WorldWideScience

Sample records for monitoring volcanic activity

  1. Jovian Dust Streams: A monitor of Io's volcanic plume activity

    CERN Document Server

    Krüger, H; Horányi, M; Graps, A L; Kempf, S; Srama, R; Moragas-Klostermeyer, G; Moissl, R; Johnson, T V; Grün, E; Krueger, Harald; Geissler, Paul; Horanyi, Mihaly; Graps, Amara L.; Kempf, Sascha; Srama, Ralf; Moragas-Klostermeyer, Georg; Moissl, Richard; Johnson, Torrence V.; Gruen, Eberhard

    2003-01-01

    Streams of high speed dust particles originate from Jupiter's innermost Galilean moon Io. After release from Io, the particles collect electric charges in the Io plasma torus, gain energy from the co-rotating electric field of Jupiter's magnetosphere, and leave the Jovian system into interplanetary space with escape speeds over $\\rm 200 km s^{-1}$. Galileo, which was the first orbiter spacecraft of Jupiter, has continuously monitored the dust streams during 34 revolutions about the planet between 1996 and 2002. The observed dust fluxes exhibit large orbit-to-orbit variability due to systematic and stochastic changes. After removal of the systematic variations, the total dust emission rate of Io has been calculated. It varies between $10^{-3}$ and $\\mathrm{10} \\rm kg s^{-1}$, and is typically in the range of 0.1 to $\\rm 1 kg s^{-1}$. We compare the dust emission rate with other markers of volcanic activity on Io like large-area surface changes caused by volcanic deposits and sightings of volcanic plumes.

  2. GRID based Thermal Images Processing for volcanic activity monitoring

    Science.gov (United States)

    Mangiagli, S.; Coco, S.; Drago, L.; Laudani, A.,; Lodato, L.; Pollicino, G.; Torrisi, O.

    2009-04-01

    Since 2001, the Catania Section of the National Institute of Geophysics and Volcanology (INGV) has been running the video stations recording the volcanic activity of Mount Etna, Stromboli and the Fossa Crater of Vulcano island. The video signals of 11 video cameras (seven operating in the visible band and four in infrared) are sent in real time to INGV Control Centre where they are visualized on monitors and archived on a dedicated NAS storage. The video surveillance of the Sicilian volcanoes, situated near to densely populated areas, helps the volcanologists providing the Civil Protection authorities with updates in real time on the on-going volcanic activity. In particular, five video cameras are operating on Mt. Etna and they record the volcano from the south and east sides 24 hours a day. During emergencies, mobile video stations may also be used to better film the most important phases of the activity. Single shots are published on the Catania Section intranet and internet websites. On June 2006 a A 40 thermal camera was installed in Vulcano La Fossa Crater. The location was in the internal and opposite crater flank (S1), 400 m distant from the fumarole field. The first two-year of data on temperature distribution frequency were recorded with this new methodology of acquisition, and automatically elaborated by software at INGV Catania Section. In fact a dedicated software developed in IDL, denominated Volcano Thermo Analysis (VTA), was appositely developed in order to extract a set of important features, able to characterize with a good approssimation the volcanic activity. In particular the program first load and opportunely convert the thermal images, then according to the Region Of Interest (ROI) and the temperature ranges defined by the user provide to automatic spatial and statistic analysis. In addition the VTA is able to analysis all the temporal series of images available in order to achieve the time-event analysis and the dynamic of the volcanic

  3. FRAME DESIGN OF REMOTE SENSING MONITORING FOR VOLCANIC ACTIVITIES IN CHANGBAI MOUNTAINS

    Institute of Scientific and Technical Information of China (English)

    BO Li-qun; ZHAO Yun-ping; HUA Ren-kui

    2003-01-01

    Volcanic eruption is one of the most serious geological disasters, however, a host of facts have proven that the Changbai Mountains volcano is a modem dormant one and has ever erupted disastrously. With the rapid development of remote sensing technology, space monitoring of volcanic activities has already become possible, particularly in the application of thermal infrared remote sensing. The paper, through the detailed analysis of geothermal anomaly factors such as heat radiation, heat conduction and convection, depicts the monitoring principles by which volcano activities would be monitored efficiently and effectively. Reasons for abrupt geothermal anomaly are mainly analyzed, and transmission mechanism of geothermal anomaly in the volcanic regions is explained. Also, a variety of noises disturbing the transmission of normal geothermal anomaly are presented. Finally, some clues are given based on discussing thermal infrared remote sensing monitoring mechanism toward the volcanic areas.

  4. 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.

  5. Chemistry of ash-leachates to monitor volcanic activity: An application to Popocatepetl volcano, central Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Armienta, M.A., E-mail: victoria@geofisica.unam.mx [Universidad Nacional Autonoma de Mexico, Instituto de Geofisica, Circuito Exterior, C.U., Mexico 04510 D.F. (Mexico); De la Cruz-Reyna, S. [Universidad Nacional Autonoma de Mexico, Instituto de Geofisica, Circuito Exterior, C.U., Mexico 04510 D.F. (Mexico); Soler, A. [Grup de Mineralogia Aplicada i Medi Ambient, Dep. Cristal.lografia, Mineralogia i Diposits Minerals, Fac. Geologia, Universidad de Barcelona (Spain); Cruz, O.; Ceniceros, N.; Aguayo, A. [Universidad Nacional Autonoma de Mexico, Instituto de Geofisica, Circuito Exterior, C.U., Mexico 04510 D.F. (Mexico)

    2010-08-15

    Monitoring volcanic activity and assessing volcanic risk in an on-going eruption is a problem that requires the maximum possible independent data to reduce uncertainty. A quick, relatively simple and inexpensive method to follow the development of an eruption and to complement other monitoring parameters is the chemical analysis of ash leachates, particularly in the case of eruptions related to dome emplacement. Here, the systematic analysis of SO{sub 4}{sup 2-}, Cl{sup -} and F{sup -} concentrations in ash leachates is proposed as a valuable tool for volcanic activity monitoring. However, some results must be carefully assessed, as is the case for S/Cl ratios, since eruption of hydrothermally altered material may be confused with degassing of incoming magma. Sulfur isotopes help to identify SO{sub 4} produced by hydrothermal processes from magmatic SO{sub 2}. Lower S isotopic values correlated with higher F{sup -} percentages represent a better indicator of fresh magmatic influence that may lead to stronger eruptions and emplacement of new lava domes. Additionally, multivariate statistical analysis helps to identify different eruption characteristics, provided that the analyses are made over a long enough time to sample different stages of an eruption.

  6. The roar of Yasur: Handheld audio recorder monitoring of Vanuatu volcanic vent activity

    Science.gov (United States)

    Lorenz, Ralph D.; Turtle, Elizabeth P.; Howell, Robert; Radebaugh, Jani; Lopes, Rosaly M. C.

    2016-08-01

    We describe how near-field audio recording using a pocket digital sound recorder can usefully document volcanic activity, demonstrating the approach at Yasur, Vanuatu in May 2014. Prominent emissions peak at 263 Hz, interpreted as an organ-pipe mode. High-pass filtering was found to usefully discriminate volcano vent noise from wind noise, and autocorrelation of the high pass acoustic power reveals a prominent peak in exhalation intervals of 2.5, 4 and 8 s, with a number of larger explosive events at 200 s intervals. We suggest that this compact and inexpensive audio instrumentation can usefully supplement other field monitoring such as seismic or infrasound. A simple estimate of acoustic power interpreted with a dipole jet noise model yielded vent velocities too low to be compatible with pyroclast emission, suggesting difficulties with this approach at audio frequencies (perhaps due to acoustic absorption by volcanic gases).

  7. Infrasound Monitoring of the Volcanic Activities of Japanese Volcanoes in Korea

    Science.gov (United States)

    Lee, H. I.; Che, I. Y.; Shin, J. S.

    2015-12-01

    Since 1999 when our first infrasound array station(CHNAR) has been installed at Cheolwon, Korea Institute of Geoscience and Mineral Resources(KIGAM) is continuously observing infrasound signals with an infrasound array network, named KIN(Korean Infrasound Network). This network is comprised of eight seismo-acoustic array stations(BRDAR, YPDAR, KMPAR, CHNAR, YAGAR, KSGAR, ULDAR, TJIAR). The aperture size of the smallest array is 300m and the largest is about 1.4km. The number of infrasound sensors are between 4(TJIAR) and 18(YAGAR), and 1~5 seismometers are collocated with infrasound sensors. Many interesting infrasound signals associated with different type of sources, such as blasting, large earthquake, bolide, volcanic explosion are detected by KIN in the past 15 years. We have analyzed the infrasound signals possibly associated with the japanese volcanic explosions with reference to volcanic activity report published by Japanese Meteorological Agency. Analysis results of many events, for example, Asama volcano explosion in 2004 and Shinmoe volcano in 2011, are well matched with the official report. In some cases, however, corresponding infrasound signals are not identified. By comparison of the infrasound signals from different volcanoes, we also found that the characteristics of signals are distinguishing. It may imply that the specific volcano has its own unique fingerprint in terms of infrasound signal. It might be investigated by long-term infrasound monitoring for a specific volcano as a ground truth generating repetitive infrasound signal.

  8. Geochemical monitoring of volcanic lakes. A generalized box model for active crater lakes

    Directory of Open Access Journals (Sweden)

    Franco Tassi

    2011-06-01

    Full Text Available

    In the past, variations in the chemical contents (SO42−, Cl−, cations of crater lake water have not systematically demonstrated any relationships with eruptive activity. Intensive parameters (i.e., concentrations, temperature, pH, salinity should be converted into extensive parameters (i.e., fluxes, changes with time of mass and solutes, taking into account all the internal and external chemical–physical factors that affect the crater lake system. This study presents a generalized box model approach that can be useful for geochemical monitoring of active crater lakes, as highly dynamic natural systems. The mass budget of a lake is based on observations of physical variations over a certain period of time: lake volume (level, surface area, lake water temperature, meteorological precipitation, air humidity, wind velocity, input of spring water, and overflow of the lake. This first approach leads to quantification of the input and output fluxes that contribute to the actual crater lake volume. Estimating the input flux of the "volcanic" fluid (Qf- kg/s –– an unmeasurable subsurface parameter –– and tracing its variations with time is the major focus during crater lake monitoring. Through expanding the mass budget into an isotope and chemical budget of the lake, the box model helps to qualitatively characterize the fluids involved. The (calculated Cl− content and dD ratio of the rising "volcanic" fluid defines its origin. With reference to continuous monitoring of crater lakes, the present study provides tips that allow better calculation of Qf in the future. At present, this study offers the most comprehensive and up-to-date literature review on active crater lakes.

  9. Monitoring volcanic activity with satellite remote sensing to reduce aviation hazard and mitigate the risk: application to the North Pacific

    Science.gov (United States)

    Webley, P. W.; Dehn, J.

    2012-12-01

    Volcanic activity across the North Pacific (NOPAC) occurs on a daily basis and as such monitoring needs to occur on a 24 hour, 365 days a year basis. The risk to the local population and aviation traffic is too high for this not to happen. Given the size and remoteness of the NOPAC region, satellite remote sensing has become an invaluable tool to monitor the ground activity from the regions volcanoes as well as observe, detect and analyze the volcanic ash clouds that transverse across the Pacific. Here, we describe the satellite data collection, data analysis, real-time alert/alarm systems, observational database and nearly 20-year archive of both automated and manual observations of volcanic activity. We provide examples of where satellite remote sensing has detected precursory activity at volcanoes, prior to the volcanic eruption, as well as different types of eruptive behavior that can be inferred from the time series data. Additionally, we illustrate how the remote sensing data be used to detect volcanic ash in the atmosphere, with some of the pro's and con's to the method as applied to the NOPAC, and how the data can be used with other volcano monitoring techniques, such as seismic monitoring and infrasound, to provide a more complete understanding of a volcanoes behavior. We focus on several large volcanic events across the region, since our archive started in 1993, and show how the system can detect both these large scale events as well as the smaller in size but higher in frequency type events. It's all about how to reduce the risk, improve scenario planning and situational awareness and at the same time providing the best and most reliable hazard assessment from any volcanic activity.

  10. VEPP Exercise: Volcanic Activity and Monitoring of Pu`u `O`o, Kilauea Volcano, Hawaii

    Science.gov (United States)

    Rodriguez, L. A.

    2010-12-01

    A 10-week project will be tested during the Fall semester 2010, for a Volcanic Hazards elective course, for undergraduate Geology students of the University of Puerto Rico at Mayaguez. This exercise was developed during the Volcanoes Exploration Project: Pu`u `O`o (VEPP) Workshop, held on the Big Island of Hawaii in July 2010. For the exercise the students will form groups (of 2-4 students), and each group will be assigned a monitoring technique or method, among the following: seismic (RSAM data), deformation (GPS and tilt data), observations (webcam and lava flow maps), gas and thermal monitoring. The project is designed for Geology undergraduates who have a background in introductory geology, types of volcanoes and eruptions, magmatic processes, characteristics of lava flows, and other related topics. It is divided in seven tasks, starting with an introduction and demonstration of the VEPP website and the VALVE3 software, which is used to access monitoring data from the current eruption of Pu`u `O`o, Kilauea volcano, Hawaii. The students will also familiarize themselves with the history of Kilauea volcano and its current eruption. At least weekly the groups will acquire data (mostly near-real-time) from the different monitoring techniques, in the form of time series, maps, videos, and images, in order to identify trends in the data. The groups will meet biweekly in the computer laboratory to work together in the analysis and interpretation of the data, with the support of the instructor. They will give reports on the progress of the exercise, and will get feedback from the instructor and from the other expert groups. All groups of experts will relate their findings to the recent and current activity of Kilauea volcano, and the importance of their specific type of monitoring. The activity will culminate with a written report and an oral presentation. The last task of the project consists of a wrap-up volcano monitoring exercise, in which the students will

  11. Can we detect, monitor, and characterize volcanic activity using 'off the shelf' webcams and low-light cameras?

    Science.gov (United States)

    Harrild, M.; Webley, P. W.; Dehn, J.

    2015-12-01

    The ability to detect and monitor precursory events, thermal signatures, and ongoing volcanic activity in near-realtime is an invaluable tool. Volcanic hazards often range from low level lava effusion to large explosive eruptions, easily capable of ejecting ash to aircraft cruise altitudes. Using ground based remote sensing to detect and monitor this activity is essential, but the required equipment is often expensive and difficult to maintain, which increases the risk to public safety and the likelihood of financial impact. Our investigation explores the use of 'off the shelf' cameras, ranging from computer webcams to low-light security cameras, to monitor volcanic incandescent activity in near-realtime. These cameras are ideal as they operate in the visible and near-infrared (NIR) portions of the electromagnetic spectrum, are relatively cheap to purchase, consume little power, are easily replaced, and can provide telemetered, near-realtime data. We focus on the early detection of volcanic activity, using automated scripts that capture streaming online webcam imagery and evaluate each image according to pixel brightness, in order to automatically detect and identify increases in potentially hazardous activity. The cameras used here range in price from 0 to 1,000 and the script is written in Python, an open source programming language, to reduce the overall cost to potential users and increase the accessibility of these tools, particularly in developing nations. In addition, by performing laboratory tests to determine the spectral response of these cameras, a direct comparison of collocated low-light and thermal infrared cameras has allowed approximate eruption temperatures to be correlated to pixel brightness. Data collected from several volcanoes; (1) Stromboli, Italy (2) Shiveluch, Russia (3) Fuego, Guatemala (4) Popcatépetl, México, along with campaign data from Stromboli (June, 2013), and laboratory tests are presented here.

  12. Volcview: A Web-Based Platform for Satellite Monitoring of Volcanic Activity and Eruption Response

    Science.gov (United States)

    Schneider, D. J.; Randall, M.; Parker, T.

    2014-12-01

    The U.S. Geological Survey (USGS), in cooperation with University and State partners, operates five volcano observatories that employ specialized software packages and computer systems to process and display real-time data coming from in-situ geophysical sensors and from near-real-time satellite sources. However, access to these systems both inside and from outside the observatory offices are limited in some cases by factors such as software cost, network security, and bandwidth. Thus, a variety of Internet-based tools have been developed by the USGS Volcano Science Center to: 1) Improve accessibility to data sources for staff scientists across volcano monitoring disciplines; 2) Allow access for observatory partners and for after-hours, on-call duty scientists; 3) Provide situational awareness for emergency managers and the general public. Herein we describe VolcView (volcview.wr.usgs.gov), a freely available, web-based platform for display and analysis of near-real-time satellite data. Initial geographic coverage is of the volcanoes in Alaska, the Russian Far East, and the Commonwealth of the Northern Mariana Islands. Coverage of other volcanoes in the United States will be added in the future. Near-real-time satellite data from NOAA, NASA and JMA satellite systems are processed to create image products for detection of elevated surface temperatures and volcanic ash and SO2 clouds. VolcView uses HTML5 and the canvas element to provide image overlays (volcano location and alert status, annotation, and location information) and image products that can be queried to provide data values, location and measurement capabilities. Use over the past year during the eruptions of Pavlof, Veniaminof, and Cleveland volcanoes in Alaska by the Alaska Volcano Observatory, the National Weather Service, and the U.S. Air Force has reinforced the utility of shared situational awareness and has guided further development. These include overlay of volcanic cloud trajectory and

  13. Eighteen years of geochemical monitoring at the oceanic active volcanic island of El Hierro (Canary Islands, Spain)

    Science.gov (United States)

    Asensio-Ramos, María; Alonso, Mar; Sharp, Emerson; Woods, Hannah; Barrancos, José; Pérez, Nemesio M.

    2016-04-01

    We report herein the latest results of a diffuse CO2 efflux survey at El Hierro volcanic system carried out during the summer period of 2015 to constrain the total CO2 output from the studied area a during post-eruptive period. El Hierro Island (278 km2) is the youngest and the SW-most of the Canary Islands. On July 16, 2011, a seismic-volcanic crisis started with the occurrence of more than 11,900 seismic events and significant deformation along the island. On October 10, 2011, the dominant character of seismicity changed dramatically from discrete earthquakes to continuous tremor, a clear indication that magma was rapidly approaching the surface immediately before the onset of the eruption, October 12. Eruption was declared over on 5 March, 2012. In order to monitor the volcanic activity of El Hierro Island, from 1998 to 2015 diffuse CO2 emission studies have been performed at El Hierro volcanic system in a yearly basis (˜600 observation sites) according to the accumulation chamber method. Spatial distribution maps were constructed following the sequential Gaussian simulation (sGs) procedure. To quantify the total CO2 emission from the studied area, 100 simulations for each survey have been performed. During the eruption period, soil CO2 efflux values range from non-detectable (˜0.5 g m-2 d-1) up to 457 g m-2 d-1, reaching in November 27, 2011, the maximum CO2 output estimated value of all time series, 2,398 t d-1, just before the episodes of maximum degassing observed as vigorous bubbling at the sea surface and an increment in the amplitude of the tremor signal. During the 2015 survey, soil CO2 efflux values ranged from non-detectable up to 41 g m-2 d-1. The spatial distribution of diffuse CO2 emission values seemed to be controlled by the main volcano structural features of the island. The total diffuse CO2 output released to atmosphere was estimated at 575 ± 24 t d-1, value slightly higher that the background CO2 emission estimated at 422 t d-1 (Melián et

  14. Seismicity and active tectonics at Coloumbo Reef (Aegean Sea, Greece): Monitoring an active volcano at Santorini Volcanic Center using a temporary seismic network

    Science.gov (United States)

    Dimitriadis, I.; Karagianni, E.; Panagiotopoulos, D.; Papazachos, C.; Hatzidimitriou, P.; Bohnhoff, M.; Rische, M.; Meier, T.

    2009-02-01

    The volcanic center of Santorini Island is the most active volcano of the southern Aegean volcanic arc. Α dense seismic array consisting of fourteen portable broadband seismological stations has been deployed in order to monitor and study the seismo-volcanic activity at the broader area of the Santorini volcanic center between March 2003 and September 2003. Additional recordings from a neighbouring larger scale temporary network (CYCNET) were also used for the relocation of more than 240 earthquakes recorded by both arrays. A double-difference relocation technique was used, in order to obtain optimal focal parameters for the best-constrained earthquakes. The results indicate that the seismic activity of the Santorini volcanic center is strongly associated with the tectonic regime of the broader Southern Aegean Sea area as well as with the volcanic processes. The main cluster of the epicenters is located at the Coloumbo Reef, a submarine volcano of the volcanic system of Santorini Islands. A smaller cluster of events is located near the Anydros Islet, aligned in a NE-SW direction, running almost along the main tectonic feature of the area under study, the Santorini-Amorgos Fault Zone. In contrast, the main Santorini Island caldera is characterized by the almost complete absence of seismicity. This contrast is in very good agreement with recent volcanological and marine studies, with the Coloumbo volcanic center showing an intense high-temperature hydrothermal activity, in comparison to the corresponding low-level activity of the Santorini caldera. The high-resolution hypocentral relocations present a clear view of the volcanic submarine structure at the Coloumbo Reef, showing that the main seismic activity is located within a very narrow vertical column, mainly at depths between 6 and 9 km. The focal mechanisms of the best-located events show that the cluster at the Coloumbo Reef is associated with the "Kameni-Coloumbo Fracture Zone", which corresponds to the

  15. System of Volcanic activity

    Directory of Open Access Journals (Sweden)

    P. HÉDERVARI

    1972-06-01

    Full Text Available A comparison is made among the systems of B. G.
    Escher (3, of R. W. van Bemmelen (1 and that of the author (4. In this
    connection, on the basis of Esclier's classification, the terms of "constructiv
    e " and "destructive" eruptions are introduced into the author's system and
    at the same time Escher's concept on the possible relation between the depth
    of magma-chamber and the measure of the gas-pressure is discussed briefly.
    Three complementary remarks to the first paper (4 011 the subject of system
    of volcanic activity are added.

  16. Satellite observations of fumarole activity at Aluto volcano, Ethiopia: Implications for geothermal monitoring and volcanic hazard

    Science.gov (United States)

    Braddock, Mathilde; Biggs, Juliet; Watson, Iain M.; Hutchison, William; Pyle, David M.; Mather, Tamsin A.

    2017-07-01

    Fumaroles are the surface manifestation of hydrothermal circulation and can be influenced by magmatic, hydrothermal, hydrological and tectonic processes. This study investigates the temporal changes in fumarole temperatures and spatial extent on Aluto, a restless volcano in the Main Ethiopian Rift (MER), in order to better understand the controls on fluid circulation and the interaction between the magmatic and hydrothermal systems. Thermal infrared (TIR) satellite images, acquired by the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) over the period of 2004 to 2016, are used to generate time series of the fumarole temperatures and areas. The thermal anomalies identified in the ASTER images coincide with known fumaroles with temperatures > 80 °C and are located on or close to fault structures, which provide a pathway for the rising fluids. Most of the fumaroles, including those along the major zone of hydrothermal upwelling, the Artu Jawe Fault Zone, have pixel-integrated temperature variations of only 2 ± 1.5 °C. The exception are the Bobesa fumaroles located on a hypothesised caldera ring fault which show pixel-integrated temperature changes of up to 9 °C consistent with a delayed response of the hydrothermal system to precipitation. We conclude that fumaroles along major faults are strongly coupled to the magmatic-hydrothermal system and are relatively stable with time, whereas those along shallower structures close to the rift flank are more strongly influenced by seasonal variations in groundwater flow. The use of remote sensing data to monitor the thermal activity of Aluto provides an important contribution towards understanding the behaviour of this actively deforming volcano. This method could be used at other volcanoes around the world for monitoring and geothermal exploration.

  17. Planning the improvement of a seismic network for monitoring active volcanic areas: the experience on Mt. Etna

    Science.gov (United States)

    D'Alessandro, A.; Scarfì, L.; Scaltrito, A.; Di Prima, S.; Rapisarda, S.

    2013-10-01

    Seismology and geodesy are generally seen as the most reliable diagnostic tools for monitoring highly active or erupting volcanoes, like Mt. Etna. From the early 1980's, seismic activity was monitored at Mt. Etna by a permanent seismic network, progressively improved in the following years. This network has been considerably enhanced since 2005 by 24-bit digital stations equipped with broad-band (40 s) sensors. Today, thanks to a configuration of 33 broad-band and 12 short-period stations, we have a good coverage of the volcanic area as well as a high quality of the collected data. In the framework of the VULCAMED project a workgroup of Istituto Nazionale di Geofisica e Vulcanologia has taken on the task of developing the seismic monitoring system, through the installation of other seismic stations. The choice of optimal sites must be clearly made through a careful analysis of the geometry of the existing seismic network. In this paper, we applied the Seismic Network Evaluation through Simulation in order to evaluate the performance of the Etna Seismic Network before and after the addition of the stations in the candidate sites. The main advantage of the adopted method is that we can evaluate the improvement of the network before the actual installation of the stations. Our analysis has permitted to identify some critical issues of the current permanent seismic network related to the lack of stations in the southern sector of the volcano, which is nevertheless affected by a number of seismogenic structures. We have showed that the addition of stations at the candidate sites would greatly extend the coverage of the network to the south by significantly reducing the errors in the hypocenter parameters estimation.

  18. Diffuse H_{2} emission: a useful geochemical tool to monitor the volcanic activity at El Hierro volcano system

    Science.gov (United States)

    Pérez, Nemesio M.; Melián, Gladys; González-Santana, Judit; Barrancos, José; Padilla, Germán; Rodríguez, Fátima; Padrón, Eleazar; Hernández, Pedro A.

    2016-04-01

    The occurrence of interfering processes affecting reactive gases as CO2 during its ascent from magmatic bodies or hydrothermal systems toward the surface environment hinders the interpretation of their enrichments in the soil atmosphere and fluxes for volcano monitoring purposes (Marini and Gambardella, 2005). These processes include gas scrubbing by ground-waters and interaction with rocks, decarbonatation processes, biogenic production, etc. Within the rest of the soil gases, particularly interest has been addressed to light and highly mobile gases. They offer important advantages for the detection of vertical permeability structures, because their interaction with the surrounding rocks or fluids during the ascent toward the surface is minimum. H2 is one of the most abundant trace species in volcano-hydrothermal systems and is a key participant in many redox reactions occurring in the hydrothermal reservoir gas (Giggenbach, 1987). Although H2 can be produced in soils by N2-fixing and fertilizing bacteria, soils are considered nowadays as sinks of molecular hydrogen (Smith-Downey et al., 2006). Because of its chemical and physical characteristics, H2 generated within the crust moves rapidly and escapes to the atmosphere. These characteristics make H2 one of the best geochemical indicators of magmatic and geothermal activity at depth. El Hierro is the youngest and the SW-most of the Canary Islands and the scenario of the last volcanic eruption of the archipelago, a submarine eruption that took place 2 km off the southern coast of the island from October 2011 to March 2012. Since at El Hierro Island there are not any surface geothermal manifestations (fumaroles, etc), we have focused our studies on soil degassing surveys. Here we show the results of soil H2 emission surveys that have been carried out regularly since mid-2012. Soil gas samples were collected in ˜600 sites selected based on their accessibility and geological criteria. Soil gases were sampled at ˜40

  19. Monitoring of low-energy seismic activity in Elbrus volcanic area with the use of underground seismic array

    Science.gov (United States)

    Kovalevsky, V.; Sobisevitch, A.

    2012-04-01

    Results of experiment with underground seismic array for studying low-energy seismic activity in the Elbrus volcanic area are presented. Linear seismic array of 2.5 km aperture is created in the tunnel of Baksan neutrino observatory. Horizontal tunnel of 4.3 km length is drilled in the mount Andyrchi at a distance of 20 km from Elbrus volcano. Array includes 6 three-component seismic sensors with 24-byte recorders installed with 500 m interval one from another along the tunnel. Underground seismic array is the new instrument of geophysical observatory organized for studies of geophysical processes in the Elbrus volcanic area. The observatory equipped with modern geophysical instruments including broadband tri-axial seismometers, quartz tilt-meters, magnetic variometers, geo-acoustic sensors, hi-precision distributed thermal sensors and gravimeters. The initial analysis of seismic signals recorded by seismic array allows us to detect low-energy seismic activity in the Elbrus volcanic area beginning from the distance of 3-5 km (the faults in a vicinity of mount Andyrchi) up to 15-25 km (area of Elbrus volcano). The regional micro-earthquakes with magnitude 1-2 at the distances 50-100 km was also recorded. 2.5 km aperture of the underground linear seismic array make it possible to determine with high accuracy hypocenters of local seismic events associated with geodynamic of volcanic magmatic structures and to realize seismo-emission tomography of the active zones of Elbrus volcano.

  20. Combination of SAR remote sensing and GIS for monitoring subglacial volcanic activity – recent results from Vatnajökull ice cap (Iceland

    Directory of Open Access Journals (Sweden)

    U. Münzer

    2007-11-01

    Full Text Available This paper presents latest results from the combined use of SAR (Synthetic Aperture Radar remote sensing and GIS providing detailed insights into recent volcanic activity under Vatnajökull ice cap (Iceland. Glaciers atop active volcanoes pose a constant potential danger to adjacent inhabited regions and infrastructure. Besides the usual volcanic hazards (lava flows, pyroclastic clouds, tephra falls, etc., the volcano-ice interaction leads to enormous meltwater torrents (icelandic: jökulhlaup, devastating large areas in the surroundings of the affected glacier. The presented monitoring strategy addresses the three crucial questions: When will an eruption occur, where is the eruption site and which area is endangered by the accompanying jökulhlaup. Therefore, sufficient early-warning and hazard zonation for future subglacial volcanic eruptions becomes possible, as demonstrated for the Bardárbunga volcano under the northern parts of Vatnajökull. Seismic activity revealed unrest at the northern flanks of Bardárbunga caldera at the end of September 2006. The exact location of the corresponding active vent and therefore a potentially eruptive area could be detected by continuous ENVISAT-ASAR monitoring. With this knowledge a precise prediction of peri-glacial regions prone to a devastating outburst flood accompanying a possible future eruption is possible.

  1. Io. [theories concerning volcanic activity

    Science.gov (United States)

    Johnson, T. V.; Soderblom, L. A.

    1983-01-01

    A report on the continuing investigation of Io is presented. Gravitational resonance is discussed as the cause of Io's volcanism, and the volcanic activity is explained in terms of sulfur chemistry. Theories concerning the reasons for the two main types of volcanic eruptions on Io are advanced and correlated with geographical features of the satellite. The sulfur and silicate models of the calderas are presented, citing the strengths and weaknesses of each. Problems of the gravitational resonance theory of Io's heat source are then described. Finally, observations of Io planned for the Galileo mission are summarized.

  2. Monitoring and forecasting Etna volcanic plumes

    Directory of Open Access Journals (Sweden)

    S. Scollo

    2009-09-01

    Full Text Available In this paper we describe the results of a project ongoing at the Istituto Nazionale di Geofisica e Vulcanologia (INGV. The objective is to develop and implement a system for monitoring and forecasting volcanic plumes of Etna. Monitoring is based at present by multispectral infrared measurements from the Spin Enhanced Visible and Infrared Imager on board the Meteosat Second Generation geosynchronous satellite, visual and thermal cameras, and three radar disdrometers able to detect ash dispersal and fallout. Forecasting is performed by using automatic procedures for: i downloading weather forecast data from meteorological mesoscale models; ii running models of tephra dispersal, iii plotting hazard maps of volcanic ash dispersal and deposition for certain scenarios and, iv publishing the results on a web-site dedicated to the Italian Civil Protection. Simulations are based on eruptive scenarios obtained by analysing field data collected after the end of recent Etna eruptions. Forecasting is, hence, supported by plume observations carried out by the monitoring system. The system was tested on some explosive events occurred during 2006 and 2007 successfully. The potentiality use of monitoring and forecasting Etna volcanic plumes, in a way to prevent threats to aviation from volcanic ash, is finally discussed.

  3. Change detection and characterization of volcanic activity using ground based low-light and near infrared cameras to monitor incandescence and thermal signatures

    Science.gov (United States)

    Harrild, Martin; Webley, Peter; Dehn, Jonathan

    2015-04-01

    Knowledge and understanding of precursory events and thermal signatures are vital for monitoring volcanogenic processes, as activity can often range from low level lava effusion to large explosive eruptions, easily capable of ejecting ash up to aircraft cruise altitudes. Using ground based remote sensing techniques to monitor and detect this activity is essential, but often the required equipment and maintenance is expensive. Our investigation explores the use of low-light cameras to image volcanic activity in the visible to near infrared (NIR) portion of the electromagnetic spectrum. These cameras are ideal for monitoring as they are cheap, consume little power, are easily replaced and can provide near real-time data. We focus here on the early detection of volcanic activity, using automated scripts, that capture streaming online webcam imagery and evaluate image pixel brightness values to determine relative changes and flag increases in activity. The script is written in Python, an open source programming language, to reduce the overall cost to potential consumers and increase the application of these tools across the volcanological community. In addition, by performing laboratory tests to determine the spectral response of these cameras, a direct comparison of collocated low-light and thermal infrared cameras has allowed approximate eruption temperatures and effusion rates to be determined from pixel brightness. The results of a field campaign in June, 2013 to Stromboli volcano, Italy, are also presented here. Future field campaigns to Latin America will include collaborations with INSIVUMEH in Guatemala, to apply our techniques to Fuego and Santiaguito volcanoes.

  4. Geodetic Monitoring System Operating On Neapolitan Volcanic Area (southern Italy)

    Science.gov (United States)

    Pingue, F.; Ov-Geodesy Team

    The Neapolitan volcanic area is located in the southern sector of the Campanian Plain Graben including three volcanic active structures (Somma-Vesuvius, Campi Flegrei and Ischia). The Somma-Vesuvius complex, placed East of Naples, is a strato-volcano composed by a more ancient apparatus (Mt. Somma) and a younger cone (Mt. Vesu- vius) developed inside Somma caldera. Since last eruption (1944) it is in a quiescent state characterised by a low level seismicity and deformation activity. The Campi Fle- grei, located West of Naples, are a volcanic field inside an older caldera rim. The last eruption, occurred in the 1538, built up the Mt. Nuovo cone. The Campi Flegrei are subject to a slow vertical deformation, called bradyseism. In the 1970-1972 and 1982-1984 they have been affected by two intense episodes of ground upheaval (ac- companied by an intense seismic activity)0, followed by a subsidence phase, slower than uplift and still active. Though such phenomenon has not been followed by erup- tive events, it caused serious damages, emphasizing the high volcanic risk of the phle- grean caldera. The Ischia island, located SW of Naples, has been characterised by a volcanic activity both explosive and effusive, occurred mainly in the last 50,000 years. These events modelled the topography producing fault systems and structures delim- iting the Mt. Epomeo resurgent block. The last eruption has occurred on 1302. After, the dynamics of the island has been characterised by seismic activity (the strongest earthquake occurred on 1883) and by a meaningful subsidence, on the S and NW sec- tors of the island. The concentration of such many active volcanoes in an area with a dense urbanization (about 1,500,000 inhabitants live) needs systematic and contin- uous monitoring of the dynamics. These information are necessary in order to char- acterise eruptive precursors useful for modelling the volcanoes behaviour. Insofar, the entire volcanic Neapolitan area, characterised by a

  5. Electrochemical sensor monitoring of volcanic gases

    Science.gov (United States)

    Roberts, Tjarda; Freshwater, Ray; Oppenheimer, Clive; Saffell, John; Jones, Rod; Griffiths, Paul; Braban, Christine; Mead, Iqbal

    2010-05-01

    Advances in instrumentation have fuelled a recent growth of interest in using portable sensor systems for environmental monitoring of pollution. Developments in wireless technology are enabling such systems to operate remotely and autonomously, generating a wealth of environmental data. We report here on the application of miniature Alphasense electrochemical sensors to the detection and characterisation of gases in volcanic plumes. A highly portable sensor system was developed to operate an array of 6 low cost electrochemical sensors to detect CO, H2, HCl, SO2, H2S and NO2 at 1 Hz. A miniature pump draws air over all sensors simultaneously (i.e. sensors arranged in parallel). The sensor output in these campaigns was logged on PDAs for real-time viewing, and later download (with a view to future data-streaming). The instrument was deployed at a number of volcanoes and was subject to extremely harsh conditions including highly acidic environments, low (Antarctic) temperatures, and transport over rough terrain. Analysis methods are demonstrated that consider calibration, cross-sensitivities of the sensors to multiple gases, differing sensor response times, temperature dependence, and background sensor drift with time. The analysis is applied to a range of plume field-measurements to extract gas concentrations ranging from 100's ppmv to sub-ppmv and to characterise the individual volcano emissions. Applications of similar sensor systems for real-time long-term monitoring of volcanic emissions (which may indicate and ultimately predict eruptive behavior), and UAV and balloon-borne plume sampling are now already being realised. This work focused on demonstrating the application of electrochemical sensors to monitoring of environmental pollution from volcanoes. Other applications for similar sensors include the near-source monitoring of industrial emissions, and of pollutant levels enhanced by traffic emissions in the urban environment.

  6. Cost-effective monitoring of ground motion related to earthquakes, landslides, or volcanic activity by joint use of a single-frequency GPS and a MEMS accelerometer

    Science.gov (United States)

    Tu, R.; Wang, R.; Ge, M.; Walter, T. R.; Ramatschi, M.; Milkereit, C.; Bindi, D.; Dahm, T.

    2013-08-01

    detection and precise estimation of strong ground motion are crucial for rapid assessment and early warning of geohazards such as earthquakes, landslides, and volcanic activity. This challenging task can be accomplished by combining GPS and accelerometer measurements because of their complementary capabilities to resolve broadband ground motion signals. However, for implementing an operational monitoring network of such joint measurement systems, cost-effective techniques need to be developed and rigorously tested. We propose a new approach for joint processing of single-frequency GPS and MEMS (microelectromechanical systems) accelerometer data in real time. To demonstrate the performance of our method, we describe results from outdoor experiments under controlled conditions. For validation, we analyzed dual-frequency GPS data and images recorded by a video camera. The results of the different sensors agree very well, suggesting that real-time broadband information of ground motion can be provided by using single-frequency GPS and MEMS accelerometers.

  7. Monitoring volcanic threats using ASTER satellite data

    Science.gov (United States)

    Duda, K.A.; Wessels, R.; Ramsey, M.; Dehn, J.

    2008-01-01

    This document summarizes ongoing activities associated with a research project funded by the National Aeronautics and Space Administration (NASA) focusing on volcanic change detection through the use of satellite imagery. This work includes systems development as well as improvements in data analysis methods. Participating organizations include the NASA Land Processes Distributed Active Archive Center (LP DAAC) at the U.S. Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS), the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Science Team, the Alaska Volcano Observatory (AVO) at the USGS Alaska Science Center, the Jet Propulsion Laboratory/California Institute of Technology (JPL/CalTech), the University of Pittsburgh, and the University of Alaska Fairbanks. ?? 2007 IEEE.

  8. High-resolution remote sensing data to monitor active volcanic areas: an application to the 2011-2015 eruptive activity of Mount Etna (Italy) (Conference Presentation)

    Science.gov (United States)

    Marsella, Maria

    2016-10-01

    In volcanic areas, where it could be difficult to gain access to the most critical zones for carrying out direct surveys, remote sensing proved to have remarkable potentialities to follow the evolution of lava flow, as well as to detect slope instability processes induced by volcanic activity. By exploiting SAR and optical data a methodology for observing and quantifying eruptive processes was developed. The approach integrates HR optical images and SAR interferometric products and can optimize the observational capability of standard surveillance activities based on in-situ video camera network. A dedicated tool for mapping the evolution of the lava field, using both ground-based and satellite data, was developed and tested to map lava flows during the 2011-2015 eruptive activities. Ground based data were collected using the permanent ground NEtwork of Thermal and VIsible Sensors located on Mt. Etna (Etna_NETVIS) and allowed to downscale the information derived from satellite data and to integrate the satellite datasets in case of incomplete coverage or missing acquisitions. This work was developed in the framework of the EU-FP7 project "MED-SUV" (MEDiterranean SUpersite Volcanoes).

  9. Use of Low-Cost Acquisition Systems with an Embedded Linux Device for Volcanic Monitoring.

    Science.gov (United States)

    Moure, David; Torres, Pedro; Casas, Benito; Toma, Daniel; Blanco, María José; Del Río, Joaquín; Manuel, Antoni

    2015-08-19

    This paper describes the development of a low-cost multiparameter acquisition system for volcanic monitoring that is applicable to gravimetry and geodesy, as well as to the visual monitoring of volcanic activity. The acquisition system was developed using a System on a Chip (SoC) Broadcom BCM2835 Linux operating system (based on DebianTM) that allows for the construction of a complete monitoring system offering multiple possibilities for storage, data-processing, configuration, and the real-time monitoring of volcanic activity. This multiparametric acquisition system was developed with a software environment, as well as with different hardware modules designed for each parameter to be monitored. The device presented here has been used and validated under different scenarios for monitoring ocean tides, ground deformation, and gravity, as well as for monitoring with images the island of Tenerife and ground deformation on the island of El Hierro.

  10. Use of Low-Cost Acquisition Systems with an Embedded Linux Device for Volcanic Monitoring

    Directory of Open Access Journals (Sweden)

    David Moure

    2015-08-01

    Full Text Available This paper describes the development of a low-cost multiparameter acquisition system for volcanic monitoring that is applicable to gravimetry and geodesy, as well as to the visual monitoring of volcanic activity. The acquisition system was developed using a System on a Chip (SoC Broadcom BCM2835 Linux operating system (based on DebianTM that allows for the construction of a complete monitoring system offering multiple possibilities for storage, data-processing, configuration, and the real-time monitoring of volcanic activity. This multiparametric acquisition system was developed with a software environment, as well as with different hardware modules designed for each parameter to be monitored. The device presented here has been used and validated under different scenarios for monitoring ocean tides, ground deformation, and gravity, as well as for monitoring with images the island of Tenerife and ground deformation on the island of El Hierro.

  11. The Online GVP/USGS Weekly Volcanic Activity Report: Providing Timely Information About Worldwide Volcanism

    Science.gov (United States)

    Mayberry, G. C.; Guffanti, M. C.; Luhr, J. F.; Venzke, E. A.; Wunderman, R. L.

    2001-12-01

    The awesome power and intricate inner workings of volcanoes have made them a popular subject with scientists and the general public alike. About 1500 known volcanoes have been active on Earth during the Holocene, approximately 50 of which erupt per year. With so much activity occurring around the world, often in remote locations, it can be difficult to find up-to-date information about current volcanism from a reliable source. To satisfy the desire for timely volcano-related information the Smithsonian Institution and US Geological Survey combined their strengths to create the Weekly Volcanic Activity Report. The Smithsonian's Global Volcanism Program (GVP) has developed a network of correspondents while reporting worldwide volcanism for over 30 years in their monthly Bulletin of the Global Volcanism Network. The US Geological Survey's Volcano Hazards Program studies and monitors volcanoes in the United States and responds (upon invitation) to selected volcanic crises in other countries. The Weekly Volcanic Activity Report is one of the most popular sites on both organization's websites. The core of the Weekly Volcanic Activity Report is the brief summaries of current volcanic activity around the world. In addition to discussing various types of volcanism, the summaries also describe precursory activity (e.g. volcanic seismicity, deformation, and gas emissions), secondary activity (e.g. debris flows, mass wasting, and rockfalls), volcanic ash hazards to aviation, and preventative measures. The summaries are supplemented by links to definitions of technical terms found in the USGS photoglossary of volcano terms, links to information sources, and background information about reported volcanoes. The site also includes maps that highlight the location of reported volcanoes, an archive of weekly reports sorted by volcano and date, and links to commonly used acronyms. Since the Weekly Volcanic Activity Report's inception in November 2000, activity has been reported at

  12. Volcanic eruptions and solar activity

    Science.gov (United States)

    Stothers, Richard B.

    1989-01-01

    The historical record of large volcanic eruptions from 1500 to 1980 is subjected to detailed time series analysis. In two weak but probably statistically significant periodicities of about 11 and 80 yr, the frequency of volcanic eruptions increases (decreases) slightly around the times of solar minimum (maximum). Time series analysis of the volcanogenic acidities in a deep ice core from Greenland reveals several very long periods ranging from about 80 to about 350 yr which are similar to the very slow solar cycles previously detected in auroral and C-14 records. Solar flares may cause changes in atmospheric circulation patterns that abruptly alter the earth's spin. The resulting jolt probably triggers small earthquakes which affect volcanism.

  13. Monitoring gas emissions can help forecast volcanic eruptions

    Science.gov (United States)

    Kern, Christoph; Maarten de Moor,; Bo Galle,

    2015-01-01

    As magma ascends in active volcanoes, dissolved volatiles partition from melt into a gas phase, rise, and are released into the atmosphere from volcanic vents. The major components of high-temperature volcanic gas are typically water vapor, carbon dioxide, and sulfur dioxide. 

  14. Monitoring glaciers and indications of subglacial volcanic activity using small-scale Top-Hat reflectors - An IsViews experiment on Myrdalsjökull, Iceland

    Science.gov (United States)

    Minet, Christian; Duque Biarge, Sergi; Jaenicke, Julia; Münzer, Ulrich; Mayer, Christoph; Franke, Jonas; Guðmundsson, Águst; Parizzi, Alessandro; Fritz, Thomas; Eineder, Michael

    2014-05-01

    Subglacial volcanic eruptions often provide indications of activity some time before the actual catastrophic event. Surface undulations appear on top of the ice cap and meltwater torrents can occur at the glacier margin. Even large scale uplifts of ice caps have been observed. Within the project IsViews a processing chain, based on high spatially and temporally resolved remote sensing imagery, will be developed in order to automatically identify such early indications. The main data used for this analysis are acquired by the TerraSAR-X, TanDEM-X and RapidEye satellites. First investigations concerning the feasibility of the near real-time warning system and the general baseline conditions are carried out on two large plateau glaciers in southern Iceland, namely Mördalsjökull and Vatnajökull. Within the 2013 IsViews field work an experiment was started in order to test a new way of glacier monitoring. Two test sites were established on the Mördalsjökull ice cap (one at the equilibrium line and one below), each consisting of a permanent GPS station and two nearby RADAR reflectors. These RADAR reflectors are specially designed Top-Hat reflectors, which are cheap to manufacture, small (50 cm diameter) and lightweight and therefore easy to handle, transport and deploy. Their special design makes them visible in SAR images independent of orientation, so different acquisition geometries and even different sensors can be used. The drawback of the small, low reflecting Top-Hat can be overcome by using the newly implemented Staring Spotlight Mode of the German SAR Satellite TerraSAR-X, providing an unprecedented resolution of down to 20 cm in the azimuth direction. The reflectors, as point targets, allow absolute positioning within the cm-level in the TerraSAR-X data. Time series of SAR data can be used to derive position and altitude changes of the reflector itself and possibly even melting rates by exploiting the different signal paths. The visibility of the Top

  15. A Proposed Community Network For Monitoring Volcanic Emissions In Saint Lucia, Lesser Antilles

    Science.gov (United States)

    Joseph, E. P.; Beckles, D. M.; Robertson, R. E.; Latchman, J. L.; Edwards, S.

    2013-12-01

    Systematic geochemical monitoring of volcanic systems in the English-speaking islands of the Lesser Antilles was initiated by the UWI Seismic Research Centre (SRC) in 2000, as part of its volcanic surveillance programme for the English-speaking islands of the Lesser Antilles. This programme provided the first time-series observations used for the purpose of volcano monitoring in Dominica and Saint Lucia, permitted the characterization of the geothermal fluids associated with them, and established baseline studies for understanding of the hydrothermal systems during periods of quiescence (Joseph et al., 2011; Joseph et al., 2013). As part of efforts to improve and expand the capacity of SRC to provide volcanic surveillance through its geothermal monitoring programme, it is necessary to develop economically sustainable options for the monitoring of volcanic emissions/pollutants. Towards this effort we intend to work in collaboration with local authorities in Saint Lucia, to develop a monitoring network for quantifying the background exposure levels of ambient concentrations of volcanic pollutants, SO2 in air and As in waters (as health significant marker elements in the geothermal emissions) that would serve as a model for the emissions monitoring network for other volcanic islands. This programme would facilitate the building of local capacity and training to monitor the hazardous exposure, through the application and transfer of a regionally available low-cost and low-technology SO2 measurement/detection system in Saint Lucia. Existing monitoring technologies to inform evidence based health practices are too costly for small island Caribbean states, and no government policies or health services measures currently exist to address/mitigate these influences. Gases, aerosols and toxic elements from eruptive and non-eruptive volcanic activity are known to adversely affect human health and the environment (Baxter, 2000; Zhang et al., 2008). Investigations into the

  16. Monitoring volcanic systems through cross-correlation of coincident A-Train satellite data.

    Science.gov (United States)

    Flower, V. J. B.; Carn, S. A.; Wright, R.

    2014-12-01

    The remote location and inaccessibility of many active volcanic systems around the world hinders detailed investigation of their eruptive dynamics. One methodology for monitoring such locations is through the utilisation of multiple satellite datasets to elucidate underlying eruption dynamics and aid volcanic hazard mitigation. Whilst satellite datasets are often analysed individually, here we exploit the multi-platform NASA A-Train satellite constellation, including the Ozone Monitoring Instrument (OMI) on Aura and Moderate Resolution Imaging Spectroradiometer (MODIS) on Aqua. OMI measures volcanic emissions (e.g. sulphur dioxide, ash) whilst MODIS enables monitoring of thermal anomalies (e.g. lava flows, lava lakes, pyroclastic deposits), allowing analysis of a more diverse range of volcanic unrest than is possible using a single measurement technique alone, and permitting cross-correlation between datasets for specific locations to assess cyclic activity. A Multi-taper (MTM) Fast Fourier Transform (FFT) analysis was implemented at an initial sample site (Soufriere Hills volcano [SHV], Montserrat) facilitating cycle identification and subsequent comparison with existing ground-based data. Corresponding cycles at intervals of 8, 12 and ~50 days were identified in both the satellite-based SO2 and thermal infrared signals and ground-based SO2 measurements (Nicholson et al. 2013), validating the methodology. Our analysis confirms the potential for identification of cyclical volcanic activity through synergistic analysis of satellite data, which would be of particular value at poorly monitored volcanic systems. Following our initial test at SHV, further sample sites have been selected in locations with varied eruption dynamics and monitoring capabilities including Ambrym (Vanuatu), Kilauea (Hawaii), Nyiragongo (DR Congo) and Etna (Italy) with the intention of identifying not only cyclic signals that can be attributed to volcanic systems but also those which are

  17. Volcanic activity: a review for health professionals.

    Science.gov (United States)

    Newhall, C G; Fruchter, J S

    1986-03-01

    Volcanoes erupt magma (molten rock containing variable amounts of solid crystals, dissolved volatiles, and gas bubbles) along with pulverized pre-existing rock (ripped from the walls of the vent and conduit). The resulting volcanic rocks vary in their physical and chemical characteristics, e.g., degree of fragmentation, sizes and shapes of fragments, minerals present, ratio of crystals to glass, and major and trace elements composition. Variability in the properties of magma, and in the relative roles of magmatic volatiles and groundwater in driving an eruption, determine to a great extent the type of an eruption; variability in the type of an eruption in turn influences the physical characteristics and distribution of the eruption products. The principal volcanic hazards are: ash and larger fragments that rain down from an explosion cloud (airfall tephra and ballistic fragments); flows of hot ash, blocks, and gases down the slopes of a volcano (pyroclastic flows); "mudflows" (debris flows); lava flows; and concentrations of volcanic gases in topographic depressions. Progress in volcanology is bringing improved long- and short-range forecasts of volcanic activity, and thus more options for mitigation of hazards. Collaboration between health professionals and volcanologists helps to mitigate health hazards of volcanic activity.

  18. Volcanic Monitoring Techniques Applied to Controlled Fragmentation Experiments

    Science.gov (United States)

    Kueppers, U.; Alatorre-Ibarguengoitia, M. A.; Hort, M. K.; Kremers, S.; Meier, K.; Scharff, L.; Scheu, B.; Taddeucci, J.; Dingwell, D. B.

    2010-12-01

    Volcanic eruptions are an inevitable natural threat. The range of eruptive styles is large and short term fluctuations of explosivity or vent position pose a large risk that is not necessarily confined to the immediate vicinity of a volcano. Explosive eruptions rather may also affect aviation, infrastructure and climate, regionally as well as globally. Multiparameter monitoring networks are deployed on many active volcanoes to record signs of magmatic processes and help elucidate the secrets of volcanic phenomena. However, our mechanistic understanding of many processes hiding in recorded signals is still poor. As a direct consequence, a solid interpretation of the state of a volcano is still a challenge. In an attempt to bridge this gap, we combined volcanic monitoring and experimental volcanology. We performed 15 well-monitored, field-based, experiments and fragmented natural rock samples from Colima volcano (Mexico) by rapid decompression. We used cylindrical samples of 60 mm height and 25 mm and 60 mm diameter, respectively, and 25 and 35 vol.% open porosity. The applied pressure range was from 4 to 18 MPa. Using different experimental set-ups, the pressurised volume above the samples ranged from 60 - 170 cm3. The experiments were performed at ambient conditions and at controlled sample porosity and size, confinement geometry, and applied pressure. The experiments have been thoroughly monitored with 1) Doppler Radar (DR), 2) high-speed and high-definition cameras, 3) acoustic and infrasound sensors, 4) pressure transducers, and 5) electrically conducting wires. Our aim was to check for common results achieved by the different approaches and, if so, calibrate state-of-the-art monitoring tools. We present how the velocity of the ejected pyroclasts was measured by and evaluated for the different approaches and how it was affected by the experimental conditions and sample characteristics. We show that all deployed instruments successfully measured the pyroclast

  19. Google Mapplets for Earthquakes and Volcanic Activity

    Science.gov (United States)

    Haefner, S. A.; Venezky, D. Y.

    2007-12-01

    The USGS Earthquake and Volcano Hazards Programs monitor, assess, and issue warnings of natural hazards. Users can access our hazards information through our web pages, RSS feeds, and now through USGS Mapplets. Mapplets allow third party data layers to be added on top of Google Maps (http://maps.google.com - My Maps tab). Mapplets are created by parsing a GeoRSS feed, which involves searching through an XML file for location data and plotting the associated information on a map. The new Mapplets allow users to view both real-time earthquakes and current volcanic activity on the same map for the first time. In addition, the USGS Mapplets have been added to Google's extensive collection of Mapplets, allowing users to add the types of information they want to see on their own customized maps. The Earthquake Mapplet plots the past week of earthquakes around the world, showing the location, time and magnitude. The Volcano Mapplet displays the latest U.S. volcano updates, including the current level of both ground-based and aviation hazards. Join us to discuss how Mapplets are made and how they can be used to create your own customized map.

  20. Tellurium in active volcanic environments: Preliminary results

    Science.gov (United States)

    Milazzo, Silvia; Calabrese, Sergio; D'Alessandro, Walter; Brusca, Lorenzo; Bellomo, Sergio; Parello, Francesco

    2014-05-01

    Tellurium is a toxic metalloid and, according to the Goldschmidt classification, a chalcophile element. In the last years its commercial importance has considerably increased because of its wide use in solar cells, thermoelectric and electronic devices of the last generation. Despite such large use, scientific knowledge about volcanogenic tellurium is very poor. Few previous authors report result of tellurium concentrations in volcanic plume, among with other trace metals. They recognize this element as volatile, concluding that volcanic gases and sulfur deposits are usually enriched with tellurium. Here, we present some results on tellurium concentrations in volcanic emissions (plume, fumaroles, ash leachates) and in environmental matrices (soils and plants) affected by volcanic emissions and/or deposition. Samples were collected at Etna and Vulcano (Italy), Turrialba (Costa Rica), Miyakejima, Aso, Asama (Japan), Mutnovsky (Kamchatka) at the crater rims by using common filtration techniques for aerosols (polytetrafluoroethylene filters). Filters were both eluted with Millipore water and acid microwave digested, and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Volcanic ashes emitted during explosive events on Etna and Copahue (Argentina) were analyzed for tellurium bulk composition and after leaching experiments to evaluate the soluble fraction of tellurium. Soils and leaves of vegetation were also sampled close to active volcanic vents (Etna, Vulcano, Nisyros, Nyiragongo, Turrialba, Gorely and Masaya) and investigated for tellurium contents. Preliminary results showed very high enrichments of tellurium in volcanic emissions comparing with other volatile elements like mercury, arsenic, thallium and bismuth. This suggests a primary transport in the volatile phase, probably in gaseous form (as also suggested by recent studies) and/or as soluble salts (halides and/or sulfates) adsorbed on the surface of particulate particles and ashes. First

  1. Seismic monitoring at Cascade Volcanic Centers, 2004?status and recommendations

    Science.gov (United States)

    Moran, Seth C.

    2004-01-01

    The purpose of this report is to assess the current (May, 2004) status of seismic monitoring networks at the 13 major Cascade volcanic centers. Included in this assessment are descriptions of each network, analyses of the ability of each network to detect and to locate seismic activity, identification of specific weaknesses in each network, and a prioritized list of those networks that are most in need of additional seismic stations. At the outset it should be recognized that no Cascade volcanic center currently has an adequate seismic network relative to modern-day networks at Usu Volcano (Japan) or Etna and Stromboli volcanoes (Italy). For a system the size of Three Sisters, for example, a modern-day, cutting-edge seismic network would ideally consist of a minimum of 10 to 12 short-period three-component seismometers (for determining particle motions, reliable S-wave picks, moment tensor inversions, fault-plane solutions, and other important seismic parameters) and 7 to 10 broadband sensors (which, amongst other considerations, enable detection and location of very long period (VLP) and other low-frequency events, moment tensor inversions, and, because of their wide dynamic range, on-scale recording of large-amplitude events). Such a dense, multi component seismic network would give the ability to, for example, detect in near-real-time earthquake migrations over a distance of ~0.5km or less, locate tremor sources, determine the nature of a seismic source (that is, pure shear, implosive, explosive), provide on-scale recordings of very small and very large-amplitude seismic signals, and detect localized changes in seismic stress tensor orientations caused by movement of magma bodies. However, given that programmatic resources are currently limited, installation of such networks at this time is unrealistic. Instead, this report focuses on identifying what additional stations are needed to guarantee that anomalous seismicity associated with volcanic unrest will be

  2. Impact of Volcanic Activity on AMC Channel Operations

    Science.gov (United States)

    2014-06-13

    IMPACT OF VOLCANIC ACTIVITY ON AMC CHANNEL OPERATIONS GRADUATE RESEARCH PROJECT Matthew D... VOLCANIC ACTIVITY ON AMC CHANNEL OPERATIONS GRADUATE RESEARCH PROJECT Presented to the Faculty Department of Operational Sciences...AFIT-ENS-GRP-14-J-11 IMPACT OF VOLCANIC ACTIVITY ON AMC CHANNEL OPERATIONS Matthew D. Meshanko, BS, MA Major, USAF

  3. Remote monitoring of volcanic gases using passive Fourier transform spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Love, S.P.; Goff, F.; Counce, D.; Schmidt, S.C. [Los Alamos National Lab., NM (United States); Siebe, C.; Delgado, H. [Univ. Nactional Autonoma de Mexico, Coyoacan (Mexico)

    1999-06-01

    Volcanic gases provide important insights on the internal workings of volcanoes and changes in their composition and total flux can warn of impending changes in a volcano`s eruptive state. In addition, volcanoes are important contributors to the earth`s atmosphere, and understanding this volcanic contribution is crucial for unraveling the effect of anthropogenic gases on the global climate. Studies of volcanic gases have long relied upon direct in situ sampling, which requires volcanologists to work on-site within a volcanic crater. In recent years, spectroscopic techniques have increasingly been employed to obtain information on volcanic gases from greater distances and thus at reduced risk. These techniques have included UV correlation spectroscopy (Cospec) for SO{sub 2} monitoring, the most widely-used technique, and infrared spectroscopy in a variety of configurations, both open- and closed-path. Francis et al. have demonstrated good results using the sun as the IR source. This solar occultation technique is quite useful, but puts rather strong restrictions on the location of instrument and is thus best suited to more accessible volcanoes. In order to maximize the flexibility and range of FTIR measurements at volcanoes, work over the last few years has emphasized techniques which utilize the strong radiance contrast between the volcanic gas plume and the sky. The authors have successfully employed these techniques at several volcanoes, including the White Island and Ruapehu volcanoes in New Zealand, the Kilauea volcano on Hawaii, and Mt. Etna in Italy. But Popocatepetl (5452 m), the recently re-awakened volcano 70 km southeast of downtown Mexico City, has provided perhaps the best examples to date of the usefulness of these techniques.

  4. Multidimensional analysis and probabilistic model of volcanic and seismic activities

    Science.gov (United States)

    Fedorov, V.

    2009-04-01

    .I. Gushchenko, 1979) and seismological (database of USGS/NEIC Significant Worldwide Earthquakes, 2150 B.C.- 1994 A.D.) information which displays dynamics of endogenic relief-forming processes over a period of 1900 to 1994. In the course of the analysis, a substitution of calendar variable by a corresponding astronomical one has been performed and the epoch superposition method was applied. In essence, the method consists in that the massifs of information on volcanic eruptions (over a period of 1900 to 1977) and seismic events (1900-1994) are differentiated with respect to value of astronomical parameters which correspond to the calendar dates of the known eruptions and earthquakes, regardless of the calendar year. The obtained spectra of volcanic eruptions and violent earthquake distribution in the fields of the Earth orbital movement parameters were used as a basis for calculation of frequency spectra and diurnal probability of volcanic and seismic activity. The objective of the proposed investigations is a probabilistic model development of the volcanic and seismic events, as well as GIS designing for monitoring and forecast of volcanic and seismic activities. In accordance with the stated objective, three probability parameters have been found in the course of preliminary studies; they form the basis for GIS-monitoring and forecast development. 1. A multidimensional analysis of volcanic eruption and earthquakes (of magnitude 7) have been performed in terms of the Earth orbital movement. Probability characteristics of volcanism and seismicity have been defined for the Earth as a whole. Time intervals have been identified with a diurnal probability twice as great as the mean value. Diurnal probability of volcanic and seismic events has been calculated up to 2020. 2. A regularity is found in duration of dormant (repose) periods has been established. A relationship has been found between the distribution of the repose period probability density and duration of the period. 3

  5. Real-time satellite monitoring of volcanic hot spots

    Science.gov (United States)

    Harris, Andrew J. L.; Flynn, Luke P.; Dean, Ken; Pilger, Eric; Wooster, Martin; Okubo, Chris; Mouginis-Mark, Peter; Garbeil, Harold; Thornber, Carl; De la Cruz-Reyna, Servando; Rothery, Dave; Wright, Robert

    Direct satellite data reception at high temporal frequencies and automated processing enable near-real-time, near-continuous thermal monitoring of volcanoes. We review what has been achieved in terms of turning this capability into real-time tools of use to volcano monitoring agencies. Current capabilities focus on 2 instruments: the advanced very high resolution radiometer (AVHRR) and the Geostationary Operational Environmental Satellite (GOES) imager. Collection of lO AVHRR images per day covering Alaska, the Aleutians, and Kamchatka allows routine, on-reception analysis of volcanic hot spots across this region. Data collected between 1996 and 1998 detected 302 hot spots due to lava flows, lava domes, pyroclastic flows, fumaroles, and geothermally heated lakes at 12 different volcanoes. Information was used for hazard mitigation by the Alaskan Volcano Observatory. GOES provides data for North and South American volcanoes every 15-30 minutes. Automated processing allows eruption information and alerts to be posted on the Internet within 15-60 minutes of reception. We use June 1998 to demonstrate the frequency of data acquisition. During this month 2879 GOES images were collected from which 14,832 sub-images of 6 active volcanoes were processed. Although 82% (12,200) of these sub-images were cloud covered, hot spots were still evident on 11% (1634) of the sub-images. Analysis of GOES data for 1998 identified hot spots due to (1) lava flows at Kilauea and Cerro Azul, (2) dome extrusion and explosive activity at Lascar, Popocatepetl, Colima and Pacaya, and (3) dome cooling and collapse at Soufriere Hills. We were also able to suggest that reports of lava flow activity at Cerro Negro were false. This information was supplied to, and used by, various agencies whose task it is to monitor these volcanoes. Global thermal monitoring will become a reality with the launch of the Earth Observing System's moderate resolution imaging spectrometer (MODIS). An automated thermal

  6. Monitoring Persistent Volcanic Emissions from Sulphur Springs, Saint Lucia: A Community Approach to Disaster Risk Reduction

    Science.gov (United States)

    Joseph, E. P.; Beckles, D. M.; Cox, L.; Jackson, V. B.; Alexander, D.

    2014-12-01

    Volcanic and geothermal emissions are known natural sources of volatiles to the atmosphere. Volcanogenic air pollutants known to cause the most serious impact are carbon dioxide (CO2), sulphur dioxide (SO2), hydrogen chloride (HCl) and hydrogen fluoride (HF). Some studies into the potential for volcanic emissions to produce chronic diseases in humans indicate that areas of major concern include respiratory problems, particularly silicosis (Allen et al. 2000; Baxter et al. 1999; Buist et al. 1986), psychological stress (Shore et al. 1986), and chemical impacts of gas or ash (Giammanco et al. 1998). Sulphur Springs Park in Saint Lucia has a very high recreational value with >200,000 visitors annually, while the nearby town of Soufrière has >8,400 residents. Residents and visitors have raised concerns about the volcanic emissions and its health effects. As part of the volcanic surveillance programme undertaken by the UWI, Seismic Research Centre (SRC) in Saint Lucia, a new monitoring network has been established for quantifying the ambient SO2 in air, to which staff and visitors at the volcanic park are exposed to. The implementation and continued operation of this network has involved the training of local personnel in the active field sampling and analytical techniques required for the assessment of ambient SO2 concentrations, using a low cost monitor as well as commercial passive samplers. This approach recognizes that environmental hazards are a usual part of life and productive livelihoods, and to minimize post-disaster response and recovery it is beneficial to promote preparedness and mitigation, which is best achieved at the local level with community involvement. It is also intended that the volcanic emissions monitoring network could be used as a method to establish and maintain community-based initiatives that would also be helpful when volcanic threat manifests.

  7. Active Volcanism on Io as Seen by Galileo SSI

    Science.gov (United States)

    McEwen, A.S.; Keszthelyi, L.; Geissler, P.; Simonelli, D.P.; Carr, M.H.; Johnson, T.V.; Klaasen, K.P.; Breneman, H.H.; Jones, T.J.; Kaufman, J.M.; Magee, K.P.; Senske, D.A.; Belton, M.J.S.; Schubert, G.

    1998-01-01

    Active volcanism on Io has been monitored during the nominal Galileo satellite tour from mid 1996 through late 1997. The Solid State Imaging (SSI) experiment was able to observe many manifestations of this active volcanism, including (1) changes in the color and albedo of the surface, (2) active airborne plumes, and (3) glowing vents seen in eclipse. About 30 large-scale (tens of kilometers) surface changes are obvious from comparison of the SSI images to those acquired by Voyager in 1979. These include new pyroclastic deposits of several colors, bright and dark flows, and caldera-floor materials. There have also been significant surface changes on Io during the Galileo mission itself, such as a new 400-km-diameter dark pyroclastic deposit around Pillan Patera. While these surface changes are impressive, the number of large-scale changes observed in the four months between the Voyager 1 and Voyager 2 flybys in 1979 suggested that over 17 years the cumulative changes would have been much more impressive. There are two reasons why this was not actually the case. First, it appears that the most widespread plume deposits are ephemeral and seem to disappear within a few years. Second, it appears that a large fraction of the volcanic activity is confined to repeated resurfacing of dark calderas and flow fields that cover only a few percent of Io's surface. The plume monitoring has revealed 10 active plumes, comparable to the 9 plumes observed by Voyager. One of these plumes was visible only in the first orbit and three became active in the later orbits. Only the Prometheus plume has been consistently active and easy to detect. Observations of the Pele plume have been particularly intriguing since it was detected only once by SSI, despite repeated attempts, but has been detected several times by the Hubble Space Telescope at 255 nm. Pele's plume is much taller (460 km) than during Voyager 1 (300 km) and much fainter at visible wavelengths. Prometheus-type plumes (50

  8. Monitoring of volcanic SO2 emissions using the GOME-2 instrument

    Science.gov (United States)

    Hedelt, Pascal; Valks, Pieter; Loyola, Diego

    2014-05-01

    This contribution focusses on the GOME-2 SO2 column products from the METOP-A and B satellites. The GOME-2 SO2 column product has been developed in the framework of EUMETSAT's Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M-SAF). Satellite-based remote sensing measurements of volcanic SO2 provide critical information for reducing volcanic hazards. Volcanic eruptions may bring ash and gases (e.g. SO2) high up into the atmosphere, where a long-range transport can occur. SO2 is an important indicator for volcanic activity and an excellent tracer for volcanic eruption clouds, especially if ash detection techniques fail. SO2 can affect aviation safety: In the cabin it can cause disease and respiratory symptoms, whereas in its hydrogenated form H2SO4 it is highly corrosive and can cause damage to jet engines as well as pitting of windscreens. We will present results for volcanic events retrieved from GOME-2 solar backscattered measurements in the UV wavelength region around 320nm using the Differential Optical Absorption Spectroscopy (DOAS) method. SO2 columns are generated operationally by DLR with the GOME Data Processor (GDP) version 4.7 and are available in near-real-time, i.e. within two hours after sensing. Using data from both MetOp satellites allows for a daily global coverage. We will furthermore present current improvements to the GOME-2 SO2 column product.

  9. Evidence of persistent seismo-volcanic activity at Marsili seamount

    Directory of Open Access Journals (Sweden)

    Antonino D'Alessandro

    2012-06-01

    Full Text Available The Marsili submarine volcano is the largest European volcano, and it can be considered as the key to our understanding of the dynamics of the spreading and back-arc lithosphere formation in the Tyrrhenian sector [Marani et al. 2004, and references therein]. Despite its size, it is very difficult to monitor due to its geographical position [D'Alessandro et al. 2011], and it still remains little known. In 2006, the Centro Nazionale Terremoti (National Earthquake Centre of the Istituto Nazionale di Geofisica e Vulcanologia (INGV deployed a broadband ocean-bottom seismometer with hydrophone (OBS/H [Mangano et al. 2011] on the flat top of Marsili volcano, at a depth of ca. 790 m. In only nine days, the instrument recorded ca. 800 seismo-volcanic events [D'Alessandro et al. 2009]. This revealed the intense seismo-volcanic activity of Marsili volcano for the first time. […] 

  10. Monitoring El Hierro submarine volcanic eruption events with a submarine seismic array

    Science.gov (United States)

    Jurado, Maria Jose; Molino, Erik; Lopez, Carmen

    2013-04-01

    A submarine volcanic eruption took place near the southernmost emerged land of the El Hierro Island (Canary Islands, Spain), from October 2011 to February 2012. The Instituto Geografico Nacional (IGN) seismic stations network evidenced seismic unrest since July 2012 and was a reference also to follow the evolution of the seismic activity associated with the volcanic eruption. From the beginning of the eruption a geophone string was installed less than 2 km away from the new volcano, next to La Restinga village shore, to record seismic activity related to the volcanic activity, continuously and with special interest on high frequency events. The seismic array was endowed with 8, high frequency, 3 component, 250 Hz, geophone cable string with a separation of 6 m between them. The analysis of the dataset using spectral techniques allows the characterization of the different phases of the eruption and the study of its dynamics. The correlation of the data analysis results with the observed sea surface activity (ash and lava emission and degassing) and also with the seismic activity recorded by the IGN field seismic monitoring system, allows the identification of different stages suggesting the existence of different signal sources during the volcanic eruption and also the posteruptive record of the degassing activity. The study shows that the high frequency capability of the geophone array allow the study of important features that cannot be registered by the standard seismic stations. The accumulative spectral amplitude show features related to eruptive changes.

  11. Volcanic Environments Monitoring by Drones Mud Volcano Case Study

    Science.gov (United States)

    Amici, S.; Turci, M.; Giulietti, F.; Giammanco, S.; Buongiorno, M. F.; La Spina, A.; Spampinato, L.

    2013-08-01

    Volcanic activity has often affected human life both at large and at small scale. For example, the 2010 Eyjafjallajokull eruption caused severe economic damage at continental scale due to its strong effect on air traffic. At a local scale, ash fall and lava flow emission can cause harm and disruption. Understanding precursory signals to volcanic eruptions is still an open and tricky challenge: seismic tremor and gas emissions, for example, are related to upcoming eruptive activity but the mechanisms are not yet completely understood. Furthermore, information related to gases emission mostly comes from the summit crater area of a volcano, which is usually hard to investigate with required accuracy. Although many regulation problems are still on the discussion table, an increasing interest in the application of cutting-edge technology like unmanned flying systems is growing up. In this sense, INGV (Istituto Nazionale di Geofisica e Vulcanologia) started to investigate the possibility to use unmanned air vehicles for volcanic environment application already in 2004. A flight both in visual- and radio-controlled mode was carried out on Stromboli volcano as feasibility test. In this work we present the preliminary results of a test performed by INGV in collaboration with the University of Bologna (aerospace division) by using a multi-rotor aircraft in a hexacopter configuration. Thermal camera observations and flying tests have been realised over a mud volcano located on its SW flank of Mt. Etna and whose activity proved to be related to early stages of magma accumulation within the volcano.

  12. Investigating volcanic hazard in Cape Verde Islands through geophysical monitoring: network description and first results

    Science.gov (United States)

    Faria, B.; Fonseca, J. F. B. D.

    2014-02-01

    We describe a new geophysical network deployed in the Cape Verde Archipelago for the assessment and monitoring of volcanic hazards as well as the first results from the network. Across the archipelago, the ages of volcanic activity range from ca. 20 Ma to present. In general, older islands are in the east and younger ones are in the west, but there is no clear age progression of eruptive activity as widely separated islands have erupted contemporaneously on geological timescales. The overall magmatic rate is low, and there are indications that eruptive activity is episodic, with intervals between episodes of intense activity ranging from 1 to 4 Ma. Although only Fogo Island has experienced eruptions (mainly effusive) in the historic period (last 550 yr), Brava and Santo Antão have experienced numerous geologically recent eruptions, including violent explosive eruptions, and show felt seismic activity and geothermal activity. Evidence for recent volcanism in the other islands is more limited and the emphasis has therefore been on monitoring of the three critical islands of Fogo, Brava and Santo Antão, where volcanic hazard levels are highest. Geophysical monitoring of all three islands is now in operation. The first results show that on Fogo, the seismic activity is dominated by hydrothermal events and volcano-tectonic events that may be related to settling of the edifice after the 1995 eruption; in Brava by volcano-tectonic events (mostly offshore), and in Santo Antão by volcano-tectonic events, medium-frequency events and harmonic tremor. Both in Brava and in Santo Antão, the recorded seismicity indicates that relatively shallow magmatic systems are present and causing deformation of the edifices that may include episodes of dike intrusion.

  13. Short-term spasmodic switching of volcanic tremor source activation in a conduit of the 2011 Kirishima eruption

    Science.gov (United States)

    Matsumoto, S.; Shimizu, H.; Matsushima, T.; Uehira, K.; Yamashita, Y.; Nakamoto, M.; Miyazaki, M.; Chikura, H.

    2012-04-01

    Volcanic tremors are seismic indicators providing clues for magma behavior, which is related to volcanic eruptions and activity. Detection of spatial and temporal variations of volcanic tremors is important for understanding the mechanism of volcanic eruptions. However, temporal variations of tremor activity in short-term than a minute have not been previously detected by seismological observations around volcanoes. Here, we show that volcanic tremor sources were activated at the top of the conduit (i.e. the crater) and at its lower end by analyzing seismograms from a dense seismic array during the 2011 Kirishima eruption. We observed spasmodic switching in the seismic ray direction during a volcanic tremor sequence. Such fine volcanic tremor structure suggests an interaction between tremor sources located in both deep and shallow depths. Our result suggests that seismic array observations can monitor the magma behavior and contribute to the evaluation of the activity's transition.

  14. Integrating volcanic gas monitoring with other geophysical networks in Iceland

    Science.gov (United States)

    Pfeffer, Melissa A.

    2017-04-01

    The Icelandic Meteorological Office/Icelandic Volcano Observatory is rapidly developing and improving the use of gas measurements as a tool for pre- and syn-eruptive monitoring within Iceland. Observations of deformation, seismicity, hydrological properties, and gas emissions, united within an integrated approach, can provide improved understanding of subsurface magma movements. This is critical to evaluate signals prior to and during volcanic eruptions, issue timely eruption warnings, forecast eruption behavior, and assess volcanic hazards. Gas measurements in Iceland need to be processed to account for the high degree of gas composition alteration due to interaction with external water and rocks. Deeply-sourced magmatic gases undergo reactions and modifications as they move to the surface that exercise a strong control on the composition of surface emissions. These modifications are particularly strong at ice-capped volcanoes where most surface gases are dissolved in glacial meltwater. Models are used to project backwards from surface gas measurements to what the magmatic gas composition was prior to upward migration. After the pristine magma gas composition has been determined, it is used together with fluid compositions measured in mineral hosted melt inclusions to calculate magmatic properties to understand magma storage and migration and to discern if there have been changes in the volcanic system. The properties derived from surface gas measurements can be used as input to models interpreting deformation and seismic observations, and can be used as an additional, independent observation when interpreting hydrological and seismic changes. An integrated approach aids with determining whether observed hydro/geological changes can be due to the presence of shallow magma. Constraints on parameters such as magma gas content, viscosity and compressibility can be provided by the approach described above, which can be utilized syn-eruptively to help explain

  15. Gravimetric control of active volcanic processes

    Science.gov (United States)

    Saltogianni, Vasso; Stiros, Stathis

    2017-04-01

    Volcanic activity includes phases of magma chamber inflation and deflation, produced by movement of magma and/or hydrothermal processes. Such effects usually leave their imprint as deformation of the ground surfaces which can be recorded by GNSS and other methods, on one hand, and on the other hand they can be modeled as elastic deformation processes, with deformation produced by volcanic masses of finite dimensions such as spheres, ellipsoids and parallelograms. Such volumes are modeled on the basis of inversion (non-linear, numerical solution) of systems of equations relating the unknown dimensions and location of magma sources with observations, currently mostly GNSS and INSAR data. Inversion techniques depend on the misfit between model predictions and observations, but because systems of equations are highly non-linear, and because adopted models for the geometry of magma sources is simple, non-unique solutions can be derived, constrained by local extrema. Assessment of derived magma models can be provided by independent observations and models, such as micro-seismicity distribution and changes in geophysical parameters. In the simplest case magmatic intrusions can be modeled as spheres with diameters of at least a few tens of meters at a depth of a few kilometers; hence they are expected to have a gravimetric signature in permanent recording stations on the ground surface, while larger intrusions may also have an imprint in sensors in orbit around the earth or along precisely defined air paths. Identification of such gravimetric signals and separation of the "true" signal from the measurement and ambient noise requires fine forward modeling of the wider areas based on realistic simulation of the ambient gravimetric field, and then modeling of its possible distortion because of magmatic anomalies. Such results are useful to remove ambiguities in inverse modeling of ground deformation, and also to detect magmatic anomalies offshore.

  16. Automatic semi-continuous accumulation chamber for diffuse gas emissions monitoring in volcanic and non-volcanic areas

    Science.gov (United States)

    Lelli, Matteo; Raco, Brunella; Norelli, Francesco; Virgili, Giorgio; Continanza, Davide

    2016-04-01

    Since various decades the accumulation chamber method is intensively used in monitoring activities of diffuse gas emissions in volcanic areas. Although some improvements have been performed in terms of sensitivity and reproducibility of the detectors, the equipment used for measurement of gas emissions temporal variation usually requires expensive and bulky equipment. The unit described in this work is a low cost, easy to install-and-manage instrument that will make possible the creation of low-cost monitoring networks. The Non-Dispersive Infrared detector used has a concentration range of 0-5% CO2, but the substitution with other detector (range 0-5000 ppm) is possible and very easy. Power supply unit has a 12V, 7Ah battery, which is recharged by a 35W solar panel (equipped with charge regulator). The control unit contains a custom programmed CPU and the remote transmission is assured by a GPRS modem. The chamber is activated by DataLogger unit, using a linear actuator between the closed position (sampling) and closed position (idle). A probe for the measure of soil temperature, soil electrical conductivity, soil volumetric water content, air pressure and air temperature is assembled on the device, which is already arranged for the connection of others external sensors, including an automatic weather station. The automatic station has been tested on the field at Lipari island (Sicily, Italy) during a period of three months, performing CO2 flux measurement (and also weather parameters), each 1 hour. The possibility to measure in semi-continuous mode, and at the same time, the gas fluxes from soil and many external parameters, helps the time series analysis aimed to the identification of gas flux anomalies due to variations in deep system (e.g. onset of volcanic crises) from those triggered by external conditions.

  17. Support to Aviation Control Service (SACS: an online service for near real-time satellite monitoring of volcanic plumes

    Directory of Open Access Journals (Sweden)

    H. Brenot

    2013-10-01

    Full Text Available Volcanic eruptions emit plumes of ash and gases in the atmosphere, potentially at very high altitudes. Ash rich plumes are hazardous for airplanes as ash is very abrasive and easily melts inside their engines. With more than 50 active volcanoes per year and the ever increasing number of commercial flights, the safety of airplanes is a real concern. Satellite measurements are ideal for monitoring global volcanic activity and, in combination with atmospheric dispersion models, to track and forecast volcanic plumes. Here we present the Support to Aviation Control Service (SACS, http://sacs.aeronomie.be, which is a free online service initiated by ESA for the near real-time (NRT satellite monitoring of volcanic plumes of SO2 and ash. It combines data from two UV-visible (OMI, GOME-2 and two infrared (AIRS, IASI spectrometers. This new multi-sensor warning system of volcanic plumes, running since April 2012, is based on the detection of SO2 and is optimised to avoid false alerts while at the same time limiting the number of notifications in case of large plumes. The system shows successful results with 95% of our notifications corresponding to true volcanic activity.

  18. Investigating the value of passive microwave observations for monitoring volcanic eruption source parameters

    Science.gov (United States)

    Montopoli, Mario; Cimini, Domenico; Marzano, Frank

    2016-04-01

    Volcanic eruptions inject both gas and solid particles into the Atmosphere. Solid particles are made by mineral fragments of different sizes (from few microns to meters), generally referred as tephra. Tephra from volcanic eruptions has enormous impacts on social and economical activities through the effects on the environment, climate, public health, and air traffic. The size, density and shape of a particle determine its fall velocity and thus residence time in the Atmosphere. Larger particles tend to fall quickly in the proximity of the volcano, while smaller particles may remain suspended for several days and thus may be transported by winds for thousands of km. Thus, the impact of such hazards involves local as well as large scales effects. Local effects involve mostly the large sized particles, while large scale effects are caused by the transport of the finest ejected tephra (ash) through the atmosphere. Forecasts of ash paths in the atmosphere are routinely run after eruptions using dispersion models. These models make use of meteorological and volcanic source parameters. The former are usually available as output of numerical weather prediction models or large scale reanalysis. Source parameters characterize the volcanic eruption near the vent; these are mainly the ash mass concentration along the vertical column and the top altitude of the volcanic plume, which is strictly related to the flux of the mass ejected at the emission source. These parameters should be known accurately and continuously; otherwise, strong hypothesis are usually needed, leading to large uncertainty in the dispersion forecasts. However, direct observations during an eruption are typically dangerous and impractical. Thus, satellite remote sensing is often exploited to monitor volcanic emissions, using visible (VIS) and infrared (IR) channels available on both Low Earth Orbit (LEO) and Geostationary Earth Orbit (GEO) satellites. VIS and IR satellite imagery are very useful to monitor

  19. Monitoring Volcanic Ash with MSG Seviri Image and RGB Application

    Science.gov (United States)

    Erturk, Aydin Gurol; Kerkman, Jochen

    2011-01-01

    The eruption from the Eyjafjallajökull Volcano, Iceland recently became a high importance for the Meteorological Institutes, Aviation, Satellite Centers and other related institutions. Urgent forecasts were requested by the air control centers, aviation industry and even the passengers who stuck at the airports. It was announced that thousands of flights are canceled; hundreds of thousands of passengers affected and the airlines lost around 1.7 billion dollars in April-May 2010. This is the worst aviation crises. MSG (METEOSAT Second Generation) SEVIRI (Spinning Enhanced Visible and Infrared Imagery) with its 11 narrow and 1 broad band channels have been providing a worth of data sources for nowcasting and very short forecasting. SEVIRI images and RGB applications have been acted an important role to monitor Volcanic Ash during above aviation crises. SEVIRI has an infrared channel (centered @8.7 micron) which is sensitive sand, dust and ash in the atmosphere. In this study we present Ash RGB applications derived from SEVIRI data to monitor and track Ash clouds over Europe. Two main eruptions during 14-20 April and 7-17 May 2010 will be demonstrated. In addition to this, we will propose an Ash product algorithm and discuss its weakness and strength.

  20. The Role of Volcanic Activity in Climate and Global Change

    KAUST Repository

    Stenchikov, Georgiy L.

    2015-09-23

    Explosive volcanic eruptions are magnificent events that in many ways affect the Earth\\'s natural processes and climate. They cause sporadic perturbations of the planet\\'s energy balance, activating complex climate feedbacks and providing unique opportunities to better quantify those processes. We know that explosive eruptions cause cooling in the atmosphere for a few years, but we have just recently realized that volcanic signals can be seen in the subsurface ocean for decades. The volcanic forcing of the previous two centuries offsets the ocean heat uptake and diminishes global warming by about 30%. The explosive volcanism of the twenty-first century is unlikely to either cause any significant climate signal or to delay the pace of global warming. The recent interest in dynamic, microphysical, chemical, and climate impacts of volcanic eruptions is also excited by the fact that these impacts provide a natural analogue for climate geoengineering schemes involving deliberate development of an artificial aerosol layer in the lower stratosphere to counteract global warming. In this chapter we aim to discuss these recently discovered volcanic effects and specifically pay attention to how we can learn about the hidden Earth-system mechanisms activated by explosive volcanic eruptions. To demonstrate these effects we use our own model results when possible along with available observations, as well as review closely related recent publications.

  1. Solid State Multiwavelength LIDAR for Volcanic Ash Monitoring Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Physical Sciences Inc. proposes to develop a compact, multiwavelength LIDAR with polarization analysis capability that will be able to identify volcanic ash clouds...

  2. Can satellite-based monitoring techniques be used to quantify volcanic CO2 emissions?

    Science.gov (United States)

    Schwandner, Florian M.; Carn, Simon A.; Kuze, Akihiko; Kataoka, Fumie; Shiomi, Kei; Goto, Naoki; Popp, Christoph; Ajiro, Masataka; Suto, Hiroshi; Takeda, Toru; Kanekon, Sayaka; Sealing, Christine; Flower, Verity

    2014-05-01

    Since 2010, we investigate and improve possible methods to regularly target volcanic centers from space in order to detect volcanic carbon dioxide (CO2) point source anomalies, using the Japanese Greenhouse gas Observing SATellite (GOSAT). Our long-term goals are: (a) better spatial and temporal coverage of volcano monitoring techniques; (b) improvement of the currently highly uncertain global CO2 emission inventory for volcanoes, and (c) use of volcanic CO2 emissions for high altitude, strong point source emission and dispersion studies in atmospheric science. The difficulties posed by strong relief, orogenic clouds, and aerosols are minimized by a small field of view, enhanced spectral resolving power, by employing repeat target mode observation strategies, and by comparison to continuous ground based sensor network validation data. GOSAT is a single-instrument Earth observing greenhouse gas mission aboard JAXA's IBUKI satellite in sun-synchronous polar orbit. GOSAT's Fourier-Transform Spectrometer (TANSO-FTS) has been producing total column XCO2 data since January 2009, at a repeat cycle of 3 days, offering great opportunities for temporal monitoring of point sources. GOSAT's 10 km field of view can spatially integrate entire volcanic edifices within one 'shot' in precise target mode. While it doesn't have any spatial scanning or mapping capability, it does have strong spectral resolving power and agile pointing capability to focus on several targets of interest per orbit. Sufficient uncertainty reduction is achieved through comprehensive in-flight vicarious calibration, in close collaboration between NASA and JAXA. Challenges with the on-board pointing mirror system have been compensated for employing custom observation planning strategies, including repeat sacrificial upstream reference points to control pointing mirror motion, empirical individualized target offset compensation, observation pattern simulations to minimize view angle azimuth. Since summer 2010

  3. 2009 Volcanic activity in Alaska, Kamchatka, and the Kurile Islands: summary of events and response of the Alaska Volcano Observatory

    Science.gov (United States)

    McGimsey, Robert G.; Neal, Christina A.; Girina, Olga A.; Chibisova, Marina; Rybin, Alexander

    2014-01-01

    The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, volcanic unrest, and reports of unusual activity at or near eight separate volcanic centers in Alaska during 2009. The year was highlighted by the eruption of Redoubt Volcano, one of three active volcanoes on the western side of Cook Inlet and near south-central Alaska's population and commerce centers, which comprise about 62 percent of the State's population of 710,213 (2010 census). AVO staff also participated in hazard communication and monitoring of multiple eruptions at ten volcanoes in Russia as part of its collaborative role in the Kamchatka and Sakhalin Volcanic Eruption Response Teams.

  4. 卫星遥感技术在火山灰云监测中的应用%APPLICATION OF SATELLITE REMOTE SENSING IN VOLCANIC ASH CLOUD MONITORING

    Institute of Scientific and Technical Information of China (English)

    尹京苑; 沈迪; 李成范

    2013-01-01

    A large volcanic eruption can produce large amounts of volcanic ash,water vapor and heat,and form the volcanic ash cloud.The volcanic ash cloud is mainly composed of volcanic ash debris in diameter less than 2mm and gases including SO2,H2S,CO2,the mixture of the two can form acidic aerosols which can stay in the atmosphere for a long time.It not only destructs the balance of earth's surface solar radiation and causes the depletion of the ozone layer,the greenhouse effect,air pollution,acid rain,anomalies of air temperature and precipitation,and other major global climate and environmental changes,but also damages and corrodes the structure of an aircraft,reduces the visibility and jams the radio communication system.The most serious problem is that the volcanic ash debris particles are capable of cooling and adhering to the aircraft engine blades after high-temperature melting,resulting in the flameout of aircraft engine.Under the background of globalization and the boom of air-transport industry,the volcanic ash cloud is a serious threat to aviation safety.Remote sensing technology can quickly and accurately obtain the information of the surface's and the atmosphere's changes,therefore it is playing an important role in monitoring volcanic activity.In recent years,with the advancement of sensor technology,the thermal infrared remote sensing technology has become an important means of monitoring the volcanic ash cloud.Currently,there have been a variety of remote sensors for volcanic ash cloud monitoring.Meanwhile,based on that,a series of volcanic ash cloud monitoring algorithms have also been developed for different remote sensors.However,most of the volcanic ash cloud monitoring algorithms have limitations of a low accuracy and a narrow scope.This paper tries to conduct a more comprehensive overview of the different types of remote sensors and the different algorithms for volcanic ash cloud monitoring.First,the damage of volcanic ash cloud to the natural

  5. Development of a low cost and low power consumption system for monitoring CO_{2} soil concentration in volcanic areas.

    Science.gov (United States)

    Awadallah Estévez, Shadia; Moure-García, David; Torres-González, Pedro; Acosta Sánchez, Leopoldo; Domínguez Cerdeña, Itahiza

    2017-04-01

    Volatiles dissolved in magma are released as gases when pressure or stress conditions change. H2O, CO2, SO2 and H2S are the most abundant gases involved in volcanic processes. Emission rates are related to changes in the volcanic activity. Therefore, in order to predict possible eruptive events, periodic measurements of CO2 concentrations from the soil should be carried out. In the last years, CO2 monitoring has been widespread for many reasons. A direct relationship between changes in volcanic activity and variations in concentration, diffuse flux and isotope ratios of this gas, have been observed prior to some eruptions or unrest processes. All these factors have pointed out the fact that CO2 emission data are crucial in volcanic monitoring programs. In addition, relevant instrumentation development has also taken place: improved accuracy, cost reduction and portability. Considering this, we propose a low cost and a low power consumption system for measuring CO2 concentration in the soil based on Arduino. Through a perforated pick-axe buried at a certain depth, gas samples are periodically taken with the aid of a piston. These samples are injected through a pneumatic circuit in the spectrometer, which measures the CO2 concentration. Simultaneously, the system records the following meteorological parameters: atmospheric pressure, precipitation, relative humidity and air and soil temperature. These parameters are used to correct their possible influence in the CO2 soil concentration. Data are locally stored (SD card) and transmitted via GPRS or WIFI to a data analysis center.

  6. The Extremes of Volcanic Activity: Earth and Jupiter's Moon Io

    Science.gov (United States)

    Lowes, L. L.; Lopes, R.

    2004-12-01

    Jupiter's moon Io is the solar system's most volcanically active body, and the only place that magmatic volcanic eruptions have been observed beyond Earth. One of the first images of Io obtained by NASA's Voyager 1 spacecraft in 1979 shows a plume above one of its volcanoes. The NASA Voyager and Galileo spacecraft imaged many explosive eruptions of plumes and deposits - which travel hundreds of kilometers (farther than on the Earth or the Moon). Very hot lavas that are erupting from volcanic vents on Io may be similar to lavas that erupted on Earth billions of years ago. Understanding the physical processes driving volcanic eruptions is important for the understanding of terrestrial volcanoes, not only because of their potential hazards, but also as geologic resources, biologic environments, and for their role in shaping the surface of Earth and other planets. Volcanic eruptions are perhaps the most dramatic events on Earth, and are of intrinsic interest to students, youth, and adults. Topics involving volcanoes are a part of the national science education benchmarks for understanding the Earth's composition and structure for grades 6-8 (the process of creating landforms) and grades 9-12 (the effects of movement of crustal plates). Natural events on Earth coupled with exciting discoveries in space can serve to heighten the awareness of these phenomena and provide learning opportunities for real world applications of science. Educational applications for youth to compare volcanic activity on Io and Earth have been done through NASA-sponsored field trip workshops to places such as Yellowstone National Park (allowing educators to experience environments similar to those on other worlds), targeted classroom and hands-on activities, special interest books, and other resources. A sampling of such activities will be presented, and discussion invited on other related developmentally appropriate resources and activities.

  7. Explosive Volcanic Activity at Extreme Depths: Evidence from the Charles Darwin Volcanic Field, Cape Verdes

    Science.gov (United States)

    Kwasnitschka, T.; Devey, C. W.; Hansteen, T. H.; Freundt, A.; Kutterolf, S.

    2013-12-01

    Volcanic eruptions on the deep sea floor have traditionally been assumed to be non-explosive as the high-pressure environment should greatly inhibit steam-driven explosions. Nevertheless, occasional evidence both from (generally slow-) spreading axes and intraplate seamounts has hinted at explosive activity at large water depths. Here we present evidence from a submarine field of volcanic cones and pit craters called Charles Darwin Volcanic Field located at about 3600 m depth on the lower southwestern slope of the Cape Verdean Island of Santo Antão. We examined two of these submarine volcanic edifices (Tambor and Kolá), each featuring a pit crater of 1 km diameter, using photogrammetric reconstructions derived from ROV-based imaging followed by 3D quantification using a novel remote sensing workflow, aided by sampling. The measured and calculated parameters of physical volcanology derived from the 3D model allow us, for the first time, to make quantitative statements about volcanic processes on the deep seafloor similar to those generated from land-based field observations. Tambor cone, which is 2500 m wide and 250 m high, consists of dense, probably monogenetic medium to coarse-grained volcaniclastic and pyroclastic rocks that are highly fragmented, probably as a result of thermal and viscous granulation upon contact with seawater during several consecutive cycles of activity. Tangential joints in the outcrops indicate subsidence of the crater floor after primary emplacement. Kolá crater, which is 1000 m wide and 160 m deep, appears to have been excavated in the surrounding seafloor and shows stepwise sagging features interpreted as ring fractures on the inner flanks. Lithologically, it is made up of a complicated succession of highly fragmented deposits, including spheroidal juvenile lapilli, likely formed by spray granulation. It resembles a maar-type deposit found on land. The eruption apparently entrained blocks of MORB-type gabbroic country rocks with

  8. In-situ monitoring of deformation of clayey and volcanic sequences in the lacustrine plain of Iztapalapa, Mexico City

    Science.gov (United States)

    Carreon-Freyre, D.; Cerca, M.; Barrientos, B.; Gutierrez, R.; Blancas, D.

    2012-12-01

    Major cities of Central Mexico with lowering of land elevation problems are located in inter-volcanic and fault bounded basins within the central Trans-Mexican Volcanic Belt (TMVB). The most representative and studied case of ground deformation is Mexico City, where the Iztapalapa Municipality presents the highest population density. This area is located over the geological contact between the "Sierra de Santa Catarina" volcanic range and a lacustrine plain. Filling of lacustrine basins includes silty and clayey sediments as well as pyroclastic deposits (coarse and fine grained) and volcanic rocks layers. We used Ground Penetrating Radar (GPR) and MASW prospection to evaluate contrasts in the physical properties of fine grained soils and identify geometry of the deformational features and implemented a mechanical system for in situ monitoring in fractured sites. Deformational features in this basin reflect an interplay between the geological history (depositional conditions), load history, seismic activity, and faulting. Plastic mechanical behaviour predominates in these clayey sediments and differential deformation locally triggers brittle fracturing and/or subsidence of the surface. In this work we present the results of monitoring and characterization of ground deformation and fracturing in different sequences, our results show a dynamic interplay between the mechanisms of ground fracturing and the stress history of sedimentary sequences. Relating the mechanical behaviour of the studied sequences with variations of physical and geological properties should be taken into account to estimate land level lowering and risk of fracturing for urban development planning.

  9. Submarine seismic monitoring of El Hierro volcanic eruption with a 3C-geophone string: applying new acquisition and data processing techniques to volcano monitoring

    Science.gov (United States)

    Jurado, Maria Jose; Ripepe, Maurizio; Lopez, Carmen; Blanco, Maria Jose; Crespo, Jose

    2015-04-01

    A submarine volcanic eruption took place near the southernmost emerged land of the El Hierro Island (Canary Islands, Spain), from October 2011 to February 2012. The Instituto Geografico Nacional (IGN) seismic stations network evidenced seismic unrest since July 2011 and was a reference also to follow the evolution of the seismic activity associated with the volcanic eruption. Right after the eruption onset, in October 2011 a geophone string was deployed by the CSIC-IGN to monitor seismic activity. Monitoring with the seismic array continued till May 2012. The array was installed less than 2 km away from the new vol¬cano, next to La Restinga village shore in the harbor from 6 to 12m deep into the water. Our purpose was to record seismic activity related to the volcanic activity, continuously and with special interest on high frequency events. The seismic array was endowed with 8, high frequency, 3 component, 250 Hz, geophone cable string with a separation of 6 m between them. Each geophone consists on a 3-component module based on 3 orthogonal independent sensors that measures ground velocity. Some of the geophones were placed directly on the seabed, some were buried. Due to different factors, as the irregular characteristics of the seafloor. The data was recorded on the surface with a seismometer and stored on a laptop computer. We show how acoustic data collected underwater show a great correlation with the seismic data recorded on land. Finally we compare our data analysis results with the observed sea surface activity (ash and lava emission and degassing). This evidence is disclosing new and innovative tecniques on monitoring submarine volcanic activity. Reference Instituto Geográfico Nacional (IGN), "Serie El Hierro." Internet: http://www.ign.es/ign/resources /volcanologia/HIERRO.html [May, 17. 2013

  10. Glass shards, pumice fragments and volcanic aerosol particles - diagenesis a recorder of volcanic activity?

    Science.gov (United States)

    Obenholzner, J. H.; Schroettner, H.; Poelt, P.; Delgado, H.

    2003-04-01

    Detailed SEM/EDS studies of Triassic (Southern Alps, A, I, Sl) and Miocene (Mixteca Alta, Mexico) tuffs revealed that volcanic glass shards can be replaced by zeolites (analcite), chlorites and smectites preserving the shape of primary shards (1). The Triassic pyroclastic deposits have been incorporated in the pre-Alpine burial diagenesis, the Miocene pyroclastic deposits are bentonites. The volcanologist is impressed by the circumstances that million years old pyroclast relict textures can be sized. Shape parameters obtained by image analysis can be compared with much younger pyroclastic deposits (2). Both deposits have not been effected by shearing. The alteration of pumice fragments of Triassic age is not a simple replacement process. Intergrowth of different illites and chlorites and probably vesicle filling by SiO2 and subsequent overgrowth make a reconstruction sometimes difficult. These processes are accompanied by the formation of REE-, Y- and Zr-bearing minerals as well as with the alteration of zircons. Studies of recently erupted ash from Popocatepetl volcano reveal the presence of a variety of µm-sized contact-metamorphosed clasts being a part of the volcanic ash (3). Such clasts should be present in many older pyroclastic deposits, especially where volcanoes had been situated on massive sedimentary units providing contact metamorphism in the realm of a magma chamber or during magma ascent. Volcanic aerosol particles collected in 1997 from the passively degassing plume of Popocatepetl volcano revealed in FESEM/EDS analysis (H. Schroettner and P. Poelt) a wide spectrum of fluffy, spherical and coagulated spherical particles (µm-sized). Under pre-vacuum conditions they remained stable for ca. 3 years (3). In nature the fate of these particles in the atmosphere is unknown. Are there relicts in marine, lacustrine sediments and ice cores, which could be used as proxies of volcanic activity? (1) Obenholzner &Heiken,1999. Ann.Naturhist.Mus.Wien, 100 A, 13

  11. Volcanic Activities of Hakkoda Volcano after the 2011 Tohoku Earthquake

    Science.gov (United States)

    Yamamoto, M.; Miura, S.

    2014-12-01

    The 2011 Tohoku Earthquake of 11 March 2011 generated large deformation in and around the Japanese islands, and the large crustal deformation raises fear of further disasters including triggered volcanic activities. In this presentation, as an example of such potential triggered volcanic activities, we report the recent seismic activities of Hakkoda volcano, and discuss the relation to the movement of volcanic fluids. Hakkoda volcano is a group of stratovolcanoes at the northern end of Honshu Island, Japan. There are fumaroles and hot springs around the volcano, and phreatic eruptions from Jigoku-numa on the southwestern flank of Odake volcano, which is the highest peak of the volcanic group, were documented in its history. Since just after the occurrence of the Tohokui Earthquake, the seismicity around the volcano became higher, and the migration of hypocenters of volcano-tectonic (VT) earthquakes was observed.In addition to these VT earthquakes, long-period (LP) events started occurring beneath Odake at a depth of about 2-3 km since February, 2013, and subtle crustal deformation caused by deep inflation source was also detected by the GEONET GNSS network around the same time. The spectra of LP events are common between events irrespective of the magnitude of events, and they have several spectral peaks at 6-7 sec, 2-3 sec, 1 sec, and so on. These LP events sometimes occur like a swarm with an interval of several minutes. The characteristics of observed LP events at Hakkoda volcano are similar to those of LP events at other active volcanoes and hydrothermal area in the world, where abundant fluids exist. Our further analysis using far-field Rayleigh radiation pattern observed by NIED Hi-net stations reveals that the source of LP events is most likely to be a nearly vertical tensile crack whose strike is NE-SW direction. The strike is almost perpendicular to the direction of maximum extensional strain estimated from the geodetic analysis, and is almost parallel to

  12. Learning about hydrothermal volcanic activity by modeling induced geophysical changes

    Science.gov (United States)

    Currenti, Gilda M.; Napoli, Rosalba

    2017-05-01

    Motivated by ongoing efforts to understand the nature and the energy potential of geothermal resources, we devise a coupled numerical model (hydrological, thermal, mechanical), which may help in the characterization and monitoring of hydrothermal systems through computational experiments. Hydrothermal areas in volcanic regions arise from a unique combination of geological and hydrological features which regulate the movement of fluids in the vicinity of magmatic sources capable of generating large quantities of steam and hot water. Numerical simulations help in understanding and characterizing rock-fluid interaction processes and the geophysical observations associated with them. Our aim is the quantification of the response of different geophysical observables (i.e. deformation, gravity and magnetic field) to hydrothermal activity on the basis of a sound geological framework (e.g. distribution and pathways of the flows, the presence of fractured zones, caprock). A detailed comprehension and quantification of the evolution and dynamics of the geothermal systems and the definition of their internal state through a geophysical modeling approach are essential to identify the key parameters for which the geothermal system may fulfill the requirements to be exploited as a source of energy. For the sake of illustration only, the numerical computations are focused on a conceptual model of the hydrothermal system of Vulcano Island by simulating a generic 1-year unrest and estimating different geophysical changes. We solved (i) the mass and energy balance equations of flow in porous media for temperature, pressure and density changes, (ii) the elastostatic equation for the deformation field and (iii) the Poisson’s equations for gravity and magnetic potential fields. Under the model assumptions, a generic unrest of 1-year engenders on the ground surface low amplitude changes in the investigated geophysical observables, that are, however, above the accuracies of the modern

  13. Volcano Monitoring and Early Warning on MT Etna, Italy, Using Volcanic Tremor - Methods and Technical Aspects

    Science.gov (United States)

    D'Agostino, Marcello; Di Grazia, Giuseppe; Ferrari, Ferruccio; Langer, Horst; Messina, Alfio; Reitano, Danilo; Spampinato, Salvatore

    2013-04-01

    Recent activity on Mt Etna was characterized by 25 lava fountains occurred on Mt Etna in 2011 and the first semester of 2012. In summer 2012 volcanic activity in a milder form was noticed within the Bocca Nuova crater, before it came to an essential halt in August 2012. Together with previous unrests (e. g., in 2007-08) these events offer rich material for testing automatic data processing and alert issue in the context of volcano monitoring. Our presentation focuses on the seismic background radiation - volcanic tremor - which has a key role in the surveillance of Mt Etna. From 2006 on a multi-station alert system exploiting STA/LTA ratios, has been established in the INGV operative centre of Catania. Besides, also the frequency content has been found to change correspondingly to the type of volcanic activity, and can thus be exploited for warning purposes. We apply Self Organizing Maps and Fuzzy Clustering which offer an efficient way to visualize signal characteristics and its development with time. These techniques allow to identify early stages of eruptive events and automatically flag a critical status before this becomes evident in conventional monitoring techniques. Changes of tremor characteristics are related to the position of the source of the signal. Given the dense seismic network we can base the location of the sources on distribution of the amplitudes across the network. The locations proved to be extremely useful for warning throughout both a flank eruption in 2008 as well as the 2011 lava fountains. During all these episodes a clear migration of tremor sources towards the eruptive centres was revealed in advance. The location of the sources completes the picture of an imminent volcanic unrest and corroborates early warnings flagged by the changes of signal characteristics. Automatic real time data processing poses high demands on computational efficiency, robustness of the methods and stability of data acquisition. The amplitude based multi

  14. 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.

  15. Volcanic monitoring from space using neural networks approach. Simultaneous ash and sulfur dioxide retrievals using multispectral measurements

    Science.gov (United States)

    Piscini, A.; Corradini, S.; Chini, M.; Merucci, L.; Stramondo, S.; Picchiani, M.; Del Frate, F.

    2012-04-01

    In this work a Multi Layer Perceptron Neural Networks (MLPNN) approach has been used for a simultaneous volcanic ash and sulfur dioxide retrievals considering the MODIS measurements. As test case the 2010 Eyjafjallajokull eruption have been considered. A network was built for each parameter to be retrieved. Additionally, for volcanic ash, a network for the classification of "ash image pixels" was implemented, which was then used to mask the estimates. Several network topologies were compared in terms of their performance. Concerning the training phase and networks testing, a set of MODIS images was selected covering the Eyjafjallajokull May events. The classification NNs were trained with the volcanic ash classification map obtained with the Brightness Temperature Difference algorithm, assumed as benchmark. The neural networks for the quantitative estimation of the parameters associated with volcanic ash, mass, effective radius, aerosol optical depth and SO2, were instead trained with maps obtained using consolidated estimation algorithms based on simulated radiances at the top of the atmosphere, generated in turn applying a radiative transfer model to remote sensing data. The networks proved to be very effective in solving the inversion problem related to the estimation of the parameters of the volcanic cloud, settling the crucial issue related to false alarms in the detection of volcanic ash. Furthermore, once the training phase is complete, NNs provide a faster inversion technique, useful for the applications. From this point of view the technique satisfies the need to respond quickly as a result of disastrous natural hazards, such as volcanic eruptions. Future activities include testing the effectiveness of the technique under different lighting conditions (night images) and on other types of multispectral data, such as that provided by high temporal resolution sensors like SEVIRI-MSG, on board the METEOSAT second Generation satellites. The latter would be

  16. Sedimentary response to volcanic activity in the Okinawa Trough since the last deglaciation

    Institute of Scientific and Technical Information of China (English)

    蒋富清; 李安春; 李铁刚

    2010-01-01

    To investigate the relationship between volcanic activity and sediment record on regional and temporal scales,158 surface sediment samples were collected from the East China Sea Shelf to the northern Okinawa Trough (OT),and two cores recovered in the northern and southern OT,respectively.Mineralogy,grain-size,and geochemical analyses of those samples show that:1) volcanic glass,volcanic-type pyroxene,hypersthenes,and magnetite increase in sediment influenced by volcanic activity;2) sediment grain sizes (and...

  17. Monitoring the volcanic unrest of El Hierro (Canary Islands) before the onset of the 2011-2012 submarine eruption

    Science.gov (United States)

    López, C.; Blanco, M. J.; Abella, R.; Brenes, B.; Cabrera Rodríguez, V. M.; Casas, B.; Domínguez Cerdeña, I.; Felpeto, A.; de Villalta, M. Fernández; del Fresno, C.; García, O.; García-Arias, M. J.; García-Cañada, L.; Gomis Moreno, A.; González-Alonso, E.; Guzmán Pérez, J.; Iribarren, I.; López-Díaz, R.; Luengo-Oroz, N.; Meletlidis, S.; Moreno, M.; Moure, D.; de Pablo, J. Pereda; Rodero, C.; Romero, E.; Sainz-Maza, S.; Sentre Domingo, M. A.; Torres, P. A.; Trigo, P.; Villasante-Marcos, V.

    2012-07-01

    On 10 October 2011, a submarine volcanic eruption started 2 km south from El Hierro Island (Spain). Since July 2011 a dense multiparametric monitoring network was deployed all over the island by Instituto Geográfico Nacional (IGN). By the time the eruption started, almost 10000 earthquakes had been located and the deformation analyses showed a maximum deformation of more than 5 cm. Earthquake migration from the north to the south of the island and acceleration of seismicity are in good correlation with changes in the deformation pattern as well as with some anomalies in geochemical and geomagnetic parameters. An earthquake of local magnitude 4.3 at 12 km depth (8 October 2011) and shallower seismicity a day after, preceded the onset of the eruption. This is the first time that a volcanic eruption is fully monitored in the Canary Islands. Data recorded during this unrest episode at El Hierro will contribute to understand reawakening of volcanic activity in this region and others of similar characteristics.

  18. Volcanic SO2 and SiF4 visualization and their ratio monitored using 2-D thermal emission spectroscopy

    Science.gov (United States)

    Stremme, W.; Krueger, A.; Harig, R.; Grutter, M.

    2011-09-01

    The composition and emission rates of volcanic gas plumes provide insight of the geologic internal activity, atmospheric chemistry, aerosol formation and radiative processes around it. Observations are necessary for public security and the aviation industry. Ground-based thermal emission infrared spectroscopy, which uses the radiation of the volcanic gas itself, allows for continuously monitoring during day and night from a save distance. We present measurements on Popocatépetl volcano based on thermal emission spectroscopy during different campaigns between 2006-2009 using a Scanning Infrared Gas Imaging System (SIGIS). The experimental set-up, measurement geometries and analytical algorithms are described. The equipment was operated from a safe distance of 12 km from the volcano at two different spectral resolutions: 0.5 and 4 cm-1. The 2-dimensional scanning capability of the instrument allows for an on-line visualization of the volcanic SO2 plume, animation and determination of its propagation speed. SiF4 was also identified in the infrared spectra recorded at both resolutions. The SiF4/SO2 molecular ratio can be calculated from each image and used as a highly useful parameter to follow changes in volcanic activity. A small Vulcanian eruption was monitored during the night of 16 to 17 November 2008 which was confirmed from the strong ash emission registered around 01:00 a.m. LST (Local Standard Time) and a pronounced SO2 cloud was registered. Enhanced SiF4/SO2 ratios were observed before and after the eruption. A validation of the results from thermal emission measurements with those from absorption spectra of the moon taken at the same time, as well as an error analysis, are presented. The inferred propagation speed from sequential imagees is used to calculate the emission rates at different distances from the crater.

  19. Seismic Activity at tres Virgenes Volcanic and Geothermal Field

    Science.gov (United States)

    Antayhua, Y. T.; Lermo, J.; Quintanar, L.; Campos-Enriquez, J. O.

    2013-05-01

    The volcanic and geothermal field Tres Virgenes is in the NE portion of Baja California Sur State, Mexico, between -112°20'and -112°40' longitudes, and 27°25' to 27°36' latitudes. Since 2003 Power Federal Commission and the Engineering Institute of the National Autonomous University of Mexico (UNAM) initiated a seismic monitoring program. The seismograph network installed inside and around the geothermal field consisted, at the beginning, of Kinemetrics K2 accelerometers; since 2009 the network is composed by Guralp CMG-6TD broadband seismometers. The seismic data used in this study covered the period from September 2003 - November 2011. We relocated 118 earthquakes with epicenter in the zone of study recorded in most of the seismic stations. The events analysed have shallow depths (≤10 km), coda Magnitude Mc≤2.4, with epicentral and hypocentral location errors geothermal explotation zone where there is a system NW-SE, N-S and W-E of extensional faults. Also we obtained focal mechanisms for 38 events using the Focmec, Hash, and FPFIT methods. The results show normal mechanisms which correlate with La Virgen, El Azufre, El Cimarron and Bonfil fault systems, whereas inverse and strike-slip solutions correlate with Las Viboras fault. Additionally, the Qc value was obtained for 118 events. This value was calculated using the Single Back Scattering model, taking the coda-waves train with window lengths of 5 sec. Seismograms were filtered at 4 frequency bands centered at 2, 4, 8 and 16 Hz respectively. The estimates of Qc vary from 62 at 2 Hz, up to 220 at 16 Hz. The frequency-Qc relationship obtained is Qc=40±2f(0.62±0.02), representing the average attenuation characteristics of seismic waves at Tres Virgenes volcanic and geothermal field. This value correlated with those observed at other geothermal and volcanic fields.

  20. The search for active release of volcanic gases on Mars

    Science.gov (United States)

    Khayat, Alain; Villanueva, Geronimo; Mumma, Michael; Tokunaga, Alan

    2015-11-01

    The study of planetary atmospheres by means of spectroscopy is important for understanding their origin and evolution. The presence of short-lived trace gases in the martian atmosphere would imply recent production, for example, by ongoing geologic activity. On Earth, sulfur dioxide (SO2), sulfur monoxide (SO) and hydrogen sulfide (H2S) are the main sulfur-bearing gases released during volcanic outgassing. Carbonyl sulfide (OCS), also released from some volcanoes on Earth (e.g., Erebus and Nyiragongo), could be formed by reactions involving SO2 or H2S inside magma chambers. We carried out the first ground-based, semi-simultaneous, multi-band and multi-species search for such gases above the Tharsis and Syrtis volcanic regions on Mars. The submillimeter search extended between 23 November 2011 and 13 May 2012 which corresponded to Mars’ mid Northern Spring and early Northern Summer seasons (Ls = 34-110°). The strong submillimeter rotational transitions of SO2, SO and H2S were targeted using the high-resolution heterodyne receiver (aka Barney) on the Caltech Submillimeter Observatory. We reached sensitivities sufficient to detect a volcanic release on Mars that is 4% of the SO2 released continuously from Kilauea volcano in Hawaii, or 5% that of the Masaya volcano in Nicaragua. The infrared search covered OCS in its combination band (ν2+ν3) at 3.42 μm at two successive Mars years, during Mars’ late Northern Spring and mid Northern Summer seasons, spanning Ls= 43º and Ls= 147º. The targeted volcanic districts were observed during the two intervals, 14 Dec. 2011 to 6 Jan. 2012 in the first year, and 30 May 2014 to 16 June 2014 in the second year, using the high resolution infrared spectrometer (CSHELL) on NASA’s Infrared Telescope Facility (NASA/IRTF). We will present our results and discuss their implications for current volcanic outgassing activity on the red planet. We gratefully acknowledge support from the NASA Planetary Astronomy Program under NASA

  1. The role of petrology in defining volcanic hazards and designing monitoring systems

    Science.gov (United States)

    Smith, I. E.; Turner, M. B.; Price, R. C.; Cronin, S. J.

    2011-12-01

    Petrology is the study of magmatic systems; physical volcanology investigates processes of eruption. Physical volcanology provides the pre-eminent underpinning of the practical business of defining hazard scenarios, planning mitigation and designing monitoring strategies. Recent research in a variety of volcanic settings has demonstrated an important link between the petrologic processes that at a fundamental level drive the behavior of volcanoes and the processes that determine the eruptive style of a volcano. Together these define the hazards that arise from volcanic eruptions. Petrological studies of volcanoes are typically based on a study of lava because coherent rock is less vulnerable to weathering and alteration and is more durable in the geological record. Pyroclastic materials are commonly friable and glassy, are more easily eroded, and are more difficult to use in the analytical techniques that have become the staple basis of petrological studies. However, pyroclastic materials represent a complementary but different part of the magmatic story and it is only by integrating both effusive and explosive components of an eruption sequence that a complete picture of the behavior of the system feeding a volcano can be gained. Andesitic strato-cones are made up of a cone-building facies consisting mainly of primary magmatic products and usually dominated by lava flows because pyroclastic material is easily eroded from the slopes of a steep cone. The surrounding ring plain facies includes primary pyroclastic deposits but is typically dominated by redistributed material in the form of debris flow and lahar deposits together with reworked fluvial material. The deposits of each of these two facies are assembled on different time scales and they contain different aspects of the record of the evolution of the magmatic system that gave rise to them. An important practical consequence of this is that different parts of the geochemical record of the system can occur in

  2. Preliminary Study of UAS Equipped with Thermal Camera for Volcanic Geothermal Monitoring in Taiwan.

    Science.gov (United States)

    Chio, Shih-Hong; Lin, Cheng-Horng

    2017-07-18

    Thermal infrared cameras sense the temperature information of sensed scenes. With the development of UASs (Unmanned Aircraft Systems), thermal infrared cameras can now be carried on a quadcopter UAV (Unmanned Aircraft Vehicle) to appropriately collect high-resolution thermal images for volcanic geothermal monitoring in a local area. Therefore, the quadcopter UAS used to acquire thermal images for volcanic geothermal monitoring has been developed in Taiwan as part of this study to overcome the difficult terrain with highly variable topography and extreme environmental conditions. An XM6 thermal infrared camera was employed in this thermal image collection system. The Trimble BD970 GNSS (Global Navigation Satellite System) OEM (Original Equipment Manufacturer) board was also carried on the quadcopter UAV to gather dual-frequency GNSS observations in order to determine the flying trajectory data by using the Post-Processed Kinematic (PPK) technique; this will be used to establish the position and orientation of collected thermal images with less ground control points (GCPs). The digital surface model (DSM) and thermal orthoimages were then produced from collected thermal images. Tests conducted in the Hsiaoyukeng area of Taiwan's Yangmingshan National Park show that the difference between produced DSM and airborne LIDAR (Light Detection and Ranging) data are about 37% between -1 m and 1 m, and 66% between -2 m and 2 m in the area surrounded by GCPs. As the accuracy of thermal orthoimages is about 1.78 m, it is deemed sufficient for volcanic geothermal monitoring. In addition, the thermal orthoimages show some phenomena not only more globally than do the traditional methods for volcanic geothermal monitoring, but they also show that the developed system can be further employed in Taiwan in the future.

  3. Preliminary Study of UAS Equipped with Thermal Camera for Volcanic Geothermal Monitoring in Taiwan

    Directory of Open Access Journals (Sweden)

    Shih-Hong Chio

    2017-07-01

    Full Text Available Thermal infrared cameras sense the temperature information of sensed scenes. With the development of UASs (Unmanned Aircraft Systems, thermal infrared cameras can now be carried on a quadcopter UAV (Unmanned Aircraft Vehicle to appropriately collect high-resolution thermal images for volcanic geothermal monitoring in a local area. Therefore, the quadcopter UAS used to acquire thermal images for volcanic geothermal monitoring has been developed in Taiwan as part of this study to overcome the difficult terrain with highly variable topography and extreme environmental conditions. An XM6 thermal infrared camera was employed in this thermal image collection system. The Trimble BD970 GNSS (Global Navigation Satellite System OEM (Original Equipment Manufacturer board was also carried on the quadcopter UAV to gather dual-frequency GNSS observations in order to determine the flying trajectory data by using the Post-Processed Kinematic (PPK technique; this will be used to establish the position and orientation of collected thermal images with less ground control points (GCPs. The digital surface model (DSM and thermal orthoimages were then produced from collected thermal images. Tests conducted in the Hsiaoyukeng area of Taiwan’s Yangmingshan National Park show that the difference between produced DSM and airborne LIDAR (Light Detection and Ranging data are about 37% between −1 m and 1 m, and 66% between −2 m and 2 m in the area surrounded by GCPs. As the accuracy of thermal orthoimages is about 1.78 m, it is deemed sufficient for volcanic geothermal monitoring. In addition, the thermal orthoimages show some phenomena not only more globally than do the traditional methods for volcanic geothermal monitoring, but they also show that the developed system can be further employed in Taiwan in the future.

  4. Assessing and optimizing the performance of infrasound networks to monitor volcanic eruptions

    Science.gov (United States)

    Tailpied, Dorianne; Le Pichon, Alexis; Marchetti, Emanuele; Assink, Jelle; Vergniolle, Sylvie

    2017-01-01

    We propose a numerical modeling technique based on a frequency-dependent attenuation relation to assess, quantify and optimize the performance of any arbitrary infrasound network to monitor explosive sources such as volcanic eruptions. Simulations are further enhanced by including realistic sources and propagation effects. We apply our approach to both hemispheres by considering the Euro-Mediterranean and the Eastern Australian regions. In these regions, we use quasi-permanent infrasound signals from Mt. Etna recorded in Tunisia and from Mt. Yasur recorded in New Caledonia. These well-instrumented volcanoes offer a unique opportunity to validate our attenuation model. In particular, accurate comparisons between near- and far-field recordings demonstrate the potential of the proposed methodology to remotely monitor volcanoes. A good agreement is found between modeled and observed results, especially when incorporating representative 10 m s-1 wind perturbations in the atmospheric specifications according to previous campaign measurements. To optimize the network layout in order to ensure the best monitoring of the volcanoes, we proceed through a grid search to find optimum locations of an additional array. We show that adding one array at an appropriate location in both regions under study could significantly improve detections half of the year. The application of the proposed methodology can provide in near real-time a realistic confidence level of volcanic eruption detections, useful to mitigate the risk of aircrafts encountering volcanic ash.

  5. Planning the improvement of seismic monitoring in a volcanic supersite: experience on Mt. Etna

    Science.gov (United States)

    D'Alessandro, Antonino; Scarfi, Luciano; Scaltrito, Antonio; Aiesi, Giampiero; Di Prima, Sergio; Ferrari, Ferruccio; Rapisarda, Salvatore

    2013-04-01

    Etna is one of the most active volcanoes in the world and one of the most intriguing natural laboratories for the understanding of eruptive processes and lava uprising in basalt-type volcanic environments; indeed, it is considered, by the scientific international community, together with the Vesuvius and the Hawaiian Islands, as a volcanic supersite. Its activity is continuously monitored by the Osservatorio Etneo of the Istituto Nazionale di Geofisica e Vulcanologia (INGV), by means of an array of integrated multidisciplinary techniques. In particular, Etna seismicity is recorded by a dense local seismic network (ESN- Etna Seismic Network), which, nowadays, consists of about 40 real-time seismic stations, many of which equipped with broadband velocity and accelerometer sensors. The data are analyzed routinely in detail by the Osservatorio Etneo staff, producing daily and periodic reports and bulletins of the earthquakes located in the whole Sicily and southern Calabria region. In the last decades, seismological observations provided important information on both the dynamics and internal structure of the volcano, in addition to their interaction with the regional tectonic structures. In the last year, in the framework of the VULCAMED project, an INGV workgroup has taken on the task of developing the existing seismic network through the installation of new measurement stations. By considering the spatial distribution of earthquakes in the area, the presence of structures known as seismically active and through extensive geological-geophysical surveys, ten potential new sites were identified. In the following months, some of these sites will complement the existing network. The choice of optimal sites must clearly be made through a careful analysis of environmental noise, of the possible logistics, technical and broadcast problems, but must also take into account the geometry of the existing seismic network. For this purpose, we applied the Seismic Network

  6. Monitoring the Eyjafjöll volcanic plume using OPGC platforms : remote sensing and in-situ measurements

    Science.gov (United States)

    Labazuy, Philippe; Gouhier, Mathieu; Hervo, Maxime; Freville, Patrick; Quehennen, Boris; Donnadieu, Frank; Guehenneux, Yannick; Cacault, Philippe; Colomb, Aurélie; Gayet, Jean-François; Pichon, Jean-Marc; Rivet, Sandrine; Schwarzenböck, Alfons; Sellegri, Karine

    2010-05-01

    OPGC (Observatoire de Physique du Globe de Clermont-Ferrand) presents a unique combination of knowledge in volcanology and atmosphere physics, for the tracking and the monitoring of volcanic plumes. These competences interact through the combination of the mastering of Lidar and radar techniques; gas and aerosol measurement (in-situ and airborne) by the Laboratoire de Météorologie Physique (LaMP,OPGC) and the expertise of the Laboratoire Magmas et Volcans (LMV,OPGC) in eruption dynamics and spatial remote sensing. Platforms for observations benefit from the technical support and expertise of the OPGC staff. HOTVOLC group is dedicated to the near-real-time monitoring of thermal anomalies related to the eruptive activity of volcanoes. The main goal of HOTVOLC deals with estimation of quantitative parameters that give stringent constraints on ash plumes dynamics, from the vent to the atmosphere. Datas from HOTVOLC give near -real time monitoring of ash plume, and its height, crucial parameter for predictive models and risk assessment. The height of the plume of Eyjafjöll on April 15 2010 at 12:00 UTC was estimated at 5000-6500 m, in accordance with ground observations and Lidar data. TERRA MODIS and AURA OMI sensors were used for the daily quantitative estimation of ash and SO2 burden , respectively. Two peaks of ash and SO2 emissions occurring on April 15 (100 kt and 8 kt) and 19 (170 kt and 12 kt) were determined. HOTVOLC is involved in the monitoring of the eruption at Eyjafjöll(Iceland) and belongs to a volcano alert group, at the request of the MEEDDM (French Ministry for ecology, energy, sustainable development and sea). LIDAR at the OPGC, is a Rayleigh-Mie LIDAR emitting at 355nm, with parallel and crossed polarization channels. On April 19, a layer of depolarizing particles i.e.non-spherical particles was observed at 3000 m a.s.l, with maximum thickness of 500m. The instrumented station at the top of the Puy de Dôme allows measurements of gas-phase and of

  7. Galileo SSI Observations of Volcanic Activity at Tvashtar Catena, Io

    Science.gov (United States)

    Milazzo, M. P.; Keszthely, L. P.; Radebaugh, J.; Davies, A. G.; Turtle, E. P.; Geissler, P.; Klaasen, K. P.; McEwen, A. S.

    2005-01-01

    Introduction: We report on the analysis of the Galileo SSI's observations of the volcanic activity at Tvashtar Catena, Io as discussed by Milazzo et al. Galileo's Solid State Imager (SSI) observed Tvashtar Catena (63 deg N, 120 deg W) four times between November 1999 and October 2001, providing a unique look at the distinctive high latitude volcanism on Io. The November 1999 observation spatially resolved, for the first time, an active extraterrestrial fissure eruption. The brightness temperature of the lavas at the November 1999 fissure eruption was 1300 K. The second observation (orbit I27, February 2000) showed a large (approx. 500 sq km) region with many, small spots of hot, active lava. The third observation was taken in conjunction with a Cassini observation in December 2000 and showed a Pele-like plume deposition ring, while the Cassini images revealed a 400 km high Pele-type plume above the Catena. The final Galileo SSI observation of Tvashtar was acquired in October 2001, and all obvious (to SSI) activity had ceased, although data from Galileo's Near Infrared Mapping Spectrometer (NIMS) indicated that there was still significant thermal emission from the Tvashtar region. We have concentrated on analyzing the style of eruption during orbit I27 (February 2000). Comparison with a lava flow cooling model indicates that the behavior of the Tvashtar eruption during I27 does not match that of "simple" advancing lava flows. Instead, it may be an active lava lake or a complex set of lava flows with episodic, overlapping (in time and space) eruptions.

  8. A Preliminary Study of the Types of Volcanic Earthquakes and Volcanic Activity at the Changbaishan Tianchi Volcano

    Institute of Scientific and Technical Information of China (English)

    Ming Yuehong; Su Wei; Fang Lihua

    2006-01-01

    Since 2002, a significant increase in seismicity, obvious ground deformation and geochemical anomalies have been observed in the Changbaishan Tianchi volcanic area. A series felt earthquakes occur near the caldera, causing great influence to society. In this paper, the types of volcanic earthquakes recorded by the temporal seismic network since 2002 have been classified by analyzing the spectrum, time-frequency characteristics and seismic waveforms at different stations. The risk of volcano eruptions was also estimated. Our results show that almost all earthquakes occurring in Tianchi volcano are volcanic-tectonic earthquakes. The low frequency seismic waveforms observed at a few stations may be caused by local mediums, and have no relation with long-period events. Although the level of seismicity increased obviously and earthquake swarms occurred more frequently than before, we considered that the magma activity is still in its early stage and the eruption risk of Changbaishan Tianchi volcano is still iow in the near future.

  9. Near real-time monitoring of volcanic surface deformation from GPS measurements at Long Valley Caldera, California

    Science.gov (United States)

    Ji, Kang Hyeun; Herring, Thomas A.; Llenos, Andrea L.

    2013-01-01

    Long Valley Caldera in eastern California is an active volcanic area and has shown continued unrest in the last three decades. We have monitored surface deformation from Global Positioning System (GPS) data by using a projection method that we call Targeted Projection Operator (TPO). TPO projects residual time series with secular rates and periodic terms removed onto a predefined spatial pattern. We used the 2009–2010 slow deflation as a target spatial pattern. The resulting TPO time series shows a detailed deformation history including the 2007–2009 inflation, the 2009–2010 deflation, and a recent inflation that started in late-2011 and is continuing at the present time (November 2012). The recent inflation event is about four times faster than the previous 2007–2009 event. A Mogi source of the recent event is located beneath the resurgent dome at about 6.6 km depth at a rate of 0.009 km3/yr volume change. TPO is simple and fast and can provide a near real-time continuous monitoring tool without directly looking at all the data from many GPS sites in this potentially eruptive volcanic system.

  10. Near real-time monitoring of volcanic surface deformation from GPS measurements at Long Valley Caldera, California

    Science.gov (United States)

    Ji, Kang Hyeun; Herring, Thomas A.; Llenos, Andrea L.

    2013-03-01

    Long Valley Caldera in eastern California is an active volcanic area and has shown continued unrest in the last three decades. We have monitored surface deformation from Global Positioning System (GPS) data by using a projection method that we call Targeted Projection Operator (TPO). TPO projects residual time series with secular rates and periodic terms removed onto a predefined spatial pattern. We used the 2009-2010 slow deflation as a target spatial pattern. The resulting TPO time series shows a detailed deformation history including the 2007-2009 inflation, the 2009-2010 deflation, and a recent inflation that started in late-2011 and is continuing at the present time (November 2012). The recent inflation event is about four times faster than the previous 2007-2009 event. A Mogi source of the recent event is located beneath the resurgent dome at about 6.6 km depth at a rate of 0.009 km3/yr volume change. TPO is simple and fast and can provide a near real-time continuous monitoring tool without directly looking at all the data from many GPS sites in this potentially eruptive volcanic system.

  11. Unsupervised Change Detection for Geological and Ecological Monitoring via Remote Sensing: Application on a Volcanic Area

    Science.gov (United States)

    Falco, N.; Pedersen, G. B. M.; Vilmunandardóttir, O. K.; Belart, J. M. M. C.; Sigurmundsson, F. S.; Benediktsson, J. A.

    2016-12-01

    The project "Environmental Mapping and Monitoring of Iceland by Remote Sensing (EMMIRS)" aims at providing fast and reliable mapping and monitoring techniques on a big spatial scale with a high temporal resolution of the Icelandic landscape. Such mapping and monitoring will be crucial to both mitigate and understand the scale of processes and their often complex interlinked feedback mechanisms.In the EMMIRS project, the Hekla volcano area is one of the main sites under study, where the volcanic eruptions, extreme weather and human activities had an extensive impact on the landscape degradation. The development of innovative remote sensing approaches to compute earth observation variables as automatically as possible is one of the main tasks of the EMMIRS project. Furthermore, a temporal remote sensing archive is created and composed by images acquired by different sensors (Landsat, RapidEye, ASTER and SPOT5). Moreover, historical aerial stereo photos allowed decadal reconstruction of the landscape by reconstruction of digital elevation models. Here, we propose a novel architecture for automatic unsupervised change detection analysis able to ingest multi-source data in order to detect landscape changes in the Hekla area. The change detection analysis is based on multi-scale analysis, which allows the identification of changes at different level of abstraction, from pixel-level to region-level. For this purpose, operators defined in mathematical morphology framework are implemented to model the contextual information, represented by the neighbour system of a pixel, allowing the identification of changes related to both geometrical and spectral domains. Automatic radiometric normalization strategy is also implemented as pre-processing step, aiming at minimizing the effect of different acquisition conditions. The proposed architecture is tested on multi-temporal data sets acquired over different time periods coinciding with the last three eruptions (1980-1981, 1991

  12. Application of Geographical Information Systems to Lahar Hazard Assessment on an Active Volcanic System

    OpenAIRE

    2010-01-01

    Lahars (highly dynamic mixtures of volcanic debris and water) have been responsible for some of the most serious volcanic disasters and have killed tens of thousands of people in recent decades. Despite considerable lahar model development in the sciences, many research tools have proved wholly unsuitable for practical application on an active volcanic system where it is difficult to obtain field measurements. In addition, geographic information systems are tools that offer a great potenti...

  13. Hydrothermal reservoir beneath Taal Volcano (Philippines): Implications to volcanic activity

    Science.gov (United States)

    Nagao, T.; Alanis, P. B.; Yamaya, Y.; Takeuchi, A.; Bornas, M. V.; Cordon, J. M.; Puertollano, J.; Clarito, C. J.; Hashimoto, T.; Mogi, T.; Sasai, Y.

    2012-12-01

    Taal Volcano is one of the most active volcanoes in the Philippines. The first recorded eruption was in 1573. Since then it has erupted 33 times resulting in thousands of casualties and large damages to property. In 1995, it was declared as one of the 15 Decade Volcanoes. Beginning in the early 1990s it has experienced several phases of abnormal activity, including seismic swarms, episodes of ground deformation, ground fissuring and hydrothermal activities, which continues up to the present. However, it has been noted that past historical eruptions of Taal Volcano may be divided into 2 distinct cycles, depending on the location of the eruption center, either at Main Crater or at the flanks. Between 1572-1645, eruptions occurred at the Main Crater, in 1707 to 1731, they occurred at the flanks. In 1749, eruptions moved back to the Main Crater until 1911. During the 1965 and until the end of the 1977 eruptions, eruptive activity once again shifted to the flanks. As part of the PHIVOLCS-JICA-SATREPS Project magnetotelluric and audio-magnetotelluric surveys were conducted on Volcano Island in March 2011 and March 2012. Two-dimensional (2-D) inversion and 3-D forward modeling reveals a prominent and large zone of relatively high resistivity between 1 to 4 kilometers beneath the volcano almost directly beneath the Main Crater, surrounded by zones of relatively low resistivity. This anomalous zone of high resistivity is hypothesized to be a large hydrothermal reservoir filled with volcanic fluids. The presence of this large hydrothermal reservoir could be related to past activities of Taal Volcano. In particular we believe that the catastrophic explosion described during the 1911 eruption was the result of the hydrothermal reservoir collapsing. During the cycle of Main Crater eruptions, this hydrothermal reservoir is depleted, while during a cycle of flank eruptions this reservoir is replenished with hydrothermal fluids.

  14. Catastrophic volcanism

    Science.gov (United States)

    Lipman, Peter W.

    1988-01-01

    Since primitive times, catastrophes due to volcanic activity have been vivid in the mind of man, who knew that his activities in many parts of the world were threatened by lava flows, mudflows, and ash falls. Within the present century, increasingly complex interactions between volcanism and the environment, on scales not previously experienced historically, have been detected or suspected from geologic observations. These include enormous hot pyroclastic flows associated with collapse at source calderas and fed by eruption columns that reached the stratosphere, relations between huge flood basalt eruptions at hotspots and the rifting of continents, devastating laterally-directed volcanic blasts and pyroclastic surges, great volcanic-generated tsunamis, climate modification from volcanic release of ash and sulfur aerosols into the upper atmosphere, modification of ocean circulation by volcanic constructs and attendent climatic implications, global pulsations in intensity of volcanic activity, and perhaps triggering of some intense terrestrial volcanism by planetary impacts. Complex feedback between volcanic activity and additional seemingly unrelated terrestrial processes likely remains unrecognized. Only recently has it become possible to begin to evaluate the degree to which such large-scale volcanic processes may have been important in triggering or modulating the tempo of faunal extinctions and other evolutionary events. In this overview, such processes are examined from the viewpoint of a field volcanologist, rather than as a previous participant in controversies concerning the interrelations between extinctions, impacts, and volcanism.

  15. Io's Diverse Styles of Volcanic Activity: Results from Galileo NIMS

    Science.gov (United States)

    Lopes, R. M. C.; Smythe, W. D.; Kamp, L. W.; Doute, S.; Carlson, R.; McEwen, A.; Geissler, P.

    2001-01-01

    Observations by Galileo's Near-Infrared Mapping Spectrometer were used to map the thermal structure of several of Io's hot spots, revealing different styles of volcanism Additional information is contained in the original extended abstract..

  16. Impact of the Popocatepetl's volcanic activity on the air quality of Puebla City, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Juarez, A. [Facultad de Ciencias Fisico Matematicas, Universidad Autonoma de Puebla, Puebla (Mexico); Gay, C. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, UNAM, Mexico, D.F. (Mexico); Flores, Y. [Facultad de Ciencias Fisico Matematicas, Universidad Autonoma de Puebla, Puebla (Mexico)

    2005-01-01

    In this work we report measurements of atmospheric pollutants in Puebla City, including those registered during the period characterized by intense volcanic activity from Popocatepetl volcano between December 2000 and January 2001. We used a gaussian air dispersion model to calculate the impact of sulfur compounds from volcanic emissions on the measurements of these compounds in the stations belonging to Puebla City Atmospheric Monitoring Network. The data show that during the analyzed period, this volcanic emissions affected the air quality, increasing the indexes of PM{sub 1}0, CO and sulfur compounds. Also, the results of applying a Gaussian air dispersion model to these sulfur compounds explains the measurements from Tecnologico station for days with intense volcanic activity and wind coming from the volcano to Puebla City. [Spanish] En este trabajo se reportan mediciones de contaminantes atmosfericos en la ciudad de Puebla, incluyendo las registradas durante el periodo caracterizado por una intensa actividad del volcan Popocatepetl, entre diciembre de 200 y enero de 2001. Aplicamos un modelo de dispersion gaussiano para calcular el impacto de las emisiones volcanicas de compuestos de azufre en las mediciones de estos compuestos en las estaciones de la Red de Monitoreo Atmosferico de la ciudad de Puebla. Los datos muestran que durante el periodo analizado, las emisiones volcanicas afectaron la calidad del aire incrementando los indices de PM{sub 1}0, CO y compuestos de azufre. Ademas, los resultados del modelo gaussiano de dispersion del aire para los compuestos de azufre, explican las mediciones de la estacion Tecnologico para los dias con intensa actividad volcanica y viento viniendo del volcan hacia la ciudad de Puebla.

  17. Value activity monitoring

    OpenAIRE

    de Alencar Silva, P.

    2013-01-01

    Abstract: Current value modeling ontologies are grounded on the economic premise that profit sharing is a critical condition to be assessed during the configuration of a value constellation. Such a condition ought to be reinforced through a monitoring mechanism design, since a value model expresses only promises (but not assurances) of value creation. Hence there is a need to extend current value modeling ontologies with a monitoring ontology. This ontology will enable business practitioners ...

  18. Evidences of active and ancient Volcanism on Mars. A review

    Directory of Open Access Journals (Sweden)

    P. HÉDERVÂRI

    1972-06-01

    Full Text Available Since t h e end of t h e last Century some observations concerning
    flare-phenomena on Mars were reported by different explorers. According
    to the opinion of Heuseler ( u . 1 2 . 1 3 , Katterfeld (", Saheki (16,
    Sato (16 and other authors, t h e respective light-phenomena might have been
    t h e signs of active volcanoes on t h e planet. Grey clouds, observed b y Japanese
    explorers as well as by Capen (3, may be also a t t r i b u t e d to volcanic
    o u t b u r s t s . There are some observations, carried out by Dollfus (10, which
    revealed the existence of relatively small, white, persistent clouds over cert
    a i n Martian regions which can be i n t e r p r e t e d as w h i t e vapour-clouds emitted
    by Martian volcanoes.
    The author of the present s t u d y has investigated the distribution of
    t h e s e phenomena over t h e Martian surface and found t h a t t h e distribution
    is not random. The events occurred — in t h e overwhelming m a j o r i t y of the
    cases — 011 a r e a s which are lying along t h e t r a n s i t i o n a l region between dark
    and bright territories. It is i m p o r t a n t to note t h a t many of t h e lunar transient
    events (probably postvolcanic phenomena have a similar position 011
    t h e lunar surface, t h a t is t h e y can be found mostly at t h e border of lunar
    c o n t i n e n t s or basins respectively. On the other hand the most important
    volcanic zones of t h e E a r t h are also t o be found along t h e edges of t h e Pacific
    basin.

  19. Complex explosive volcanic activity on the Moon within Oppenheimer crater

    Science.gov (United States)

    Bennett, Kristen A.; Horgan, Briony H. N.; Gaddis, Lisa R.; Greenhagen, Benjamin T.; Allen, Carlton C.; Hayne, Paul O.; Bell, James F.; Paige, David A.

    2016-07-01

    Oppenheimer crater is a floor-fractured crater located within the South Pole-Aitken basin on the Moon, and exhibits more than a dozen localized pyroclastic deposits associated with the fractures. Localized pyroclastic volcanism on the Moon is thought to form as a result of intermittently explosive Vulcanian eruptions under low effusion rates, in contrast to the higher-effusion rate, Hawaiian-style fire fountaining inferred to form larger regional deposits. We use Lunar Reconnaissance Orbiter Camera images and Diviner Radiometer mid-infrared data, Chandrayaan-1 orbiter Moon Mineralogy Mapper near-infrared spectra, and Clementine orbiter Ultraviolet/visible camera images to test the hypothesis that the pyroclastic deposits in Oppenheimer crater were emplaced via Vulcanian activity by constraining their composition and mineralogy. Mineralogically, we find that the deposits are variable mixtures of orthopyroxene and minor clinopyroxene sourced from the crater floor, juvenile clinopyroxene, and juvenile iron-rich glass, and that the mineralogy of the pyroclastics varies both across the Oppenheimer deposits as a whole and within individual deposits. We observe similar variability in the inferred iron content of pyroclastic glasses, and note in particular that the northwest deposit, associated with Oppenheimer U crater, contains the most iron-rich volcanic glass thus far identified on the Moon, which could be a useful future resource. We propose that this variability in mineralogy indicates variability in eruption style, and that it cannot be explained by a simple Vulcanian eruption. A Vulcanian eruption should cause significant country rock to be incorporated into the pyroclastic deposit; however, large areas within many of the deposits exhibit spectra consistent with high abundances of juvenile phases and very little floor material. Thus, we propose that at least the most recent portion of these deposits must have erupted via a Strombolian or more continuous fire

  20. Monitoring Active Volcanos Using Aerial Images and the Orthoview Tool

    Directory of Open Access Journals (Sweden)

    Maria Marsella

    2014-12-01

    Full Text Available In volcanic areas, where it can be difficult to perform direct surveys, digital photogrammetry techniques are rarely adopted for routine volcano monitoring. Nevertheless, they have remarkable potentialities for observing active volcanic features (e.g., fissures, lava flows and the connected deformation processes. The ability to obtain accurate quantitative data of definite accuracy in short time spans makes digital photogrammetry a suitable method for controlling the evolution of rapidly changing large-area volcanic phenomena. The systematic acquisition of airborne photogrammetric datasets can be adopted for implementing a more effective procedure aimed at long-term volcano monitoring and hazard assessment. In addition, during the volcanic crisis, the frequent acquisition of oblique digital images from helicopter allows for quasi-real-time monitoring to support mitigation actions by civil protection. These images are commonly used to update existing maps through a photo-interpretation approach that provide data of unknown accuracy. This work presents a scientific tool (Orthoview that implements a straightforward photogrammetric approach to generate digital orthophotos from single-view oblique images provided that at least four Ground Control Points (GCP and current Digital Elevation Models (DEM are available. The influence of the view geometry, of sparse and not-signalized GCP and DEM inaccuracies is analyzed for evaluating the performance of the developed tool in comparison with other remote sensing techniques. Results obtained with datasets from Etna and Stromboli volcanoes demonstrate that 2D features measured on the produced orthophotos can reach sub-meter-level accuracy.

  1. Experimental study on the effect of calcination on the volcanic ash activity of diatomite

    Science.gov (United States)

    Xiao, Liguang; Pang, Bo

    2017-09-01

    The volcanic ash activity of diatomite was studied under the conditions of aerobic calcination and vacuum calcination by the combined water rate method, it was characterized by XRD, BET and SEM. The results showed that the volcanic ash activity of diatomite under vacuum conditions was higher than that of aerobic calcination, 600°C vacuum calcination 2h, the combined water rate of diatomite-Ca(OH)2-H2O system was increased from 6.24% to 71.43%, the volcanic ash activity reached the maximum value, the specific surface

  2. Effect of volatiles erupted from Mesozoic and Cenozoic volcanic activities on paleo-environmental changes in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on the determination of composition of volcanic volatiles and petrologic estimation of the total mass of volatiles erupted,we showed important advances in the study of the impact of Mesozoic and Cenozoic volcanic activities on paleo-environmental changes in China.The volcanic activities include western Liaoning and Zhangjiakou Mesozoic intermediate-acidic explosive eruptions,southern Tibet and Shanwang Cenozoic volcanism,and Mt.Changbai volcanic eruption around one thousand years ago.The paper predominantly discusses the earth's surface temperature changes,ozone depletion,acidic rain formation and mass mortalities of vertebrate induced by the Mesozoic and Cenozoic volcanism in China.

  3. Value activity monitoring

    NARCIS (Netherlands)

    de Alencar Silva, P.

    2013-01-01

    Current value modeling ontologies are grounded on the economic premise that profit sharing is a critical condition to be assessed during the configuration of a value constellation. Such a condition ought to be reinforced through a monitoring mechanism design, since a value model expresses only promi

  4. Use of Logistic Regression for Forecasting Short-Term Volcanic Activity

    Directory of Open Access Journals (Sweden)

    Mark T. Woods

    2012-08-01

    Full Text Available An algorithm that forecasts volcanic activity using an event tree decision making framework and logistic regression has been developed, characterized, and validated. The suite of empirical models that drive the system were derived from a sparse and geographically diverse dataset comprised of source modeling results, volcano monitoring data, and historic information from analog volcanoes. Bootstrapping techniques were applied to the training dataset to allow for the estimation of robust logistic model coefficients. Probabilities generated from the logistic models increase with positive modeling results, escalating seismicity, and rising eruption frequency. Cross validation yielded a series of receiver operating characteristic curves with areas ranging between 0.78 and 0.81, indicating that the algorithm has good forecasting capabilities. Our results suggest that the logistic models are highly transportable and can compete with, and in some cases outperform, non-transportable empirical models trained with site specific information.

  5. GEOFIM: A WebGIS application for integrated geophysical modeling in active volcanic regions

    Science.gov (United States)

    Currenti, Gilda; Napoli, Rosalba; Sicali, Antonino; Greco, Filippo; Negro, Ciro Del

    2014-09-01

    We present GEOFIM (GEOphysical Forward/Inverse Modeling), a WebGIS application for integrated interpretation of multiparametric geophysical observations. It has been developed to jointly interpret scalar and vector magnetic data, gravity data, as well as geodetic data, from GPS, tiltmeter, strainmeter and InSAR observations, recorded in active volcanic areas. GEOFIM gathers a library of analytical solutions, which provides an estimate of the geophysical signals due to perturbations in the thermal and stress state of the volcano. The integrated geophysical modeling can be performed by a simple trial and errors forward modeling or by an inversion procedure based on NSGA-II algorithm. The software capability was tested on the multiparametric data set recorded during the 2008-2009 Etna flank eruption onset. The results encourage to exploit this approach to develop a near-real-time warning system for a quantitative model-based assessment of geophysical observations in areas where different parameters are routinely monitored.

  6. 2012 volcanic activity in Alaska: summary of events and response of the Alaska Volcano Observatory

    Science.gov (United States)

    Herrick, Julie A.; Neal, Christina A.; Cameron, Cheryl E.; Dixon, James P.; McGimsey, Robert G.

    2014-01-01

    The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, volcanic unrest, or suspected unrest at 11 volcanic centers in Alaska during 2012. Of the two verified eruptions, one (Cleveland) was clearly magmatic and the other (Kanaga) was most likely a single phreatic explosion. Two other volcanoes had notable seismic swarms that probably were caused by magmatic intrusions (Iliamna and Little Sitkin). For each period of clear volcanic unrest, AVO staff increased monitoring vigilance as needed, reviewed eruptive histories of the volcanoes in question to help evaluate likely outcomes, and shared observations and interpretations with the public. 2012 also was the 100th anniversary of Alaska’s Katmai-Novarupta eruption of 1912, the largest eruption on Earth in the 20th century and one of the most important volcanic eruptions in modern times. AVO marked this occasion with several public events.

  7. Monitoring of the volcanic plume based on the post-fit phase residual of PPP analysis and SNR data

    Science.gov (United States)

    Ohta, Yusaku; Iguchi, Masato

    2016-04-01

    A volcanic explosion is one of the largest energy-release phenomena on earth. For example, vulcanian eruptions usually eject large amounts of rock mass, tephra, and volcanic ash. Ash fall from such events can seriously affect the structural integrity of buildings, in addition to disrupting land and air traffic. Therefore, the monitoring and prediction of ash fall is very important. In this study, using data from a dense GNSS network, we investigated the spatiotemporal development of the volcanic plume ejected by the vulcanian eruption in Sakurajima, southwestern Japan on July 24, 2012. We extracted the post-fit phase residuals (PPR) of ionosphere-free linear combinations for each satellite based on the precise point positioning approach. Temporal and spatial PPR anomalies clearly detected the movement of the volcanic plume. The maximum height of the crossing points of anomalous PPR paths was determined to be approximately 4000 m. We then compared the PPR with the signal-to-noise ratio (SNR) anomalies. Only the path passing just above the crater showed significant change in the SNR value, suggesting that the volcanic ash and the water vapor within the volcanic plume became separated after reaching a high altitude because of ash fall during the plume's lateral movement. In the presentation, we will introduce the eruption in Shin-dake (Kuchinoerabu island, southwestern Japan) on May 29, 2015 based on the SNR data.

  8. 2014 volcanic activity in Alaska: Summary of events and response of the Alaska Volcano Observatory

    Science.gov (United States)

    Cameron, Cheryl E.; Dixon, James P.; Neal, Christina A.; Waythomas, Christopher F.; Schaefer, Janet R.; McGimsey, Robert G.

    2017-09-07

    The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, volcanic unrest or suspected unrest, and seismic events at 18 volcanic centers in Alaska during 2014. The most notable volcanic activity consisted of intermittent ash eruptions from long-active Cleveland and Shishaldin Volcanoes in the Aleutian Islands, and two eruptive episodes at Pavlof Volcano on the Alaska Peninsula. Semisopochnoi and Akutan volcanoes had seismic swarms, both likely the result of magmatic intrusion. The AVO also installed seismometers and infrasound instruments at Mount Cleveland during 2014.

  9. 2010 Volcanic activity in Alaska, Kamchatka, and the Kurile Islands: summary of events and response of the Alaska Volcano Observatory

    Science.gov (United States)

    Neal, Christina A.; Herrick, Julie; Girina, O.A.; Chibisova, Marina; Rybin, Alexander; McGimsey, Robert G.; Dixon, Jim

    2014-01-01

    The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, volcanic unrest or suspected unrest at 12 volcanic centers in Alaska during 2010. The most notable volcanic activity consisted of intermittent ash emissions from long-active Cleveland volcano in the Aleutian Islands. AVO staff also participated in hazard communication regarding eruptions or unrest at seven volcanoes in Russia as part of an ongoing collaborative role in the Kamchatka and Sakhalin Volcanic Eruption Response Teams.

  10. G-EVER Activities and the Next-generation Volcanic Hazard Assessment System

    Science.gov (United States)

    Takarada, S.

    2013-12-01

    The Asia-Pacific Region Global Earthquake and Volcanic Eruption Risk Management (G-EVER) is a consortium of Asia-Pacific geohazard research institutes that was established in 2012. G-EVER aims to formulate strategies to reduce the risks of disasters worldwide caused by the occurrence of earthquakes, tsunamis and volcanic eruptions. G-EVER is working on enhancing collaboration, sharing of resources, and making information on the risks of earthquakes and volcanic eruptions freely available and understandable. The 1st G-EVER International Symposium was held in Tsukuba, Japan in March 11, 2013. The 2nd Symposium is scheduled in Sendai, Tohoku Japan, in Oct. 19-20, 2013. Currently, 4 working groups were proposed in the G-EVER Consortium. The next-generation volcano hazard assessment WG is developing a useful system for volcanic eruption prediction, risk assessment, and evacuation at various eruption stages. The assessment system is based on volcanic eruption history datasets, volcanic eruption database, and numerical simulations. Volcanic eruption histories including precursor phenomena leading to major eruptions of active volcanoes are very important for future prediction of volcanic eruptions. A high quality volcanic eruption database, which contains compilations of eruption dates, volumes, and types, is important for the next-generation volcano hazard assessment system. Proposing international standards on how to estimate the volume of volcanic products is important to make a high quality volcanic eruption database. Spatial distribution database of volcanic products (e.g. tephra and pyroclastic flow distributions), encoded into a GIS based database is necessary for more precise area and volume estimation and risk assessments. The volcanic eruption database is developed based on past eruption results, which only represents a subset of possible future scenarios. Therefore, numerical simulations with controlled parameters are needed for more precise volcanic eruption

  11. Integrating science and education during an international, multi-parametric investigation of volcanic activity at Santiaguito volcano, Guatemala

    Science.gov (United States)

    Lavallée, Yan; Johnson, Jeffrey; Andrews, Benjamin; Wolf, Rudiger; Rose, William; Chigna, Gustavo; Pineda, Armand

    2016-04-01

    In January 2016, we held the first scientific/educational Workshops on Volcanoes (WoV). The workshop took place at Santiaguito volcano - the most active volcano in Guatemala. 69 international scientists of all ages participated in this intensive, multi-parametric investigation of the volcanic activity, which included the deployment of seismometers, tiltmeters, infrasound microphones and mini-DOAS as well as optical, thermographic, UV and FTIR cameras around the active vent. These instruments recorded volcanic activity in concert over a period of 3 to 9 days. Here we review the research activities and present some of the spectacular observations made through this interdisciplinary efforts. Observations range from high-resolution drone and IR footage of explosions, monitoring of rock falls and quantification of the erupted mass of different gases and ash, as well as morphological changes in the dome caused by recurring explosions (amongst many other volcanic processes). We will discuss the success of such integrative ventures in furthering science frontiers and developing the next generation of geoscientists.

  12. Martian volcanism - Additional observations and evidence for pyroclastic activity

    Science.gov (United States)

    West, M.

    1974-01-01

    Inspection of the Mariner 9 B-camera (resolution 100-200 m) and A-camera (resolution 1-2 km) photographs of Mars reveals numerous analogs of terrestrial and lunar volcanic features. In addition to the exceptionally large constructional features in the Tharsis region, many other large and small landforms present probably are related to endogenic processes.

  13. Soil radon measurements as potential tracer of seismic and volcanic activity at Etna

    Science.gov (United States)

    Neri, Marco; Giammanco, Salvatore; Galli, Gianfranco; Ferrera, Elisabetta

    2014-05-01

    Radon is a radioactive noble gas present in all rocks of the Earth. It's used by the scientific community as a tracer of natural phenomena related to outgassing from the soil along faults, fractures and crustal discontinuity. Recently, radon has also been used on active volcanoes such as Etna, both as a precursor of volcanic phenomena as well as in the study of the dynamics of faults. The Istituto Nazionale di Geofisica e Vulcanologia (INGV) performs discrete and continuous measurements of radon from soil at Etna since 2002. First studies concerned measurements of radon and thoron emissions from soil carried out on the E and SW flanks of Etna, in zones characterized by the presence of numerous seismogenic and aseismic faults. The statistical treatment of the geochemical data allowed recognizing anomaly thresholds, producing distribution maps that highlighted a significant spatial correlation between soil gas anomalies and tectonic lineaments. These studies confirmed that mapping the distribution of radon and thoron in soil gas can reveal hidden faults buried by recent soil cover. INGV permanent radon monitoring network was installed in July 2005. First results were obtained during the July 2006 eruption. The radon signal recorded at Torre del Filosofo (TdF, ~2950 m asl) was compared with volcanic tremor and thermal radiance data. The onset of explosive activity and a lava fountaining episode were preceded by some hours with increases in radon activity and more gradual increases in volcanic tremor. After 2006, Etna produced dozens of paroxysmal episodes from a new vent opened on the eastern flank of the Southeast Crater (summit area), that have built up a new, huge pyroclastic cone. In many cases we observed increase in radon activity some hours before the eruptive events. These observations suggest that radon emissions from the TdF zone are sensitive to the local geodynamic pressure induced by magma dynamics in the conduit systems. Other promising results were

  14. Aerosols Monitoring Network to Create a Volcanic ASH Risk Management System in Argentina and Chile

    Directory of Open Access Journals (Sweden)

    Quel Eduardo

    2016-01-01

    Full Text Available Two main decisions were made in Argentina to mitigate the impact of the recent volcanic activity in de country basically affected by the presence of volcanic ash in the air and deposited over the Argentinean territory. The first one was to create a risk management commission were this risk between others were studied, and second to develop new ground based remote sensing technologies to be able to identify and inform the risk close to the airports. In addition the Japanese government program for Science and Technology joint Research Partnership between Argentina, Chile and Japan for Sustainable Development (SATREPS accepted to fund this cooperation due to the potential future utilization of the research outcomes to the benefit of the society. This work present the actual achievements and expected advance of these projects that try to joint efforts between national and international agencies as well as countries on behalf of a better understanding of the risks and a joint collaboration on the mitigation of suspended ashes impact over the aerial navigation.

  15. Aerosols Monitoring Network to Create a Volcanic ASH Risk Management System in Argentina and Chile

    Science.gov (United States)

    Quel, Eduardo; Sugimoto, Nobuo; Otero, Lidia; Jin, Yoshitaka; Ristori, Pablo; Nishizawa, Tomoaki; González, Francisco; Papandrea, Sebastián; Shimizu, Atsushi; Mizuno, Akira

    2016-06-01

    Two main decisions were made in Argentina to mitigate the impact of the recent volcanic activity in de country basically affected by the presence of volcanic ash in the air and deposited over the Argentinean territory. The first one was to create a risk management commission were this risk between others were studied, and second to develop new ground based remote sensing technologies to be able to identify and inform the risk close to the airports. In addition the Japanese government program for Science and Technology joint Research Partnership between Argentina, Chile and Japan for Sustainable Development (SATREPS) accepted to fund this cooperation due to the potential future utilization of the research outcomes to the benefit of the society. This work present the actual achievements and expected advance of these projects that try to joint efforts between national and international agencies as well as countries on behalf of a better understanding of the risks and a joint collaboration on the mitigation of suspended ashes impact over the aerial navigation.

  16. 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.

  17. Permanent Infrasound Monitoring of Active Volcanoes in Ecuador

    Science.gov (United States)

    Ruiz, M. C.; Yepes, H. A.; Steele, A.; Segovia, M.; Vaca, S.; Cordova, A.; Enriquez, W.; Vaca, M.; Ramos, C.; Arrais, S.; Tapa, I.; Mejia, F.; Macias, C.

    2013-12-01

    Since 2006, infrasound monitoring has become a permanent tool for observing, analyzing and understanding volcanic activity in Ecuador. Within the framework of a cooperative project between the Japanese International Cooperation Agency (JICA) and the Instituto Geofísico to enhance volcano monitoring capabilities within the country, 10 infrasound sensors were deployed in conjunction with broadband seismic stations at Cotopaxi and Tungurahua volcanoes. Each station comprises 1 ACO microphone (model 7144) and an amplifier with a flat response down to 0.1 Hz. At Tungurahua, between July 2006 and July 2013, the network recorded more than 5,500 explosion events with peak-to-peak pressure amplitudes larger than 45 Pa at station Mason (BMAS) which is located ~ 5.5 km from the active crater. This includes 3 explosions with pressure amplitudes larger than 1,000 Pa and which all have exhibited clear shock wave components. Two seismic and infrasound arrays were also installed in 2006 under the Acoustic Surveillance for Hazardous Eruptions (ASHE) project, used in volcano monitoring at Tungurahua, Sangay, and Reventador. This venture was led by the Geological Survey of Canada and the University of Hawaii. Through the SENESCYT-IGEPN project, the Instituto Geofísico is currently installing a regional network of MB2005 microbarometers with the aim to enhance monitoring of active and potentially active volcanoes that include Reventador, Guagua Pichincha, Chimborazo, Antisana, Sangay, and Volcán Chico in the Galapagos Islands. Through the infrasound monitoring station at Volcán Chico it is also possible to extend observations to any activity initiated from Sierra Negra, Fernandina, Cerro Azul, and Alcedo volcanoes. During the past decade, a series of temporary acoustic arrays have also been deployed around Ecuador's most active volcanoes, helping to aid in short term volcanic monitoring and/or used in a series of research projects aimed at better understanding volcanic systems

  18. Volcanic eruption source parameters from active and passive microwave sensors

    Science.gov (United States)

    Montopoli, Mario; Marzano, Frank S.; Cimini, Domenico; Mereu, Luigi

    2016-04-01

    It is well known, in the volcanology community, that precise information of the source parameters characterising an eruption are of predominant interest for the initialization of the Volcanic Transport and Dispersion Models (VTDM). Source parameters of main interest would be the top altitude of the volcanic plume, the flux of the mass ejected at the emission source, which is strictly related to the cloud top altitude, the distribution of volcanic mass concentration along the vertical column as well as the duration of the eruption and the erupted volume. Usually, the combination of a-posteriori field and numerical studies allow constraining the eruption source parameters for a given volcanic event thus making possible the forecast of ash dispersion and deposition from future volcanic eruptions. So far, remote sensors working at visible and infrared channels (cameras and radiometers) have been mainly used to detect, track and provide estimates of the concentration content and the prevailing size of the particles propagating within the ash clouds up to several thousand of kilometres far from the source as well as track back, a-posteriori, the accuracy of the VATDM outputs thus testing the initial choice made for the source parameters. Acoustic wave (infrasound) and microwave fixed scan radar (voldorad) were also used to infer source parameters. In this work we want to put our attention on the role of sensors operating at microwave wavelengths as complementary tools for the real time estimations of source parameters. Microwaves can benefit of the operability during night and day and a relatively negligible sensitivity to the presence of clouds (non precipitating weather clouds) at the cost of a limited coverage and larger spatial resolution when compared with infrared sensors. Thanks to the aforementioned advantages, the products from microwaves sensors are expected to be sensible mostly to the whole path traversed along the tephra cloud making microwaves particularly

  19. Quaternary Volcanic Activities in Shandong Peninsula and Northern Parts of Jiangsu and Anhui Provinces

    Institute of Scientific and Technical Information of China (English)

    郑洪汉; 高维明; 等

    1990-01-01

    Quaternary volcanic rocks often coexist with loess,as observed in the same geologic sections in the Shandong Peninsula and northern parts of Jiangsu and Anhui provinces.The development age of Shandong loess in close to that in the middle reaches of the Yellow River.Loess strata are of synchronous implication in the loess belt of North China.So the ages of volcanic activities can be es-timated approximately from the stratigraphic relations between loess layers and volcanic rocks.The re-sults of dating of the Quaternary volcanic rocks,baked layers and the TL dates of loess samples sug-gest that the Quaternary volcanic activity can be divided into 4 stages in the region studied,with the ages being 1.15-1.03,0.86-0.72,0.55-0.33 and 0.02 Ma B.P.respectively .The occurrence of tephra in the Shandong loess sections is possible due to multiple episodes of volcanism during the Quaternary time.

  20. Geologic evolution of the Jemez Mountains and their potential for future volcanic activity

    Energy Technology Data Exchange (ETDEWEB)

    Burton, B.W.

    1982-01-01

    Geophysical and geochemical data and the geologic history of the Rio Grande rift and the vicinity of the Jemez Mountains are summarized to determine the probability of future volcanic activity in the Los Alamos, New Mexico area. The apparent cyclic nature of volcanism in the Jemez Mountains may be related to intermittent thermal inputs into the volcanic system beneath the region. The Jemez lineament, an alignment of late Cenozoic volcanic centers that crosses the rift near Los Alamos, has played an important role in the volcanic evolution of the Jemez Mountains. Geophysical data suggest that there is no active shallow magma body beneath the Valles caldera, though magma probably exists at about 15 km beneath this portion of the rift. The rate of volcanism in the Jemez Mountains during the last 10 million years has been 5 x 10/sup -9//km/sup 2//y. Lava or ash flows overriding Laboratory radioactive waste disposal sites would have little potential to release radionuclides to the environment. The probability of a new volcano intruding close enough to a radioactive waste disposal site to effect radionuclide release is 2 x 10/sup -7//y.

  1. Monitoring and behavior of unsaturated volcanic pyroclastic in the Metropolitan Area of San Salvador, El Salvador.

    Science.gov (United States)

    Chávez, José Alexander; Landaverde, José; Landaverde, Reynaldo López; Tejnecký, Václav

    2016-01-01

    Field monitoring and laboratory results are presented for an unsaturated volcanic pyroclastic. The pyroclastic belongs to the latest plinian eruption of the Ilopango Caldera in the Metropolitan Area of San Salvador, and is constantly affected by intense erosion, collapse, slab failure, sand/silt/debris flowslide and debris avalanche during the rainy season or earthquakes. Being the flowslides more common but with smaller volume. During the research, preliminary results of rain threshold were obtained of flowslides, this was recorded with the TMS3 (a moisture sensor device using time domain transmission) installed in some slopes. TMS3 has been used before in biology, ecology and soil sciences, and for the first time was used for engineering geology in this research. This device uses electromagnetic waves to obtain moisture content of the soil and a calibration curve is necessary. With the behavior observed during this project is possible to conclude that not only climatic factors as rain quantity, temperature and evaporation are important into landslide susceptibility but also information of suction-moisture content, seepage, topography, weathering, ground deformation, vibrations, cracks, vegetation/roots and the presence of crust covering the surface are necessary to research in each site. Results of the field monitoring indicates that the presence of biological soil crusts a complex mosaic of soil, green algae, lichens, mosses, micro-fungi, cyanobacteria and other bacteria covering the slopes surface can protect somehow the steep slopes reducing the runoff process and mass wasting processes. The results obtained during the assessment will help explaining the mass wasting problems occurring in some pyroclastic soils and its possible use in mitigation works and early warning system.

  2. Volcanic eruptions observed with infrasound

    Science.gov (United States)

    Johnson, Jeffrey B.; Aster, Richard C.; Kyle, Philip R.

    2004-07-01

    Infrasonic airwaves produced by active volcanoes provide valuable insight into the eruption dynamics. Because the infrasonic pressure field may be directly associated with the flux rate of gas released at a volcanic vent, infrasound also enhances the efficacy of volcanic hazard monitoring and continuous studies of conduit processes. Here we present new results from Erebus, Fuego, and Villarrica volcanoes highlighting uses of infrasound for constraining quantitative eruption parameters, such as eruption duration, source mechanism, and explosive gas flux.

  3. Temporal changes in thermal waters related to volcanic activity of Tokachidake Volcano, Japan: implications for forecasting future eruptions

    Science.gov (United States)

    Takahashi, Ryo; Shibata, Tomo; Murayama, Yasuji; Ogino, Tagiru; Okazaki, Noritoshi

    2015-01-01

    In order to detect changes in volcanic activity of Tokachidake Volcano, Japan, we have continuously monitored thermal waters discharging at the western to southwestern flank of the volcano since 1986. The steam-heated waters in the Nukkakushi crater discharged with boiling temperature until 2002. Thermal waters at the Tokachidake spa area have similar compositions to fumarolic gas emitted from the summit craters, indicating that the waters formed by absorption of volcanic gas into shallow aquifers. Thermal waters at the Fukiage spa area were derived from the same aquifer as the Tokachidake spa area until early 1986. However, after that time, NaCl-type thermal water entered the Fukiage spa area during the increase in volcanic activity associated with the 1988-1989 eruption, thus leading to a clear increase in Cl concentrations and temperature. After the eruption, the supply of the NaCl-type thermal water was halted, and the Cl concentrations of the thermal waters decreased. In contrast, SO4 concentrations gradually increased in the Fukiage spa area after 1989, and the temperature has been maintained. These observations indicate that SO4-rich thermal water with a relatively high temperature entered the system instead of the NaCl-type thermal water. As was the case for the 1988-1989 eruption, the Cl concentrations at the Fukiage spa area increased in 2012 during an increase in volcanic activity, implying that the supply of the NaCl-type thermal water had resumed. However, the chemical changes in the thermal waters since 2012 are small compared with those before the 1988-1989 eruption, with oxygen and hydrogen isotopic compositions remaining nearly the same as those of meteoric waters.

  4. Volcanic tremor associated with eruptive activity at Bromo volcano

    Directory of Open Access Journals (Sweden)

    E. Gottschämmer

    1999-06-01

    Full Text Available Three broadband stations were deployed on Bromo volcano, Indonesia, from September to December 1995. The analysis of the seismograms shows that the signals produced by the volcanic sources cover the frequency range from at least 25 Hz down to periods of several minutes and underlines, therefore, the importance of broadband recordings. Frequency analysis reveals that the signal can be divided into four domains. In the traditional frequency range of volcanic tremor (1-10 Hz sharp transitions between two distinct values of the tremor amplitude can be observed. Additional tremor signal including frequencies from 10 to 20 Hz could be found during late November and early December. Throughout the whole experiment signals with periods of some hundred seconds were observed which are interpreted as ground tilts. For these long-period signals a particle motion analysis was performed in order to estimate the source location. Depth and radius can be estimated when the source is modeled as a sudden pressure change in a sphere. The fourth frequency range lies between 0.1 and 1 Hz and is dominated by two spectral peaks which are due to marine microseism. The phase velocity and the direction of wave propagation of these signals could be determined using the tripartite-method.

  5. Contamination monitoring activities in Kanupp

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, S.S. [Karachi Nuclear Power Plant (Pakistan)

    1997-06-01

    The Karachi Nuclear Power Plant (Kanupp) is a 137 MWe pressurized heavy water reactor, designed and erected by the Canadian General Electric Company as a turn key project. The plant is in operation since it was commissioned in the year 1972. It is located at the Arabian Sea Coast about 15 miles to the west of Karachi. During its more than two decades of operation, the plant has generated about 8 billion units of electricity with an average life time availability factor of 60%. In Kanupp, radioactive contamination may exit due to the release of fission product, activation products etc., which may somehow escape from its confinement and may contaminate surface or other media such as air, water etc. In this paper, following items are described: main aspects of contamination, status of contamination monitoring, need of contamination monitoring, radiation protection activity, instruments, contamination, current status of contamination survey materials and their disposal, and environmental monitoring. (G.K.)

  6. Active Job Monitoring in Pilots

    Science.gov (United States)

    Kuehn, Eileen; Fischer, Max; Giffels, Manuel; Jung, Christopher; Petzold, Andreas

    2015-12-01

    Recent developments in high energy physics (HEP) including multi-core jobs and multi-core pilots require data centres to gain a deep understanding of the system to monitor, design, and upgrade computing clusters. Networking is a critical component. Especially the increased usage of data federations, for example in diskless computing centres or as a fallback solution, relies on WAN connectivity and availability. The specific demands of different experiments and communities, but also the need for identification of misbehaving batch jobs, requires an active monitoring. Existing monitoring tools are not capable of measuring fine-grained information at batch job level. This complicates network-aware scheduling and optimisations. In addition, pilots add another layer of abstraction. They behave like batch systems themselves by managing and executing payloads of jobs internally. The number of real jobs being executed is unknown, as the original batch system has no access to internal information about the scheduling process inside the pilots. Therefore, the comparability of jobs and pilots for predicting run-time behaviour or network performance cannot be ensured. Hence, identifying the actual payload is important. At the GridKa Tier 1 centre a specific tool is in use that allows the monitoring of network traffic information at batch job level. This contribution presents the current monitoring approach and discusses recent efforts and importance to identify pilots and their substructures inside the batch system. It will also show how to determine monitoring data of specific jobs from identified pilots. Finally, the approach is evaluated.

  7. The Albano multiple-maar center (Rome, Italy): an active volcanic area since 70 ka

    Science.gov (United States)

    Freda, C.; Gaeta, M.; Karner, D. B.; Marra, F.; Renne, P. R.; Scarlato, P.; Taddeucci, J.

    2003-04-01

    The Albano multiple-maar center hosted the most recent activity of the Alban Hills Volcanic District. The determination of its petrochemical characteristics and its geochronology is therefore of great importance in order to evaluate the status of this volcanic area and to assess the possible volcanic hazard for Rome. Despite the detailed 40Ar/39Ar geochronologic history of the products of its activity, relatively poor information on the stratigraphy and the petrology of this volcanic center exists. In order to develop a detailed chronostratigraphy, petrology, and a more thorough knowledge of the eruptive mechanisms that characterized the recent activity of the Albano center, a joint research project is being conducted by scientists from the Istituto Nazionale di Geofisica e Vulcanologia, the University of California at Berkeley, and the Berkeley Geochronology Center. Here we have studied the most complete stratigraphic section located within the northern crater rim of Albano, where most of the products are exposed. We have investigated proximal and distal outcrops, in order to correlate them to the units identified in the northern crater rim section. We will present our recently acquired geochronologic and petrochemical data, which indicates magma chamber recharge associated with this <70 ka volcanism.

  8. Characterization of the Etna volcanic emissions through an active biomonitoring technique (moss-bags): part 1--major and trace element composition.

    Science.gov (United States)

    Calabrese, S; D'Alessandro, W; Bellomo, S; Brusca, L; Martin, R S; Saiano, F; Parello, F

    2015-01-01

    Active biomonitoring using moss-bags was applied to an active volcanic environment for the first time. Bioaccumulation originating from atmospheric deposition was evaluated by exposing mixtures of washed and air-dried mosses (Sphagnum species) at 24 sites on Mt. Etna volcano (Italy). Concentrations of major and a large suite of trace elements were analysed by inductively coupled mass and optical spectrometry (ICP-MS and ICP-OES) after total acid digestion. Of the 49 elements analysed those which closely reflect summit volcanic emissions were S, Tl, Bi, Se, Cd, As, Cu, B, Na, Fe, Al. Enrichment factors and cluster analysis allowed clear distinction between volcanogenic, geogenic and anthropogenic inputs that affect the local atmospheric deposition. This study demonstrates that active biomonitoring with moss-bags is a suitable and robust technique for implementing inexpensive monitoring in scarcely accessible and harsh volcanic environments, giving time-averaged quantitative results of the local exposure to volcanic emissions. This task is especially important in the study area because the summit area of Mt. Etna is visited by nearly one hundred thousand tourists each year who are exposed to potentially harmful volcanic emissions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Volcanic and Tectonic Activity in the Red Sea Region (2004-2013): Insights from Satellite Radar Interferometry and Optical Imagery

    KAUST Repository

    Xu, Wenbin

    2015-04-01

    Studying recent volcanic and tectonic events in the Red Sea region is important for improving our knowledge of the Red Sea plate boundary and for regional geohazard assessments. However, limited information has been available about the past activity due to insufficient in-situ data and remoteness of some of the activity. In this dissertation, I have used satellite remote sensing to derive new information about several recent volcanic and tectonic events in the Red Sea region. I first report on three volcanic eruptions in the southern Red Sea, the 2007-8 Jebel at Tair eruption and the 2011-12 & 2013 Zubair eruptions, which resulted in formation of two new islands. Series of high- resolution optical images were used to map the extent of lava flows and to observe and analyze the growth and destructive processes of the new islands. I used Interferometric Synthetic Aperture Radar (InSAR) data to study the evolution of lava flows, to estimate their volumes, as well as to generate ground displacements maps, which were used to model the dikes that fed the eruptions. I then report on my work of the 2009 Harrat Lunayyir dike intrusion and the 2004 Tabuk earthquake sequence in western Saudi Arabia. I used InSAR observations and stress calculations to study the intruding dike at Harrat Lunayyir, while I combined InSAR data and Bayesian estimation to study the Tabuk earthquake activity. The key findings of the thesis are: 1) The recent volcanic eruptions in the southern Red Sea indicate that the area is magmatically more active than previously acknowledged and that a rifting episode has been taken place in the southern Red Sea; 2) Stress interactions between an ascending dike intrusion and normal faulting on graben-bounding faults above the dike can inhibit vertical propagation of magma towards the surface; 3) InSAR observations can improve locations of shallow earthquakes and fault model uncertainties are useful to associate earthquake activity with mapped faults; 4). The

  10. 2013 volcanic activity in Alaska: summary of events and response of the Alaska Volcano Observatory

    Science.gov (United States)

    Dixon, James P.; Cameron, Cheryl; McGimsey, Robert G.; Neal, Christina A.; Waythomas, Chris

    2015-08-14

    The Alaska Volcano Observatory (AVO) responded to eruptions, volcanic unrest or suspected unrest, and seismic events at 18 volcanic centers in Alaska during 2013. Beginning with the 2013 AVO Summary of Events, the annual description of the AVO seismograph network and activity, once a stand-alone publication, is now part of this report. Because of this change, the annual summary now contains an expanded description of seismic activity at Alaskan volcanoes. Eruptions occurred at three volcanic centers in 2013: Pavlof Volcano in May and June, Mount Veniaminof Volcano in June through December, and Cleveland Volcano throughout the year. None of these three eruptive events resulted in 24-hour staffing at AVO facilities in Anchorage or Fairbanks.

  11. δ18O and δD variations in some volcanic lakes on the Cameroon Volcanic Line (West-Africa: generating isotopic baseline data for volcano monitoring and surveillance in Cameroon

    Directory of Open Access Journals (Sweden)

    . Issa

    2014-06-01

    Full Text Available Based on geo-anthropological and geochemical studies, catastrophes similar to the unprecedented gas explosions in the mid-1980s from the Cameroonian killer lakes Nyos and Monoun, might occur in any of the 37 other lakes located along the Cameroon Volcanic Line (CVL. Because people could suffer loss and desolation from predictable catastrophes in the future, monitoring/surveillance policies must be established. Due to their location, crater lakes integrate the geochemical processes that develop in the Earth’s crust due to magmatic activities. Therefore, monitoring the surface manifestations of those deep seated and/or hydrothermal processes might reveal increases/decreases in magmatic activities. The anomalous changes in a volcanic lake induced by mixing with exogenous fluids that have a specific δ18O and δD compositional fingerprint (magmatic, metamorphic, etc. could be utilized to predict volcanic hazards. If the steady state of a lake environment and the external and intrinsic parameters that control its hydrodynamics are clearly identified and reasonably understood, the anomalous evolutionary processes that compromise its stability can be identified. This study attempts to collect the δ18O and δD data from 17 Cameroonian lakes to help establish a volcano-related monitoring/surveillance network. This work identifies the processes that control the isotopic composition of the lakes and assesses the intra-/inter- and spatial δ18O/δD variations. Almost all of the lakes contain meteoric water. These lakes are mostly isotopically stratified; epilimnia is generally more positive than the hypolimnia. However, although the rainfall is gradually depleted in heavy isotopes when moving from the South to the North due to the latitude effect, the lakes become more enriched (0.6‰/100 km due to evaporation. The evaluated impact of several parameters on the isotopic variation suggests that the hydrological setting may play an important, albeit not

  12. Monitoring eruption activity using temporal stress changes at Mount Ontake volcano

    Science.gov (United States)

    Terakawa, Toshiko; Kato, Aitaro; Yamanaka, Yoshiko; Maeda, Yuta; Horikawa, Shinichiro; Matsuhiro, Kenjiro; Okuda, Takashi

    2016-01-01

    Volcanic activity is often accompanied by many small earthquakes. Earthquake focal mechanisms represent the fault orientation and slip direction, which are influenced by the stress field. Focal mechanisms of volcano-tectonic earthquakes provide information on the state of volcanoes via stresses. Here we demonstrate that quantitative evaluation of temporal stress changes beneath Mt. Ontake, Japan, using the misfit angles of focal mechanism solutions to the regional stress field, is effective for eruption monitoring. The moving average of misfit angles indicates that during the precursory period the local stress field beneath Mt. Ontake was deviated from the regional stress field, presumably by stress perturbations caused by the inflation of magmatic/hydrothermal fluids, which was removed immediately after the expulsion of volcanic ejecta. The deviation of the local stress field can be an indicator of increases in volcanic activity. The proposed method may contribute to the mitigation of volcanic hazards. PMID:26892716

  13. Monitoring eruption activity using temporal stress changes at Mount Ontake volcano.

    Science.gov (United States)

    Terakawa, Toshiko; Kato, Aitaro; Yamanaka, Yoshiko; Maeda, Yuta; Horikawa, Shinichiro; Matsuhiro, Kenjiro; Okuda, Takashi

    2016-02-19

    Volcanic activity is often accompanied by many small earthquakes. Earthquake focal mechanisms represent the fault orientation and slip direction, which are influenced by the stress field. Focal mechanisms of volcano-tectonic earthquakes provide information on the state of volcanoes via stresses. Here we demonstrate that quantitative evaluation of temporal stress changes beneath Mt. Ontake, Japan, using the misfit angles of focal mechanism solutions to the regional stress field, is effective for eruption monitoring. The moving average of misfit angles indicates that during the precursory period the local stress field beneath Mt. Ontake was deviated from the regional stress field, presumably by stress perturbations caused by the inflation of magmatic/hydrothermal fluids, which was removed immediately after the expulsion of volcanic ejecta. The deviation of the local stress field can be an indicator of increases in volcanic activity. The proposed method may contribute to the mitigation of volcanic hazards.

  14. Science at the policy interface: volcano-monitoring technologies and volcanic hazard management

    Science.gov (United States)

    Donovan, Amy; Oppenheimer, Clive; Bravo, Michael

    2012-07-01

    This paper discusses results from a survey of volcanologists carried out on the Volcano Listserv during late 2008 and early 2009. In particular, it examines the status of volcano monitoring technologies and their relative perceived value at persistently and potentially active volcanoes. It also examines the role of different types of knowledge in hazard assessment on active volcanoes, as reported by scientists engaged in this area, and interviewees with experience from the current eruption on Montserrat. Conclusions are drawn about the current state of monitoring and the likely future research directions, and also about the roles of expertise and experience in risk assessment on active volcanoes; while local knowledge is important, it must be balanced with fresh ideas and expertise in a combination of disciplines to produce an advisory context that is conducive to high-level scientific discussion.

  15. Improvements on Near Real Time Detection of Volcanic Ash Emissions for Emergency Monitoring with Limited Satellite Bands

    Directory of Open Access Journals (Sweden)

    Torge Steensen

    2015-03-01

    Full Text Available Quantifying volcanic ash emissions syneruptively is an important task for the global aviation community. However, due to the near real time nature of volcano monitoring, many parameters important for accurate ash mass estimates cannot be obtained easily. Even when using the best possible estimates of those parameters, uncertainties associated with the ash masses remain high, especially if the satellite data is only available in the traditional 10.8 and 12.0 μm bands. To counteract this limitation, we developed a quantitative comparison between the ash extents in satellite and model data. The focus is the manual cloud edge definition based on the available satellite reverse absorption (RA data as well as other knowledge like pilot reports or ground-based observations followed by an application of the Volcanic Ash Retrieval on the defined subset with an RA threshold of 0 K. This manual aspect, although subjective to the experience of the observer, can show a significant improvement as it provides the ability to highlight ash that otherwise would be obscured by meteorological clouds or, by passing over different surfaces with unaccounted temperatures, might be lost entirely and thus remains undetectable for an automated satellite approach. We show comparisons to Volcanic Ash Transport and Dispersion models and outline a quantitative match as well as percentages of overestimates based on satellite or dispersion model data which can be converted into a level of reliability for near real time volcano monitoring

  16. Water-quality effects on Baker Lake of recent volcanic activity at Mount Baker, Washington

    Science.gov (United States)

    Bortleson, Gilbert Carl; Wilson, Reed T.; Foxworthy, B.L.

    1976-01-01

    , mineral-rich inflow depend mainly on: (1) the rate of flow and the character of Boulder Creek water at the time; (2) the relative rate of inflow of the feedwater from other streams; and (3) whether the reservoir is temperature-stratified (summer) or homothermal (winter). A distinct layer of Boulder Creek water was found in the lake in September 1975 extending at least 0.3 miles (.5 km) downreservoir. The greatest opportunity for water from Boulder Creek to persist as a layer and extend farthest before mixing with the other reservoir water is when Baker Lake is strongly stratified and Boulder Creek flow rate is large in relation to other feedwater. Baker Lake probably could assimilate indefinitely the acid loads measured during 1975, by dilution, chemical neutralization, and buffering of the acid-rich Boulder creek water. Minor elements found in Boulder Creek water included arsenic, selenium, and mercury; however, none of these would reach the limits recommended by the U.S. Environmental Protection Agency for public water supplies unless their concentrations increased to several times the amounts found during this study. Under the prevailing conditions, acid-rich Boulder Creek water apparently cannot accumulate as a pool, or persist as a layer long enough to reach Upper Baker Dam and attack the concrete. However, even if the acid load from Boulder Creek does not greatly increase, occasional light fish mortalities may result near the mouth of the creek. Greater acid and mineral loads, resulting from further increases in volcanic activity or other possible causes, could be more harmful, especially to the fish. Continued monitoring of Boulder Creek flow and water quality is needed to rapidly any changes in conditions at Sherman Crater, and to provide warning of possible greater impacts on Baker Lake from any future increases in Mount Baker activity.

  17. Elemental characterization of Mt. Sinabung volcanic ash, Indonesia by Neutron Activation Analysis

    Science.gov (United States)

    Kusmartini, I.; Syahfitri, W. Y. N.; Kurniawati, S.; Lestiani, D. D.; Santoso, M.

    2017-06-01

    Mount Sinabung is a volcano located in North Sumatera, Indonesia which has been recorded not erupted since 1600. However in 2013 it has been erupted and cause of black thick smog, rain sand and volcanic ash. Volcanic ash containing trace elements material that can be utilized in various applications but still has potential danger of heavy metals. In order to obtain an elemental composition data of volcanic ash, the characterization of volcanic ash were carried out using Neutron Activation Analysis. The volcanic ash was taken from Mt. Sinabung eruption. Samples were irradiated at the rabbit system in the reactor G.A Siwabessy facilities with neutron flux ˜ 1013 n.cm-2.s-1 and then counted using HPGe detector. Method validation was carried out by SRM NIST Coal Fly Ash 1633b and NIST 2711a Montana II Soil with recovery values were in the range of 96-108% and 95-106% respectively. The results showed that major elements; Al, Na, Ca and Fe, concentrations were 8.7, 1.05, 2.98 and 7.44 %, respectively, minor elements K, Mg, Mn, Ti, V and Zn were 0.87%, 0.78%, 0.18%, 0.62%, 197.13 ppm and 109.35 ppm, respectively, heavy metals; As, Cr, Co and Sb, contents were 4.48, 11.75, 17.13 and 0.35 ppm, respectively while rare earth elements such as Ce, Eu, La, Nd, Sm, Yb were 45.33, 1.22, 19.63, 20.34, 3.86, and 2.57 ppm respectively. The results of the elemental contents of volcanic ash that has been obtained can be used as the scientific based data for volcanic material utilization by considering the economic potential of elements contained and also the danger of the heavy metals content.

  18. High speed imaging, lightning mapping arrays and thermal imaging: a synergy for the monitoring of electrical discharges at the onset of volcanic explosions

    Science.gov (United States)

    Gaudin, Damien; Cimarelli, Corrado; Behnke, Sonja; Cigala, Valeria; Edens, Harald; McNutt, Stefen; Smith, Cassandra; Thomas, Ronald; Van Eaton, Alexa

    2017-04-01

    Volcanic lightning is being increasingly studied, due to its great potential for the detection and monitoring of ash plumes. Indeed, it is observed in a large number of ash-rich volcanic eruptions and it produces electromagnetic waves that can be detected remotely in all weather conditions. Electrical discharges in volcanic plume can also significantly change the structural, chemical and reactivity properties of the erupted material. Although electrical discharges are detected in various regions of the plume, those happening at the onset of an explosion are of particular relevance for the early warning and the study of volcanic jet dynamics. In order to better constrain the electrical activity of young volcanic plumes, we deployed at Sakurajima (Japan) in 2015 a multiparametric set-up including: i) a lightning mapping array (LMA) of 10 VHF antennas recording the electromagnetic waves produced by lightning at a sample rate of 25 Msps; ii) a visible-light high speed camera (5000 frames per second, 0.5 m pixel size, 300 m field of view) shooting short movies (approx. duration 1 s) at different stages of the plume evolution, showing the location of discharges in relation to the plume; and iii) a thermal camera (25 fps, 1.5 m pixel size, 800 m field of view) continuously recording the plume and allowing the estimation of its main source parameters (volume, rise velocity, mass eruption rate). The complementarity of these three setups is demonstrated by comparing and aggregating the data at various stages of the plume development. In the earliest stages, the high speed camera spots discrete small discharges, that appear on the LMA data as peaks superimposed to the continuous radio frequency (CRF) signal. At later stages, flashes happen less frequently and increase in length. The correspondence between high speed camera and LMA data allows to define a direct correlation between the length of the flash and the intensity of the electromagnetic signal. Such correlation is

  19. Volcanic gas composition changes during the gradual decrease of the gigantic degassing activity of Miyakejima volcano, Japan, 2000-2015

    Science.gov (United States)

    Shinohara, Hiroshi; Geshi, Nobuo; Matsushima, Nobuo; Saito, Genji; Kazahaya, Ryunosuke

    2017-02-01

    The composition of volcanic gases discharged from Miyakejima volcano has been monitored during the intensive degassing activity that began after the eruption in 2000. During the 15 years from 2000 to 2015, Miyakejima volcano discharged 25.5 Mt of SO2, which required degassing of 3 km3 of basaltic magma. The SO2 emission rate peaked at 50 kt/day at the end of 2000 and quickly decreased to 5 kt/day by 2003. During the early degassing period, the volcanic gas composition was constant with the CO2/SO2 = 0.8 (mol ratio), H2O/SO2 = 35, HCl/SO2 = 0.08, and SO2/H2S = 15. The SO2 emission rate decreased gradually to 0.5 kt/day by 2012, and the gas composition also changed gradually to CO2/SO2 = 1.5, H2O/SO2 = 150, HCl/SO2 = 0.15, and SO2/H2S = 6. The compositional changes are not likely caused by changes in degassing pressure or volatile heterogeneity of a magma chamber but are likely attributed to an increase of hydrothermal scrubbing caused by large decrease of the volcanic gas emission rate, suggesting a supply of gases with constant composition during the 15 years. The intensive degassing was modeled based on degassing of a convecting magma conduit. The gradual SO2 emission rate that decrease without changes in volcanic gas composition is attributed to a reduction of diameter of the convecting magma conduit.

  20. Link of volcanic activity and climate change in Altai studied in the ice core from Belukha Mountain

    OpenAIRE

    N. S. Malygina; T. V. Barlyaeva; T. S. Papina

    2013-01-01

    In the present research we discuss a role of volcanic activity in Altai thermal regime. Here we analyses the sulfate and temperature data reconstructed from the natural paleoarchive – ice core from the Belukha Mountain saddle. Sulfate ice-core reconstructions can serve as volcanic markers. The both – sulfate and temperature reconstructions – are for the last 750 years. As the characteristic of volcanic activity we consider Volcanic Explosivity Index (VEI), Dust Veil Index (DVI) and Ice core v...

  1. The influence of volcanic activity on suspended sediment yield of rivers (Kamchatka, Russia)

    Science.gov (United States)

    Kuksina, Ludmila

    2014-05-01

    Kamchatka is specific region of suspended sediment yield formation. This fact is particularly connected with active volcanism in the territory. The influence of volcanism on suspended sediment yield characteristics was studied in various time scales - into-diurnal, seasonal and long-term ones. The study of spatial variability of these characteristics reveals the maximum values characterize river basins in zones of strong impact of volcanic eruptions, especially, rivers draining slopes and flanks of active volcanoes. Into-diurnal fluctuations were studied for rivers in volcanic areas. They are characterized by synchronous changes of water flow and turbidity. It's determined by weak erosion-preventive capacity of friable volcanic deposits and big slopes of channels (2.5 - 6.0 %). The maximum of water flow and turbidity is observed at the period between 12 and 6 pm. The air temperature reaches its maximum by that time, and consequently, the intensity of snow melting is also maximum one. The maximum of turbidity advances diurnal maximum of water flow a little, and it's connected with the features of flood wave moving and consecutive maximums of slopes, turbidity, velocity, water flow, and capacity of stream during flush. Into-diurnal fluctuations are determined by complicated and little-studied processes of mass transfer between stream and channel deposits. These processes are connected with into-diurnal changes of stream capacity and water transfer between channel and underflow. As the result water regime is pulsating. Rivers under the influence of volcanic eruptions transport the main amount of sediments during floods which usually occur in summer-autumn period (in the absence of extreme floods in winter-spring period during volcanic eruptions). Combination of maximum snow supply, significant precipitation in warm part of the year and weak erosion-preventive capacity of friable volcanic deposits on volcanoes slopes is the reason of the most intense erosion in this

  2. 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.

  3. Search for possible relationship between volcanic ash particles and thunderstorm lightning activity

    Science.gov (United States)

    Várai, A.; Vincze, M.; Lichtenberger, J.; Jánosi, I. M.

    2011-12-01

    Explosive volcanic eruptions that eject columns of ash from the crater often generate lightning discharges strong enough to be remotely located by very low frequency radio waves. A fraction of volcanic ash particles can stay and disperse long enough to have an effect on weather phenomena days later such as thunderstorms and lightnings. In this work we report on lightning activity analysis over Europe following two recent series of volcanic eruptions in order to identify possible correlations between ash release and subsequent thunderstorm flash frequency. Our attempts gave negative results which can be related to the fact that we have limited information on local atmospheric variables of high enough resolution, however lightning frequency is apparently determined by very local circumstances.

  4. Multiple episodes of hydrothermal activity and epithermal mineralization in the southwestern Nevada volcanic field and their relations to magmatic activity, volcanism and regional extension

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, S.I.; Noble, D.C.; Jackson, M.C. [Univ. of Nevada, Reno, NV (United States)] [and others

    1994-12-31

    Volcanic rocks of middle Miocene age and underlying pre-Mesozoic sedimentary rocks host widely distributed zones of hydrothermal alteration and epithermal precious metal, fluorite and mercury deposits within and peripheral to major volcanic and intrusive centers of the southwestern Nevada volcanic field (SWNVF) in southern Nevada, near the southwestern margin of the Great Basin of the western United States. Radiometric ages indicate that episodes of hydrothermal activity mainly coincided with and closely followed major magmatic pulses during the development of the field and together spanned more than 4.5 m.y. Rocks of the SWNVF consist largely of rhyolitic ash-flow sheets and intercalated silicic lava domes, flows and near-vent pyroclastic deposits erupted between 15.2 and 10 Ma from vent areas in the vicinity of the Timber Mountain calderas, and between about 9.5 and 7 Ma from the outlying Black Mountain and Stonewall Mountain centers. Three magmatic stages can be recognized: the main magmatic stage, Mountain magmatic stage (11.7 to 10.0 Ma), and the late magmatic stage (9.4 to 7.5 Ma).

  5. Soil radon measurements as a potential tracer of tectonic and volcanic activity

    Science.gov (United States)

    Neri, Marco; Ferrera, Elisabetta; Giammanco, Salvatore; Currenti, Gilda; Cirrincione, Rosolino; Patanè, Giuseppe; Zanon, Vittorio

    2016-04-01

    In Earth Sciences there is a growing interest in studies concerning soil-radon activity, due to its potential as a tracer of numerous natural phenomena. Our work marks an advance in the comprehension of the interplay between tectonic activity, volcanic eruptions and gas release through faults. Soil-radon measurements, acquired on Mt. Etna volcano in 2009–2011, were analyzed. Our radon probe is sensitive to changes in both volcanic and seismic activity. Radon data were reviewed in light of the meteorological parameters. Soil samples were analyzed to characterize their uranium content. All data have been summarized in a physical model which identifies the radon sources, highlights the mechanism of radon transport and envisages how such a mechanism may change as a consequence of seismicity and volcanic events. In the NE of Etna, radon is released mainly from a depth of 50 m/day. Three periods of anomalous gas release were found (February 2010, January and February 2011). The trigger of the first anomaly was tectonic, while the second and third had a volcanic origin. These results mark a significant step towards a better understanding of the endogenous mechanisms that cause changes in soil-radon emission at active volcanoes.

  6. Soil radon measurements as a potential tracer of tectonic and volcanic activity.

    Science.gov (United States)

    Neri, Marco; Ferrera, Elisabetta; Giammanco, Salvatore; Currenti, Gilda; Cirrincione, Rosolino; Patanè, Giuseppe; Zanon, Vittorio

    2016-04-15

    In Earth Sciences there is a growing interest in studies concerning soil-radon activity, due to its potential as a tracer of numerous natural phenomena. Our work marks an advance in the comprehension of the interplay between tectonic activity, volcanic eruptions and gas release through faults. Soil-radon measurements, acquired on Mt. Etna volcano in 2009-2011, were analyzed. Our radon probe is sensitive to changes in both volcanic and seismic activity. Radon data were reviewed in light of the meteorological parameters. Soil samples were analyzed to characterize their uranium content. All data have been summarized in a physical model which identifies the radon sources, highlights the mechanism of radon transport and envisages how such a mechanism may change as a consequence of seismicity and volcanic events. In the NE of Etna, radon is released mainly from a depth of 50 m/day. Three periods of anomalous gas release were found (February 2010, January and February 2011). The trigger of the first anomaly was tectonic, while the second and third had a volcanic origin. These results mark a significant step towards a better understanding of the endogenous mechanisms that cause changes in soil-radon emission at active volcanoes.

  7. Mount Kenya volcanic activity and the Late Cenozoic landscape reorganisation in the upper Tana fluvial system

    NARCIS (Netherlands)

    Veldkamp, A.; Schoorl, J.M.; Wijbrans, J.R.; Claessens, L.F.G.

    2012-01-01

    Volcanic–fluvial landscape interaction of the late Cenozoic Mt Kenya region in the upper Tana catchment has been reconstructed. The oldest newly dated phonolite flow is 5.78 Ma (40Ar/39Ar), placing the initiation of Mt Kenya volcanic activity within the Late Miocene, much earlier than reported befor

  8. Late Pleistocene and Holocene activity of the Atacazo-Ninahuilca Volcanic Complex (Ecuador)

    NARCIS (Netherlands)

    Hidalgo, Silvana; Monzier, Michel; Almeida, Eduardo; Chazot, Gilles; Eissen, Jean-Philippe; van der Plicht, Johannes; Hall, Minard L.

    2008-01-01

    The Atacazo-Ninahuilca Volcanic Complex (ANVC) is located in the Western Cordillera of Ecuador, 10 km southwest of Quito. At least six periods of Pleistocene to Holocene activity (N1 to N6) have been preserved in the geologic record as tephra fallouts and pyroclastic flow deposits. New field data,

  9. Significance of an Active Volcanic Front in the Far Western Aleutian Arc

    Science.gov (United States)

    Yogodzinski, G. M.; Kelemen, P. B.; Hoernle, K.

    2015-12-01

    Discovery of a volcanic front west of Buldir Volcano, the western-most emergent Aleutian volcano, demonstrates that the surface expression of Aleutian volcanism falls below sea level just west of 175.9° E longitude, but is otherwise continuous from mainland Alaska to Kamchatka. The newly discovered sites of western Aleutian seafloor volcanism are the Ingenstrem Depression, a 60 km-long structural depression just west of Buldir, and an unnamed area 300 km further west, referred to as the Western Cones. These locations fall along a volcanic front that stretches from Buldir to Piip Seamount near the Komandorsky Islands. Western Aleutian seafloor volcanic rocks include large quantities of high-silica andesite and dacite, which define a highly calc-alkaline igneous series and carry trace element signatures that are unmistakably subduction-related. This indicates that subducting oceanic lithosphere is present beneath the westernmost Aleutian arc. The rarity of earthquakes below depths of 200 km indicates that the subducting plate is unusually hot. Some seafloor volcanoes are 6-8 km wide at the base, and so are as large as many emergent Aleutian volcanoes. The seafloor volcanoes are submerged in water depths >3000 m because they sit on oceanic lithosphere of the Bering Sea. The volcanic front is thus displaced to the north of the ridge of arc crust that underlies the western Aleutian Islands. This displacement, which developed since approximately 6 Ma when volcanism was last active on the islands, must be a consequence of oblique convergence in a system where the subducting plate and large blocks of arc crust are both moving primarily in an arc-parallel sense. The result is a hot-slab system where low subduction rates probably limit advection of hot mantle to the subarc, and produce a relatively cool and perhaps stagnant mantle wedge. The oceanic setting and highly oblique subduction geometry also severely limit rates of sediment subduction, so the volcanic rocks, which

  10. Characterization of the Etna volcanic emissions through an active biomonitoring technique (moss-bags): part 2--morphological and mineralogical features.

    Science.gov (United States)

    Calabrese, S; D'Alessandro, W

    2015-01-01

    Volcanic emissions were studied at Mount Etna (Italy) by using moss-bags technique. Mosses were exposed around the volcano at different distances from the active vents to evaluate the impact of volcanic emissions in the atmosphere. Morphology and mineralogy of volcanic particulate intercepted by mosses were investigated using scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS). Particles emitted during passive degassing activity from the two active vents, Bocca Nuova and North East Crater (BNC and NEC), were identified as silicates, sulfates and halide compounds. In addition to volcanic particles, we found evidences also of geogenic, anthropogenic and marine spray input. The study has shown the robustness of this active biomonitoring technique to collect particles, very useful in active volcanic areas characterized by continuous degassing and often not easily accessible to apply conventional sampling techniques.

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

    Science.gov (United States)

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

    2015-12-01

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

  12. Poás volcano: Relationships between diffuse vs active CO degassing and long term volcanic activity.

    Science.gov (United States)

    Epiard, Matthieu; Avard, Geoffroy; de Moor, Marteen; Martinez Cruz, Maria; Bakkar, Henriette

    2017-04-01

    Active volcanoes exhibit diffuse gas emanations through the ground. Carbon dioxide is one of the most abundant species, in addition to the gases actively released through channelized vents. CO₂ diffuse degassing is not always correlated to volcanic activity but CO₂ diffuse vs active degassing ratios appears to show interesting behavior regarding fluctuations in volcanic activity. CO₂ diffuse degassing data were obtained at Poás volcano (Costa Rica) in 2011 using the accumulation chamber method with the aim of estimating the total diffuse CO₂ budget. This result was compared to active degassing data, as well as to previous CO₂ diffuse degassing data measured between 2000 and 2004, when Poás entered in a stage of enhanced volcanic activity. Results show a dramatic decrease in CO₂ diffuse degassing rate between 2000 and 2011 of more than 500t/d, following an increasing trend in total gas emission and power output between September 1995 and the end of 2001. Thus, the ratio of diffuse to active degassing has dramatically decreased with the increase of volcanic activity and occurrence of phreatic eruption. Two main hypothesis could explain those results: 1) Either the rising of magma to shallower levels allows the gas to be better channelized due to enhanced permeability and conduit opening, or 2) Poás volcano might experience a periodic pattern of hydrothermal sealing/overpressure/eruption that allows the system to shift from a regimen of passive degassing to active degassing.

  13. Volcanic hazards to airports

    Science.gov (United States)

    Guffanti, M.; Mayberry, G.C.; Casadevall, T.J.; Wunderman, R.

    2009-01-01

    , Tungurahua in Ecuador, Mt. Etna in Italy, Rabaul caldera in Papua New Guinea, Mt. Spurr and Mt. St. Helens in the USA, Ruapehu in New Zealand, Mt. Pinatubo in the Philippines, and Anatahan in the Commonwealth of the Northern Mariana Islands (part of the USA). Ten countries - USA, Indonesia, Ecuador, Papua New Guinea, Italy, New Zealand, Philippines, Mexico, Japan, and United Kingdom - have the highest volcanic hazard and/or vulnerability measures for airports. The adverse impacts of volcanic eruptions on airports can be mitigated by preparedness and forewarning. Methods that have been used to forewarn airports of volcanic activity include real-time detection of explosive volcanic activity, forecasts of ash dispersion and deposition, and detection of approaching ash clouds using ground-based Doppler radar. Given the demonstrated vulnerability of airports to disruption from volcanic activity, at-risk airports should develop operational plans for ashfall events, and volcano-monitoring agencies should provide timely forewarning of imminent volcanic-ash hazards directly to airport operators. ?? Springer Science+Business Media B.V. 2008.

  14. Toward a pro-active scientific advice on global volcanic activity within the multi-hazard framework of the EU Aristotle project

    Science.gov (United States)

    Barsotti, Sara; Duncan, Melanie; Loughlin, Susan; Gísladóttir, Bryndis; Roberts, Matthew; Karlsdóttir, Sigrún; Scollo, Simona; Salerno, Giuseppe; Corsaro, Rosa Anna; Charalampakis, Marinos; Papadopoulos, Gerassimos

    2017-04-01

    The demand for timely analysis and advice on global volcanic activity from scientists is growing. At the same time, decision-makers require more than an understanding of hazards; they need to know what impacts to expect from ongoing and future events. ARISTOTLE (All Risk Integrated System TOwards Trans-boundary hoListic Early-warning) is a two-year EC funded pilot project designed to do just that. The Emergency Response Coordination Centre (ERCC) works to support and coordinate response to disasters both inside and outside Europe using resources from the countries participating in the European Union Civil Protection Mechanism. Led by INGV and ZAMG, the ARISTOTLE consortium comprises 15 institutions across Europe and aims to deliver multi-hazard advice on natural events, including their potential interactions and impact, both inside and outside of Europe to the ERCC. Where possible, the ERCC would like a pro-active provision of scientific advice by the scientific group. Iceland Met Office leads the volcanic hazards work, with BGS, INGV and NOA comprising the volcano observatory team. At this stage, the volcanology component of the project comprises mainly volcanic ash and gas dispersal and potential impact on population and ground-based critical infrastructures. We approach it by relying upon available and official volcano monitoring institutions' reporting of activity, existing assessments and global databases of past events, modelling tools, remote-sensing observational systems and official VAAC advisories. We also make use of global assessments of volcanic hazards, country profiles, exposure and proxy indicators of threat to livelihoods, infrastructure and economic assets (e.g. Global Volcano Model outputs). Volcanic ash fall remains the only hazard modelled at the global scale. Volcanic risk assessments remain in their infancy, owing to challenges related to the multitude of hazards, data availability and model representation. We therefore face a number of

  15. The influence of volcanic activity in the Campi Flegrei coastal depositional system

    Science.gov (United States)

    Violante, Crescenzo; Esposito, Eliana; Molisso, Flavia; Porfido, Sabina; Sacchi, Marco

    2010-05-01

    The Campi Flegrei coastal area includes the bay of Pozzuoli, Procida and Ischia islands, characterized by active tectonics and volcanism since the Pleistocene. Numerous monogenic volcanoes occur close to the shoreline and volcanic debris interpreted as submarine counterpart of subaerial flows and surges, have been detected offshore. In the Pozzuoli area the most recent eruptive volcanic activity occurred from 10.0 to 8.0 ky B.P and 4.5 to 3.7 ky B.P. followed by the September 1538 Monte Nuovo eruption. Here magma-related activity is testified by extensive hydrothermalism, and recent episodes (1970-71 and 1982-84 on Pozzuoli coast) of shallow seismicity and ground deformation, exceeding rates of 100 cm/year in the years 1983-1984. The most recent volcanic activity on Ischia island starts around 10.0 ky B.P. to which associates several eruptive centres mostly located in the western sector. The last eruption dates back to Arso flow in 1302. Nevertheless the landscape of Ischia is dominated by Mount Epomeo in the central part of the island, which is the highest peak (788 m). It is a volcano-tectonic structure that raised above sea level between 33 and 28 ka BP, due to the intrusion of magma at shallow depth. Procida island is composed of five monogenic Volcanoes (Vivara, Terra Murata, Pozzo Vecchio, Fiumicello and Solchiaro) that have been active over the last 80 ky producing pyroclastic deposits and a lava dome. A sixth volcanic structure has been reported recently off P.ta Serra by marine investigations and confirmed by airborne magnetic surveys. The emplacement of large amount of volcanoclastic material from volcanic and volcano-tectonic activity in the Campi Flegrei coastal area produced extensive avalanche deposits off Ischia island, seafloor instabilities in the form of creep/slump, channelled sediment flow and deep sedimentary fans, and is largely responsible for aggradation/progradation of the coastal area during the Quaternary. Moreover, numerous volcanic bank

  16. Assessing the Altitude and Dispersion of Volcanic Plumes Using MISR Multi-angle Imaging from Space: Sixteen Years of Volcanic Activity in the Kamchatka Peninsula, Russia

    Science.gov (United States)

    Flower, Verity J. B.; Kahn, Ralph A.

    2017-01-01

    Volcanic eruptions represent a significant source of atmospheric aerosols and can display local, regional and global effects, impacting earth systems and human populations. In order to assess the relative impacts of these events, accurate plume injection altitude measurements are needed. In this work, volcanic plumes generated from seven Kamchatka Peninsula volcanoes (Shiveluch, Kliuchevskoi, Bezymianny, Tolbachik, Kizimen, Karymsky and Zhupanovsky), were identified using over 16 years of Multi-angle Imaging SpectroRadimeter (MISR) measurements. Eighty-eight volcanic plumes were observed by MISR, capturing 3-25% of reported events at individual volcanoes. Retrievals were most successful where high intensity events persisted over a period of weeks to months. Compared with existing ground and airborne observations, and alternative satellite-based reports compiled by the Global Volcanism Program (GVP), MISR plume height retrievals showed general consistency; the comparison reports appear to be skewed towards the region of highest concentration observed in MISR-constrained vertical plume extent. The report observations display less discrepancy with MISR toward the end of the analysis period, with improvements in the suborbital data likely the result of the deployment of new instrumentation. Conversely, the general consistency of MISR plume heights with conventionally reported observations supports the use of MISR in the ongoing assessment of volcanic activity globally, especially where other types of volcanic plume observations are unavailable. Differences between the northern (Shiveluch, Kliuchevskoi, Bezymianny and Tolbachik) and southern (Kizimen, Karymsky and Zhupanovsky) volcanoes broadly correspond to the Central Kamchatka Depression (CKD) and Eastern Volcanic Front (EVF), respectively, geological sub-regions of Kamchatka distinguished by varying magma composition. For example, by comparison with reanalysis-model simulations of local meteorological conditions

  17. Exploratory Data Analysis Using a Dedicated Visualization App: Looking for Patterns in Volcanic Activity

    Science.gov (United States)

    van Manen, S. M.; Chen, S.

    2015-12-01

    Here we present an App designed to visualize and identify patterns in volcanic activity during the last ten years. It visualizes VEI (volcanic explosivity index) levels, population size, frequency of activity, and geographic region, and is designed to address the issue of oversampling of data. Often times, it is difficult to access a large set of data that can be scattered at first glance and hard to digest without visual aid. This App serves as a model that solves this issue and can be applied to other data. To enable users to quickly assess the large data set it breaks down the apparently chaotic abundance of information into categories and graphic indicators: color is used to indicate the VEI level, size for population size within 5 km of a volcano, line thickness for frequency of activity, and a grid to pinpoint a volcano's latitude. The categories and layers within them can be turned on and off by the user, enabling them to scroll through and compare different layers of data. By visualising the data this way, patterns began to emerge. For example, certain geographic regions had more explosive eruptions than others. Another good example was that low frequency larger impact volcanic eruptions occurred more irregularly than smaller impact volcanic eruptions, which had a more stable frequencies. Although these findings are not unexpected, the easy to navigate App does showcase the potential of data visualization for the rapid appraisal of complex and abundant multi-dimensional geoscience data.

  18. Link of volcanic activity and climate change in Altai studied in the ice core from Belukha Mountain

    Directory of Open Access Journals (Sweden)

    N. S. Malygina

    2013-01-01

    Full Text Available In the present research we discuss a role of volcanic activity in Altai thermal regime. Here we analyses the sulfate and temperature data reconstructed from the natural paleoarchive – ice core from the Belukha Mountain saddle. Sulfate ice-core reconstructions can serve as volcanic markers. The both – sulfate and temperature reconstructions – are for the last 750 years. As the characteristic of volcanic activity we consider Volcanic Explosivity Index (VEI, Dust Veil Index (DVI and Ice core volcanic index (IVI. The analysis was done using wavelet analysis and analysis of wavelet cross coherence and phase. As the result, we conclude that observed increases in the values of the indexes VEI, DVI, IVI basically correspond to decreases of temperature and increases of sulfate concentrations. This confirms the dependence of changes in the thermal regime of the Altai from volcanic activity. But in the 1750–1850 years period there is a delay of the changes in temperature with respect to the changes in volcanic activity. We suggest that it can be due to the superposition of the influence of solar and volcanic activity on changes in the thermal regime of Altai.

  19. Volcanic Alert System (VAS) developed during the (2011-2013) El Hierro (Canary Islands) volcanic process

    Science.gov (United States)

    Ortiz, Ramon; Berrocoso, Manuel; Marrero, Jose Manuel; Fernandez-Ros, Alberto; Prates, Gonçalo; De la Cruz-Reyna, Servando; Garcia, Alicia

    2014-05-01

    In volcanic areas with long repose periods (as El Hierro), recently installed monitoring networks offer no instrumental record of past eruptions nor experience in handling a volcanic crisis. Both conditions, uncertainty and inexperience, contribute to make the communication of hazard more difficult. In fact, in the initial phases of the unrest at El Hierro, the perception of volcanic risk was somewhat distorted, as even relatively low volcanic hazards caused a high political impact. The need of a Volcanic Alert System became then evident. In general, the Volcanic Alert System is comprised of the monitoring network, the software tools for the analysis of the observables, the management of the Volcanic Activity Level, and the assessment of the threat. The Volcanic Alert System presented here places special emphasis on phenomena associated to moderate eruptions, as well as on volcano-tectonic earthquakes and landslides, which in some cases, as in El Hierro, may be more destructive than an eruption itself. As part of the Volcanic Alert System, we introduce here the Volcanic Activity Level which continuously applies a routine analysis of monitoring data (particularly seismic and deformation data) to detect data trend changes or monitoring network failures. The data trend changes are quantified according to the Failure Forecast Method (FFM). When data changes and/or malfunctions are detected, by an automated watchdog, warnings are automatically issued to the Monitoring Scientific Team. Changes in the data patterns are then translated by the Monitoring Scientific Team into a simple Volcanic Activity Level, that is easy to use and understand by the scientists and technicians in charge for the technical management of the unrest. The main feature of the Volcanic Activity Level is its objectivity, as it does not depend on expert opinions, which are left to the Scientific Committee, and its capabilities for early detection of precursors. As a consequence of the El Hierro

  20. Evidence of recent deep magmatic activity at Cerro Bravo-Cerro Machín volcanic complex, central Colombia. Implications for future volcanic activity at Nevado del Ruiz, Cerro Machín and other volcanoes

    Science.gov (United States)

    Londono, John Makario

    2016-09-01

    In the last nine years (2007-2015), the Cerro Bravo-Cerro Machín volcanic complex (CBCMVC), located in central Colombia, has experienced many changes in volcanic activity. In particular at Nevado del Ruiz volcano (NRV), Cerro Machin volcano (CMV) and Cerro Bravo (CBV) volcano. The recent activity of NRV, as well as increasing seismic activity at other volcanic centers of the CBCMVC, were preceded by notable changes in various geophysical and geochemical parameters, that suggests renewed magmatic activity is occurring at the volcanic complex. The onset of this activity started with seismicity located west of the volcanic complex, followed by seismicity at CBV and CMV. Later in 2010, strong seismicity was observed at NRV, with two small eruptions in 2012. After that, seismicity has been observed intermittently at other volcanic centers such as Santa Isabel, Cerro España, Paramillo de Santa Rosa, Quindío and Tolima volcanoes, which persists until today. Local deformation was observed from 2007 at NRV, followed by possible regional deformation at various volcanic centers between 2011 and 2013. In 2008, an increase in CO2 and Radon in soil was observed at CBV, followed by a change in helium isotopes at CMV between 2009 and 2011. Moreover, SO2 showed an increase from 2010 at NRV, with values remaining high until the present. These observations suggest that renewed magmatic activity is currently occurring at CBCMVC. NRV shows changes in its activity that may be related to this new magmatic activity. NRV is currently exhibiting the most activity of any volcano in the CBCMVC, which may be due to it being the only open volcanic system at this time. This suggests that over the coming years, there is a high probability of new unrest or an increase in volcanic activity of other volcanoes of the CBCMVC.

  1. Geomorphological evolution of volcanic fluvial channels: Eighteen years of morphological monitoring of the upper strect of the Tenenepanco Gorge, Popocatépetl volcano, Mexico

    Science.gov (United States)

    Tanarro, Luis Miguel; Juan Zamorano, Jose; Andres, Nuria; Palacios, David

    2015-04-01

    During volcanic eruptions a significant volume of material accumulates on the slopes and pre-existing gorges of the stratovolcanoes. This abundance of loose and unconsolidated material is very likely to be mobilized by rapid flows or lahars generated by sudden heavy rain or melting snow and ice. Thus, volcanic gorges are affected by complex cycles of incision, filling and widening, altering the equilibrium of river systems due to the major changes that lahars cause in channel morphology. These geomorphological dynamics characterize the gorges located on the north flank of the Popocatépetl volcano (19°02' N, 98°62' W, 5424 m). This volcano, located in the centre of the Trans-Mexican Volcanic Belt, began its most recent eruptive period in December 1994, when a glacier partially covered the northern slope. Since then, the interaction of volcanic and glacier activity triggered the formation of lahars in the gorges, causing significant morphological changes in the channel (especially in April 1995, July 1997 and January 2001). The most recent major eruption at Popocatépetl took place on 19 July 2003, and since then a series of smaller eruptions has reduced the glacier to near extinction. The aim of this study is to assess the morphological response of the Tenenepanco channel over an 18-year period, from 1995-2013, where two main scenarios can be observed: a) the period from 1995 to 2001 of volcanic activity and glacier retreat with the formation of flows and b) the period from 2002 to 2013 of relative volcanic calm, the almost complete extinction of the glacier, and the formation of secondary lahars associated with heavy rainfall. Monitoring of the gorge has consisted in the elaboration of 14 geomorphological maps during field studies (November 14, 1995, December 5, 1997, February 7, 1998, October 6, 2001, November 14, 1995, December 5, 1997, February 7, 1998, October 6, 2001, Julio 16, 2002, February 11, 2004, September 8, 2004, February 5, 2006, November 2, 2008

  2. Compilation of Disruptions to Airports by Volcanic Activity (Version 1.0, 1944-2006)

    Science.gov (United States)

    Guffanti, Marianne; Mayberry, Gari C.; Casadevall, Thomas J.; Wunderman, Richard

    2008-01-01

    Volcanic activity has caused significant hazards to numerous airports worldwide, with local to far-ranging effects on travelers and commerce. To more fully characterize the nature and scope of volcanic hazards to airports, we collected data on incidents of airports throughout the world that have been affected by volcanic activity, beginning in 1944 with the first documented instance of damage to modern aircraft and facilities in Naples, Italy, and extending through 2006. Information was gleaned from various sources, including news outlets, volcanological reports (particularly the Smithsonian Institution's Bulletin of the Global Volcanism Network), and previous publications on the topic. This report presents the full compilation of the data collected. For each incident, information about the affected airport and the volcanic source has been compiled as a record in a Microsoft Access database. The database is incomplete in so far as incidents may not have not been reported or documented, but it does present a good sample from diverse parts of the world. Not included are en-route diversions to avoid airborne ash clouds at cruise altitudes. The database has been converted to a Microsoft Excel spreadsheet. To make the PDF version of table 1 in this open-file report resemble the spreadsheet, order the PDF pages as 12, 17, 22; 13, 18, 23; 14, 19, 24; 15, 20, 25; and 16, 21, 26. Analysis of the database reveals that, at a minimum, 101 airports in 28 countries were impacted on 171 occasions from 1944 through 2006 by eruptions at 46 volcanoes. The number of affected airports (101) probably is better constrained than the number of incidents (171) because recurring disruptions at a given airport may have been lumped together or not reported by news agencies, whereas the initial disruption likely is noticed and reported and thus the airport correctly counted.

  3. Tectonic, volcanic and human activity ground deformation signals detected by multitemporal InSAR techniques in the Colima Volcanic Complex (Mexico) rift

    Science.gov (United States)

    Brunori, C.; Norini, G.; Bignami, C.; Groppelli, G.; Zucca, F.; Stramondo, S.; Capra, L.; Cabral-Cano, E.

    2010-12-01

    The evolution of volcanoes is strictly related with their substratum and the regional tectonics. The link among morphology, geology and structure of volcanic edifices and the geological-structural characteristics of the basement is important to understand hazardous phenomena as flank eruptions and lateral collapses of volcanoes. The Colima Rift is an active regional structure, N-S oriented and more than 100 km long and 10 wide. This rift is filled by a ~1 km-thick sequence of quaternary lacustrine sediments, alluvium, and colluvium, mostly underling the about 3000 m thick volcanic pile of the Colima Volcanic Complex (CVC). In addition to the regional structures curved faults, roughly E-W oriented, are observed on the CVC edifice due to the spreading of the volcano moving southward on the weak basement. So in the CVC edifice and surrounding area we can observe the interaction of regional structures and volcanic ones due to the gravitational loading of the volcanic edifice on the weak substratum of the graben. To measure displacements due to magma movement at depth and interaction of regional structures and volcanic ones, SAR interferometry has proven to be a reliable method; however, andesitic stratovolcanoes like the CVC indeed,remain difficult to survey using this technique. The main causes are their specific geometry (steep topography), which induces strong tropospheric artefacts, environmental conditions (e.g., mainly vegetation, ash and/or snow cover), leading to a loss of coherency. In this work we try to detect deformations phenomena for the wide CVC using a robust multitemporal InSAR approach Differential Synthetic Aperture Radar Interferometry (DInSAR). We apply the Hooper (2008) DInSAR algorithm (StamPS/MTI) both to ENVISAT ASARr images acquired from 1993 to 2007 and to ALOS PALSAR (datasets from 2006 to 2010) in order to determine the deformation patterns in the CVC.

  4. Monitoring the NW volcanic rift-zone of Tenerife, Canary Islands, Spain: sixteen years of diffuse CO_{2} degassing surveys

    Science.gov (United States)

    Rodríguez, Fátima; Halliwell, Simon; Butters, Damaris; Padilla, Germán; Padrón, Eleazar; Hernández, Pedro A.; Pérez, Nemesio M.

    2016-04-01

    Tenerife is the largest of the Canary Islands and, together with Gran Canaria, is the only one that has developed a central volcanic complex characterized by the eruption of differentiated magmas. At present, one of the most active volcanic structures in Tenerife is the North-West Rift-Zone (NWRZ), which has hosted two historical eruptions: Arenas Negras in 1706 and Chinyero in 1909. Since the year 2000, 47 soil CO2 efflux surveys have been undertaken at the NWRZ of Tenerife Island to evaluate the temporal and spatial variations of CO2 efflux and their relationships with the volcanic-seismic activity. We report herein the last results of diffuse CO2 efflux survey at the NWRZ carried out in July 2015 to constrain the total CO2 output from the studied area. Measurements were performed in accordance with the accumulation chamber method. Spatial distribution maps were constructed following the sequential Gaussian simulation (sGs) procedure. During 2015 survey, soil CO2 efflux values ranged from non-detectable up to 103 g m-2 d-1. The total diffuse CO2 output released to atmosphere was estimated at 403 ± 17 t d-1, values higher than the background CO2 emission estimated on 143 t d-1. For all campaigns, soil CO2 efflux values ranged from non-detectable up to 141 g m-2 d-1, with the highest values measured in May 2005. Total CO2 output from the studied area ranged between 52 and 867 t d-1. Temporal variations in the total CO2 output showed a temporal correlation with the onsets of seismic activity, supporting unrest of the volcanic system, as is also suggested by anomalous seismic activity recorded in the area during April 22-29, 2004. Spatial distribution of soil CO2 efflux values also showed changes in magnitude and amplitude, with higher CO2 efflux values located along a trending WNW-ESE area. Subsurface magma movement is proposed as a cause for the observed changes in the total output of diffuse CO2 emission, as well as for the spatial distribution of soil CO2 efflux

  5. Electrical activity during the 2006 Mount St. Augustine volcanic eruptions

    Science.gov (United States)

    Thomas, Ronald J.; Krehbiel, Paul R.; Rison, William; Edens, H. E.; Aulich, G. D.; McNutt, S.R.; Tytgat, Guy; Clark, E.

    2007-01-01

    By using a combination of radio frequency time-of-arrival and interferometer measurements, we observed a sequence of lightning and electrical activity during one of Mount St. Augustine's eruptions. The observations indicate that the electrical activity had two modes or phases. First, there was an explosive phase in which the ejecta from the explosion appeared to be highly charged upon exiting the volcano, resulting in numerous apparently disorganized discharges and some simple lightning. The net charge exiting the volcano appears to have been positive. The second phase, which followed the most energetic explosion, produced conventional-type discharges that occurred within plume. Although the plume cloud was undoubtedly charged as a result of the explosion itself, the fact that the lightning onset was delayed and continued after and well downwind of the eruption indicates that in situ charging of some kind was occurring, presumably similar in some respects to that which occurs in normal thunderstorms.

  6. An FP7 "Space" project: Aphorism "Advanced PRocedures for volcanic and Seismic Monitoring"

    Science.gov (United States)

    Di Iorio, A., Sr.; Stramondo, S.; Bignami, C.; Corradini, S.; Merucci, L.

    2014-12-01

    APHORISM project proposes the development and testing of two new methods to combine Earth Observation satellite data from different sensors, and ground data. The aim is to demonstrate that this two types of data, appropriately managed and integrated, can provide new improved GMES products useful for seismic and volcanic crisis management. The first method, APE - A Priori information for Earthquake damage mapping, concerns the generation of maps to address the detection and estimate of damage caused by a seism. The use of satellite data to investigate earthquake damages is not an innovative issue. We can find a wide literature and projects concerning such issue, but usually the approach is only based on change detection techniques and classifications algorithms. The novelty of APE relies on the exploitation of a priori information derived by InSAR time series to measure surface movements, shake maps obtained from seismological data, and vulnerability information. This a priori information is then integrated with change detection map to improve accuracy and to limit false alarms. The second method deals with volcanic crisis management. The method, MACE - Multi-platform volcanic Ash Cloud Estimation, concerns the exploitation of GEO (Geosynchronous Earth Orbit) sensor platform, LEO (Low Earth Orbit) satellite sensors and ground measures to improve the ash detection and retrieval and to characterize the volcanic ash clouds. The basic idea of MACE consists of an improvement of volcanic ash retrievals at the space-time scale by using both the LEO and GEO estimations and in-situ data. Indeed the standard ash thermal infrared retrieval is integrated with data coming from a wider spectral range from visible to microwave. The ash detection is also extended in case of cloudy atmosphere or steam plumes. APE and MACE methods have been defined in order to provide products oriented toward the next ESA Sentinels satellite missions.The project is funded under the European Union FP7

  7. Hawaiian oral tradition describes 400 years of volcanic activity at Kīlauea

    Science.gov (United States)

    Swanson, Donald A.

    2008-01-01

    Culturally significant oral tradition involving Pele, the Hawaiian volcano deity, and her youngest sister Hi'iaka may involve the two largest volcanic events to have taken place in Hawai'i since human settlement: the roughly 60-year-long ‘Ailā’au eruption during the 15th century and the following development of Kīlauea's caldera. In 1823, Rev. William Ellis and three others became the first Europeans to visit Kīlauea's summit and were told stories about Kīlauea's activity that are consistent with the Pele–Hi'iaka account and extend the oral tradition through the 18th century. Recent geologic studies confirm the essence of the oral traditions and illustrate the potential value of examining other Hawaiian chants and stories for more information about past volcanic activity in Hawai‘i.

  8. 2003-2004 Campaign GPS Geodetic Monitoring of Surface Deformation Proximal to Volcanic Centers, Commonwealth of Dominica, Lesser Antilles.

    Science.gov (United States)

    Davidson, R. T.; Turner, H. L.; Blessing, B. C.; Parra, J.; Fitzgibbon, K.; Jansma, P.; Mattioli, G.

    2004-12-01

    The Commonwealth of Dominica, located midway along the Lesser Antilles island arc, is home to several (at least eight) potentially active volcanic centers. Spurred by recent seismic crises on the island - in the south from 1998-2000 and in the north in 2003 - twelve GPS monuments were installed in two field campaigns in 2001 and 2003. All twelve sites, along with five of six newly installed sites, were occupied continuously for ~2.5 or more UTC days in 2004 using Ashtech Z-12 dual-frequency, code-phase receivers and choke ring antenna to assess the highly complex and possibly interconnected volcanic systems of Dominica. We examine data from the 2003-2004 epochs because of the highly variable, shallow seismicity preceding this period. This way one can potentially isolate the changes that occurred without the data from previous observations influencing the results. Although only two epochs have been included, data quality and reliability can be established from sites distant from volcanic centers, as such sites show consistent velocities from all three epochs of observation over the 2001-2004 period. Between 2003 and 2004, multiple sites show velocities that are inconsistent with a simple tectonic interpretation of elastic strain accumulation along the plate interface. Sites located in the vicinity of the volcanic centers in the south central part of the island are moving faster than the 3 epoch 2001-2004 average of the velocities, which is approximately 7mm/year. The four sites at which greater movement has been noted have velocities ranging from approximately 10 to 27 mm/year. We note that the largest surface deformation signal is seen in the south during the same period when the shallow seismicity was at a maximum in the north of the island. While the spatial distribution of sites remains sparse and the velocities relatively imprecise, the preliminary results may indicate shallow magmatic emplacement, geothermal fluctuations, or structural instability in that part

  9. Evidence of volcanic and glacial activity in Chryse and Acidalia Planitiae, Mars

    Science.gov (United States)

    Martinez-Alonso, Sara; Mellon, Michael T.; Banks, Maria E.; Keszthelyi, Laszlo P.; McEwen, Alfred S.

    2011-01-01

    Chryse and Acidalia Planitiae show numerous examples of enigmatic landforms previously interpreted to have been influenced by a water/ice-rich geologic history. These landforms include giant polygons bounded by kilometer-scale arcuate troughs, bright pitted mounds, and mesa-like features. To investigate the significance of the last we have analyzed in detail the region between 60°N, 290°E and 10°N, 360°E utilizing HiRISE (High Resolution Imaging Science Experiment) images as well as regional-scale data for context. The mesas may be analogous to terrestrial tuyas (emergent sub-ice volcanoes), although definitive proof has not been identified. We also report on a blocky unit and associated landforms (drumlins, eskers, inverted valleys, kettle holes) consistent with ice-emplaced volcanic or volcano-sedimentary flows. The spatial association between tuya-like mesas, ice-emplaced flows, and further possible evidence of volcanism (deflated flow fronts, volcanic vents, columnar jointing, rootless cones), and an extensive fluid-rich substratum (giant polygons, bright mounds, rampart craters), allows for the possibility of glaciovolcanic activity in the region.Landforms indicative of glacial activity on Chryse/Acidalia suggest a paleoclimatic environment remarkably different from today's. Climate changes on Mars (driven by orbital/obliquity changes) or giant outflow channel activity could have resulted in ice-sheet-related landforms far from the current polar caps.

  10. MIGRATION OF SEISMIC AND VOLCANIC ACTIVITY AS DISPLAY OF WAVE GEODYNAMIC PROCESS

    Directory of Open Access Journals (Sweden)

    Alexander V. Vikulin

    2015-09-01

    Full Text Available Publications about the earthquake foci migration have been reviewed. An important result of such studies is establishment of wave nature of seismic activity migration that is manifested by two types of rotational waves; such waves are responsible for interaction between earthquakes foci and propagate with different velocities. Waves determining long-range interaction of earthquake foci are classified as Type 1; their limiting velocities range from 1 to 10 cm/s. Waves determining short-range interaction of foreshocks and aftershocks of individual earthquakes are classified as Type 2; their velocities range from 1 to 10 km/s. According to the classification described in [Bykov, 2005], these two types of migration waves correspond to slow and fast tectonic waves. The most complete data on earthquakes (for a period over 4.1 million of years and volcanic eruptions (for 12 thousand years of the planet are consolidated in a unified systematic format and analyzed by methods developed by the authors. For the Pacific margin, Alpine-Himalayan belt and the Mid-Atlantic Ridge, which are the three most active zones of the Earth, new patterns of spatial and temporal distribution of seismic and volcanic activity are revealed; they correspond to Type 1 of rotational waves. The wave nature of the migration of seismic and volcanic activity is confirmed. A new approach to solving problems of geodynamics is proposed with application of the data on migration of seismic and volcanic activity, which are consolidated in this study, in combination with data on velocities of movement of tectonic plate boundaries. This approach is based on the concept of integration of seismic, volcanic and tectonic processes that develop in the block geomedium and interact with each other through rotating waves with a symmetric stress tensor. The data obtained in this study give grounds to suggest that a geodynamic value, that is mechanically analogous to an impulse

  11. Acoustic waves in the atmosphere and ground generated by volcanic activity

    Energy Technology Data Exchange (ETDEWEB)

    Ichihara, Mie; Lyons, John; Oikawa, Jun; Takeo, Minoru [Earthquake Research Institute, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Instituto Geofisico, Escuela Politecnica Nacional, Ladron de Guevara E11-253, Aptdo 2759, Quito (Ecuador); Earthquake Research Institute, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan)

    2012-09-04

    This paper reports an interesting sequence of harmonic tremor observed in the 2011 eruption of Shinmoe-dake volcano, southern Japan. The main eruptive activity started with ashcloud forming explosive eruptions, followed by lava effusion. Harmonic tremor was transmitted into the ground and observed as seismic waves at the last stage of the effusive eruption. The tremor observed at this stage had unclear and fluctuating harmonic modes. In the atmosphere, on the other hand, many impulsive acoustic waves indicating small surface explosions were observed. When the effusion stopped and the erupted lava began explosive degassing, harmonic tremor started to be transmitted also to the atmosphere and observed as acoustic waves. Then the harmonic modes became clearer and more stable. This sequence of harmonic tremor is interpreted as a process in which volcanic degassing generates an open connection between the volcanic conduit and the atmosphere. In order to test this hypothesis, a laboratory experiment was performed and the essential features were successfully reproduced.

  12. Updating Parameters for Volcanic Hazard Assessment Using Multi-parameter Monitoring Data Streams And Bayesian Belief Networks

    Science.gov (United States)

    Odbert, Henry; Aspinall, Willy

    2014-05-01

    Evidence-based hazard assessment at volcanoes assimilates knowledge about the physical processes of hazardous phenomena and observations that indicate the current state of a volcano. Incorporating both these lines of evidence can inform our belief about the likelihood (probability) and consequences (impact) of possible hazardous scenarios, forming a basis for formal quantitative hazard assessment. However, such evidence is often uncertain, indirect or incomplete. Approaches to volcano monitoring have advanced substantially in recent decades, increasing the variety and resolution of multi-parameter timeseries data recorded at volcanoes. Interpreting these multiple strands of parallel, partial evidence thus becomes increasingly complex. In practice, interpreting many timeseries requires an individual to be familiar with the idiosyncrasies of the volcano, monitoring techniques, configuration of recording instruments, observations from other datasets, and so on. In making such interpretations, an individual must consider how different volcanic processes may manifest as measureable observations, and then infer from the available data what can or cannot be deduced about those processes. We examine how parts of this process may be synthesised algorithmically using Bayesian inference. Bayesian Belief Networks (BBNs) use probability theory to treat and evaluate uncertainties in a rational and auditable scientific manner, but only to the extent warranted by the strength of the available evidence. The concept is a suitable framework for marshalling multiple strands of evidence (e.g. observations, model results and interpretations) and their associated uncertainties in a methodical manner. BBNs are usually implemented in graphical form and could be developed as a tool for near real-time, ongoing use in a volcano observatory, for example. We explore the application of BBNs in analysing volcanic data from the long-lived eruption at Soufriere Hills Volcano, Montserrat. We discuss

  13. Yanshan, Gaoshan-Two Active Volcanoes of the Volcanic Cluster in Arshan, Inner Mongolia

    Institute of Scientific and Technical Information of China (English)

    Bai Zhida; Tian Mingzhong; Wu Fadong; Xu Debing; Li Tuanjie

    2005-01-01

    The volcanic cluster in Arshan, Inner Mongolia, is located in the west of the middle section of the Da Hinggan Mountains. There are more than forty Cenozoic volcanoes among which the Yanshan Volcano and Gaoshan Volcano are the active ones in broad sense and basaltic central vents. Arshan is a newly found volcanic active region in the Chinese continent. The volcanoes are perfectly preserved and composed of cinder cones, pyroclastic sheets and lava flows. Their cones are grand and the Gaoshan cone is about 362m high, and the depth of the Yanshan crater is about 140m. The pyroclastic sheet is mainly made up of scoria, and the distribution area of scoria with thickness more than 1m is about 27km2. There are two Carbonized-wood sites in the pyroclastic sheet and the 14C datings indicate ages of 1990 ± 100a B. P and 1900 ±70a B. P, which are rectified by dendrodating. Basaltic lava flows are uncovered, and they change from pahoehoe in the early stage to aa in the later stage. There are lots of perfect fumarolic cones, fumarolic dishes and lava tumulus in the front zones. The spread of lava flow is controlled by the local topography and its main body flowed northwestwards covering the Holocene rivers and swamp deposits and blocked up the Halahahe river and its branches to create six lava-dam lakes. For these distinguishing features, Arshan volcanic cluster could be called another natural "Volcano Museum".

  14. Early Analysis of Landsat-8 Thermal Infrared Sensor Imagery of Volcanic Activity

    Directory of Open Access Journals (Sweden)

    Matthew Blackett

    2014-03-01

    Full Text Available The Landsat-8 satellite of the Landsat Data Continuity Mission was launched by the National Aeronautics and Space Administration (NASA in April 2013. Just weeks after it entered active service, its sensors observed activity at Paluweh Volcano, Indonesia. Given that the image acquired was in the daytime, its shortwave infrared observations were contaminated with reflected solar radiation; however, those of the satellite’s Thermal Infrared Sensor (TIRS show thermal emission from the volcano’s summit and flanks. These emissions detected in sensor’s band 10 (10.60–11.19 µm have here been quantified in terms of radiant power, to confirm reports of the actual volcanic processes operating at the time of image acquisition, and to form an initial assessment of the TIRS in its volcanic observation capabilities. Data from band 11 have been neglected as its data have been shown to be unreliable at the time of writing. At the instant of image acquisition, the thermal emission of the volcano was found to be 345 MW. This value is shown to be on the same order of magnitude as similarly timed NASA Earth Observing System (EOS Moderate Resolution Imaging Spectroradiometer thermal observations. Given its unique characteristics, the TIRS shows much potential for providing useful, detailed and accurate volcanic observations in the future.

  15. Overview of electromagnetic methods applied in active volcanic areas of western United States

    Science.gov (United States)

    Skokan, Catherine K.

    1993-06-01

    A better understanding of active volcanic areas in the United States through electromagnetic geophysical studies received foundation from the many surveys done for geothermal exploration in the 1970's. Investigations by governmental, industrial, and academic agencies include (but are not limited to) mapping of the Cascades. Long Valley/Mono area, the Jemez volcanic field, Yellowstone Park, and an area in Colorado. For one example — Mt. Konocti in the Mayacamas Mountains, California — gravity, magnetic, and seismic, as well as electromagnetic methods have all been used in an attempt to gain a better understanding of the subsurface structure. In each of these volcanic regions, anomalous zones were mapped. When conductive, these anomalies were interpreted to be correlated with hydrothermal activity and not to represent a magma chamber. Electrical and electromagnetic geophysical methods can offer valuable information in the understanding of volcanoes by being the method which is most sensitive to change in temperature and, therefore, can best map heat budget and hydrological character to aid in prediction of eruptions.

  16. Using CATS Near-Real-time Lidar Observations to Monitor and Constrain Volcanic Sulfur Dioxide (SO2) Forecasts

    Science.gov (United States)

    Hughes, E. J.; Yorks, J.; Krotkov, N. A.; da Silva, A. M.; Mcgill, M.

    2016-01-01

    An eruption of Italian volcano Mount Etna on 3 December 2015 produced fast-moving sulfur dioxide (SO2) and sulfate aerosol clouds that traveled across Asia and the Pacific Ocean, reaching North America in just 5 days. The Ozone Profiler and Mapping Suite's Nadir Mapping UV spectrometer aboard the U.S. National Polar-orbiting Partnership satellite observed the horizontal transport of the SO2 cloud. Vertical profiles of the colocated volcanic sulfate aerosols were observed between 11.5 and 13.5 km by the new Cloud Aerosol Transport System (CATS) space-based lidar aboard the International Space Station. Backward trajectory analysis estimates the SO2 cloud altitude at 7-12 km. Eulerian model simulations of the SO2 cloud constrained by CATS measurements produced more accurate dispersion patterns compared to those initialized with the back trajectory height estimate. The near-real-time data processing capabilities of CATS are unique, and this work demonstrates the use of these observations to monitor and model volcanic clouds.

  17. Lake-floor sediment texture and composition of a hydrothermally-active, volcanic lake, Lake Rotomahana

    Science.gov (United States)

    Pittari, A.; Muir, S. L.; Hendy, C. H.

    2016-03-01

    Young volcanic lakes undergo a transition from rapid, post-eruptive accumulation of volcaniclastic sediment to slower pelagic settling under stable lake conditions, and may also be influenced by sublacustrine hydrothermal systems. Lake Rotomahana is a young (129 year-old), hydrothermally-active, volcanic lake formed after the 1886 Tarawera eruption, and provides a unique insight into the early evolution of volcanic lake systems. Lake-bottom sediment cores, 20-46 cm in length, were taken along a transect across the lake and characterised with respect to stratigraphy, facies characteristics (i.e., grain size, componentry) and pore water silica concentrations. The sediments generally comprise two widespread facies: (i) a lower facies of light grey to grey, very fine lacustrine silt derived from the unconsolidated pyroclastic deposits that mantled the catchment area immediately after the eruption, which were rapidly reworked and redeposited into the lake basin; and (ii) an upper facies of dark, fine-sandy diatomaceous silt, that settled from the pelagic zone of the physically stable lake. Adjacent to sublacustrine hydrothermal vents, the upper dark facies is absent, and the upper part of the light grey to grey silt is replaced by a third localised facies comprised of hydrothermally altered pale yellow to yellowish brown, laminated silt with surface iron-rich encrustations. Microspheres, which are thought to be composed of amorphous silica, although some may be halloysite, have precipitated from pore water onto sediment grains, and are associated with a decrease in pore water silicon concentration. Lake Rotomahana is an example of a recently-stabilised volcanic lake, with respect to sedimentation, that shows signs of early sediment silicification in the presence of hydrothermal activity.

  18. Requirements and Implementation Feasibility for a CubeSat Thermal Infrared Imaging System to Monitor the Structure of Volcanic Ash Clouds

    Science.gov (United States)

    Thorsen, D.; Carroll, R.; Webley, P.; Hawkins, J.

    2014-12-01

    The 2010 eruption of the Eyjafjallajökull volcano in Iceland caused the cancellation of approximately 108,000 flights over an 8-day period, disrupted air traffic worldwide, and cost the airline industry more than $400 million per day. The inconvenience and economic impact of this and similar events, such as Puyehue-Cordon-Caulle in 2011, have heightened the interest in developing improved satellite remote sensing techniques for monitoring volcanic plumes and drifting clouds. For aviation safety, the operational/research community has started to move towards classifying the concentrations within volcanic plumes and clouds. Additionally, volcanic ash transport and dispersion (VATD) models are often used for forecasting ash cloud locations and they require knowledge of the structure of the erupting column to improve their ash simulations and also downwind 3-D maps of the ash cloud to calibrate/validate their modeling output. Existing remote sensing satellites utilize a brightness temperature method with thermal infrared (TIR) measurements from 10 - 12 μm to determine mass loading of volcanic ash along a single line of sight, but they have infrequent revisit times and they cannot resolve the three-dimensional structure of the ash clouds. A cluster of CubeSats dedicated to the monitoring of volcanic ash and plumes could provide both more frequent updates and the multi-aspect images needed to resolve the density structure of volcanic ash clouds and plumes. In this presentation, we discuss the feasibility and requirements for a CubeSat TIR imaging system and the associated on-board image processing that would be required to monitor the structure of volcanic ash clouds from Low Earth Orbit.

  19. Strategies in the processing and analysis of continuous gravity record in active volcanic areas: the case of Mt. Vesuvius

    Directory of Open Access Journals (Sweden)

    J. Hinderer

    2008-06-01

    Full Text Available This research is intended to describe new strategies in the processing and analysis of continuous gravity records collected in active volcanic areas and to assess how permanent gravity stations can improve the geophysical monitoring of a volcano. The experience of 15 years in continuous gravity monitoring on Mt. Vesuvius is discussed. Several geodynamic phenomena can produce temporal gravity changes. An eruption, for instance, is associated with the ascent of magma producing changes in the density distribution at depth, and leading to ground deformation and gravity changes The amplitude of such gravity variations is often quite small, in the order of 10-102 nms-2, so their detection requires high quality data and a rigorous procedure to isolate from the records those weak gravity signals coming from different sources. Ideally we need gravity signals free of all effects which are not of volcanic origin. Therefore solid Earth tide, ocean and atmospheric loading, instrumental drift or any kind of disturbances other than due to the volcano dynamics have to be removed. The state of the art on the modelling of the solid Earth tide is reviewed. The atmospheric dynamics is one of the main sources precluding the detection of small gravity signals. The most advanced methods to reduce the atmospheric effects on gravity are presented. As the variations of the calibration factors can prevent the repeatability of high-precision measurements, new approaches to model the instrumental response of mechanical gravimeters are proposed too. Moreover, a strategy for an accurate modelling of the instrumental drift and to distinguish it from longterm gravity changes is suggested.

  20. Temporal and geochemical constraints on active volcanism in southeastern Papua New Guinea

    Science.gov (United States)

    Catalano, J. P.; Baldwin, S.; Fitzgerald, P. G.; Webb, L. E.; Hollocher, K.

    2010-12-01

    Active volcanism in southeastern Papua New Guinea occurs on the Papuan Peninsula (Mt. Lamington and Mt. Victory), in the Woodlark Rift (Dobu Island, SE Goodenough Island, and Western Fergusson Island), and in the Woodlark Basin. In the Woodlark Basin seafloor spreading is active and decompression melting of the mantle produces basalts. However, the cause of volcanism on the Papuan Peninsula and immediately west of active seafloor spreading rift tip in the Woodlark Basin is controversial. Previous studies have suggested active volcanism there results from 1) southward subduction of Solomon Sea lithosphere at the Trobriand Trough or 2) decompression melting as the lithosphere is extended and eventually ruptures. To evaluate these possibilities 20 samples were collected from a bimodal basalt-rhyolite suite in the D’Entrecasteaux Islands approximately 80 km west of the sea floor spreading rift tip. Siliceous ash flow tuffs on Dobu Island, Sanaroa Island, and Eastern Fergusson Island consist of sanidine/anorthoclase + Fe/Ti oxides (illmenite/ magnetite) ± quartz ± nepheline ± clinopyroxene ± xenocrystic olivine. Sanidine and K-feldspar from these ash flow tuffs yielded flat age spectra with 40Ar/39Ar isochron ages of 0.008 ± 0.002 Ma and 0.553 ± 0.001 Ma. ICP-MS trace and REE geochemistry on felsic rocks from Dobu Island and Eastern Fergusson Island yielded multi-element diagrams with enriched incompatible elements, and corresponding negative Nb, Sr, Eu, and Ti anomalies. In contrast, mafic volcanics from SE Goodenough Island are comprised of plagioclase + olivine + Fe/Ti oxides ± orthopyroxene ± clinopyroxene ± hornblende ± biotite. Biotite yielded a 40Ar/39Ar isochron age of 0.376 ± 0.05 Ma. MORB-normalized multi-element diagrams of mafic rocks from SE Goodenough Island are LREE-enriched patterns with negative Nb and positive Sr anomalies. In comparison, multi-element diagrams from previous work on mafic rocks from the New Britain arc to the north also

  1. The ELSA tephra stack: Volcanic activity in the Eifel during the last 500,000 years

    Science.gov (United States)

    Förster, Michael W.; Sirocko, Frank

    2016-07-01

    Tephra layers of individual volcanic eruptions are traced in several cores from Eifel maar lakes, drilled between 1998 and 2014 by the Eifel Laminated Sediment Archive (ELSA). All sediment cores are dated by 14C and tuned to the Greenland interstadial succession. Tephra layers were characterized by the petrographic composition of basement rock fragments, glass shards and characteristic volcanic minerals. 10 marker tephra, including the well-established Laacher See Tephra and Dümpelmaar Tephra can be identified in the cores spanning the last glacial cycle. Older cores down to the beginning of the Elsterian, show numerous tephra sourced from Strombolian and phreatomagmatic eruptions, including the 40Ar/39Ar dated differentiated tephra from Glees and Hüttenberg. In total, at least 91 individual tephra can be identified since the onset of the Eifel volcanic activity at about 500,000 b2k, which marks the end of the ELSA tephra stack with 35 Strombolian, 48 phreatomagmatic and 8 tephra layers of evolved magma composition. Many eruptions cluster near timings of the global climate transitions at 140,000, 110,000 and 60,000 b2k. In total, the eruptions show a pattern, which resembles timing of phases of global sea level and continental ice sheet changes, indicating a relation between endogenic and exogenic processes.

  2. Trace elements in scalp hair of children chronically exposed to volcanic activity (Mt. Etna, Italy).

    Science.gov (United States)

    Varrica, D; Tamburo, E; Dongarrà, G; Sposito, F

    2014-02-01

    The aim of this survey was to use scalp hair as a biomonitor to evaluate the environmental exposure to metals and metalloids of schoolchildren living around the Mt. Etna area, and to verify whether the degree of human exposure to trace elements is subject to changes in local environmental factors. Twenty trace elements were determined in 376 samples of scalp hair from schoolboys (11-13 years old) of both genders, living in ten towns located around the volcanic area of Mt. Etna (Sicily). The results were compared with those (215 samples) from children living in areas of Sicily characterized by a different geological setting (reference site). As, U and V showed much higher concentrations at the volcanic site whereas Sr was particularly more abundant at the reference site. Linear Discriminant Analysis (LDA) indicated an Etna factor, made up of V, U and Mn, and a second factor, concerning the reference site, characterized by Ni and Sr, and to a lesser extent by Mo and Cd. Significant differences in element concentrations were also observed among three different sectors of Mt. Etna area. Young people living in the Mt. Etna area are naturally exposed to enhanced intakes of some metals (V, U, Mn) and non-metals (e.g., As) than individuals of the same age residing in other areas of Sicily, characterized by different lithologies and not influenced by volcanic activity. The petrographic nature of local rocks and the dispersion of the volcanic plume explain the differences, with ingestion of water and local food as the most probable exposure pathways.

  3. Assessing microbial activities in metal contaminated agricultural volcanic soils--An integrative approach.

    Science.gov (United States)

    Parelho, C; Rodrigues, A S; Barreto, M C; Ferreira, N G C; Garcia, P

    2016-07-01

    Volcanic soils are unique naturally fertile resources, extensively used for agricultural purposes and with particular physicochemical properties that may result in accumulation of toxic substances, such as trace metals. Trace metal contaminated soils have significant effects on soil microbial activities and hence on soil quality. The aim of this study is to determine the soil microbial responses to metal contamination in volcanic soils under different agricultural land use practices (conventional, traditional and organic), based on a three-tier approach: Tier 1 - assess soil microbial activities, Tier 2 - link the microbial activity to soil trace metal contamination and, Tier 3 - integrate the microbial activity in an effect-based soil index (Integrative Biological Response) to score soil health status in metal contaminated agricultural soils. Our results showed that microbial biomass C levels and soil enzymes activities were decreased in all agricultural soils. Dehydrogenase and β-glucosidase activities, soil basal respiration and microbial biomass C were the most sensitive responses to trace metal soil contamination. The Integrative Biological Response value indicated that soil health was ranked as: organic>traditional>conventional, highlighting the importance of integrative biomarker-based strategies for the development of the trace metal "footprint" in Andosols.

  4. Volcanic activity in the Acambay Graben: a < 25 Ka subplinian eruption from the Temascalcingo volcano and implications for volcanic hazard.

    Science.gov (United States)

    Pedrazzi, Dario; Aguirre Díaz, Gerardo; Sunyé Puchol, Ivan; Bartolini, Stefania; Geyer, Adelina

    2016-04-01

    The Trans-Mexican Volcanic Belt (TMVB) contains a large number of stratovolcanoes, some well-known, as Popocatepetl, Iztaccihuatl, Nevado de Toluca, or Colima and many others of more modest dimensions that are not well known but constitute the majority in the TMVB. Such volcanoes are, for example, Tequila, San Juan, Sangangüey, Cerro Culiacán, Cerro Grande, El Zamorano, La Joya, Palo Huerfano, Jocotitlán, Altamirano and Temascalcingo, among many others. The Temascalcingo volcano (TV) is an andesitic-dacitic stratovolcano located in the Trans-Mexican Volcanic Belt (TMVB) at the eastern part of the Acambay Graben (northwest portion of Estado de México). The TV is composed mainly by dacitic, porphyritic lavas, block and ash deposits and subordinate pumice fall deposits and ignimbrites (Roldán-Quintana et al., 2011). The volcanic structure includes a summit caldera that has a rectangular shape, 2.5×3.5 km, with the largest side oriented E-W, parallel to major normal faults affecting the edifice. The San Mateo Pumice eruption is one of the greatest paroxysmal episodes of this volcano with pumice deposits mainly exposed at the scarp of the Acambay-Tixmadeje fault and at the northern and northeastern flanks of TV. It overlies a paleosol dated at 25 Ka. A NE-trending dispersion was obtained from field data covering an area of at least 80 km2. These deposits overlie older lava flows and mud flows and are discontinuously covered and eroded by younger reworked deposits of Temascalcingo volcano. This event represents a highly explosive phase that generated a relatively thick and widespread pumice fallout deposit that may occur again in future eruptions. A similar eruption today would have a significantly impact in the region, overall due to the fact that there has been no systematic assessment of the volcanic hazard in any of the studies that have been conducted so far in the area. So, this is a pending and urgent subject that must be tackled without delay. Financed by

  5. Scaling and extended scaling in sediment registers of a paleolake perturbed by volcanic activity

    Science.gov (United States)

    Ugalde, Edgardo; Martínez-Mekler, Gustavo; Vilaclara, Gloria

    2006-07-01

    We analyze a sequence of density variations of sedimentary material from an extinct paleolake of the state of Tlaxcala, Mexico, which we previously obtained by means of computer-aided tomography [J. Miranda, A. Oliver, G. Vilaclara, R. Rico-Montiel, V.M. Macias, J.L. Ruvalcava, M.A. Zenteno, Nucl. Instrum. Methods Phys. Res. B 85 (1994) 886]. In the stratified blocks chiselled out of mines at the lake bed, low-density sediments have a high concentration of diatomite, while high-density strata show a considerable amount of material external to the lake, mostly of volcanic origin. Two regions can be distinguished by visual inspection: a darker and older one which we attribute to a strongly externally perturbed regime, and a whiter more recent one which appears to have been subjected to less frequent volcanic perturbations. By means of a scaling analysis of the distribution function of density fluctuations, we show that for the most recent region there is a range of scales where these fluctuations present a self-similar behavior. We attribute this observation to a rare event response, namely, the onset of correlations in the lake relaxation processes to steady-state conditions following intense volcanic disturbances. Based on scaling properties of the structure function, we also show that the complete data series presents extended self-similarity as encountered in turbulence studies [R. Benzi, S. Ciliberto, R. Tripiccione, C. Baudet, F. Massoli, S. Succi, Phys. Rev. E 48 (1993) R29]. Our characterization of the statistical behavior of the density fluctuations contributes to our knowledge of the volcanic activity over a period of thousands of years, as well as aspects of ecological interest of the lake's response to these disturbances [G. Vilaclara, E. Ugalde, E. Cuna, G. Martinez-Mekler, Complex dynamics of the evolution of a Paleolake subjected to volcanic activity: geology meets ecology, submitted for publication]. Our approach can be implemented in general to other

  6. Exploring Hawaiian Volcanism

    Science.gov (United States)

    Poland, Michael P.; Okubo, Paul G.; Hon, Ken

    2013-02-01

    In 1912 the Hawaiian Volcano Observatory (HVO) was established by Massachusetts Institute of Technology professor Thomas A. Jaggar Jr. on the island of Hawaii. Driven by the devastation he observed while investigating the volcanic disasters of 1902 at Montagne Pelée in the Caribbean, Jaggar conducted a worldwide search and decided that Hawai`i provided an excellent natural laboratory for systematic study of earthquake and volcano processes toward better understanding of seismic and volcanic hazards. In the 100 years since HVO's founding, surveillance and investigation of Hawaiian volcanoes have spurred advances in volcano and seismic monitoring techniques, extended scientists' understanding of eruptive activity and processes, and contributed to development of global theories about hot spots and mantle plumes.

  7. Exploring Hawaiian volcanism

    Science.gov (United States)

    Poland, Michael P.; Okubo, Paul G.; Hon, Ken

    2013-01-01

    In 1912 the Hawaiian Volcano Observatory (HVO) was established by Massachusetts Institute of Technology professor Thomas A. Jaggar Jr. on the island of Hawaii. Driven by the devastation he observed while investigating the volcanic disasters of 1902 at Montagne Pelée in the Caribbean, Jaggar conducted a worldwide search and decided that Hawai‘i provided an excellent natural laboratory for systematic study of earthquake and volcano processes toward better understanding of seismic and volcanic hazards. In the 100 years since HVO’s founding, surveillance and investigation of Hawaiian volcanoes have spurred advances in volcano and seismic monitoring techniques, extended scientists’ understanding of eruptive activity and processes, and contributed to development of global theories about hot spots and mantle plumes.

  8. Monitoring priority substances, other organic contaminants and heavy metals in a volcanic aquifer from different sources and hydrological processes

    Energy Technology Data Exchange (ETDEWEB)

    Estevez, Esmeralda, E-mail: eestevez@proyinves.ulpgc.es [Dpt. Física (GEOVOL), Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Canary Islands (Spain); Agrifood and Phytopathological Laboratory (Cabildo de Gran Canaria), 35413 Arucas, Canary Islands (Spain); Cabrera, María del Carmen, E-mail: mcarmen.cabrera@ulpgc.es [Dpt. Física (GEOVOL), Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Canary Islands (Spain); IMDEA Water Institute, Alcalá de Henares, Madrid (Spain); Fernández-Vera, Juan Ramón, E-mail: jrfernandezv@grancanaria.com [Agrifood and Phytopathological Laboratory (Cabildo de Gran Canaria), 35413 Arucas, Canary Islands (Spain); Molina-Díaz, Antonio, E-mail: amolina@ujaen.es [Analytical Chemistry Research Group, Department of Physical and Analytical Chemistry, University of Jaen, 23071 Jaen (Spain); Robles-Molina, José, E-mail: jroblesmol@gmail.com [Analytical Chemistry Research Group, Department of Physical and Analytical Chemistry, University of Jaen, 23071 Jaen (Spain); Palacios-Díaz, María del Pino, E-mail: mp.palaciosdiaz@ulpgc.es [Dpt. de Patología Animal, Producción Animal, Bromatología y Tecnología de los Alimentos (GEOVOL), Universidad de Las Palmas de Gran Canaria, 35413 Arucas, Canary Islands (Spain)

    2016-05-01

    Irrigation with reclaimed water (R) is necessary to guarantee the sustainability of semi-arid areas. Results obtained during a two years monitoring network (2009–2011) in Gran Canaria are presented, including the analysis of chemical parameters, N and S isotopes, priority substances (2008/105/EC, 2013/39/EU), other organic contaminants and heavy metals in groundwater and R used to irrigate a golf course. The aims of this work are to evaluate the contamination in a volcanic aquifer, relate the presence of organic contaminants and heavy metals with the hydrogeochemistry and identify pollution sources in the area. No priority substance exceeded the EU thresholds for surface water, although seventeen were detected in R. The most frequent compounds were hexachlorobenzene, chlorpyrifos ethyl, fluorene, phenanthrene and pyrene. These compounds were detected at low concentration, except chlorpyrifos. Chlorpyrifos ethyl, terbuthylazine, diuron, terbutryn, procymidone, atrazine and propazine exceeded the European threshold concentration for pesticides in groundwater (100 ng L{sup −1}). Therefore, the priority substances chlorpyrifos ethyl and diuron must be included in monitoring studies. The priority pesticides chlorfenvinphos and diazinon were always detected in R but rarely in groundwater. Besides, the existence of contaminants not related to the current R irrigation has been identified. Absence of environmental problems related to heavy metals can be expected. The relationship among contaminant presence, hydrogeochemistry, including the stable isotopic prints of δ{sup 18}O, δ{sup 15}N and δ{sup 34}S and preferential recharge paths has been described. The coastal well shows high values of EC, nitrate, a variable chemistry, and 50% of organic contaminants detected above 100 ng L{sup −1}. The well located in the recharge area presents a stable hydrochemistry, the lowest value of δ{sup 15}N and the lowest contaminants occurrence. The area is an example of a complex

  9. Evidence from acoustic imaging for submarine volcanic activity in 2012 off the west coast of El Hierro (Canary Islands, Spain)

    Science.gov (United States)

    Pérez, Nemesio M.; Somoza, Luis; Hernández, Pedro A.; de Vallejo, Luis González; León, Ricardo; Sagiya, Takeshi; Biain, Ander; González, Francisco J.; Medialdea, Teresa; Barrancos, José; Ibáñez, Jesús; Sumino, Hirochika; Nogami, Kenji; Romero, Carmen

    2014-12-01

    We report precursory geophysical, geodetic, and geochemical signatures of a new submarine volcanic activity observed off the western coast of El Hierro, Canary Islands. Submarine manifestation of this activity has been revealed through acoustic imaging of submarine plumes detected on the 20-kHz chirp parasound subbottom profiler (TOPAS PS18) mounted aboard the Spanish RV Hespérides on June 28, 2012. Five distinct "filament-shaped" acoustic plumes emanating from the flanks of mounds have been recognized at water depth between 64 and 88 m on a submarine platform located NW El Hierro. These plumes were well imaged on TOPAS profiles as "flares" of high acoustic contrast of impedance within the water column. Moreover, visible plumes composed of white rafts floating on the sea surface and sourcing from the location of the submarine plumes were reported by aerial photographs on July 3, 2012, 5 days after acoustic plumes were recorded. In addition, several geophysical and geochemical data support the fact that these submarine vents were preceded by several precursory signatures: (i) a sharp increase of the seismic energy release and the number of daily earthquakes of magnitude ≥2.5 on June 25, 2012, (ii) significant vertical and horizontal displacements observed at the Canary Islands GPS network (Nagoya University-ITER-GRAFCAN) with uplifts up to 3 cm from June 25 to 26, 2012, (iii) an anomalous increase of the soil gas radon activity, from the end of April until the beginning of June reaching peak values of 2.7 kBq/m3 on June 3, 2012, and (iv) observed positive peak in the air-corrected value of 3He/4He ratio monitored in ground waters (8.5 atmospheric 3He/4He ratio ( R A)) at the northwestern El Hierro on June 16, 2012. Combining these submarine and subaerial information, we suggest these plumes are the consequence of submarine vents exhaling volcanic gas mixed with fine ash as consequence of an event of rapid rise of volatile-rich magma beneath the NW submarine ridge

  10. The Cenozoic volcanism in the Kivu rift: Assessment of the tectonic setting, geochemistry, and geochronology of the volcanic activity in the South-Kivu and Virunga regions

    Science.gov (United States)

    Pouclet, A.; Bellon, H.; Bram, K.

    2016-09-01

    The Kivu rift is part of the western branch of the East African Rift system. From Lake Tanganyika to Lake Albert, the Kivu rift is set in a succession of Precambrian zones of weakness trending NW-SE, NNE-SSW and NE-SW. At the NW to NNE turn of the rift direction in the Lake Kivu area, the inherited faults are crosscut by newly born N-S fractures which developed during the late Cenozoic rifting and controlled the volcanic activity. From Lake Kivu to Lake Edward, the N-S faults show a right-lateral en echelon pattern. Development of tension gashes in the Virunga area indicates a clockwise rotation of the constraint linked to dextral oblique motion of crustal blocks. The extensional direction was W-E in the Mio-Pliocene and ENE-WSW in the Pleistocene to present time. The volcanic rocks are assigned to three groups: (1) tholeiites and sodic alkali basalts in the South-Kivu, (2) sodic basalts and nephelinites in the northern Lake Kivu and western Virunga, and (3) potassic basanites and potassic nephelinites in the Virunga area. South-Kivu magmas were generated by melting of spinel + garnet lherzolite from two sources: an enriched lithospheric source and a less enriched mixed lithospheric and asthenospheric source. The latter source was implied in the genesis of the tholeiitic lavas at the beginning of the South-Kivu tectono-volcanic activity, in relationships with asthenosphere upwelling. The ensuing outpouring of alkaline basaltic lavas from the lithospheric source attests for the abortion of the asthenospheric contribution and a change of the rifting process. The sodic nephelinites of the northern Lake Kivu originated from low partial melting of garnet peridotite of the sub-continental mantle due to pressure release during swell initiation. The Virunga potassic magmas resulted from the melting of garnet peridotite with an increasing degree of melting from nephelinite to basanite. They originated from a lithospheric source enriched in both K and Rb, suggesting the

  11. Self-potential, geoelectric and magnetotelluric studies in Italian active volcanic areas

    Directory of Open Access Journals (Sweden)

    A. Siniscalchi

    1997-06-01

    Full Text Available We present the results of self-potential, geoelectric and magnetotelluric studies in Italian active volcanic areas as essential contributions both to structural modeling and to hazard evaluation. On Mt. Etna and Mt. Somma-Vesuvius complexes structural modeling was emphasized due to a lack of global information involving the whole apparatuses, at least from the electrical point of view. Hazard investigation was, instead, investigated with high resolution techniques on the island of Vulcano, where intense unrest phenomena have long been recorded.

  12. Volcanic hazard management in dispersed volcanism areas

    Science.gov (United States)

    Marrero, Jose Manuel; Garcia, Alicia; Ortiz, Ramon

    2014-05-01

    Traditional volcanic hazard methodologies were developed mainly to deal with the big stratovolcanoes. In such type of volcanoes, the hazard map is an important tool for decision-makers not only during a volcanic crisis but also for territorial planning. According to the past and recent eruptions of a volcano, all possible volcanic hazards are modelled and included in the hazard map. Combining the hazard map with the Event Tree the impact area can be zoned and defining the likely eruptive scenarios that will be used during a real volcanic crisis. But in areas of disperse volcanism is very complex to apply the same volcanic hazard methodologies. The event tree do not take into account unknown vents, because the spatial concepts included in it are only related with the distance reached by volcanic hazards. The volcanic hazard simulation is also difficult because the vent scatter modifies the results. The volcanic susceptibility try to solve this problem, calculating the most likely areas to have an eruption, but the differences between low and large values obtained are often very small. In these conditions the traditional hazard map effectiveness could be questioned, making necessary a change in the concept of hazard map. Instead to delimit the potential impact areas, the hazard map should show the expected behaviour of the volcanic activity and how the differences in the landscape and internal geo-structures could condition such behaviour. This approach has been carried out in La Palma (Canary Islands), combining the concept of long-term hazard map with the short-term volcanic scenario to show the expected volcanic activity behaviour. The objective is the decision-makers understand how a volcanic crisis could be and what kind of mitigation measurement and strategy could be used.

  13. Volcanic hazard assessment in monogenetic volcanic fields

    OpenAIRE

    Bartolini, Stefania

    2014-01-01

    [eng] One of the most important tasks of modern volcanology, which represents a significant socio-economic implication, is to conduct hazard assessment in active volcanic systems. These volcanological studies are aimed at hazard that allows to constructing hazard maps and simulating different eruptive scenarios, and are mainly addressed to contribute to territorial planning, definition of emergency plans or managing volcanic crisis. The impact of a natural event, as a volcanic eruption, can s...

  14. 2008 Volcanic activity in Alaska, Kamchatka, and the Kurile Islands: Summary of events and response of the Alaska Volcano Observatory

    Science.gov (United States)

    Neal, Christina A.; McGimsey, Robert G.; Dixon, James P.; Cameron, Cheryl E.; Nuzhdaev, Anton A.; Chibisova, Marina

    2011-01-01

    The Alaska Volcano Observatory (AVO) responded to eruptions, possible eruptions, and volcanic unrest or suspected unrest at seven separate volcanic centers in Alaska during 2008. Significant explosive eruptions at Okmok and Kasatochi Volcanoes in July and August dominated Observatory operations in the summer and autumn. AVO maintained 24-hour staffing at the Anchorage facility from July 12 through August 28. Minor eruptive activity continued at Veniaminof and Cleveland Volcanoes. Observed volcanic unrest at Cook Inlet's Redoubt Volcano presaged a significant eruption in the spring of 2009. AVO staff also participated in hazard communication regarding eruptions or unrest at nine volcanoes in Russia as part of a collaborative role in the Kamchatka and Sakhalin Volcanic Eruption Response Teams.

  15. 7 CFR 800.216 - Activities that shall be monitored.

    Science.gov (United States)

    2010-01-01

    ... merchandising activities identified in this section shall be monitored in accordance with the instructions. (b) Grain merchandising activities. Grain merchandising activities subject to monitoring for compliance with...) Recordkeeping activities. Elevator and merchandising recordkeeping activities subject to monitoring...

  16. Surface deformation of active volcanic areas retrieved with the SBAS-DInSAR technique: an overview

    Directory of Open Access Journals (Sweden)

    G. Zeni

    2008-06-01

    Full Text Available This paper presents a comprehensive overview of the surface deformation retrieval capability of the Differential Synthetic Aperture Radar Interferometry (DInSAR algorithm, referred to as Small BAseline Subset (SBAS technique, in the context of active volcanic areas. In particular, after a brief description of the algorithm some experiments relevant to three selected case-study areas are presented. First, we concentrate on the application of the SBAS algorithm to a single-orbit scenario, thus considering a set of SAR data composed by images acquired on descending orbits by the European Remote Sensing (ERS radar sensors and relevant to the Long Valley caldera (eastern California area. Subsequently, we address the capability of the SBAS technique in a multipleorbit context by referring to Mt. Etna volcano (southern Italy test site, with respect to which two different ERS data set, composed by images acquired both on ascending and descending orbits, are available. Finally, we take advantage of the capability of the algorithm to work in a multi-platform scenario by jointly exploiting two different sets of SAR images collected by the ERS and the Environment Satellite (ENVISAT radar sensors in the Campi Flegrei caldera (southern Italy area. The presented results demonstrate the effectiveness of the algorithm to investigate the deformation field in active volcanic areas and the potential of the DInSAR methodologies within routine surveillance scenario.

  17. Subsurface combustion in Mali: Refutation of the active volcanism hypothesis in West Africa

    Science.gov (United States)

    Svensen, Henrik; Dysthe, Dag Kristian; Bandlien, Einar H.; Sacko, Samba; Coulibaly, Henri; Planke, Sverre

    2003-07-01

    Surface heat anomalies have been known in the Timbuktu region in northern Mali for more than a century. Since about 1960, several authors have argued that these heat anomalies are caused by incipient volcanic and hydrothermal activity. Surface temperatures as high as 765 °C were measured locally in January 2002, and smoke emanated from holes and fractures in the ground. We demonstrate that subsurface combustion of organic material is the source of the heat and the gases. Several square kilometers are currently active or have been affected by subsurface fires since 2001. Self-ignition during biological degradation of organic-rich layers in the lacustrine deposits is the most likely mechanism that started the subsurface combustion that caused the heat anomalies in the area. An important consequence of this conclusion is that West Africa should still be regarded as volcanologically inactive, and that possible reactivations of the major EW-trending Guinean-Nubian lineament are not associated with volcanism. We suggest that the subsurface combustion in the Timbuktu region today represents a phenomenon with a very long record in the Trans-Saharan region.

  18. Connecting Io's volcanic activity to the Io plasma torus: comparison of Galileo/NIMS volcanic and ground-based torus observations

    Science.gov (United States)

    Magalhaes, F. P.; Lopes, R. M. C.; Rathbun, J. A.; Gonzalez, W. D.; Morgenthaler, J. P.; Echer, E.; Echer, M. P. D. S.

    2015-12-01

    Io, the innermost of the Jupiter's four Galilean moons, is a remarkable object in the Solar System, due to its intense and energetic volcanic activity. The volcanic sulfur and oxygen in Io's tenuous atmosphere escapes forming an extended neutral cloud around Io and Jupiter. Subsequently, by ionization and pickup ions, a ring of charged particles encircling Jupiter is created, forming the Io plasma torus. Considering this scenario, it is reasonable to expect that the Io plasma torus should be affected by changes in Io's volcanism. Interactions between Io and the Jovian environment is unique and yet not very well understood. Here we present two sets of observations. One from the Galileo Near-Infrared Imaging Spectrograph (NIMS) instrument, which obtained spectral image cubes between 0.7 and 5.2 microns. The other dataset is from ground-based observations of the [SII] 6731 Å emission lines from the Io plasma torus, obtained at McMath-Pierce Solar Telescope, at Kitt Peak. Our dataset from the [SII] 6731 Å emission lines cover more years than the one from the NIMS data. The years presented in this work for a comparative study are from 1998 through 2001. Using the NIMS instrument we were able to identify which volcanoes were active and measure their level of activity. From the [SII] 6731 Å emission lines we were able to trace the densest part of the torus and also the brightness of both ansa. By comparing the results from the Galileo instrument and the ground-based observations, we are exploring how the Io plasma torus responds to large eruptions from Io. We aim with this study to help improve our understanding of this complex coupled system, Jupiter-Io.

  19. Characteristics of volcanic gas correlated to the eruption activity; Case study in the Merapi Volcano, periods of 1990-1994

    Directory of Open Access Journals (Sweden)

    Priatna Priatna

    2014-06-01

    Full Text Available http://dx.doi.org/10.17014/ijog.vol2no4.20074Volcanic gases, collected from Gendol and Woro solfatara fields, the summit of Merapi Volcano during 1990-1994, show an increase in chemical composition of H , CO, CO , SO , and HCl prior to the volcanic events, on the contrary to the drastic decreasing water vapour. The carbon/sulfur ratio of the volcanic gases lies between 1.5 and 5.7 which means that they were derived from the fresh magma. The Apparent Equilibrium Temperature (AET which is calculated from chemical compositions of volcanic gases using reaction of SO +3H = H S+2H O showed an increasing value prior to the volcanic events. The Merapi activities lasted during August 1990 to November 1994 showed a significant increase in ratio SO /H S prior to the November 1994 pyroclastic flow. The isotopic composition of volcanic gas condensates indicates that water vapour in Gendol is directly derived from the fresh magma. On the other hand, the contamination and cooling by the subsurface water occurred around the Woro field at a shallow part. 

  20. Understanding causality and uncertainty in volcanic observations: An example of forecasting eruptive activity on Soufrière Hills Volcano, Montserrat

    Science.gov (United States)

    Sheldrake, T. E.; Aspinall, W. P.; Odbert, H. M.; Wadge, G.; Sparks, R. S. J.

    2017-07-01

    Following a cessation in eruptive activity it is important to understand how a volcano will behave in the future and when it may next erupt. Such an assessment can be based on the volcano's long-term pattern of behaviour and insights into its current state via monitoring observations. We present a Bayesian network that integrates these two strands of evidence to forecast future eruptive scenarios using expert elicitation. The Bayesian approach provides a framework to quantify the magmatic causes in terms of volcanic effects (i.e., eruption and unrest). In October 2013, an expert elicitation was performed to populate a Bayesian network designed to help forecast future eruptive (in-)activity at Soufrière Hills Volcano. The Bayesian network was devised to assess the state of the shallow magmatic system, as a means to forecast the future eruptive activity in the context of the long-term behaviour at similar dome-building volcanoes. The findings highlight coherence amongst experts when interpreting the current behaviour of the volcano, but reveal considerable ambiguity when relating this to longer patterns of volcanism at dome-building volcanoes, as a class. By asking questions in terms of magmatic causes, the Bayesian approach highlights the importance of using short-term unrest indicators from monitoring data as evidence in long-term forecasts at volcanoes. Furthermore, it highlights potential biases in the judgements of volcanologists and identifies sources of uncertainty in terms of magmatic causes rather than scenario-based outcomes.

  1. Methods of InSAR atmosphere correction for volcano activity monitoring

    Science.gov (United States)

    Gong, W.; Meyer, F.; Webley, P.W.; Lu, Zhiming

    2011-01-01

    When a Synthetic Aperture Radar (SAR) signal propagates through the atmosphere on its path to and from the sensor, it is inevitably affected by atmospheric effects. In particular, the applicability and accuracy of Interferometric SAR (InSAR) techniques for volcano monitoring is limited by atmospheric path delays. Therefore, atmospheric correction of interferograms is required to improve the performance of InSAR for detecting volcanic activity, especially in order to advance its ability to detect subtle pre-eruptive changes in deformation dynamics. In this paper, we focus on InSAR tropospheric mitigation methods and their performance in volcano deformation monitoring. Our study areas include Okmok volcano and Unimak Island located in the eastern Aleutians, AK. We explore two methods to mitigate atmospheric artifacts, namely the numerical weather model simulation and the atmospheric filtering using Persistent Scatterer processing. We investigate the capability of the proposed methods, and investigate their limitations and advantages when applied to determine volcanic processes. ?? 2011 IEEE.

  2. Subsurface Fires in Mali: Refutation of Active Volcanism Hypothesis in West-Central Africa

    Science.gov (United States)

    Bandlien, E. H.; Svensen, H.; Dysthe, D. K.; Planke, S.

    2002-12-01

    Surface heat anomalies have been known in the Lac Faguibine area in Northern Mali for more than a century. Several authors have the last 40 years argued that that these heat anomalies are caused by incipient volcanic and hydrothermal activity. Fieldwork in the Lac Faguibine area in January 2002 focused on four regions where smoke emanated from holes and fractures in lacustrine sediments. Surface temperatures as high as 730 °C were measured locally. At one locality, the temperature anomalies formed a laterally migrating front defined by fractured and heated sediments. A trench was dug into the temperature front to determine the cause of the heat and smoke emanations. A 0.7 meter thick slowly combusting organic-rich layer (8 wt. % organic carbon) was discovered below a 0.5-meter thick surface layer of diatomitic siltstone. The siltstone was actively metamorphosed by oxidation from gray to red. At another locality, an expanding circular area of subsurface combustion strongly affected the vegetation. Smoke emanated from fractures, combusted root networks and holes with a diameter up to 0.5 meter. Some of the holes were gloving, indicating a shallow combustion of organic material. The combustion released CO2 and H2O vapor, and minerals like salammoniac, ammonium hydrogen sulfate and native sulfur have precipitated at the surface. Several square kilometers large areas are currently combusting, or have been affected by subsurface fires since 2001. In addition, areas with red deformed diatomitic siltstone in the Lac Faguibine region suggest that subsurface combustion within the lacustrine sediments have had an important regional ecological effect. The most likely mechanism for starting the subsurface combustion is self-ignition during biological degradation of organic rich layers in the lacustrine deposits. Shallow lakes, similar to the Lac Faguibine, were abundant in the Trans-Saharan region during the Holocene, but evaporated during global climate changes about 4500 B

  3. Diffuse CO2 emission from the NE volcanic rift-zone of Tenerife (Canary Islands, Spain): a 15 years geochemical monitoring

    Science.gov (United States)

    Padilla, Germán; Alonso, Mar; Shoemaker, Trevor; Loisel, Ariane; Padrón, Eleazar; Hernández, Pedro A.; Pérez, Nemesio M.

    2016-04-01

    The North East Rift (NER) volcanic zone of Tenerife Island is one of the three volcanic rift-zones of the island (210 km2). The most recent eruptive activity along the NER volcanic zone took place in the 1704-1705 period with the volcanic eruptions of Siete Fuentes, Fasnia and Arafo volcanoes. The aim of this study was to report the results of a soil CO2 efflux survey undertaken in June 2015, with approximately 580 measuring sites. In-situ measurements of CO2 efflux from the surface environment of NER volcanic zone were performed by means of a portable non-dispersive infrared spectrophotometer (NDIR) model LICOR Li800 following the accumulation chamber method. To quantify the total CO2 emission from NER volcanic zone, soil CO2 efflux contour maps were constructed using sequential Gaussian simulation (sGs) as interpolation method. The total diffuse CO2 emission rate was estimated in 1209 t d-1, with CO2 efflux values ranging from non-detectable (˜0.5 g m-2 d-1) up to 123 g m-2 d-1, with an average value of 5.9 g m-2 d-1. If we compare these results with those obtained in previous surveys developed in a yearly basis, they reveal slightly variations from 2006 to 2015, with to pulses in the CO2 emission observed in 2007 and 2014. The main temporal variation in the total CO2 output does not seem to be masked by external variations. First peak precedes the anomalous seismicity registered in and around Tenerife Island between 2009 and 2011, suggesting stress-strain changes at depth as a possible cause for the observed changes in the total output of diffuse CO2 emission. Second peak could be related with futures changes in the seismicity. This study demonstrates the importance of performing soil CO2 efflux surveys as an effective surveillance volcanic tool.

  4. The 2011 volcanic crisis at El Hierro (Canary Islands): monitoring ground deformation through tiltmeter and gravimetric observations

    Science.gov (United States)

    Arnoso, J.; Montesinos, F. G.; Benavent, M.; Vélez, E. J.

    2012-04-01

    El Hierro is an ocean island located at the western end of the Canary Islands, and along with Tenerife and La Palma islands have been the most geologically active in the recent past. The island has a triple armed rift and, presently, is at the stage of growth, representing the summit of a volcanic shield elevating from the seafloor at depth of 4000 m up to 1501 m above the sea level (Münn et al., 2006; Carracedo et al., 1999). Since July 19th, 2011 seismic activity has produced more than 11950 events up to date. The seismic crisis resulted in a volcanic eruption that began on October 10th, being still currently active. The new volcano is located 2 km off the coast and about 300 m depth, in the submarine flank of the southern rift of the island, which is extended some 40 km length. Since September 2004 until November 2010 two continuous tilt stations were installed at the north, Balneario site (BA), and at the center of the island, Aula de la Naturaleza (AU) site. Both stations were used to assess the pattern of local ground movements in the island. When seismic swarm started on past July 2011, we have reinstalled both tilt stations (BA and AU) and 2 new ones located at the south of the island, namely Montaña Quemada (MQ) and Restinga (RE) sites. We have used short base platform tiltmeters that measure ground tilts with resolutions varying from 0.1 up to 0.01 microradians (µrad). On October 8th, a 4.4 magnitude earthquake took place and is supposed that fractured the ocean crust at some 8-10 km off the south coast of the island and about 1000 m depth. Typical spike signals were observed at the tilt stations. Two days after, the eruption onset was recorded also at tilt stations through a remarkable increase of the high frequency signal, being of large amplitude the components (radial) orientated towards the new volcano edifice. When compared with previous tiltmeter records in the island, tilt pattern were clearly modified several times at the stations when strong

  5. Aspects of historical eruptive activity and volcanic unrest at Mt. Tongariro, New Zealand: 1846-2013

    Science.gov (United States)

    Scott, Bradley J.; Potter, Sally H.

    2014-10-01

    The 6 August and 21 November 2012 eruptions from Upper Te Maari crater have heightened interest in past activity at Mt. Tongariro, New Zealand. Risks caused by volcanic hazards are increasingly being quantified by using probability estimates through expert elicitation, partly based on the frequency of past eruptions. To maximise the accuracy of these risk values at Mt. Tongariro, a historical eruption catalogue is required. This paper presents the findings of a detailed historical chronology of unrest and eruptions at Mt. Tongariro between 1846 AD and 2013 AD. It builds on the findings of previous researchers, highlighting that volcanic eruptions and unrest have occurred frequently from this volcano. Eruptions are now thought to have occurred at Mt. Tongariro in 1869, 1892, 1896-97, 1899, 1926, 1927, 1934 and 2012. Eruptions also potentially occurred in 1846, 1855, 1886, and 1928, in addition to frequent eruptions from neighbouring Mt. Ngauruhoe. The number of recognised eruptions during the 1896-97 episode has increased to 18, and the Red Crater area has been found to be more active than previously appreciated. Multiple episodes of unrest not resulting in eruptions have also been identified. New eruption recurrence rates are derived from this catalogue, with the baseline probability of the onset of an eruption episode calculated to be 0.07 per year (if 1896-97 and 2012 are considered as one episode each, and all others separately), and the maximum eruption rate within an eruption episode is 18 per year. These new data contribute towards risk assessments for future eruptions at Mt. Tongariro.

  6. Monitoring Biological Activity at Geothermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Peter Pryfogle

    2005-09-01

    The economic impact of microbial growth in geothermal power plants has been estimated to be as high as $500,000 annually for a 100 MWe plant. Many methods are available to monitor biological activity at these facilities; however, very few plants have any on-line monitoring program in place. Metal coupon, selective culturing (MPN), total organic carbon (TOC), adenosine triphosphate (ATP), respirometry, phospholipid fatty acid (PLFA), and denaturing gradient gel electrophoresis (DGGE) characterizations have been conducted using water samples collected from geothermal plants located in California and Utah. In addition, the on-line performance of a commercial electrochemical monitor, the BIoGEORGE?, has been evaluated during extended deployments at geothermal facilities. This report provides a review of these techniques, presents data on their application from laboratory and field studies, and discusses their value in characterizing and monitoring biological activities at geothermal power plants.

  7. Chemical evolution at the coasts of active volcanic islands in a primordial salty ocean

    Science.gov (United States)

    Strasdeit, H.; Fox, S.

    2008-09-01

    The Prebiotic Hot-Volcanic-Coast Scenario It has been suggested that in the Hadean eon (4.5-3.8 Ga before present) no permanent continents but volcanic islands and short-lived protocontinents protruded from the first ocean [1, 2]. As the geothermal heat production was considerably higher than today, it is reasonable to assume that hot volcanic coasts were much more abundant. The salinity of the ocean was probably up to two times higher than the modern value [3]. Under these conditions, the evaporation of seawater at active volcanic coasts must have produced sea salt crusts - a process that can still be observed today [4]. On the hot lava rock, the salt crusts can subsequently experience temperatures up to some hundred degrees Celsius. The seawater probably contained abiotically formed organic molecules such as amino acids, which were inevitably embedded into the sea salt crusts. Different prebiotic sources of amino acids have been discussed: (i) comets and meteorites [5], electrical discharges in the atmosphere [6, 7], and deep-sea hydrothermal vents [8]. We undertook a systematic study of solid salt-amino acid mixtures, especially of their formation and thermal behavior under simulated conditions of the hotvolcanic- coast scenario. Laboratory Experiments Amino acids@salts Artificial Hadean seawater was prepared by dissolving NaCl (705 mmol), MgCl2 (80 mmol), KCl (15 mmol), CaCl2 (15 mmol), and an α-amino acid (5-10 mmol) or a mixture of α-amino acids. In order to model the first step of the hot-volcanic-coast scenario, the solutions were evaporated to dryness. Vibrational spectroscopy (IR, Raman) and X-ray powder diffraction showed that the resulting solid residues were not heterogeneous mixtures of salt and amino acid crystals. Instead the amino acid molecules were coordinated in calcium or magnesium complexes. We have studied the rac-alanine ( + H3NCH(CH3)COO -, Hala) system in more detail and found that the complex that is present in the mixture has the

  8. Recent and episodic volcanic and glacial activity on Mars revealed by the High Resolution Stereo Camera.

    Science.gov (United States)

    Neukum, G; Jaumann, R; Hoffmann, H; Hauber, E; Head, J W; Basilevsky, A T; Ivanov, B A; Werner, S C; van Gasselt, S; Murray, J B; McCord, T

    2004-12-23

    The large-area coverage at a resolution of 10-20 metres per pixel in colour and three dimensions with the High Resolution Stereo Camera Experiment on the European Space Agency Mars Express Mission has made it possible to study the time-stratigraphic relationships of volcanic and glacial structures in unprecedented detail and give insight into the geological evolution of Mars. Here we show that calderas on five major volcanoes on Mars have undergone repeated activation and resurfacing during the last 20 per cent of martian history, with phases of activity as young as two million years, suggesting that the volcanoes are potentially still active today. Glacial deposits at the base of the Olympus Mons escarpment show evidence for repeated phases of activity as recently as about four million years ago. Morphological evidence is found that snow and ice deposition on the Olympus construct at elevations of more than 7,000 metres led to episodes of glacial activity at this height. Even now, water ice protected by an insulating layer of dust may be present at high altitudes on Olympus Mons.

  9. Impact of volcanic fluoride and SO/sub 7/ emissions from moderated activity volcanoes on the surrounding vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Garrec, J.P.; Plebin, R.; Faivre-Pierret, R.X.

    1984-01-01

    Studies in the regions of the volcanoes Etna (Italy) and Masaya (Nicaragua) show that the continuous emissions of gaseous pollutants (HF and SO/sub 2/) from moderated activity volcanoes causes a chronic pollution in the surrounding vegetation with certain economical and ecological consequences. Reciprocally the measure of the pollutants in the plants growing in volcanic regions may be a simple and fast method to investigate some characteristics of the volcanic plume: for example, intensity of the emissions of gas, direction and extent of the plume. 12 references.

  10. Technology of remote monitoring for nuclear activity monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Kwack, Ehn Ho; Kim, Jong Soo; Yoon, Wan Ki; Park, Sung Sik; Na, Won Woo; An, Jin Soo; Cha, Hong Ryul; Kim, Jung Soo

    2000-05-01

    In a view of safeguards monitoring at nuclear facilities, the monitoring is changing to remote method so that this report is described to remote monitoring(RM) applying on commercial NPP in Korea. To enhance IAEA safeguards efficiency and effectiveness, IAEA is taking into account of remote monitoring system(RMS) and testing as a field trial. IRMP(International Remote Monitoring Project) in participating many nations for development of RMS is proceeding their project such as technical exchange and research etc. In case of our country are carrying out the research relevant RM since acceptance RMS at 7th ROK-IAEA safeguards implementation review meeting. With a view to enhancement the RMS, installation location and element technology of the RM equipment are evaluated in a view of safeguards in Korea LWRs, and proposed a procedure for national inspection application through remote data evaluation from Younggwang-3 NPP. These results are large valuable to use of national inspection at time point extending installation to all Korea PWR NPP. In case of CANDU, neutron, gamma measurement and basic concept of network using optical fiber scintillating detector as remote verification method for dry storage canister are described. Also RM basic design of spent fuel transfer campaign is described that unattended RM without inspector instead of performing in participating together with IAEA and national inspector. The transfer campaign means the spent fuel storage pond to dry storage canister for about two months every year. Therefore, positively participation of IAEA strength safeguards project will be increased transparency for our nuclear activity as well as contributed to national relevant industry.

  11. Volcanic gas

    Science.gov (United States)

    McGee, Kenneth A.; Gerlach, Terrance M.

    1995-01-01

    In Roman mythology, Vulcan, the god of fire, was said to have made tools and weapons for the other gods in his workshop at Olympus. Throughout history, volcanoes have frequently been identified with Vulcan and other mythological figures. Scientists now know that the “smoke" from volcanoes, once attributed by poets to be from Vulcan’s forge, is actually volcanic gas naturally released from both active and many inactive volcanoes. The molten rock, or magma, that lies beneath volcanoes and fuels eruptions, contains abundant gases that are released to the surface before, during, and after eruptions. These gases range from relatively benign low-temperature steam to thick hot clouds of choking sulfurous fume jetting from the earth. Water vapor is typically the most abundant volcanic gas, followed by carbon dioxide and sulfur dioxide. Other volcanic gases are hydrogen sulfide, hydrochloric acid, hydrogen, carbon monoxide, hydrofluoric acid, and other trace gases and volatile metals. The concentrations of these gas species can vary considerably from one volcano to the next.

  12. Understanding Hydrological and Climate Conditions on Early Mars Through Sulfate Cycling and Microbial Activity in Terrestrial Volcanic Systems

    Science.gov (United States)

    Szynkiewicz, A.; Mikucki, J.; Vaniman, D.

    2017-10-01

    Our study is a type of Earth-based investigation in a Mars-analog environment that allows for determination of how changing wet and dry conditions in active volcanic/hydrothermal system affect sulfate fluxes into surface water and groundwater.

  13. Unraveling the Lipolytic Activity of Thermophilic Bacteria Isolated from a Volcanic Environment

    Directory of Open Access Journals (Sweden)

    Panagiota M. Stathopoulou

    2013-01-01

    Full Text Available In a bioprospecting effort towards novel thermostable lipases, we assessed the lipolytic profile of 101 bacterial strains isolated from the volcanic area of Santorini, Aegean Sea, Greece. Screening of lipase activity was performed both in agar plates and liquid cultures using olive oil as carbon source. Significant differences were observed between the two screening methods with no clear correlation between them. While the percentage of lipase producing strains identified in agar plates was only 17%, lipolytic activity in liquid culture supernatants was detected for 74% of them. Nine strains exhibiting elevated extracellular lipase activities were selected for lipase production and biochemical characterization. The majority of lipase producers revealed high phylogenetic similarity with Geobacillus species and related genera, whilst one of them was identified as Aneurinibacillus sp. Lipase biosynthesis strongly depended on the carbon source that supplemented the culture medium. Olive oil induced lipase production in all strains, but maximum enzyme yields for some of the strains were also obtained with Tween-80, mineral oil, and glycerol. Partially purified lipases revealed optimal activity at 70–80°C and pH 8-9. Extensive thermal stability studies revealed marked thermostability for the majority of the lipases as well as a two-step thermal deactivation pattern.

  14. Aerial monitoring in active mud volcano by UAV technique

    Science.gov (United States)

    Pisciotta, Antonino; Capasso, Giorgio; Madonia, Paolo

    2016-04-01

    UAV photogrammetry opens various new applications in the close range domain, combining aerial and terrestrial photogrammetry, but also introduces low-cost alternatives to the classical manned aerial photogrammetry. Between 2014 and 2015 tree aerial surveys have been carried out. Using a quadrotor drone, equipped with a compact camera, it was possible to generate high resolution elevation models and orthoimages of The "Salinelle", an active mud volcanoes area, located in territory of Paternò (South Italy). The main risks are related to the damages produced by paroxysmal events. Mud volcanoes show different cyclic phases of activity, including catastrophic events and periods of relative quiescence characterized by moderate activity. Ejected materials often are a mud slurry of fine solids suspended in liquids which may include water and hydrocarbon fluids, the bulk of released gases are carbon dioxide, with some methane and nitrogen, usually pond-shaped of variable dimension (from centimeters to meters in diameter). The scope of the presented work is the performance evaluation of a UAV system that was built to rapidly and autonomously acquire mobile three-dimensional (3D) mapping data in a volcanic monitoring scenario.

  15. Performance evaluation of salivary amylase activity monitor.

    Science.gov (United States)

    Yamaguchi, Masaki; Kanemori, Takahiro; Kanemaru, Masashi; Takai, Noriyasu; Mizuno, Yasufumi; Yoshida, Hiroshi

    2004-10-15

    In order to quantify psychological stress and to distinguish eustress and distress, we have been investigating the establishment of a method that can quantify salivary amylase activity (SMA). Salivary glands not only act as amplifiers of a low level of norepinephrine, but also respond more quickly and sensitively to psychological stress than cortisol levels. Moreover, the time-course changes of the salivary amylase activity have a possibility to distinguish eustress and distress. Thus, salivary amylase activity can be utilized as an excellent index for psychological stress. However, in dry chemistry system, a method for quantification of the enzymatic activity still needs to be established that can provide with sufficient substrate in a testing tape as well as can control enzymatic reaction time. Moreover, it is necessary to develop a method that has the advantages of using saliva, such as ease of collection, rapidity of response, and able to use at any time. In order to establish an easy method to monitor the salivary amylase activity, a salivary transcription device was fabricated to control the enzymatic reaction time. A fabricated salivary amylase activity monitor consisted of three devices, the salivary transcription device, a testing-strip and an optical analyzer. By adding maltose as a competitive inhibitor to a substrate Ga1-G2-CNP, a broad-range activity testing-strip was fabricated that could measure the salivary amylase activity with a range of 0-200 kU/l within 150 s. The calibration curve of the monitor for the salivary amylase activity showed R2=0.941, indicating that it was possible to use this monitor for the analysis of the salivary amylase activity without the need to determine the salivary volume quantitatively. In order to evaluate the assay variability of the monitor, salivary amylase activity was measured using Kraepelin psychodiagnostic test as a psychological stressor. A significant difference of salivary amylase activity was recognized

  16. California GAMA Program: Groundwater Ambient Monitoring and Assessment Results for the Sacramento Valley and Volcanic Provinces of Northern California

    Energy Technology Data Exchange (ETDEWEB)

    Moran, J E; Hudson, G B; Eaton, G F; Leif, R

    2005-01-20

    In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as methyl tert butyl ether (MTBE) from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater monitoring plan, and led to the initiation of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The primary objective of the California Aquifer Susceptibility (CAS) project (under the GAMA Program) is to assess water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey, the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement this groundwater assessment program. In 2003, LLNL carried out this vulnerability study in the Sacramento Valley and Volcanic Provinces. The goal of the study is to provide a probabilistic assessment of the relative vulnerability of groundwater used for the public water supply to contamination from surface sources. This assessment of relative contamination vulnerability is made based on the results of two types of analyses that are not routinely carried out at public water supply wells: ultra low-level measurement of volatile organic compounds (VOCs), and groundwater age dating (using the tritium-helium-3 method). In addition, stable oxygen isotope measurements

  17. Methanotrophic activity and diversity of methanotrophs in volcanic geothermal soils at Pantelleria (Italy)

    Science.gov (United States)

    Gagliano, A. L.; D'Alessandro, W.; Tagliavia, M.; Parello, F.; Quatrini, P.

    2014-10-01

    Volcanic and geothermal systems emit endogenous gases by widespread degassing from soils, including CH4, a greenhouse gas twenty-five times as potent as CO2. Recently, it has been demonstrated that volcanic or geothermal soils are not only a source of methane, but are also sites of methanotrophic activity. Methanotrophs are able to consume 10-40 Tg of CH4 a-1 and to trap more than 50% of the methane degassing through the soils. We report on methane microbial oxidation in the geothermally most active site of Pantelleria (Italy), Favara Grande, whose total methane emission was previously estimated at about 2.5 Mg a-1 (t a-1). Laboratory incubation experiments with three top-soil samples from Favara Grande indicated methane consumption values of up to 59.2 nmol g-1 soil d.w. h-1. One of the three sites, FAV2, where the highest oxidation rate was detected, was further analysed on a vertical soil profile, the maximum methane consumption was measured in the top-soil layer, and values greater than 6.23 nmol g-1 h-1 were still detected up to a depth of 13 cm. The highest consumption rate was measured at 37 °C, but a still detectable consumption at 80 °C (> 1.25 nmol g-1 h-1) was recorded. The soil total DNA extracted from the three samples was probed by Polymerase Chain Reaction (PCR) using standard proteobacterial primers and newly designed verrucomicrobial primers, targeting the unique methane monooxygenase gene pmoA; the presence of methanotrophs was detected at sites FAV2 and FAV3, but not at FAV1, where harsher chemical-physical conditions and negligible methane oxidation were detected. The pmoA gene libraries from the most active site (FAV2) pointed to a high diversity of gammaproteobacterial methanotrophs, distantly related to Methylocaldum-Metylococcus genera, and the presence of the newly discovered acido-thermophilic Verrucomicrobia methanotrophs. Alphaproteobacteria of the genus Methylocystis were isolated from enrichment cultures under a methane

  18. Methanotrophic activity and bacterial diversity in volcanic-geothermal soils at Pantelleria island (Italy)

    Science.gov (United States)

    Gagliano, A. L.; D'Alessandro, W.; Tagliavia, M.; Parello, F.; Quatrini, P.

    2014-04-01

    Volcanic and geothermal systems emit endogenous gases by widespread degassing from soils, including CH4, a greenhouse gas twenty-five times as potent as CO2. Recently, it has been demonstrated that volcanic/geothermal soils are source of methane, but also sites of methanotrophic activity. Methanotrophs are able to consume 10-40 Tg of CH4 a-1 and to trap more than 50% of the methane degassing through the soils. We report on methane microbial oxidation in the geothermally most active site of Pantelleria island (Italy), Favara Grande, whose total methane emission was previously estimated in about 2.5 t a-1. Laboratory incubation experiments with three top-soil samples from Favara Grande indicated methane consumption values up to 950 ng g-1 dry soil h-1. One of the three sites, FAV2, where the highest oxidation rate was detected, was further analysed on a vertical soil profile and the maximum methane consumption was measured in the top-soil layer but values > 100 ng g-1 h-1 were maintained up to a depth of 15 cm. The highest consumption rate was measured at 37 °C, but a still recognizable consumption at 80 °C (> 20 ng g-1 h-1) was recorded. In order to estimate the bacterial diversity, total soil DNA was extracted from Favara Grande and analysed using a Temporal Temperature Gradient gel Electrophoresis (TTGE) analysis of the amplified bacterial 16S rRNA gene. The three soil samples were probed by PCR using standard proteobacterial primers and newly designed verrucomicrobial primers targeting the unique methane monooxygenase gene pmoA; the presence of methanotrophs was detected in sites FAV2 and FAV3, but not in FAV1, where harsher chemical-physical conditions and negligible methane oxidation were detected. The pmoA gene libraries from the most active site FAV2 pointed out a high diversity of gammaproteobacterial methanotrophs distantly related to Methylococcus/Methylothermus genera and the presence of the newly discovered acido-thermophilic methanotrophs

  19. Influence of explosive volcanic events on the activation versus de-activation of a modern turbidite system: the example of the Dohrn canyon-fan in the continental slope of the Campania volcanic district (Naples Bay, Italy - Western Mediterranean)

    Science.gov (United States)

    Roca, M.; Budillon, F.; Pappone, G.; Insinga, D.

    2015-12-01

    The interplay between volcanic activity, volcano-clastic yield and activation/deactivation of a turbidite system can be evaluated along the continental margin of Campania region (Tyrrhenian Sea - Italy), an active volcanic area, where three wide canyon-fans occur at short distances one to another. Actually, the Dohrn, Magnaghi and Cuma canyons cut the continental slope and shelf off Ischia and Procida volcanic islands and off the Campania Plain where Phlegraean Field and Mt. Vesuvius active vents are located. This research, partly supported by the Italian Flagship Project Ritmare, is based on single-channel, high-resolution seismic profiles (Sparker-One 16 kJ, 0.5 s twtt), swath-bathymetry and litho- and tephra-stratigraphy of gravity cores. We focused on the stratigraphic constraint of paleo-thalweg features and channel/levees deposits in seismics, debris flow, turbidites and hemipelagites in cores, to learn more on the activation/deactivation stages of the canyon Dohrn, in the frame of relative eustatic sea level variations over the Middle Pleistocene-Holocene time span.Preliminary outcomes suggest that even major volcanic events occurred in the last 300 ky, such as ignimbrite eruptions or large fallouts, have caused the infilling of the canyon head and the cover of pre-existing seabed morphology. As a consequence, the temporary deactivation of the turbidite system has occurred, despite the volcano-clastic overload in the coastal environment. Phases of renewed activities of the thalweg are observed to be in step with falling stages of sea level, which have driven the re-incision of canyon valleys through continuous volcano-clastic debris and turbidites down-flows. Since Holocene, the quiescence of the Dohrn Canyon has been documented, despite the intense volcano-tectonic activity in the area.

  20. Acute health effects associated with exposure to volcanic air pollution (vog) from increased activity at Kilauea Volcano in 2008.

    Science.gov (United States)

    Longo, Bernadette M; Yang, Wei; Green, Joshua B; Crosby, Frederick L; Crosby, Vickie L

    2010-01-01

    In 2008, the Kilauea Volcano on the island of Hawai'i increased eruption activity and emissions of sulfurous volcanic air pollution called vog. The purpose of this study was to promptly assess for a relative increase in cases of medically diagnosed acute illnesses in an exposed Hawaiian community. Using a within-clinic retrospective cohort design, comparisons were made for visits of acute illnesses during the 14 wk prior to the increased volcanic emissions (low exposure) to 14 wk of high vog exposure when ambient sulfur dioxide was threefold higher and averaged 75 parts per billion volume per day. Logistic regression analysis estimated effect measures between the low- and high-exposure cohorts for age, gender, race, and smoking status. There were statistically significant positive associations between high vog exposure and visits for medically diagnosed cough, headache, acute pharyngitis, and acute airway problems. More than a sixfold increase in odds was estimated for visits with acute airway problems, primarily experienced by young Pacific Islanders. These findings suggest that the elevated volcanic emissions in 2008 were associated with increased morbidity of acute illnesses in age and racial subgroups of the general Hawaiian population. Continued investigation is crucial to fully assess the health impact of this natural source of sulfurous air pollution. Culturally appropriate primary- and secondary-level health prevention initiatives are recommended for populations in Hawai'i and volcanically active areas worldwide.

  1. Active system monitoring applied on wind turbines

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad; Parbo, Henrik

    2009-01-01

    A concept for active system monitoring (ASM) applied on wind turbines is presented in this paper. The concept is based on an injection of a small periodic auxiliary signal in the system. An investigation of the signature from the auxiliary input in residual (error) signals can then be applied...

  2. Stress fields of the overriding plate at convergent margins and beneath active volcanic arcs.

    Science.gov (United States)

    Apperson, K D

    1991-11-01

    Tectonic stress fields in the overriding plate at convergent plate margins are complex and vary on local to regional scales. Volcanic arcs are a common element of overriding plates. Stress fields in the volcanic arc region are related to deformation generated by subduction and to magma generation and ascent processes. Analysis of moment tensors of shallow and intermediate depth earthquakes in volcanic arcs indicates that the seismic strain field in the arc region of many convergent margins is subhorizontal extension oriented nearly perpendicular to the arc. A process capable of generating such a globally consistent strain field is induced asthenospheric corner flow below the arc region.

  3. Experimental generation of volcanic lightning

    Science.gov (United States)

    Cimarelli, Corrado; Alatorre-Ibargüengoitia, Miguel; Kueppers, Ulrich; Scheu, Bettina; Dingwell, Donald B.

    2014-05-01

    Ash-rich volcanic plumes that are responsible for injecting large quantities of aerosols into the atmosphere are often associated with intense electrical activity. Direct measurement of the electric potential at the crater, where the electric activity in the volcanic plume is first observed, is severely impeded, limiting progress in its investigation. We have achieved volcanic lightning in the laboratory during rapid decompression experiments of gas-particle mixtures under controlled conditions. Upon decompression (from ~100 bar argon pressure to atmospheric pressure), loose particles are vertically accelerated and ejected through a nozzle of 2.8 cm diameter into a large tank filled with air at atmospheric conditions. Because of their impulsive character, our experiments most closely represent the conditions encountered in the gas-thrust region of the plume, when ash is first ejected from the crater. We used sieved natural ash with different grain sizes from Popocatépetl (Mexico), Eyjafjallajökull (Iceland), and Soufrière Hills (Montserrat) volcanoes, as well as micrometric glass beads to constrain the influence of material properties on lightning. We monitored the dynamics of the particle-laden jets with a high-speed camera and the pressure and electric potential at the nozzle using a pressure transducer and two copper ring antennas connected to a high-impedance data acquisition system, respectively. We find that lightning is controlled by the dynamics of the particle-laden jet and by the abundance of fine particles. Two main conditions are required to generate lightning: 1) self-electrification of the particles and 2) clustering of the particles driven by the jet fluid dynamics. The relative movement of clusters of charged particles within the plume generates the gradient in electrical potential, which is necessary for lightning. In this manner it is the gas-particle dynamics together with the evolving particle-density distribution within different regions of

  4. The 2011-2012 unrest at Santorini rift: Stress interaction between active faulting and volcanism

    Science.gov (United States)

    Feuillet, Nathalie

    2013-07-01

    Santorini, active normal faulting controls the emission of volcanic products. Such geometry has implication on seismic activity around the plumbing system during unrest. Static Coulomb stress changes induced by the 2011-2012 inflation within a preexisting NW-SE extensional regional stress field, compatible with fault geometry, increased by more than 0.5 MPa in an ellipsoid-shaped zone beneath the Minoan caldera where almost all earthquakes (96%) have occurred since beginning of unrest. Magmatic processes perturb the regional stress in the caldera where strike-slip rather than normal faulting along NE-SW striking planes are expected. The inflation may have also promoted more distant moderate earthquakes on neighboring faults as the M > 5 January 2012, south of Christiania. Santorini belongs to a set of en echelon NE-SW striking rifts (Milos, Nysiros) oblique to the Aegean arc that may have initiated in the Quaternary due to propagation of the North Anatolian fault into the Southern Aegean Sea.

  5. Relation of compositions of deep fluids in geothermal activity of Pleistocene-Holocene volcanic fields of Lesser Caucasus

    Science.gov (United States)

    Meliksetian, Khachatur; Lavrushin, Vassily; Shahinyan, Hrach; Aidarkozhina, Altin; Navasardyan, Gevorg; Ermakov, Alexander; Zakaryan, Shushan; Prasolov, Edward; Manucharyan, Davit; Gyulnazaryan, Shushan; Grigoryan, Edmond

    2017-04-01

    It is widely accepted, that geothermal activity in the conductive heat flow processes, such as volcanism and hydrothermal activity, is manifestation of the thermal mass transfer process in the Earth's crust, where geothermal and geochemical processes are closely connected. Therefore, geochemistry and isotope compositions of thermal mineral waters within and on periphery of volcanic clusters may represent key indicators for better understanding of geothermal activity in geodynamically active zones. Geochemical features of heat and mass transport in hydrothermal systems related to active volcanic and fault systems in continental collision related orogenic elevated plateaus such as Anatolian-Armenian-Iranian highlands are still poorly understood. In this contribution we attempt to fill these gaps in our knowledge of relations of geochemical and geothermal processes in collision zones. We present new data on chemical compositions, trace element geochemistry of thermal waters of Lesser Caucasus, (Armenia) as well as isotope analysis of free gases such as {}3He/{}4He, {}40Ar/{}36Ar, δ{}13?(CO{}2), nitrogen δ{}15N(N{}2) and oxygen and hydrogen isotopes in water phases (δD, δ{}18O). To reveal some specific features of formation of fluid systems related to thermal activity in the areas of collision related active volcanism and active geodynamics a complex geochemical (SiO{}2, K-Na, Na-Li, Li-Mg) and isotope geothermometers (δ{}18O(CaCO{}3) - δ{}18O(H{}2O)) were applied. The distribution of δ{}13?(??{}2) values in free gases of mineral waters of Armenia demonstrates that gases related to Quaternary volcanic fields are characterized by relatively light δ{}13?(CO{}2) values close to mantle derived gases, while on periphery of volcanic systems relatively heavy values of δ{}13?(CO{}2) indicate strong influence of metamorphic and sedimentary derived carbon dioxide. Distribution of nitrogen isotopes δ{}15N(N{}2) demonstrate an inverse correlation with δ{}13?(CO{}2

  6. Radon surveys and monitoring at active volcanoes: an open window on deep hydrothermal systems and their dynamics

    Science.gov (United States)

    Cigolini, Corrado; Laiolo, Marco; Coppola, Diego

    2017-04-01

    The behavior of fluids in hydrothermal systems is critical in volcano monitoring and geothermal prospecting. Analyzing the time series of radon emissions on active volcanoes is strategic for detecting and interpreting precursory signals of changes in volcanic activity, eventually leading to eruptions. Radon is a radioactive gas generated from the decay of U bearing rocks, soils and magmas. Although radon has been regarded as a potential precursor of earthquakes, radon anomalies appear to be better suited to forecast volcanic eruptions since we know where paroxysms may occur and we can follow the evolution of volcanic activity. Radon mapping at active volcanoes is also a reliable tool to assess diffuse and concentrated degassing as well as efficiently detecting earthquake-volcano interactions. Systematic radon monitoring has been shown to be a key factor for evaluating the rise of volcanic and hydrothermal fluids. In fact, the decay properties of radon, the duration of radon anomalies together with sampling rates may be cross-checked with the chemistry of hydrothermal fluids (and their transport properties) to constrain fluids ascent rates and to infer the permeability and porosity of rocks in sectors surrounding the active conduits. We hereby further discuss the data of radon surveys and monitoring at Somma-Vesuvius, Stromboli and La Soufrière (Guadeloupe, Lesser Antilles). The integrated analysis of seismic and geochemical data, including radon emissions, may be successfully used in testing temperature distributions and variations of porosity and permeability in volcanic hydrothermal systems and can be used as a proxy to analyze geothermal reservoirs.

  7. Collateral variations between the concentrations of mercury and other water soluble ions in volcanic ash samples and volcanic activity during the 2014-2016 eruptive episodes at Aso volcano, Japan

    Science.gov (United States)

    Marumoto, Kohji; Sudo, Yasuaki; Nagamatsu, Yoshizumi

    2017-07-01

    During 2014-2016, the Aso volcano, located in the center of the Kyushu Islands, Japan, erupted and emitted large amounts of volcanic gases and ash. Two episodes of the eruption were observed; firstly Strombolian magmatic eruptive episodes from 25 November 2014 to the middle of May 2015, and secondly phreatomagmatic and phreatic eruptive episodes from September 2015 to February 2016. Bulk chemical analyses on total mercury (Hg) and major ions in water soluble fraction in volcanic ash fall samples were conducted. During the Strombolian magmatic eruptive episodes, total Hg concentrations averaged 1.69 ± 0.87 ng g- 1 (N = 33), with a range from 0.47 to 3.8 ng g- 1. In addition, the temporal variation of total Hg concentrations in volcanic ash varied with the amplitude change of seismic signals. In the Aso volcano, the volcanic tremors are always observed during eruptive stages and quiet interludes, and the amplitudes of tremors increase at eruptive stages. So, the temporal variation of total Hg concentrations could provide an indication of the level of volcanic activity. During the phreatomagmatic and phreatic eruptive episodes, on the other hand, total Hg concentrations in the volcanic ash fall samples averaged 220 ± 88 ng g- 1 (N = 5), corresponding to 100 times higher than those during the Strombolian eruptive episode. Therefore, it is possible that total Hg concentrations in volcanic ash samples are largely varied depending on the eruptive type. In addition, the ash fall amounts were also largely different among the two eruptive episodes. This can be also one of the factors controlling Hg concentrations in volcanic ash.

  8. Evidence for sub-lacustrine volcanic activity in Lake Bolsena (central Italy) revealed by high resolution seismic data sets

    Science.gov (United States)

    Lindhorst, Katja; Krastel, Sebastian; Wagner, Bernd; Schuerer, Anke

    2017-06-01

    The Bolsena caldera that formed between 0.6 and 0.2 Ma has a well preserved structural rim, which makes it an ideal site to study the tectonic and volcanic evolution of calderas. However, the main area is covered by a 150 m deep lake which makes it rather difficult to investigate the subsurface structure directly. To overcome this problem new high resolution hydro-acoustic surveys using a multichannel reflection seismic system and a sediment echo-sounder system were conducted in September 2012. As space was limited we used a rowing boat towed by a rubber boat to handle a 36 m long and 24 channel streamer to receive seismic reflections produced using a Mini GI-Gun (0.25 l). The subsurface structure of Lake Bolsena was imaged up to a sediment depth of 190 m, which is estimated to have filled over a period of 333 kyrs. However, massive pyroclastic flow deposits found in the deeper parts of the basin indicate an initial infill of volcanic deposits from two adjacent younger calderas, the Latera (W) and Montefiascone (SE) calderas. Our data suggest that the caldera has a long history of active volcanism, because the lacustrine sediments show post-sedimentary influences of geothermal fluids. We mapped several mound structures at various stratigraphic depths. Two volcanic structures outcrop at the modern lake surface implying recent activity. One of these structures is hardly covered by sediments and has a crater-like feature in its summit. The other structure shows a pockmark-like depression on top. Another observable feature is a partially sediment filled crater located in the western part of the lake which further implies the existence of a magma chamber located beneath the Bolsena caldera. Since the late Pleistocene and Holocene, the sedimentation was mainly hemipelagic evidenced by a sediment drape of up to 10 m thick sediment drape on the uppermost sediments. Beneath the drape we found evidence for a distal tephra layer likely related to an explosive eruption from

  9. Complex explosive volcanic activity on the Moon within Oppenheimer crater, Icarus

    Science.gov (United States)

    Bennett, Kristen A; Horgan, Briony H N; Gaddis, Lisa R.; Greenhagen, Benjamin T; Allen, Carlton C.; Hayne, Paul O; Bell, James F III; Paige, David A.

    2016-01-01

    Oppenheimer Crater is a floor-fractured crater located within the South Pole-Aitken basin on the Moon, and exhibits more than a dozen localized pyroclastic deposits associated with the fractures. Localized pyroclastic volcanism on the Moon is thought to form as a result of intermittently explosive Vulcanian eruptions under low effusion rates, in contrast to the higher-effusion rate, Hawaiian-style fire fountaining inferred to form larger regional deposits. We use Lunar Reconnaissance Orbiter Camera images and Diviner Radiometer mid-infrared data, Chandrayaan-1 orbiter Moon Mineralogy Mapper near-infrared spectra, and Clementine orbiter Ultraviolet/Visible camera images to test the hypothesis that the pyroclastic deposits in Oppenheimer crater were emplaced via Vulcanian activity by constraining their composition and mineralogy. Mineralogically, we find that the deposits are variable mixtures of orthopyroxene and minor clinopyroxene sourced from the crater floor, juvenile clinopyroxene, and juvenile iron-rich glass, and that the mineralogy of the pyroclastics varies both across the Oppenheimer deposits as a whole and within individual deposits. We observe similar variability in the inferred iron content of pyroclastic glasses, and note in particular that the northwest deposit, associated with Oppenheimer U crater, contains the most iron-rich volcanic glass thus far identified on the Moon, which could be a useful future resource. We propose that this variability in mineralogy indicates variability in eruption style, and that it cannot be explained by a simple Vulcanian eruption. A Vulcanian eruption should cause significant country rock to be incorporated into the pyroclastic deposit; however, large areas within many of the deposits exhibit spectra consistent with high abundances of juvenile phases and very little floor material. Thus, we propose that at least the most recent portion of these deposits must have erupted via a Strombolian or more continuous fire

  10. Late Quaternary incision and deposition in an active volcanic setting: The Volturno valley fill, southern Italy

    Science.gov (United States)

    Amorosi, Alessandro; Pacifico, Annamaria; Rossi, Veronica; Ruberti, Daniela

    2012-12-01

    Extensive illustration of depositional facies, ostracod and foraminiferal assemblages, and Late Quaternary stratigraphic architecture is offered for the first time from beneath the modern coastal plain of Volturno River, the longest river in southern Italy. Proximity to an active volcanic district, including quiescent Vesuvius Volcano, provides an easily identifiable stratigraphic marker (Campania Grey Tuff or CGT), up to 55 m thick, emplaced 39 ky cal BP by a large-volume explosive pyroclastic eruption. Identification of top CGT to a maximum depth of 30 m allows tracing out the shape of a 15-20 km wide Late Quaternary palaeovalley incised by Volturno River into the thick ignimbritic unit immediately after its deposition. A terraced palaeotopography of the valley flanks is reconstructed on the basis of core data. Above the basal fluvial deposits, the early Holocene transgressive facies consist of a suite of estuarine (freshwater to brackish) deposits. These are separated from overlying transgressive barrier sands by a distinctive wave ravinement surface. Upwards, a distinctive shallowing-upward succession of middle-late Holocene age is interpreted to reflect initiation and subsequent progradation of a wave-dominated delta system, with flanking strandplains, in response to reduced rate of sea-level rise. The turnaround from transgressive to highstand conditions is identified on the basis of subtle changes in the meiofauna. These enable tracking of the maximum flooding surface into its updip (lagoonal/estuarine) counterpart, thus highlighting the role of refined palaeontological criteria as a powerful tool for high-resolution sequence-stratigraphic studies.

  11. Intumescence and pore structure of alkali-activated volcanic glasses upon exposure to high temperatures

    Science.gov (United States)

    Erdogan, S. T.

    2015-12-01

    Structures formed with ground perlite, a natural volcanic glass, activated with NaOH solutions, are shown to possess the ability to expand up to ~225 % of their original volumes upon exposure to temperatures in the 200-600 °C range. Porous solid with 3-7 MPa compressive strength and ˜450 kg/m3 or higher density are obtained. The observed expansion is believed to occur due to a loss of silanol condensation water, as vapor and is accompanied by an up to ~20 % loss in mass. A drop in pH to near-neutral values supports this idea. The size and total amount of pores in the final solid are controlled by concentration of the NaOH solution and thermal processing conditions. The pores formed are observed to be ~1-10 μm to mm-sized. The ability of perlite-based solids to intumesce over specific temperature ranges could be beneficial in applications where absorption of thermal energy is necessary, such as passive fire protection.

  12. Volcanic Plume Measurements with UAV (Invited)

    Science.gov (United States)

    Shinohara, H.; Kaneko, T.; Ohminato, T.

    2013-12-01

    Volatiles in magmas are the driving force of volcanic eruptions and quantification of volcanic gas flux and composition is important for the volcano monitoring. Recently we developed a portable gas sensor system (Multi-GAS) to quantify the volcanic gas composition by measuring volcanic plumes and obtained volcanic gas compositions of actively degassing volcanoes. As the Multi-GAS measures variation of volcanic gas component concentrations in the pumped air (volcanic plume), we need to bring the apparatus into the volcanic plume. Commonly the observer brings the apparatus to the summit crater by himself but such measurements are not possible under conditions of high risk of volcanic eruption or difficulty to approach the summit due to topography etc. In order to overcome these difficulties, volcanic plume measurements were performed by using manned and unmanned aerial vehicles. The volcanic plume measurements by manned aerial vehicles, however, are also not possible under high risk of eruption. The strict regulation against the modification of the aircraft, such as installing sampling pipes, also causes difficulty due to the high cost. Application of the UAVs for the volcanic plume measurements has a big advantage to avoid these problems. The Multi-GAS consists of IR-CO2 and H2O gas analyzer, SO2-H2O chemical sensors and H2 semiconductor sensor and the total weight ranges 3-6 kg including batteries. The necessary conditions of the UAV for the volcanic plumes measurements with the Multi-GAS are the payloads larger than 3 kg, maximum altitude larger than the plume height and installation of the sampling pipe without contamination of the exhaust gases, as the exhaust gases contain high concentrations of H2, SO2 and CO2. Up to now, three different types of UAVs were applied for the measurements; Kite-plane (Sky Remote) at Miyakejima operated by JMA, Unmanned airplane (Air Photo Service) at Shinomoedake, Kirishima volcano, and Unmanned helicopter (Yamaha) at Sakurajima

  13. Embedded ARM System for Volcano Monitoring in Remote Areas: Application to the Active Volcano on Deception Island (Antarctica

    Directory of Open Access Journals (Sweden)

    Luis Miguel Peci

    2014-01-01

    Full Text Available This paper describes the development of a multi-parameter system for monitoring volcanic activity. The system permits the remote access and the connection of several modules in a network. An embedded ARMTM processor has been used, allowing a great flexibility in hardware configuration. The use of a complete Linux solution (DebianTM as Operating System permits a quick, easy application development to control sensors and communications. This provides all the capabilities required and great stability with relatively low energy consumption. The cost of the components and applications development is low since they are widely used in different fields. Sensors and commercial modules have been combined with other self-developed modules. The Modular Volcano Monitoring System (MVMS described has been deployed on the active Deception Island (Antarctica volcano, within the Spanish Antarctic Program, and has proved successful for monitoring the volcano, with proven reliability and efficient operation under extreme conditions. In another context, i.e., the recent volcanic activity on El Hierro Island (Canary Islands in 2011, this technology has been used for the seismic equipment and GPS systems deployed, thus showing its efficiency in the monitoring of a volcanic crisis.

  14. Embedded ARM system for volcano monitoring in remote areas: application to the active volcano on Deception Island (Antarctica).

    Science.gov (United States)

    Peci, Luis Miguel; Berrocoso, Manuel; Fernández-Ros, Alberto; García, Alicia; Marrero, José Manuel; Ortiz, Ramón

    2014-01-02

    This paper describes the development of a multi-parameter system for monitoring volcanic activity. The system permits the remote access and the connection of several modules in a network. An embedded ARM™ processor has been used, allowing a great flexibility in hardware configuration. The use of a complete Linux solution (Debian™) as Operating System permits a quick, easy application development to control sensors and communications. This provides all the capabilities required and great stability with relatively low energy consumption. The cost of the components and applications development is low since they are widely used in different fields. Sensors and commercial modules have been combined with other self-developed modules. The Modular Volcano Monitoring System (MVMS) described has been deployed on the active Deception Island (Antarctica) volcano, within the Spanish Antarctic Program, and has proved successful for monitoring the volcano, with proven reliability and efficient operation under extreme conditions. In another context, i.e., the recent volcanic activity on El Hierro Island (Canary Islands) in 2011, this technology has been used for the seismic equipment and GPS systems deployed, thus showing its efficiency in the monitoring of a volcanic crisis.

  15. Local influences of geothermal anomalies on permafrost distribution in an active volcanic island (Deception Island, Antarctica)

    Science.gov (United States)

    Goyanes, G.; Vieira, G.; Caselli, A.; Cardoso, M.; Marmy, A.; Santos, F.; Bernardo, I.; Hauck, C.

    2014-11-01

    This study aims at understanding the spatial distribution and characteristics of the frozen and unfrozen terrain in an alluvial fan on Deception Island, which is an active strato-volcano located in the Bransfield Strait (South Shetland Islands) with recent eruptions in 1967, 1969 and 1970. The alluvial fan is dominated by debris-flow, run-off and rock fall processes and permafrost occurs in several parts in the vicinity of anomalous geothermal heat flux. The aim is to assess the ways volcanic activity controls permafrost development and associated geomorphic dynamics using shallow subsurface, surface and air temperature measurements as well as thaw depth and electrical resistivity tomography (ERT) surveys. Results show a temperature increase with depth in the lower part of the fan reaching 13 °C at 0.80 m depth, without the presence of permafrost. The shallow borehole located at this site showed a stable thermal stratification all year-round, with only the upper 0.20 m reacting to meteorological forcing. In the upper part of the alluvial fan and debris cones, c. 100 m from the coast, frozen ground is present at c. 0.70 m depth. There, the shallow borehole shows a good coupling with air temperatures and the thermal regime favours the presence of permafrost. ERT shows the lowest resistivity values in the lower part of the alluvial fan and a highly resistivity zone in the upper sector of the fan and in the debris cones. These large variations in resistivity mark the presence of a saline water wedge from the sea into the fan, reaching frozen ground conditions about 100 m inland. It can be shown that the volcano-hydrothermal activity only inhibits frost development very locally, with frozen ground conditions occurring about 100 m away.

  16. Volcanic Catastrophes

    Science.gov (United States)

    Eichelberger, J. C.

    2003-12-01

    volcanism on humankind in the North Pacific, where Holocene time saw many caldera-forming eruptions in an area of comparatively intense human activity.

  17. Wireless system for seismic activity monitoring

    OpenAIRE

    Безвесільна, Олена Миколаївна; Козько, Констянтин Сергійович

    2014-01-01

    The article examines the concepts and principles of sensor networks operations, especially the one that is used to monitor seismic activity and potential natural disasters. It also describes the operating principle of the geographically distributed wireless system, represented by block diagrams of typical sensor nodes and base station, as well as constructive electrical circuit sensor node and the frequency generator radio transmissions the base station and sensor nodes, we formulate to calcu...

  18. Monitoring the Near-infrared Volcanic Flux from Io's Jupiter-facing Hemisphere from Fan Mountain Observatory

    Science.gov (United States)

    Skrutskie, Michael F.; Nelson, Matthew J.; Schmidt, Carl

    2016-10-01

    Fan Mountain Observatory, near Charlottesville, Virginia, is a dark-sky site that supports a number of telescopes including a 31-inch reflecting telescope equipped with a 1024x1024 HgCdTe 1-2.5 um (YJHK) imager. Reflected sunlight ordinarily overwhelms Io's comparatively weak K-band (2.0-2.4 um) volcanic emission in unresolved observations, however when Io is eclipsed in Jupiter's shadow even a small infrared-equipped telescope can detect Io's volcanic emission. The Fan Mountain Infrared Camera observed Io in eclipse at regular intervals, typically weekly, during the few months before and after Jupiter's March 2016 opposition. When in eclipse Io's Jupiter-facing hemisphere is oriented toward Earth with sub-Earth longitudes at the time of observation ranging from 345 - 360 degrees (pre-opposition) to 0 - 15 degrees (post-opposition). A K-band filter (2.04-2.42 um) provided a bulk measurement of Io's volcanic flux weighted largely toward the 2.4 um end of this filter given the typical 500K color temperature of the volcanic emission. Most epochs also included observation in a narrowband filter centered at 2.12 um that, when combined with the broadband "long" wavelength measurement, provided a proxy for color temperature. The K-band flux of Io varied by more than 2 magnitudes during the 7 month observation interval. The [2.12 um - K-band] color of the emission strongly correlated with the K-band flux in the expected sense that the color temperature of the emission increased when Io's broadband volcanic flux was the greatest. One epoch of TripleSpec near-IR Io eclipse spectroscopy (0.90 - 2.45 um; R~3000) from the Apache Point Observatory 3.5-meter telescope provided ground truth for transforming the filter photometry into quantitative temperatures.

  19. Developing International Guidelines on Volcanic Hazard Assessments for Nuclear Facilities

    Science.gov (United States)

    Connor, Charles

    2014-05-01

    Worldwide, tremendous progress has been made in recent decades in forecasting volcanic events, such as episodes of volcanic unrest, eruptions, and the potential impacts of eruptions. Generally these forecasts are divided into two categories. Short-term forecasts are prepared in response to unrest at volcanoes, rely on geophysical monitoring and related observations, and have the goal of forecasting events on timescales of hours to weeks to provide time for evacuation of people, shutdown of facilities, and implementation of related safety measures. Long-term forecasts are prepared to better understand the potential impacts of volcanism in the future and to plan for potential volcanic activity. Long-term forecasts are particularly useful to better understand and communicate the potential consequences of volcanic events for populated areas around volcanoes and for siting critical infrastructure, such as nuclear facilities. Recent work by an international team, through the auspices of the International Atomic Energy Agency, has focused on developing guidelines for long-term volcanic hazard assessments. These guidelines have now been implemented for hazard assessment for nuclear facilities in nations including Indonesia, the Philippines, Armenia, Chile, and the United States. One any time scale, all volcanic hazard assessments rely on a geologically reasonable conceptual model of volcanism. Such conceptual models are usually built upon years or decades of geological studies of specific volcanic systems, analogous systems, and development of a process-level understanding of volcanic activity. Conceptual models are used to bound potential rates of volcanic activity, potential magnitudes of eruptions, and to understand temporal and spatial trends in volcanic activity. It is these conceptual models that provide essential justification for assumptions made in statistical model development and the application of numerical models to generate quantitative forecasts. It is a

  20. Volcanic alert system (VAS) developed during the 2011-2014 El Hierro (Canary Islands) volcanic process

    Science.gov (United States)

    García, Alicia; Berrocoso, Manuel; Marrero, José M.; Fernández-Ros, Alberto; Prates, Gonçalo; De la Cruz-Reyna, Servando; Ortiz, Ramón

    2014-06-01

    The 2011 volcanic unrest at El Hierro Island illustrated the need for a Volcanic Alert System (VAS) specifically designed for the management of volcanic crises developing after long repose periods. The VAS comprises the monitoring network, the software tools for analysis of the monitoring parameters, the Volcanic Activity Level (VAL) management, and the assessment of hazard. The VAS presented here focuses on phenomena related to moderate eruptions, and on potentially destructive volcano-tectonic earthquakes and landslides. We introduce a set of new data analysis tools, aimed to detect data trend changes, as well as spurious signals related to instrumental failure. When data-trend changes and/or malfunctions are detected, a watchdog is triggered, issuing a watch-out warning (WOW) to the Monitoring Scientific Team (MST). The changes in data patterns are then translated by the MST into a VAL that is easy to use and understand by scientists, technicians, and decision-makers. Although the VAS was designed specifically for the unrest episodes at El Hierro, the methodologies may prove useful at other volcanic systems.

  1. New inferences from spectral seismic energy measurement of a link between regional seismicity and volcanic activity at Mt. Etna, Italy

    Science.gov (United States)

    Ortiz, R.; Falsaperla, S.; Marrero, J. M.; Messina, A.

    2009-04-01

    The existence of a relationship between regional seismicity and changes in volcanic activity has been the subject of several studies in the last years. Generally, activity in basaltic volcanoes such as Villarica (Chile) and Tungurahua (Ecuador) shows very little changes after the occurrence of regional earthquakes. In a few cases volcanic activity has changed before the occurrence of regional earthquakes, such as observed at Teide, Tenerife, in 2004 and 2005 (Tárraga et al., 2006). In this paper we explore the possible link between regional seismicity and changes in volcanic activity at Mt. Etna in 2006 and 2007. On 24 November, 2006 at 4:37:40 GMT an earthquake of magnitude 4.7 stroke the eastern coast of Sicily. The epicenter was localized 50 km SE of the south coast of the island, and at about 160 km from the summit craters of Mt. Etna. The SSEM (Spectral Seismic Energy Measurement) of the seismic signal at stations at 1 km and 6 km from the craters highlights that four hours before this earthquake the energy associated with volcanic tremor increased, reached a maximum, and finally became steady when the earthquake occurred. Conversely, neither before nor after the earthquake, the SSEM of stations located between 80 km and 120 km from the epicentre and outside the volcano edifice showed changes. On 5 September, 2007 at 21:24:13 GMT an earthquake of magnitude 3.2 and 7.9 km depth stroke the Lipari Island, at the north of Sicily. About 38 hours before the earthquake occurrence, there was an episode of lava fountain lasting 20 hours at Etna volcano. The SSEM of the seismic signal recorded during the lava fountain at a station located at 6 km from the craters highlights changes heralding this earthquake ten hours before its occurrence using the FFM method (e.g., Voight, 1988; Ortiz et al., 2003). A change in volcanic activity - with the onset of ash emission and Strombolian explosions - was observed a couple of hours before the occurrence of the regional

  2. Multistation alarm system for eruptive activity based on the automatic classification of volcanic tremor: specifications and performance

    Science.gov (United States)

    Langer, Horst; Falsaperla, Susanna; Messina, Alfio; Spampinato, Salvatore

    2015-04-01

    With over fifty eruptive episodes (Strombolian activity, lava fountains, and lava flows) between 2006 and 2013, Mt Etna, Italy, underscored its role as the most active volcano in Europe. Seven paroxysmal lava fountains at the South East Crater occurred in 2007-2008 and 46 at the New South East Crater between 2011 and 2013. Month-lasting lava emissions affected the upper eastern flank of the volcano in 2006 and 2008-2009. On this background, effective monitoring and forecast of volcanic phenomena are a first order issue for their potential socio-economic impact in a densely populated region like the town of Catania and its surroundings. For example, explosive activity has often formed thick ash clouds with widespread tephra fall able to disrupt the air traffic, as well as to cause severe problems at infrastructures, such as highways and roads. For timely information on changes in the state of the volcano and possible onset of dangerous eruptive phenomena, the analysis of the continuous background seismic signal, the so-called volcanic tremor, turned out of paramount importance. Changes in the state of the volcano as well as in its eruptive style are usually concurrent with variations of the spectral characteristics (amplitude and frequency content) of tremor. The huge amount of digital data continuously acquired by INGV's broadband seismic stations every day makes a manual analysis difficult, and techniques of automatic classification of the tremor signal are therefore applied. The application of unsupervised classification techniques to the tremor data revealed significant changes well before the onset of the eruptive episodes. This evidence led to the development of specific software packages related to real-time processing of the tremor data. The operational characteristics of these tools - fail-safe, robustness with respect to noise and data outages, as well as computational efficiency - allowed the identification of criteria for automatic alarm flagging. The

  3. Time variability of Io's volcanic activity from near-IR adaptive optics observations on 100 nights in 2013-2015

    Science.gov (United States)

    de Kleer, Katherine; de Pater, Imke

    2016-12-01

    Jupiter's moon Io is a dynamic target, exhibiting extreme and time-variable volcanic activity powered by tidal forcing from Jupiter. We have conducted a campaign of high-cadence observations of Io with the goal of characterizing its volcanic activity. Between Aug 2013 and the end of 2015, we imaged Io on 100 nights in the near-infrared with adaptive optics on the Keck and Gemini N telescopes, which resolve emission from individual volcanic hot spots. During our program, we made over 400 detections of 48 distinct hot spots, some of which were detected 30+ times. We use these observations to derive a timeline of global volcanic activity on Io, which exhibits wide variability from month to month. The timelines of thermal activity at individual volcanic centers have geophysical implications, and will permit future characterization by others. We evaluate hot spot detection limits and give a simple parameterization of the minimum detectable intensity as a function of emission angle, which can be applied to other analyses. We detected three outburst eruptions in August 2013, but no other outburst-scale events were observed in the subsequent ∼90 observations. Either the cluster of events in August 2013 was a rare occurrence, or there is a mechanism causing large events to occur closely-spaced in time. We also detected large eruptions (though not of outburst scale) within days of one another at Kurdalagon Patera and Sethlaus/Gabija Paterae in 2015. As was also seen in the Galileo dataset, the hot spots we detected can be separated into two categories based on their thermal emission: those that are persistently active for 1 year or more at moderate intensity, and those that are only briefly active, are time-variable, and often reach large intensities. A small number of hot spots in the latter category appear and subside in a matter of days, reaching particularly high intensities; although these are not bright enough to qualify as outbursts, their thermal signatures follow

  4. Sentinel-1 automatic processing chain for volcanic and seismic areas monitoring within the Geohazards Exploitation Platform (GEP)

    Science.gov (United States)

    De Luca, Claudio; Zinno, Ivana; Manunta, Michele; Lanari, Riccardo; Casu, Francesco

    2016-04-01

    The microwave remote sensing scenario is rapidly evolving through development of new sensor technology for Earth Observation (EO). In particular, Sentinel-1A (S1A) is the first of a sensors' constellation designed to provide a satellite data stream for the Copernicus European program. Sentinel-1A has been specifically designed to provide, over land, Differential Interferometric Synthetic Aperture Radar (DInSAR) products to analyze and investigate Earth's surface displacements. S1A peculiarities include wide ground coverage (250 km of swath), C-band operational frequency and short revisit time (that will reduce from 12 to 6 days when the twin system Sentinel-1B will be placed in orbit during 2016). Such characteristics, together with the global coverage acquisition policy, make the Sentinel-1 constellation to be extremely suitable for volcanic and seismic areas studying and monitoring worldwide, thus allowing the generation of both ground displacement information with increasing rapidity and new geological understanding. The main acquisition mode over land is the so called Interferometric Wide Swath (IWS) that is based on the Terrain Observation by Progressive Scans (TOPS) technique and that guarantees the mentioned S1A large coverage characteristics at expense of a not trivial interferometric processing. Moreover, the satellite spatial coverage and the reduced revisit time will lead to an exponential increase of the data archives that, after the launch of Sentine-1B, will reach about 3TB per day. Therefore, the EO scientific community needs from the one hand automated and effective DInSAR tools able to address the S1A processing complexity, and from the other hand the computing and storage capacities to face out the expected large amount of data. Then, it is becoming more crucial to move processors and tools close to the satellite archives, being not efficient anymore the approach of downloading and processing data with in-house computing facilities. To address

  5. Mesozooplankton distribution near an active volcanic island in the Andaman Sea (Barren Island).

    Science.gov (United States)

    Pillai, Honey U K; Jayaraj, K A; Rafeeq, M; Jayalakshmi, K J; Revichandran, C

    2011-05-01

    The study addresses the distribution and diversity of mesozooplankton near the active volcano-Barren Island (Andaman Sea) in the context of persistent volcanic signature and warm air pool existing for the last few months. Sampling was done from the stations along the west and east side of the volcano up to a depth of 1,000 m during the inter monsoon (April) of 2006. Existence of feeble warm air pool was noticed around the Island (Atm. Temp. 29°C). Sea surface temperature recorded as 29.9°C on the west and 29.6°C on the east side stations. High mesozooplankton biomass was observed in the study area than the earlier reports. High density and biomass observed in the surface layer decreased significantly to the deeper depths. Lack of correlation was observed between mesozooplankton biomass and density with chl. a. Twenty-three mesozooplankton taxa were observed with copepoda as the dominant taxa followed by chaetognatha. The relative abundance of chaetognatha considerably affected the copepod population density in the surface layer. A noticeable feature was the presence of cumaceans, a hyperbenthic fauna in the surface, mixed layer and thermocline layer on the western side station where the volcano discharges in to the sea. The dominant order of copepoda, the calanoida was represented by 52 species belonging to 17 families. The order poecilostomatoida also had a significant contribution. Copepods exhibited a clear difference in their distribution pattern in different depth layers. The families Calanidae and Pontellidae showed a clear dominance in the surface whereas small-sized copepods belonging to the families Clausocalanidae and Paracalanidae were observed as the predominant community in the mixed layer and thermocline layer depth. Families Metridinidae, Augaptilidae and Aetideidae were observed as dominant in deeper layers.

  6. Groundwater flow processes and mixing in active volcanic systems: the case of Guadalajara (Mexico)

    Science.gov (United States)

    Hernández-Antonio, A.; Mahlknecht, J.; Tamez-Meléndez, C.; Ramos-Leal, J.; Ramírez-Orozco, A.; Parra, R.; Ornelas-Soto, N.; Eastoe, C. J.

    2015-09-01

    other active volcanic systems on Earth.

  7. Learning to recognize volcanic non-eruptions

    Science.gov (United States)

    Poland, Michael P.

    2010-01-01

    An important goal of volcanology is to answer the questions of when, where, and how a volcano will erupt—in other words, eruption prediction. Generally, eruption predictions are based on insights from monitoring data combined with the history of the volcano. An outstanding example is the A.D. 1980–1986 lava dome growth at Mount St. Helens, Washington (United States). Recognition of a consistent pattern of precursors revealed by geophysical, geological, and geochemical monitoring enabled successful predictions of more than 12 dome-building episodes (Swanson et al., 1983). At volcanic systems that are more complex or poorly understood, probabilistic forecasts can be useful (e.g., Newhall and Hoblitt, 2002; Marzocchi and Woo, 2009). In such cases, the probabilities of different types of volcanic events are quantified, using historical accounts and geological studies of a volcano's past activity, supplemented by information from similar volcanoes elsewhere, combined with contemporary monitoring information.

  8. Volcanic-ash hazard to aviation during the 2003-2004 eruptive activity of Anatahan volcano, Commonwealth of the Northern Mariana Islands

    Science.gov (United States)

    Guffanti, M.; Ewert, J.W.; Gallina, G.M.; Bluth, G.J.S.; Swanson, G.L.

    2005-01-01

    Within the Commonwealth of the Northern Mariana Islands (CNMI), Anatahan is one of nine active subaerial volcanoes that pose hazards to major air-traffic routes from airborne volcanic ash. The 2003-2004 eruptive activity of Anatahan volcano affected the region's aviation operations for 3 days in May 2003. On the first day of the eruption (10 May 2003), two international flights from Saipan to Japan were cancelled, and several flights implemented ash-avoidance procedures. On 13 May 2003, a high-altitude flight through volcanic gas was reported, with no perceptible damage to the aircraft. TOMS and MODIS analysis of satellite data strongly suggests that no significant ash and only minor amounts of SO2 were involved in the incident, consistent with crew observations. On 23 May 2003, airport operations were disrupted when tropical-cyclone winds dispersed ash to the south, dusting Saipan with light ashfall and causing flight cancellations there and at Guam 320 km south of the volcano. Operational (near-real-time) monitoring of ash clouds produced by Anatahan has been conducted since the first day of the eruption on 10 May 2003 by the Washington Volcanic Ash Advisory Center (VAAC). The VAAC was among the first groups outside of the immediate area of the volcano to detect and report on the unexpected eruption of Anatahan. After being contacted about an unusual cloud by National Weather Service forecasters in Guam at 1235 UTC on 10 May 2003, the VAAC analyzed GOES 9 images, confirming Anatahan as the likely source of an ash cloud and estimating that the eruption began at about 0730 UTC. The VAAC issued its first Volcanic Ash Advisory for Anatahan at 1300 UTC on 10 May 2003 more than 5 h after the start of the eruption, the delay reflecting the difficulty of detecting and confirming a surprise eruption at a remote volcano with no in situ real-time geophysical monitoring. The initial eruption plume reached 10.7-13.4 km (35,000-44,000 ft), well into jet cruise altitudes

  9. Evidences of active and ancient Volcanism on Mars. A review. Second Part

    Directory of Open Access Journals (Sweden)

    P. HÉDERVÀRI

    1974-06-01

    Full Text Available The results of recent research have brought some further evidence of volcanism on the planet Mars. At the same time certain erroneous descriptions and conclusions, which are to be found in the first paper (3, are here corrected.

  10. Mercury as a proxy for volcanic activity during extreme environmental turnover

    DEFF Research Database (Denmark)

    Sial, A.N.; Lacerda, L.D.; Ferreira, V.P.

    2013-01-01

    The usually low geological background concentrations of Hg makes this trace element suitable for identifying accumulation pulses in sediments that can be tentatively related to weathering processes and thus to climatic changes. Intense volcanism has witnessed the Cretaceous–Paleogene transition (...

  11. Short-term volcanic hazard assessment through Bayesian inference: retrospective application to the Pinatubo 1991 volcanic crisis

    Science.gov (United States)

    Sobradelo, Rosa; Martí, Joan

    2015-01-01

    One of the most challenging aspects of managing a volcanic crisis is the interpretation of the monitoring data, so as to anticipate to the evolution of the unrest and implement timely mitigation actions. An unrest episode may include different stages or time intervals of increasing activity that may or may not precede a volcanic eruption, depending on the causes of the unrest (magmatic, geothermal or tectonic). Therefore, one of the main goals in monitoring volcanic unrest is to forecast whether or not such increase of activity will end up with an eruption, and if this is the case, how, when, and where this eruption will take place. As an alternative method to expert elicitation for assessing and merging monitoring data and relevant past information, we present a probabilistic method to transform precursory activity into the probability of experiencing a significant variation by the next time interval (i.e. the next step in the unrest), given its preceding evolution, and by further estimating the probability of the occurrence of a particular eruptive scenario combining monitoring and past data. With the 1991 Pinatubo volcanic crisis as a reference, we have developed such a method to assess short-term volcanic hazard using Bayesian inference.

  12. Active Volcano Monitoring using a Space-based Hyperspectral Imager

    Science.gov (United States)

    Cipar, J. J.; Dunn, R.; Cooley, T.

    2010-12-01

    Active volcanoes occur on every continent, often in close proximity to heavily populated areas. While ground-based studies are essential for scientific research and disaster mitigation, remote sensing from space can provide rapid and continuous monitoring of active and potentially active volcanoes [Ramsey and Flynn, 2004]. In this paper, we report on hyperspectral measurements of Kilauea volcano, Hawaii. Hyperspectral images obtained by the US Air Force TacSat-3/ARTEMIS sensor [Lockwood et al, 2006] are used to obtain estimates of the surface temperatures for the volcano. ARTEMIS measures surface-reflected light in the visible, near-infrared, and short-wave infrared bands (VNIR-SWIR). The SWIR bands are known to be sensitive to thermal radiation [Green, 1996]. For example, images from the NASA Hyperion hyperspectral sensor have shown the extent of wildfires and active volcanoes [Young, 2009]. We employ the methodology described by Dennison et al, (2006) to obtain an estimate of the temperature of the active region of Kilauea. Both day and night-time images were used in the analysis. To improve the estimate, we aggregated neighboring pixels. The active rim of the lava lake is clearly discernable in the temperature image, with a measured temperature exceeding 1100o C. The temperature decreases markedly on the exterior of the summit crater. While a long-wave infrared (LWIR) sensor would be ideal for volcano monitoring, we have shown that the thermal state of an active volcano can be monitored using the SWIR channels of a reflective hyperspectral imager. References: Dennison, Philip E., Kraivut Charoensiri, Dar A. Roberts, Seth H. Peterson, and Robert O. Green (2006). Wildfire temperature and land cover modeling using hyperspectral data, Remote Sens. Environ., vol. 100, pp. 212-222. Green, R. O. (1996). Estimation of biomass fire temperature and areal extent from calibrated AVIRIS spectra, in Summaries of the 6th Annual JPL Airborne Earth Science Workshop, Pasadena, CA

  13. Anatahan, Northern Mariana Islands: Reconnaissance geological observations during and after the volcanic crisis of spring 1990, and monitoring prior to the May 2003 eruption

    Science.gov (United States)

    Rowland, S.K.; Lockwood, J.P.; Trusdell, F.A.; Moore, R.B.; Sako, M.K.; Koyanagi, R.Y.; Kojima, G.

    2005-01-01

    Anatahan island is 9.5 km east-west by 3.5 km north-south and truncated by an elongate caldera 5 km east-west by 2.5 km north-south. A steep-walled pit crater ???1 km across and ???200 m deep occupies the eastern part of the caldera. The island is the summit region of a mostly submarine stratovolcano. The oldest subaerial rocks (stage 1) are exposed low on the outer flanks and in the caldera walls. These include thick (???10 m) and thin (2-3 m) lava flows, well-indurated tuffs, and scoria units that make up the bulk of the island. Rock compositions range from basaltic andesite to dacite, and most are plagioclase-phyric. On the steep north and south flanks of the volcano, these rocks are cut by numerous east-west-oriented, few-hundred-m-long lineaments of undetermined origin. Indurated breccias unconformably overlie scarps cut into stage 1 units low on the south flank. Intermediate-age eruptive units (stage 2) include caldera-filling lava flows and pyroclastic deposits and, on the outer flanks, vents and valley-filling lava flows. The youngest pre-2003 volcanic unit on Anatahan (stage 3) is a hydromagmatic surge and fall deposit rich in accretionary lapilli. Prior to 2003, this unit was found over almost the entire island, and in many places original depositional surfaces and outcrops could be found in high-energy environments along the coast, indicating a young (but undetermined) age. During reconnaissance visits in 1990, 1992, 1994, and 2001, geothermal activity (fumaroles as well as pits with boiling, sediment-laden pools) was observed in the southern part of the pit crater. In March and April 1990, increased local seismicity, a large regional earthquake, and reported increased fumarolic activity in the pit crater prompted evacuation of Anatahan village, at the west end of the island. Our first field investigation took place in late April 1990 to assess the level of volcanic unrest, conduct reconnaissance geological observations, collect rock and geothermal water

  14. Inversion of SAR data in active volcanic areas by optimization techniques

    Directory of Open Access Journals (Sweden)

    G. Nunnari

    2005-01-01

    Full Text Available The inversion problem concerns the identification of parameters of a volcanic source causing observable changes in ground deformation data recorded in volcanic areas. In particular, this paper deals with the inversion of ground deformation measured by using SAR (Synthetic Aperture Radar interferometry and an inversion approach formulated in terms of an optimization problem is proposed. Based on this inversion scheme, it is shown that the problem of inverting ground deformation data in terms of a single source, of Mogi or Okada type, is numerically well conditioned. In the paper, two case studies of inverting actual SAR data recorded on Mt. Etna during eruptions occurring in 1998 and 2001 are investigated, showing the suitability of the proposed technique.

  15. Relationship between earthquake and volcanic eruption inferred from historical records

    Institute of Scientific and Technical Information of China (English)

    陈洪洲; 高峰; 吴雪娟; 孟宪森

    2004-01-01

    A large number of seismic records are discovered for the first time in the historical materials about Wudalianchi volcanic group eruption in 1720~1721, which provides us with abundant volcanic earthquake information. Based on the written records, the relationship between earthquake and volcanic eruption is discussed in the paper. Furthermore it is pointed that earthquake swarm is an important indication of volcanic eruption. Therefore, monitoring volcanic earthquakes is of great significance for forecasting volcanic eruption.

  16. Chlorine isotope and Cl-Br fractionation in fluids of Poás volcano (Costa Rica): Insight into an active volcanic-hydrothermal system

    Science.gov (United States)

    Rodríguez, Alejandro; Eggenkamp, H. G. M.; Martínez-Cruz, María; van Bergen, Manfred J.

    2016-10-01

    concluded that combined monitoring of δ37Cl and Br/Cl in Laguna Caliente and adjacent fumaroles provides valuable information on activity in the subsurface hydrothermal system with significant relevance for volcanic surveillance of Poás.

  17. Quality Assurance Project Plan for Facility Effluent Monitoring Plan activities

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, T.P.

    1994-10-20

    This Quality Assurance Project Plan addresses the quality assurance requirements for the activities associated with the Facility Effluent Monitoring Plans, which are part of the overall Hanford Site Environmental Protection Plan. This plan specifically applies to the sampling and analysis activities and continuous monitoring performed for all Facility Effluent Monitoring Plan activities conducted by Westinghouse Hanford Company. It is generic in approach and will be implemented in conjunction with the specific requirements of the individual Facility Effluent Monitoring Plans.

  18. Short-lived tectonic switch mechanism for long-term pulses of volcanic activity after mega-thrust earthquakes

    Directory of Open Access Journals (Sweden)

    M. Lupi

    2013-06-01

    Full Text Available Eruptive rates in volcanic arcs increase significantly after mega-thrust earthquakes in subduction zones. Over short to intermediate time periods the link between mega-thrust earthquakes and arc response can be attributed to dynamic triggering processes or static stress changes, but a fundamental mechanism that controls long-term pulses of volcanic activity after mega-thrust earthquakes has not been proposed yet. Using geomechanical, geological, and geophysical arguments, we propose that increased eruption rates over longer timescales are due to the relaxation of the compressional regime that accompanies mega-thrust subduction zone earthquakes. More specifically, the reduction of the horizontal stress σh promotes the occurrence of short-lived strike-slip kinematics rather than reverse faulting in the volcanic arc. The relaxation of the pre-earthquake compressional regime facilitates magma mobilization by providing a short-circuit pathway to shallow depths by significantly increasing the hydraulic properties of the system. The timescale for the onset of strike-slip faulting depends on the degree of shear stress accumulated in the arc during inter-seismic periods, which in turn is connected to the degree of strain-partitioning at convergent margins. We performed Coulomb stress transfer analysis to determine the order of magnitude of the stress perturbations in present-day volcanic arcs in response to five actual mega-thrust earthquakes; the 2005 M8.6, 2007 M8.5, and 2007 M7.9 Sumatra earthquakes; the 2010 M8.8 Maule, Chile earthquake; and the 2011 M9.0 Tohoku, Japan earthquake. We find that all, but one, the shallow earthquakes that occurred in the arcs of Sumatra, Chile and Japan show a marked lateral component. Our hypothesis suggests that the long-term response of volcanic arcs to subduction zone mega-thrust earthquakes will be manifested as predominantly strike-slip seismic events, and that these future earthquakes will be followed closely by

  19. A new neutron monitor with silver activation

    CERN Document Server

    Luszik-Bhadra, M; Hohmann, E

    2010-01-01

    A moderator-type neutron monitor has been developed, which registers delayed beta rays from neutron-induced silver activation and which is able to measure dose equivalent in pulsed fields with peak dose rates of several thousand Sv h(-1). The monitor uses four silicon diodes in the centre of a polyethylene moderator, 30 cm in diameter. Two of the diodes are covered by natural silver foils and two of them by tin foils. The latter are used to subtract photon-induced pulses. For registering signals, a pulse height threshold is set at 662 key, which minimizes the effect of Cs-137 and lower energy radiation and - in addition - enhances the detection of beta rays from the shorter half-life silver isotope Ag-110 (25 s) as compared to the longer half-life isotope Ag-108 (144 s). The results of measurements in neutron and photon calibration fields, of MCNPX neutron response calculations and of first measurements in a high-intensity pulsed field at the PSI accelerator are shown. (c) 2010 Elsevier Ltd. All rights reserv...

  20. Assessing physical activity using wearable monitors: measures of physical activity

    National Research Council Canada - National Science Library

    Butte, Nancy F; Ekelund, Ulf; Westerterp, Klaas R

    2012-01-01

    .... Six main categories of wearable monitors are currently available to investigators: pedometers, load transducers/foot-contact monitors, accelerometers, HR monitors, combined accelerometer and HR monitors, and multiple sensor systems...

  1. Influence of seismic processes and volcanic activity on the formation of disastrous floods

    Science.gov (United States)

    Trifonov, Dmitriy

    2014-05-01

    models of hydraulic systems, but ultimately due to difference of pressures in their respective segments and areas of the transport network. At the exit of the groundwater on the surface such change in pressure is connected both with the state of the actual water flow in underground cavities, or violations of the structure (topology) of 3D-network. As one of the major and sudden reasons of change of pressure in the underground system can serve seismic processes, including volcanic eruptions (as magmatic and ash). During these processes enormous underground space can be freed from the dense rock. This leads to rapid changes in pressure and that, in principle, a new topology of 3D network and water flows in it. It is important that such dynamic processes occur over huge distances in underground basins of thousands of kilometers [3], of course, with a certain time delay. In the result of the analysis of large-scale flooding in Russia in 2001-2002, as well as the catastrophic floods in Western Europe, in the Amur region of Russia and in the state of Colorado USA in 2013, a correlation between seismic and volcanic activities and floods, expressed by specific numerical correlation coefficients, has been revealed. For example, knowing the date, location and magnitude of an earthquake, we can identify potentially dangerous territories in the aspect of the probability of occurrence of floods, because the stresses in the crust, spreading from the hypocenter of earthquakes, and their subsequent relaxation are one of the most important factors of floods. Mechanisms of distribution of these stresses are well-studied today [2] unlike their influence on the groundwater. The defined boundaries of potentially dangerous sites are broad enough; with regard to the direction of distribution of stress, it is about the sectors in 40 degrees (from the line of the movement of the crustal plate) in the direction from the boundaries of lithospheric plates. Distribution of this impact occurs, as a

  2. Seismicity and volcanic activity in Japan based on crustal thermal activity. 1; Chikaku no netsukatsudo ni motozuku Nippon no jishin kazan katsudo. 1

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, M. [Tokai Univ., Tokyo (Japan). School of Marine Science and Technology

    1996-05-01

    This paper describes the following matters about correlation between seismic and volcanic activities and thermal energy. Investigations on the status of seismic and volcanic activities in the Japanese archipelago during about 400 years in the past reveals the following matters: noticing earthquakes with magnitudes of upper M6 to about M7, flows of energy going outward from deep crust of the earth repeat ups and downs, whereas several prominent rising periods having certain time widths can be seen; volcanic activities are included in the rising period at the same rank as seismic activities; with regard to years 1900 and on, the similar fact can be seen if the Japanese archipelago is divided into a north portion, a south portion, and an extremely south portion southern than the Hiuga area; and the present time is going toward a period of rise in energy flows. In other words, it is thought that the crust and the uppermost portion of the mantle form one body like an organic body, making an action like a geyser releasing the energy outward. 3 refs., 2 figs., 1 tab.

  3. Stability Evaluation of Volcanic Slope Subjected to Rainfall and Freeze-Thaw Action Based on Field Monitoring

    Directory of Open Access Journals (Sweden)

    Shima Kawamura

    2011-01-01

    Full Text Available Rainfall-induced failures of natural and artificial slopes such as cut slopes, which are subjected to freezing and thawing, have been frequently reported in Hokkaido, Japan. In particular, many failures occur intensively from spring to summer seasons. Despite numerous field studies, explanation of their mechanical behavior based on in situ data has not yet been completely achieved due to the difficulty in grasping failure conditions. This study aims at clarifying the aspects of in-situ volcanic slopes subjected to rainfall and freeze-thaw action. The changes in soil moisture, pore pressure, deformations, and temperatures in the slope were investigated using soil moisture meters, tensiometers, thermocouple sensors, clinometers, settlement gauges, an anemovane, a snow gauge, and a rainfall gauge. The data generated from these measures indicated deformation in the slope examined mainly proceeded during the drainage process according to changes in soil moisture. Based on this data, a prediction method for failures is discussed in detail.

  4. Mesozooplankton distribution near an active volcanic island in the Andaman Sea (Barren Island)

    Digital Repository Service at National Institute of Oceanography (India)

    Pillai, H.U.K.; Jayaraj, K.A.; Rafeeq, M.; Jayalakshmi, K.J.; Revichandran, C.

    predation might happened in the surface. Copepods are important food items for chaetognaths (Liang and Vega-Pérez 1995), and they play an extremely important role in energy transfer to higher trophic levels (Terazaki 1998; Fulmer and Bollens 2005). It has... volcanic signature observed around Barren Island, Andaman Sea, India. Marine Geophysical Researches. doi:10.1007/ s11001–006–9008-z. Liang, T. H., & Vega-Pérez, L. A. (1995). Studies on chaetognaths off Ubatuba region, Brazil. II. Feeding habits...

  5. A Broadly-Based Training Program in Volcano Hazards Monitoring at the Center for the Study of Active Volcanoes

    Science.gov (United States)

    Thomas, D. M.; Bevens, D.

    2015-12-01

    The Center for the Study of Active Volcanoes, in cooperation with the USGS Volcano Hazards Program at HVO and CVO, offers a broadly based volcano hazards training program targeted toward scientists and technicians from developing nations. The program has been offered for 25 years and provides a hands-on introduction to a broad suite of volcano monitoring techniques, rather than detailed training with just one. The course content has evolved over the life of the program as the needs of the trainees have changed: initially emphasizing very basic monitoring techniques (e.g. precise leveling, interpretation of seismic drum records, etc.) but, as the level of sophistication of the trainees has increased, training in more advanced technologies has been added. Currently, topics of primary emphasis have included volcano seismology and seismic networks; acquisition and modeling of geodetic data; methods of analysis and monitoring of gas geochemistry; interpretation of volcanic deposits and landforms; training in LAHARZ, GIS mapping of lahar risks; and response to and management of volcanic crises. The course also provides training on public outreach, based on CSAV's Hawaii-specific hazards outreach programs, and volcano preparedness and interactions with the media during volcanic crises. It is an intensive eight week course with instruction and field activities underway 6 days per week; it is now offered in two locations, Hawaii Island, for six weeks, and the Cascades volcanoes of the Pacific Northwest, for two weeks, to enable trainees to experience field conditions in both basaltic and continental volcanic environments. The survival of the program for more than two decades demonstrates that a need for such training exists and there has been interaction and contribution to the program by the research community, however broader engagement with the latter continues to present challenges. Some of the reasons for this will be discussed.

  6. Geosphere-biosphere interactions in bio-activity volcanic lakes: evidences from Hule and Rìo Cuarto (Costa Rica).

    Science.gov (United States)

    Cabassi, Jacopo; Tassi, Franco; Mapelli, Francesca; Borin, Sara; Calabrese, Sergio; Rouwet, Dmitri; Chiodini, Giovanni; Marasco, Ramona; Chouaia, Bessem; Avino, Rosario; Vaselli, Orlando; Pecoraino, Giovannella; Capecchiacci, Francesco; Bicocchi, Gabriele; Caliro, Stefano; Ramirez, Carlos; Mora-Amador, Raul

    2014-01-01

    Hule and Río Cuarto are maar lakes located 11 and 18 km N of Poás volcano along a 27 km long fracture zone, in the Central Volcanic Range of Costa Rica. Both lakes are characterized by a stable thermic and chemical stratification and recently they were affected by fish killing events likely related to the uprising of deep anoxic waters to the surface caused by rollover phenomena. The vertical profiles of temperature, pH, redox potential, chemical and isotopic compositions of water and dissolved gases, as well as prokaryotic diversity estimated by DNA fingerprinting and massive 16S rRNA pyrosequencing along the water column of the two lakes, have highlighted that different bio-geochemical processes occur in these meromictic lakes. Although the two lakes host different bacterial and archaeal phylogenetic groups, water and gas chemistry in both lakes is controlled by the same prokaryotic functions, especially regarding the CO2-CH4 cycle. Addition of hydrothermal CO2 through the bottom of the lakes plays a fundamental priming role in developing a stable water stratification and fuelling anoxic bacterial and archaeal populations. Methanogens and methane oxidizers as well as autotrophic and heterotrophic aerobic bacteria responsible of organic carbon recycling resulted to be stratified with depth and strictly related to the chemical-physical conditions and availability of free oxygen, affecting both the CO2 and CH4 chemical concentrations and their isotopic compositions along the water column. Hule and Río Cuarto lakes were demonstrated to contain a CO2 (CH4, N2)-rich gas reservoir mainly controlled by the interactions occurring between geosphere and biosphere. Thus, we introduced the term of bio-activity volcanic lakes to distinguish these lakes, which have analogues worldwide (e.g. Kivu: D.R.C.-Rwanda; Albano, Monticchio and Averno: Italy; Pavin: France) from volcanic lakes only characterized by geogenic CO2 reservoir such as Nyos and Monoun (Cameroon).

  7. Geosphere-Biosphere Interactions in Bio-Activity Volcanic Lakes: Evidences from Hule and Rìo Cuarto (Costa Rica)

    Science.gov (United States)

    Cabassi, Jacopo; Tassi, Franco; Mapelli, Francesca; Borin, Sara; Calabrese, Sergio; Rouwet, Dmitri; Chiodini, Giovanni; Marasco, Ramona; Chouaia, Bessem; Avino, Rosario; Vaselli, Orlando; Pecoraino, Giovannella; Capecchiacci, Francesco; Bicocchi, Gabriele; Caliro, Stefano; Ramirez, Carlos; Mora-Amador, Raul

    2014-01-01

    Hule and Río Cuarto are maar lakes located 11 and 18 km N of Poás volcano along a 27 km long fracture zone, in the Central Volcanic Range of Costa Rica. Both lakes are characterized by a stable thermic and chemical stratification and recently they were affected by fish killing events likely related to the uprising of deep anoxic waters to the surface caused by rollover phenomena. The vertical profiles of temperature, pH, redox potential, chemical and isotopic compositions of water and dissolved gases, as well as prokaryotic diversity estimated by DNA fingerprinting and massive 16S rRNA pyrosequencing along the water column of the two lakes, have highlighted that different bio-geochemical processes occur in these meromictic lakes. Although the two lakes host different bacterial and archaeal phylogenetic groups, water and gas chemistry in both lakes is controlled by the same prokaryotic functions, especially regarding the CO2-CH4 cycle. Addition of hydrothermal CO2 through the bottom of the lakes plays a fundamental priming role in developing a stable water stratification and fuelling anoxic bacterial and archaeal populations. Methanogens and methane oxidizers as well as autotrophic and heterotrophic aerobic bacteria responsible of organic carbon recycling resulted to be stratified with depth and strictly related to the chemical-physical conditions and availability of free oxygen, affecting both the CO2 and CH4 chemical concentrations and their isotopic compositions along the water column. Hule and Río Cuarto lakes were demonstrated to contain a CO2 (CH4, N2)-rich gas reservoir mainly controlled by the interactions occurring between geosphere and biosphere. Thus, we introduced the term of bio-activity volcanic lakes to distinguish these lakes, which have analogues worldwide (e.g. Kivu: D.R.C.-Rwanda; Albano, Monticchio and Averno: Italy; Pavin: France) from volcanic lakes only characterized by geogenic CO2 reservoir such as Nyos and Monoun (Cameroon). PMID

  8. A statistical method linking geological and historical eruption time series for volcanic hazard estimations: Applications to active polygenetic volcanoes

    Science.gov (United States)

    Mendoza-Rosas, Ana Teresa; De la Cruz-Reyna, Servando

    2008-09-01

    The probabilistic analysis of volcanic eruption time series is an essential step for the assessment of volcanic hazard and risk. Such series describe complex processes involving different types of eruptions over different time scales. A statistical method linking geological and historical eruption time series is proposed for calculating the probabilities of future eruptions. The first step of the analysis is to characterize the eruptions by their magnitudes. As is the case in most natural phenomena, lower magnitude events are more frequent, and the behavior of the eruption series may be biased by such events. On the other hand, eruptive series are commonly studied using conventional statistics and treated as homogeneous Poisson processes. However, time-dependent series, or sequences including rare or extreme events, represented by very few data of large eruptions require special methods of analysis, such as the extreme-value theory applied to non-homogeneous Poisson processes. Here we propose a general methodology for analyzing such processes attempting to obtain better estimates of the volcanic hazard. This is done in three steps: Firstly, the historical eruptive series is complemented with the available geological eruption data. The linking of these series is done assuming an inverse relationship between the eruption magnitudes and the occurrence rate of each magnitude class. Secondly, we perform a Weibull analysis of the distribution of repose time between successive eruptions. Thirdly, the linked eruption series are analyzed as a non-homogeneous Poisson process with a generalized Pareto distribution as intensity function. As an application, the method is tested on the eruption series of five active polygenetic Mexican volcanoes: Colima, Citlaltépetl, Nevado de Toluca, Popocatépetl and El Chichón, to obtain hazard estimates.

  9. Geosphere-biosphere interactions in bio-activity volcanic lakes: evidences from Hule and Rio Cuarto (Costa Rica.

    Directory of Open Access Journals (Sweden)

    Jacopo Cabassi

    Full Text Available Hule and Río Cuarto are maar lakes located 11 and 18 km N of Poás volcano along a 27 km long fracture zone, in the Central Volcanic Range of Costa Rica. Both lakes are characterized by a stable thermic and chemical stratification and recently they were affected by fish killing events likely related to the uprising of deep anoxic waters to the surface caused by rollover phenomena. The vertical profiles of temperature, pH, redox potential, chemical and isotopic compositions of water and dissolved gases, as well as prokaryotic diversity estimated by DNA fingerprinting and massive 16S rRNA pyrosequencing along the water column of the two lakes, have highlighted that different bio-geochemical processes occur in these meromictic lakes. Although the two lakes host different bacterial and archaeal phylogenetic groups, water and gas chemistry in both lakes is controlled by the same prokaryotic functions, especially regarding the CO2-CH4 cycle. Addition of hydrothermal CO2 through the bottom of the lakes plays a fundamental priming role in developing a stable water stratification and fuelling anoxic bacterial and archaeal populations. Methanogens and methane oxidizers as well as autotrophic and heterotrophic aerobic bacteria responsible of organic carbon recycling resulted to be stratified with depth and strictly related to the chemical-physical conditions and availability of free oxygen, affecting both the CO2 and CH4 chemical concentrations and their isotopic compositions along the water column. Hule and Río Cuarto lakes were demonstrated to contain a CO2 (CH4, N2-rich gas reservoir mainly controlled by the interactions occurring between geosphere and biosphere. Thus, we introduced the term of bio-activity volcanic lakes to distinguish these lakes, which have analogues worldwide (e.g. Kivu: D.R.C.-Rwanda; Albano, Monticchio and Averno: Italy; Pavin: France from volcanic lakes only characterized by geogenic CO2 reservoir such as Nyos and Monoun

  10. Assessing the volcanic hazard for Rome: 40Ar/39Ar and In-SAR constraints on the most recent eruptive activity and present-day uplift at Colli Albani Volcanic District

    Science.gov (United States)

    Marra, F.; Gaeta, M.; Giaccio, B.; Jicha, B. R.; Palladino, D. M.; Polcari, M.; Sottili, G.; Taddeucci, J.; Florindo, F.; Stramondo, S.

    2016-07-01

    We present new 40Ar/39Ar data which allow us to refine the recurrence time for the most recent eruptive activity occurred at Colli Albani Volcanic District (CAVD) and constrain its geographic area. Time elapsed since the last eruption (36 kyr) overruns the recurrence time (31 kyr) in the last 100 kyr. New interferometric synthetic aperture radar data, covering the years 1993-2010, reveal ongoing inflation with maximum uplift rates (>2 mm/yr) in the area hosting the most recent (<200 ka) vents, suggesting that the observed uplift might be caused by magma injection within the youngest plumbing system. Finally, we frame the present deformation within the structural pattern of the area of Rome, characterized by 50 m of regional uplift since 200 ka and by geologic evidence for a recent (<2000 years) switch of the local stress-field, highlighting that the precursors of a new phase of volcanic activity are likely occurring at the CAVD.

  11. A Decade of Volcanic Observations from Aura and the A-Train

    Science.gov (United States)

    Carn, Simon A.; Krotkov, Nickolay Anatoly; Yang, Kai; Krueger, Arlin J.; Hughes, Eric J.; Wang, Jun; Flower, Verity; Telling, Jennifer

    2014-01-01

    Aura observations have made many seminal contributions to volcanology. Prior to the Aura launch, satellite observations of volcanic degassing (e.g., from TOMS) were mostly restricted to large eruptions. However, the vast majority of volcanic gases are released during quiescent 'passive' degassing between eruptions. The improved sensitivity of Aura OMI permitted the first daily, space-borne measurements of passive volcanic SO2 degassing, providing improved constraints on the source locations and magnitude of global SO2 emissions for input to atmospheric chemistry and climate models. As a result of this unique sensitivity to volcanic activity, OMI data were also the first satellite SO2 measurements to be routinely used for volcano monitoring at several volcano observatories worldwide. Furthermore, the Aura OMI SO2 data also offer unprecedented sensitivity to volcanic clouds in the UTLS, elucidating the transport, fate and lifetime of volcanic SO2 and providing critical input to aviation hazard mitigation efforts. Another major advance has been the improved vertical resolution of volcanic clouds made possible by synergy between Aura and other A-Train instruments (e.g., AIRS, CALIPSO, CloudSat), advanced UV SO2 altitude retrievals, and inverse trajectory modeling of detailed SO2 cloud maps. This altitude information is crucial for climate models and aviation hazards. We will review some of the highlights of a decade of Aura observations of volcanic activity and look ahead to the future of volcanic observations from space.

  12. How consumer physical activity monitors could transform human physiology research.

    Science.gov (United States)

    Wright, Stephen P; Hall Brown, Tyish S; Collier, Scott R; Sandberg, Kathryn

    2017-03-01

    A sedentary lifestyle and lack of physical activity are well-established risk factors for chronic disease and adverse health outcomes. Thus, there is enormous interest in measuring physical activity in biomedical research. Many consumer physical activity monitors, including Basis Health Tracker, BodyMedia Fit, DirectLife, Fitbit Flex, Fitbit One, Fitbit Zip, Garmin Vivofit, Jawbone UP, MisFit Shine, Nike FuelBand, Polar Loop, Withings Pulse O2, and others have accuracies similar to that of research-grade physical activity monitors for measuring steps. This review focuses on the unprecedented opportunities that consumer physical activity monitors offer for human physiology and pathophysiology research because of their ability to measure activity continuously under real-life conditions and because they are already widely used by consumers. We examine current and potential uses of consumer physical activity monitors as a measuring or monitoring device, or as an intervention in strategies to change behavior and predict health outcomes. The accuracy, reliability, reproducibility, and validity of consumer physical activity monitors are reviewed, as are limitations and challenges associated with using these devices in research. Other topics covered include how smartphone apps and platforms, such as the Apple ResearchKit, can be used in conjunction with consumer physical activity monitors for research. Lastly, the future of consumer physical activity monitors and related technology is considered: pattern recognition, integration of sleep monitors, and other biosensors in combination with new forms of information processing.

  13. Volcanism on Mars. Chapter 41

    Science.gov (United States)

    Zimbelman, J. R.; Garry, W. B.; Bleacher, J. E.; Crown, D. A.

    2015-01-01

    Spacecraft exploration has revealed abundant evidence that Mars possesses some of the most dramatic volcanic landforms found anywhere within the solar system. How did a planet half the size of Earth produce volcanoes like Olympus Mons, which is several times the size of the largest volcanoes on Earth? This question is an example of the kinds of issues currently being investigated as part of the space-age scientific endeavor called "comparative planetology." This chapter summarizes the basic information currently known about volcanism on Mars. The volcanoes on Mars appear to be broadly similar in overall morphology (although, often quite different in scale) to volcanic features on Earth, which suggests that Martian eruptive processes are not significantly different from the volcanic styles and processes on Earth. Martian volcanoes are found on terrains of different age, and Martian volcanic rocks are estimated to comprise more than 50% of the Martian surface. This is in contrast to volcanism on smaller bodies such as Earth's Moon, where volcanic activity was mainly confined to the first half of lunar history (see "Volcanism on the Moon"). Comparative planetology supports the concept that volcanism is the primary mechanism for a planetary body to get rid of its internal heat; smaller bodies tend to lose their internal heat more rapidly than larger bodies (although, Jupiter's moon Io appears to contradict this trend; Io's intense volcanic activity is powered by unique gravitational tidal forces within the Jovian system; see "Volcanism on Io"), so that volcanic activity on Mars would be expected to differ considerably from that found on Earth and the Moon.

  14. 3D-Reconstruction of recent volcanic activity from ROV-video, Charles Darwin Seamounts, Cape Verdes

    Science.gov (United States)

    Kwasnitschka, T.; Hansteen, T. H.; Kutterolf, S.; Freundt, A.; Devey, C. W.

    2011-12-01

    As well as providing well-localized samples, Remotely Operated Vehicles (ROVs) produce huge quantities of visual data whose potential for geological data mining has seldom if ever been fully realized. We present a new workflow to derive essential results of field geology such as quantitative stratigraphy and tectonic surveying from ROV-based photo and video material. We demonstrate the procedure on the Charles Darwin Seamounts, a field of small hot spot volcanoes recently identified at a depth of ca. 3500m southwest of the island of Santo Antao in the Cape Verdes. The Charles Darwin Seamounts feature a wide spectrum of volcanic edifices with forms suggestive of scoria cones, lava domes, tuff rings and maar-type depressions, all of comparable dimensions. These forms, coupled with the highly fragmented volcaniclastic samples recovered by dredging, motivated surveying parts of some edifices down to centimeter scale. ROV-based surveys yielded volcaniclastic samples of key structures linked by extensive coverage of stereoscopic photographs and high-resolution video. Based upon the latter, we present our workflow to derive three-dimensional models of outcrops from a single-camera video sequence, allowing quantitative measurements of fault orientation, bedding structure, grain size distribution and photo mosaicking within a geo-referenced framework. With this information we can identify episodes of repetitive eruptive activity at individual volcanic centers and see changes in eruptive style over time, which, despite their proximity to each other, is highly variable.

  15. Nordic monitoring on diet, physical activity and overweight

    DEFF Research Database (Denmark)

    Fagt, Sisse; Andersen, Lene Frost; Anderssen, Sigmund A.;

    In 2007, a Nordic working group was established with the aim to describe a future Nordic monitoring system on diet, physical activity and overweight. The monitoring system should be simple and at relatively low cost. Therefore it has been decided to conduct the moni-toring as a telephone interview...

  16. Volcanology and volcanic activity with a primary focus on potential hazard impacts for the Hawaii geothermal project

    Energy Technology Data Exchange (ETDEWEB)

    Moore, R.B. [Federal Center, Denver, CO (United States); Delaney, P.T. [2255 North Gemini Drive, Flagstaff, AZ (United States); Kauahikaua, J.P. [Geological Survey, Hawaii National Park, HI (United States). Hawaiian Volcano Observatory

    1993-10-01

    This annotated bibliography reviews published references about potential volcanic hazards on the Island of Hawaii that are pertinent to drilling and operating geothermal wells. The first two sections of this annotated bibliography list the most important publications that describe eruptions of Kilauea volcano, with special emphasis on activity in and near the designated geothermal subzones. References about historic eruptions from Mauna Loa`s northeast rift zone, as well as the most recent activity on the southern flank of dormant Mauna Kea, adjacent to the Humu`ula Saddle are described. The last section of this annotated bibliography lists the most important publications that describe and analyze deformations of the surface of Kilauea and Mauna Loa volcanoes.

  17. Quantitative Flow Morphology, Recent Volcanic Evolution and Future Activity of the Kameni Islands, Santorini, Greece

    Science.gov (United States)

    Elliott, J. R.; Pyle, D. M.

    2005-12-01

    The fundamental importance of careful field investigation, and the long term value of detailed published volcanic eruption reports, means that much can be learned about eruption processes even many decades after an eruption has ceased. We illustrate this with reference to the young dacite lava flows of the Kameni islands, Santorini. We have created a new, high resolution digital elevation model (DEM) for the intra-caldera Kameni islands, Santorini, based on new data from a recent airborne laser-ranging (LiDAR) and aerial photography mission. This DEM reveals a wealth of surface morphological information on the dacite lava flows that comprise the Kameni islands. When combined with a re-analysis of contemporary eruption accounts, these data yield important insights into the physical properties and flow behaviour of dacite magma during slow effusive eruptions. Kameni island lava flows exhibit the classic surface morphologies associated with viscous aa: levees, and compression folds. Levee heights and flow widths are consistent with a Bingham rheology, and lava yield strengths of (3 to 7)× 104 Pa. Analysis of the shapes of flow edges confirms that the blocky aa dacite lava flows show a scale-invariant morphology with a typical fractal dimension that is indistinguishable from Hawaiian aa. Dome-growth rates during eruptions of the Kameni islands in 1866 and 1939 are consistent with a model of slow inflation of a dome with a strong crust. Lava domes on the Kameni islands have a crustal yield strength (4×107 Pa) that is lower by a factor of 2 to 4 than the domes at Pinatubo and Mount St Helens. The dome height model, combined with the apparent time-predictable nature of volcanic eruptions of the Kameni islands, allows us to predict that the next eruption of the Kameni islands will last for > 2.6 years (in 2005) and will involve formation of a dome ca. 115 to 123 m high.

  18. California's Vulnerability to Volcanic Hazards: What's at Risk?

    Science.gov (United States)

    Mangan, M.; Wood, N. J.; Dinitz, L.

    2015-12-01

    California is a leader in comprehensive planning for devastating earthquakes, landslides, floods, and tsunamis. Far less attention, however, has focused on the potentially devastating impact of volcanic eruptions, despite the fact that they occur in the State about as frequently as the largest earthquakes on the San Andreas Fault Zone. At least 10 eruptions have occurred in the past 1,000 years—most recently in northern California (Lassen Peak 1914 to 1917)—and future volcanic eruptions are inevitable. The likelihood of renewed volcanism in California is about one in a few hundred to one in a few thousand annually. Eight young volcanoes, ranked as Moderate to Very High Threat [1] are dispersed throughout the State. Partially molten rock (magma) resides beneath at least seven of these—Medicine Lake Volcano, Mount Shasta, Lassen Volcanic Center, Clear Lake Volcanic Field, Long Valley Volcanic Region, Coso Volcanic Field, and Salton Buttes— causing earthquakes, toxic gas emissions, hydrothermal activity, and (or) ground deformation. Understanding the hazards and identifying what is at risk are the first steps in building community resilience to volcanic disasters. This study, prepared in collaboration with the State of California Governor's Office of Emergency Management and the California Geological Survey, provides a broad perspective on the State's exposure to volcano hazards by integrating mapped volcano hazard zones with geospatial data on at-risk populations, infrastructure, and resources. The study reveals that ~ 16 million acres fall within California's volcano hazard zones, along with ~ 190 thousand permanent and 22 million transitory populations. Additionally, far-field disruption to key water delivery systems, agriculture, utilities, and air traffic is likely. Further site- and sector-specific analyses will lead to improved hazard mitigation efforts and more effective disaster response and recovery. [1] "Volcanic Threat and Monitoring Capabilities

  19. Active spreading processes at ultraslow mid-ocean ridges: The 1999-2001 seismo-volcanic episode at 85°E Gakkel ridge, Arctic Ocean

    Science.gov (United States)

    Schlindwein, Vera; Riedel, Carsten; Korger, Edith; Läderach, Christine

    2010-05-01

    The rate of magma and crustal production at mid-ocean ridges is thought to decrease with decreasing spreading rate. At ultraslow spreading rates below 10-20 mm/y full rate, heat loss by conduction greatly reduces melt production with less melt produced at increasingly greater depths. Gakkel Ridge, the actively spreading mid-ocean ridge in the Arctic Ocean, opens at rates of 14 mm/y in the west decreasing to less than 6 mm/y at its eastern termination and demonstrates that magma production is not only a function of spreading rate. Whereas amagmatic spreading takes place at rates of about 12-10 mm/y, focussed melt production occurs at even lower spreading rates in long-lived discrete volcanic centres. One such centre is the 85°E volcanic complex at eastern Gakkel ridge where in 1999 a teleseismically recorded earthquake swarm consisting of more than 250 earthquakes over 9 months signalled the onset of an active spreading episode. The earthquake swarm is believed to be associated with volcanic activity although no concurrent lava effusion was found. We analysed the teleseismic earthquake swarm together with visual observation and microseismic data recorded at this site in 2001 and 2007 and noted the following characteristics which may be indicative for volcanic spreading events at the still poorly explored ultraslow spreading ridges: - unusual duration: The 1999 earthquake swarm lasted over 9 months rather than a few weeks as observed on faster spreading ridges. In addition, in 2001 seismoacoustic sounds which we interpret as gas discharge in Strombolian eruptions and a giant event plume maintained over more than one year indicate waxing and waning volcanic activity since 1999. - unusual strength: The earthquake swarm was detected at teleseismic distances of more than 1000 km and included 11 events with a magnitude >5. No other confirmed mid-ocean ridge eruption released a comparable seismic moment. Rather than focussing in a narrow area or showing pronounced

  20. Fluid escape structures in the Graham Bank region (Sicily Channel, Central Mediterranean) revealing volcanic and neotectonic activity.

    Science.gov (United States)

    Spatola, Daniele; Pennino, Valentina; Basilone, Luca; Interbartolo, Francesco; Micallef, Aaron; Sulli, Attilio; Basilone, Walter

    2016-04-01

    In the Sicily Channel, (Central Mediterranean), two geodynamic processes overlap each other, the Maghrebides-Apennines accretionary prism and the Sicily Channel rift. Moreover, the northwestern sector (Banks sector) is characterised by an irregular seafloor morphology linked to the recent volcanic and tectonic activity.In order to discriminate the role exerted by both the processes in the morphostructural setting of the area we used a dataset of both high and very high resolution single-channel and multi-channel profiles, acquired in the frame of the RITMARE project respectively with CHIRP and sparker, and airgun sources, and high resolution (5 m cell) morpho-bathymetric data. The data allowed us to identify and characterise two areas where different geological features (sedimentary and volcanic) are prevailing. They present fluid escaping evidence, which often appears to be active and generating different types of morphologies (both positive and negative). In the western sector we recognised pockmarks at water depths of 195 to 317 m, with diameters from 25 to 580 m, depths from 1.3 to 15 m, and slope up to 23°. They show sub-circular shape in plan-view and reflectors with upward concavity in cross section, and are oriented along a NW-SE trend.The CHIRP and multichannel profiles highlight fluids that affect the Plio-Quaternary succession, especially in areas where the top surface of the Messinian succession is shallower. Conversely, wipe-out acoustic facies were recognised in proximity of: i) extensional faults of Mesozoic age with NW-SE trend; ii) dip/strike slip faults of Cenozoic age with NW-SE, N-S and about NNE-SSW trends, and iii) extensional neo-tectonic faults with NW-SE and NNW-SSE trends. We cannot exclude that they could feed the shallower reservoir producing a mixing between the two. In the eastern sector we recognised a cluster of volcanoes composed of seven cone-shaped structures (SCV1-7), pertaining to a wide area known as Graham Bank. A detailed

  1. Characteristics of suspended sediment and river discharge during the beginning of snowmelt in volcanically active mountainous environments

    Science.gov (United States)

    Mouri, Goro; Ros, Faizah Che; Chalov, Sergey

    2014-05-01

    To better understand instream suspended sediment delivery and transformation processes, we conducted field measurements and laboratory experiments to study the natural function of spatial and temporal variation, sediment particles, stable isotopes, particle size, and aspect ratio from tributary to mainstream flows of the Sukhaya Elizovskaya River catchment at the beginning of and during snowmelt. The Sukhaya Elizovskaya River is located in the Kamchatka Peninsula of Russia and is surrounded by active volcanic territory. The study area has a range of hydrological features that determine the extreme amounts of washed sediments. Sediment transported to the river channels in volcanic mountainous terrain is believed to be strongly influenced by climate conditions, particularly when heavy precipitation and warmer climate trigger mudflows in association with the melting snow. The high porosity of the channel bottom material also leads to interactions with the surface water, causing temporal variability in the daily fluctuations in water and sediment flow. Field measurements revealed that suspended sediment behaviour and fluxes decreased along the mainstream Sukhaya Elizovskaya River from inflows from a tributary catchment located in the volcanic mountain range. In laboratory experiments, water samples collected from tributaries were mixed with those from the mainstream flow of the Sukhaya Elizovskaya River to examine the cause of debris flow and characteristics of suspended sediment in the mainstream. These findings and the geological conditions of the tributary catchments studied led us to conclude that halloysite minerals likely comprise the majority of suspended sediments and play a significant role in phosphate adsorption. The experimental results were upscaled and verified using field measurements. Our results indicate that the characteristics of suspended sediment and river discharge in the Sukhaya Elizovskaya River can be attributed primarily to the beginning of

  2. Instructional physical activity monitor video in english and spanish

    Science.gov (United States)

    The ActiGraph activity monitor is a widely used method for assessing physical activity. Compliance with study procedures in critical. A common procedure is for the research team to meet with participants and demonstrate how and when to attach and remove the monitor and convey how many wear-days are ...

  3. Monitoring bat activity at the Dutch EEZ in 2014

    NARCIS (Netherlands)

    Lagerveld, S.; Jonge Poerink, B.; Vries, de P.

    2015-01-01

    IMARES conducted studies in 2012 and 2013 to monitor offshore bat activity with passive acoustic ultrasonic recorders. In the follow-up project reported here, more data on the offshore occurrence of bats was collected in 2014. Using the same methodology as in 2012 and 2013, bat activity was monitore

  4. Light-noble-gas isotopic ratios in gases from Mt. Etna (Southern Italy). Implications for mantle contamination and volcanic activity

    Energy Technology Data Exchange (ETDEWEB)

    Italiano, F. [Consiglio Nazionale delle Ricerche, Palermo (Italy). Ist. di Geochimica dei Fluidi; Nuccio, P.M. [Palermo Univ., Palermo (Italy). Ist. di Mineralogia, Petrografia e Geochimica; Nakai, S. [Tokyo Univ., Tokyo (Japan). Lab. for Earthquake Chemistry; Wakita, H. [Tokyo Univ., Tokyo (Japan). Earthquake Research Inst.

    1999-08-01

    Taking into account the light-noble-isotopic ratios signature of gas samples coming from the Etnean area (Southern Italy), it seems that in this area the crustal contamination played a minor role. Instead, processes that enriched the original MORB-type mantle in incompatible elements, have to be considered. The {sup 3}He/{sup 4}He ratios are, thus, lowered because of {sup 1}He produced by radioactive decay of U and Th. On the other hand, helium isotopic ratios have shown wide temporal variations sometimes reaching values as high as 7.6 Ra, out pf typical Etnean range. As these unusually high ratios have been measured during phases of unrest of the volcanic activity at Mt. Etna, this apparent discrepancy in the helium isotopic ratios is considered, as the effect of fractionation processes occurred during the magma uprising.

  5. Global positioning system survey data for active seismic and volcanic areas of eastern Sicily, 1994 to 2013

    Science.gov (United States)

    Bonforte, Alessandro; Fagone, Sonia; Giardina, Carmelo; Genovese, Simone; Aiesi, Gianpiero; Calvagna, Francesco; Cantarero, Massimo; Consoli, Orazio; Consoli, Salvatore; Guglielmino, Francesco; Puglisi, Biagio; Puglisi, Giuseppe; Saraceno, Benedetto

    2016-08-01

    This work presents and describes a 20-year long database of GPS data collected by geodetic surveys over the seismically and volcanically active eastern Sicily, for a total of more than 6300 measurements. Raw data were initially collected from the various archives at the Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania—Osservatorio Etneo and organized in a single repository. Here, quality and completeness checks were performed, while all necessary supplementary information were searched, collected, validated and organized together with the relevant data. Once all data and information collections were completed, raw binary data were converted into the universal ASCII RINEX format; all data are provided in this format with the necessary information for precise processing. In order to make the data archive readily consultable, we developed software allowing the user to easily search and obtain the needed data by simple alphanumeric and geographic queries.

  6. Modeling crustal deformation near active faults and volcanic centers: a catalog of deformation models and modeling approaches

    Science.gov (United States)

    Battaglia, Maurizio; ,; Peter, F.; Murray, Jessica R.

    2013-01-01

    This manual provides the physical and mathematical concepts for selected models used to interpret deformation measurements near active faults and volcanic centers. The emphasis is on analytical models of deformation that can be compared with data from the Global Positioning System (GPS) receivers, Interferometric synthetic aperture radar (InSAR), leveling surveys, tiltmeters and strainmeters. Source models include pressurized spherical, ellipsoidal, and horizontal penny-shaped geometries in an elastic, homogeneous, flat half-space. Vertical dikes and faults are described following the mathematical notation for rectangular dislocations in an elastic, homogeneous, flat half-space. All the analytical expressions were verified against numerical models developed by use of COMSOL Multyphics, a Finite Element Analysis software (http://www.comsol.com). In this way, typographical errors present were identified and corrected. Matlab scripts are also provided to facilitate the application of these models.

  7. Global positioning system survey data for active seismic and volcanic areas of eastern Sicily, 1994 to 2013.

    Science.gov (United States)

    Bonforte, Alessandro; Fagone, Sonia; Giardina, Carmelo; Genovese, Simone; Aiesi, Gianpiero; Calvagna, Francesco; Cantarero, Massimo; Consoli, Orazio; Consoli, Salvatore; Guglielmino, Francesco; Puglisi, Biagio; Puglisi, Giuseppe; Saraceno, Benedetto

    2016-08-01

    This work presents and describes a 20-year long database of GPS data collected by geodetic surveys over the seismically and volcanically active eastern Sicily, for a total of more than 6300 measurements. Raw data were initially collected from the various archives at the Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania-Osservatorio Etneo and organized in a single repository. Here, quality and completeness checks were performed, while all necessary supplementary information were searched, collected, validated and organized together with the relevant data. Once all data and information collections were completed, raw binary data were converted into the universal ASCII RINEX format; all data are provided in this format with the necessary information for precise processing. In order to make the data archive readily consultable, we developed software allowing the user to easily search and obtain the needed data by simple alphanumeric and geographic queries.

  8. Improved techniques in data analysis and interpretation of potential fields: examples of application in volcanic and seismically active areas

    Directory of Open Access Journals (Sweden)

    G. Florio

    2002-06-01

    Full Text Available Geopotential data may be interpreted by many different techniques, depending on the nature of the mathematical equations correlating specific unknown ground parameters to the measured data set. The investigation based on the study of the gravity and magnetic anomaly fields represents one of the most important geophysical approaches in the earth sciences. It has now evolved aimed both at improving of known methods and testing other new and reliable techniques. This paper outlines a general framework for several applications of recent techniques in the study of the potential methods for the earth sciences. Most of them are here described and significant case histories are shown to illustrate their reliability on active seismic and volcanic areas.

  9. Quality Assurance Project Plan for Facility Effluent Monitoring Plan activities

    Energy Technology Data Exchange (ETDEWEB)

    Nickels, J.M.

    1991-06-01

    This Quality Assurance Project Plan addresses the quality assurance requirements for the Facility Monitoring Plans of the overall site-wide environmental monitoring plan. This plan specifically applies to the sampling and analysis activities and continuous monitoring performed for all Facility Effluent Monitoring Plan activities conducted by Westinghouse Hanford Company. It is generic in approach and will be implemented in conjunction with the specific requirements of individual Facility Effluent Monitoring Plans. This document is intended to be a basic road map to the Facility Effluent Monitoring Plan documents (i.e., the guidance document for preparing Facility Effluent Monitoring Plans, Facility Effluent Monitoring Plan determinations, management plan, and Facility Effluent Monitoring Plans). The implementing procedures, plans, and instructions are appropriate for the control of effluent monitoring plans requiring compliance with US Department of Energy, US Environmental Protection Agency, state, and local requirements. This Quality Assurance Project Plan contains a matrix of organizational responsibilities, procedural resources from facility or site manuals used in the Facility Effluent Monitoring Plans, and a list of the analytes of interest and analytical methods for each facility preparing a Facility Effluent Monitoring Plan. 44 refs., 1 figs., 2 tabs.

  10. New ground-based lidar enables volcanic CO2 flux measurements.

    Science.gov (United States)

    Aiuppa, Alessandro; Fiorani, Luca; Santoro, Simone; Parracino, Stefano; Nuvoli, Marcello; Chiodini, Giovanni; Minopoli, Carmine; Tamburello, Giancarlo

    2015-09-01

    There have been substantial advances in the ability to monitor the activity of hazardous volcanoes in recent decades. However, obtaining early warning of eruptions remains challenging, because the patterns and consequences of volcanic unrests are both complex and nonlinear. Measuring volcanic gases has long been a key aspect of volcano monitoring since these mobile fluids should reach the surface long before the magma. There has been considerable progress in methods for remote and in-situ gas sensing, but measuring the flux of volcanic CO2-the most reliable gas precursor to an eruption-has remained a challenge. Here we report on the first direct quantitative measurements of the volcanic CO2 flux using a newly designed differential absorption lidar (DIAL), which were performed at the restless Campi Flegrei volcano. We show that DIAL makes it possible to remotely obtain volcanic CO2 flux time series with a high temporal resolution (tens of minutes) and accuracy (volcanic CO2 represents a major step forward in volcano monitoring, and will contribute improved volcanic CO2 flux inventories. Our results also demonstrate the unusually strong degassing behavior of Campi Flegrei fumaroles in the current ongoing state of unrest.

  11. Fiber Bragg grating strain sensors to monitor and study active volcanoes

    Science.gov (United States)

    Sorrentino, Fiodor; Beverini, Nicolò; Carbone, Daniele; Carelli, Giorgio; Francesconi, Francesco; Gambino, Salvo; Giacomelli, Umberto; Grassi, Renzo; Maccioni, Enrico; Morganti, Mauro

    2016-04-01

    Stress and strain changes are among the best indicators of impending volcanic activity. In volcano geodesy, borehole volumetric strain-meters are mostly utilized. However, they are not easy to install and involve high implementation costs. Advancements in opto-electronics have allowed the development of low-cost sensors, reliable, rugged and compact, thus particularly suitable for field application. In the framework of the EC FP7 MED-SUV project, we have developed strain sensors based on the fiber Bragg grating (FBG) technology. In comparison with previous implementation of the FBG technology to study rock deformations, we have designed a system that is expected to offer a significantly higher resolution and accuracy in static measurements and a smooth dynamic response up to 100 Hz, implying the possibility to observe seismic waves. The system performances are tailored to suit the requirements of volcano monitoring, with special attention to power consumption and to the trade-off between performance and cost. Preliminary field campaigns were carried out on Mt. Etna (Italy) using a prototypal single-axis FBG strain sensor, to check the system performances in out-of-the-lab conditions and in the harsh volcanic environment (lack of mains electricity for power, strong diurnal temperature changes, strong wind, erosive ash, snow and ice during the winter time). We also designed and built a FBG strain sensor featuring a multi-axial configuration which was tested and calibrated in the laboratory. This instrument is suitable for borehole installation and will be tested on Etna soon.

  12. Remote Physical Activity Monitoring in Neurological Disease: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Valerie A J Block

    Full Text Available To perform a systematic review of studies using remote physical activity monitoring in neurological diseases, highlighting advances and determining gaps.Studies were systematically identified in PubMed/MEDLINE, CINAHL and SCOPUS from January 2004 to December 2014 that monitored physical activity for ≥24 hours in adults with neurological diseases. Studies that measured only involuntary motor activity (tremor, seizures, energy expenditure or sleep were excluded. Feasibility, findings, and protocols were examined.137 studies met inclusion criteria in multiple sclerosis (MS (61 studies; stroke (41; Parkinson's Disease (PD (20; dementia (11; traumatic brain injury (2 and ataxia (1. Physical activity levels measured by remote monitoring are consistently low in people with MS, stroke and dementia, and patterns of physical activity are altered in PD. In MS, decreased ambulatory activity assessed via remote monitoring is associated with greater disability and lower quality of life. In stroke, remote measures of upper limb function and ambulation are associated with functional recovery following rehabilitation and goal-directed interventions. In PD, remote monitoring may help to predict falls. In dementia, remote physical activity measures correlate with disease severity and can detect wandering.These studies show that remote physical activity monitoring is feasible in neurological diseases, including in people with moderate to severe neurological disability. Remote monitoring can be a psychometrically sound and responsive way to assess physical activity in neurological disease. Further research is needed to ensure these tools provide meaningful information in the context of specific neurological disorders and patterns of neurological disability.

  13. Characterization of the volcanic eruption emissions using neutron activation analysis; Caracterizacion de las emisiones de una erupcion volcanica mediante analisis por activacion neutronica

    Energy Technology Data Exchange (ETDEWEB)

    Pla, Rita R. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina). Radioquimica, Tecnicas Analiticas Nucleares; Tafuri, Victoria V. [Servicio Meteorologico Nacional, Buenos Aires (Argentina). Centro de Contaminacion del Aire

    1997-10-01

    Characterization of the volcanic particulate material has been performed by analyzing aerosols and ashes with instrumental neutron activation analysis. Crustal enrichment factors were calculated using the elemental concentration and clustering techniques, and multivariate analysis were done. The analytical and data treatment methodologies allowed the sample differentiation from their geographical origin viewpoint, based on their chemical composition patterns, which are related to the deposit formation processes, which consist of direct deposition from the volcanic cloud, and removal by wind action after the end of the eruption, and and finally the deposition. (author). 8 refs., 5 figs.

  14. Precambrian Lunar Volcanic Protolife

    Directory of Open Access Journals (Sweden)

    Jack Green

    2009-06-01

    Full Text Available Five representative terrestrial analogs of lunar craters are detailed relevant to Precambrian fumarolic activity. Fumarolic fluids contain the ingredients for protolife. Energy sources to derive formaldehyde, amino acids and related compounds could be by flow charging, charge separation and volcanic shock. With no photodecomposition in shadow, most fumarolic fluids at 40 K would persist over geologically long time periods. Relatively abundant tungsten would permit creation of critical enzymes, Fischer-Tropsch reactions could form polycyclic aromatic hydrocarbons and soluble volcanic polyphosphates would enable assembly of nucleic acids. Fumarolic stimuli factors are described. Orbital and lander sensors specific to protolife exploration including combined Raman/laser-induced breakdown spectrocsopy are evaluated.

  15. Future developments in modelling and monitoring of volcanic ash clouds: outcomes from the first IAVCEI-WMO workshop on Ash Dispersal Forecast and Civil Aviation

    Science.gov (United States)

    Bonadonna, Costanza; Folch, Arnau; Loughlin, Susan; Puempel, Herbert

    2012-01-01

    As a result of the serious consequences of the 2010 Eyjafjallajökull eruption (Iceland) on civil aviation, 52 volcanologists, meteorologists, atmospheric dispersion modellers and space and ground-based monitoring specialists from 12 different countries (including representatives from 6 Volcanic Ash Advisory Centres and related institutions) gathered to discuss the needs of the ash dispersal modelling community, investigate new data-acquisition strategies (i.e. quantitative measurements and observations) and discuss how to improve communication between the research community and institutions with an operational mandate. Based on a dedicated benchmark exercise and on 3 days of in-depth discussion, recommendations have been made for future model improvements, new strategies of ash cloud forecasting, multidisciplinary data acquisition and more efficient communication between different communities. Issues addressed in the workshop include ash dispersal modelling, uncertainty, ensemble forecasting, combining dispersal models and observations, sensitivity analysis, model variability, data acquisition, pre-eruption forecasting, first simulation and data assimilation, research priorities and new communication strategies to improve information flow and operational routines. As a main conclusion, model developers, meteorologists, volcanologists and stakeholders need to work closely together to develop new and improved strategies for ash dispersal forecasting and, in particular, to: (1) improve the definition of the source term, (2) design models and forecasting strategies that can better characterize uncertainties, (3) explore and identify the best ensemble strategies that can be adapted to ash dispersal forecasting, (4) identify optimized strategies for the combination of models and observations and (5) implement new critical operational strategies.

  16. A quantitative model for volcanic hazard assessment

    OpenAIRE

    W. Marzocchi; Sandri, L.; Furlan, C

    2006-01-01

    Volcanic hazard assessment is a basic ingredient for risk-based decision-making in land-use planning and emergency management. Volcanic hazard is defined as the probability of any particular area being affected by a destructive volcanic event within a given period of time (Fournier d’Albe 1979). The probabilistic nature of such an important issue derives from the fact that volcanic activity is a complex process, characterized by several and usually unknown degrees o...

  17. Monitoring of FR Cnc Flaring Activity

    CERN Document Server

    Golovin, A; Pavlenko, E; Kuznyetsova, Yu; Krushevska, V; Sergeev, A

    2007-01-01

    Being excited by the detection of the first ever-observed optical flare in FR Cnc, we decided to continue photometrical monitoring of this object. The observations were carried out at Crimean Astrophysical Observatory (Crimea, Ukraine; CrAO - hereafter) and at the Terskol Observatory (Russia, Northern Caucasus). The obtained lightcurves are presented and discussed. No distinguishable flares were detected that could imply that flares on FR Cnc are very rare event.

  18. An Interactive Geospatial Database and Visualization Approach to Early Warning Systems and Monitoring of Active Volcanoes: GEOWARN

    Science.gov (United States)

    Gogu, R. C.; Schwandner, F. M.; Hurni, L.; Dietrich, V. J.

    2002-12-01

    Large parts of southern and central Europe and the Pacific rim are situated in tectonically, seismic and volcanological extremely active zones. With the growth of population and tourism, vulnerability and risk towards natural hazards have expanded over large areas. Socio-economical aspects, land use, tourist and industrial planning as well as environmental protection increasingly require needs of natural hazard assessment. The availability of powerful and reliable satellite, geophysical and geochemical information and warning systems is therefore increasingly vital. Besides, once such systems have proven to be effective, they can be applied for similar purposes in other European areas and worldwide. Technologies today have proven that early warning of volcanic activity can be achieved by monitoring measurable changes in geophysical and geochemical parameters. Correlation between different monitored data sets, which would improve any prediction, is very scarce or missing. Visualisation of all spatial information and integration into an "intelligent cartographic concept" is of paramount interest in order to develop 2-, 3- and 4-dimensional models to approach the risk and emergency assessment as well as environmental and socio-economic planning. In the framework of the GEOWARN project, a database prototype for an Early Warning System (EWS) and monitoring of volcanic activity in case of hydrothermal-explosive and volcanic reactivation has been designed. The platform-independent, web-based, JAVA-programmed, interactive multidisciplinary multiparameter visualization software being developed at ETH allows expansion and utilization to other volcanoes, world-wide databases of volcanic unrest, or other types of natural hazard assessment. Within the project consortium, scientific data have been acquired on two pilot sites: Campi Flegrei (Italy) and Nisyros Greece, including 2&3D Topography and Bathymetry, Elevation (DEM) and Landscape models (DLM) derived from conventional

  19. Monitoring activities review of the Radiological Environmental Surveillance Program

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, P.D.

    1992-03-01

    The 1992 Monitoring Activities Review (MAR) is directed at the Radiological Environment Surveillance Program (RESP) activities at the Radioactive Waste Management Complex (RWMC) of Idaho Engineering Laboratory (INEL). MAR panelists studied RESP documents and discussed their concerns with Environmental Monitoring Unit (EMU) staff and other panel members. These concerns were subsequently consolidated into a collection of recommendations with supporting discussions. Recommendations focus on specific monitoring activities, as well as the overall program. The MAR report also contains pertinent comments that should not require further action.

  20. [The sociological monitoring as a tool to evaluate preventive activities].

    Science.gov (United States)

    Mazus, A I; Leven, I I; Vinogradova, O V; Zelenev, V V; Makarenko, O V

    2009-01-01

    The monitoring of conditions of HIV-infection spreading includes qualitative research methods to reveal specified information from people relating immediately to the problem of HIV-infection prevalence. The acquired information can be used both for monitoring of the conditions of HIV-infection spreading (morbidity, prevalence, mortality) and adjustment of preventive activities at the level of specific administrative territory.

  1. DEVELOPMENT ANALYZERS TRANSACTIONS IN MONITORING THE BUSINESS ACTIVITIES OF ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    L. E. Sovik

    2013-01-01

    Full Text Available In the article there are marked the features and prerequisites of implementation in food production technologies devoted to monitor business activity in the realtime. The methodical approach to the development of analyzers transactional business processes of the organization is offered, monitoring scheme for one of the basic types of business events in the procurement process is constructed.

  2. Brain Activity Monitoring for Assessing Satisfaction

    Directory of Open Access Journals (Sweden)

    Paola Johanna Rodríguez Carrillo

    2015-06-01

    Full Text Available Satisfaction is a dimension of usability for which quantitative metrics cannot be calculated during user interactions. Measurement is subjective and depends on the ability to interpret questionnaires and on the memory of the user. This paper represents an attempt to develop an automatic quantitative metric of satisfaction, developed using a Brain Computer Interface to monitor the mental states (Attention/Meditation of users. Based on these results, we are able to establish a correlation between the state of Attention and the users' level of satisfaction.

  3. Role of Social Media and Networking in Volcanic Crises and Communication

    Science.gov (United States)

    Sennert, S.; Klemetti, E. W.; Bird, D. K.

    2016-12-01

    The growth of social media as a primary and often preferred news source has led to the rapid dissemination of information about volcanic eruptions and potential volcanic crises as they begin, evolve, and end. This information comes from a variety of sources: news organisations, emergency management personnel, individuals (both members of the public and official representatives), and volcano monitoring agencies. Once posted, this information is easily shared, increasing the reach to a much broader population than more traditional forms of media, such as radio and newspapers. The onset and popularity of social media as a vehicle for dissemination of eruption information points toward the need to systematically incorporate social media into the official channels that volcano observatories use to distribute activity statements, forecasts, and images. We explore two examples of projects that collect/disseminate information regarding volcanic crises and eruptive activity via social media sources; the Smithsonian/USGS Weekly Volcanic Activity Report (WVAR), which summarizes new and on-going volcanic activity globally and on a weekly basis, and Eruptions, a blog that discusses eruptions as well as other volcanic topics. Based on these experiences, recommendations are made to volcanic observatories in relation to the use of social media as a communication tool. These recommendations include: using social media as a two-way dialogue to communicate and receive information directly from the public and other sources; stating that the social media account is from an official source; and posting types of information that users want to see such as images, videos, and figures.

  4. GlobVolcano pre-operational services for global monitoring active volcanoes

    Science.gov (United States)

    Tampellini, Lucia; Ratti, Raffaella; Borgström, Sven; Seifert, Frank Martin; Peltier, Aline; Kaminski, Edouard; Bianchi, Marco; Branson, Wendy; Ferrucci, Fabrizio; Hirn, Barbara; van der Voet, Paul; van Geffen, J.

    2010-05-01

    The GlobVolcano project (2007-2010) is part of the Data User Element programme of the European Space Agency (ESA). The project aims at demonstrating Earth Observation (EO) based integrated services to support the Volcano Observatories and other mandate users (e.g. Civil Protection) in their monitoring activities. The information services are assessed in close cooperation with the user organizations for different types of volcano, from various geographical areas in various climatic zones. In a first phase, a complete information system has been designed, implemented and validated, involving a limited number of test areas and respective user organizations. In the currently on-going second phase, GlobVolcano is delivering pre-operational services over 15 volcanic sites located in three continents and as many user organizations are involved and cooperating with the project team. The set of GlobVolcano offered EO based information products is composed as follows: Deformation Mapping DInSAR (Differential Synthetic Aperture Radar Interferometry) has been used to study a wide range of surface displacements related to different phenomena (e.g. seismic faults, volcanoes, landslides) at a spatial resolution of less than 100 m and cm-level precision. Permanent Scatterers SAR Interferometry method (PSInSARTM) has been introduced by Politecnico of Milano as an advanced InSAR technique capable of measuring millimetre scale displacements of individual radar targets on the ground by using multi-temporal data-sets, estimating and removing the atmospheric components. Other techniques (e.g. CTM) have followed similar strategies and have shown promising results in different scenarios. Different processing approaches have been adopted, according to data availability, characteristic of the area and dynamic characteristics of the volcano. Conventional DInSAR: Colima (Mexico), Nyiragongo (Congo), Pico (Azores), Areanal (Costa Rica) PSInSARTM: Piton de la Fournaise (La Reunion Island

  5. GOSAT/TANSO-FTS Measurement of Volcanic and Geothermal CO2 Emissions

    Science.gov (United States)

    Schwandner, Florian M.; Carn, Simon A.; Newhall, Christopher G.

    2010-05-01

    Approximately one tenth of the Earth's human population lives in direct reach of volcanic hazards. Being able to provide sufficiently early and scientifically sound warning is a key to volcanic hazard mitigation. Quantitative time-series monitoring of volcanic CO2 emissions will likely play a key role in such early warning activities in the future. Impending volcanic eruptions or any potentially disastrous activity that involves movement of magma in the subsurface, is often preceded by an early increase of CO2 emissions. Conventionally, volcanic CO2 monitoring is done either in campaigns of soil emission measurements (grid of one-time measuring points) that are labor intensive and slow, or by ground-based remote FTIR measurements in emission plumes. These methods are not easily available at all sites of potential activity and prohibitively costly to employ on a large number of volcanoes. In addition, both of these ground-based approaches pose a significant risk to the workers conducting these measurements. Some aircraft-based measurements have been conducted as well in the past, however these are limited by the usually meager funding situation of individual observatories, the hazard such flights pose to equipment and crew, and by the inaccessibility of parts of the plume due to ash hazards. The core motivation for this study is therefore to develop a method for volcanic CO2 monitoring from space that will provide sufficient coverage, resolution, and data quality for an application to quantitative time series monitoring and correlation with other available datasets, from a safe distance and with potentially global reach. In summary, the purpose of the proposed research is to quantify volcanic CO2 emissions using satellite-borne observations. Quantitative estimates will be useful for warning of impending volcanic eruptions, and assessing the contribution of volcanic CO2 to global GHG. Our approach encompasses method development and testing for the detection of

  6. Active Low Intrusion Hybrid Monitor for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Marlon Navia

    2015-09-01

    Full Text Available Several systems have been proposed to monitor wireless sensor networks (WSN. These systems may be active (causing a high degree of intrusion or passive (low observability inside the nodes. This paper presents the implementation of an active hybrid (hardware and software monitor with low intrusion. It is based on the addition to the sensor node of a monitor node (hardware part which, through a standard interface, is able to receive the monitoring information sent by a piece of software executed in the sensor node. The intrusion on time, code, and energy caused in the sensor nodes by the monitor is evaluated as a function of data size and the interface used. Then different interfaces, commonly available in sensor nodes, are evaluated: serial transmission (USART, serial peripheral interface (SPI, and parallel. The proposed hybrid monitor provides highly detailed information, barely disturbed by the measurement tool (interference, about the behavior of the WSN that may be used to evaluate many properties such as performance, dependability, security, etc. Monitor nodes are self-powered and may be removed after the monitoring campaign to be reused in other campaigns and/or WSNs. No other hardware-independent monitoring platforms with such low interference have been found in the literature.

  7. Active Low Intrusion Hybrid Monitor for Wireless Sensor Networks.

    Science.gov (United States)

    Navia, Marlon; Campelo, Jose C; Bonastre, Alberto; Ors, Rafael; Capella, Juan V; Serrano, Juan J

    2015-09-18

    Several systems have been proposed to monitor wireless sensor networks (WSN). These systems may be active (causing a high degree of intrusion) or passive (low observability inside the nodes). This paper presents the implementation of an active hybrid (hardware and software) monitor with low intrusion. It is based on the addition to the sensor node of a monitor node (hardware part) which, through a standard interface, is able to receive the monitoring information sent by a piece of software executed in the sensor node. The intrusion on time, code, and energy caused in the sensor nodes by the monitor is evaluated as a function of data size and the interface used. Then different interfaces, commonly available in sensor nodes, are evaluated: serial transmission (USART), serial peripheral interface (SPI), and parallel. The proposed hybrid monitor provides highly detailed information, barely disturbed by the measurement tool (interference), about the behavior of the WSN that may be used to evaluate many properties such as performance, dependability, security, etc. Monitor nodes are self-powered and may be removed after the monitoring campaign to be reused in other campaigns and/or WSNs. No other hardware-independent monitoring platforms with such low interference have been found in the literature.

  8. Exploring a long-lasting volcanic eruption by means of in-soil radon measurements and seismic activity

    Science.gov (United States)

    Falsaperla, Susanna; Neri, Marco; Di Grazia, Giuseppe; Langer, Horst; Spampinato, Salvatore

    2016-04-01

    We analyze in-soil radon (Rn) emission and ambient parameters (barometric pressure and air temperature measurements) along with seismic activity during the longest flank eruption of this century at Mt. Etna, Italy. This eruption occurred between 14 May 2008 and 6 July 2009, from a N120-140°E eruptive fissure extending between 3050 and 2620 m above sea level. It was heralded by a short-lived (~5 hours) episode of lava fountaining three days before a dike-forming intrusion fed a lava emission, which affected the summit area of the volcano over ~15 months. The peculiar position of the station for the Rn measurement, which was at an altitude of 2950 m above sea level and near (~1 km) the summit active craters, offered us the uncommon chance: i) to explore the temporal development of the gas emission close (relationship between in-soil Rn fluxes and seismic signals (in particular, local earthquakes and volcanic tremor) during the uninterrupted lava emission. This approach reveals important details about the recharging phases characterizing the 2008-2009 eruption, which are not visible with other methods of investigation. Our study benefitted from the application of methods of pattern classification developed in the framework of the European MEDiterrranean Supersite Volcanoes (MED­SUV) project.

  9. "Last mile" challenges to in situ volcanic data transmission

    Directory of Open Access Journals (Sweden)

    J. F. B. D. Fonseca

    2013-08-01

    Full Text Available Scientists play a key role in volcanic risk mitigation, but rely heavily on fast access to data acquired in the vicinity of an active volcano. Hazardous volcanoes are often located in remote areas were telecommunications infrastructure is fragile. Besides being exposed directly to the volcanic hazard, the infrastructure in such remote areas can suffer also from "last mile" limitations derived from lack of market demand for data transmission services. In this paper, we report on the findings of FP7 MIAVITA project in the topic of volcanic data transmission. We draw on the contribution of partners from emergent or developing countries to identify the main bottlenecks and fragilities. We present also the results of an experiment conducted in Fogo island, Cape Verde, to test the availability of VSAT services adequate for volcanic monitoring. We warn against the false sense of security resulting from increasingly ubiquitous connectivity, and point out the lack of reliability of many consumer-type services, particularly during emergencies when such services are likely to crash due to excess of demand from the public. Finally, we propose guidelines and recommend best practices for the design of volcanic monitoring networks in what concerns data transmission. In particular, we advise that the data transmission equipment close to the exposed area should be owned, operated and maintained by the volcanic monitoring institution. We exemplify with the setup of the Fogo telemetric interface, which uses low-power licence-free radio modems to reach a robust point of entry into the public network at a suitable distance from the volcano.

  10. "Last mile" challenges to in situ volcanic data transmission

    Science.gov (United States)

    Fonseca, J. F. B. D.; Faria, B. V. E.; Trindade, J.; Cruz, G.; Chambel, A.; Silva, F. M.; Pereira, R. L.; Vazão, T.

    2013-12-01

    Scientists play a key role in volcanic risk management, but rely heavily on fast access to data acquired in the vicinity of an active volcano. Hazardous volcanoes are often located in remote areas were telecommunications infrastructure is fragile. Besides being exposed directly to the volcanic hazard, the infrastructure in such remote areas can also suffer from "last mile" limitations derived from lack of market demand for data transmission services. In this paper, we report on the findings of the FP7 MIAVITA project in the topic of volcanic data transmission. We draw on the contribution of partners from emergent or developing countries to identify the main bottlenecks and fragilities. We also present the results of an experiment conducted on Fogo Island, Cape Verde, to test the availability of VSAT services adequate for volcanic monitoring. We warn against the false sense of security resulting from increasingly ubiquitous connectivity, and point out the lack of reliability of many consumer-type services, particularly during emergencies when such services are likely to crash due to excess of demand from the public. Finally, we propose guidelines and recommend best practices for the design of volcanic monitoring networks in what concerns data transmission. In particular, we advise that the data transmission equipment close to the exposed area should be owned, operated and maintained by the volcanic monitoring institution. We exemplify with the set-up of the Fogo telemetric interface, which uses low-power licence-free radio modems to reach a robust point of entry into the public network at a suitable distance from the volcano.

  11. The memory of volcanic waters: Shallow magma degassing revealed by halogen monitoring in thermal springs of La Soufrière volcano (Guadeloupe, Lesser Antilles)

    Science.gov (United States)

    Villemant, Benoît; Hammouya, Gilbert; Michel, Agnès; Semet, Michel P.; Komorowski, Jean-Christophe; Boudon, Georges; Cheminée, Jean-Louis

    2005-09-01

    The halogen contents of thermal waters collected since 1979 at La Soufrière volcano (Guadeloupe, Lesser Antilles) are interpreted as a retarded record of magma degassing pulses dispersed into the hydrothermal system. The further the spring is located from the source, the larger the time delay and the older the event recorded in water chemistry. Using advection-dispersion transport models in porous media, we reconstruct the time-series of degassing pulses for the period 1971-1992 and show that it correlates with the seismic records. The 1975-1977 sismo-volcanic crisis at La Soufrière is thereby interpreted as the result of a magma intrusion at shallow depth (˜3 km) which likely began in approximately 1973 and degassed in a pulsatory regime during ˜15 yr. The recent recrudescence of fumarolic and seismic activity could represent the initial stage of new magma injection. Measurement of halogen contents in hydrothermal waters collected around active volcanoes may provide a powerful tool for detection of the initial stages of magma intrusions.

  12. Active imaging for monitoring and technical diagnostics

    Directory of Open Access Journals (Sweden)

    Marek Piszczek

    2014-08-01

    Full Text Available The article presents the results of currently running work in the field of active imaging. The term active refers to both the image acquisition methods, so-called methods of the spatio-temporal framing and active visualization method applying augmented reality. Also results of application of the HMD and 6DoF modules as well as the experimental laser photography device are given. The device works by methods of spatio-temporal framing and it has been developed at the IOE WAT. In terms of image acquisition - active imaging involves the use of illumination of the observed scene. In the field of information visualization - active imaging directly concerns the issues of interaction human-machine environment. The results show the possibility of using the described techniques, among others, rescue (fire brigade, security of mass events (police or the protection of critical infrastructure as well as broadly understood diagnostic problems. Examples presented in the article show a wide range of possible uses of the methods both in observational techniques and measurement. They are relatively innovative solutions and require elaboration of series of hardware and algorithmic issues. However, already at this stage it is clear that active acquisition and visualization methods indicate a high potential for this type of information solutions.[b]Keywords[/b]: active imaging, augmented reality, digital image processing

  13. Seismicity and volcanic activity in Japan based on crustal thermal activity . 2; Chikaku no netsukatsudo ni motozuku Nippon no Jishin kazan katsudo. 2

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, M. [Tokai Univ., Tokyo (Japan). School of Marine Science and Technology

    1996-05-01

    This paper describes the following matters about seismic and volcanic activities in Japan. The previous paper has reported a view that energy is transported from deep portions of the earth`s crust toward outer portions, and the stored energy thrusts up collectively in a certain time period (a rising period). A fact may be accounted for as one of the endorsements thereof that earthquakes and volcanic eruptions take place successively over a wide area from Okinawa to Hokkaido in a short period of time (included in the rising period). When viewed by limiting the time period and areas, a great earthquake would not occur suddenly, but stored energy is released wholly at a certain time while it has been released little by little. Referring to the Kanto Great Earthquake (1923) and the Tokai and Nankai Earthquakes (1944 and 1946), it is found that earthquakes had been occurring successively in the surrounding areas since about 20 years before the occurrence of these great earthquakes. Similar phenomena may be seen in the great earthquakes of Ansei (1854) and An-ei (1707). 5 figs.

  14. Kamchatkan Volcanic Eruption Response Team (KVERT), Russia: preventing the danger of volcanic eruptions to aviation.

    Science.gov (United States)

    Girina, O.; Neal, Ch.

    2012-04-01

    The Kamchatkan Volcanic Eruption Response Team (KVERT) has been a collaborative project of scientists from the Institute of Volcanology and Seismology, the Kamchatka Branch of Geophysical Surveys, and the Alaska Volcano Observatory (IVS, KB GS and AVO). The purpose of KVERT is to reduce the risk of costly, damaging, and possibly deadly encounters of aircraft with volcanic ash clouds. To reduce this risk, KVERT collects all possible volcanic information and issues eruption alerts to aviation and other emergency officials. KVERT was founded by Institute of Volcanic Geology and Geochemistry FED RAS in 1993 (in 2004, IVGG merged with the Institute of Volcanology to become IVS). KVERT analyzes volcano monitoring data (seismic, satellite, visual and video, and pilot reports), assigns the Aviation Color Code, and issues reports on eruptive activity and unrest at Kamchatkan (since 1993) and Northern Kurile (since 2003) volcanoes. KVERT receives seismic monitoring data from KB GS (the Laboratory for Seismic and Volcanic Activity). KB GS maintains telemetered seismic stations to investigate 11 of the most active volcanoes in Kamchatka. Data are received around the clock and analysts evaluate data each day for every monitored volcano. Satellite data are provided from several sources to KVERT. AVO conducts satellite analysis of the Kuriles, Kamchatka, and Alaska as part of it daily monitoring and sends the interpretation to KVERT staff. KVERT interprets MODIS and MTSAT images and processes AVHRR data to look for evidence of volcanic ash and thermal anomalies. KVERT obtains visual volcanic information from volcanologist's field trips, web-cameras that monitor Klyuchevskoy (established in 2000), Sheveluch (2002), Bezymianny (2003), Koryaksky (2009), Avachinsky (2009), Kizimen (2011), and Gorely (2011) volcanoes, and pilots. KVERT staff work closely with staff of AVO, AMC (Airport Meteorological Center) at Yelizovo Airport and the Tokyo Volcanic Ash Advisory Center (VAAC), the

  15. Management plan for Facility Effluent Monitoring Plan activities

    Energy Technology Data Exchange (ETDEWEB)

    Nickels, J.M.; Pratt, D.R.

    1991-08-01

    The DOE/RL 89-19, United States Department of Energy-Richland Operations Office Environmental Protection Implementation Plan (1989), requires the Hanford Site to prepare an Environmental Monitoring Plan (EMP) by November 9, 1991. The DOE/EH-0173T, Environmental Regulatory Guide for Radiological Effluent Monitoring and Environmental Surveillance (1991), provides additional guidance and requires implementation of the EMP within 36 months of the effective data of the rule. DOE Order 5400.1, General Environmental Protection Program, requires each US Department of Energy (DOE) site, facility, or activity that uses, generates, releases, or manages significant quantities of hazardous materials to prepare an EMP. This EMP is to identify and discuss two major activities: (1) effluent monitoring and (2) environmental surveillance. At the Hanford Site, the site-wide EMP will consist of the following elements: (1) A conceptual plan addressing effluent monitoring and environmental surveillance; (2) Pacific Northwest Laboratory (PNL) site-wide environmental surveillance program; (3) Westinghouse Hanford Company (Westinghouse Hanford) effluent monitoring program consisting of the near-field operations environmental monitoring activities and abstracts of each Facility Effluent Monitoring Plan (FEMP). This management plan addresses the third of these three elements of the EMP, the FEMPs.

  16. Evaluation of Activity Recognition Algorithms for Employee Performance Monitoring

    OpenAIRE

    2012-01-01

    Successful Human Resource Management plays a key role in success of any organization. Traditionally, human resource managers rely on various information technology solutions such as Payroll and Work Time Systems incorporating RFID and biometric technologies. This research evaluates activity recognition algorithms for employee performance monitoring. An activity recognition algorithm has been implemented that categorized the activity of employee into following in to classes: job activities and...

  17. Episodes of volcanic activity and their environmental effects in the Okinawa Trough during the last 150 ka

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A piston core Z14-6 was used in this study. The core, 896 cm long, was collected from eastern slope of the Okinawa Trough (27°07′N, 127°27′E, water depth 739m). The δ18O and δ13C values of the sediment bearing planktonic foraminifera G. sacculifer and N. dutertrei were determined; and the abundance of volcanic glass was analyzed. The volcanic glass content high occurred in early stage of polar ice-sheet growth period, or the beginning of cold climate periods corresponding to Milankovitch cycles (Peak Ⅰ, Ⅱ and Ⅴ are corresponding to the beginnings of oxygen isotopic stages 2, 4 and 6, and Peak Ⅲ and Ⅳ are matching oxygen isotopic stage 5b-5d.). It might be possible that volcanic episodes and climate changes were responding to orbital forcing in the Okinawa Trough in late Quaternary. The δ18O difference between N. dutertrei and G. sacculifer shows no clear correlation to the volcanic glass content high, which suggests that the volcanic eruptions did not influence the structure of upper water column. However, the low δ13C difference between G. sacculifer and N. dutertrei is coeval with the volcanic glass high or sub-high content. This fact suggests that volcanic eruptions might influence the reduction in vertical nutritional gradient and carbon cycle process in upper water column. A possible mechanism is that huge quantity of ash and dust had weakened the light intensity, resulting in photosynthesis reduction, productivity decrease, and biological pumping.

  18. The geochemistry of lithium-bearing geothermal water, Taupo Volcanic Zone, and shallow fluid processes in a very active silicic volcanic arc

    Science.gov (United States)

    Dean, A. S.; Hoskin, P. W.; Rudnick, R. L.; Liu, X.; Boseley, C.

    2011-12-01

    The Li abundances and isotopic systematics of Taupo Volcanic Zone (TVZ) geothermal fluids preserves a record of processes occurring within shallow portions of geothermal reservoirs as well as deeper portions of the arc crust. Understanding Li cycling and isotopic fractionation in TVZ geothermal systems contributes to a more refined understanding of physicochemical processes affecting New Zealand's geothermal resources. A comprehensive dataset of 73 samples was compiled, with samples collected from geothermal surface features (springs, spouters, geysers, etc.) and electric-power industry production wells, collectively representing18 geothermal fields across the breadth and width the TVZ. No comparable dataset of fluid analyses exists. Ion chromatography, AAS, and quadrupole ICP-MS analyses were done for Li, Cl-, SiO2, SO42- K, Na, Ca, Mg, B, Sr and Pb concentrations. Lithium abundance in geothermal fluids from the TVZ have a dataset-wide average of 5.9 mg/L and range 4 μg/L to 29 mg/L. The Li abundance and Li/Cl ratios for geothermal water and steam condensates vary systematically as a result of boiling, mixing, and water/rock reaction. Lithium abundance and Li/Cl ratios are, therefore, indicators of shallow (above 2.5 km) and locally variable reservoir processes. δ7Li analysis of 63 samples was performed at the University of Maryland, College Park. Data quality was controlled by measurement of L-SVEC as a calibration standard and by multiple analysis of selected samples. The average δ7Li value for TVZ geothermal fluids is -0.8%. Most δ7Li values for geothermal water fall within a small range of about -3% to+2% indicating similar processes are causing similar isotopic fractionation throughout the region. Considered together, Li aundances and δ7Li values, in combination with numerical models, indicate possible evolution pathways and water/rock reactions in TVZ geothermal systems. Models based on rocks and surface water analysis indicate that Li cycles and

  19. Volcanic activities in the Southern part of East African rift initiation: Melilitites and nephelinites from the Manyara Basin (North Tanzania rift axis)

    Science.gov (United States)

    Baudouin, Celine; Parat, Fleurice; Tiberi, Christel; Gautier, Stéphanie; Peyrat, Sophie

    2016-04-01

    The East African Rift exposes different stages of plate boundary extension, from the initiation of the rift (North (N) Tanzania) to oceanic accretion (Afar). The N Tanzania rift-axis (north-south (S) trend) is divided into 2 different volcanic and seismic activities: (1) the Natron basin (N) with shallow seismicity and intense volcanism and (2) the Manyara basin (S) with deep crustal earthquakes and sparse volcanism. The Natron basin is characterized by extinct volcanoes (2 Ma-0.75 Ma) and active volcano (Oldoinyo Lengai) and a link between seismicity and volcanism has been observed during the Oldoinyo Lengai crisis in 2007. In the S part of the N Tanzanian rift, volcanoes erupted in the Manyara basin between 0.4 and 0.9 Ma. In this study, we used geochemical signature of magmas and deep fluids that percolate into the lithosphere beneath Manyara basin, to define the compositions of magmas and fluids at depth beneath the S part of the N Tanzania rift, compare to the Natron basin and place constrain on the volcanic and seismic activities. The Manyara basin has distinct volcanic activities with mafic magmas as melilitites (Labait) and Mg-nephelinites (carbonatite, Kwaraha), and more differentiated magmas as Mg-poor nephelinites (Hanang). Melilitites and Mg-nephelinites are primary magmas with olivine, clinopyroxene (cpx), and phlogopite recording high-pressure crystallization environment, (melilitites >4 GPa and Mg-nephelinites>1 GPa) with high volatile contents (whole rock: 0.7-4.6 wt% CO2, 0.1-0.3 wt% F and 0.1 wt% Cl). FTIR analyses of olivine constrained the water content of Labait and Kwaraha magmas at 0.1 and 0.4 wt% H2O, respectively. Geochemical modelling suggests that mafic magmas result from a low degree of partial melting (1-2%) of a peridotitic source with garnet and phlogopite (high Tb/Yb (>0.6) and Rb/Sr (0.03-0.12) ratio). Mg-poor nephelinites from Hanang volcano crystallized cpx, Ti-garnet, and nepheline as phenocrysts. Magmas result from fractional

  20. The methodical statutes monitoring of activity by innovative structures

    OpenAIRE

    Stoianovskii, Andrii; Baranovska, Sofia; Stoianovska, Iryna

    2012-01-01

    In the article it is suggested to perfect methodical recommendations in relation to monitoring of activity of innovative structures, which, among other, allow to mark off the results of activity of leading organ of management and contractors of innovative projects, registered in her limits an innovative structure.

  1. Fabric-based integrated energy devices for wearable activity monitors.

    Science.gov (United States)

    Jung, Sungmook; Lee, Jongsu; Hyeon, Taeghwan; Lee, Minbaek; Kim, Dae-Hyeong

    2014-09-01

    A wearable fabric-based integrated power-supply system that generates energy triboelectrically using human activity and stores the generated energy in an integrated supercapacitor is developed. This system can be utilized as either a self-powered activity monitor or as a power supply for external wearable sensors. These demonstrations give new insights for the research of wearable electronics.

  2. The December 2002 volcanic activity at Stromboli: fall and tsunami deposits characterization

    Science.gov (United States)

    Andronico, D.; Coltelli, M.; Corsaro, R. A.; Miraglia, L.; Pompilio, M.

    2003-04-01

    The volcano of Stromboli in the Aeolian Islands (Italy) was known since the Roman age as the "lighthouse" of the Mediterranean Sea, due to its persistent "Strombolian" activity resulting in a summit firelight. During its eruptive history, Stromboli displayed effusive activity and paroxysmal eruptions, too. Lava flows usually flood down the Sciara del Fuoco, a steep depression cutting the NW flank of the cone. Paroxysmals often eject large bombs which can injure the inhabited areas and more rarely form small pyroclastic or debris flows. On the evening of 28 December 2002, effusive activity began after 17 years from the Crater 1; a lava flow reached in about 30 minutes the sea, going down the Sciara del Fuoco. On 30 December, two landslides interested a wide sector of the Sciara del Fuoco, flowing down into the sea. The first one, at about 1.15 p.m., was smaller than the second event which occurred a few minutes later and caused the detachment towards the sea of a more consistent rock volume. This events generated strong tsunami waves which affected the coastline of most of the Aeolian Islands reaching the Milazzo port, about 50 km far. Up to 10 m high waves caused severe damages to the seaside of Stromboli and to the small buildings located at Ficogrande village. We sampled the tsunami sand deposits on the beach and within the houses and the ashes emitted before, and after the tsunami event. The deposits have been studied carrying out grain-size, component analysis, morphometric and compositional characterization. The resulting data allowed to investigate magma fragmentation mechanisms and, for the first time in Stromboli, to characterize the deposit correlated to a tsunami event.

  3. Methane production and consumption in an active volcanic environment of Southern Italy.

    Science.gov (United States)

    Castaldi, Simona; Tedesco, Dario

    2005-01-01

    Methane fluxes were measured, using closed chambers, in the Crater of Solfatara volcano, Campi Flegrei (Southern Italy), along eight transects covering areas of the crater presenting different landscape physiognomies. These included open bare areas, presenting high geothermal fluxes, and areas covered by vegetation, which developed along a gradient from the central open area outwards, in the form of maquis, grassland and woodland. Methane fluxes decreased logarithmically (from 150 to -4.5 mg CH4 m(-2)day(-1)) going from the central part of the crater (fangaia) to the forested edges, similarly to the CO2 fluxes (from 1500 g CO2 m(-2)day(-1) in the centre of the crater to almost zero flux in the woodlands). In areas characterized by high emissions, soil presented elevated temperature (up to 70 degrees C at 0-10 cm depth) and extremely low pH (down to 1.8). Conversely, in woodland areas pH was higher (between 3.7 and 5.1) and soil temperature close to air values. Soil (0-10 cm) was sampled, in two different occasions, along the eight transects, and was tested for methane oxidation capacity in laboratory. Areas covered by vegetation mostly consumed CH4 in the following order woodland>macchia>grassland. Methanotrophic activity was also measured in soil from the open bare area. Oxidation rates were comparable to those measured in the plant covered areas and were significantly correlated with field CH4 emissions. The biological mechanism of uptake was demonstrated by the absence of activity in autoclaved replicates. Thus results suggest the existence of a population of micro-organisms adapted to this extreme environment, which are able to oxidize CH4 and whose activity could be stimulated and supported by elevated concentrations of CH4.

  4. Volcanic Ash Advisory Database, 1983-2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Volcanic ash is a significant hazard to aviation and can also affect global climate patterns. To ensure safe navigation and monitor possible climatic impact, the...

  5. Signs of Recent Volcanism and Hydrothermal Activity Along the Eastern Segment of the Galapagos Spreading Center

    Science.gov (United States)

    Raineault, N.; Smart, C.; Mayer, L. A.; Ballard, R. D.; Fisher, C. R.; Marsh, L.; Shank, T. M.

    2016-12-01

    Since the initial discovery of the Galápagos Spreading Center (GSC) vents in 1977, large-scale disturbances resulting from eruptive and tectonic activity have both destroyed and created vent habitats along the GSC. In 2015, the E/V Nautilus returned to the GSC with remotely operated vehicles (ROVs) to explore 17 kilometers of the rift valley from the Rosebud site in the west, to a previously unexplored temperature anomaly east of the Tempus Fugit vent site. In the years to over a decade since scientists last visited the Rosebud, Rose Garden, and Tempus Fugit sites, there were many changes. Most notably, the Rosebud site, where scientists found a nascent vent community and left site markers in 2002, was apparently covered with glassy basaltic sheet flows. In addition to visual exploration, oceanographic sensor measurements and direct sampling, we used the ROV Hercules imaging suite, comprised of stereo cameras and a structured light laser sensor to map an area of diffuse flow in the Tempus Fugit field (100 m x 150 m). The centimeter-level photographic and bathymetric maps created with this system, along with ROV HD video, samples, and environmental sensors, documented hydrothermal activity and changes in biological community structure (e.g., Riftia tubeworms observed in nascent stages of community development in 2011 were now, in 2015, in greater abundance (with tubes almost 4 m in length). The detection of active venting and associated faunal assemblages will provide insight into the temporal and spatial variability of venting activity at the Tempus Fugit site. On a visual survey of the Rift east of the Tempus Fugit site, extinct sulfide chimney structures were discovered and sampled. There were several chimneys and sulfide deposits in a span of over 8 km that ranged in height from over a half meter to 1.5 m tall. Diffuse flow hosting white and blue bacterial mats was observed near the chimneys complexes. The base of a large chimney structure, venting white fluids

  6. Volcanic hazards and aviation safety

    Science.gov (United States)

    Casadevall, Thomas J.; Thompson, Theodore B.; Ewert, John W.; ,

    1996-01-01

    An aeronautical chart was developed to determine the relative proximity of volcanoes or ash clouds to the airports and flight corridors that may be affected by volcanic debris. The map aims to inform and increase awareness about the close spatial relationship between volcanoes and aviation operations. It shows the locations of the active volcanoes together with selected aeronautical navigation aids and great-circle routes. The map mitigates the threat that volcanic hazards pose to aircraft and improves aviation safety.

  7. Seismic activity and thermal regime of low temperature fumaroles at Mt. Vesuvius in 2004-2011: distinguishing among seismic, volcanic and hydrological signals

    Directory of Open Access Journals (Sweden)

    Paola Cusano

    2013-11-01

    Full Text Available Seismological, soil temperature and hydrological data from Mt. Vesuvius are collected to characterize the present-day activity of the volcanic/hydrothermal system and to detect possible unrest-related phenomena. We present patterns of seismicity and soil temperature in the crater area during the period February 2004-December 2011. The temporal distribution of number and depth of Volcano-Tectonic earthquakes and the energy release are considered. Hourly data of soil temperature have been acquired since January 2004 in different locations along the rim and within the crater. The observed changes of temperature are studied to establish a temporal-based correlation with the volcanic activity and/or with external forcing, as variations of the regional and local stress field acting on the volcano or meteorological phenomena. The comparison between seismic activity and temperature data highlights significant variations possibly related to changes in fluid circulation in the hydrothermal system of the volcano. The common continuous observations start just before a very shallow earthquake occurred in August 2005, which was preceded by a thermal anomaly. This coincidence has been interpreted as related to fluid-driven rock fracturing, as observed in other volcanoes. For the successive temporal patterns, the seismicity rate and energy release are characterized by slight variations accompanied by changes in temperature. This evidence of reactivity of the fumarole thermal field to seismic strain can be used to discriminate between tectonic and volcanic signals at Mt. Vesuvius.

  8. Spatial distribution of Io's volcanic activity from near-IR adaptive optics observations on 100 nights in 2013-2015

    Science.gov (United States)

    de Kleer, Katherine; de Pater, Imke

    2016-12-01

    The extreme and time-variable volcanic activity on Jupiter's moon Io is the result of periodic tidal forcing. The spatial distribution of Io's surface heat flux provides an important constraint on models for tidal heat dissipation, yielding information on interior properties and on the depth at which the tidal heat is primarily dissipated. We analyze the spatial distribution of 48 hot spots based on more than 400 total hot spot detections in adaptive optics images taken on 100 nights in 2013-2015 (data presented in de Kleer and de Pater [2016] Time variability of Io's volcanic activity from near-IR adaptive optics 13 observations on 100 nights in 2013-2015). We present full surface maps of Io at multiple near-infrared wavelengths for three epochs during this time period, and show that the longitudinal distribution of hot spots has not changed significantly since the Galileo mission. We find that hot spots that are persistently active at moderate intensities tend to occur at different latitudes/longitudes than those that exhibit sudden brightening events characterized by high peak intensities and subsequent decay phases. While persistent hot spots are located primarily between ± 30°N, hot spots exhibiting bright eruption events occur primarily between 40° and 65° in both the northern and southern hemispheres. In addition, while persistent hot spots occur preferentially on the leading hemisphere, all bright eruptions were detected on the trailing hemisphere, despite the comparable longitudinal coverage of our observations to both hemispheres. A subset of the bright hot spots which are not intense enough to qualify as outburst eruptions resemble outbursts in terms of temporal evolution and spatial distribution, and may be outbursts whose peak emission went unobserved, or else scaled-down versions of the same phenomenon. A statistical analysis finds that large eruptions are more spatially clustered and occur at higher latitudes than 95% of simulated datasets that

  9. Evaluation of Activity Recognition Algorithms for Employee Performance Monitoring

    Directory of Open Access Journals (Sweden)

    Mehreen Mumtaz

    2012-09-01

    Full Text Available Successful Human Resource Management plays a key role in success of any organization. Traditionally, human resource managers rely on various information technology solutions such as Payroll and Work Time Systems incorporating RFID and biometric technologies. This research evaluates activity recognition algorithms for employee performance monitoring. An activity recognition algorithm has been implemented that categorized the activity of employee into following in to classes: job activities and non-job related activities. Finally, the algorithm will compute the time which employee spent in job related and non-job related activities. This paper presents a novel architecture based upon video analytics that can facilitate Human Resource Managers in real time.

  10. Activity monitoring in sleep research, medicine and psychopharmacology.

    Science.gov (United States)

    Klösch, G; Gruber, G; Anderer, P; Saletu, B

    2001-04-17

    Motor activity as a diagnostic parameter has become an important feature in many fields of medicine and psychology. The concept of mobility and immobility implies the assumption that mental and behaviour disorders involve abnormal activity that can be measured to characterise the disorder itself, to diagnose its presence and to document the impact of treatment. In sleep research, activity monitoring by wrist actigraphs has proven its usefulness as an efficient method to assess the rest-activity cycle over long time periods and to estimate sleep-related features such as sleep efficiency and total sleep time. But like many other techniques and devices, activity monitoring has some limitations and drawbacks. This paper describes the basic features of wrist actigraphy in measuring nocturnal and daytime motor activity.

  11. An overview of existing raptor contaminant monitoring activities in Europe.

    Science.gov (United States)

    Gómez-Ramírez, P; Shore, R F; van den Brink, N W; van Hattum, B; Bustnes, J O; Duke, G; Fritsch, C; García-Fernández, A J; Helander, B O; Jaspers, V; Krone, O; Martínez-López, E; Mateo, R; Movalli, P; Sonne, C

    2014-06-01

    Biomonitoring using raptors as sentinels can provide early warning of the potential impacts of contaminants on humans and the environment and also a means of tracking the success of associated mitigation measures. Examples include detection of heavy metal-induced immune system impairment, PCB-induced altered reproductive impacts, and toxicity associated with lead in shot game. Authorisation of such releases and implementation of mitigation is now increasingly delivered through EU-wide directives but there is little established pan-European monitoring to quantify outcomes. We investigated the potential for EU-wide coordinated contaminant monitoring using raptors as sentinels. We did this using a questionnaire to ascertain the current scale of national activity across 44 European countries. According to this survey, there have been 52 different contaminant monitoring schemes with raptors over the last 50years. There were active schemes in 15 (predominantly western European) countries and 23 schemes have been running for >20years; most monitoring was conducted for >5years. Legacy persistent organic compounds (specifically organochlorine insecticides and PCBs), and metals/metalloids were monitored in most of the 15 countries. Fungicides, flame retardants and anticoagulant rodenticides were also relatively frequently monitored (each in at least 6 countries). Common buzzard (Buteo buteo), common kestrel (Falco tinnunculus), golden eagle (Aquila chrysaetos), white-tailed sea eagle (Haliaeetus albicilla), peregrine falcon (Falco peregrinus), tawny owl (Strix aluco) and barn owl (Tyto alba) were most commonly monitored (each in 6-10 countries). Feathers and eggs were most widely analysed although many schemes also analysed body tissues. Our study reveals an existing capability across multiple European countries for contaminant monitoring using raptors. However, coordination between existing schemes and expansion of monitoring into Eastern Europe is needed. This would enable

  12. Regional Tectonic Framework and Human Activities on the North Central Part of The Mexican Volcanic Belt.

    Science.gov (United States)

    Nieto-Obregon, J.

    2001-12-01

    Faults and fractures northeasterly oriented dipping NW and SE, with slips mainly normal with a slight left lateral component, affect a suite of rocks of Mesozoic to Pleistocene age, in the area of El Bajio, in the states of Queretaro, Guanajuato, Michoacan, and Aguascalientes. The faults and fractures have affected the infrastructure of the cities and surroundings of Queretaro, Celaya, Salamanca, Irapuato, Silao, Leon and Aguascalientes. In the city of Queretaro, the Tlacote-Balvanera active fault has developed a scarp and its motion may potentially affect life lines of great importance. In Celaya City a N-S trending fault traverses the city and has produced a step wise scarp more than 1.80 m high, damaging houses, streets and life lines. In Salamanca, a fault trending N 60oE, dipping to the SE extends from Cerro Gordo to the SW traversing the city and affecting with a varying degree its infrastructure. Displacements observed within the urban area reach as much as 50 cm. Close to Irapuato City, in a quarry near La Valencianita village, a N 45oE trending fault dipping to the NW affects a lacustrine sequence bearing calcareous horizons. The fault exhibits a throw of 10 m and passes north of the urban area. A similarly oriented fault traverses the city of Irapuato, and near the Traffic Circle of Puente de Guadalupe, changes its strike to the SE and continues to the city limits. In the city of Silao, a fault oriented N 60oE, traverses the city and continues to the SW up to the localities of Venta de Ramales and La Aldea. Important displacements in urban and rural areas reach more than 60 cm. Outside the city of Leon in the junction of the highways to Aguascalientes and Guadalajara a normal fault plane NE oriented and dipping SE shows striations compatible with a normal left lateral motion. Faulting is associated with old buried scarps controlled by pre existing faults, and over exploited aquifers. Some of these faults however are considered potentially active based on

  13. Imaging of volcanic activity on Jupiter's moon Io by Galileo during the Galileo Europa Mission and the Galileo Millennium Mission

    Science.gov (United States)

    Keszthelyi, L.; McEwen, A.S.; Phillips, C.B.; Milazzo, M.; Geissler, P.; Turtle, E.P.; Radebaugh, J.; Williams, D.A.; Simonelli, D.P.; Breneman, H.H.; Klaasen, K.P.; Levanas, G.; Denk, T.; Alexander, D.D.A.; Capraro, K.; Chang, S.-H.; Chen, A.C.; Clark, J.; Conner, D.L.; Culver, A.; Handley, T.H.; Jensen, D.N.; Knight, D.D.; LaVoie, S.K.; McAuley, M.; Mego, V.; Montoya, O.; Mortensen, H.B.; Noland, S.J.; Patel, R.R.; Pauro, T.M.; Stanley, C.L.; Steinwand, D.J.; Thaller, T.F.; Woncik, P.J.; Yagi, G.M.; Yoshimizu, J.R.; Alvarez, Del; Castillo, E.M.; Belton, M.J.S.; Beyer, R.; Branston, D.; Fishburn, M.B.; Mueller, B.; Ragan, R.; Samarasinha, N.; Anger, C.D.; Cunningham, C.; Little, B.; Arriola, S.; Carr, M.H.; Asphaug, E.; Moore, J.; Morrison, D.; Rages, K.; Banfield, D.; Bell, M.; Burns, J.A.; Carcich, B.; Clark, B.; Currier, N.; Dauber, I.; Gierasch, P.J.; Helfenstein, P.; Mann, M.; Othman, O.; Rossier, L.; Solomon, N.; Sullivan, R.; Thomas, P.C.; Veverka, J.; Becker, T.; Edwards, K.; Gaddis, L.; Kirk, R.; Lee, E.; Rosanova, T.; Sucharski, R.M.; Beebe, R.F.; Simon, A.; Bender, K.; Chuang, F.; Fagents, S.; Figueredo, P.; Greeley, R.; Homan, K.; Kadel, S.; Kerr, J.; Klemaszewski, J.; Lo, E.; Schwarz, W.; Williams, K.; Bierhaus, E.; Brooks, S.; Chapman, C.R.; Merline, B.; Keller, J.; Schenk, P.; Tamblyn, P.; Bouchez, A.; Dyundian, U.; Ingersoll, A.P.; Showman, A.; Spitale, J.; Stewart, S.; Vasavada, A.; Cunningham, W.F.; Johnson, T.V.; Jones, T.J.; Kaufman, J.M.; Magee, K.P.; Meredith, M.K.; Orton, G.S.; Senske, D.A.; West, A.; Winther, D.; Collins, G.; Fripp, W.J.; Head, J. W.; Pappalardo, R.; Pratt, S.; Procter, L.; Spaun, N.; Colvin, T.; Davies, M.; DeJong, E.M.; Hall, J.; Suzuki, S.; Gorjian, Z.; Giese, B.; Koehler, U.; Neukum, G.; Oberst, J.; Roatsch, T.; Tost, W.; Schuster, P.; Wagner, R.; Dieter, N.; Durda, D.; Greenberg, R.J.; Hoppa, G.; Jaeger, W.; Plassman, J.; Tufts, R.; Fanale, F.P.; Gran,

    2001-01-01

    The Solid-State Imaging (SSI) instrument provided the first high- and medium-resolution views of Io as the Galileo spacecraft closed in on the volcanic body in late 1999 and early 2000. While each volcanic center has many unique features, the majority can be placed into one of two broad categories. The "Promethean" eruptions, typified by the volcanic center Prometheus, are characterized by long-lived steady eruptions producing a compound flow field emplaced in an insulating manner over a period of years to decades. In contrast, "Pillanian" eruptions are characterized by large pyroclastic deposits and short-lived but high effusion rate eruptions from fissures feeding open-channel or open-sheet flows. Both types of eruptions commonly have ???100-km-tall, bright, SO2-rich plumes forming near the flow fronts and smaller deposits of red material that mark the vent for the silicate lavas. Copyright 2001 by the American Geophysical Union.

  14. Active Sites Environmental Monitoring Program: Mid-FY 1991 report

    Energy Technology Data Exchange (ETDEWEB)

    Ashwood, T.L.; Wickliff, D.S.; Morrissey, C.M.

    1991-10-01

    This report summarizes the activities of the Active Sites Environmental Monitoring Program (ASEMP) from October 1990 through March 1991. The ASEMP was established in 1989 by Solid Waste Operations and the Environmental Sciences Division to provide early detection and performance monitoring at active low-level radioactive waste (LLW) disposal sites in Solid Waste Storage Area (SWSA) 6 and transuranic (TRU) waste storage sites in SWSA 5 as required by chapters II and III of US Department of Energy Order 5820.2A. Monitoring results continue to demonstrate the no LLW is being leached from the storage vaults on the tumulus pads. Loading of vaults on Tumulus II began during this reporting period and 115 vaults had been loaded by the end of March 1991.

  15. 火山温室气体释放通量与观测的研究进展%Research Advances in Greenhouse Gases Degassing from Cenozoic Volcanic Active Fields

    Institute of Scientific and Technical Information of China (English)

    郭正府; 张茂亮; 孙玉涛; 成智慧; 张丽红; 刘嘉麒

    2015-01-01

    火山活动是地球深部碳循环的重要环节,火山区不仅在火山喷发期能够释放温室气体,而且在休眠期也能向大气圈中释放大量的温室气体。在当前全球温室气体减排的背景下,定量化地研究火山区对大气圈温室气体含量增加的贡献,对于识别自然因素和人类因素碳排放的相对规模、为国际碳排放谈判积累基础数据等均具有至关重要的科学价值和现实意义。本文对火山区温室气体的排放方式与特征、温室气体释放通量与成因的研究方法进行了简要概括,并综述了中国新生代典型火山区温室气体释放通量与成因的研究成果。结合国外温室气体排放研究现状,指出深入研究活火山(包括休眠火山)区的温室气体释放通量与成因对于估算火山来源温室气体的释放规模、建立火山未来喷发预测-预警体系、深入理解岩浆脱气过程与机制等问题均具有至关重要的现实意义和科学价值。%Volcanic activities are of great importance to the global deep carbon cycle,which could release large amount of greenhouse gases during both eruptive and quiescent stages,resulting in climatic and environmental changes on local and even global scales.Under the context of global warming,quantitative studies on the contribution of volcanic activities to rising of atmospheric greenhouse gases concentration are critical to discriminating carbon emissions associated with nature and human and to accumulating essential data for geological carbon budget.In this study,we briefly reviewed types,char-acteristics and research methods of greenhouse gases emissions,and the current status of research on fluxes and origin of greenhouse gases emitting from volcanic fields of China.Based on internationally accepted theory in volcanic-related green-house gases,we proposed that,systematic studies on fluxes and origin of greenhouse gases emitting from volcanic activities

  16. Survey and assessment of post volcanic activities of a young caldera lake, Lake Cuicocha, Ecuador

    Directory of Open Access Journals (Sweden)

    G. Gunkel

    2009-05-01

    Full Text Available Cuicocha is a young volcano adjacent to the inactive Pleistocene Cotacachi volcano complex, located in the western cordilleras of the Ecuadorian Andes. A series of eruptions with intensive ash emission and collapse of the caldera occurred around 4500–3000 y BP. A crater 3.2 km in diameter and a maximum depth of 450 m was formed. Further eruptions of the volcano occurred 1300 y BP and formed four smaller domes within the caldera. Over the last few hundred years, a caldera lake has developed, with a maximum depth of 148 m. The lake water is characterized by sodium carbonate with elevated concentrations of manganese, calcium and chloride. Nowadays, an emission of gases, mainly CO2, and an input of warm spring water occur in Lake Cuicocha. The zone of high activity is in the western basin of the lake at a depth of 78 m, and continuous gas emissions with sediment resuspension were observed using sonar. In the hypolimnion of the lake, CO2 accumulation occurs up to 0.2% saturation, but the risk of a limnic eruption can be excluded at present. The lake possesses monomictic stratification behaviour, and during overturn an intensive gas exchange with the atmosphere occurs. Investigations concerning the sedimentation processes of the lake suggest only a thin sediment layer of up to 10–20 cm in the deeper lake basin; in the western bay, in the area of gas emissions, the lake bottom is partly depleted of sediment in the form of holes, and no lake colmation exists. Decreases in the lake water level of about 30 cm y−1 indicate a percolation of water into fractures and fissures of the volcano, triggered by a nearby earthquake in 1987.

  17. Virunga Volcanoes Supersite: a collaborative initiative to improve Geohazards Assessment and Monitoring of Active Volcanoes in a highly populated region

    Science.gov (United States)

    Balagizi, Charles M.; Mahinda, Celestin K.; Yalire, Mathieu M.; Ciraba, Honoré M.; Mavonga, Georges T.

    2017-04-01

    Located within the western branch of the East African Rift System (EARS), the Virunga Volcanic Province is a young highly volcanically and seismically active region. It provides a unique opportunity to study deep mantle upwelling through the crust. Several Geohazards are encountered in this highly populated region, and include volcanic hazards (lava flows, volcanic gases and ash, …), earthquake hazard; landslide, mud flows and floods hazards. In addition, the overturn of Lake Kivu (which lies in the Kivu Graben, western branch of the EARS) could release huge CO2 and CH4 into the atmosphere. A few days after the January 17, 2002 Nyiragongo eruption whose lava flows devastated Goma city, destroying the houses of ˜120,000 people, forced a mass self-evacuation of ˜300,000 people of Goma (of estimated ˜400,000 inhabitants), and killed ˜140 people; the international scientific community deployed a "dream scientific team" to evaluate the state of Geohazards in the Virunga region. Particularly, the team had to check whether the stability of Lake Kivu that dissolves ˜300 and ˜60 km3 of CO2 and CH4 (at 0˚ C and 1 atm.) in its deep water was not disturbed due to Nyiragongo lava that entered the lake. Since 2002 several projects were funded with the main goal of accompanying the local scientific team to set up a more professional team to assess and continuous monitor Geohazards in the Virunga. For the time being, while Nyiragongo volcano solely threatens ˜1.5 million inhabitants of Goma (DR Congo) and Gisenyi (Rwanda) cities in addition to people living in the surrounding villages, and Lake Kivu threatening ˜3 million inhabitants of its catchment, the local scientists remain less qualified and equipped. Here we show that collaboration between Virunga local scientists and international scientists through the Geohazards Supersites network could be a most efficient pathway to improve Geohazards assessment and monitoring in the Virunga, and hence yield Disaster Risk

  18. Detection and Classification of Volcanic Earthquakes/Tremors in Central Anatolian Volcanic Province

    Science.gov (United States)

    Kahraman, Metin; Arda Özacar, A.; Bülent Tank, S.; Uslular, Göksu; Kuşcu, Gonca; Türkelli, Niyazi

    2017-04-01

    Central Anatolia has been characterized by active volcanism since 10 Ma which created the so called Central Anatolia Volcanic Province (CAVP) where a series of volcanoes are located along the NE-SW trend. The petrological investigations reveal that the magma source in the CAVP has both subduction and asthenospheric signature possibly due to tearing of ongoing northward subduction of African plate along Aegean and Cyprus arcs. Recently, a temporary seismic array was deployed within the scope of Continental Dynamics: Central Anatolian Tectonics (CD-CAT) project and provided a unique opportunity to study the deep seismic signature of the CAVP. Passive seismic imaging efforts and magnetotellurics (MT) observations revealed low velocity and high conductivity zones supporting the presence of localized partial melt bodies beneath the CAVP at varying depths, especially around Mt. Hasan which exhibits both geological and archeological evidences for its eruption around 7500 B.C. In Central Anatolia, local seismicity detected by the CD-CAT array coincides well with the active faults zones. However, active or potentially active volcanoes within CAVP are characterized by the lack of seismic activity. In this study, seismic data recorded by permanent stations of Regional Earthquake-Tsunami Monitoring Center were combined with temporary seismic data collected by the CD-CAT array to improve sampling density across the CAVP. Later, the continuous seismic waveforms of randomly selected time intervals were manually analyzed to identify initially undetected seismic sources which have signal characters matching to volcanic earthquakes/tremors. For candidate events, frequency spectrums are constructed to classify the sources according to their physical mechanisms. Preliminary results support the presence of both volcano-tectonic (VT) and low-period (LT) events within the CAVP. In the next stage, the spectral and polarization analyses techniques will be utilized to the entire seismic

  19. Geomorphic signatures of glacial activity in the Alba Patera volcanic province: Implications for recent frost accumulation on Mars

    Science.gov (United States)

    Sinha, Rishitosh K.; Murty, Sripada V. S.

    2013-08-01

    landforms lying within impact craters on Mars have led to the identification of two mechanisms for their formation: (1) intermittent deposition of atmospherically emplaced snow/ice during past spin-axis/orbital conditions and (2) flow of debris-covered ice-rich deposits. The maximum presence of the young ice/snow-rich features (thermal contraction crack polygons, gullies, arcuate ridges, and lobate debris tongues) was observed on the pole-facing slope, indicating that this slope was the preferred site for ice/snow accumulation (during the last 10 Ma). In this study, we investigated 30 craters lying in the Alba Patera volcanic province in the latitudinal bands between 45°N and 32.4°N. Morphological comparison of the younger ice/snow-rich features in these craters led us to conclude that glacial/periglacial features in Alba Patera are mainly present within pole-facing slopes of craters lying within 45°N-39°N. The craters lying within 40.2°N-40°N did not show any glacial/periglacial features. We suggest that the formation of these young ice/snow-rich features follows the same orientation trends as those of other older (>10 Ma) glacial features (debris-covered ice/snow-rich large deposits at the base of the crater wall) in the region. The present work has revealed that the onset of physical processes that result in the formation of glacial/periglacial landforms is also dependent on the changes in elevation ranges of the investigated craters in Alba Patera. Our results confirm past inferences for accumulation of ice/snow on Mars and suggest that the period of ice/snow accumulation activity in Alba Patera occurred throughout the Amazonian and lasted until the recent past, i.e., 2.1-0.4 Ma.

  20. Laboratory simulations of volcanic ash charging and conditions for volcanic lightning on Venus

    Science.gov (United States)

    Airey, Martin; Warriner-Bacon, Elliot; Aplin, Karen

    2017-04-01

    Lightning may be important in the emergence of life on Earth and elsewhere, as significant chemical reactions occur in the superheated region around the lightning channel. This, combined with the availability of phosphates in volcanic clouds, suggests that volcanic lightning could have been the catalyst for the formation of biological compounds on the early Earth [1]. In addition to meteorological lightning, volcanic activity also generates electrical discharges within charged ash plumes, which can be a significant contributor to atmospheric electricity on geologically active planets. The physical properties of other planetary atmospheres, such as that of Venus, have an effect on the processes that lead to the generation of volcanic lightning. Volcanism is known to have occurred on Venus in the past, and recent observations made by ESA's Venus Express satellite have provided evidence for currently active volcanism [2-4], and lightning discharges [e.g. 5]. Venusian lightning could potentially be volcanic in origin, since no meteorological mechanisms are known to separate charge effectively in its clouds [6]. The hunt for further evidence for lightning at Venus is ongoing, for example by means of the Lightning and Airglow Camera (LAC) [7] on Akatsuki, the current JAXA mission at Venus. Our laboratory experiments simulate ash generation and measure electrical charging of the ash under typical atmospheric conditions on Earth and Venus. The study uses a 1 litre chamber, which, when pressurised and heated, can simulate the high-pressure, high-temperature, carbon dioxide-dominated atmosphere of Venus at 10 km altitude ( 5 MPa, 650 K). A key finding of previous work [8] is that ash plume-forming eruptions are more likely to occur at higher altitudes such as these on Venus. The chamber contains temperature/pressure monitoring and logging equipment, a rock collision apparatus (based on [9]) to generate the charged rock fragments, and charge measurement electrodes connected

  1. Automatic landslides detection on Stromboli volcanic Island

    Science.gov (United States)

    Silengo, Maria Cristina; Delle Donne, Dario; Ulivieri, Giacomo; Cigolini, Corrado; Ripepe, Maurizio

    2016-04-01

    Landslides occurring in active volcanic islands play a key role in triggering tsunami and other related risks. Therefore, it becomes vital for a correct and prompt risk assessment to monitor landslides activity and to have an automatic system for a robust early-warning. We then developed a system based on a multi-frequency analysis of seismic signals for automatic landslides detection occurring at Stromboli volcano. We used a network of 4 seismic 3 components stations located along the unstable flank of the Sciara del Fuoco. Our method is able to recognize and separate the different sources of seismic signals related to volcanic and tectonic activity (e.g. tremor, explosions, earthquake) from landslides. This is done using a multi-frequency analysis combined with a waveform patter recognition. We applied the method to one year of seismic activity of Stromboli volcano centered during the last 2007 effusive eruption. This eruption was characterized by a pre-eruptive landslide activity reflecting the slow deformation of the volcano edifice. The algorithm is at the moment running off-line but has proved to be robust and efficient in picking automatically landslide. The method provides also real-time statistics on the landslide occurrence, which could be used as a proxy for the volcano deformation during the pre-eruptive phases. This method is very promising since the number of false detections is quite small (landslide increases. The final aim will be to apply this method on-line and for a real-time automatic detection as an improving tool for early warnings of tsunami-genic landslide activity. We suggest that a similar approach could be also applied to other unstable non-volcanic also slopes.

  2. When the hazard you're monitoring is the least of your troubles… the early days of a ubiquitous computing citizen science initiative on active volcanoes

    Science.gov (United States)

    van Manen, S. M.; Richards, M.; Seaton, R.; Cameron, I.; Avard, G.; Martinez, M.

    2014-12-01

    Approximately 500 million people live in close proximity to one or more of the world's 1500 active volcanoes, and this number is set to increase through population growth. The corresponding human, social, environmental and economic costs of volcanic activity are likewise set to rise. Monitoring of active volcanoes is imperative to minimize the impact of volcanic activity. However, people's responses towards risk are not just determined by objective scientific information, but also by socio-cognitive factors such as hazard salience; risk perception; anxiety levels and sense of self efficacy. This project aims to take a citizen science approach to the monitoring of hazardous volcanic gases: a low-cost automated ubiquitous technology station will increase spatial and temporal data resolution while providing citizens access to relevant, accurate, timely and local information. This means a single data stream can be used to develop a better understanding of volcanic degassing and raise levels of hazard salience and increase feelings of self efficacy. A year and two prototypes into the project, this work presents the lessons learnt to date. Careful consideration was given to the station design in light of the harsh conditions it may encounter. Once the first prototypes were built, results from the initial lab tests were encouraging. Yet it wasn't until the stations were taken into the field that unexpected challenges were encountered: humans. During the very first field trial the prototype was vandalised, our second attempt was thwarted by customs and courier services. As a result, we've had to be flexible in our approach and adapt our strategy and station design in response to these events, which will eventually result in a better outcome. However, this case study serves as a reminder of the importance of considering factors beyond the equipment, data, interpretation and involvement of the public, when planning and implementing a citizen science initiative.

  3. Slope instability induced by volcano-tectonics as an additional source of hazard in active volcanic areas: the case of Ischia island (Italy)

    Science.gov (United States)

    Della Seta, Marta; Marotta, Enrica; Orsi, Giovanni; de Vita, Sandro; Sansivero, Fabio; Fredi, Paola

    2012-01-01

    Ischia is an active volcanic island in the Gulf of Naples whose history has been dominated by a caldera-forming eruption (ca. 55 ka) and resurgence phenomena that have affected the caldera floor and generated a net uplift of about 900 m since 33 ka. The results of new geomorphological, stratigraphical and textural investigations of the products of gravitational movements triggered by volcano-tectonic events have been combined with the information arising from a reinterpretation of historical chronicles on natural phenomena such as earthquakes, ground deformation, gravitational movements and volcanic eruptions. The combined interpretation of all these data shows that gravitational movements, coeval to volcanic activity and uplift events related to the long-lasting resurgence, have affected the highly fractured marginal portions of the most uplifted Mt. Epomeo blocks. Such movements, mostly occurring since 3 ka, include debris avalanches; large debris flows (lahars); smaller mass movements (rock falls, slumps, debris and rock slides, and small debris flows); and deep-seated gravitational slope deformation. The occurrence of submarine deposits linked with subaerial deposits of the most voluminous mass movements clearly shows that the debris avalanches impacted on the sea. The obtained results corroborate the hypothesis that the behaviour of the Ischia volcano is based on an intimate interplay among magmatism, resurgence dynamics, fault generation, seismicity, slope oversteepening and instability, and eruptions. They also highlight that volcano-tectonically triggered mass movements are a potentially hazardous phenomena that have to be taken into account in any attempt to assess volcanic and related hazards at Ischia. Furthermore, the largest mass movements could also flow into the sea, generating tsunami waves that could impact on the island's coast as well as on the neighbouring and densely inhabited coast of the Neapolitan area.

  4. Submarine volcanoes along the Aegean volcanic arc

    Science.gov (United States)

    Nomikou, Paraskevi; Papanikolaou, Dimitrios; Alexandri, Matina; Sakellariou, Dimitris; Rousakis, Grigoris

    2013-06-01

    The Aegean volcanic arc has been investigated along its offshore areas and several submarine volcanic outcrops have been discovered in the last 25 years of research. The basic data including swath bathymetric maps, air-gun profiles, underwater photos and samples analysis have been presented along the four main volcanic groups of the arc. The description concerns: (i) Paphsanias submarine volcano in the Methana group, (ii) three volcanic domes to the east of Antimilos Volcano and hydrothermal activity in southeast Milos in the Milos group, (iii) three volcanic domes east of Christiana and a chain of about twenty volcanic domes and craters in the Kolumbo zone northeast of Santorini in the Santorini group and (iv) several volcanic domes and a volcanic caldera together with very deep slopes of several volcanic islands in the Nisyros group. The tectonic structure of the volcanic centers is described and related to the geometry of the arc and the neotectonic graben structures that usually host them. The NE-SW direction is dominant in the Santorini and Nisyros volcanic groups, located at the eastern part of the arc, where strike-slip is also present, whereas NW-SE direction dominates in Milos and Methana at the western part, where co-existence of E-W disrupting normal faults is observed. The volcanic relief reaches 1100-1200 m in most cases. This is produced from the outcrops of the volcanic centers emerging usually at 400-600 m depth and ending either below sea level or at high altitudes of 600-700 m on the islands. Hydrothermal activity at relatively high temperatures observed in Kolumbo is remarkable whereas low temperature phenomena have been detected in the Santorini caldera around Kameni islands and in the area southeast of Milos. In Methana and Nisyros, hydrothermal activity seems to be limited in the coastal areas without other offshore manifestations.

  5. Continuous gravity monitoring of geothermal activity; Renzoku juryoku sokutei ni yoru chinetsu katsudo no monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Sugihara, M. [Geological Survey of Japan, Tsukuba (Japan)

    1997-05-27

    To clarify the geothermal activity in the geothermal fields in New Zealand, gravity monitoring was conducted using SCINTREX automatic gravimeter. The measurements were conducted between the end of January and the beginning of March, 1996. Firstly, continuous monitoring was conducted at the standard point for about ten days, and the tidal components were estimated from the records. After that, continuous monitoring was conducted at Waimangu area for several days. Continuous monitoring was repeated at the standard point, again. At the Waimangu area, three times of changes in the pulse-shape amplitude of 0.01 mgal having a width of several hours were observed. For the SCINTREX gravimeter, the inclination of gravimeter is also recorded in addition to the change of gravity. During the monitoring, the gravimeter was also inclined with the changes of gravity. This inclination was useful not only for the correction of gravity measured, but also for evaluating the ground fluctuation due to the underground pressure source. It is likely that the continuous gravity monitoring is the relatively conventional technique which is effective for prospecting the change of geothermal reservoir. 2 figs.

  6. GIS-Based emergency and evacuation planning for volcanic hazards in New Zealand

    DEFF Research Database (Denmark)

    Cole, J. W.; Sabel, C. E.; Blumenthal, E.

    2005-01-01

    in New Zealand is high, with 10 volcanoes or volcanic centres (Auckland, Bay of Islands, Haroharo, Mayor Island, Ruapehu, Taranaki, Tarawera, Taupo, Tongariro (including Ngauruhoe) and White Island) recognised as active or potentially active. In addition there are many active and potentially active...... (reduction, readiness, response and recovery) can benefit from CIS, including applications related to transportation systems, a critical element in managing effective lifelines in an emergency. This is particularly true immediately before and during a volcanic eruption. The potential for volcanic activity...... volcanoes along the Kermadec Island chain. There is a great deal of background information on all of these volcanoes, and GIS is currently being used for some aspects of monitoring (e.g. ERS and Envisat radar interferometry for observing deformation prior to eruptions). If an eruption is considered imminent...

  7. Multidisciplinary exploratory study of a geothermal resource in the active volcanic arc of Basse-Terre (Guadeloupe, Lesser Antilles)

    Science.gov (United States)

    Navelot, Vivien; Favier, Alexiane; Géraud, Yves; Diraison, Marc; Corsini, Michel; Verati, Chrystèle; Lardeaux, Jean-Marc; Mercier de Lépinay, Jeanne; Munschy, Marc

    2017-04-01

    The GEOTREF project (high enthalpy geothermal energy in fractured reservoirs), supported by the French government program, "Investissements d'avenir" develops a sustainable geothermal resource in the Vieux Habitants area, 8-km south of the currently exploited Bouillante geothermal field. The Basse Terre Island is a recent volcanic arc (geothermal gradient of 70 ˚ C/km.

  8. Embedded Triboelectric Active Sensors for Real-Time Pneumatic Monitoring.

    Science.gov (United States)

    Fu, Xian Peng; Bu, Tian Zhao; Xi, Feng Ben; Cheng, Ting Hai; Zhang, Chi; Wang, Zhong Lin

    2017-09-20

    Pneumatic monitoring sensors have great demands for power supply in cylinder systems. Here, we present an embedded sliding triboelectric nanogenerator (TENG) in air cylinder as active sensors for position and velocity monitoring. The embedded TENG is composed of a circular poly(tetrafluoroethylene) polymer and a triangular copper electrode. The working mechanism as triboelectric active sensors and electric output performance are systematically investigated. By integrating into the pneumatic system, the embedded triboelectric active sensors have been used for real-time air pressure/flow monitoring and energy storage. Air pressures are measured from 0.04 to 0.12 MPa at a step of 0.02 MPa with a sensitivity of 49.235 V/MPa, as well as airflow from 50 to 250 L/min at a step of 50 L/min with a sensitivity of 0.002 μA·min/L. This work has first demonstrated triboelectric active sensors for pneumatic monitoring and may promote the development of TENG in intelligent pneumatic system.

  9. Applied research of environmental monitoring using instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Young Sam; Moon, Jong Hwa; Chung, Young Ju

    1997-08-01

    This technical report is written as a guide book for applied research of environmental monitoring using Instrumental Neutron Activation Analysis. The contents are as followings; sampling and sample preparation as a airborne particulate matter, analytical methodologies, data evaluation and interpretation, basic statistical methods of data analysis applied in environmental pollution studies. (author). 23 refs., 7 tabs., 9 figs.

  10. Leisure Time Activities, Parental Monitoring and Drunkenness in Adolescents

    NARCIS (Netherlands)

    Tomcikova, Zuzana; Veselska, Zuzana; Geckova, Andrea Madarasova; van Dijk, Jitse P.; Reijneveld, Sijmen A.

    2013-01-01

    Background: The aim of this cross-sectional study was to explore the association between adolescent drunkenness and participation in risky leisure time activities and parental monitoring. Methods: A sample of 3,694 Slovak elementary school students (mean age 14.5 years; 49.0% males) was assessed for

  11. Leisure time activities, parental monitoring and drunkenness in adolescents

    NARCIS (Netherlands)

    Tomcikova, Z.; Veselska, Z.; Madarasova Geckova, A.; van Dijk, J.P.; Reijneveld, S.A.

    2012-01-01

    Background: The aim of this cross-sectional study was to explore the association between adolescent drunkenness and participation in risky leisure time activities and parental monitoring. Methods: A sample of 3,694 Slovak elementary school students (mean age 14.5 years; 49.0% males) was assessed for

  12. Electrical Resistivity Monitoring of an Active Hydrothermal Degassing Area at Solfatara, Phlegrean Fields.

    Science.gov (United States)

    Vandemeulebrouck, J.; Byrdina, S.; Grangeon, J.; Lebourg, T.; Bascou, P.; Mangiacapra, A.

    2015-12-01

    Campi Flegrei caldera (CFc) is an active volcanic complex covering a ~100 km² densely populated area in the western part of Naples (Italy) that is presently showing clear signs of unrest. Solfatara volcano, a tuff cone crater formed ~4000 yrs B.P. ago by phreato-magmatic eruptions represents the main degassing outflow of CFc. Magmatic gases which are exsolved from a ~8 km deep magmatic reservoir mix at 4 km depth with meteoric hydrothermal fluids then reach the surface in the Solfatara area. These hydrothermal and magmatic gases, mainly H2O and CO2, are released through both diffuse degassing structures and fumaroles. In the frame of the MedSuv (Mediterranean Supervolcanoes) FP7 european project , we are performing a time-lapse electrical resistivity monitoring of an active degassing area of Solfatara. Using a 500-m-long cable and 48 electrodes, an electrical resistivity tomography (ERT) is performed on a two-day basis since May 2013. The time-lapse inversion of the ERT gives an image of the temporal variations of resistivity up to 100 m depth that can be compared with the variations of ground deformation, CO2 flux, soil temperature and seismic ambient noise. Resistivity variations can originate from fluid composition, gas ratio and temperature. For example, the abrupt change of resistivity that was observed mid-2014 during a period of uplift and gas flux increase, could be associated with the rise of hydrothermal fluids.

  13. Ambient Noise Surface Wave Tomography of the volcanic systems of eastern Iceland

    Science.gov (United States)

    Green, R. G.; Priestley, K. F.; White, R. S.

    2015-12-01

    The Vatnajökull region of central-east Iceland lies above the head of the Iceland mantle plume where the crust is thickest due to enhanced melt supply. As a result the region contains a high density of volcanic rift systems, with six large subglacial central volcanoes. Due to the ice cover, the geological structure of the area and the location of past eruptions are poorly known. Imaging of the crustal velocity heterogeneities beneath the ice sheet aims to reveal much in terms of the structure of these volcanic plumbing systems. Mapping of significant velocity changes through time may also be indicative of movement of melt around the central volcanoes; one of which (Bárðarbunga) experienced a major rifting event in August 2014 (Sigmundsson et al. Nature 2015, Green et al. Nature Geosci. 2015). We present results from tomographic imaging of the volcanic systems in the region, using continuous data from a local broadband seismic network in central-east Iceland which provides excellent ray path coverage of the volcanic systems. This is supplemented by data from the HOTSPOT and ICEMELT experiments and the permanent monitoring stations of the Icelandic Meteorological Office. We process the continuous data following Benson et al. 2007 and automatic frequency-time analysis (FTAN) routines are used to extract more than 9000 dispersion measurements. We then generate Rayleigh wave group velocity maps which we present here. We find low velocity regions beneath the Vatnajökull icecap which are bounded by the surface expression of the volcanic rift systems. The lower velocities also extend north-west to the volcanic system under the Hofsjökull ice cap, and northwards towards Askja and the volcanic systems of the northern volcanic zone. We also produce locations and focal mechanisms of earthquakes caused by magmatic and hydrothermal activity to correlate structure with the activity of the volcanic systems.

  14. Influence of volcanic activity and anthropic impact in the trace element contents of fishes from the North Patagonia in a global context.

    Science.gov (United States)

    Bubach, D F; Macchi, P J; Pérez Catán, S

    2015-11-01

    The elemental contents in salmonid muscle and liver tissues from different lakes around the world were investigated. Fish from pristine areas were compared with those fishes from impacted environments, both by volcanic and anthropogenic activities. Within the data, special attention was given to fishes from the Andean Patagonian lakes in two contexts: local and global. The local evaluation includes geological and limnological parameters and diet composition which were obtained through a data search from published works. The volcanic influence in Andean Patagonian lakes was mainly observed by an increase of cesium (Cs) and rubidium (Rb) concentrations in fishes, influenced by calcium (Ca) and potassium (K) water contents. Zinc (Zn), selenium (Se), iron (Fe), silver (Ag), and mercury (Hg) contents in fishes showed the effect of the geological substratum, and some limnological parameters. The diet composition was another factor which affects the elemental concentration in fishes. The analyzed data showed that the fishes from Andean Patagonian lakes had elemental content patterns corresponding to those of pristine regions with volcanic influence. Selenium and Ag contents from Andean Patagonian fishes were the highest reported.

  15. Monitoring of fumarole discharge and CO2 soil degassing in the Azores: contribution to volcanic surveillance and public health risk assessment

    Directory of Open Access Journals (Sweden)

    C. Faria

    2005-06-01

    Full Text Available Fluid geochemistry monitoring in the Azores involves the regular sampling and analysis of gas discharges from fumaroles and measurements of CO2 diffuse soil gas emissions. Main degassing areas under monitoring are associated with hydrothermal systems of active central volcanoes in S. Miguel, Terceira and Graciosa islands. Fumarole discharge analysis since 1991 show that apart from steam these gas emissions are CO2 dominated with H2S, H2, CH4 and N2 in minor amounts. Mapping of CO2 diffuse soil emissions in S. Miguel Island lead to the conclusion that some inhabited areas are located within hazard-zones. At Furnas village, inside Furnas volcano caldera, about 62% of the 896 houses are within the CO2 anomaly, 5% being in areas of moderate to high risk. At Ribeira Seca, on the north flank of Fogo volcano, few family houses were evacuated when CO2 concentrations in the air reached 8 mol%. To assess and analyse the CO2 soil flux emissions, continuous monitoring stations were installed in S. Miguel (2, Terceira and Graciosa islands. The statistical analysis of the data showed that some meteorological parameters influence the CO2 flux. The average of CO2 flux in S. Miguel stations ranges from 250 g/m2/d at Furnas volcano to 530 g/m2/d at Fogo volcano. At Terceira Island it is about 330 g/m2/d and at Graciosa 4400 g/m2/d.

  16. Eruption processes and deposit characteristics at the monogenetic Mt. Gambier Volcanic Complex, SE Australia: implications for alternating magmatic and phreatomagmatic activity

    Science.gov (United States)

    van Otterloo, Jozua; Cas, Raymond A. F.; Sheard, Malcolm J.

    2013-08-01

    The ˜5 ka Mt. Gambier Volcanic Complex in the Newer Volcanics Province, Australia is an extremely complex monogenetic, volcanic system that preserves at least 14 eruption points aligned along a fissure system. The complex stratigraphy can be subdivided into six main facies that record alternations between magmatic and phreatomagmatic eruption styles in a random manner. The facies are (1) coherent to vesicular fragmental alkali basalt (effusive/Hawaiian spatter and lava flows); (2) massive scoriaceous fine lapilli with coarse ash (Strombolian fallout); (3) bedded scoriaceous fine lapilli tuff (violent Strombolian fallout); (4) thin-medium bedded, undulating very fine lapilli in coarse ash (dry phreatomagmatic surge-modified fallout); (5) palagonite-altered, cross-bedded, medium lapilli to fine ash (wet phreatomagmatic base surges); and (6) massive, palagonite-altered, very poorly sorted tuff breccia and lapilli tuff (phreato-Vulcanian pyroclastic flows). Since most deposits are lithified, to quantify the grain size distributions (GSDs), image analysis was performed. The facies are distinct based on their GSDs and the fine ash to coarse+fine ash ratios. These provide insights into the fragmentation intensities and water-magma interaction efficiencies for each facies. The eruption chronology indicates a random spatial and temporal sequence of occurrence of eruption styles, except for a "magmatic horizon" of effusive activity occurring at both ends of the volcanic complex simultaneously. The eruption foci are located along NW-SE trending lineaments, indicating that the complex was fed by multiple dykes following the subsurface structures related to the Tartwaup Fault System. Possible factors causing vent migration along these dykes and changes in eruption styles include differences in magma ascent rates, viscosity, crystallinity, degassing and magma discharge rate, as well as hydrological parameters.

  17. Therapeutic Drug Monitoring in the Treatment of Active Tuberculosis

    Directory of Open Access Journals (Sweden)

    Aylin Babalik

    2011-01-01

    Full Text Available Therapeutic drug monitoring ensures optimal dosing while aiming to reduce toxicity. However, due to the high costs and complexity of testing, therapeutic drug monitoring is not routinely used in the treatment of individuals with active tuberculosis, despite the efficacy demonstrated in several randomized trials. This study reviewed data spanning five years regarding the frequency of finding low drug levels in patients with tuberculosis, the dosing adjustments that were required to achieve adequate levels and the factors associated with low drug levels.

  18. The Timber Mountain magmato-thermal event: An intense widespread culmination of magmatic and hydrothermal activity at the southwestern Nevada volcanic field

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, M.R. Jr.

    1988-05-01

    Eruption of the Rainier Mesa and Ammonia Tanks Members Timber Mountain Tuff at about 11.5 and 11.3 Ma, respectively, resulted in formation of the timber Mountain (TM) caldera; new K-Ar ages show that volcanism within and around the TM caldera continued for about 1 m.y. after collapse. Some TM age magmatic activity took place west and southeast of the TM caldera in the Beatty -- Bullfrog Hills and Shoshone Mountain areas, suggesting that volcanic activity at the TM caldera was an intense expression of an areally extensive magmatic system active from about 11.5 to 10Ma. Epithermal Au-Ag, Hg and fluorite mineralization and hydrothermal alteration are found in both within and surrounding the Timber Mountain -- Oasis Valley caldera complex. New K-Ar ages date this hydrothermal activity between about 13 and 10 Ma, largely between about 11.5 and 10 Ma, suggesting a genetic relation of hydrothermal activity to the TM magmatic system.

  19. Temporal variations in the constituents of volcanic ash and adherent water-soluble components in the Unzen Fugendake eruption during 1990-1991

    Science.gov (United States)

    Nogami, K.; Hirabayashi, J.; Ohba, T.; Ossaka, J.; Yamamoto, M.; Akagi, S.; Ozawa, T.; Yoshida, M.

    2001-07-01

    A change in the chemical compositions of volcanic gases is one of the noticeable phenomena that frequently occurs prior to an eruption. Analysis of the water-soluble components adhering to volcanic ash is available for remote monitoring of volcanic gases from inaccessible volcanoes. It is a secure method for monitoring volcanic activity without using particular devices. Prolonged volcanic eruption at the Unzen Fugendake volcano from 1990 to 1995 started with a phreatic eruption after 198 years of dormancy. Volcanic activity changed from a phreatic and phreatomagmatic eruption to a magmatic eruption with pyroclastic flows in May 1991. The relationship between the chemical composition of volcanic ash and the contents of the water-soluble components adhering to it are discussed in relation to the early stage of the long-term eruption. Volcanic ash ejected by phreatic and phreatomagmatic eruption before dome formation was the product of the alteration in the volcanoclastic materials beneath the surface. The ash had a high content of water-soluble components, which was caused by the absorption of hydrogen chloride and sulfur dioxide gases from magma into wet debris before dome formation. Volcanic ashes which were generated by pyroclastic flows after dome formation were fresh lava fragments. While the contents of water-soluble sulfate adhering to the ash noticeably decreased, those of water-soluble chloride adhering to the ash hardly decreased. The considerable decrease in the contents of water-soluble sulfate was caused by the reaction of volcanic gases with dry lava fragments. Contrary to this, the concentration of hydrogen chloride gas in ash clouds was extremely high, which obstructed the decrease in the water-soluble chloride content in the ash. Volatility of chlorine and sulfur from volcanic rock suggests that the inner temperature of pyroclastic flows was higher than 600~700° C at least.

  20. On-line Monitoring and Active Control for Transformer Noise

    Science.gov (United States)

    Liang, Jiabi; Zhao, Tong; Tian, Chun; Wang, Xia; He, Zhenhua; Duan, Lunfeng

    This paper introduces the system for on-line monitoring and active noise control towards the transformer noise based on LabVIEW and the hardware equipment including the hardware and software. For the hardware part, it is mainly focused on the composition and the role of hardware devices, as well as the mounting location in the active noise control experiment. And the software part introduces the software flow chats, the measurement and analysis module for the sound pressure level including A, B, C weighting methods, the 1/n octave spectrum and the power spectrum, active noise control module and noise data access module.

  1. Remote monitoring of biodynamic activity using electric potential sensors

    Energy Technology Data Exchange (ETDEWEB)

    Harl, C J; Prance, R J; Prance, H [Centre for Physical Electronics and Quantum Technology, Department of Engineering and Design, School of Science and Technology, University of Sussex, Brighton, BN1 9QT (United Kingdom)], E-mail: c.j.harland@sussex.ac.uk

    2008-12-01

    Previous work in applying the electric potential sensor to the monitoring of body electrophysiological signals has shown that it is now possible to monitor these signals without needing to make any electrical contact with the body. Conventional electrophysiology makes use of electrodes which are placed in direct electrical contact with the skin. The electric potential sensor requires no cutaneous electrical contact, it operates by sensing the displacement current using a capacitive coupling. When high resolution body electrophysiology is required a strong (capacitive) coupling is used to maximise the collected signal. However, in remote applications where there is typically an air-gap between the body and the sensor only a weak coupling can be achieved. In this paper we demonstrate that the electric potential sensor can be successfully used for the remote sensing and monitoring of bioelectric activity. We show examples of heart-rate measurements taken from a seated subject using sensors mounted in the chair. We also show that it is possible to monitor body movements on the opposite side of a wall to the sensor. These sensing techniques have biomedical applications for non-contact monitoring of electrophysiological conditions and can be applied to passive through-the-wall surveillance systems for security applications.

  2. Sentinel-1 Contribution to Monitoring Maritime Activity in the Arctic

    Science.gov (United States)

    Santamaria, Carlos; Greidanus, Harm; Fournier, Melanie; Eriksen, Torkild; Vespe, Michele; Alvarez, Marlene; Arguedas, Virginia Fernandez; Delaney, Conor; Argentieri, Pietro

    2016-08-01

    This paper presents results on the use of Sentinel-1 combined with satellite AIS to monitor maritime activity in the Arctic. Such activities are expected to increase, even if not uniformly across the Arctic, as the ice cover in the region retreats due to changes in climate. The objectives of monitoring efforts in the region can vary from country to country, but are generally related to increasing awareness on non- cooperative, small and cruise ships, fisheries, safety at sea, and Search and Rescue. A ship monitoring study has been conducted, involving more than 2,000 Sentinel-1 images acquired during one year in the central Arctic, where the ship densities are high. The main challenges to SAR-based monitoring in this area are described, solutions for some of them are proposed, and analyses of the results are shown. With the high detection thresholds needed to prevent false alarms from sea ice, 16% of the ships detected overall in the Sentinel-1 images have not been correlated to AIS- transmitting ships, and 48% of the AIS-transmitting ships are not correlated to ships detected in the images.

  3. Catastrophic volcanic collapse: relation to hydrothermal processes.

    Science.gov (United States)

    López, D L; Williams, S N

    1993-06-18

    Catastrophic volcanic collapse, without precursory magmatic activity, is characteristic of many volcanic disasters. The extent and locations of hydrothermal discharges at Nevado del Ruiz volcano, Colombia, suggest that at many volcanoes collapse may result from the interactions between hydrothermal fluids and the volcanic edifice. Rock dissolution and hydrothermal mineral alteration, combined with physical triggers such as earth-quakes, can produce volcanic collapse. Hot spring water compositions, residence times, and flow paths through faults were used to model potential collapse at Ruiz. Caldera dimensions, deposits, and alteration mineral volumes are consistent with parameters observed at other volcanoes.

  4. Statistical eruption forecast for the Chilean Southern Volcanic Zone: typical probabilities of volcanic eruptions as baseline for possibly enhanced activity following the large 2010 Concepción earthquake

    Directory of Open Access Journals (Sweden)

    Y. Dzierma

    2010-10-01

    Full Text Available A probabilistic eruption forecast is provided for ten volcanoes of the Chilean Southern Volcanic Zone (SVZ. Since 70% of the Chilean population lives in this area, the estimation of future eruption likelihood is an important part of hazard assessment. After investigating the completeness and stationarity of the historical eruption time series, the exponential, Weibull, and log-logistic distribution functions are fit to the repose time distributions for the individual volcanoes and the models are evaluated. This procedure has been implemented in two different ways to methodologically compare details in the fitting process. With regard to the probability of at least one VEI ≥ 2 eruption in the next decade, Llaima, Villarrica and Nevados de Chillán are most likely to erupt, while Osorno shows the lowest eruption probability among the volcanoes analysed. In addition to giving a compilation of the statistical eruption forecasts along the historically most active volcanoes of the SVZ, this paper aims to give "typical" eruption probabilities, which may in the future permit to distinguish possibly enhanced activity in the aftermath of the large 2010 Concepción earthquake.

  5. QA/QC activities and ecological monitoring in the Acid Deposition Monitoring Network in East Asia (EANET

    Directory of Open Access Journals (Sweden)

    Ueda H

    2009-01-01

    Full Text Available An overview is presented of Quality assurance/Quality control QA/QC activities and current features of the ecological monitoring in the frame of the Acid Deposition Monitoring Network in East Asia EANET. It is stressed that standardization of the methodologies applicable for new topics, such as the catchment analysis and ozone impacts, should be investigated for future monitoring.

  6. Volcanic hazard assessment for the Canary Islands (Spain) using extreme value theory, and the recent volcanic eruption of El Hierro

    Science.gov (United States)

    Sobradelo, R.; Martí, J.; Mendoza-Rosas, A. T.; Gómez, G.

    2012-04-01

    The Canary Islands are an active volcanic region densely populated and visited by several millions of tourists every year. Nearly twenty eruptions have been reported through written chronicles in the last 600 years, suggesting that the probability of a new eruption in the near future is far from zero. This shows the importance of assessing and monitoring the volcanic hazard of the region in order to reduce and manage its potential volcanic risk, and ultimately contribute to the design of appropriate preparedness plans. Hence, the probabilistic analysis of the volcanic eruption time series for the Canary Islands is an essential step for the assessment of volcanic hazard and risk in the area. Such a series describes complex processes involving different types of eruptions over different time scales. Here we propose a statistical method for calculating the probabilities of future eruptions which is most appropriate given the nature of the documented historical eruptive data. We first characterise the eruptions by their magnitudes, and then carry out a preliminary analysis of the data to establish the requirements for the statistical method. Past studies in eruptive time series used conventional statistics and treated the series as an homogeneous process. In this paper, we will use a method that accounts for the time-dependence of the series and includes rare or extreme events, in the form of few data of large eruptions, since these data require special methods of analysis. Hence, we will use a statistical method from extreme value theory. In particular, we will apply a non-homogeneous Poisson process to the historical eruptive data of the Canary Islands to estimate the probability of having at least one volcanic event of a magnitude greater than one in the upcoming years. Shortly after the publication of this method an eruption in the island of El Hierro took place for the first time in historical times, supporting our method and contributing towards the validation of

  7. Active Geophysical Monitoring in Oil and Gas Industry

    Science.gov (United States)

    Bakulin, A.; Calvert, R.

    2005-12-01

    Effective reservoir management is a Holy Grail of the oil and gas industry. Quest for new technologies is never ending but most often they increase effectiveness and decrease the costs. None of the newcomers proved to be a silver bullet in such a key metric of the industry as average oil recovery factor. This factor is still around 30 %, meaning that 70 % of hydrocarbon reserves are left in the ground in places where we already have expensive infrastructure (platforms, wells) to extract them. Main reason for this inefficiency is our inability to address realistic reservoir complexity. Most of the time we fail to properly characterize our reservoirs before production. As a matter of fact, one of the most important parameters -- permeability -- can not be mapped from remote geophysical methods. Therefore we always start production blind even though reservoir state before production is the simplest one. Once first oil is produced, we greatly complicate the things and quickly become unable to estimate the state and condition of the reservoir (fluid, pressures, faults etc) or oilfield hardware (wells, platforms, pumps) to make a sound next decision in the chain of reservoir management. Our modeling capabilities are such that if we know true state of the things - we can make incredibly accurate predictions and make extremely efficient decisions. Thus the bottleneck is our inability to properly describe the state of the reservoirs in real time. Industry is starting to recognize active monitoring as an answer to this critical issue. We will highlight industry strides in active geophysical monitoring from well to reservoir scale. It is worth noting that when one says ``monitoring" production technologists think of measuring pressures at the wellhead or at the pump, reservoir engineers think of measuring extracted volumes and pressures, while geophysicist may think of change in elastic properties. We prefer to think of monitoring as to measuring those parameters of the

  8. Integrated active sensor system for real time vibration monitoring.

    Science.gov (United States)

    Liang, Qijie; Yan, Xiaoqin; Liao, Xinqin; Cao, Shiyao; Lu, Shengnan; Zheng, Xin; Zhang, Yue

    2015-11-05

    We report a self-powered, lightweight and cost-effective active sensor system for vibration monitoring with multiplexed operation based on contact electrification between sensor and detected objects. The as-fabricated sensor matrix is capable of monitoring and mapping the vibration state of large amounts of units. The monitoring contents include: on-off state, vibration frequency and vibration amplitude of each unit. The active sensor system delivers a detection range of 0-60 Hz, high accuracy (relative error below 0.42%), long-term stability (10000 cycles). On the time dimension, the sensor can provide the vibration process memory by recording the outputs of the sensor system in an extend period of time. Besides, the developed sensor system can realize detection under contact mode and non-contact mode. Its high performance is not sensitive to the shape or the conductivity of the detected object. With these features, the active sensor system has great potential in automatic control, remote operation, surveillance and security systems.

  9. Global scale concentrations of volcanic activity on Venus: A summary of three 23rd Lunar and Planetary Science Conference abstracts. 1: Venus volcanism: Global distribution and classification from Magellan data. 2: A major global-scale concentration of volcanic activity in the Beta-Atla-Themis region of Venus. 3: Two global concentrations of volcanism on Venus: Geologic associations and implications for global pattern of upwelling and downwelling

    Science.gov (United States)

    Crumpler, L. S.; Aubele, Jayne C.; Head, James W.; Guest, J.; Saunders, R. S.

    1992-01-01

    As part of the analysis of data from the Magellan Mission, we have compiled a global survey of the location, dimensions, and subsidiary notes of all identified volcanic features on Venus. More than 90 percent of the surface area was examined and the final catalog comprehensively identifies 1548 individual volcanic features larger than approximately 20 km in diameter. Volcanic features included are large volcanoes, intermediate volcanoes, fields of small shield volcanoes, calderas, large lava channels, and lava floods as well as unusual features first noted on Venus such as coronae, arachnoids, and novae.

  10. 40Ar/39Ar dating of tuff vents in the Campi Flegrei caldera (southern Italy): Toward a new chronostratigraphic reconstruction of the Holocene volcanic activity

    Science.gov (United States)

    Fedele, L.; Insinga, D.D.; Calvert, A.T.; Morra, V.; Perrotta, A.; Scarpati, C.

    2011-01-01

    The Campi Flegrei hosts numerous monogenetic vents inferred to be younger than the 15 ka Neapolitan Yellow Tuff. Sanidine crystals from the three young Campi Flegrei vents of Fondi di Baia, Bacoli and Nisida were dated using 40Ar/39Ar geochronology. These vents, together with several other young edifices, occur roughly along the inner border of the Campi Flegrei caldera, suggesting that the volcanic conduits are controlled by caldera-bounding faults. Plateau ages of ∼9.6 ka (Fondi di Baia), ∼8.6 ka (Bacoli) and ∼3.9 ka (Nisida) indicate eruptive activity during intervals previously interpreted as quiescent. A critical revision, involving calendar age correction of literature 14C data and available 40Ar/39Ar age data, is presented. A new reference chronostratigraphic framework for Holocene Phlegrean activity, which significantly differs from the previously adopted ones, is proposed. This has important implications for understanding the Campi Flegrei eruptive history and, ultimately, for the evaluation of related volcanic risk and hazard, for which the inferred history of its recent activity is generally taken into account.

  11. Human psychophysiological activity monitoring methods using fiber optic sensors

    Science.gov (United States)

    Zyczkowski, M.; Uzieblo-Zyczkowska, B.

    2010-10-01

    The paper presents the concept of fiber optic sensor system for human psycho-physical activity detection. A fiber optic sensor that utilizes optical phase interferometry or intensity in modalmetric to monitor a patient's vital signs such as respiration cardiac activity, blood pressure and body's physical movements. The sensor, which is non-invasive, comprises an optical fiber interferometer that includes an optical fiber proximately situated to the patient so that time varying acusto-mechanical signals from the patient are coupled into the optical fiber. The system can be implemented in embodiments ranging form a low cost in-home to a high end product for in hospital use.

  12. Limited Activity Monitoring in Toddlers with Autism Spectrum Disorder

    OpenAIRE

    Shic, Frederick; Bradshaw, Jessica; Klin, Ami; Scassellati, Brian; Chawarska, Katarzyna

    2010-01-01

    This study used eye-tracking to examine how 20-month old toddlers with autism spectrum disorder (ASD) (N=28), typical development (TD) (N=34), and non-autistic developmental delays (DD) (N=16) monitored the activities occurring in a context of an adult-child play interaction. Toddlers with ASD, in comparison to control groups, showed less attention to the activities of others and focused more on background objects (e.g. toys). In addition, while all groups spent the same time overall looking ...

  13. Experimental studies of anomalous radon activity in the Tlamacas Mountain, Popocatepetl Volcano area, México: new tools to study lithosphere-atmosphere coupling for forecasting volcanic and seismic events

    Directory of Open Access Journals (Sweden)

    Jose Antonio Lopez Cruz Abeyro

    2012-04-01

    Full Text Available

    This study presents and discusses the results of soil radon monitoring at three different volcano sites and one reference site, from December 2007 to January 2009. This relates to the activity of the Popocatepetl Volcano and a radon survey and gamma-ray spectrometry in the area between Paso de Cortes and Tlamacas Mountain, and in the adjacent regions. The results are applied to the aspects of atmosphere electricity and lithosphere-atmosphere coupling in relation to the forecasting of volcano and earthquake activity. The monitoring of radon release reveals a decrease in radon concentration (down to total suppression with approaching moderate volcanic eruptions. The behavior of the radon activity at the Tlamacas site is more apparent, compared to other observational sites. The average level of radon release observed at the Tlamacas site is much higher, with some characteristic variations. Both the radon survey and gamma-ray spectrometry indicate intensive diffusion radon emission localized in the area of Tlamacas Mountain. The average radon concentration in the area of Tlamacas is about 10-20-fold greater than the background volcano values. The new concept of lithosphere-atmosphere coupling is presented: intensive radon release in high elevated areas shortens and modifies the Earth-to-thunderclouds electric circuit, which provokes microdischarges into the air close to the ground, attracting lightning discharges. This concept attempts to explain in a new way the noise-like geomagnetic emissions registered before major earthquakes, and it promotes interest for the study of thunderstorm activity in seismo-active zones, as a promising instrument for earthquake forecasting.

  14. Postcaldera volcanism and hydrothermal activity revealed by autonomous underwater vehicle surveys in Myojin Knoll caldera, Izu-Ogasawara arc

    Science.gov (United States)

    Honsho, Chie; Ura, Tamaki; Kim, Kangsoo; Asada, Akira

    2016-06-01

    Myojin Knoll caldera, one of the submarine silicic calderas lying on the volcanic front of the northern Izu-Ogasawara arc, has attracted increasing attention since the discovery of a large hydrothermal field called the Sunrise deposit. Although numerous submersible surveys have been conducted in Myojin Knoll caldera, they have not sufficiently explored areas to produce a complete picture of the caldera and understand the origin of the Sunrise deposit. We conducted comprehensive deep-sea surveys using an autonomous underwater vehicle and obtained high-resolution bathymetric and magnetic data and sonar images from ~70% of the caldera. The detailed bathymetric map revealed that faulting and magma eruptions, possibly associated with an inflation-deflation cycle of the magma reservoir during postcaldera volcanism, had generally occurred in the caldera wall. The main dome of the central cone was covered with lava flows and exhibits exogenous growth, which is unusual for rhyolitic domes. The magnetization distribution in the central cone indicates preferential magma intrusion along a NW-SE direction. It is presumed that magma migrated along this direction and formed a rhyolite dome at the foot of the southeastern caldera wall, where the Sunrise deposit occurs. The Sunrise deposit is composed mainly of three ridges extending in slope directions and covers ~400 × ~400 m. Magnetization reduction in the deposit area is small, indicating that the alteration zone beneath the Sunrise deposit is slanting rather than vertical. It is presumed that several slanting and near-vertical volcanic vents serve as pathways of hydrothermal fluid in Myojin Knoll caldera.

  15. Advanced Performance Modeling with Combined Passive and Active Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Dovrolis, Constantine [Georgia Inst. of Technology, Atlanta, GA (United States); Sim, Alex [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-04-15

    To improve the efficiency of resource utilization and scheduling of scientific data transfers on high-speed networks, the "Advanced Performance Modeling with combined passive and active monitoring" (APM) project investigates and models a general-purpose, reusable and expandable network performance estimation framework. The predictive estimation model and the framework will be helpful in optimizing the performance and utilization of networks as well as sharing resources with predictable performance for scientific collaborations, especially in data intensive applications. Our prediction model utilizes historical network performance information from various network activity logs as well as live streaming measurements from network peering devices. Historical network performance information is used without putting extra load on the resources by active measurement collection. Performance measurements collected by active probing is used judiciously for improving the accuracy of predictions.

  16. AAL Middleware Infrastructure for Green Bed Activity Monitoring

    Directory of Open Access Journals (Sweden)

    Filippo Palumbo

    2013-01-01

    Full Text Available This paper describes a service-oriented middleware platform for ambient assisted living and its use in two different bed activity services: bedsore prevention and sleeping monitoring. A detailed description of the middleware platform, its elements and interfaces, as well as a service that is able to classify some typical user's positions in the bed is presented. Wireless sensor networks are supposed to be widely deployed in indoor settings and on people's bodies in tomorrow's pervasive computing environments. The key idea of this work is to leverage their presence by collecting the received signal strength measured among fixed general-purpose wireless sensor devices, deployed in the environment, and wearable ones. The RSS measurements are used to classify a set of user's positions in the bed, monitoring the activities of the user, and thus supporting the bedsores and the sleep monitoring issues. Moreover, the proposed services are able to decrease the energy consumption by exploiting the context information coming from the proposed middleware.

  17. LANDSLIDE ACTIVITY MONITORING WITH THE HELP OF UNMANNED AERIAL VEHICLE

    Directory of Open Access Journals (Sweden)

    V. Peterman

    2015-08-01

    Full Text Available This paper presents a practical example of a landslide monitoring through the use of a UAV - tracking and monitoring the movements of the Potoska Planina landslide located above the village of Koroska Bela in the western Karavanke Mountains in north-western Slovenia. Past geological research in this area indicated slope landmass movement of more than 10 cm per year. However, much larger movements have been detected since - significant enough to be observed photogrammetrically with the help of a UAV. With the intention to assess the dynamics of the landslide we have established a system of periodic observations carried out twice per year – in mid-spring and mid-autumn. This paper offers an activity summary along with the presentation of data acquisition, data processing and results.

  18. Landslide Activity Monitoring with the Help of Unmanned Aerial Vehicle

    Science.gov (United States)

    Peterman, V.

    2015-08-01

    This paper presents a practical example of a landslide monitoring through the use of a UAV - tracking and monitoring the movements of the Potoska Planina landslide located above the village of Koroska Bela in the western Karavanke Mountains in north-western Slovenia. Past geological research in this area indicated slope landmass movement of more than 10 cm per year. However, much larger movements have been detected since - significant enough to be observed photogrammetrically with the help of a UAV. With the intention to assess the dynamics of the landslide we have established a system of periodic observations carried out twice per year - in mid-spring and mid-autumn. This paper offers an activity summary along with the presentation of data acquisition, data processing and results.

  19. Atmospheric chemistry in volcanic plumes.

    Science.gov (United States)

    von Glasow, Roland

    2010-04-13

    Recent field observations have shown that the atmospheric plumes of quiescently degassing volcanoes are chemically very active, pointing to the role of chemical cycles involving halogen species and heterogeneous reactions on aerosol particles that have previously been unexplored for this type of volcanic plumes. Key features of these measurements can be reproduced by numerical models such as the one employed in this study. The model shows sustained high levels of reactive bromine in the plume, leading to extensive ozone destruction, that, depending on plume dispersal, can be maintained for several days. The very high concentrations of sulfur dioxide in the volcanic plume reduces the lifetime of the OH radical drastically, so that it is virtually absent in the volcanic plume. This would imply an increased lifetime of methane in volcanic plumes, unless reactive chlorine chemistry in the plume is strong enough to offset the lack of OH chemistry. A further effect of bromine chemistry in addition to ozone destruction shown by the model studies presented here, is the oxidation of mercury. This relates to mercury that has been coemitted with bromine from the volcano but also to background atmospheric mercury. The rapid oxidation of mercury implies a drastically reduced atmospheric lifetime of mercury so that the contribution of volcanic mercury to the atmospheric background might be less than previously thought. However, the implications, especially health and environmental effects due to deposition, might be substantial and warrant further studies, especially field measurements to test this hypothesis.

  20. Ambulation monitoring of transtibial amputation subjects with patient activity monitor versus pedometer.

    Science.gov (United States)

    Dudek, Nancy L; Khan, Omar D; Lemaire, Edward D; Marks, Meridith B; Saville, Leyana

    2008-01-01

    Our study aimed to compare the accuracy of step count and ambulation distance determined with the Yamax Digi-Walker SW-700 pedometer (DW) and the Ossur patient activity monitor (PAM) in 20 transtibial amputation subjects who were functioning at the K3 Medicare Functional Classification Level. Subjects completed four simulated household tasks in an apartment setup and a gymnasium walking course designed to simulate outdoor walking without the presence of environmental barriers or varied terrain. The mean step count accuracy of the DW and the PAM was equivalent for both the household activity (75.3% vs 70.6%) and the walking course (93.8% vs 94.0%). The mean distance measurement accuracy was better with the DW than with the PAM (household activity: 72.8% vs 0%, walking course: 92.5% vs 86.3%; p < 0.05). With acceptable step count accuracy, both devices are appropriate for assessing relatively continuous ambulation. The DW may be preferred for its more accurate distance measurements. Neither device is ideal for monitoring in-home ambulation.

  1. 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.

  2. Pore Fluid Evolution Influenced by Volcanic Activities and Related Diagenetic Processes in a Rift Basin: Evidence from the Paleogene Medium-Deep Reservoirs of Huanghekou Sag, Bohai Bay Basin, China

    Directory of Open Access Journals (Sweden)

    Zhongheng Sun

    2017-01-01

    Full Text Available Volcanic activities exert a significant influence on pore fluid property and related diagenetic processes that substantially controlled reservoirs quality. Analysis of Paleogene medium-deep sandstones on the Huanghekou Sag provides insight into relating the diagenetic processes to pore fluid property evolution influenced by volcanic activities. Three distinct types of pore fluids were identified on the basis of an integrated and systematic analysis including core and thin section observation, XRD, SEM, CL, and trace element. Alkaline aqueous medium environment occurred in E2s1+2 where volcanic activities have insignificant influence on pore fluids, evidenced by typical alkaline diagenetic events such as K-feldspar albitization, quartz dissolution, feldspar dissolution, and carbonate cementation. During the deposition of E3d3, influx of terrestrial freshwater and alteration of ferromagnesian-rich pore water result in the formation of mixing aqueous medium environment through volcanic eruption dormancy causing zeolite dissolution, clay mineral transformation, and K-feldspar albitization. Ferromagnesian-rich aqueous medium environment developed resulting from the intensive hydrolysis of the unstable ferromagnesian minerals formed due to intense volcanic activities during E3d1+2 and corresponding predominant diagenetic processes were characterized by the precipitation and dissolution of low-silica zeolites. Therefore, the differential properties of pore fluids caused various diagenetic processes controlling reservoir quality.

  3. Long term continuous radon monitoring in a seismically active area

    CERN Document Server

    Piersanti, A; Galli, G

    2015-01-01

    We present the results of a long term, continuous radon monitoring experiment started in April 2010 in a seismically active area, affected during the 2010-2013 data acquisition time window by an intense micro seismic activity and by several small seismic events. We employed both correlation and cross-correlation analyses in order to investigate possible relationship existing between the collected radon data, seismic events and meteorological parameters. Our results do not support the feasibility of a robust one-to-one association between the small magnitude earthquakes characterizing the local seismic activity and single radon measurement anomalies, but evidence significant correlation patterns between the spatio-temporal variations of seismic moment release and soil radon emanations, the latter being anyway dominantly modulated by meteorological parameters variations.

  4. Ferroelectric thin-film active sensors for structural health monitoring

    Science.gov (United States)

    Lin, Bin; Giurgiutiu, Victor; Yuan, Zheng; Liu, Jian; Chen, Chonglin; Jiang, Jiechao; Bhalla, Amar S.; Guo, Ruyan

    2007-04-01

    Piezoelectric wafer active sensors (PWAS) have been proven a valuable tool in structural health monitoring. Piezoelectric wafer active sensors are able to send and receive guided Lamb/Rayleigh waves that scan the structure and detect the presence of incipient cracks and structural damage. In-situ thin-film active sensor deposition can eliminate the bonding layer to improve the durability issue and reduce the acoustic impedance mismatch. Ferroelectric thin films have been shown to have piezoelectric properties that are close to those of single-crystal ferroelectrics but the fabrication of ferroelectric thin films on structural materials (steel, aluminum, titanium, etc.) has not been yet attempted. In this work, in-situ fabrication method of piezoelectric thin-film active sensors arrays was developed using the nano technology approach. Specification for the piezoelectric thin-film active sensors arrays was based on electro-mechanical-acoustical model. Ferroelectric BaTiO3 (BTO) thin films were successfully deposited on Ni tapes by pulsed laser deposition under the optimal synthesis conditions. Microstructural studies by X-ray diffractometer and transmission electron microscopy reveal that the as-grown BTO thin films have the nanopillar structures with an average size of approximately 80 nm in diameter and the good interface structures with no inter-diffusion or reaction. The dielectric and ferroelectric property measurements exhibit that the BTO films have a relatively large dielectric constant, a small dielectric loss, and an extremely large piezoelectric response with a symmetric hysteresis loop. The research objective is to develop the fabrication and optimum design of thin-film active sensor arrays for structural health monitoring applications. The short wavelengths of the micro phased arrays will permit the phased-array imaging of smaller parts and smaller damage than is currently not possible with existing technology.

  5. Nature, Source and Composition of Volcanic Ash in Surficial Sediments Around the Zhongsha Islands

    Institute of Scientific and Technical Information of China (English)

    YAN Quanshu; SHI Xuefa; WANG Xinyu

    2008-01-01

    Volcanic detrital sediments are a unique indicator for reconstructing the petrogenetie evolution of submarine volcanic terrains. Volcanic ash in surficial sediments around the Zhongsha Islands includes three kinds of volcanogenic detritus, i.e., brown volcanic glass, colorless volcanic glass and volcanic scoria. The major element characteristics show that bimodal volcanic activity may have taken place in the northern margin of the South China Sea, with brown volcanic glass and colorless volcanic glass repre-senting the maric end-member and felsie end-member, respectively. Fractional crystallization is the main process for magma evolu-tion. The nature of the volcanic activity implies that the origin of volcanic activity was related to extensional tectonic settings, which is corresponding to an extensional geodynamie setting in the Xisha Trench, and supports the notion, which is based on geophysical data and petrology, that there may exist a mantle plume around the Hainan Island.

  6. Passive and Active Sensing Technologies for Structural Health Monitoring

    Science.gov (United States)

    Do, Richard

    A combination of passive and active sensing technologies is proposed as a structural health monitoring solution for several applications. Passive sensing is differentiated from active sensing in that with the former, no energy is intentionally imparted into the structure under test; sensors are deployed in a pure detection mode for collecting data mined for structural health monitoring purposes. In this thesis, passive sensing using embedded fiber Bragg grating optical strain gages was used to detect varying degrees of impact damage using two different classes of features drawn from traditional spectral analysis and auto-regressive time series modeling. The two feature classes were compared in detail through receiver operating curve performance analysis. The passive detection problem was then augmented with an active sensing system using ultrasonic guided waves (UGWs). This thesis considered two main challenges associated with UGW SHM including in-situ wave propagation property determination and thermal corruption of data. Regarding determination of wave propagation properties, of which dispersion characteristics are the most important, a new dispersion curve extraction method called sparse wavenumber analysis (SWA) was experimentally validated. Also, because UGWs are extremely sensitive to ambient temperature changes on the structure, it significantly affects the wave propagation properties by causing large errors in the residual error in the processing of the UGWs from an array. This thesis presented a novel method that compensates for uniform temperature change by considering the magnitude and phase of the signal separately and applying a scalable transformation.

  7. Tephrochronology of the Mont-Dore volcanic Massif (Massif Central, France): new 40Ar/39Ar constraints on the Late Pliocene and Early Pleistocene activity

    Science.gov (United States)

    Nomade, Sébastien; Pastre, Jean-François; Nehlig, Pierre; Guillou, Hervé; Scao, Vincent; Scaillet, Stéphane

    2014-03-01

    The Mont-Dore Massif (500 km2), the youngest stratovolcano of the French Massif Central, consists of two volcanic edifices: the Guéry and the Sancy. To improve our knowledge of the oldest explosive stages of the Mont-Dore Massif, we studied 40Ar/39Ar-dated (through single-grain laser and step-heating experiments) 11 pyroclastic units from the Guéry stratovolcano. We demonstrate that the explosive history of the Guéry can be divided into four cycles of explosive eruption activity between 3.09 and 1.46 Ma (G.I to G.IV). We have also ascertained that deposits associated with the 3.1-3.0-Ma rhyolitic activity, which includes the 5-km3 "Grande Nappe" ignimbrite, are not recorded in the central part of the Mont-Dore Massif. All the pyroclastites found in the left bank of the Dordogne River belong to a later explosive phase (2.86-2.58 Ma, G.II) and were channelled down into valleys or topographic lows where they are currently nested. This later activity also gave rise to most of the volcanic products in the Perrier Plateau (30 km east of the Mont-Dore Massif); three quarters of the volcano-sedimentary sequence (up to 100 m thick) was emplaced within less than 20 ky, associated with several flank collapses in the northeastern part of the Guéry. The age of the "Fournet flora" (2.69 ± 0.01 Ma) found within an ash bed belonging to G.II suggests that temperate forests already existed in the French Massif Central before the Pliocene/Pleistocene boundary. The Guéry's third explosive eruption activity cycle (G.III) lasted between 2.36 and 1.91 Ma. It encompassed the Guéry Lake and Morangie pumice and ash deposits, as well as seven other important events recorded as centimetric ash beds some 60 to 100 km southeast of the Massif in the Velay region. We propose a general tephrochronology for the Mont-Dore stratovolcano covering the last 3.1 My. This chronology is based on 44 40Ar/39Ar-dated events belonging to eight explosive eruption cycles each lasting between 100 and 200

  8. Local to global: a collaborative approach to volcanic risk assessment

    Science.gov (United States)

    Calder, Eliza; Loughlin, Sue; Barsotti, Sara; Bonadonna, Costanza; Jenkins, Susanna

    2017-04-01

    -economic conditions tending to influence longer term well-being and recovery. The volcanological community includes almost 100 Volcano Observatories worldwide, the official institutions responsible for monitoring volcanoes. They may be dedicated institutions, or operate from national institutions (geological surveys, universities, met agencies). They have a key role in early warning, forecasting and long term hazard assessment (often in the form of volcanic hazards maps). The complexity of volcanic systems means that once unrest begins there are multiple potential eruptive outcomes and short term forecasts can change rapidly. This local knowledge of individual volcanoes underpins hazard and risk assessments developed at national, regional and global scales. Combining this local expertise with the knowledge of the international research community (including interdisciplinary perspectives) creates a powerful partnership. A collaborative approach is therefore needed to develop effective volcanic risk assessments at regional to global scale. The World Organisation of Volcano Observatories is a Commission of IAVCEI, alongside other Commissions such as 'Hazard and Risk' (with an active working group on volcanic hazards maps) and the 'Cities and Volcanoes' Commission. The Global Volcano Model network is a collaborative initiative developing hazards and risk information at national to global scales, underpinned by local expertise. Partners include IAVCEI, Smithsonian Institution, International Volcanic Health Hazard Network, VHub and other initiatives and institutions.

  9. Automated monitoring of activated sludge using image analysis

    OpenAIRE

    Motta, Maurício da; M. N. Pons; Roche, N; A.L. Amaral; Ferreira, E. C.; Alves, M.M.; Mota, M.; Vivier, H.

    2000-01-01

    An automated procedure for the characterisation by image analysis of the morphology of activated sludge has been used to monitor in a systematic manner the biomass in wastewater treatment plants. Over a period of one year, variations in terms mainly of the fractal dimension of flocs and of the amount of filamentous bacteria could be related to rain events affecting the plant influent flow rate and composition. Grand Nancy Council. Météo-France. Brasil. Ministério da Ciênc...

  10. Anoxic Activated Sludge Monitoring with Combined Nitrate and Titrimetric Measurements

    DEFF Research Database (Denmark)

    Petersen, B.; Gernaey, Krist; Vanrolleghem, P.A.

    2002-01-01

    An experimental procedure for anoxic activated sludge monitoring with combined nitrate and titrimetric measurements is proposed and evaluated successfully with two known carbon sources, (-)acetate and dextrose. For nitrate measurements an ion-selective nitrate electrode is applied to allow...... was with the carbon source in excess, since excess nitrate provoked nitrite build-up thereby complicating the data interpretation. A conceptual model could quantitatively describe the experimental observations and thus link the experimentally measured proton production with the consumption of electron acceptor...... and carbon source during denitrification....

  11. Noncontact monitoring of cardiorespiratory activity by electromagnetic coupling.

    Science.gov (United States)

    Teichmann, Daniel; Foussier, Jérôme; Jia, Jing; Leonhardt, Steffen; Walter, Marian

    2013-08-01

    In this paper, the method of noncontact monitoring of cardiorespiratory activity by electromagnetic coupling with human tissue is investigated. Two measurement modalities were joined: an inductive coupling sensor based on magnetic eddy current induction and a capacitive coupling sensor based on displacement current induction. The system's sensitivity to electric tissue properties and its dependence on motion are analyzed theoretically as well as experimentally for the inductive and capacitive coupling path. The potential of both coupling methods to assess respiration and pulse without contact and a minimum of thoracic wall motion was verified by laboratory experiments. The demonstrator was embedded in a chair to enable recording from the back part of the thorax.

  12. Monitoring rice farming activities in the Mekong Delta region

    Science.gov (United States)

    Nguyen, S. T.; Chen, C. F.; Chen, C. R.; Chiang, S. H.; Chang, L. Y.; Khin, L. V.

    2015-12-01

    Half of the world's population depends on rice for survival. Rice agriculture thus plays an important role in the developing world's economy. Vietnam is one of the largest rice producers and suppliers on earth and more than 80% of the exported rice was produced from the Mekong Delta region, which is situated in the southwestern Vietnam and encompasses approximately 40,000 km2. Changes in climate conditions could likely trigger the increase of insect populations and rice diseases, causing the potential loss of rice yields. Monitoring rice-farming activities through crop phenology detection can provide policymakers with timely strategies to mitigate possible impacts on the potential yield as well as rice grain exports to ensure food security for the region. The main objective of this study is to develop a logistic-based algorithm to investigate rice sowing and harvesting activities from the multi-temporal Moderate Resolution Imaging Spectroradiometer (MODIS)-Landsat fusion data. We processed the data for two main cropping seasons (i.e., winter-spring and summer-autumn seasons) through a three-step procedure: (1) MODIS-Landsat data fusion, (2) construction of the time-series enhanced vegetation index 2 (EVI2) data, (3) rice crop phenology detection. The EVI2 data derived from the fusion results between MODIS and Landsat data were compared with that of Landsat data indicated close correlation between the two datasets (R2 = 0.93). The time-series EVI2 data were processed using the double logistic method to detect the progress of sowing and harvesting activities in the region. The comparisons between the estimated sowing and harvesting dates and the field survey data revealed the root mean squared error (RMSE) values of 8.4 and 5.5 days for the winter-spring crop and 9.4 and 12.8 days for the summer-autumn crop, respectively. This study demonstrates the effectiveness of the double logistic-based algorithm for rice crop monitoring from temporal MODIS-Landsat fusion data

  13. Validity of physical activity monitors in adults participating in free-living activities

    DEFF Research Database (Denmark)

    Berntsen, S; Hageberg, R; Aandstad, A

    2010-01-01

    Background For a given subject, time in moderate to very vigorous intensity physical activity (MVPA) varies substantially among physical activity monitors. Objective In the present study, the primary objective, whether time in MVPA recorded with SenseWear Pro(2) Armband (Armband; BodyMedia...

  14. Stress monitoring versus microseismic ruptures in an active deep mine

    Science.gov (United States)

    Tonnellier, Alice; Bouffier, Christian; Bigarré, Pascal; Nyström, Anders; Österberg, Anders; Fjellström, Peter

    2015-04-01

    monitoring data coming from the mine in quasi-real time and facilitates information exchanges and decision making for experts and stakeholders. On the basis of these data acquisition and sharing, preliminary analysis has been started to highlight whether stress variations and seismic sources behaviour might be directly bound with mine working evolution and could improve the knowledge on the equilibrium states inside the mine. Knowing such parameters indeed will be a potential solution to understand better the response of deep mining activities to the exploitation solicitations and to develop, if possible, methods to prevent from major hazards such as rock bursts and other ground failure phenomena.

  15. Evidences of volcanic unrest on high-temperature fumaroles by satellite thermal monitoring: The case of Santa Ana volcano, El Salvador

    Science.gov (United States)

    Laiolo, M.; Coppola, D.; Barahona, F.; Benítez, J. E.; Cigolini, C.; Escobar, D.; Funes, R.; Gutierrez, E.; Henriquez, B.; Hernandez, A.; Montalvo, F.; Olmos, R.; Ripepe, M.; Finizola, A.

    2017-06-01

    On October 1st, 2005, Santa Ana volcano (El Salvador) underwent a VEI 3 phreatomagmatic eruption after approximately one century of rest. Casualties and damages to some of the local infrastructures and surrounding plantations were followed by the evacuation of the nearby communities. The analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) infrared data reveals that the main explosion was preceded by a one-year-long thermal unrest, associated to the development of a fumaroles field, located at the western rim of the summit crater lake. By combining space-based thermal flux and ground-based measurements (seismicity, sulfur emissions and lake temperatures), we suggest that the activity observed at Santa Ana between 2004 and 2005 was driven by the gradual intrusion of an undegassed magma body at a very shallow depth. Magma injection induced thermal anomalies associated with sustained degassing from the fumaroles field and promoted the interaction between the magmatic-hydrothermal system and the overlying water table. This process culminated into the VEI 3 phreatomagmatic eruption of October 2005 that strongly modified the shallow structure of the crater area. The subsequent three-years-long activity resulted from self-sealing of the fracture system and by the opening of a new fracture network directly connecting the deeper hydrothermal system with the crater lake. Our results show that satellite-based thermal data allow us to detect the expansion of the high-temperature fumarolic field. This may precede an explosive eruption and/or a lava dome extrusion. In particular, we show that thermal records can be analyzed with other geochemical (i.e. SO2 emissions) and geophysical (seismicity) data to track a shallow magmatic intrusion interacting with the surrounding hydrothermal system. This provides a remarkable support for volcano monitoring and eruption forecasting, particularly in remote areas where permanent ground data acquisition is hazardous, expensive

  16. Volcanic Eruptions and Climate

    Science.gov (United States)

    LeGrande, Allegra N.; Anchukaitis, Kevin J.

    2015-01-01

    Volcanic eruptions represent some of the most climatically important and societally disruptive short-term events in human history. Large eruptions inject ash, dust, sulfurous gases (e.g. SO2, H2S), halogens (e.g. Hcl and Hbr), and water vapor into the Earth's atmosphere. Sulfurous emissions principally interact with the climate by converting into sulfate aerosols that reduce incoming solar radiation, warming the stratosphere and altering ozone creation, reducing global mean surface temperature, and suppressing the hydrological cycle. In this issue, we focus on the history, processes, and consequences of these large eruptions that inject enough material into the stratosphere to significantly affect the climate system. In terms of the changes wrought on the energy balance of the Earth System, these transient events can temporarily have a radiative forcing magnitude larger than the range of solar, greenhouse gas, and land use variability over the last millennium. In simulations as well as modern and paleoclimate observations, volcanic eruptions cause large inter-annual to decadal-scale changes in climate. Active debates persist concerning their role in longer-term (multi-decadal to centennial) modification of the Earth System, however.

  17. Onboard Processing of Multispectral and Hyperspectral Data of Volcanic Activity for Future Earth-Orbiting and Planetary Missions

    Science.gov (United States)

    Davies, Ashley Gerard; Chien, Steve; Tran, Daniel Q.; Doubleday, Joshua

    2010-01-01

    Autonomous onboard processing of data allows rapid response to detections of dynamic, changing processes. Software that can detect volcanic eruptions from thermal emission has been used to retask the Earth Observing 1 spacecraft to obtain additional data of the eruption. Rapid transmission of these data to the ground, and the automatic processing of the data to generated images, estimates of eruption parameters and maps of thermal structure, has allowed these products to be delivered rapidly to volcanologists to aid them in assessing eruption risk and hazard. Such applications will enhance science return from future Earth-orbiting spacecraft and also from spacecraft exploring the Solar System, or beyond, which hope to image dynamic processes. Especially in the latter case, long communication times between the spacecraft and Earth exclude a rapid response to what may be a transient process - only using onboard autonomy can the spacecraft react quickly to such an event.

  18. New-generation NASA Aura Ozone Monitoring Instrument (OMI) volcanic SO2 dataset: algorithm description, initial results, and continuation with the Suomi-NPP Ozone Mapping and Profiler Suite (OMPS)

    Science.gov (United States)

    Li, Can; Krotkov, Nickolay A.; Carn, Simon; Zhang, Yan; Spurr, Robert J. D.; Joiner, Joanna

    2017-02-01

    Since the fall of 2004, the Ozone Monitoring Instrument (OMI) has been providing global monitoring of volcanic SO2 emissions, helping to understand their climate impacts and to mitigate aviation hazards. Here we introduce a new-generation OMI volcanic SO2 dataset based on a principal component analysis (PCA) retrieval technique. To reduce retrieval noise and artifacts as seen in the current operational linear fit (LF) algorithm, the new algorithm, OMSO2VOLCANO, uses characteristic features extracted directly from OMI radiances in the spectral fitting, thereby helping to minimize interferences from various geophysical processes (e.g., O3 absorption) and measurement details (e.g., wavelength shift). To solve the problem of low bias for large SO2 total columns in the LF product, the OMSO2VOLCANO algorithm employs a table lookup approach to estimate SO2 Jacobians (i.e., the instrument sensitivity to a perturbation in the SO2 column amount) and iteratively adjusts the spectral fitting window to exclude shorter wavelengths where the SO2 absorption signals are saturated. To first order, the effects of clouds and aerosols are accounted for using a simple Lambertian equivalent reflectivity approach. As with the LF algorithm, OMSO2VOLCANO provides total column retrievals based on a set of predefined SO2 profiles from the lower troposphere to the lower stratosphere, including a new profile peaked at 13 km for plumes in the upper troposphere. Examples given in this study indicate that the new dataset shows significant improvement over the LF product, with at least 50 % reduction in retrieval noise over the remote Pacific. For large eruptions such as Kasatochi in 2008 (˜ 1700 kt total SO2) and Sierra Negra in 2005 (> 1100 DU maximum SO2), OMSO2VOLCANO generally agrees well with other algorithms that also utilize the full spectral content of satellite measurements, while the LF algorithm tends to underestimate SO2. We also demonstrate that, despite the coarser spatial and

  19. New-Generation NASA Aura Ozone Monitoring Instrument (OMI) Volcanic SO2 Dataset: Algorithm Description, Initial Results, and Continuation with the Suomi-NPP Ozone Mapping and Profiler Suite (OMPS)

    Science.gov (United States)

    Li, Can; Krotkov, Nickolay A.; Carn, Simon; Zhang, Yan; Spurr, Robert J. D.; Joiner, Joanna

    2017-01-01

    Since the fall of 2004, the Ozone Monitoring Instrument (OMI) has been providing global monitoring of volcanic SO2 emissions, helping to understand their climate impacts and to mitigate aviation hazards. Here we introduce a new-generation OMI volcanic SO2 dataset based on a principal component analysis (PCA) retrieval technique. To reduce retrieval noise and artifacts as seen in the current operational linear fit (LF) algorithm, the new algorithm, OMSO2VOLCANO, uses characteristic features extracted directly from OMI radiances in the spectral fitting, thereby helping to minimize interferences from various geophysical processes (e.g., O3 absorption) and measurement details (e.g., wavelength shift). To solve the problem of low bias for large SO2 total columns in the LF product, the OMSO2VOLCANO algorithm employs a table lookup approach to estimate SO2 Jacobians (i.e., the instrument sensitivity to a perturbation in the SO2 column amount) and iteratively adjusts the spectral fitting window to exclude shorter wavelengths where the SO2 absorption signals are saturated. To first order, the effects of clouds and aerosols are accounted for using a simple Lambertian equivalent reflectivity approach. As with the LF algorithm, OMSO2VOLCANO provides total column retrievals based on a set of predefined SO2 profiles from the lower troposphere to the lower stratosphere, including a new profile peaked at 13 km for plumes in the upper troposphere. Examples given in this study indicate that the new dataset shows significant improvement over the LF product, with at least 50% reduction in retrieval noise over the remote Pacific. For large eruptions such as Kasatochi in 2008 (approximately 1700 kt total SO2/ and Sierra Negra in 2005 (greater than 1100DU maximum SO2), OMSO2VOLCANO generally agrees well with other algorithms that also utilize the full spectral content of satellite measurements, while the LF algorithm tends to underestimate SO2. We also demonstrate that, despite the

  20. Permeability and continuous gradient temperature monitoring of volcanic rocks: new insights from borehole and laboratory analysis at the Campi Flegrei caldera (Southern Italy).

    Science.gov (United States)

    Carlino, Stefano; Piochi, Monica; Tramelli, Anna; Troise, Claudia; Mormone, Angela; Montanaro, Cristian; Scheu, Bettina; Klaus, Mayer; Somma, Renato; De Natale, Giuseppe

    2016-04-01

    The pilot borehole recently drilled in the eastern caldera of Campi Flegrei (Southern Italy), during the Campi Flegrei Deep Drill Project (CFDDP) (in the framework of the International Continental Scientific Drilling Program) allowed (i) estimating on-field permeability and coring the crustal rocks for laboratory experiments, and (ii) determining thermal gradient measurements down to ca. 500 m of depth. We report here a first comparative in situ and laboratory tests to evaluate the rock permeability in the very high volcanic risk caldera of Campi Flegrei, in which ground deformations likely occur as the persistent disturbance effect of fluid circulation in the shallower geothermal system. A large amount of petro-physical information derives from outcropping welded tuffs, cores and geophysical logs from previous AGIP's drillings, which are located in the central and western part of the caldera. We discuss the expected scale dependency of rock permeability results in relation with well-stratigraphy and core lithology, texture and mineralogy. The new acquired data improve the database related to physical property of Campi Flegrei rocks, allowing a better constrain for the various fluid-dynamical models performed in the tentative to understand (and forecast) the caldera behavior. We also present the first data on thermal gradient continuously measured through 0 - to 475 m of depth by a fiber optic sensor installed in the CFDDP pilot hole. As regards, we show that the obtained values of permeability, compared with those inferred from eastern sector of the caldera, can explain the different distribution of temperature at depth, as well as the variable amount of vapor phase in the shallow geothermal system. The measured temperatures are consistent with the distribution of volcanism in the last 15 ka.

  1. Aurorae and Volcanic Eruptions

    Science.gov (United States)

    2001-06-01

    Thermal-IR Observations of Jupiter and Io with ISAAC at the VLT Summary Impressive thermal-infrared images have been obtained of the giant planet Jupiter during tests of a new detector in the ISAAC instrument on the ESO Very Large Telescope (VLT) at the Paranal Observatory (Chile). . They show in particular the full extent of the northern auroral ring and part of the southern aurora. A volcanic eruption was also imaged on Io , the very active inner Jovian moon. Although these observations are of an experimental nature, they demonstrate a great potential for regular monitoring of the Jovian magnetosphere by ground-based telescopes together with space-based facilities. They also provide the added benefit of direct comparison with the terrestrial magnetosphere. PR Photo 21a/01 : ISAAC image of Jupiter (L-band: 3.5-4.0 µm) . PR Photo 21b/01 : ISAAC image of Jupiter (Narrow-band 4.07 µm) . PR Photo 21c/01 : ISAAC image of Jupiter (Narrow-band 3.28 µm) . PR Photo 21d/01 : ISAAC image of Jupiter (Narrow-band 3.21 µm) . PR Photo 21e/01 : ISAAC image of the Jovian aurorae (false-colour). PR Photo 21f/01 : ISAAC image of volcanic activity on Io . Addendum : The Jovian aurorae and polar haze. Aladdin Meets Jupiter Thermal-infrared images of Jupiter and its volcanic moon Io have been obtained during a series of system tests with the new Aladdin detector in the Infrared Spectrometer And Array Camera (ISAAC) , in combination with an upgrade of the ESO-developed detector control electronics IRACE. This state-of-the-art instrument is attached to the 8.2-m VLT ANTU telescope at the ESO Paranal Observatory. The observations were made on November 14, 2000, through various filters that isolate selected wavebands in the thermal-infrared spectral region [1]. They include a broad-band L-filter (wavelength interval 3.5 - 4.0 µm) as well as several narrow-band filters (3.21, 3.28 and 4.07 µm). The filters allow to record the light from different components of the Jovian atmosphere

  2. Numerical models for ground deformation and gravity changes during volcanic unrest: simulating the hydrothermal system dynamics of an active caldera

    Directory of Open Access Journals (Sweden)

    A. Coco

    2015-08-01

    changes become negative and decrease monotonically towards a steady state value. Since the physics of the investigated hydrothermal system is similar to any fluid-filled reservoir, such as oil fields or CO2 reservoirs produced by sequestration, the generic formulation of the model will allow it to be employed in monitoring and interpretation of deformation and gravity data associated with other geophysical hazards that pose a risk to human activity.

  3. Active sensors for health monitoring of aging aerospace structures

    Energy Technology Data Exchange (ETDEWEB)

    GIURGIUTIU,VICTOR; REDMOND,JAMES M.; ROACH,DENNIS P.; RACKOW,KIRK A.

    2000-02-29

    A project to develop non-intrusive active sensors that can be applied on existing aging aerospace structures for monitoring the onset and progress of structural damage (fatigue cracks and corrosion) is presented. The state of the art in active sensors structural health monitoring and damage detection is reviewed. Methods based on (a) elastic wave propagation and (b) electro-mechanical (E/M) impedance technique are cited and briefly discussed. The instrumentation of these specimens with piezoelectric active sensors is illustrated. The main detection strategies (E/M impedance for local area detection and wave propagation for wide area interrogation) are discussed. The signal processing and damage interpretation algorithms are tuned to the specific structural interrogation method used. In the high-frequency E/M impedance approach, pattern recognition methods are used to compare impedance signatures taken at various time intervals and to identify damage presence and progression from the change in these signatures. In the wave propagation approach, the acousto-ultrasonic methods identifying additional reflection generated from the damage site and changes in transmission velocity and phase are used. Both approaches benefit from the use of artificial intelligence neural networks algorithms that can extract damage features based on a learning process. Design and fabrication of a set of structural specimens representative of aging aerospace structures is presented. Three built-up specimens (pristine, with cracks, and with corrosion damage) are used. The specimen instrumentation with active sensors fabricated at the University of South Carolina is illustrated. Preliminary results obtained with the E/M impedance method on pristine and cracked specimens are presented.

  4. Source mechanisms of volcanic tsunamis.

    Science.gov (United States)

    Paris, Raphaël

    2015-10-28

    Volcanic tsunamis are generated by a variety of mechanisms, including volcano-tectonic earthquakes, slope instabilities, pyroclastic flows, underwater explosions, shock waves and caldera collapse. In this review, we focus on the lessons that can be learnt from past events and address the influence of parameters such as volume flux of mass flows, explosion energy or duration of caldera collapse on tsunami generation. The diversity of waves in terms of amplitude, period, form, dispersion, etc. poses difficulties for integration and harmonization of sources to be used for numerical models and probabilistic tsunami hazard maps. In many cases, monitoring and warning of volcanic tsunamis remain challenging (further technical and scientific developments being necessary) and must be coupled with policies of population preparedness. © 2015 The Author(s).

  5. Precursory volcanic CO2 signals from space

    Science.gov (United States)

    Schwandner, Florian M.; Carn, Simon A.; Kataoka, Fumie; Kuze, Akihiko; Shiomi, Kei; Goto, Naoki

    2016-04-01

    Identification of earliest signals heralding volcanic unrest benefits from the unambiguous detection of precursors that reflect deviation of magmatic systems from metastable background activity. Ascent and emplacement of new basaltic magma at depth may precede eruptions by weeks to months. Transient localized carbon dioxide (CO2) emissions stemming from exsolution from depressurized magma are expected, and have been observed weeks to months ahead of magmatic surface activity. Detecting such CO2 precursors by continuous ground-based monitoring operations is unfortunately not a widely implemented method yet, save a handful of volcanoes. Detecting CO2 emissions from space offers obvious advantages - however it is technologically challenging, not the least due to the increasing atmospheric burden of CO2, against which a surface emission signal is hard to discern. In a multi-year project, we have investigated the feasibility of space-borne detection of pre-eruptive volcanic CO2 passive degassing signals using observations from the Greenhouse Gas Observing SATellite (GOSAT). Since 2010, we have observed over 40 active volcanoes from space using GOSAT's special target mode. Over 72% of targets experienced at least one eruption over that time period, demonstrating the potential utility of space-borne CO2 observations in non-imaging target-mode (point source monitoring mode). While many eruption precursors don't produce large enough CO2 signals to exceed space-borne detection thresholds of current satellite sensors, some of our observations have nevertheless already shown significant positive anomalies preceding eruptions at basaltic volcanoes. In 2014, NASA launched its first satellite dedicated to atmospheric CO2 observation, the Orbiting Carbon Observatory (OCO-2). Its observation strategy differs from the single-shot GOSAT instrument. At the expense of GOSAT's fast time series capability (3-day repeat cycle, vs. 16 for OCO-2), its 8-footprint continuous swath can slice

  6. Frequency based detection and monitoring of small scale explosive activity by comparing satellite and ground based infrared observations at Stromboli Volcano, Italy

    Science.gov (United States)

    Worden, Anna; Dehn, Jonathan; Ripepe, Maurizio; Donne, Dario Delle

    2014-08-01

    Thermal activity is a common precursor to explosive volcanic activity. The ability to use these thermal precursors to monitor the volcano and obtain early warning about upcoming activity is beneficial for both human safety and infrastructure security. By using a very reliably active volcano, Stromboli Volcano in Italy, a method has been developed and tested to look at changes in the frequency of small scale explosive activity and how this activity changes prior to larger, ash producing explosive events. Thermal camera footage was used to designate parameters for typical explosions at Stromboli (size of spatter field, cooling rate, frequency of explosions) and this information was applied to characterize explosions in satellite imagery. Satellite data from The National Aeronautics and Space Administration's Moderate Resolution Imaging Spectroradiometer (MODIS) and US/Japan designed Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) for numerous periods in 2002 to 2009 were analyzed for thermal features which were used to calculate an estimate of the level of activity during the given time period. The results at Stromboli showed a high level of small scale explosions which stop completely prior to large paroxysmal eruptive episodes. This activity also corresponds well to seismic and infrasonic records at Stromboli, indicating that this thermal infrared monitoring method may be used in conjunction with other detection methods where available, and also indicates that it may be a useful method for volcano monitoring when other methods (e.g. seismic instrumentation, infrasound arrays, etc.) are not available.

  7. Passive and Active Monitoring on a High Performance Research Network.

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, Warren

    2001-05-01

    The bold network challenges described in ''Internet End-to-end Performance Monitoring for the High Energy and Nuclear Physics Community'' presented at PAM 2000 have been tackled by the intrepid administrators and engineers providing the network services. After less than a year, the BaBar collaboration has collected almost 100 million particle collision events in a database approaching 165TB (Tera=10{sup 12}). Around 20TB has been exported via the Internet to the BaBar regional center at IN2P3 in Lyon, France, for processing and around 40 TB of simulated events have been imported to SLAC from Lawrence Livermore National Laboratory (LLNL). An unforseen challenge has arisen due to recent events and highlighted security concerns at DoE funded labs. New rules and regulations suggest it is only a matter of time before many active performance measurements may not be possible between many sites. Yet, at the same time, the importance of understanding every aspect of the network and eradicating packet loss for high throughput data transfers has become apparent. Work at SLAC to employ passive monitoring using netflow and OC3MON is underway and techniques to supplement and possibly replace the active measurements are being considered. This paper will detail the special needs and traffic characterization of a remarkable research project, and how the networking hurdles have been resolved (or not!) to achieve the required high data throughput. Results from active and passive measurements will be compared, and methods for achieving high throughput and the effect on the network will be assessed along with tools that directly measure throughput and applications used to actually transfer data.

  8. A quantitative geomorphological approach to constraining the volcanic and tectonic evolution of the active Dabbahu rift segment, Afar, Ethiopia.

    Science.gov (United States)

    Medynski, Sarah; Pik, Raphaël; Burnard, Peter; Vye-Brown, Charlotte; Blard, Pierre-Henri; France, Lydéric; Dumont, Stéphanie; Grandin, Raphaël; Schimmelpfennig, Irene; Benedetti, Lucilla; Ayalew, Dereje; Yirgu, Gezahegn

    2013-04-01

    In the Afar depression (Ethiopia), extension is organised along rift segments that morphologically resemble oceanic rifts. Segmentation results from interactions between dyke injection and volcanism, as observed during the well-documented 2005 rifting event on the Dabbahu rift segment. This tectono-volcanic crisis was observed in detail via remote sensing techniques, providing invaluable information on the present-day tectonic - magmatic interplay during a sequence of dyke intrusions. However, lack of data remains on timescales of 1 to 100 kyr, the period over which the main morphology of the rift is acquired. The Dabbahu rift segment represents an ideal natural laboratory to study the evolution of rift morphology as a response to volcanic and tectonic influences. We use cosmogenic nuclides (3He and 36Cl) to determine the ages of young (<100 kyr) lava flows and to date the initiation and movement of fault scarps, which cut the lavas. Where possible, we analysed vertical profiles along fault scarps, in an attempt to distinguish individual tectonic events that offset the scarp, estimate their amplitudes and date the recurrence intervals. These geochronological constraints, combined with major & trace element compositions, field mapping and digital mapping (Landsat, ASTER and SPOT imagery), provide valuable insights on the magmatic and tectonic history of the segment. The results show that over the last 100 ka, the northern part of the Dabbahu segment was supplied by at least two different magma reservoirs, which can be identified from their distinctive chemistries. The main reservoir is located beneath Dabbahu volcano at the northern tip of the rift segment, and has been supplied with magma for at least 72 ka. The second reservoir is located further south on the rift axis and corresponds to the current mid-segment magma chamber, which was responsible for the 2005 rifting episode. Two magmatic cycles linked to the Dabbahu magma chamber were recorded, lasting 20-30 kyr

  9. Sphene (Titanite) as Both Monitor and Driver of Evolution of Felsic Magma: Miocene Volcanic Plutonic and Rocks of the Colorado River Region, NV-AZ, USA

    Science.gov (United States)

    Miller, C. F.; Colombini, L. L.; Wooden, J. L.; Mazdab, F. K.; Gualda, G. A.; Claiborne, L. E.; Ayers, J. C.

    2009-05-01

    Sphene is commonly the most abundant accessory mineral in metaluminous to weakly peraluminous igneous rocks. Its relatively large crystals preserve a wide array of zoning patterns and inclusions - notably, abundant other accessories and melt inclusions - and it is a major host for REE, U, Th, and HFSE. Thus it is a valuable repository of information about the history of the magmas from which it forms. Recent development of a Zr-in- sphene thermometer (Hayden et al CMP 155:529 2008) and of sensitive and precise in situ trace element analysis by SHRIMP-RG (Mazdab et al GSA abst 39:6:406 2007) permit more powerful exploitation of this repository. We have initiated a study of sphene in Miocene intrusive and extrusive rocks of the Colorado River extensional corridor for which extensive field, geochemical, and geochronological data provide context. Sphene is present as a late interstitial phase in some gabbros and diorites and common in quartz monzonites and granites. Among extrusive rocks, it occurs as phenocrysts in rhyolite lavas and tuffs that are products of small to giant eruptions (Peach Spring Tuff, >600 km3). Glasses that host sphene in the rhyolites are highly evolved (>76 wt% SiO2). Applying the Zr-in-sphene thermometer (TZr), SHRIMP-RG analyses indicate crystallization T between 730 and 810 C in both plutonic and volcanic rocks. This range is narrower than T estimates for zircon growth (Ti thermometry) for the same suite, which extend to somewhat lower and considerably higher values; zircons also tend to record more events and, evidently, longer histories. Ranges of REE patterns are variable and to some extent sample-specific, but all reveal common characteristics: (1) extremely high concentrations, especially for middle REE (maximum Sm in interiors 10-40x103 x chondrite); (2) deep negative Eu anomalies (Eu/Eu* ca. 0.1-0.2); (3) TZr and REE dropping toward rims - especially pronounced for MREE. Estimated Kds for REE from sphene rims and rhyolite glass or

  10. Recurrence models of volcanic events: Applications to volcanic risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Crowe, B.M. [Los Alamos National Lab., Las Vegas, NV (United States); Picard, R.; Valentine, G. [Los Alamos National Lab., NM (United States); Perry, F.V. [New Mexico Univ., Albuquerque, NM (United States)

    1992-03-01

    An assessment of the risk of future volcanism has been conducted for isolation of high-level radioactive waste at the potential Yucca Mountain site in southern Nevada. Risk used in this context refers to a combined assessment of the probability and consequences of future volcanic activity. Past studies established bounds on the probability of magmatic disruption of a repository. These bounds were revised as additional data were gathered from site characterization studies. The probability of direct intersection of a potential repository located in an eight km{sup 2} area of Yucca Mountain by ascending basalt magma was bounded by the range of 10{sup {minus}8} to 10{sup {minus}10} yr{sup {minus}1 2}. The consequences of magmatic disruption of a repository were estimated in previous studies to be limited. The exact releases from such an event are dependent on the strike of an intruding basalt dike relative to the repository geometry, the timing of the basaltic event relative to the age of the radioactive waste and the mechanisms of release and dispersal of the waste radionuclides in the accessible environment. The combined low probability of repository disruption and the limited releases associated with this event established the basis for the judgement that the risk of future volcanism was relatively low. It was reasoned that that risk of future volcanism was not likely to result in disqualification of the potential Yucca Mountain site.

  11. Drought monitoring with soil moisture active passive (SMAP) measurements

    Science.gov (United States)

    Mishra, Ashok; Vu, Tue; Veettil, Anoop Valiya; Entekhabi, Dara

    2017-09-01

    Recent launch of space-borne systems to estimate surface soil moisture may expand the capability to map soil moisture deficit and drought with global coverage. In this study, we use Soil Moisture Active Passive (SMAP) soil moisture geophysical retrieval products from passive L-band radiometer to evaluate its applicability to forming agricultural drought indices. Agricultural drought is quantified using the Soil Water Deficit Index (SWDI) based on SMAP and soil properties (field capacity and available water content) information. The soil properties are computed using pedo-transfer function with soil characteristics derived from Harmonized World Soil Database. The SMAP soil moisture product needs to be rescaled to be compatible with the soil parameters derived from the in situ stations. In most locations, the rescaled SMAP information captured the dynamics of in situ soil moisture well and shows the expected lag between accumulations of precipitation and delayed increased in surface soil moisture. However, the SMAP soil moisture itself does not reveal the drought information. Therefore, the SMAP based SWDI (SMAP_SWDI) was computed to improve agriculture drought monitoring by using the latest soil moisture retrieval satellite technology. The formulation of SWDI does not depend on longer data and it will overcome the limited (short) length of SMAP data for agricultural drought studies. The SMAP_SWDI is further compared with in situ Atmospheric Water Deficit (AWD) Index. The comparison shows close agreement between SMAP_SWDI and AWD in drought monitoring over Contiguous United States (CONUS), especially in terms of drought characteristics. The SMAP_SWDI was used to construct drought maps for CONUS and compared with well-known drought indices, such as, AWD, Palmer Z-Index, sc-PDSI and SPEI. Overall the SMAP_SWDI is an effective agricultural drought indicator and it provides continuity and introduces new spatial mapping capability for drought monitoring. As an

  12. Activity monitor intervention to promote physical activity of physicians-in-training: randomized controlled trial.

    Directory of Open Access Journals (Sweden)

    Anne N Thorndike

    Full Text Available BACKGROUND: Physicians are expected to serve as role models for healthy lifestyles, but long work hours reduce time for healthy behaviors. A hospital-based physical activity intervention could improve physician health and increase counseling about exercise. METHODS: We conducted a two-phase intervention among 104 medical residents at a large hospital in Boston, Massachusetts. Phase 1 was a 6-week randomized controlled trial comparing daily steps of residents assigned to an activity monitor displaying feedback about steps and energy consumed (intervention or to a blinded monitor (control. Phase 2 immediately followed and was a 6-week non-randomized team steps competition in which all participants wore monitors with feedback. Phase 1 outcomes were: 1 median steps/day and 2 proportion of days activity monitor worn. The Phase 2 outcome was mean steps/day on days monitor worn (≥500 steps/day. Physiologic measurements were collected at baseline and study end. Median steps/day were compared using Wilcoxon rank-sum tests. Mean steps were compared using repeated measures regression analyses. RESULTS: In Phase 1, intervention and control groups had similar activity (6369 vs. 6063 steps/day, p = 0.16 and compliance with wearing the monitor (77% vs. 77% of days, p = 0.73. In Phase 2 (team competition, residents recorded more steps/day than during Phase 1 (CONTROL: 7,971 vs. 7,567, p = 0.002; INTERVENTION: 7,832 vs. 7,739, p = 0.13. Mean compliance with wearing the activity monitor decreased for both groups during Phase 2 compared to Phase 1 (60% vs. 77%, p<0.001. Mean systolic blood pressure decreased (p = 0.004 and HDL cholesterol increased (p<0.001 among all participants at end of study compared to baseline. CONCLUSIONS: Although the activity monitor intervention did not have a major impact on activity or health, the high participation rates of busy residents and modest changes in steps, blood pressure, and HDL suggest that more

  13. Elastic plate flexure above mantle plumes explains the upstream offset of volcanic activity at la Réunion and Hawaii

    Science.gov (United States)

    Gerbault, Muriel; Fontaine, Fabrice; Rabinowicz, Michel; Bystricky, Micha

    2017-04-01

    Surface volcanism at la Réunion and Hawaii occurs with an offset of 150-180 km upstream to the plume axis with respect to the plate motion. This striking observation raises questions about the forcing of plume-lithosphere thermo-mechanical interactions on melt trajectories beneath these islands. Based on visco-elasto-plastic numerical models handled at kilometric resolution, we propose to explain this offset by the development of compressional stresses at the base of the lithosphere, that result from elastic plate bending above the upward load exerted by the plume head. This horizontal compression adopts a disc shape centered around the plume axis, 20 km thick and 150 km in radius, at 50-70 km depth where the temperature varies from 600°C to 750°C. It lasts for 5 to 10 My in an oceanic plate of age greater than 70 My, a timing that is controlled by the visco-elastic relaxation time at 50-70 km depth. This period of time exceeds the time during which both the Somalian/East-African and Pacific plates drift over the Reunion and Hawaii plumes, respectively, thus rendering this basal compression a persistent feature. It is inferred that the buoyant melts percolating in the plume head pond below this zone of compression and eventually spread laterally until the most compressive principal elastic stresses reverse to the vertical, i.e., 150 km away from the plume head. There, melts propagate through dikes upwards to 35 km depth, where the plate curvature reverses and ambient compression diminishes. This 30-35 km depth may thus host magmatic reservoirs where melts pond, until further differentiation can relaunch ascension up to the surface and form a volcanic edifice. In a second stage, as the volcano grows because of melt accumulation at the top of the plate, the lithosphere is flexed downwards, inducing extra tensile stress at 30-35 km depth and compression at 15 km depth. It implies that now the melts pond at 15 km and form another magmatic reservoir lying just

  14. 大兴安岭-太行山重力梯度带以西的第四纪火山活动%Quaternary Volcanic Activities in the West of the Daxing′anling-Taihangshan Gravity Lineament

    Institute of Scientific and Technical Information of China (English)

    樊祺诚; 赵勇伟; 陈生生; 李霓; 隋建立

    2015-01-01

    Quaternary volcanic activities in the west of the Daxing'anling-Taihangshan gravity lineament stretch,from north to south,across two different geotectonic setting,the Xing'an Mongolian orogenic belt and the North China Craton.The volcanic activities generated three volcanic clusters with various sizes:Nuominhe volcanic cluster and Chaoerhe-Halahahe volcanic cluster in the north,Abaga volcanic cluster and Dalinuoer volcanic cluster in the middle,and Datong volcanic cluster and Wulanhada volcanic cluster in the south.These volcanic clusters consist mainly of monogenetic volcanos with the cone number from dozens to more than 200.For example,the Abaga-Dalinuoer volcanic field in Inner Mongolia ex-tends northwestward into the adjacent Dariganga lava plateau of Mongolia,forming the largest Cenozoic volcanic fields in eastern Asia.Thus,the west of Daxing'anling-Taihangshan gravity lineament is a key place to (1 )discuss origin and tec-tonic setting of intra-continent volcanic activity,and (2)study differential evolutions between the east and west sides of the Daxing'anling-Taihangshan gravity lineament and between the Xing'an Mongolian orogenic belt and the North China Craton.%大兴安岭—太行山重力梯度带以西的第四纪火山活动自北往南贯穿兴蒙造山带和华北克拉通2个大地构造单元,可以分为北、中、南三部分,展现规模不等的火山群:北部诺敏河火山群和绰尔河—哈拉哈河火山群,中部阿巴嘎火山群和达里诺尔火山群,南部大同火山群和乌兰哈达火山群。这些火山群主要由单成因火山组成,少则几十座,多则200余座,如阿巴嘎火山群向北延入蒙古达里干加,构成亚洲东部面积最大的新生代火山区。因此,大兴安岭—太行山重力梯度带以西的第四纪火山成为探讨大陆内部火山活动构造背景与成因机制的重要场所,也是获取大兴安岭—太行山重力梯度带东西两侧和兴

  15. Nanosensors for a Monitoring System in Intelligent and Active Packaging

    Directory of Open Access Journals (Sweden)

    Guillermo Fuertes

    2016-01-01

    Full Text Available A theoretical wireless nanosensor network (WNSN system that gives information about the food packaging condition is proposed. The protection effectiveness is estimated by measuring many factors, such as the existence of microorganisms, bacteria, gases, and contaminants. This study is focused on the detection of an antimicrobial agent (AA attached on a polymer forming an active integrated package. All monitoring technologies for food conservation are analyzed. Nanobiosensor nanomachine (NM, which converts biological or chemical signals into electrical signals, is used. A mathematical model, which describes the constituent’s emigration from the package to food, is programmed in MatLab software. The results show three nanobiosensors forming a WNSN. The nanobiosensors are able to carry out the average concentration for different spots in the package. This monitoring system shows reading percentages in three degrees and different colors: excellent (green, good (cyan, and lacking (red. To confirm the utility of the model, different simulations are performed. Using the WNSNs, results of AA existing in food package (FP through time were successfully obtained.

  16. Double, double, (but mostly) toil, and trouble: A multidisciplinary approach to quantify the permeability of an active volcanic hydrothermal system (Whakaari volcano, New Zealand)

    Science.gov (United States)

    Heap, Michael; Kennedy, Ben; Farquharson, Jamie; Ashworth, James; Mayer, Klaus; Letham-Brake, Mark; Reuschlé, Thierry; Gilg, Albert; Scheu, Betty; Lavallée, Yan; Siratovich, Paul; Cole, Jim; Jolly, Art; Dingwell, Donald

    2016-04-01

    Our multidisciplinary approach, which combines field techniques and traditional laboratory methods, aims to better understand the permeability of an active volcanic hydrothermal system, a vital prerequisite for understanding and modelling the behaviour of hydrothermal systems worldwide. Whakaari volcano (an active stratovolcano located 48 km off New Zealand's North Island) hosts an open, highly reactive hydrothermal system (hot springs and mud pools, fumaroles, acid streams and lakes) and represents an ideal natural laboratory to undertake such a study. We first gained an appreciation of the different lithologies at Whakaari and (where possible) their lateral and vertical extent through reconnaissance by land, sea, and air. Due to the variable nature of these altered lithologies (mainly lavas and tuffs), we measured porosity-permeability for in excess of a hundred rock hand samples using field techniques. We also measured the permeability of recent, unconsolidated deposits using a field soil permeameter. Our field measurements were then groundtruthed on a subset of these samples (~40-50) using traditional laboratory techniques: helium pycnometry and measurements of permeability using a benchtop permeameter, including measurements under increasing confining pressure (i.e., depth). In all, our measurements highlight that the porosity of the materials at Whakaari can vary from ~0.01 to ~0.6, and permeability can vary by eight orders of magnitude. However, our data show no discernable trend between porosity and permeability. A combination of macroscopic and microscopic observations, chemistry (XRF), mineralogy (XRD), and mercury porosimetry highlight that the absence of a robust porosity-permeability relationship is the product of an insane variability in alteration and microstructure (pore size, particle size, pore connectivity, presence/absence of microcracks, layering, amongst others). While our systematic study offers the most complete porosity-permeability dataset

  17. Seismic activity and stress tensor inversion at Las Tres Vírgenes Volcanic and Geothermal Field (México)

    Science.gov (United States)

    Antayhua-Vera, Yanet; Lermo-Samaniego, Javier; Quintanar-Robles, Luis; Campos-Enríquez, Oscar

    2015-10-01

    We analyze local earthquakes occurring between 2003 and 2012 at the Las Tres Vírgenes Volcanic and Geothermal Field (TVVGF) to establish their temporal and spatial distribution, and relationships with local and regional fault systems, water injection, acid stimulation and steam production tests. We obtained focal mechanisms and inverted data for the stress tensor to understand the local and regional stress fields. We analyzed 423 local earthquakes with magnitudes between 0.1 and 2.9 Mc and hypocentral depths from 0.2 to 7.4 km b.s.l. The cutoff depth at ~ 7.4 km possibly delineates the brittle-ductile transition zone. We identified seven swarms (from 1 to 7). Swarms 1 (December 2009), 2 (May 2010), 3 (June-July 2010) and 7 (December 2012) are strongly correlated with injection processes; whereas swarms 5 (April 2012) and 6 (September 2012) are correlated with local tectonic faults. Stress inversion showed NW-SE, E-W and NE-SW extensional orientations (Shmin), in agreement with the local tectonic stress field; while NE-SW compressional orientations (SHmax) are correlated with the regional tectonic stress field.

  18. Performance Assessment and Active System Monitoring for Refrigeration Systems

    DEFF Research Database (Denmark)

    Green, Torben

    for algorithms that ensures or improves the performance of the system. A supermarket refrigeration system is usually a complex and distributed control system, and it can therefore be difficult to assess the performance without a formal method. The main interest for a supermarket, with respect...... of the refrigeration system has been addressed in the project. The proposed methods for improvement relies on a minimum of detailed knowledge about the refrigeration system. In addition, since a refrigeration system often operates in steady state an active system monitoring setup has been proposed, to enable...... a method for assessing the operational performance at a plan-wide level and is therefore providing a tool for improving the plant-wide performance. The performance function has been used in dierent setups to improve the performance of the refrigeration system. Static and the dynamic performance...

  19. The MAGNUM (Multicolor Active Galactic NUclei Monitoring) Project

    Science.gov (United States)

    Yoshii, Y.; Kobayashi, Y.; Minezaki, T.

    2003-05-01

    The MAGNUM Project is designed to carry out long-term monitoring observations of hundreds of active galactic nuclei in the visible and near-infrared wavelength regions. In order to obtain these observations, we built a new 2m optical-infrared telescope, and located it near the Haleakala summit at a height of 3050m within the area of the University of Hawaii's Haleakala Observatory on the Hawaiian Island of Maui. The Project was funded in 1995 and preliminary observations were started early in 2001. We are working toward the realization of an unmanned, automated observatory which is suitable to relatively simple and stable observations over many years. We present an overview of the Project and its current status.

  20. Automated observatory for multicolor active galactic nuclei monitoring (MAGNUM)

    Science.gov (United States)

    Kobayashi, Yukiyasu; Yoshii, Yuzuru; Minezaki, Takeo; Enya, Keigo; Aoki, Tsutomu; Suganuma, Masahiro; Tomita, Hiroyuki; Doi, Mamoru; Motohara, Kentaro; Peterson, Bruce A.; Smith, Craig H.; Little, John K.; Greene, Ben

    2003-02-01

    We present the outline and the current status of the MAGNUM automated observation system. The operational objective of the MAGNUM Project is to carry out long-term multi-color monitoring observations of active galactic nuclei in the visible and near-infrared wavelength regions. In order to obtain these observations, we built a new 2 m optical-infrared telescope, and sited it at the University of Hawaii's Haleakala Observatory on the Hawaiian Island of Maui. Preliminary observations were started early in 2001. We are working toward the final form of the MAGNUM observation system, which is an unmanned, automated observatory. This system requirement was set by considering that the observation procedures are relatively simple, and the targets must be observed consistently over many years.

  1. Diffuse emissions of Volatile Organic Compounds (VOCs) from soil in volcanic and hydrothermal systems: evidences for the influence of microbial activity on the carbon budget

    Science.gov (United States)

    Venturi, Stefania; Tassi, Franco; Fazi, Stefano; Vaselli, Orlando; Crognale, Simona; Rossetti, Simona; Cabassi, Jacopo; Capecchiacci, Francesco

    2017-04-01

    Soils in volcanic and hydrothermal areas are affected by anomalously high concentrations of gases released from the deep reservoirs, which consists of both inorganic (mainly CO2 and H2S) and organic (volatile organic compounds; VOCs) species. VOCs in volcanic and hydrothermal fluids are mainly composed of saturated and unsaturated hydrocarbons (alkanes, aromatics, alkenes, and cyclics), with variable concentrations of O- and S-bearing compounds and halocarbons, depending on the physicochemical conditions at depth. VOCs in interstitial soil gases and fumarolic emissions from four volcanic and hydrothermal systems in the Mediterranean area (Solfatara Crater, Poggio dell'Olivo and Cava dei Selci, in Italy, and Nisyros Island, in Greece) evidenced clear compositional differences, suggesting that their behavior is strongly affected by secondary processes occurring at shallow depths and likely controlled by microbial activity. Long-chain saturated hydrocarbons were significantly depleted in interstitial soil gases with respect to those from fumarolic discharges, whereas enrichments in O-bearing compounds (e.g. aldehydes, ketones), DMSO2 and cyclics were commonly observed. Benzene was recalcitrant to degradation processes, whereas methylated aromatics were relatively instable. The chemical and isotopic (δ13C in CO2 and CH4) composition of soil gases collected along vertical profiles down to 50 cm depth at both Solfatara Crater and Poggio dell'Olivo (Italy) showed evidences of relevant oxidation processes in the soil, confirming that microbial activity likely plays a major role in modifying the composition of deep-derived VOCs. Despite their harsh conditions, being typically characterized by high temperatures, low pH, and high toxic gases and metal contents, the variety of habitats characterizing volcanic and hydrothermal environments offers ideal biomes to extremophilic microbes, whose metabolic activity can consume and/or produce VOCs. In the Solfatara Crater, microbial

  2. Volcanic evolution of an active magmatic rift segment on a 100 Kyr timescale: exposure dating of lavas from the Manda Hararo/Dabbahu segment of the Afar Rift

    Science.gov (United States)

    Medynski, S.; Williams, A.; Pik, R.; Burnard, P.; Vye, C.; France, L.; Ayalew, D.; Yirgu, G.

    2012-12-01

    activity predominates) - except during extraordinary events when dykes are long enough to reach those parts, as in 2005. The eruption ages of the different lava units correlates with their degrees of differentiation, allowing different magmatic cycles of about a few tens of years each to be distinguished. During the first recorded magmatic cycle (~70 ka to ~55 ka), Dabbahu is built of wide-spreading pāhoehoe flows around localised eruptive centres. The resulting topography of the volcanic edifice remains low, and is only slightly affected by rift-related fault activity, with the development of minor scarps. The second recorded magmatic cycle (~50 ka to ~20 ka) coincides with a strong development of Dabbahu topography - underlined by the change in lava morphology with well channelized 'a'ā flows since 50 ka. Tectonic activity also clearly increases over this period, with the initiation of the major fault scarps of the rift, which have been dated at around 35 ka. Our study underlines the role of the magma supply and availability beneath Dabbahu in the evolution both topographies of Dabbahu volcano and of the rift depression morphology.

  3. Volcanism and associated hazards: the Andean perspective

    Science.gov (United States)

    Tilling, R. I.

    2009-12-01

    Andean volcanism occurs within the Andean Volcanic Arc (AVA), which is the product of subduction of the Nazca Plate and Antarctica Plates beneath the South America Plate. The AVA is Earth's longest but discontinuous continental-margin volcanic arc, which consists of four distinct segments: Northern Volcanic Zone, Central Volcanic Zone, Southern Volcanic Zone, and Austral Volcanic Zone. These segments are separated by volcanically inactive gaps that are inferred to indicate regions where the dips of the subducting plates are too shallow to favor the magma generation needed to sustain volcanism. The Andes host more volcanoes that have been active during the Holocene (past 10 000 years) than any other volcanic region in the world, as well as giant caldera systems that have produced 6 of the 47 largest explosive eruptions (so-called "super eruptions") recognized worldwide that have occurred from the Ordovician to the Pleistocene. The Andean region's most powerful historical explosive eruption occurred in 1600 at Huaynaputina Volcano (Peru). The impacts of this event, whose eruptive volume exceeded 11 km3, were widespread, with distal ashfall reported at distances >1000 km away. Despite the huge size of the Huaynaputina eruption, human fatalities from hazardous processes (pyroclastic flows, ashfalls, volcanogenic earthquakes, and lahars) were comparatively small owing to the low population density at the time. In contrast, lahars generated by a much smaller eruption (indecisiveness by government officials, rather than any major deficiencies in scientific data. Ruiz's disastrous outcome, however, together with responses to subsequent hazardous eruptions in Chile, Colombia, Ecuador, and Peru has spurred significant improvements in reducing volcano risk in the Andean region. But much remains to be done.

  4. Volcanism and associated hazards: The Andean perspective

    Science.gov (United States)

    Tilling, R.I.

    2009-01-01

    Andean volcanism occurs within the Andean Volcanic Arc (AVA), which is the product of subduction of the Nazca Plate and Antarctica Plates beneath the South America Plate. The AVA is Earth's longest but discontinuous continental-margin volcanic arc, which consists of four distinct segments: Northern Volcanic Zone, Central Volcanic Zone, Southern Volcanic Zone, and Austral Volcanic Zone. These segments are separated by volcanically inactive gaps that are inferred to indicate regions where the dips of the subducting plates are too shallow to favor the magma generation needed to sustain volcanism. The Andes host more volcanoes that have been active during the Holocene (past 10 000 years) than any other volcanic region in the world, as well as giant caldera systems that have produced 6 of the 47 largest explosive eruptions (so-called "super eruptions") recognized worldwide that have occurred from the Ordovician to the Pleistocene. The Andean region's most powerful historical explosive eruption occurred in 1600 at Huaynaputina Volcano (Peru). The impacts of this event, whose eruptive volume exceeded 11 km3, were widespread, with distal ashfall reported at distances >1000 km away. Despite the huge size of the Huaynaputina eruption, human fatalities from hazardous processes (pyroclastic flows, ashfalls, volcanogenic earthquakes, and lahars) were comparatively small owing to the low population density at the time. In contrast, lahars generated by a much smaller eruption (indecisiveness by government officials, rather than any major deficiencies in scientific data. Ruiz's disastrous outcome, however, together with responses to subsequent hazardous eruptions in Chile, Colombia, Ecuador, and Peru has spurred significant improvements in reducing volcano risk in the Andean region. But much remains to be done.

  5. Friction in volcanic environments

    Science.gov (United States)

    Kendrick, Jackie E.; Lavallée, Yan

    2016-04-01

    to eruption behaviour and during ascent magma behaves in an increasingly rock-like manner as it degasses and crystallises. This character aids the development of shear zones in the conduit, producing fault surfaces that host gouge, cataclasite and pseudotachylyte and which control the last hundreds of meters of ascent by frictional slip. Recent work has shown that the occurrence of vesiculation of gas bubbles modifies the rheology of frictional melt and in extreme cases can trigger eruption style to switch from effusive to explosive activity. Hence it is of vital importance to recognise the frictional behaviour of volcanic rocks and magmas to understand the continuation of an eruption and associated hazards.

  6. Marsh Bird Monitoring Activities in Vermont in 1999

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report outlines a continuation of the black tern monitoring which was initiated in 1990, as well as the marsh bird monitoring program which was started in 1996....

  7. Panel Endorses Active Monitoring for Low-Risk Prostate Cancer

    Science.gov (United States)

    An independent panel convened this week by NIH has concluded that many men with localized, low-risk prostate cancer should be closely monitored, permitting treatment to be delayed until warranted by disease progression. However, monitoring strategies—such

  8. Episodic Volcanism and Geochemistry in Western Nicaragua

    Science.gov (United States)

    Saginor, I.; Carr, M. J.; Gazel, E.; Swisher, C.; Turrin, B.

    2007-12-01

    The active volcanic arc in western Nicaragua is separated from the Miocene arc by a temporal gap in the volcanic record, during which little volcanic material was erupted. Previous work suggested that this gap lasted from 7 to 1.6 Ma, during which volcanic production in Nicaragua was limited or nonexistent. Because the precise timing and duration of this gap has been poorly constrained, recent fieldwork has focused on locating samples that may have erupted close to or even during this apparent hiatus in activity. Recent 40Ar/39Ar dates reveal pulses of low- level episodic volcanism at 7 Ma and 1 Ma between the active and Miocene arcs with current volcanism beginning ~350 ka. In addition, sampling from an inactive area between Coseguina and San Cristobal yielded two distinct groupings of ages; one of Tamarindo age (13 Ma) and the other around 3.5 Ma-the only samples of that age collected on-strike with the active arc. This raises the possibility the bases of the other active volcanoes contain lavas that are older than expected, but have been covered by subsequent eruptions. The Miocene arc differs from the active arc in Central America in several ways, with the latter having higher Ba/La and U/Th values due to increased slab input and changes in subducted sediment composition. Analysis of sample C-51 and others taken from the same area may shed light on the timing of this shift from high to low Ba/La and U/Th values. More importantly, it may help explain why the arc experienced such a dramatic downturn in volcanic production during this time. We also report 25 new major and trace element analyses that shed some light on the origins of these minor episodes of Nicaraguan volcanism. These samples are currently awaiting Sr and Nd isotopic analyses.

  9. Impact of volcanic processes on the cryospheric system of the Peteroa Volcano, Andes of southern Mendoza, Argentina

    Science.gov (United States)

    Liaudat, Dario Trombotto; Penas, Pablo; Aloy, Gustavo

    2014-03-01

    Soil temperatures of the active Volcanic Complex Peteroa situated in the Cordillera Principal between Chile and Argentina at 35°15‧ S and 70°35‧ W (approximately) were monitored in the area, and local geomorphology (periglacial geomorphology, presence of permafrost, and cryoforms) was studied. The present contribution also resulted in a comparison of two consecutive analyses of the volcano peak carried out with special thermocameras (AGEMA TVH 550, FUR P660) in order to study the thermal range of different hot and cold sites selected in 2009. The thermocameras were used ascending by foot and also during flights with a Cessna 180. A night expedition to the volcanic avalanche caldera, at up to 3900 m asl (approximately), completed the monitoring activity of 2010. Hot zones were associated to present volcanism and cold zones to the presence of glacier ice and shadowy slopes with possible presence of permafrost. Identifying and mapping uncovered and covered ice was possible with the help of monitoring and geomorphological interpretation related to the upper englacement, which is severely affected by volcanism. Glaciers are retreating toward the north or approaching the rims of the volcanic avalanche caldera leaving islands of ice associated with superficial permafrost. The cryogenic area with slope permafrost was identified through active protalus and sedimentary cryogenic slopes. Craters have undergone considerable thermal changes in comparison to the year 2009; and new, much more vigorous fumaroles have appeared in hot areas detected in 2009 following a tendency toward the west. New subaquatic heat columns that appeared in crater 3, crater walls, and glaciated areas vanished, supplying cold water and thus contributing to the formation of a new lake in crater 4. A possible post-seismic shift of the volcanic activity may provide geodynamical evidence of the changes registered in other areas after the earthquake of 27 February 2010.

  10. Seismic tomography model reveals mantle magma sources of recent volcanic activity at El Hierro Island (Canary Islands, Spain)

    Science.gov (United States)

    García-Yeguas, Araceli; Ibáñez, Jesús M.; Koulakov, Ivan; Jakovlev, Andrey; Romero-Ruiz, M. Carmen; Prudencio, Janire

    2014-12-01

    We present a 3-D model of P and S velocities beneath El Hierro Island, constructed using the traveltime data of more than 13 000 local earthquakes recorded by the Instituto Geográfico Nacional (IGN, Spain) in the period from 2011 July to 2012 September. The velocity models were performed using the LOTOS code for iterative passive source tomography. The results of inversion were thoroughly verified using different resolution and robustness tests. The results reveal that the majority of the onshore area of El Hierro is associated with a high-velocity anomaly observed down to 10-12-km depth. This anomaly is interpreted as the accumulation of solid igneous rocks erupted during the last 1 Myr and intrusive magmatic bodies. Below this high-velocity pattern, we observe a low-velocity anomaly, interpreted as a batch of magma coming from the mantle located beneath El Hierro. The boundary between the low- and high-velocity anomalies is marked by a prominent seismicity cluster, thought to represent anomalous stresses due to the interaction of the batch of magma with crust material. The areas of recent eruptions, Orchilla and La Restinga, are associated with low-velocity anomalies surrounding the main high-velocity block. These eruptions took place around the island where the crust is much weaker than the onshore area and where the melted material cannot penetrate. These results put constraints on the geological model that could explain the origin of the volcanism in oceanic islands, such as in the Canaries, which is not yet clearly understood.

  11. Proof-of-principle results for identifying the composition of dust particles and volcanic ash samples through the technique of photon activation analysis at the IAC

    Science.gov (United States)

    Mamtimin, Mayir; Cole, Philip L.; Segebade, Christian

    2013-04-01

    Instrumental analytical methods are preferable in studying sub-milligram quantities of airborne particulates collected in dust filters. The multi-step analytical procedure used in treating samples through chemical separation can be quite complicated. Further, due to the minute masses of the airborne particulates collected on filters, such chemical treatment can easily lead to significant levels of contamination. Radio-analytical techniques, and in particular, activation analysis methods offer a far cleaner alternative. Activation methods require minimal sample preparation and provide sufficient sensitivity for detecting the vast majority of the elements throughout the periodic table. In this paper, we will give a general overview of the technique of photon activation analysis. We will show that by activating dust particles with 10- to 30-MeV bremsstrahlung photons, we can ascertain their elemental composition. The samples are embedded in dust-collection filters and are irradiated "as is" by these photons. The radioactivity of the photonuclear reaction products is measured with appropriate spectrometers and the respective analytes are quantified using multi-component calibration materials. We shall provide specific examples of identifying the elemental components of airborne dust particles and volcanic ash by making use of bremsstrahlung photons from an electron linear accelerator at the Idaho Accelerator Center in Pocatello, Idaho.

  12. Active Learning Framework for Non-Intrusive Load Monitoring: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xin

    2016-05-16

    Non-Intrusive Load Monitoring (NILM) is a set of techniques that estimate the electricity usage of individual appliances from power measurements taken at a limited number of locations in a building. One of the key challenges in NILM is having too much data without class labels yet being unable to label the data manually for cost or time constraints. This paper presents an active learning framework that helps existing NILM techniques to overcome this challenge. Active learning is an advanced machine learning method that interactively queries a user for the class label information. Unlike most existing NILM systems that heuristically request user inputs, the proposed method only needs minimally sufficient information from a user to build a compact and yet highly representative load signature library. Initial results indicate the proposed method can reduce the user inputs by up to 90% while still achieving similar disaggregation performance compared to a heuristic method. Thus, the proposed method can substantially reduce the burden on the user, improve the performance of a NILM system with limited user inputs, and overcome the key market barriers to the wide adoption of NILM technologies.

  13. Targeted Proteomics Approaches To Monitor Microbial Activity In Basalt Aquifer

    Science.gov (United States)

    Paszczynski, A. J.; Paidisetti, R.

    2007-12-01

    Microorganisms play a major role in biogeochemical cycles of the Earth. Information regarding microbial community composition can be very useful for environmental monitoring since the short generation times of microorganisms allows them to respond rapidly to changing environmental conditions. Microbial mediated attenuation of toxic chemicals offers great potential for the restoration of contaminated environments in an ecologically acceptable manner. Current knowledge regarding the structure and functional activities of microbial communities is limited, but more information is being acquired every day through many genomic- and proteomic- based methods. As of today, only a small fraction of the Earth's microorganisms has been cultured, and so most of the information regarding the biodegradation and therapeutic potentials of these uncultured microorganisms remains unknown. Sequence analysis of DNA and/or RNA has been used for identifying specific microorganisms, to study the community composition, and to monitor gene expression providing limited information about metabolic state of given microbial system. Proteomic studies can reveal information regarding the real-time metabolic state of the microbial communities thereby aiding in understanding their interaction with the environment. In research described here the involvement of microbial communities in the degradation of anthropogenic contaminants such as trichloroethylene (TCE) was studied using mass spectrometry-based proteomics. The co- metabolic degradation of TCE in the groundwater of the Snake River Plain Aquifer at the Test Area North (TAN) site of Idaho National Laboratory (INL) was monitored by the characterization of peptide sequences of enzymes such as methane monooxygenases (MMOs). MMOs, expressed by methanotrophic bacteria are involved in the oxidation of methane and non-specific co-metabolic oxidation of TCE. We developed a time- course cell lysis method to release proteins from complex microbial

  14. Cadence Feedback With ECE PEDO to Monitor Physical Activity Intensity

    Science.gov (United States)

    Ardic, Fusun; Göcer, Esra

    2016-01-01

    Abstract The purpose of this study was to examine the monitoring capabilities of the equipment for clever exercise pedometer (ECE PEDO) that provides audible feedback when the person exceeds the upper and lower limits of the target step numbers per minute and to compare step counts with Yamax SW-200 (YX200) as the criterion pedometer. A total of 30 adult volunteers (15 males and 15 females) were classified as normal weight (n = 10), overweight (n = 10), and obese (n = 10). After the submaximal exercise test on a treadmill, the moderate intensity for walking was determined by using YX200 pedometer and then the number of steps taken in a minute was measured. Lower and upper limits of steps per minute (cadence) were recorded in ECE PEDO providing audible feedback when the person's walking speed gets out of the limits. Volunteers walked for 30 minutes in the individual step count range by attaching the ECE PEDO and YX200 pedometer on both sides of the waist belt in the same session. Step counts of the volunteers were recorded. Wilcoxon, Spearman correlation, and Bland–Altman analyses were performed to show the relationship and agreement between the results of 2 devices. Subjects took an average of 3511 ± 426 and 3493 ± 399 steps during 30 minutes with ECE PEDO and criterion pedometer, respectively. About 3500 steps taken by ECE PEDO reflected that this pedometer has capability of identifying steps per minute to meet moderate intensity of physical activity. There was a strong correlation between step counts of both devices (P PEDO and YX200 pedometer in the Bland–Altman analysis. Although both devices showed a strong similarity in counting steps, the ECE PEDO provides monitoring of intensity such that a person can walk in a specified time with a desired speed. PMID:26962822

  15. Explosive and Phreatomagmatic Activity from San Salvador Volcanic Complex (El Salvador) and Their Effects on El Cambio Archaeological Site: a Review of the Last 3000 yrs. Based on Volcanic Stratigraphy Data

    Science.gov (United States)

    Ferrés, D.; Delgado, H.; Pullinger, C.; Castillo, R.; Chávez, H. I.

    2007-05-01

    El Cambio archeological site (ECAS; Zapotitán Valley), 4 km NW from the San Salvador Volcanic Complex comprises 3000 yrs. of pyroclastic record. Sheets (1983) identified different levels rich in cultural remains intercalated within the volcanic deposits, indicating that different prehistoric settings were affected by San Salvador volcano eruptions, and giving information on the reoccupation frequency in the area. Accordingly, ECAS was occupied since the Late Pre-Classic period until before the last plinian eruption of Ilopango Caldera (425AD) reference, that originated the Tierra Blanca Joven (TBJ), pyroclastic deposits generally used as key-layer in stratigraphic reconstructions. Within the next two centuries, there is no evidence of human occupation at ECAS until the end of Late Classic which was a period of maximum splendor in the valley. During this time the area was affected by at least 3 eruptions from the San Salvador volcanic complex that produced the: Laguna Caldera volcanic fall deposits (which affected Joya de Cerén archeological site in 625AD), "Talpetate" surge deposits or Toba de San Andrés (600-900AD), and fall deposits of El Playón volcano (1658). We report new data on volcanic stratigraphy and archeological history including the following: a) the phreatomagmatic nature of eruptions that affected the area, the new excavations allowed the detailed study of surge deposits indicating magma-water interaction at Laguna Caldera and El Playón, previously considered strombolian eruptions; b)document the occupation of ECAS during Middle Pre-Classic period, new surge deposits below TBJ have been identified (with Middle Pre-Classic artifacts and pottery), that had not been documented before, extending the historic record up to 3000 yrs. BP. and c) detailed study of the "Talpetate" deposits, this sequence consists of fall, pyroclastic flow and surge deposits, present in the rim and slopes of San Salvador Volcano, which can be correlated with surge deposits

  16. Monitoring daily function in persons with transfemoral amputations using a commercial activity monitor: a feasibility study.

    Science.gov (United States)

    Albert, Mark V; Deeny, Sean; McCarthy, Cliodhna; Valentin, Juliana; Jayaraman, Arun

    2014-12-01

    To assess in a feasibility study the mobility of persons with transfemoral amputations using data collected from a popular, consumer-oriented activity monitor (Fitbit). Observational cohort study. Research hospital outpatient evaluation. Nine subjects with transfemoral amputations (4 women and 5 men, ages 21-64 years) and Medicare functional assessments (K level) of K3 (n = 7), K2 (n = 1), and K4 (n = 1). One-week monitoring of physical activity using the Fitbit One activity monitor. Daily estimates of step counts, distance walked, floors/stairs climbed, calories burned, and proprietary Fitbit activity scores. For each day, the amount of time in each of the following levels of activity was also reported: sedentary, lightly active, fairly active, and highly active. The percentage of movement time above the fairly active level had a predictable relationship to the designated K level. The average activity measures show decreased levels of activity for obese subjects (body mass index >30). Estimated step counts were highly predictive/redundant with estimated miles walked without setting individual stride lengths. Using linear regression prediction models, calorie estimates were found to be highly dependent on subject age, height, and weight, whereas the proprietary activity score was independent of all 3 demographic factors. This feasibility study demonstrates that the Fitbit activity monitor estimates the activity of subjects with transfemoral amputations, producing results that correlate with their K-level functional activity classifications. The Fitbit activity score is independent of individual variations in age, weight, and height compared with estimated calories for this small sample size. These tools may provide useful insights into prosthetic use in an at-home environment. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  17. Volcanic gas impacts on vegetation at Turrialba Volcano, Costa Rica

    Science.gov (United States)

    Teasdale, R.; Jenkins, M.; Pushnik, J.; Houpis, J. L.; Brown, D. L.

    2010-12-01

    Turrialba volcano is an active composite stratovolcano that is located approximately 40 km east of San Jose, Costa Rica. Seismic activity and degassing have increased since 2005, and gas compositions reflect further increased activity since 2007 peaking in January 2010 with a phreatic eruption. Gas fumes dispersed by trade winds toward the west, northwest, and southwest flanks of Turrialba volcano have caused significant vegetation kill zones, in areas important to local agriculture, including dairy pastures and potato fields, wildlife and human populations. In addition to extensive vegetative degradation is the potential for soil and water contamination and soil erosion. Summit fumarole temperatures have been measured over 200 degrees C and gas emissions are dominated by SO2; gas and vapor plumes reach up to 2 km (fumaroles and gases are measured regularly by OVSICORI-UNA). A recent network of passive air sampling, monitoring of water temperatures of hydrothermal systems, and soil pH measurements coupled with measurement of the physiological status of surrounding plants using gas exchange and fluorescence measurements to: (1) identify physiological correlations between leaf-level gas exchange and chlorophyll fluorescence measurements of plants under long term stress induced by the volcanic gas emissions, and (2) use measurements in tandem with remotely sensed reflectance-derived fluorescence ratio indices to track natural photo inhibition caused by volcanic gas emissions, for use in monitoring plant stress and photosynthetic function. Results may prove helpful in developing potential land management strategies to maintain the biological health of the area.

  18. The Lada Terra rise and Quetzalpetlatl Corona: A region of long-lived mantle upwelling and recent volcanic