monitoring tools and backup system. Ultimately, it will provide HVO with the latest and most secure software available while making the software easier to deploy and support.

  3. Element fluxes from Copahue Volcano, Argentina

    Science.gov (United States)

    Varekamp, J. C.

    2003-12-01

    Copahue volcano in Argentina has an active volcano-magmatic hydrothermal system that emits fluids with pH=0.3 that feed a river system. River flux measurements and analytical data provide element flux data from 1997 to 2003, which includes the eruptive period of July to December 2000. The fluids have up to 6.5 percent sulfate, 1 percent Cl and ppm levels of B, As, Cu, Zn and Pb. The hydrothermal system acts as a perfect scrubber for magmatic gases during the periods of passive degassing, although the dissolved magmatic gases are modified through water rock interaction and mineral precipitation. The magmatic SO2 disproportionates into sulfate and liquid elemental sulfur at about 300 C; the sulfate is discharged with the fluids, whereas the liquid sulfur is temporarily retained in the reservoir but ejected during phreatic and hydrothermal eruptions. The intrusion and chemical attack of new magma in the hydrothermal reservoir in early 2000 was indicated by strongly increased Mg concentrations and Mg fluxes, and higher Mg/Cl and Mg/K values. The hydrothermal discharge has acidified a large glacial lake (0.5 km3) to pH=2 and the lake effluents acidify the exiting river. Even more than 100 km downstream, the effects of acid pulses from the lake are evident from red coated boulders and fish die-offs. The river-bound sulfate fluxes from the system range from 70 to 200 kilotonnes/year. The equivalent SO2 output of the whole volcanic system ranges from 150 to 500 tonnes/day, which includes the fraction of native sulfur that formed inside the mountain but does not include the release of SO2 into the atmosphere during the eruptions. Trace element fluxes of the river will be scaled up and compared with global element fluxes from meteoric river waters (subterranean volcanic weathering versus watershed weathering).

  4. Geomechanical rock properties of a basaltic volcano

    Directory of Open Access Journals (Sweden)

    Lauren N Schaefer

    2015-06-01

    Full Text Available In volcanic regions, reliable estimates of mechanical properties for specific volcanic events such as cyclic inflation-deflation cycles by magmatic intrusions, thermal stressing, and high temperatures are crucial for building accurate models of volcanic phenomena. This study focuses on the challenge of characterizing volcanic materials for the numerical analyses of such events. To do this, we evaluated the physical (porosity, permeability and mechanical (strength properties of basaltic rocks at Pacaya Volcano (Guatemala through a variety of laboratory experiments, including: room temperature, high temperature (935 °C, and cyclically-loaded uniaxial compressive strength tests on as-collected and thermally-treated rock samples. Knowledge of the material response to such varied stressing conditions is necessary to analyze potential hazards at Pacaya, whose persistent activity has led to 13 evacuations of towns near the volcano since 1987. The rocks show a non-linear relationship between permeability and porosity, which relates to the importance of the crack network connecting the vesicles in these rocks. Here we show that strength not only decreases with porosity and permeability, but also with prolonged stressing (i.e., at lower strain rates and upon cooling. Complimentary tests in which cyclic episodes of thermal or load stressing showed no systematic weakening of the material on the scale of our experiments. Most importantly, we show the extremely heterogeneous nature of volcanic edifices that arise from differences in porosity and permeability of the local lithologies, the limited lateral extent of lava flows, and the scars of previous collapse events. Input of these process-specific rock behaviors into slope stability and deformation models can change the resultant hazard analysis. We anticipate that an increased parameterization of rock properties will improve mitigation power.

  5. A catalog of Acroceridae (Diptera) from Chile.

    Science.gov (United States)

    GonzÁlez, Christian R; Elgueta, Mario; Ramirez, Francisco

    2018-01-18

    A catalog of the Acroceridae from Chile is provided. All valid names and synonyms are presented, totaling 33 species and nine genera for the country. All references known to us from the taxonomic and biological literature, including information about name, author, year of publication, page number, type species, type locality and references are given. Type material of different authors was revised. The species Lasia cuprea is revalidated. The geographical distribution of the different species is recorded from the revised collections and bibliographic data. Holops cyaneus Philippi, 1865 is designated as type species of Holops Philippi, 1865.

  6. EFECTOS DEL EMBARAZO ADOLESCENTE EN CHILE

    OpenAIRE

    Loyola Heufemann, AMANDA

    2014-01-01

    Los efectos del embarazo adolescente en Chile han sido poco estudiados aun cuando existe diversa literatura para el resto del mundo, en especial para países desarrollados. Este trabajo estima el efecto del embarazo adolescente sobre la asistencia o completitud de la educación secundaria, años de escolaridad y participación laboral. Usando datos de corte transversal del a˜no 2012 y un enfoque de variable instrumental a trav´es del uso de la entrega comunal de la píldora anticoncept...

  7. FORESIGHT TEST CASE CHILE: UNIACC UNIVERSITY

    Directory of Open Access Journals (Sweden)

    José Nicolás Vizcaya Carrillo

    2011-04-01

    Full Text Available it is true that all human activities today are capable of analysis and prospective projection, confirmed there are a number of areas of knowledge which are considered key to the development of mankind and therefore of each company in each country is to see the evolution of the relevant future. It is true that today there are hundreds of professional disciplines that are studied and are performed as day to day and that play important roles in the welfare and development of society and in particular if this trial will be analyzed in the development of techniques current looking for Chile.

  8. Pentecostalism and Politics in Neoliberal Chile

    Directory of Open Access Journals (Sweden)

    Martin Lindhardt

    2013-02-01

    Full Text Available Este artículo investiga las relaciones históricas y contemporáneas entre el Pentecostalismo y la política en Chile. La primera parte del artículo provee un resumen histórico del crecimiento y consolidación de la religión Pentecostal en relación a diferentes ambientes políticos. En este artículo se esclarecen además las diferentes posturas Pentecostales hacia la esfera política. En particular hago hincapié, en cómo surge una cultura de desencanto político en el Chile post-dictatorial que crea un vacío simbólico, el cual trae como consecuencia el nacimiento de movimientos religiosos. En la segunda parte de este artículo se discute las posibles afinidades entre el Pentecostalismo, como una cultura religiosa, y los principios democráticos. El argumento es que a pesar de que el Pentecostalismo puede contener algunas cualidades democráticas, también existe una compatibilidad notable entre la visión teísta e individualista Pentecostal acerca de los cambios sociales, y un orden social neoliberal, en donde la indolencia política se expande y en donde predomina un sentido de progreso individual y no colectivo. English: This article explores historical and contemporary relationships between Pentecostalism and politics in Chile. The first part of the article provides an historical account of the growth and consolidation of Pentecostal religion within changing political environments and sheds light on Pentecostal stances to and involvements with the political sphere. In particular, it focuses on how a culture of political disenchantment has emerged in post-dictatorial neo-liberal Chile, creating a symbolic void that can be filled by religious movements. The second part of the article discusses possible affinities between Pentecostalism as a religious culture and democratic principles and values. It argues that although Pentecostalism may contain certain democratic qualities, there is also a striking compatibility between, on the one

  9. Monetary Policy in Chile: a black box?

    OpenAIRE

    Angel Cabrera; Luis Felipe Lagos

    2000-01-01

    This paper studies monetary policy in Chile during the 1986-1997 period. We concentrate in understanding the monetary transmission mechanism by which the Central Bank instrument—the real interest rate—affects total expenditure, output and the inflation rate. The methodology used is structural VARS. We find a weak effect of the interest rate on all the variables. The interest rate has a significant effect on the expenditure-output gap. Both the interest rate and the expenditure-output gap have...

  10. Center for oceanographic research opens in Chile

    Science.gov (United States)

    Lange, Carina B.; Ulloa, Osvaldo

    The Humboldt Current System, with its coastal upwelling ecosystem off Peru and Chile, is one of the most productive marine systems in the world. Here, significant exchange of heat and CO2 takes place between the ocean and the atmosphere due to upwelling of sub-surface, cold, nutrient-rich, CO2-saturated waters. In addition, the eastern South Pacific holds one of the three most important oxygen minimum zones of the global ocean. Through the biologically mediated process of denitrification, the oxygen minimum zone contributes to the global sink of nitrogen in the ocean and as a source of the greenhouse gas N2O to the atmosphere.

  11. Chile Successfully Halts Rise in Childhood Obesity

    International Nuclear Information System (INIS)

    Gorisek, Aleksandra Sasa

    2014-01-01

    The increasing prevalence of childhood obesity in Latin America has become a cause for concern. The IAEA has worked closely with the Institute of Nutrition and Food Technology (INTA) at the University of Chile since 1997 to address the problem of malnutrition in the country. In Santiago, the Laboratory of Energy Metabolism and Stable Isotopes was established in 1998 with the help of the IAEA to provide an isotope ratio mass spectrometer and training in the use of stable isotope techniques to assess body composition, infant feeding practices and total daily energy expenditure

  12. Magma supply, storage, and transport at shield-stage Hawaiian volcanoes: Chapter 5 in Characteristics of Hawaiian volcanoes

    Science.gov (United States)

    Poland, Michael P.; Miklius, Asta; Montgomery-Brown, Emily K.; Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.

    2014-01-01

    The characteristics of magma supply, storage, and transport are among the most critical parameters governing volcanic activity, yet they remain largely unconstrained because all three processes are hidden beneath the surface. Hawaiian volcanoes, particularly Kīlauea and Mauna Loa, offer excellent prospects for studying subsurface magmatic processes, owing to their accessibility and frequent eruptive and intrusive activity. In addition, the Hawaiian Volcano Observatory, founded in 1912, maintains long records of geological, geophysical, and geochemical data. As a result, Hawaiian volcanoes have served as both a model for basaltic volcanism in general and a starting point for many studies of volcanic processes.

  13. Extinction and recolonization of local populations on a growing shield volcano.

    Science.gov (United States)

    Carson, H L; Lockwood, J P; Craddock, E M

    1990-01-01

    Volcanic action has resulted in the burial of the surfaces of Mauna Loa and Kilauea, Hawaii, by new lava flows at rates as high as 90% per 1000 years. Local populations of organisms on such volcanoes are continually being exterminated; survival of the species requires colonization of younger flows. Certain populations of the endemic Hawaiian species Drosophila silvestris exemplify such events in microcosm. Local populations at the base of an altitudinal cline were destroyed by two explosive eruptions within the last 2100 years. Natural recolonization restored the cline except for one young population that is genetically discordant with altitude. Images PMID:11607102

  14. Continuous Problem of Function Continuity

    Science.gov (United States)

    Jayakody, Gaya; Zazkis, Rina

    2015-01-01

    We examine different definitions presented in textbooks and other mathematical sources for "continuity of a function at a point" and "continuous function" in the context of introductory level Calculus. We then identify problematic issues related to definitions of continuity and discontinuity: inconsistency and absence of…

  15. Imaging irregular magma reservoirs with InSAR and GPS observations: Application to Kilauea and Copahue volcanoes

    Science.gov (United States)

    Lundgren, P.; Camacho, A.; Poland, M. P.; Miklius, A.; Samsonov, S. V.; Milillo, P.

    2013-12-01

    The availability of synthetic aperture radar (SAR) interferometry (InSAR) data has increased our awareness of the complexity of volcano deformation sources. InSAR's spatial completeness helps identify or clarify source process mechanisms at volcanoes (i.e. Mt. Etna east flank motion; Lazufre crustal magma body; Kilauea dike complexity) and also improves potential model realism. In recent years, Bayesian inference methods have gained widespread use because of their ability to constrain not only source model parameters, but also their uncertainties. They are computationally intensive, however, which tends to limit them to a few geometrically rather simple source representations (for example, spheres). An alternative approach involves solving for irregular pressure and/or density sources from a three-dimensional (3-D) grid of source/density cells. This method has the ability to solve for arbitrarily shaped bodies of constant absolute pressure/density difference. We compare results for both Bayesian (a Markov chain Monte Carlo algorithm) and the irregular source methods for two volcanoes: Kilauea, Hawaii, and Copahue, Argentina-Chile border. Kilauea has extensive InSAR and GPS databases from which to explore the results for the irregular method with respect to the Bayesian approach, prior models, and an extensive set of ancillary data. One caveat, however, is the current restriction in the irregular model inversion to volume-pressure sources (and at a single excess pressure change), which limits its application in cases where sources such as faults or dikes are present. Preliminary results for Kilauea summit deflation during the March 2011 Kamoamoa eruption suggests a northeast-elongated magma body lying roughly 1-1.5 km below the surface. Copahue is a southern Andes volcano that has been inflating since early 2012, with intermittent summit eruptive activity since late 2012. We have an extensive InSAR time series from RADARSAT-2 and COSMO-SkyMed data, although both are

  16. Sub-crustal seismic activity beneath Klyuchevskoy Volcano

    Science.gov (United States)

    Carr, M. J.; Droznina, S.; Levin, V. L.; Senyukov, S.

    2013-12-01

    Seismic activity is extremely vigorous beneath the Klyuchevskoy Volcanic Group (KVG). The unique aspect is the distribution in depth. In addition to upper-crustal seismicity, earthquakes take place at depths in excess of 20 km. Similar observations are known in other volcanic regions, however the KVG is unique in both the number of earthquakes and that they occur continuously. Most other instances of deep seismicity beneath volcanoes appear to be episodic or transient. Digital recording of seismic signals started at the KVG in early 2000s.The dense local network reliably locates earthquakes as small as ML~1. We selected records of 20 earthquakes located at depths over 20 km. Selection was based on the quality of the routine locations and the visual clarity of the records. Arrivals of P and S waves were re-picked, and hypocentral parameters re-established. Newl locations fell within the ranges outlined by historical seismicity, confirming the existence of two distinct seismically active regions. A shallower zone is at ~20 km depth, and all hypocenters are to the northeast of KVG, in a region between KVG and Shiveluch volcano. A deeper zone is at ~30 km, and all hypocenters cluster directly beneath the edifice of the Kyuchevskoy volcano. Examination of individual records shows that earthquakes in both zones are tectonic, with well-defined P and S waves - another distinction of the deep seismicity beneath KVG. While the upper seismic zone is unquestionably within the crust, the provenance of the deeper earthquakes is enigmatic. The crustal structure beneath KVG is highly complex, with no agreed-upon definition of the crust-mantle boundary. Rather, a range of values, from under 30 to over 40 km, exists in the literature. Similarly, a range of velocity structures has been reported. Teleseismic receiver functions (RFs) provide a way to position the earthquakes with respect to the crust-mantle boundary. We compare the differential travel times of S and P waves from deep

  17. Estudio del campo ocupacional del traductor en Santiago de Chile (A Study of Opportunities for Professional Translators in Santiago, Chile).

    Science.gov (United States)

    Cabrera, Ileana; And Others

    A study of translation as a profession in Chile covered two areas: a diagnostic study of the real need for literary, scientific, and technical translations, and a followup study of graduates of the translation degree program at the Catholic Pontifical University of Chile (Santiago). The analysis considered the relationship between the need for…

  18. One hundred years of volcano monitoring in Hawaii

    Science.gov (United States)

    Kauahikaua, Jim; Poland, Mike

    2012-01-01

    In 2012 the Hawaiian Volcano Observatory (HVO), the oldest of five volcano observatories in the United States, is commemorating the 100th anniversary of its founding. HVO's location, on the rim of Kilauea volcano (Figure 1)—one of the most active volcanoes on Earth—has provided an unprecedented opportunity over the past century to study processes associated with active volcanism and develop methods for hazards assessment and mitigation. The scientifically and societally important results that have come from 100 years of HVO's existence are the realization of one man's vision of the best way to protect humanity from natural disasters. That vision was a response to an unusually destructive decade that began the twentieth century, a decade that saw almost 200,000 people killed by the effects of earthquakes and volcanic eruptions.

  19. The Active Lava Flows of Kilauea Volcano, Hawaii

    Indian Academy of Sciences (India)

    'lahar' is from Indonesia, a country with some of the most active and destructive volcanoes .... tourist-dependent businesses such as airlines, rental car compa- nies, and hotels. ... excellent viewing conditions and photo opportunities. The heat.

  20. Vegetation damage and recovery after Chiginagak Volcano Crater drainage event

    Data.gov (United States)

    Department of the Interior — From August 20 — 23, 2006, I revisited Chiginigak volcano to document vegetation recovery after the crater drainage event that severely damaged vegetation in May of...

  1. Two new Liolaemus lizards from the Andean highlands of Southern Chile (Squamata, Iguania, Liolaemidae)

    Science.gov (United States)

    Troncoso-Palacios, Jaime; Diaz, Hugo A.; Puas, German I.; Riveros-Riffo, Edvin; Elorza, Alvaro A.

    2016-01-01

    Abstract Liolaemus is a diverse genus of lizards, subdivided into two subgenera: Liolaemus (sensu stricto) and Eulaemus, distributed mainly in Chile and Argentina. The Liolaemus elongatus-kriegi complex is the most diverse group within Liolaemus (sensu stricto), especially the species closely related to Liolaemus elongatus, which form a clade currently comprising nine species. Several Chilean species of this group have been recently described, mainly from volcanoes and poorly explored mountains. Here molecular and morphological evidence are provided for a new species of the Liolaemus elongatus clade, which is characterized by its small size and lack of dorsal pattern, unusual features for the species of this group of lizards. Additionally, the lack of precloacal pores in males of Liolaemus (sensu stricto) is a trait found in few species, which do not constitute a monophyletic group. A second new southern Chilean species is also described, without precloacal pores and supported by molecular phylogenetics to be related to Liolaemus villaricensis. Both new species were found in the same locality, near a lake located in a pre-Andean zone with Araucaria and Nothofagus forest. The two species are dedicated to prominent Lonkos (tribal chiefs) of the Mapuche and Pehuenche people: Janequeo and Leftraru. Additionally, the phylogenetic results suggest that Liolaemus lonquimayensis is a synonym of Liolaemus elongatus. PMID:27920609

  2. Governing the Extractive Sector: The Politics of Globalisation and Copper Policy in Chile

    Directory of Open Access Journals (Sweden)

    Jewellord T. Nem Singh

    2010-09-01

    Full Text Available Chile exhibits an immense continuity in its copper policy and the sector’s reliable output contributes enormously to the tax revenues of the state. Copper in Chile is thus an interesting case because it challenges the presumed failure of neoliberal reforms in Latin America. It does this in a number of different ways. First, the sector is a clear success in terms of its output and contribution to GDP. Second, private capital and foreign direct investment in particular plays a critical role in developing the mining sector. Third, state- owned CODELCO has stood firmly against multinational companies. And fourth, Chile simultaneously exhibits a stability of rules inherited from Pinochet’s neoliberalism; labour relations characterised by conflict and co-optation; and a depoliticised mode of governance marked by copper policy technopols and an indirect link between copper and social policy. This paper argues that the Chilean state under La Concertación government has played an important ‘steering’ role by defusing the various political conflicts, contradictions and tensions in copper policy.

  3. Thermal and lighting perception in four fully glazed office buildings in Santiago, Chile

    Directory of Open Access Journals (Sweden)

    Claudio Vásquez

    2013-12-01

    Full Text Available Corresponding author: Claudio Vásquez, School of Architecture, Catholic University of Chile. 1916 El Comendador str. Providencia, Santiago, ZIP: 7530091, Chile. Tel.: +56 9 92826305; E-mail: clvasque@uc.cl This paper is part of a general research project whose main objective is to establish a baseline for post-occupancy energy consumption and indoor environmental quality for office buildings in Santiago, Chile. This study aims at understanding how architectonical variables relate to, and can even determine, user comfort perception. Thus, one-year continuous monitoring in several floors at four office buildings was performed and seasonal surveys were completed. Survey participants were asked a series of questions regarding spatial orientation and comfort perception in their workspace. The data from the comfort survey and onsite measurements such as season of the year, case study, type of workspace and possibility of an outdoor view from the workstation were contrasted with the components obtained by a Principal Component Analysis (PCA. Three components were selected from the PCA, and three Maps of Perception (MP were produced. These maps were then analyzed and interpreted so as to obtain information on the general perception of thermal and lighting comfort at workspaces within several office buildings in Santiago.

  4. Status of market, regulation and research of genetically modified crops in Chile.

    Science.gov (United States)

    Sánchez, Miguel A; León, Gabriel

    2016-12-25

    Agricultural biotechnology and genetically modified (GM) crops are effective tools to substantially increase productivity, quality, and environmental sustainability in agricultural farming. Furthermore, they may contribute to improving the nutritional content of crops, addressing needs related to public health. Chile has become one of the most important global players for GM seed production for counter-season markets and research purposes. It has a comprehensive regulatory framework to carry out this activity, while at the same time there are numerous regulations from different agencies addressing several aspects related to GM crops. Despite imports of GM food/feed or ingredients for the food industry being allowed without restrictions, Chilean farmers are not using GM seeds for farming purposes because of a lack of clear guidelines. Chile is in a rather contradictory situation about GM crops. The country has invested considerable resources to fund research and development on GM crops, but the lack of clarity in the current regulatory situation precludes the use of such research to develop new products for Chilean farmers. Meanwhile, a larger scientific capacity regarding GM crop research continues to build up in the country. The present study maps and analyses the current regulatory environment for research and production of GM crops in Chile, providing an updated overview of the current status of GM seeds production, research and regulatory issues. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Penguin Bank: A Loa-Trend Hawaiian Volcano

    Science.gov (United States)

    Xu, G.; Blichert-Toft, J.; Clague, D. A.; Cousens, B.; Frey, F. A.; Moore, J. G.

    2007-12-01

    Hawaiian volcanoes along the Hawaiian Ridge from Molokai Island in the northwest to the Big Island in the southeast, define two parallel trends of volcanoes known as the Loa and Kea spatial trends. In general, lavas erupted along these two trends have distinctive geochemical characteristics that have been used to define the spatial distribution of geochemical heterogeneities in the Hawaiian plume (e.g., Abouchami et al., 2005). These geochemical differences are well established for the volcanoes forming the Big Island. The longevity of the Loa- Kea geochemical differences can be assessed by studying East and West Molokai volcanoes and Penguin Bank which form a volcanic ridge perpendicular to the Loa and Kea spatial trends. Previously we showed that East Molokai volcano (~1.5 Ma) is exclusively Kea-like and that West Molokai volcano (~1.8 Ma) includes lavas that are both Loa- and Kea-like (Xu et al., 2005 and 2007).The submarine Penguin Bank (~2.2 Ma), probably an independent volcano constructed west of West Molokai volcano, should be dominantly Loa-like if the systematic Loa and Kea geochemical differences were present at ~2.2 Ma. We have studied 20 samples from Penguin Bank including both submarine and subaerially-erupted lavas recovered by dive and dredging. All lavas are tholeiitic basalt representing shield-stage lavas. Trace element ratios, such as Sr/Nb and Zr/Nb, and isotopic ratios of Sr and Nd clearly are Loa-like. On an ɛNd-ɛHf plot, Penguin Bank lavas fall within the field defined by Mauna Loa lavas. Pb isotopic data lie near the Loa-Kea boundary line defined by Abouchami et al. (2005). In conclusion, we find that from NE to SW, i.e., perpendicular to the Loa and Kea spatial trend, there is a shift from Kea-like East Molokai lavas to Loa-like Penguin Bank lavas with the intermediate West Molokai volcano having lavas with both Loa- and Kea-like geochemical features. Therefore, the Loa and Kea geochemical dichotomy exhibited by Big Island volcanoes

  6. Volcano-hydrothermal energy research at white Island, New Zealand

    International Nuclear Information System (INIS)

    Allis, R.G.

    1994-01-01

    This paper presents the White Island (New Zealand) volcano-hydrothermal research project by the N.Z. DSIR and the Geological Survey of Japan, which is investigating the coupling between magmatic and geothermal systems. The first phase of this investigation is a geophysical survey of the crater floor of the andesite volcano, White Island during 1991/1992, to be followed by drilling from the crater floor into the hydrothermal system. (TEC). 4 figs., 8 refs

  7. Geochemical signatures of tephras from Quaternary Antarctic Peninsula volcanoes

    OpenAIRE

    Kraus,Stefan; Kurbatov,Andrei; Yates,Martin

    2013-01-01

    In the northern Antarctic Peninsula area, at least 12 Late Plelstocene-Holocene volcanic centers could be potential sources of tephra layers in the region. We present unique geochemical fingerprints for ten of these volcanoes using major, trace, rare earth element, and isotope data from 95 samples of tephra and other eruption products. The volcanoes have predominantly basaltic and basaltic andesitic compositions. The Nb/Y ratio proves useful to distinguish between volcanic centers located on ...

  8. Estimates of elastic plate thicknesses beneath large volcanos on Venus

    Science.gov (United States)

    Mcgovern, Patrick J.; Solomon, Sean C.

    1992-01-01

    Megellan radar imaging and topography data are now available for a number of volcanos on Venus greater than 100 km in radius. These data can be examined to reveal evidence of the flexural response of the lithosphere to the volcanic load. On Earth, flexure beneath large hotspot volcanos results in an annual topographic moat that is partially to completely filled in by sedimentation and mass wasting from the volcano's flanks. On Venus, erosion and sediment deposition are considered to be negligible at the resolution of Magellan images. Thus, it may be possible to observe evidence of flexure by the ponding of recent volcanic flows in the moat. We also might expect to find topographic signals from unfilled moats surrounding large volcanos on Venus, although these signals may be partially obscured by regional topography. Also, in the absence of sedimentation, tectonic evidence of deformation around large volcanos should be evident except where buried by very young flows. We use analytic solutions in axisymmetric geometry for deflections and stresses resulting from loading of a plate overlying an inviscid fluid. Solutions for a set of disk loads are superimposed to obtain a solution for a conical volcano. The deflection of the lithosphere produces an annular depression or moat, the extent of which can be estimated by measuring the distance from the volcano's edge to the first zero crossing or to the peak of the flexural arch. Magellan altimetry data records (ARCDRs) from data cycle 1 are processed using the GMT mapping and graphics software to produce topographic contour maps of the volcanos. We then take topographic profiles that cut across the annular and ponded flows seen on the radar images. By comparing the locations of these flows to the predicted moat locations from a range of models, we estimate the elastic plate thickness that best fits the observations, together with the uncertainty in that estimate.

  9. Green Lightning Channels From the Chaiten Volcano in Chile Photographed By Carlos Gutierrez May 2-3, 2008

    Science.gov (United States)

    Few, A. A.

    2013-12-01

    The two photographs containing the green lightning channels appeared on the Boston.com web site (The Big Picture, June 4, 2008). These web photographs were of limited resolution (176 Kb) making the interpretation of the green channels difficult. The agent for Gutierrez, Landov LLC, made available the two photographs as high resolution digital photographs (1.4 Mb and 1.5 Mb) that appear on the poster. Upon close examination of the green channels it is possible to exclude negative discharges or their remnants as being the source of the green channels; negative discharges require white-hot ionization processes at the leading tip of the channel. There are several examples of the white negative channels on the photographs. The green channels might be positive streamers. In thunderstorms positive streamers propagate within the negative charged region of the cloud collecting electrons, which are supplied to the connected negative discharge channel, hence they are not observed in thunderstorms. They can be detected and mapped inside the thunderstorm from observations of their electromagnetic radiations. Positive streamers are cooler than negative discharges because electrons are convergent on the leading tip of the positive streamer maintaining its conductivity. For the negative leading tips the electrons are divergent and new electrons must be generated by hot ionization processes. A close examination reveals that the green channels track the edge of the ash cloud, which if a positive streamer would indicate a negative surface charge on the cloud. Most likely the green color results from excited oxygen atoms returning to the ground state and emitting a green photon. This is the process that produces the green aurora, and if this produces green lightning, it places several constraints on the conditions of the channel. The two photographs below are selected clips from the much larger photographs; these show the green lightning channels.

  10. Dos edificios públicos a base de tierra en Chile

    Directory of Open Access Journals (Sweden)

    Pereira, Hugo

    1986-02-01

    Full Text Available Two works in Chile are reported: The House of the Culture in La Florida (Santiago and the Botalcura Concentred School in the Vlllth Zone. Both constructions have as common characteristic to be built with adobe and wooden girders, to present a certain continuity in the adapted criteria of desing -both from Architect Hugo Pereira- and to be newly constructed buildings, even partialy in construction. The fact that there are spaces with appropriate light and height for public use, so as the circumstance that the part which waas being constructed just at the moment of the great seism in Chile (February 1985 had and excelent behaviour, makes these works interesting to be published.Se presentan dos realizaciones en Chile: la Casa de la Cultura, en la barriada La Florida (Santiago y la Escuela Concentrada de Botalcura, en la VIII Región. Ambas construcciones tienen en común el haberse realizado a base de adobe y cerchas de madera, el presentar una cierta continuidad en los criterios de diseño adoptados, en ambas ha participado el Arquitecto Hugo Pereira, y ser edificios recién construidos, incluso parcialmente en construcción. El hecho de tratarse de espacios con luces y alturas propias de construcciones para uso público, así como la circunstancia de que la parte construida de la Casa de la Cultura en el momento del último gran sismo en Chile (marzo 1985, presentase un excelente comportamiento, son hechos que hacen especialmente interesante la publicación de estas realizaciones.

  11. Recent Seismicity in the Ceboruco Volcano, Western Mexico

    Science.gov (United States)

    Nunez, D.; Chávez-Méndez, M. I.; Nuñez-Cornu, F. J.; Sandoval, J. M.; Rodriguez-Ayala, N. A.; Trejo-Gomez, E.

    2017-12-01

    The Ceboruco volcano is the largest (2280 m.a.s.l) of several volcanoes along the Tepic-Zacoalco rift zone in Nayarit state (Mexico). During the last 1000 years, this volcano had effusive-explosive episodes with eight eruptions providing an average of one eruption each 125 years. Since the last eruption occurred in 1870, 147 years ago, a new eruption likelihood is really high and dangerous due to nearby population centers, important roads and lifelines that traverse the volcano's slopes. This hazards indicates the importance of monitoring the seismicity associated with the Ceboruco volcano whose ongoing activity is evidenced by fumaroles and earthquakes. During 2003 and 2008, this region was registered by just one Lennartz Marslite seismograph featuring a Lennartz Le3D sensor (1 Hz) [Rodríguez Uribe et al. (2013)] where they observed that seismicity rates and stresses appear to be increasing indicating higher levels of activity within the volcano. Until July 2017, a semi-permanent network with three Taurus (Nanometrics) and one Q330 Quanterra (Kinemetrics) digitizers with Lennartz 3Dlite sensors of 1 Hz natural frequency was registering in the area. In this study, we present the most recent seismicity obtained by the semi-permanent network and a temporary network of 21 Obsidians 4X and 8X (Kinemetrics) covering an area of 16 km x 16 km with one station every 2.5-3 km recording from November 2016 to July 2017.

  12. Silencio y memoria: Nocturno de Chile

    Directory of Open Access Journals (Sweden)

    Pedro Iniesta Ruiz

    2016-12-01

    Full Text Available El presente estudio, sostenido por el Trabajo de Fin de Grado Representación y ficción: Nocturno de Chile y Sostiene Pereira (2015, se introduce en la construcción literaria articulada en la obra Nocturno de Chile, de Roberto Bolaño, examinando y evaluando sus fronteras, fronteras que resultan tan movedizas como las de cualquier construcción inserta en el marco de la ficción. Las implicaciones históricas y políticas del relato hacen que su impronta testimonial cobre una fuerza inusitada, y nociones como la memoria, la violencia o el silencio ayudan a vertebrar una obra de arte verbal que logra, en el decurso de su propia narración, asediar al lector con las angustiosas imágenes de un pasado hecho presente en el camino de un tiempo político que se subyuga a la propia creación artística.

  13. Evaluation of Earthquake-Induced Effects on Neighbouring Faults and Volcanoes: Application to the 2016 Pedernales Earthquake

    Science.gov (United States)

    Bejar, M.; Alvarez Gomez, J. A.; Staller, A.; Luna, M. P.; Perez Lopez, R.; Monserrat, O.; Chunga, K.; Herrera, G.; Jordá, L.; Lima, A.; Martínez-Díaz, J. J.

    2017-12-01

    It has long been recognized that earthquakes change the stress in the upper crust around the fault rupture and can influence the short-term behaviour of neighbouring faults and volcanoes. Rapid estimates of these stress changes can provide the authorities managing the post-disaster situation with a useful tool to identify and monitor potential threads and to update the estimates of seismic and volcanic hazard in a region. Space geodesy is now routinely used following an earthquake to image the displacement of the ground and estimate the rupture geometry and the distribution of slip. Using the obtained source model, it is possible to evaluate the remaining moment deficit and to infer the stress changes on nearby faults and volcanoes produced by the earthquake, which can be used to identify which faults and volcanoes are brought closer to failure or activation. Although these procedures are commonly used today, the transference of these results to the authorities managing the post-disaster situation is not straightforward and thus its usefulness is reduced in practice. Here we propose a methodology to evaluate the potential influence of an earthquake on nearby faults and volcanoes and create easy-to-understand maps for decision-making support after an earthquake. We apply this methodology to the Mw 7.8, 2016 Ecuador earthquake. Using Sentinel-1 SAR and continuous GPS data, we measure the coseismic ground deformation and estimate the distribution of slip. Then we use this model to evaluate the moment deficit on the subduction interface and changes of stress on the surrounding faults and volcanoes. The results are compared with the seismic and volcanic events that have occurred after the earthquake. We discuss potential and limits of the methodology and the lessons learnt from discussion with local authorities.

  14. Interferometric synthetic aperture radar study of Okmok volcano, Alaska, 1992-2003: Magma supply dynamics and postemplacement lava flow deformation

    Science.gov (United States)

    Lu, Z.; Masterlark, Timothy; Dzurisin, Daniel

    2005-01-01

    Okmok volcano, located in the central Aleutian arc, Alaska, is a dominantly basaltic complex topped with a 10-km-wide caldera that formed circa 2.05 ka. Okmok erupted several times during the 20th century, most recently in 1997; eruptions in 1945, 1958, and 1997 produced lava flows within the caldera. We used 80 interferometric synthetic aperture radar (InSAR) images (interferograms) to study transient deformation of the volcano before, during, and after the 1997 eruption. Point source models suggest that a magma reservoir at a depth of 3.2 km below sea level, located beneath the center of the caldera and about 5 km northeast of the 1997 vent, is responsible for observed volcano-wide deformation. The preeruption uplift rate decreased from about 10 cm yr−1 during 1992–1993 to 2 ∼ 3 cm yr−1 during 1993–1995 and then to about −1 ∼ −2 cm yr−1 during 1995–1996. The posteruption inflation rate generally decreased with time during 1997–2001, but increased significantly during 2001–2003. By the summer of 2003, 30 ∼ 60% of the magma volume lost from the reservoir in the 1997 eruption had been replenished. Interferograms for periods before the 1997 eruption indicate consistent subsidence of the surface of the 1958 lava flows, most likely due to thermal contraction. Interferograms for periods after the eruption suggest at least four distinct deformation processes: (1) volcano-wide inflation due to replenishment of the shallow magma reservoir, (2) subsidence of the 1997 lava flows, most likely due to thermal contraction, (3) deformation of the 1958 lava flows due to loading by the 1997 flows, and (4) continuing subsidence of 1958 lava flows buried beneath 1997 flows. Our results provide insights into the postemplacement behavior of lava flows and have cautionary implications for the interpretation of inflation patterns at active volcanoes.

  15. Petrologic insights into basaltic volcanism at historically active Hawaiian volcanoes: Chapter 6 in Characteristics of Hawaiian volcanoes

    Science.gov (United States)

    Helz, Rosalind L.; Clague, David A.; Sisson, Thomas W.; Thornber, Carl R.; Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.

    2014-01-01

    Study of the petrology of Hawaiian volcanoes, in particular the historically active volcanoes on the Island of Hawai‘i, has long been of worldwide scientific interest. When Dr. Thomas A. Jaggar, Jr., established the Hawaiian Volcano Observatory (HVO) in 1912, detailed observations on basaltic activity at Kīlauea and Mauna Loa volcanoes increased dramatically. The period from 1912 to 1958 saw a gradual increase in the collection and analysis of samples from the historical eruptions of Kīlauea and Mauna Loa and development of the concepts needed to evaluate them. In a classic 1955 paper, Howard Powers introduced the concepts of magnesia variation diagrams, to display basaltic compositions, and olivine-control lines, to distinguish between possibly comagmatic and clearly distinct basaltic lineages. In particular, he and others recognized that Kīlauea and Mauna Loa basalts must have different sources.

  16. The diversity of mud volcanoes in the landscape of Azerbaijan

    Science.gov (United States)

    Rashidov, Tofig

    2014-05-01

    As the natural phenomenon the mud volcanism (mud volcanoes) of Azerbaijan are known from the ancient times. The historical records describing them are since V century. More detail study of this natural phenomenon had started in the second half of XIX century. The term "mud volcano" (or "mud hill") had been given by academician H.W. Abich (1863), more exactly defining this natural phenomenon. All the previous definitions did not give such clear and capacious explanation of it. In comparison with magmatic volcanoes, globally the mud ones are restricted in distribution; they mainly locate within the Alpine-Himalayan, Pacific and Central Asian mobile belts, in more than 30 countries (Columbia, Trinidad Island, Italy, Romania, Ukraine, Georgia, Azerbaijan, Turkmenistan, Iran, Pakistan, Indonesia, Burma, Malaysia, etc.). Besides it, the zones of mud volcanoes development are corresponded to zones of marine accretionary prisms' development. For example, the South-Caspian depression, Barbados Island, Cascadia (N.America), Costa-Rica, Panama, Japan trench. Onshore it is Indonesia, Japan, and Trinidad, Taiwan. The mud volcanism with non-accretionary conditions includes the areas of Black Sea, Alboran Sea, the Gulf of Mexico (Louisiana coast), Salton Sea. But new investigations reveal more new mud volcanoes and in places which were not considered earlier as the traditional places of mud volcanoes development (e.g. West Nile Rive delta). Azerbaijan is the classic region of mud volcanoes development. From over 800 world mud volcanoes there are about 400 onshore and within the South-Caspian basin, which includes the territory of East Azerbaijan (the regions of Shemakha-Gobustan and Low-Kura River, Absheron peninsula), adjacent water area of South Caspian (Baku and Absheron archipelagoes) and SW Turkmenistan and represents an area of great downwarping with thick (over 25 km) sedimentary series. Generally, in the modern relief the mud volcanoes represent more or less large uplifts

  17. Application of Earthquake Subspace Detectors at Kilauea and Mauna Loa Volcanoes, Hawai`i

    Science.gov (United States)

    Okubo, P.; Benz, H.; Yeck, W.

    2016-12-01

    Recent studies have demonstrated the capabilities of earthquake subspace detectors for detailed cataloging and tracking of seismicity in a number of regions and settings. We are exploring the application of subspace detectors at the United States Geological Survey's Hawaiian Volcano Observatory (HVO) to analyze seismicity at Kilauea and Mauna Loa volcanoes. Elevated levels of microseismicity and occasional swarms of earthquakes associated with active volcanism here present cataloging challenges due the sheer numbers of earthquakes and an intrinsically low signal-to-noise environment featuring oceanic microseism and volcanic tremor in the ambient seismic background. With high-quality continuous recording of seismic data at HVO, we apply subspace detectors (Harris and Dodge, 2011, Bull. Seismol. Soc. Am., doi: 10.1785/0120100103) during intervals of noteworthy seismicity. Waveform templates are drawn from Magnitude 2 and larger earthquakes within clusters of earthquakes cataloged in the HVO seismic database. At Kilauea, we focus on seismic swarms in the summit caldera region where, despite continuing eruptions from vents in the summit region and in the east rift zone, geodetic measurements reflect a relatively inflated volcanic state. We also focus on seismicity beneath and adjacent to Mauna Loa's summit caldera that appears to be associated with geodetic expressions of gradual volcanic inflation, and where precursory seismicity clustered prior to both Mauna Loa's most recent eruptions in 1975 and 1984. We recover several times more earthquakes with the subspace detectors - down to roughly 2 magnitude units below the templates, based on relative amplitudes - compared to the numbers of cataloged earthquakes. The increased numbers of detected earthquakes in these clusters, and the ability to associate and locate them, allow us to infer details of the spatial and temporal distributions and possible variations in stresses within these key regions of the volcanoes.

  18. Felsic maar-diatreme volcanoes: a review

    Science.gov (United States)

    Ross, Pierre-Simon; Carrasco Núñez, Gerardo; Hayman, Patrick

    2017-02-01

    Felsic maar-diatreme volcanoes host major ore deposits but have been largely ignored in the volcanology literature, especially for the diatreme portion of the system. Here, we use two Mexican tuff rings as analogs for the maar ejecta ring, new observations from one diatreme, and the economic geology literature on four other mineralized felsic maar-diatremes to produce an integrated picture of this type of volcano. The ejecta rings are up to 50 m+ thick and extend laterally up to ˜1.5 km from the crater edge. In two Mexican examples, the lower part of the ejecta ring is dominated by pyroclastic surge deposits with abundant lithic clasts (up to 80% at Hoya de Estrada). These deposits display low-angle cross-bedding, dune bedforms, undulating beds, channels, bomb sags, and accretionary lapilli and are interpreted as phreatomagmatic. Rhyolitic juvenile clasts at Tepexitl have only 0-25% vesicles in this portion of the ring. The upper parts of the ejecta ring sequences in the Mexican examples have a different character: lithic clasts can be less abundant, the grain size is typically coarser, and the juvenile clasts can be different in character (with some more vesicular fragments). Fragmentation was probably shallower at this stage. The post-eruptive maar crater infill is known at Wau and consists of reworked pyroclastic deposits as well as lacustrine and other sediments. Underneath are bedded upper diatreme deposits, interpreted as pyroclastic surge and fall deposits. The upper diatreme and post-eruptive crater deposits have dips larger than 30° at Wau, with approximately centroclinal attitudes. At still lower structural levels, the diatreme pyroclastic infill is largely unbedded; Montana Tunnels and Kelian are good examples of this. At Cerro de Pasco, the pyroclastic infill seems bedded despite about 500 m of post-eruptive erosion relative to the pre-eruptive surface. The contact between the country rocks and the diatreme is sometimes characterized by country rock

  19. Analýza obchodných vzťahov medzi EU a Chile

    OpenAIRE

    Chabová, Zuzana

    2011-01-01

    The aim of my bachelor thesis is to particularly charakterize Chile's economy and to analyze its position in international trade. The main part of my whole work is the analysis of business relationship between European Union and Chile, which I also describe in point of law. The work has five main chapters. The first chapter describes the economical situation of Chile. The second chapter is concerned with Chile's whole foreign trade. The third chapter analyze Chile's foreign trade legally thro...

  20. The Powell Volcano Remote Sensing Working Group Overview

    Science.gov (United States)

    Reath, K.; Pritchard, M. E.; Poland, M. P.; Wessels, R. L.; Biggs, J.; Carn, S. A.; Griswold, J. P.; Ogburn, S. E.; Wright, R.; Lundgren, P.; Andrews, B. J.; Wauthier, C.; Lopez, T.; Vaughan, R. G.; Rumpf, M. E.; Webley, P. W.; Loughlin, S.; Meyer, F. J.; Pavolonis, M. J.

    2017-12-01

    Hazards from volcanic eruptions pose risks to the lives and livelihood of local populations, with potential global impacts to businesses, agriculture, and air travel. The 2015 Global Assessment of Risk report notes that 800 million people are estimated to live within 100 km of 1400 subaerial volcanoes identified as having eruption potential. However, only 55% of these volcanoes have any type of ground-based monitoring. The only methods currently available to monitor these unmonitored volcanoes are space-based systems that provide a global view. However, with the explosion of data techniques and sensors currently available, taking full advantage of these resources can be challenging. The USGS Powell Center Volcano Remote Sensing Working Group is working with many partners to optimize satellite resources for global detection of volcanic unrest and assessment of potential eruption hazards. In this presentation we will describe our efforts to: 1) work with space agencies to target acquisitions from the international constellation of satellites to collect the right types of data at volcanoes with forecasting potential; 2) collaborate with the scientific community to develop databases of remotely acquired observations of volcanic thermal, degassing, and deformation signals to facilitate change detection and assess how these changes are (or are not) related to eruption; and 3) improve usage of satellite observations by end users at volcano observatories that report to their respective governments. Currently, the group has developed time series plots for 48 Latin American volcanoes that incorporate variations in thermal, degassing, and deformation readings over time. These are compared against eruption timing and ground-based data provided by the Smithsonian Institute Global Volcanism Program. Distinct patterns in unrest and eruption are observed at different volcanoes, illustrating the difficulty in developing generalizations, but highlighting the power of remote sensing

  1. Volatile Element Fluxes at Copahue Volcano, Argentina

    Science.gov (United States)

    Varekamp, J. C.

    2002-05-01

    Copahue volcano has a crater lake and acid hot springs that discharge into the Rio Agrio river system. These fluids are very concentrated (up to 6 % sulfate), rich in rock-forming elements (up to 2000 ppm Mg) and small spheres of native sulfur float in the crater lake. The stable isotope composition of the waters (delta 18O =-2.1 to + 3.6 per mille; delta D = -49 to -26 per mille) indicates that the hot spring waters are at their most concentrated about 70% volcanic brine and 30 % glacial meltwater. The crater lake waters have similar mixing proportions but added isotope effects from intense evaporation. Further dilution of the waters in the Rio Agrio gives values closer to local meteoric waters (delta 18O = -11 per mille; delta D = -77 per mille), whereas evaporation in closed ponds led to very heavy water (up to delta 18O = +12 per mille). The delta 34S value of dissolved sulfate is +14.2 per mille, whereas the native sulfur has values of -8.2 to -10.5 per mille. The heavy sulfate probably formed when SO2 disproportionated into bisulfate and native sulfur at about 300 C. We measured the sulfate fluxes in the Rio Agrio, which ranged from 20-40 kilotons S/year. The whole system was releasing sulfur at an equivalent rate of about 250-650 tons SO2/day. From the river flux sulfur values and the stochiometry of the disproportionation reaction we calculated the rate of liquid sulfur storage inside the volcano (6000 m3/year). During the eruptions of 1995/2000, large amounts of that stored liquid sulfur were ejected as pyroclastic sulfur. The calculated rate of rock dissolution (from rock- forming element fluxes in the Rio Agrio) suggests that the void space generated by rock dissolution is largely filled by native sulfur and silica. The S/Cl ratio in the hydrothermal fluids is about 2, whereas glass inclusions have S/Cl = 0.2, indicating the strong preferential degassing of sulfur.

  2. Magma Dynamics in Dome-Building Volcanoes

    Science.gov (United States)

    Kendrick, J. E.; Lavallée, Y.; Hornby, A. J.; Schaefer, L. N.; Oommen, T.; Di Toro, G.; Hirose, T.

    2014-12-01

    The frequent and, as yet, unpredictable transition from effusive to explosive volcanic behaviour is common to active composite volcanoes, yet our understanding of the processes which control this evolution is poor. The rheology of magma, dictated by its composition, porosity and crystal content, is integral to eruption behaviour and during ascent magma behaves in an increasingly rock-like manner. This behaviour, on short timescales in the upper conduit, provides exceptionally dynamic conditions that favour strain localisation and failure. Seismicity released by this process can be mimicked by damage accumulation that releases acoustic signals on the laboratory scale, showing that the failure of magma is intrinsically strain-rate dependent. This character aids the development of shear zones in the conduit, which commonly fracture seismogenically, producing fault surfaces that control the last hundreds of meters of ascent by frictional slip. High-velocity rotary shear (HVR) experiments demonstrate that at ambient temperatures, gouge behaves according to Byerlee's rule at low slip velocities. At rock-rock interfaces, mechanical work induces comminution of asperities and heating which, if sufficient, may induce melting and formation of pseudotachylyte. The viscosity of the melt, so generated, controls the subsequent lubrication or resistance to slip along the fault plane thanks to non-Newtonian suspension rheology. The bulk composition, mineralogy and glass content of the magma all influence frictional behaviour, which supersedes buoyancy as the controlling factor in magma ascent. In the conduit of dome-building volcanoes, the fracture and slip processes are further complicated: slip-rate along the conduit margin fluctuates. The shear-thinning frictional melt yields a tendency for extremely unstable slip thanks to its pivotal position with regard to the glass transition. This thermo-kinetic transition bestows the viscoelastic melt with the ability to either flow or

  3. Volcano surveillance by ACR silver fox

    Science.gov (United States)

    Patterson, M.C.L.; Mulligair, A.; Douglas, J.; Robinson, J.; Pallister, J.S.

    2005-01-01

    Recent growth in the business of unmanned air vehicles (UAVs) both in the US and abroad has improved their overall capability, resulting in a reduction in cost, greater reliability and adoption into areas where they had previously not been considered. Uses in coastal and border patrol, forestry and agriculture have recently been evaluated in an effort to expand the observed area and reduce surveillance and reconnaissance costs for information gathering. The scientific community has both contributed and benefited greatly in this development. A larger suite of light-weight miniaturized sensors now exists for a range of applications which in turn has led to an increase in the gathering of information from these autonomous vehicles. In October 2004 the first eruption of Mount St Helens since 1986 caused tremendous interest amoUg people worldwide. Volcanologists at the U.S. Geological Survey rapidly ramped up the level of monitoring using a variety of ground-based sensors deployed in the crater and on the flanks of the volcano using manned helicopters. In order to develop additional unmanned sensing methods that can be used in potentially hazardous and low visibility conditions, a UAV experiment was conducted during the ongoing eruption early in November. The Silver Fox UAV was flown over and inside the crater to perform routine observation and data gathering, thereby demonstrating a technology that could reduce physical risk to scientists and other field operatives. It was demonstrated that UAVs can be flown autonomously at an active volcano and can deliver real time data to a remote location. Although still relatively limited in extent, these initial flights provided information on volcanic activity and thermal conditions within the crater and at the new (2004) lava dome. The flights demonstrated that readily available visual and infrared video sensors mounted in a small and relatively low-cost aerial platform can provide useful data on volcanic phenomena. This was

  4. El Parque Portal Bicentenario en Santiago de Chile / Portal Bicentennial Park in Santiago de Chile

    Directory of Open Access Journals (Sweden)

    Beach Lobos, Myriam;

    2007-06-01

    Full Text Available Se presenta los principios que orientaron el diseño del Parque Portal Bicentenario, un parque de 50 hás. que será el eje principal de la nueva urbanización “Ciudad Parque Bicentenario”, actualmente en construcción en los terrenos del ex aeropuerto de Los Cerrillos en Santiago de Chile.The following text was submitted to the Architecture Competition together with the project drawings. It presents the principles that leaded the design. The 123 acres park will be the main axis of a new urban development in Santiago “Ciudad Parque Bicentenario” at present under construction on the area occupied by the former Cerrillos Airport, Santiago de Chile.

  5. Studies to Control Endemic Typhoid Fever in Chile

    Science.gov (United States)

    1983-01-30

    Bol. Inst. Bacteriol. Chile 1976; 18:33-37. 30. Escaff, M, Urbina, A, Mary, J. Contaminacion de repollos regados con aguas servidas. Agricultura...Tecnica 1979; 39:59-62. - 31. Lobos, H, Greive, R, Quijada, M, Brandt, H. Pesquisa del genero Vibrio en aguas servidas. Bol. Inst. Bact. Chile 1974; 16:40...REPORT #2 0") STUDIES TO CONTROL ENDEMIC TYPHOID N FEVER IN CHILE 0) ANNUAL REPORT U’ Contract Period 1/1/82-12/31/82 • I REPORT PREPARED BY: L

  6. [Ecology and health in Chile: present and future development].

    Science.gov (United States)

    Oyarzún, M

    1997-09-01

    In response to the progressive environmental deterioration, the Ecological Society of America has made a proposal, called "Sustainable Biosphere Initiative", to do research, teaching and decision making processes on biodiversity, global change and the effects of human activities on environment. The goal of appropriate environmental protection and welfare for mankind includes health and quality of life. Presently, Chile faces a number of environmental problems such as pollution, excessive urban growth, loss of agricultural areas, disposal of solid waste and species extinction. The lack of education and information in Chile, on these problems, is worrisome. The role of universities to overcome this deficit should be crucial in the future sustainable development of Chile.

  7. Business continuity

    International Nuclear Information System (INIS)

    Breunhoelder, Gert

    2002-01-01

    This presentation deals with the following keypoints: Information Technology (IT) Business Continuity and Recovery essential for any business; lessons learned after Sept. 11 event; Detailed planning, redundancy and testing being the key elements for probability estimation of disasters

  8. Continuous tokamaks

    International Nuclear Information System (INIS)

    Peng, Y.K.M.

    1978-04-01

    A tokamak configuration is proposed that permits the rapid replacement of a plasma discharge in a ''burn'' chamber by another one in a time scale much shorter than the elementary thermal time constant of the chamber first wall. With respect to the chamber, the effective duty cycle factor can thus be made arbitrarily close to unity minimizing the cyclic thermal stress in the first wall. At least one plasma discharge always exists in the new tokamak configuration, hence, a continuous tokamak. By incorporating adiabatic toroidal compression, configurations of continuous tokamak compressors are introduced. To operate continuous tokamaks, it is necessary to introduce the concept of mixed poloidal field coils, which spatially groups all the poloidal field coils into three sets, all contributing simultaneously to inducing the plasma current and maintaining the proper plasma shape and position. Preliminary numerical calculations of axisymmetric MHD equilibria in continuous tokamaks indicate the feasibility of their continued plasma operation. Advanced concepts of continuous tokamaks to reduce the topological complexity and to allow the burn plasma aspect ratio to decrease for increased beta are then suggested

  9. Log evaluation of sub-bituminous coals in Magallanes, Chile

    International Nuclear Information System (INIS)

    Weltz, L.S.

    1976-01-01

    In coal exploration a drilling program is normally used for coal inquest through core analysis, with a high cost and operating time. However, in many cases, there is poor cores recovery due to operating procedures and/or formation conditions which leads to the determination of parameters non-representative of the coal seam. The cost and operating time can be minimized through the use of logs which also represent a continuous and in situ sampling. In the case of sub-bituminous coals, the analysis through logs is more complex due to the high content of clay, which masks the presence of water. This paper describes the analysis of sub-bituminous coals in Magallanes-Chile. The main coal seam components are: coal, clay, secondary quartz and water. An interpretation system using the density log, gamma ray, sonic and microlog, based on rho/sub B/-GR and rho/sub B/--Δ/sub T/ cross plots, permits to know the weight percentages of the following elements: total carbon, ash, moisture, which form the main local coal parameters. Empirical relationships permit us to obtain also the heating value and an estimate strength index to elastic-dynamic forces. The results obtained agree within 3 percent with the Laboratory cores analysis. The method is processed through a sequence of simple computer programs for IBM-360

  10. Avian Influenza in wild birds from Chile, 2007-2009.

    Science.gov (United States)

    Mathieu, Christian; Moreno, Valentina; Pedersen, Janice; Jeria, Julissa; Agredo, Michel; Gutiérrez, Cristian; García, Alfonso; Vásquez, Marcela; Avalos, Patricia; Retamal, Patricio

    2015-03-02

    Aquatic and migratory birds, the main reservoir hosts of avian influenza viruses including those with high pathogenic potential, are the wildlife species with the highest risk for viral dissemination across countries and continents. In 2002, the Chilean poultry industry was affected with a highly pathogenic avian influenza strain, which created economic loss and triggered the establishment of a surveillance program in wild birds. This effort consisted of periodic samplings of sick or suspicious animals found along the coast and analyses with standardized techniques for detection of influenza A virus. The aim of this work is to report the detection of three avian influenza strains (H13N2, H5N9, H13N9) in gulls from Chile between 2007-2009, which nucleotide sequences showed highest similitudes to viruses detected in wild birds from North America. These results suggest a dissemination route for influenza viruses along the coasts of Americas. Migratory and synanthropic behaviors of birds included in this study support continued monitoring of avian influenza viruses isolated from wild birds in The Americas and the establishment of biosecurity practices in farms. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Cultural experiences of immigrant nurses at two hospitals in Chile

    Directory of Open Access Journals (Sweden)

    Gabriel Rodríguez

    2014-04-01

    Full Text Available OBJECTIVE: to explore the cultural experiences of nurses who immigrated to Chile. The study´s theoretical framework was the Purnell Model for Cultural Competence.METHOD: Leininger's Observation-Participation-Reflection method was developed at two hospitals in the city of Santiago, and ethnographic interviews were held with 15 immigrant nurses.RESULTS: among Purnell's 12 domains, the following were identified: Overview/heritage, Communication, Workforce issues, Family roles and organization, Biocultural ecology and Health-care practices. The difficulties were related to the language and its semantic meaning, the new responsibilities and the difficult relationship with colleagues. "In search of better horizons - the decision to immigrate", "Gaining confidence and establishing a support network - employability and professional performance" and "Seeking for people´s acceptance - professional adaptation in a new cultural scenario" are cultural themes that represent their experiences.CONCLUSIONS: the competence to offer cultural care demands the development of public policies and continuing education programs at health institutions, specifically focused on immigrant nurses.

  12. Illegal fishing and territorial user rights in Chile.

    Science.gov (United States)

    Oyanedel, Rodrigo; Keim, Andres; Castilla, Juan Carlos; Gelcich, Stefan

    2017-11-07

    Illegal fishing poses a major threat to conservation of marine resources worldwide. However, there is still limited empirical research that quantifies illegal catch levels. We used the randomized response technique to estimate the proportion of divers and the quantities of loco (Concholepas concholepas) they extracted illegally. Loco have been managed for the past 17 years through a territorial user rights for fisheries system (TURFs) in Chile. Illegal fishing of loco was widespread within the TURFs system. Official reported landings (i.e., legal landings) accounted for 14-30% of the total loco extraction. Our estimates suggest that ignoring the magnitude of illegal fishing and considering only official landing statistics may lead to false conclusions about the status and trends of a TURFs managed fishery. We found evidence of fisher associations authorizing their members to poach inside TURFs, highlighting the need to design TURFs systems so that government agencies and fishers' incentives and objectives align through continuous adaptation. Government support for enforcement is a key element for the TURFs system to secure the rights that are in place. © 2017 Society for Conservation Biology.

  13. A search for the volcanomagnetic signal at Deception volcano (South Shetland I., Antarctica

    Directory of Open Access Journals (Sweden)

    J. M. Ibáñez

    1997-06-01

    Full Text Available After the increase in seismic activity detected during the 1991-1992 summer survey at Deception Island, the continuous measurement of total magnetic intensity was included among the different techniques used to monitor this active volcano. The Polish geomagnetic observatory Arctowski, located on King George Island, served as a reference station, and changes in the differences between the daily mean values at both stations were interpreted as indicators of volcanomagnetic effects at Deception. A magnetic station in continuous recording mode was also installed during the 1993-1994 and 1994-1995 surveys. During the latter, a second magnetometer was deployed on Deception Island, and a third one in the vicinity of the Spanish Antarctic Station on Livingston Island (at a distance of 35 km and was used as a reference station. The results from the first survey suggest that a small magma injection, responsible for the seismic re-activation, could produce a volcanomagnetic effect, detected as a slight change in the difference between Deception and Arctowski. On the other hand, a long term variation starting at that moment seems to indicate a thermomagnetic effect. However the short register period of only two stations do not allow the sources to be modelled. The future deployment of a magnetic array during the austral summer surveys, throughout the volcano, and of a permanent geomagnetic observatory at Livingston I. is aimed at further observations of magnetic transients of volcanic origin at Deception Island.

  14. SUBMARINE VOLCANO CHARACTERISTICS IN SABANG WATERS

    Directory of Open Access Journals (Sweden)

    Hananto Kurnio

    2017-07-01

    Full Text Available The aim of the study is to understand the characteristics of a volcano occurred in marine environment, as Weh Island where Sabang City located is still demonstrated its volcanic cone morphology either through satellite imagery or bathymetric map. Methods used were marine geology, marine geophysics and oceanography. Results show that surface volcanism (sea depth less than 50 m take place as fumaroles, solfataras, hot ground, hot spring, hot mud pool and alteration in the vicinities of seafloor and coastal area vents. Seismic records also showed acoustic turbidity in the sea water column due to gas bubblings produced by seafloor fumaroles. Geochemical analyses show that seafloor samples in the vicinities of active and non-active fumarole vent are abundances with rare earth elements (REE. These were interpreted that the fumarole bring along REE through its gases and deposited on the surrounding seafloor surface. Co-existence between active fault of Sumatra and current volcanism produce hydrothermal mineralization in fault zone as observed in Serui and Pria Laot-middle of Weh Island which both are controlled by normal faults and graben.

  15. Energy budget of the volcano Stromboli, Italy

    Science.gov (United States)

    Mcgetchin, T. R.; Chouet, B. A.

    1979-01-01

    The results of the analyses of movies of eruptions at Stromboli, Italy, and other available data are used to discuss the question of its energy partitioning among various energy transport mechanisms. Energy is transported to the surface from active volcanoes in at least eight modes, viz. conduction (and convection) of the heat through the surface, radiative heat transfer from the vent, acoustical radiation in blast and jet noise, seismic radiation, thermal energy of ejected particles, kinetic energy of ejected particles, thermal energy of ejected gas, and kinetic energy of ejected gas. Estimated values of energy flux from Stromboli by these eight mechanisms are tabulated. The energy budget of Stromboli in its normal mode of activity appears to be dominated by heat conduction (and convection) through the ground surface. Heat carried by eruption gases is the most important of the other energy transfer modes. Radiated heat from the open vent and heat carried by ejected lava particles also contribute to the total flux, while seismic energy accounts for about 0.5% of the total. All other modes are trivial by comparison.

  16. Geomorphological classification of post-caldera volcanoes in the Buyan-Bratan caldera, North Bali, Indonesia

    Science.gov (United States)

    Okuno, Mitsuru; Harijoko, Agung; Wayan Warmada, I.; Watanabe, Koichiro; Nakamura, Toshio; Taguchi, Sachihiro; Kobayashi, Tetsuo

    2017-12-01

    A landform of the post-caldera volcanoes (Lesung, Tapak, Sengayang, Pohen, and Adeng) in the Buyan-Bratan caldera on the island of Bali, Indonesia can be classified by topographic interpretation. The Tapak volcano has three craters, aligned from north to south. Lava effused from the central crater has flowed downward to the northwest, separating the Tamblingan and Buyan Lakes. This lava also covers the tip of the lava flow from the Lesung volcano. Therefore, it is a product of the latest post-caldera volcano eruption. The Lesung volcano also has two craters, with a gully developing on the pyroclastic cone from the northern slope to the western slope. Lava from the south crater has flowed down the western flank, beyond the caldera rim. Lava distributed on the eastern side from the south also surrounds the Sengayang volcano. The Adeng volcano is surrounded by debris avalanche deposits from the Pohen volcano. Based on these topographic relationships, Sengayang volcano appears to be the oldest of the post-caldera volcanoes, followed by the Adeng, Pohen, Lesung, and Tapak volcanoes. Coarse-grained scoria falls around this area are intercalated with two foreign tephras: the Samalas tephra (1257 A.D.) from Lombok Island and the Penelokan tephra (ca. 5.5 kBP) from the Batur caldera. The source of these scoria falls is estimated to be either the Tapak or Lesung volcano, implying that at least two volcanoes have erupted during the Holocene period.

  17. Los valores del urbanismo en Chile

    Directory of Open Access Journals (Sweden)

    Waldo López Moya

    2005-07-01

    Full Text Available En el mes de junio de 2004 fue presentado al Senado de Chile un proyecto de ley destinado a modificar la Ley General de Urbanismo y Construcciones (LGUC, con el fin de adecuarla para permitir la formación y edificación de «áreas urbanas condicionadas» (AUC. Esto es, conjuntos residenciales urbanos, construidos fuera del límite urbano convencional. Unos, en áreas rurales ubicadas inmediatamente adyacentes al mismo, llamadas «áreas de extensión urbana condicionada» (AEUC, y otros, ubicados en áreas rurales segregadas, denominadas «áreas de desarrollo urbano condicionado» (ADUC.

  18. Subduction zone guided waves in Northern Chile

    Science.gov (United States)

    Garth, Thomas; Rietbrock, Andreas

    2016-04-01

    Guided wave dispersion is observed in subduction zones as high frequency energy is retained and delayed by low velocity structure in the subducting slab, while lower frequency energy is able to travel at the faster velocities associated with the surrounding mantle material. As subduction zone guided waves spend longer interacting with the low velocity structure of the slab than any other seismic phase, they have a unique capability to resolve these low velocity structures. In Northern Chile, guided wave arrivals are clearly observed on two stations in the Chilean fore-arc on permanent stations of the IPOC network. High frequency (> 5 Hz) P-wave arrivals are delayed by approximately 2 seconds compared to the low frequency (young subducting lithosphere also has the potential to carry much larger amounts of water to the mantle than has previously been appreciated.

  19. Licancabur Volcano, Bolivia and life in the Atacama: Environmental physics and analogies to Mars

    Science.gov (United States)

    Hock, Andrew Nelson

    Although there is no perfect environmental analog to Mars on Earth, quantitative study of relevant terrestrial field sites can serve as the basis for physical models and technology development to aid future exploration. This dissertation describes original field and laboratory research on two terrestrial analog sites: Licancabur Volcano, Bolivia, and the Atacama Desert, Chile. Atop Licancabur, at an elevation of nearly 6,000 meters above sea level, sits the highest volcanic lake on Earth. Prior to this work, little was known about the lake, its waters, the role of volcanism or its potential relationship to locales on Mars. In the first part of this work, I describe observations of the lake resulting from several years of field study, including data on meteorological conditions and solar irradiance. These and other measurements provide the basis for (1) the first quantitative mass and energy balance model of the lake, and (2) the first determination of the altitude effect on solar visible and ultraviolet flux from the high altitude summit. Under the observed conditions, model results indicate: lake waters are primarily meteoric in origin and evaporating rapidly; volcanic input is not required to explain observations of lake water temperature or year-end model results. Nearby, Chile's Atacama Desert is known to be one of the driest, most inhospitable environments on Earth. There, environmental similarities to Mars provide an apt testing ground for new astrobiological exploration technologies. In the latter part of this work, I present results from my work with the Life In The Atacama (LITA) Mars rover field experiment. In particular, I report on the development of a new data analysis tool named the LITA Data Scoring System (DSS). Subject to the user-defined constraints, the DSS was used to facilitate targeting, analysis and mapping of rover science results relevant to potential habitability and evidence for life at three desert field sites. Although experimental in

  20. Avian influenza in Chile: a successful experience.

    Science.gov (United States)

    Max, Vanessa; Herrera, José; Moreira, Rubén; Rojas, Hernán

    2007-03-01

    Avian influenza (AI) was diagnosed in May 2002 for the first time in Chile and South America. The epidemic was caused by the highly pathogenic AI (HPAI) virus subtype H7N3 that emerged from a low pathogenic virus. The index farm was a broiler breeder, located in San Antonio, V Region, which at the time was a densely populated poultry area. Stamping of 465,000 breeders, in 27 sheds, was immediately conducted. Surveillance activities detected a second outbreak, 1 wk later, at a turkey breeding farm from the same company. The second farm was located 4 km from the index case. Only 25% of the sheds were infected, and 18,500 turkeys were destroyed. In both outbreaks, surveillance zones and across-country control measures were established: prediagnosis quarantine, depopulation, intensive surveillance, movement control, and increased biosecurity. Other measures included cleaning, disinfection, and controlling the farms with sentinels to detect the potential presence of the virus. Zoning procedures were implemented to allow the international trade of poultry products from unaffected areas. Positive serologic results to H5N2 virus also were detected in other poultry farms, but there was no evidence of clinical signs or virus isolation. Epidemiological investigation and laboratory confirmation determined that positive serology was related to a contaminated imported batch of vaccine against inclusion body hepatitis. All actions taken allowed the control of the epidemic, and within 7 mo, Chile was free of AI. Epidemic and control measures that prevented further spread are described in this article, which illustrates the importance of a combination of control measures during and after an outbreak of AI. This study is a good example of how veterinary services need to respond if their country is affected by HPAI.

  1. Volcano related atmospheric toxicants in Hilo and Hawaii Volcanoes National Park: implications for human health.

    Science.gov (United States)

    Michaud, Jon-Pierre; Krupitsky, Dmitry; Grove, John S; Anderson, Bruce S

    2005-08-01

    Volcanic fog (vog) from Kilauea volcano on the island of Hawaii includes a variety of chemical species including sulfur compounds and traces of metals such as mercury. The metal species seen tended to be in the nanograms per cubic meter range, whereas oxides of sulfur: SO2 and SO3 and sulfate aerosols, were in the range of micrograms per cubic meter and rarely even as high as a few milligrams per cubic meter of air (nominally ppb to ppm). These sulfur species are being investigated for associations with both acute and chronic changes in human health status. The sulfate aerosols tend to be less than 1 microm in diameter and tend to dominate the mass of this submicron size mode. The sulfur chemistry is dynamic, changing composition from predominantly sulfur dioxide and trioxide gasses near the volcano, to predominantly sulfate aerosols on the west side of the island. Time, concentration and composition characteristics of submicron aerosols and sulfur dioxide are described with respect to the related on-going health studies and public health management concerns. Exposures to sulfur dioxide and particulate matter equal to or less than 1 microm in size were almost always below the national ambient air quality standards (NAAQS). These standards do not however consider the acidic nature and submicron size of the aerosol, nor the possibility of the aerosol and the sulfur dioxide interacting in their toxicity. Time series plots, histograms and descriptive statistics of hourly averages give the reader a sense of some of the exposures observed.

  2. Continuous Dropout.

    Science.gov (United States)

    Shen, Xu; Tian, Xinmei; Liu, Tongliang; Xu, Fang; Tao, Dacheng

    2017-10-03

    Dropout has been proven to be an effective algorithm for training robust deep networks because of its ability to prevent overfitting by avoiding the co-adaptation of feature detectors. Current explanations of dropout include bagging, naive Bayes, regularization, and sex in evolution. According to the activation patterns of neurons in the human brain, when faced with different situations, the firing rates of neurons are random and continuous, not binary as current dropout does. Inspired by this phenomenon, we extend the traditional binary dropout to continuous dropout. On the one hand, continuous dropout is considerably closer to the activation characteristics of neurons in the human brain than traditional binary dropout. On the other hand, we demonstrate that continuous dropout has the property of avoiding the co-adaptation of feature detectors, which suggests that we can extract more independent feature detectors for model averaging in the test stage. We introduce the proposed continuous dropout to a feedforward neural network and comprehensively compare it with binary dropout, adaptive dropout, and DropConnect on Modified National Institute of Standards and Technology, Canadian Institute for Advanced Research-10, Street View House Numbers, NORB, and ImageNet large scale visual recognition competition-12. Thorough experiments demonstrate that our method performs better in preventing the co-adaptation of feature detectors and improves test performance.

  3. EPIDEMIOLOGÍA DE LA DIABETES MELLITUS EN CHILE

    Directory of Open Access Journals (Sweden)

    Jorge Sapunar Z., MD, MSC, FACP

    2016-03-01

    Finalmente, la frecuencia, morbilidad y mortalidad de la diabetes mellitus, se suman para explicar que el manejo de la enfermedad y sus complicaciones consuma el 10,2% del presupuesto en salud de Chile.

  4. All projects related to Chile | Page 4 | IDRC - International ...

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

    ... complex knowledge economy demands economic, social and environmental data ... Region: Brazil, South America, Chile, Colombia, Uruguay, North and Central ... Labour Market Regulations, Outcomes and Income Distribution in Colombia ...

  5. Science, Technology, and Innovation in Chile | IDRC - International ...

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

    Book cover Science, Technology, and Innovation in Chile ... With this in mind, and following a conversation between Canadian Prime Minister Jean Chrétien and ... Call for new OWSD Fellowships for Early Career Women Scientists now open.

  6. Discovering Chile's hidden water treasures – rock glaciers | IDRC ...

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

    2011-05-30

    May 30, 2011 ... This means the research methods for investigating rock glaciers are ... group advising Chile's national environmental protection agency on ... Communities' perception of climate change risks in South America's Atlantic coasts.

  7. CASE STUDY: Chile — Health, environment, and indigenous culture ...

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

    2011-01-06

    Jan 6, 2011 ... CASE STUDY: Chile — Health, environment, and indigenous culture .... For example, the National Corporation for Indigenous Development (CONADI) ... Institute for Agriculture Development (INDAP), and applied research on ...

  8. Evictions and the Right to Housing: Experience from Canada, Chile ...

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

    ... Experience from Canada, Chile, the Dominican Republic, South Africa, and South Korea ... all of whom are working to defend and advance the right to housing. ... IDRC congratulates first cohort of Women in Climate Change Science Fellows.

  9. All projects related to Chile | Page 3 | IDRC - International ...

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

    The Maipo River Basin in central Chile is home to six million people, most residing in the city of ... Program: Climate Change ... Program: Governance and Justice ... Rethinking Political Legitimacy: Citizen Inclusion and Social Digital Media.

  10. Tephra compositions from Late Quaternary volcanoes around the Antarctic Peninsula

    Science.gov (United States)

    Kraus, S.

    2009-12-01

    Crustal extension and rifting processes opened the Bransfield Strait between the South Shetland Islands and the Antarctic Peninsula during the last 4 Ma. Similar processes on the Peninsula's eastern side are responsible for volcanism along Larsen Rift. There are at least 11 volcanic centers with known or suspected Late Pleistocene / Holocene explosive activity (Fig. 1). Fieldwork was carried out on the islands Deception, Penguin, Bridgeman and Paulet, moreover at Melville Peak (King George Is.) and Rezen Peak (Livingston Is.). Of special importance is the second ever reported visit and sampling at Sail Rock, and the work on never before visited outcrops on the northern slopes and at the summit of Cape Purvis volcano (Fig. 1). The new bulk tephra ICP-MS geochemical data provide a reliable framework to distinguish the individual volcanic centers from each other. According to their Mg-number, Melville Peak and Penguin Island represent the most primitive magma source. Nb/Y ratios higher than 0.67 in combination with elevated Th/Yb and Ta/Yb ratios and strongly enriched LREE seem to be diagnostic to distinguish the volcanoes located along the Larsen Rift from those associated with Bransfield Rift. Sr/Y ratios discriminate between the individual Larsen Rift volcanoes, Paulet Island showing considerably higher values than Cape Purvis volcano. Along Bransfield Rift, Bridgeman Island and Melville Peak have notably lower Nb/Y and much higher Th/Nb than Deception Island, Penguin Island and Sail Rock. The latter displays almost double the Th/Yb ratio as compared to Deception Island, and also much higher LREE enrichment but extraordinarily low Ba/Th, discriminating it from Penguin Island. Such extremely low Ba/Th ratios are also typical for Melville Peak, but for none of the other volcanoes. Penguin Island has almost double the Ba/Th and Sr/Y ratios higher than any other investigated volcano. Whereas the volcanoes located in the northern part of Bransfield Strait have Zr

  11. Diffuse He degassing from Cumbre Vieja volcano, La Palma, Canary Islands

    Science.gov (United States)

    Asensio-Ramos, María; De Jongh, Marli E.; Lamfers, Kristen R.; Alonso, Mar; Amonte, Cecilia; Padrón, Eleazar; Hernández, Pedro A.; Pérez, Nemesio M.

    2017-04-01

    Helium is considered as an ideal geochemical tracer due to its geochemical properties: chemical inertness, physical stability and practical insolubility in water under normal conditions. These characteristics, together with its high mobility on the crust, make the presence of helium anomalies on the surface environment of a volcanic system to be related to deep fluid migration controlled by volcano-tectonic features, also providing valuable information about the location and characteristics of the gas source and the fracturing of the crust. The recent results reported by Padrón et al. (2013) clearly show importance of helium emission studies for the prediction of major volcanic events and the importance of continuous monitoring of this gas in active volcanic regions. La Palma Island (708.32 km2) is located at the northwestern end of the Canarian Archipelago. Subaerial volcanic activity on this island started ˜2.0 My ago and has taken place exclusively at the southern part in the last 123 ka. Cumbre Vieja volcano, the most active basaltic volcano of the Canary Islands, was built in this zone, including a main north-south rift area 20 km long and up to 1,950 m in elevation, with vents located also at the northwest and northeast. Padrón et al., (2012) showed that helium is mainly emitted along both N-S and N-W rift of Cumbre Vieja, being, therefore, zones of enhanced permeability for deep gas migration and preferential routes for degassing. This work represents a continuation of the results obtained by Padrón et al. (2012) until the year 2016. Each study covered the 220 km2 of Cumbre Vieja with an average of 570 homogenously distributed sampling points. At each sampling site, soil gas samples were collected at 40 cm depth by withdrawing the gas aliquots into 60 cc hypodermic syringes. He content in the soil gases was analyzed by means of quadrupole mass spectrometry (QMS). Atmospheric gas was used periodically to calibrate the instrument. To estimate the helium

  12. Tephra-Producing Eruptions of Holocene Age at Akutan Volcano, Alaska; Frequency, Magnitude, and Hazards

    Science.gov (United States)

    Waythomas, C. F.; Wallace, K. L.; Schwaiger, H.

    2012-12-01

    Akutan Volcano in the eastern Aleutian Islands of Alaska is one of the most historically active volcanoes in the Aleutian arc (43 eruptions in about the past 250 years). Explosive eruptions pose major hazards to aircraft flying north Pacific air routes and to local infrastructure on Akutan and neighboring Unalaska Island. Air travel, infrastructure, and population in the region have steadily increased during the past several decades, and thus it is important to better understand the frequency, magnitude, and characteristics of tephra-producing eruptions. The most recent eruption was a VEI 2 event on March 8-May 21, 1992 that resulted in minor ash emissions and trace amounts of proximal fallout. Nearly continuous low-level emission of ash and steam is typical of historical eruptions, and most of the historical events have been similar in magnitude to the 1992 event. The most recent major eruption occurred about 1600 yr. B.P. and likely produced the ca. 2-km diameter summit caldera and inundated valleys that head on the volcano with pyroclastic-flow and lahar deposits that are tens of meters thick. The 1600 yr. B.P. eruption covered most of Akutan Island with up to 2.5 m of coarse scoriaceous tephra fall, including deposits 0.5-1 m thick near the City of Akutan. Tephra-fall deposits associated with this eruption exhibit a continuous sequence of black, fine to coarse scoriaceous lapilli overlain by a lithic-rich facies and finally a muddy aggregate-rich facies indicating water involvement during the latter stages of the eruption. Other tephra deposits of Holocene age on Akutan Island include more than a dozen discrete fine to coarse ash beds and 3-6 beds of scoriaceous, coarse lapilli tephra indicating that there have been several additional major eruptions (>VEI 3) of Akutan Volcano during the Holocene. Radiocarbon dates on these events are pending. In addition to tephra falls from Akutan, other fine ash deposits are found on the island that originated from other

  13. Continuity theory

    CERN Document Server

    Nel, Louis

    2016-01-01

    This book presents a detailed, self-contained theory of continuous mappings. It is mainly addressed to students who have already studied these mappings in the setting of metric spaces, as well as multidimensional differential calculus. The needed background facts about sets, metric spaces and linear algebra are developed in detail, so as to provide a seamless transition between students' previous studies and new material. In view of its many novel features, this book will be of interest also to mature readers who have studied continuous mappings from the subject's classical texts and wish to become acquainted with a new approach. The theory of continuous mappings serves as infrastructure for more specialized mathematical theories like differential equations, integral equations, operator theory, dynamical systems, global analysis, topological groups, topological rings and many more. In light of the centrality of the topic, a book of this kind fits a variety of applications, especially those that contribute to ...

  14. Deep long-period earthquakes beneath Washington and Oregon volcanoes

    Science.gov (United States)

    Nichols, M.L.; Malone, S.D.; Moran, S.C.; Thelen, W.A.; Vidale, J.E.

    2011-01-01

    Deep long-period (DLP) earthquakes are an enigmatic type of seismicity occurring near or beneath volcanoes. They are commonly associated with the presence of magma, and found in some cases to correlate with eruptive activity. To more thoroughly understand and characterize DLP occurrence near volcanoes in Washington and Oregon, we systematically searched the Pacific Northwest Seismic Network (PNSN) triggered earthquake catalog for DLPs occurring between 1980 (when PNSN began collecting digital data) and October 2009. Through our analysis we identified 60 DLPs beneath six Cascade volcanic centers. No DLPs were associated with volcanic activity, including the 1980-1986 and 2004-2008 eruptions at Mount St. Helens. More than half of the events occurred near Mount Baker, where the background flux of magmatic gases is greatest among Washington and Oregon volcanoes. The six volcanoes with DLPs (counts in parentheses) are Mount Baker (31), Glacier Peak (9), Mount Rainier (9), Mount St. Helens (9), Three Sisters (1), and Crater Lake (1). No DLPs were identified beneath Mount Adams, Mount Hood, Mount Jefferson, or Newberry Volcano, although (except at Hood) that may be due in part to poorer network coverage. In cases where the DLPs do not occur directly beneath the volcanic edifice, the locations coincide with large structural faults that extend into the deep crust. Our observations suggest the occurrence of DLPs in these areas could represent fluid and/or magma transport along pre-existing tectonic structures in the middle crust. ?? 2010 Elsevier B.V.

  15. Using geodetic data to infer the kinematic and mechanical properties of deformation sources on Kilauea Volcano, Hawaii

    Science.gov (United States)

    Cervelli, Peter Francis

    2002-09-01

    Paradoxically, one of the greatest hazards associated with oceanic volcanoes is not volcanic. Rather, it is the potential for catastrophic flank failure resulting in devastating tsunamis, which threaten not just the immediate vicinity, but coastal cities along the entire rim of an ocean basin. Kilauea volcano on the Island of Hawaii, USA, a potential source of such flank failures, is monitored by a network of continuously recording geodetic instruments, including Global Positioning System (GPS) receivers, tiltmeters, and strainmeters. In this thesis, methodology is developed for using these geodetic data to estimate the geometry and type of active deformation sources, such as dikes, magma chambers, and faults. The methodology is then applied to two episodes of deformation that occurred at Kilauea Volcano in 1999 and 2000. First, the deformation associated with an earthquake swarm on September 12, 1999 in the Upper East Rift Zone of Kilauea Volcano, which was recorded by continuous GPS receivers, tiltmeters, campaign GPS, leveling, and InSAR, is analyzed and interpreted as a west to east propagating dike intrusion. Lack of premonitory inflation of Kilauea's summit suggests that the immediate cause of the intrusion was probably tensile failure in the shallow crust of the Upper East Rift, rather than forceful magma injection. Second, in early November 2000, the geodetic network recorded transient southeastward displacements, which we interpret as an episode of aseismic fault slip. The duration of the event was about 36 hours; it had an equivalent moment magnitude of M5.7, and a maximum slip velocity of about 6 cm/day. Inversion of the GPS data images a shallowly dipping thrust at a depth of 4.5 km that we interpret as the down dip extension of the Hilina Pali fault system. Thus it is demonstrated that continuous geodetic networks can detect accelerating slip, potentially leading to warnings of imminent volcanic flank collapse. Finally, in the last chapter of the

  16. Decades lost and found: Mexico and Chile since 1980

    OpenAIRE

    Raphael Bergoeing; Patrick J. Kehoe; Timothy J. Kehoe; Raimundo Soto

    2002-01-01

    Both Chile and Mexico experienced severe economic crises in the early 1980s, yet Chile recovered much faster than Mexico. This study analyzes four possible explanations for this difference and rules out three, explanations based on money supply expansion, real wage and real exchange rate declines, and foreign debt overhangs. The fourth explanation is based on government policy reforms in the two countries. Using growth accounting and a calibrated growth model, the study determines that the on...

  17. Bullfighting at Santiago de Chile during the Colonial Period

    Directory of Open Access Journals (Sweden)

    Escardiel González Estévez

    2017-06-01

    Full Text Available Despite the fact that in Chile there is no bullfighting and that people have forgotten it, bulls existed in this territory as in any other Spanish colony, with critical social implications. Although follow the Iberian trend, from ritual to a spectacle, some local factors made that bullfighting had special features in Chile, as is the case of the permanence of chivalrous bullfighting in the context of military training at the frontier with mapuche people.

  18. Illegitimate patients: Undocumented immigrants’ access to health care in Chile

    OpenAIRE

    Nanette Paz Liberona Concha; Miguel Angel Mansilla

    2017-01-01

    In recent decades, Chile has become a destination for immigrants from other South American countries, which has significantly impacted public services – particularly the public health system – at the economic, social, and cultural levels. The aim of this paper is to provide substantiated information on issues concerning undocumented immigrants’ access to health care in Chile. A qualitative methodology, fundamentally an ethnography of the clinical setting, was used. Results were then analyzed ...

  19. International Collaboration on Building Local Technical Capacities for Monitoring Volcanic Activity at Pacaya Volcano, Guatemala.

    Science.gov (United States)

    Escobar-Wolf, R. P.; Chigna, G.; Morales, H.; Waite, G. P.; Oommen, T.; Lechner, H. N.

    2015-12-01

    Pacaya volcano is a frequently active and potentially dangerous volcano situated in the Guatemalan volcanic arc. It is also a National Park and a major touristic attraction, constituting an important economic resource for local municipality and the nearby communities. Recent eruptions have caused fatalities and extensive damage to nearby communities, highlighting the need for risk management and loss reduction from the volcanic activity. Volcanic monitoring at Pacaya is done by the Instituto Nacional de Sismologia, Vulcanologia, Meteorologia e Hidrologia (INSIVUMEH), instrumentally through one short period seismic station, and visually by the Parque Nacional Volcan de Pacaya y Laguna de Calderas (PNVPLC) personnel. We carry out a project to increase the local technical capacities for monitoring volcanic activity at Pacaya. Funding for the project comes from the Society of Exploration Geophysicists through the Geoscientists Without Borders program. Three seismic and continuous GPS stations will be installed at locations within 5 km from the main vent at Pacaya, and one webcam will aid in the visual monitoring tasks. Local educational and outreach components of the project include technical workshops on data monitoring use, and short thesis projects with the San Carlos University in Guatemala. A small permanent exhibit at the PNVPLC museum or visitor center, focusing on the volcano's history, hazards and resources, will also be established as part of the project. The strategy to involve a diverse group of local collaborators in Guatemala aims to increase the chances for long term sustainability of the project, and relies not only on transferring technology but also the "know-how" to make that technology useful. Although not a primary research project, it builds on a relationship of years of joint research projects at Pacaya between the participants, and could be a model of how to increase the broader impacts of such long term collaboration partnerships.

  20. Volcano geodesy: The search for magma reservoirs and the formation of eruptive vents

    Science.gov (United States)

    Dvorak, J.J.; Dzurisin, D.

    1997-01-01

    Routine geodetic measurements are made at only a few dozen of the world's 600 or so active volcanoes, even though these measurements have proven to be a reliable precursor of eruptions. The pattern and rate of surface displacement reveal the depth and rate of pressure increase within shallow magma reservoirs. This process has been demonstrated clearly at Kilauea and Mauna Loa, Hawaii; Long Valley caldera, California; Campi Flegrei caldera, Italy; Rabaul caldera, Papua New Guinea; and Aira caldera and nearby Sakurajima, Japan. Slower and lesser amounts of surface displacement at Yellowstone caldera, Wyoming, are attributed to changes in a hydrothermal system that overlies a crustal magma body. The vertical and horizontal dimensions of eruptive fissures, as well as the amount of widening, have been determined at Kilauea, Hawaii; Etna, Italy; Tolbachik, Kamchatka; Krafla, Iceland; and Asal-Ghoubbet, Djibouti, the last a segment of the East Africa Rift Zone. Continuously recording instruments, such as tiltmeters, extensometers, and dilatometers, have recorded horizontal and upward growth of eruptive fissures, which grew at rates of hundreds of meters per hour, at Kilauea; Izu-Oshima, Japan; Teishi Knoll seamount, Japan; and Piton de la Fournaise, Re??union Island. In addition, such instruments have recorded the hour or less of slight ground movement that preceded small explosive eruptions at Sakurajima and presumed sudden gas emissions at Galeras, Colombia. The use of satellite geodesy, in particular the Global Positioning System, offers the possibility of revealing changes in surface strain both local to a volcano and over a broad region that includes the volcano.

  1. Real-time source deformation modeling through GNSS permanent stations at Merapi volcano (Indonesia

    Science.gov (United States)

    Beauducel, F.; Nurnaning, A.; Iguchi, M.; Fahmi, A. A.; Nandaka, M. A.; Sumarti, S.; Subandriyo, S.; Metaxian, J. P.

    2014-12-01

    Mt. Merapi (Java, Indonesia) is one of the most active and dangerous volcano in the world. A first GPS repetition network was setup and periodically measured since 1993, allowing detecting a deep magma reservoir, quantifying magma flux in conduit and identifying shallow discontinuities around the former crater (Beauducel and Cornet, 1999;Beauducel et al., 2000, 2006). After the 2010 centennial eruption, when this network was almost completely destroyed, Indonesian and Japanese teams installed a new continuous GPS network for monitoring purpose (Iguchi et al., 2011), consisting of 3 stations located at the volcano flanks, plus a reference station at the Yogyakarta Observatory (BPPTKG).In the framework of DOMERAPI project (2013-2016) we have completed this network with 5 additional stations, which are located on the summit area and volcano surrounding. The new stations are 1-Hz sampling, GNSS (GPS + GLONASS) receivers, and near real-time data streaming to the Observatory. An automatic processing has been developed and included in the WEBOBS system (Beauducel et al., 2010) based on GIPSY software computing precise daily moving solutions every hour, and for different time scales (2 months, 1 and 5 years), time series and velocity vectors. A real-time source modeling estimation has also been implemented. It uses the depth-varying point source solution (Mogi, 1958; Williams and Wadge, 1998) in a systematic inverse problem model exploration that displays location, volume variation and 3-D probability map.The operational system should be able to better detect and estimate the location and volume variations of possible magma sources, and to follow magma transfer towards the surface. This should help monitoring and contribute to decision making during future unrest or eruption.

  2. Rangitoto Volcano Drilling Project: Life of a Small 'Monogenetic' Basaltic Shield in the Auckland Volcanic Field

    Science.gov (United States)

    Shane, P. A. R.; Linnell, T.; Lindsay, J. M.; Smith, I. E.; Augustinus, P. M.; Cronin, S. J.

    2014-12-01

    Rangitoto is a small basaltic shield volcano representing the most recent and most voluminous episode of volcanism in the Auckland Volcanic Field, New Zealand. Auckland City is built on the field, and hence, Rangitoto's importance in hazard-risk modelling. The symmetrical edifice, ~6 km wide and 260 m high, has volume of 1.78 km3. It comprises summit scoria cones and a lava field. However, the lack of deep erosion dissection has prevented the development of an eruptive stratigraphy. Previous studies suggested construction in a relatively short interval at 550-500 yrs BP. However, microscopic tephra have been interpreted as evidence of intermittent activity from 1498 +/- 140 to 504 +/- 6 yrs BP, a longevity of 1000 years. A 150-m-deep hole was drilled through the edifice in February 2014 to obtain a continuous core record. The result is an unparalleled stratigraphy of the evolution of a small shield volcano. The upper 128 m of core comprises at least 27 lava flows with thicknesses in the range 0.3-15 m, representing the main shield-building phase. Underlying marine sediments are interbedded with 8 m of pyroclastic lapilli, and a thin lava flow, representing the explosive phreatomagmatic birth of the volcano. Preliminary geochemical analyses reveal suite of relatively uniform transitional basalts (MgO = 8.1 to 9.7 wt %). However, 4 compositional groups are distinguished that were erupted in sequential order. High-MgO magmas were erupted first, followed by a two more heterogeneous groups displaying differentiation trends with time. Finally, distinct low-MgO basalts were erupted. Each magma type appears to represent a new magma batch. The core places the magma types in a time series, which can be correlated to the surface lava field. Hence, allowing a geometrical reconstruction of the shield growth. Additional petrologic investigations are providing insight to magmatic ascent processes, while radiocarbon and paleomagnetic secular variation studies will reveal the

  3. Behavioral problems and tobacco use among adolescents in Chile

    Directory of Open Access Journals (Sweden)

    Caris Luis

    2003-01-01

    Full Text Available OBJECTIVE: To examine the association between behavioral problems and tobacco smoking among adolescent students in Chile. METHODS: Data were drawn from a study that included questionnaire surveys of 46 907 school-attending adolescents in all 13 of the administrative regions of Chile. Assessments were based on an adapted, Spanish-language version of the Drug Use Screening Inventory. The conditional form of the logistic regression model was used for analysis, with matching of students on individual schools, and with further statistical adjustments for sex, age, and selected risk factors. RESULTS: The prevalence of tobacco smoking among the adolescents was very high across all of Chile, with a level between 56% and 65% in each of the 13 regions. The estimated odds of tobacco use in youths at the highest level of behavioral problems was about twice that for youths at the lowest levels, both before and after controlling for sex, age, lack of participation in recreational activities, level of irritability, and levels of problems with school, family attention, and mental health. CONCLUSIONS: These findings help to complement and complete the evidence of prior studies on tobacco smoking among adolescents with behavior problems, including recent research on Central American youths. Although the magnitude of observed associations in Chile was not as great as that for the associations found in Central America, both the strength of these associations and their statistical significance were observed throughout Chile. This is the first study in Chile on potentially causal relationships such as these.

  4. Continuation calculus

    NARCIS (Netherlands)

    Geron, B.; Geuvers, J.H.; de'Liguoro, U.; Saurin, A.

    2013-01-01

    Programs with control are usually modeled using lambda calculus extended with control operators. Instead of modifying lambda calculus, we consider a different model of computation. We introduce continuation calculus, or CC, a deterministic model of computation that is evaluated using only head

  5. Basaltic cannibalism at Thrihnukagigur volcano, Iceland

    Science.gov (United States)

    Hudak, M. R.; Feineman, M. D.; La Femina, P. C.; Geirsson, H.

    2014-12-01

    Magmatic assimilation of felsic continental crust is a well-documented, relatively common phenomenon. The extent to which basaltic crust is assimilated by magmas, on the other hand, is not well known. Basaltic cannibalism, or the wholesale incorporation of basaltic crustal material into a basaltic magma, is thought to be uncommon because basalt requires more energy than higher silica rocks to melt. Basaltic materials that are unconsolidated, poorly crystalline, or palagonitized may be more easily ingested than fully crystallized massive basalt, thus allowing basaltic cannibalism to occur. Thrihnukagigur volcano, SW Iceland, offers a unique exposure of a buried cinder cone within its evacuated conduit, 100 m below the main vent. The unconsolidated tephra is cross-cut by a NNE-trending dike, which runs across the ceiling of this cave to a vent that produced lava and tephra during the ~4 Ka fissure eruption. Preliminary petrographic and laser ablation inductively coupled mass spectrometry (LA-ICP-MS) analyses indicate that there are two populations of plagioclase present in the system - Population One is stubby (aspect ratio 2.1), subhedral to euhedral, and has much higher Ba/Sr ratios. Population One crystals are observed in the cinder cone, dike, and surface lavas, whereas Population Two crystals are observed only in the dike and surface lavas. This suggests that a magma crystallizing a single elongate population of plagioclase intruded the cinder cone and rapidly assimilated the tephra, incorporating the stubbier population of phenocrysts. This conceptual model for basaltic cannibalism is supported by field observations of large-scale erosion upward into the tephra, which is coated by magma flow-back indicating that magma was involved in the thermal etching. While the unique exposure at Thrihnukagigur makes it an exceptional place to investigate basaltic cannibalism, we suggest that it is not limited to this volcanic system. Rather it is a process that likely

  6. Study a Relation Between the Lascar Volcano Microseimicity and Changes in the Local System of Lineaments, Obtained Using the Landsat 8 Images.

    Science.gov (United States)

    Arellano-Baeza, A. A.; Soto-Pinto, C. A.

    2014-12-01

    Over the last decades strong efforts have been made to apply new spaceborn technologies to the study of volcanic activity. Recent studies have shown that the high resolution satellite images can be very useful for tracking of evolution of the stress patterns related to the volcanic activity. It can be done by observing the changes in density and orientation of lineaments extracted from satellite images. A lineament is generally defined as a straight or a somewhat curved feature in the landscape visible in a satellite image as an aligned sequence of pixels of a contrasting intensity compared to the background. The system of lineaments extracted from the satellite images is not identical to the geological lineaments which are usually determined by land-based surveys, nevertheless, it generally reflects the structure of the faults and fractures in the Earth's crust. For this study the lineaments were detected using the ADALGEO software, based on the Hough transform (Soto-Pinto et al, 2013). A temporal sequence of the Landsat 8 multispectral images of the Lascar volcano, located in the North of Chile, was used to study changes in lineament configuration during 2013-2014. It was found that, the number and orientation of lineaments is affected by microseimicity. In particular, it was found that often the density of lineaments decreases with the intensity of microseisms, which could be related to the volcano inflation.

  7. A novel approach to estimate the eruptive potential and probability in open conduit volcanoes.

    Science.gov (United States)

    De Gregorio, Sofia; Camarda, Marco

    2016-07-26

    In open conduit volcanoes, volatile-rich magma continuously enters into the feeding system nevertheless the eruptive activity occurs intermittently. From a practical perspective, the continuous steady input of magma in the feeding system is not able to produce eruptive events alone, but rather surplus of magma inputs are required to trigger the eruptive activity. The greater the amount of surplus of magma within the feeding system, the higher is the eruptive probability.Despite this observation, eruptive potential evaluations are commonly based on the regular magma supply, and in eruptive probability evaluations, generally any magma input has the same weight. Conversely, herein we present a novel approach based on the quantification of surplus of magma progressively intruded in the feeding system. To quantify the surplus of magma, we suggest to process temporal series of measurable parameters linked to the magma supply. We successfully performed a practical application on Mt Etna using the soil CO2 flux recorded over ten years.

  8. Factores que inciden en el financiamiento de los estudios Universitarios en Chile Factors that impact on funding for higher education in Chile

    Directory of Open Access Journals (Sweden)

    Rodolfo Schmal

    2007-06-01

    Full Text Available El artículo da cuenta de los principales factores que inciden en el financiamiento de los estudios universitarios en Chile, exponiéndose los fundamentos y relaciones de un modelo para estimar el volumen de los recursos comprometidos y sus opciones de provisión. En las últimas dos década el mercado universitario ha duplicando su masa de estudiantes fenómeno que continuará por esta senda, implicando serias presiones sobre el financiamiento público, en un sistema que ya tiene una elevada participación financiera privada. El modelo que se propone apunta a proveer un enfoque sistémico para abordar la problemática planteada.The article covers the main factors that impact on funding higher education in Chile, presenting the fundaments and relations of a model to estimate the volume of resources committed and options for provision. In the last two decades the university market has doubled its total of students - a phenomenon that should continue, entailing serious pressures on public funding. The model proposed here points to a systems approach to the problem.

  9. Postshield stage transitional volcanism on Mahukona Volcano, Hawaii

    Science.gov (United States)

    Clague, D.A.; Calvert, A.T.

    2009-01-01

    Age spectra from 40Ar/39Ar incremental heating experiments yield ages of 298??25 ka and 310??31 ka for transitional composition lavas from two cones on submarine Mahukona Volcano, Hawaii. These ages are younger than the inferred end of the tholeiitic shield stage and indicate that the volcano had entered the postshield alkalic stage before going extinct. Previously reported elevated helium isotopic ratios of lavas from one of these cones were incorrectly interpreted to indicate eruption during a preshield alkalic stage. Consequently, high helium isotopic ratios are a poor indicator of eruptive stage, as they occur in preshield, shield, and postshield stage lavas. Loihi Seamount and Kilauea are the only known Hawaiian volcanoes where the volume of preshield alkalic stage lavas can be estimated. ?? Springer-Verlag 2008.

  10. Sutter Buttes-the lone volcano in California's Great Valley

    Science.gov (United States)

    Hausback, Brain P.; Muffler, L.J. Patrick; Clynne, Michael A.

    2011-01-01

    The volcanic spires of the Sutter Buttes tower 2,000 feet above the farms and fields of California's Great Valley, just 50 miles north-northwest of Sacramento and 11 miles northwest of Yuba City. The only volcano within the valley, the Buttes consist of a central core of volcanic domes surrounded by a large apron of fragmental volcanic debris. Eruptions at the Sutter Buttes occurred in early Pleistocene time, 1.6 to 1.4 million years ago. The Sutter Buttes are not part of the Cascade Range of volcanoes to the north, but instead are related to the volcanoes in the Coast Ranges to the west in the vicinity of Clear Lake, Napa Valley, and Sonoma Valley.

  11. Digital Geologic Map Database of Medicine Lake Volcano, Northern California

    Science.gov (United States)

    Ramsey, D. W.; Donnelly-Nolan, J. M.; Felger, T. J.

    2010-12-01

    Medicine Lake volcano, located in the southern Cascades ~55 km east-northeast of Mount Shasta, is a large rear-arc, shield-shaped volcano with an eruptive history spanning nearly 500 k.y. Geologic mapping of Medicine Lake volcano has been digitally compiled as a spatial database in ArcGIS. Within the database, coverage feature classes have been created representing geologic lines (contacts, faults, lava tubes, etc.), geologic unit polygons, and volcanic vent location points. The database can be queried to determine the spatial distributions of different rock types, geologic units, and other geologic and geomorphic features. These data, in turn, can be used to better understand the evolution, growth, and potential hazards of this large, rear-arc Cascades volcano. Queries of the database reveal that the total area covered by lavas of Medicine Lake volcano, which range in composition from basalt through rhyolite, is about 2,200 km2, encompassing all or parts of 27 U.S. Geological Survey 1:24,000-scale topographic quadrangles. The maximum extent of these lavas is about 80 km north-south by 45 km east-west. Occupying the center of Medicine Lake volcano is a 7 km by 12 km summit caldera in which nestles its namesake, Medicine Lake. The flanks of the volcano, which are dotted with cinder cones, slope gently upward to the caldera rim, which reaches an elevation of nearly 2,440 m. Approximately 250 geologic units have been mapped, only half a dozen of which are thin surficial units such as alluvium. These volcanic units mostly represent eruptive events, each commonly including a vent (dome, cinder cone, spatter cone, etc.) and its associated lava flow. Some cinder cones have not been matched to lava flows, as the corresponding flows are probably buried, and some flows cannot be correlated with vents. The largest individual units on the map are all basaltic in composition, including the late Pleistocene basalt of Yellowjacket Butte (296 km2 exposed), the largest unit on the

  12. Earth Girl Volcano: An Interactive Game for Disaster Preparedness

    Science.gov (United States)

    Kerlow, Isaac

    2017-04-01

    Earth Girl Volcano is an interactive casual strategy game for disaster preparedness. The project is designed for mainstream audiences, particularly for children, as an engaging and fun way to learn about volcano hazards. Earth Girl is a friendly character that kids can easily connect with and she helps players understand how to best minimize volcanic risk. Our previous award-winning game, Earth Girl Tsunami, has seen success on social media, and is available as a free app for both Android and iOS tables and large phones in seven languages: Indonesian, Thai, Tamil, Japanese, Chinese, Spanish, French and English. This is the first public viewing of the Earth Girl Volcano new game prototype.

  13. Multiple Active Volcanoes in the Northeast Lau Basin

    Science.gov (United States)

    Baker, E. T.; Resing, J. A.; Lupton, J. E.; Walker, S. L.; Embley, R. W.; Rubin, K. H.; Buck, N.; de Ronde, C. E.; Arculus, R. J.

    2010-12-01

    The northeast Lau Basin occupies a complex geological area between the Tafua arc front, the E-W trending Tonga Trench, and the Northeast Lau Spreading Center. These boundaries create multiple zones of extension and thus provide abundant opportunities for magma to invade the crust. The 25-km-long chain of “Mata” volcanoes lies near the center of this area, separated from both the arc front and the spreading ridge. In 2008 we discovered hydrothermal venting on the largest and most southerly of these volcanoes, W and E Mata. In 2010 we visited the 7 smaller volcanoes that form a 15-km-long arcuate sweep to the north from W and E Mata (the “North Matas”). We also revisited W and E Mata. Over each volcano we conducted CTD tows to map plumes and collect water samples. Based on the CTD results, camera tows searched for seafloor sources on three volcanoes. The N Mata volcanoes, extending from Mata Taha (1) in the south to Mata Fitu (7) in the north, lie within a prominent gap in the shallow bathymetry along the southern border of the Tonga trench. Northward from E Mata the Mata volcanoes degrade from large symmetrical cones to smaller and blocky volcanic edifices. Summit depths range from 1165 m (W Mata) to 2670 m (Mata Nima (5)). The most active volcano in the chain is the erupting W Mata, with an intense plume that extended 250 m above the summit. Hydrothermal temperature anomalies (Δθ, corrected for hydrographic masking effects) reached ˜1.7°C, with light-scattering values as high as 2-5 ΔNTU. The 2010 surveys now show that 6 of the 7 N Mata volcanoes are also hydrothermally active. Along the N Matas, Δθ and ΔNTU signals ranged from robust to weak, but distinct oxidation-reduction potential (aka Eh) anomalies confirmed active venting in each case. The most concentrated plumes were found near Mata Ua (2) and Mata Fitu (7), with Δθ and ΔNTU maxima of 0.1-0.17°C and 0.3, respectively. Despite the variability in plume strength, however, ΔNTU/Δθ ratios

  14. Determining the stress field in active volcanoes using focal mechanisms

    Directory of Open Access Journals (Sweden)

    Bruno Massa

    2016-11-01

    Full Text Available Stress inversion of seismological datasets became an essential tool to retrieve the stress field of active tectonics and volcanic areas. In particular, in volcanic areas, it is able to put constrains on volcano-tectonics and in general in a better understanding of the volcano dynamics. During the last decades, a wide range of stress inversion techniques has been proposed, some of them specifically conceived to manage seismological datasets. A modern technique of stress inversion, the BRTM, has been applied to seismological datasets available at three different regions of active volcanism: Mt. Somma-Vesuvius (197 Fault Plane Solutions, FPSs, Campi Flegrei (217 FPSs and Long Valley Caldera (38,000 FPSs. The key role of stress inversion techniques in the analysis of the volcano dynamics has been critically discussed. A particular emphasis was devoted to performances of the BRTM applied to volcanic areas.

  15. Inside the volcano: The how and why of Thrihnukagigur volcano, Iceland

    Science.gov (United States)

    LaFemina, Peter; Hudak, Michael; Feineman, Maureen; Geirsson, Halldor; Normandeau, Jim; Furman, Tanya

    2015-04-01

    The Thrihnukagigur volcano, located in the Brennisteinsfjöll fissure swarm on the Reykjanes Peninsula, Iceland, offers a unique exposure of the upper magmatic plumbing system of a monogenetic volcano. The volcano formed during a dike-fed strombolian eruption ~3500 BP with flow-back leaving an evacuated conduit, elongated parallel to the regional maximum horizontal stress. At least two vents were formed above the dike, as well as several small hornitos south-southwest of the main vent. In addition to the evacuated conduit, a cave exists 120 m below the vent. The cave exposes stacked lava flows and a buried cinder cone. The unconsolidated tephra of the cone is cross-cut by a NNE-trending dike, which runs across the ceiling of this cave to the vent that produced lava and tephra during the ~3500 BP fissure eruption. We present geochemical, petrologic and geologic observations, including a high-resolution three-dimensional scan of the system that indicate the dike intersected, eroded and assimilated unconsolidated tephra from the buried cinder cone, thus excavating a region along the dike, allowing for future slumping and cave formation. Two petrographically distinct populations of plagioclase phenocrysts are present in the system: a population of smaller (maximum length 1 mm) acicular phenocrysts and a population of larger (maximum length 10 mm) tabular phenocrysts that is commonly broken and displays disequilibrium sieve textures. The acicular plagioclase crystals are present in the dike and lavas while the tabular crystals are in these units and the buried tephra. An intrusion that appears not to have interacted with the tephra has only acicular plagioclase. This suggests that a magma crystallizing a single acicular population of plagioclase intruded the cinder cone and rapidly assimilated the tephra, incorporating the tabular population of phenocrysts from the cone. Petrographic thin-sections of lavas sampled near the vent show undigested fragments of tephra from

  16. Measuring Gases Using Drones at Turrialba Volcano, Costa Rica

    Science.gov (United States)

    Stix, J.; Alan, A., Jr.; Corrales, E.; D'Arcy, F.; de Moor, M. J.; Diaz, J. A.

    2016-12-01

    We are currently developing a series of drones and associated instrumentation to study Turrialba volcano in Costa Rica. This volcano has shown increasing activity during the last 20 years, and the volcano is currently in a state of heightened unrest as exemplified by recent explosive activity in May-August 2016. The eruptive activity has made the summit area inaccessible to normal gas monitoring activities, prompting development of new techniques to measure gas compositions. We have been using two drones, a DJI Spreading Wings S1000 octocopter and a Turbo Ace Matrix-i quadcopter, to airlift a series of instruments to measure volcanic gases in the plume of the volcano. These instruments comprise optical and electrochemical sensors to measure CO2, SO2, and H2S concentrations which are considered the most significant species to help forecast explosive eruptions and determine the relative proportions of magmatic and hydrothermal components in the volcanic gas. Additionally, cameras and sensors to measure air temperature, relative humidity, atmospheric pressure, and GPS location are included in the package to provide meteorological and geo-referenced information to complement the concentration data and provide a better picture of the volcano from a remote location. The integrated payloads weigh 1-2 kg, which can typically be flown by the drones in 10-20 minutes at altitudes of 2000-4000 meters. Preliminary tests at Turrialba in May 2016 have been very encouraging, and we are in the process of refining both the drones and the instrumentation packages for future flights. Our broader goals are to map gases in detail with the drones in order to make flux measurements of each species, and to apply this approach at other volcanoes.

  17. Investigation of the Dashigil mud volcano (Azerbaijan) using beryllium-10

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.J., E-mail: kjkim@kigam.re.kr [Korea Geological Research Division, Korea Institute of Geoscience and Mineral Resources, Daejeon 305-350 (Korea, Republic of); Baskaran, M.; Jweda, J. [Department of Geology, Wayne State University, Detroit, MI 48202 (United States); Feyzullayev, A.A.; Aliyev, C. [Geology Institute of the Azerbaijan National Academy of Sciences (ANAS), Baku, AZ 1143 (Azerbaijan); Matsuzaki, H. [MALT, University of Tokyo, Tokyo (Japan); Jull, A.J.T. [NSF Arizona AMS Lab, University of Arizona, AZ 85721 (United States)

    2013-01-15

    We collected and analyzed five sediments from three mud volcano (MV) vents and six suspended and bottom sediment samples from the adjoining river near the Dashgil mud volcano in Azerbaijan for {sup 10}Be. These three MV are found among the 190 onshore and >150 offshore MV in this region which correspond to the western flank of the South Caspian depression. These MVs overlie the faulted and petroleum-bearing anticlines. The {sup 10}Be concentrations and {sup 10}Be/{sup 9}Be ratios are comparable to the values reported for mud volcanoes in Trinidad Island. It appears that the stable Be concentrations in Azerbaijan rivers are not perturbed by anthropogenic effects and are comparable to the much older sediments (mud volcano samples). The {sup 10}Be and {sup 9}Be concentrations in our river sediments are compared to the global data set and show that the {sup 10}Be values found for Kura River are among the lowest of any river for which data exist. We attribute this low {sup 10}Be concentration to the nature of surface minerals which are affected by the residual hydrocarbon compounds that occur commonly in the study area in particular and Azerbaijan at large. The concentrations of {sup 40}K and U-Th-series radionuclides ({sup 234}Th, {sup 210}Pb, {sup 226}Ra, and {sup 228}Ra) indicate overall homogeneity of the mud volcano samples from the three different sites. Based on the {sup 10}Be concentrations of the mud volcano samples, the age of the mud sediments could be at least as old as 4 myr.

  18. A generic model for the shallow velocity structure of volcanoes

    Science.gov (United States)

    Lesage, Philippe; Heap, Michael J.; Kushnir, Alexandra

    2018-05-01

    The knowledge of the structure of volcanoes and of the physical properties of volcanic rocks is of paramount importance to the understanding of volcanic processes and the interpretation of monitoring observations. However, the determination of these structures by geophysical methods suffers limitations including a lack of resolution and poor precision. Laboratory experiments provide complementary information on the physical properties of volcanic materials and their behavior as a function of several parameters including pressure and temperature. Nevertheless combined studies and comparisons of field-based geophysical and laboratory-based physical approaches remain scant in the literature. Here, we present a meta-analysis which compares 44 seismic velocity models of the shallow structure of eleven volcanoes, laboratory velocity measurements on about one hundred rock samples from five volcanoes, and seismic well-logs from deep boreholes at two volcanoes. The comparison of these measurements confirms the strong variability of P- and S-wave velocities, which reflects the diversity of volcanic materials. The values obtained from laboratory experiments are systematically larger than those provided by seismic models. This discrepancy mainly results from scaling problems due to the difference between the sampled volumes. The averages of the seismic models are characterized by very low velocities at the surface and a strong velocity increase at shallow depth. By adjusting analytical functions to these averages, we define a generic model that can describe the variations in P- and S-wave velocities in the first 500 m of andesitic and basaltic volcanoes. This model can be used for volcanoes where no structural information is available. The model can also account for site time correction in hypocenter determination as well as for site and path effects that are commonly observed in volcanic structures.

  19. Constraints on the geomorphological evolution of the nested summit craters of Láscar volcano from high spatio-temporal resolution TerraSAR-X interferometry

    Science.gov (United States)

    Richter, Nicole; Salzer, Jacqueline Tema; de Zeeuw-van Dalfsen, Elske; Perissin, Daniele; Walter, Thomas R.

    2018-03-01

    Small-scale geomorphological changes that are associated with the formation, development, and activity of volcanic craters and eruptive vents are often challenging to characterize, as they may occur slowly over time, can be spatially localized, and difficult, or dangerous, to access. Using high-spatial and high-temporal resolution synthetic aperture radar (SAR) imagery collected by the German TerraSAR-X (TSX) satellite in SpotLight mode in combination with precise topographic data as derived from Pléiades-1A satellite data, we investigate the surface deformation within the nested summit crater system of Láscar volcano, Chile, the most active volcano of the central Andes. Our aim is to better understand the structural evolution of the three craters that comprise this system, to assess their physical state and dynamic behavior, and to link this to eruptive activity and associated hazards. Using multi-temporal SAR interferometry (MT-InSAR) from ascending and descending orbital geometries, we retrieve the vertical and east-west components of the displacement field. This time series indicates constant rates of subsidence and asymmetric horizontal displacements of all summit craters between June 2012 and July 2014, as well as between January 2015 and March 2017. The vertical and horizontal movements that we observe in the central crater are particularly complex and cannot be explained by any single crater formation mechanism; rather, we suggest that short-term activities superimposed on a combination of ongoing crater evolution processes, including gravitational slumping, cooling and compaction of eruption products, as well as possible piston-like subsidence, are responsible for the small-scale geomorphological changes apparent in our data. Our results demonstrate how high-temporal resolution synthetic aperture radar interferometry (InSAR) time series can add constraints on the geomorphological evolution and structural dynamics of active crater and vent systems at

  20. Continuation calculus

    Directory of Open Access Journals (Sweden)

    Bram Geron

    2013-09-01

    Full Text Available Programs with control are usually modeled using lambda calculus extended with control operators. Instead of modifying lambda calculus, we consider a different model of computation. We introduce continuation calculus, or CC, a deterministic model of computation that is evaluated using only head reduction, and argue that it is suitable for modeling programs with control. It is demonstrated how to define programs, specify them, and prove them correct. This is shown in detail by presenting in CC a list multiplication program that prematurely returns when it encounters a zero. The correctness proof includes termination of the program. In continuation calculus we can model both call-by-name and call-by-value. In addition, call-by-name functions can be applied to call-by-value results, and conversely.